• Proceedings of the KIEE Conference
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• 2006.11a
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• pp.243-245
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• 2006

In this paper, the master system of Wide Area Monitoring System in order to prevent reaching a fault influence toward power system is proposed. This system has three real time algorithms and a on-line one using i-piu transfer data and provides operators with various understandable monitoring viewers in HMI based on raw data and algorithm results.

• Proceedings of the KSME Conference
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• 2001.11b
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• pp.585-590
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• 2001

The hemodynamic characteristics were compared using commercial CFD code for the stenosed coronary and abdominal arteries. Numerical calculations were carried out in the axisymmetric arteries over the stenotic diameter ratios ranging from 0.25 to 0.875 (6 cases) employing the typical physiological flow conditions. In case of the coronary artery, there was only one recirculation zone observed distal to the stenosis throat during the major portion of the period. However, in case of the abdominal aorta, there were complex recirculation regions found proximal and distal to stenosis throat. For both models, the wall shear stresses(WSS) increased sharply in the converging stenosis, reaching a peak just upstream of the throat, and became negative or low values in the post-stenotic recirculation region. As the results, the oscillatory shear index(OSI) was abruptly increased at the stenosis throat. For the coronary stenosis model, the second peak in the OSI was observed distal to the stenosis. The distance between the first peak and the second peak was increased as the degree of the stenosis was raised. On the orther hand, the abdominal stenosis model showed a complex oscillatory behavior in the OSI index and did not showed such a strong second peak. As the degree of stenosis was increased, recirculation regions of the both arteries were extended much longer and flow pattern became more complex.

• Journal of ILASS-Korea
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• v.22 no.3
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• pp.109-115
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• 2017

The aim of this study is to investigate the effect of physical properties of fuels on spray characteristics in the gasoline direct injection system. Injection rate, spray visualization, and spray pattern experiments were performed to analyze the spray characteristics of ethanol, gasoline, and ethanol/gasoline blends. We measured injection rate of each fuel via the Bosch method. The spray visualization experiment was also carried out at atmospheric pressure using a high-speed camera. Finally, the average of drop surface area per unit volume was measured using the optical patternator. The experimental results from Bosch method showed that peak injection rate increased when the volume fraction of ethanol increased. In addition, higher viscosity of ethanol than that of gasoline leads to longer injection delay. At the initial injection region before reaching 0.8 ms, the spray tip penetration becomes longer as increasing the volume fraction of ethanol, but reversely shorter after 0.8 ms. It was found that ethanol makes spray angle become larger. The surface area per unit volume of the drop was decreased as the distance from the injection tip or the concentration of the gasoline increased.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.14 no.3
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• pp.51-56
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• 2014

TETRA(TErrestrial Trunked RAdio) provide specialized disaster radio communication services as a standard European for digital TRS(Trunked Radio System). Especially, DMO(Direct Mode Operation) feature is used effectively in the radio shadow areas which base station does not propagate radio signal because it can communicate directly with terminal to terminal without base station's relay function. However, to effectively used DMO feature, radio coverage prediction information should be provided to users. Therefore in this paper, we were calculated link budget of TETRA DMO terminals which were distributing and operating in the country and then predicted reaching distance about radio propagation to be applied with path loss model.

• PNF and Movement
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• v.5 no.2
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• pp.55-62
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• 2007

Purpose : The purpose of this study was to examine the effects of Rhythmic Stabilization(RS) and Combination of Isotonic(CI) of Proprioceptive Neuromuscular Facilitation on balance in patients with hemiplegia. Methods : Ten patients with hemiplegia were trained with RS and CI for six weeks. Two Standard Scale(TSS), Functional Reach Test(FRT), Time Up and Go test(TUG) and Berg Balance Scale(BBS) were used to prove their improvement of balance. Results : Body weight bearing decreased on less affected side and increased on more affected side. Distance of forward reaching for FRT increased. Time for TUG decreased. BBS score increased. They all showed significant difference. Conclusion : This study suggests that balance training with RS and CI of Proprioceptive Neuromuscular Facilitation improved balance in patients with hemiplegia.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2006.05a
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• pp.301-304
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• 2006

As is different from formerly used fixing camera method in this paper, proposed method that can measure the speed of vehicles and logarithm of vehicles in video. Vehicles that proposed method runs with 50km/h, 80km/h, 90km/h's the speed recording on Video Tape beginning point and time of reaching point draw, and calculated 47.57km/h, 81.20km/h, the 90.00km/h speed by time and distance, the tracking cars and the velocity detection in video with the 'begin-line mark' and the 'end-line mark' processing.

• Journal of Biosystems Engineering
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• v.7 no.2
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• pp.30-35
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• 1983

To investigate the factors affecting the transportability of spray droplets, the maximum distance, the effective distance, the ratio of even distribution, and the diameters of particles were measured in accordance with the different pressure levels of power sprayer using 3 hole swath type nozzle, and the results are summerized as follows; 1. The distance of the most dense point from the nozzle was shortened by 0.5 meter with the 100-meter-long hose. The maximum reaching distances were reduced by 1.5 and 1.0 meters for the 13m/m and the 8.5 m/m hoses respectively, and the effective distance were reduced by 0.5 meter for both cases. 2. The effective distance can not be extended beyond 14 meters even if the length of hose is minimized at the rated pump pressure 28 kg/$cm^2$, it was 1 meter longer for 13m/m hose compared to the 8.5m/m one. 3. In case of 13m/m hose, the most dense point can be extended further by 0.5 meter increasing the pump pressure by 8 kg/$cm^2$, and the maximum distance and effective distance were increased by 2.0 and 0.5 meters respectively. There was no significant effect of pressure changes on the transportability in case of 8.5m/m hose. 4. Both the reduction of hose length and the increase of pump pressure influenced in large extent to the atomization effect of droplets. It was noticed that the diameter of droplet is related to the pump pressure and inside diameter of hose. 5. The pressure drop in 100-meter-long and l3m/m hose was 5~7kg/$cm^2$ at the pump pressure range of 25~33kg/$cm^2$, and it is an equivalent of 2% per 10 meter length of hose.

• Korean Journal of Soil Science and Fertilizer
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• v.18 no.4
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• pp.336-347
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• 1985

Soils and rice plants subject to smoke from the Jang-hang Smelter were samples at two depths to assess the nature and extend of Cd, Cu, Pb, and Zn contamination, particularly with respect to distance from pollution source. Soils at east site within 1km of the center of the smelter were highly contaminated with Cd, Cu, Pb, and Zn. Metal levels in the smoke-polluted area were higher in surface soil than in subsurface soil, and decreased rapidly with distance reaching nearly background levels at 5km from pollution source. A position correlation was found between contents of total and 0.1 N HCl-extractable, or 1.0N $CH_3COONH_4$- extractable heavy metals in surface soils of pollution. Contents of heavy metals in soils were positively correlated with soil organic matter and cation exchange capacity. The contents of heavy metals in brown rice collected from the paddy field around the Jang-hang Smelter were in the range of 0.23-1.33 ppm for Cd, 2.39-6.25 for Cu, 0.95-8.32 ppm for Pb and 14.60-27.31 for Zn. The contents of Cd, Cu, and Zn in rice straw were positively correlated with those in the brown rice. Negative correlation was found between the contents of Cd, Cu, Pb, and Zn in brown rice and the distance from the source.

• Korean Journal of Radiology
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• v.22 no.5
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• pp.829-839
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• 2021

Objective: To compare the diagnostic performance of contrast-enhanced radial T1-weighted gradient-echo 3-tesla (3T) magnetic resonance imaging (MRI) and computed tomography (CT) for the detection of visceral pleural surface invasion (VPSI). Visceral pleural invasion by non-small-cell lung cancer (NSCLC) can be classified into two types: PL1 (without VPSI), invasion of the elastic layer of the visceral pleura without reaching the visceral pleural surface, and PL2 (with VPSI), full invasion of the visceral pleura. Materials and Methods: Thirty-three patients with pathologically confirmed VPSI by NSCLC were retrospectively reviewed. Multidetector CT and contrast-enhanced 3T MRI with a free-breathing radial three-dimensional fat-suppressed volumetric interpolated breath-hold examination (VIBE) pulse sequence were compared in terms of the length of contact, angle of mass margin, and arch distance-to-maximum tumor diameter ratio. Supplemental evaluation of the tumor-pleura interface (smooth versus irregular) could only be performed with MRI (not discernible on CT). Results: At the tumor-pleura interface, radial VIBE MRI revealed a smooth margin in 20 of 21 patients without VPSI and an irregular margin in 10 of 12 patients with VPSI, yielding an accuracy, sensitivity, specificity, positive predictive value, negative predictive value, and F-score for VPSI detection of 91%, 83%, 95%, 91%, 91%, and 87%, respectively. The McNemar test and receiver operating characteristics curve analysis revealed no significant differences between the diagnostic accuracies of CT and MRI for evaluating the contact length, angle of mass margin, or arch distance-to-maximum tumor diameter ratio as predictors of VPSI. Conclusion: The diagnostic performance of contrast-enhanced radial T1-weighted gradient-echo 3T MRI and CT were equal in terms of the contact length, angle of mass margin, and arch distance-to-maximum tumor diameter ratio. The advantage of MRI is its clear depiction of the tumor-pleura interface margin, facilitating VPSI detection.

• Fire Science and Engineering
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• v.33 no.6
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• pp.9-19
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• 2019

In fire simulations for building fire safety evaluation, changes in the fire area and grid size can significantly influence the prediction results. Therefore, the effects of area changes of the fire source with identical maximum heat release rates on the prediction results of a compartment fire were investigated. The dependence of the prediction results on the grid size using the identical fire area was also examined. No significant changes were observed in the thermal and chemical characteristics of the fires with variable grid sizes, even though the fire area was changed when six or more grids were set based on the fire diameter. In addition, changes in the fire area caused significant differences in the prediction of major physical quantities associated with available safety egress time (ASET) within a compartment. However, the fire area changes did not considerably influence the overall fire characteristics outside the compartment after reaching a certain distance from the opening.