• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2007.11a
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• pp.89-92
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• 2007

In the present study, the flow field in a square container with various comer rounding is studied to investigate drain flow characteristics. An attempt has been made to understand the mechanism that is responsible for vortex suppressing by the different radius of rounding at the comer. For this purpose, flow visualization studies using PIV (Particle Image Velocimetry) are employed to determine the flow patterns in a square tank. Results are obtained when there is no draining and with draining. The flow field is visualized both in horizontal and vertical planes.

• Journal of applied mathematics & informatics
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• v.7 no.3
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• pp.765-772
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• 2000

In this study we are concerned with the problem of approximating a solution of a nonlinear equation in Banach space using Newton-like methods. Due to rounding errors the sequence of iterates generated on a computer differs from the sequence produced in theory. Using Lipschitz-type hypotheses on the second Frechet-derivative instead of the first one, we provide sufficient convergence conditions for the inexact Newton-like method that is actually generated on the computer. Moreover, we show that the ratio of convergence improves under our conditions. Furthermore, we provide a wider choice of initial guesses than before. Finally, a numerical example is provided to show that our results compare favorably with earlier ones.

• Journal of computational fluids engineering
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• v.19 no.1
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• pp.57-63
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• 2014

This study performed numerical analysis for the characteristics of flow-induced forces and the flow instability depending on the cross-sectional shape of the cylinder in laminar flow. To implement the cylinder cross-section, we adopted an Immersed Boundary Method with marker particles. We analyzed flow characteristics based on the radius of corner curvature. Main parameters are corner radius and Reynolds number (Re). With Re = 40, 50, 150 we calculated the flow field, drag coefficient, RMS of lift coefficient, pressure coefficient and Strouhal number in conjunction with the corner radius variation. Also, we calculated critical Reynolds number ($Re_c$) depending on the corner radius variation.

• Journal of Korean Medical classics
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• v.17 no.4
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• pp.37-56
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• 2004

In the Circular flow of Meridians(經脈), the circulation of Nutrient Gi(營氣) is that the essence Gi(精氣) of food starts from Middle Cho(中焦), via heart and lung into the ring-type round of 12 Meridians(十二經脈) in turn of hand Meridians(水經) and foot Meridians(足經), Yang Meridians(陽經) and Eum Meridians(陰經). The circulation of Defensive Gi(衛氣) is that if going out from Eum part(陰分) into Yang part(陽分), is rounding on the Yang Meridians, if going out from Yang part into Eum part, is rounding on the five Jang(五臟) in order of Kidney(腎)-Heart(心)-Lung(肺)-Liver(肝)-Spleen(脾). Because the process of accumulating the essence Gi has a property of One-way flow, it flows from terminal to the direction of body trunk, has no distinct channel with its immaterial nature. and is concentrated on the lower part to that the five Jang belong.

• International Journal of Precision Engineering and Manufacturing
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• v.4 no.4
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• pp.25-31
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• 2003

A computer simulation model for investigating a two-dimensional (2-D) rounding mechanism in a centerless grinding process is described. This model includes the interference phenomena and the concept of machining elasticity. Since initial contact points are used as a reference, the result of this simulation is not affected by the location of the reference circle center and the radius of the reference circle. Also, details of the machining factor are studied by using process variables (grinding wheel speed, wheel specification, workpiece speed, dressing condition, etc.). The effect of the threshold grinding force on the size of ground workpiece is investigated. For the verification of this method, simulation results are compared with the experimental work.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2007.04a
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• pp.313-316
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• 2007

In the present study, the flow field in a square container with various corner rounding is studied to investigate drain flow characteristics. An attempt has been made to understand the mechanism that is responsible for vortex suppressing by the different radius of rounding at the corner. For this purpose, flow visualization studies using PIV (Particle Image Velocimetry) are employed to determine the flow patterns in a square tank. Results are obtained when there is no draining and with draining. The flow field is visualized both in horizontal and vertical planes.

• Journal of the Optical Society of Korea
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• v.16 no.3
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• pp.221-227
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• 2012

We propose optical proximity corrections (OPCs) for digital micromirror device (DMD)-based maskless lithography. A pattern writing scheme is analyzed and a theoretical model for obtaining the dose distribution profile and resulting structure is derived. By using simulation based on this model we were able to reduce the edge placement error (EPE) between the design width and the critical dimension (CD) of a fabricated photoresist, which enables improvement of the CD. Moreover, by experiments carried out with the parameter derived from the writing scheme, we minimized the corner-rounding effect by controlling light transmission to the corners of a feature by modulating a DMD.

• Korean Journal of Community Nutrition
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• v.5 no.1
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• pp.83-91
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• 2000

The aims of this study are to evaluate the quality of hospital food services and the evaluate the quality in selected hospitals trough the use of the questionnaires. A survey of 30 hospital food and nutrition service department was undertaken and detailed information was collected from each, including, surveys of 1, 016 patient. Statistical data analysis was completed using the SAS/win 6.11 package for descriptive analysis, t-test X$^2$-test ANOVA principal component analysis , and cluster analysis and cluster analysis. In the case of patient satisfaction with hospital food and food services, overall satisfaction scores of male and female were 3.54 and 3.45 showing higher levels than the average score(3.00) The aspect of the food and food service which received the lowest ratings by patients was 'meal rounding while dining'. After conduction of factor analysis of variables affecting the patients meal satisfaction 3 groups including the 'menu satisfaction factor', 'service satisfaction factor ' and 'nutrition management satisfaction factor ' were selected. 3 clusters were categorized by the 'service cluster' 'nutrition management cluster', 'men cluster', and 'menu nutrition service cluster' after conducting a cluster analysis with influencing variables affecting patients meal satisfaction. The overview results of patient satisfaction by cluster were : in the case of the service group, such factors as taste, portion size, dealing with complaints while dining meal rounding while dining should be managed with caution In case of the nutrition management group, such factors as taste, portion size, temperature of the food intake, and dependence on hospital food should be managed with care, In the case of the menu groups, such factors as punctuality of meal times, contaminated substances in meals and serving mistakes, cleanliness of dishes, kindness of the server meal rounding while dining should by particularly managed with importance.

• Journal of Broadcast Engineering
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• v.15 no.6
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• pp.853-867
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• 2010

Recently, thumbnail techniques are required to index a high-performance video at digital convergence-based multimedia service like IPTV and DMB. Therefore a thumbnail extraction method in H.264/AVC bitstreams has been proposed. However, thumbnail quality deterioration problem at converting the general equation of spatial domain to frequency domain which is generated by not considering about H.264/AVC transform and quantization processing and rounding-off operation in intra prediction. In this paper, we propose a new thumbnail extraction method in H.264/AVC bitstreams. The proposed scheme is based on H.264/AVC core-transform for a thumbnail extraction in frequency domain, and probability theory, intra rounding-off error compensation. Through the implementation and performance evaluation, the subjective quality difference between the output of our scheme and the output of reference decoder is negligible and better than the conventional method, and moreover PSNR gain by up to 8.66 dB.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.29 no.11A
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• pp.1271-1277
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• 2004

We propose a foe phase tuner and a rounding processor for a numerically controlled oscillator (NCO), yielding a reduced phase error in generating a digital sine waveform. By using the fine Phase tuner Presented in this paper, when the ratio of the desired sine wave frequency to the clock frequency is expressed as a fraction, an accurate adjustment in representing the fractional value can be achieved with simple hardware. In addition, the proposed rounding processor reduces the effects of phase truncation on the output spectrum. Logic simulation results of the NCO for multi-carrier channel separation in cdma2000 3X multi-carrier receive system using these techniques show that the noise spectrum and mean square error (MSE) are reduced by 8.68 dB and 5.5 dB, respectively compared to those of truncation method and 2.38 dB and 0.83 dB, respectively, compared to those of Paul's scheme.