• The Transactions of the Korean Institute of Electrical Engineers C
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• v.53 no.12
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• pp.616-619
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• 2004

Electrical circuits with semiconductor are very weak against lightning surge. The surge protective devices for electronic circuit and AC power lines are becoming more widely used. To achieve effective method of surge protection, there are needs for correlation between lightning surge and indoor wire length or installation height of indoor wire. The aim of this present work is to investigate the propagation characteristics of lightning surge according to variation of wire length. As a consequence, the maximum voltage at the end of the open wire in proportion to length of indoor wire. Therefore this result may be raw data for establishment of surge protection system.

• Journal of Korea Multimedia Society
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• v.9 no.10
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• pp.1371-1379
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• 2006

This paper suggests the padding algorithm using padding character length to concatenate more than one string without side-effect. Most existing padding algorithms padding null character in the empty location could not discriminate the real string from the padded character. To overcome this problem, in this paper, the padded character contains pad character length information. This mechanism is working better than NULL or '00' padding cases. The suggested padding algorithm could be effective for data encryption and decryption algorithms.

• Nuclear Engineering and Technology
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• v.44 no.6
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• pp.639-652
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• 2012

A three-dimensional discrete fracture network model was developed in order to simulate the hydraulic characteristics of a granitic rock mass at Korea Atomic Energy Research Institute (KAERI) Underground Research Tunnel (KURT). The model used a three-dimensional discrete fracture network (DFN), assuming a correlation between the length and aperture of the fractures, and a trapezoid flow path in the fractures. These assumptions that previous studies have not considered could make the developed model more practical and reasonable. The geologic and hydraulic data of the fractures were obtained in the rock mass at the KURT. Then, these data were applied to the developed fracture discrete network model. The model was applied in estimating the representative elementary volume (REV), the equivalent hydraulic conductivity tensors, and the amount of groundwater inflow into the tunnel. The developed discrete fracture network model can determine the REV size for the rock mass with respect to the hydraulic behavior and estimate the groundwater flow into the tunnel at the KURT. Therefore, the assumptions that the fracture length is correlated to the fracture aperture and the flow in a fracture occurs in a trapezoid shape appear to be effective in the DFN analysis used to estimate the hydraulic behavior of the fractured rock mass.

• Journal of Korea Game Society
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• v.14 no.6
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• pp.29-38
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• 2014

In the large scale indoor 3D game scenes, the data amount of potentially visible set (PVS) which pre-computes the information of occlusion culling can be huge. However, the large part of them can be represented as zero. In this paper, the effective hardware structure is designed, which compresses PVS data as the way of zero run length encoding (ZRLE) during building the scene trees of 3D games in mobile environments. The compression ratio of the proposed structure and the rendering speed (frame per second: FPS) according to both PVS culling and frustum culling are analyzed under 3D game simulations.

• Transactions of the Korean Society of Mechanical Engineers
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• v.18 no.2
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• pp.351-358
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• 1994

A probabilistic model and analysis methods to determine the means and variances of the velocity and acceleration in stochastically-defined planar pin jointed kinematic chains are presented. The presented model considers the effect of tolerances on link length and radial clearance and uncertainty of pin location as a net effect on the link's effective length. The determination of the mean values and variances of the output variables requires the calculation of sensitivities of secondary variables with respect to the random variables. It is shown that this computation is straightforward and can be accomplished by a conventional kinematic analysis package with minor modification. Thus, the concepts of tolerance and clearance have been captured by the model and analysis. The only input data are the nominal linkage model and statistical information. The "effective link length" model is shown to be applicable to both analytical solution and Monte Carlo simulation. The results from both methods are compared. This paper Ksolves the higher-order kinematic problems for the probabilistic design analysis of stochastically-defined mechanisms.echanisms.

• Journal of the Korean Solar Energy Society
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• v.28 no.2
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• pp.50-57
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• 2008

This study intends to evaluate the effect on indoor environment(annual thermal load, sunshine)by the application of the movable horizontal shading device on summer and winter season. For these purpose, we supposed the models which are composed of the several horizontal shading devices. Then we analyzed the simulation using the IES5.5.1 and Seoul weather data. The results of this study are as follows: 1) The proper length, angle of horizontal shading device is 2.1m, 28 degree, respectively. 2) The decreasing rate of the annual load of the Movable Horizontal Shading Model(MHSM) in comparison with the No Shading Model(NSM) & Conventional Horizontal Shading Model(CHSM) is 31.11%, 6.63% respectively. 3) The decrease of sunshine of the MHSM on summer season is effective the alleviation of visual displeasure. On the other hand, the increase of sunshine of the MHSM on winter season is effective the psychological comfort. Further study is to be required the sensitivity analysis on the various shading length for the realistic proper shading length.

• PNF and Movement
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• v.7 no.1
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• pp.1-8
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• 2009

Purpose : The aim of this study was to determine the effect of Proprioceptive Neuromuscular Facilitation (PNF) on gait ability in hemiplegic patients. Method : The subjects of this study were 11 hemiplegic patients. Each subject was taken PNF exercise with 3 times per week for 4 weeks. Pre- and post-intervention change in gait ability were measured using an 6m walking test, stride length, and step length. The data were analyzed using the paired t-test. Results : The results of this study showed significantly improvement in 6m walking test, stride length, and step length after intervention. Conclusion : These results suggest that the PNF coordination exercise is an effective way of improving gait ability for hemiplegic patients.

• PNF and Movement
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• v.9 no.2
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• pp.1-7
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• 2011

Purpose : The purpose of this research was to determine the effects of Proprioceptive Neuromuscular Facilitation(PNF) and Functional Electrical Stimulation(FES) of combined on gait ability in hemiplegic gait. Methods : The subjects of this study were 13 hemiplegic patients. Each subjects was taken PNF pattern and FES of combined with 5 times per week for 4weeks. Pre- and Post-intervention change in gait ability were measured using an Timed up and Go test, stride length of the affected side, step length of the affected side. The data were analyzed using the paired t-test. Results : The results of this study were showed significantly improvement in TUG, stride length of the affected side, step length of the affected side after intervention. Conclusion : These results suggest that the Proprioceptive Neuromuscular Facilitation(PNF) and Functional Electrical Stimulation(FES) of combined exercise is an effective way of improving gait ability for hemiplegic patients.

• Korean Journal of Hospice Care
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• v.3 no.2
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• pp.55-60
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• 2003

Purpose: The appropriate duration for effective hospice care is estimated about 3 months. However, the length of hospice care of many hospice patients is mostly less than 1 months. This is too short for effective hospice care. Therefore we investigated the reason by clinical considuations include the length of hospie care, duration from diagnosed as terminatlly ill to refer to hospice, the recogntion of hospice of doctors, patients and familis. Methods: This study was designed to retrospective cohot study. The data was obtaind from 50 hospice patients those who died in hospital from July to September in 2003. Results: Out of 50 patient, 30 were male(60%). The median age wes 60years in males and was 61 years in femailes. The most prevalant cancer was colorectal cancer(9 patients, 18%), followed by hepatoma(8 patients, 16%), and stomach cancer(7 patients, 14%). The most prevalent symptom was pain(37 patients 74%) and most prevalant reason of admission was also pain(30 patients, 60%). The most prevalent physician specialty was general internal medicine(21 doctors, 42%), followed by oncology(19 doctors, 38%). The median days form diagnosed terminally ill to refere to hospice was 47 days. The median lengths of hospice care was 23 days and the median admission days was 17. Conclusion: We found that lack of recognition of hospice of doctors, patients and families made the lengths of hospice care too short. If the patient and family go to hospice just after diagnosed as terminally ill, they could get more effective hospice care. To resolve these problems, it is needed education for them constantly.

• Journal of Korean Society on Water Environment
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• v.30 no.2
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• pp.159-165
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• 2014

Vegetative Filter Strip (VFS) is one of effective Best Management Practices (BMPs) to prevent sediment-laden water problem, is installed at the edge of source area such agricultural area so that sediment occurred in source area is trapped by VFS before it flow into stream or river. Appropriate scale of it needs to be simulated before it is installed, considering various field conditions. In this study, a model using VFSMOD-w model and Genetic Algorithm to determine effective VFS length was developed, it is available to calibrate input parameter related to source area sediment yield through thousands of VFSMOD-w simulations. Useful DBs, moreover, are stored in the model so that very specific input parameters can be used with reasonable values. Compared simulated values to observed data values for calibration, R2 and Nash-Stucliffe model efficiency coefficient were 0.74 and 0.65 in flow comparison, and 0.89 and 0.79 in sediment comparison. The model determined 1.0 m of Filter Length, 0.18 of Filter Slope, and 0.2 cm of Filter Media Spacing to reduce 80% of sediment by VFS. The model has not only Auto-Calibration module also DBs for specific input parameters, thus, the model is expected to be used for effective VFS scale.