• Journal of the Korea institute for structural maintenance and inspection
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• v.27 no.3
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• pp.12-20
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• 2023

This study presents basic data on how to secure stability by analyzing the change in tensile force of steel rod and the inclination characteristics of PSC BOX in the "Temporary fixation system using internal prestressing tendon", which is mainly applied to construction of superstructures by FCM. To date, it has been difficult to confirm the changes in tension force of the steel rod and the inclination of the PSC BOX because the steel rod was installed vertically inside the pier and the PSC BOX. Therefore, measurement of the change in length of the steel rod and the displacement of PSC BOX were performed using a micro-measured FBG sensor. Comparisons of the calculated tensile force and the residual tensile force of the steel rod revealed that the safety factor decreased in all bridges. The cause was mainly identified to be the loss of tensile force in fixation~1segment, and countermeasures are suggested. The analysis of the inclination characteristics showed that the inclination increased with the segment progresses even in bridges with sufficient safety factor, and the difference before and after the segment was confirmed. In addition, the increase in inclination was related to the loss of tension force in the steel rod, and the stress on the opposite sides of the inclination was further reduced. It is believed that upward tensile force is generated in the steel rod on the opposite side of the inclined side due to the unbalanced moment, causing the difference in stress of the steel rod between the two sides.

• Transactions of the Korean Society of Machine Tool Engineers
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• v.10 no.4
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• pp.55-64
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• 2001

In this study, hemisphere and cylindrical shapes were machined for different tool paths and machining conditions with ball endmill cutters. Tool deflection, cutting forces and shape accuracy were measured according to the inclination position of the sculptured surface. As the decreasing of inclination position angle, the tool deflection was increased due to the decreased cutting speed when the cutting edge is approaching toward the center. Tool deflection when upward cutting is obtained less than that of downward cutting and down-milling in upward cutting showed the least tool deflection for the sculptured surface. Roundness values were found in least roundness error when down-milling in upward cutting. It is obtained the very little difference between 90。and 45。 of inclination position angle. The best surface roughness value was obtained in upward up-milling and showed different tendency with tool deflection and cutting force. For down-milling, the cutting resistance of the side wall direction is larger than that of feed direction. Therefore, this phenomenon which is received over cutting resistance can be caused of chatter.

• Journal of the Korean Society of Safety
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• v.31 no.3
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• pp.130-135
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• 2016

It is very hard to analyze the train derailment safety quantitatively at the curved section because of the diversified affect parameters including the complex interaction between wheel and rail, the train conditions such as the shape of wheel, suspension system, the track conditions such as the radius of curve, cant, transition curve, and the operation conditions, etc. Two major factors related to the running safety of railway vehicle are classified as the railway vehicle and the track condition. In this study, when the railway vehicle passing through curves of actual track condition of subway line NO.3 in seoul ($Yeonsinnae{\leftrightarrow}Gupabal$), the effect that has influence on running safety depending on rail inclination. The analysis result of 1/40 rail inclination condition is more favorable on running safety than other rail inclination conditions because derailment coefficient and wheel unloading ratio are the lowest.

• PNF and Movement
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• v.22 no.1
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• pp.139-149
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• 2024

Purpose: This study aimed to investigate the effects of gradually increasing treadmill inclination on the electroencephalogram (EEG) of stroke patients during gait training. Methods: Three stroke patients who were diagnosed with stroke within six months and capable of walking on a treadmill were selected as subjects. EEG electrodes were attached at Fp1, Fp2, F3, F4, C3, C4, P3, and P4 positions of the cerebral hemispheres using the International 10-20 system. The intervention involved walking for 2 minutes each at 0 degrees, 15 degrees, and 30 degrees inclination on the treadmill while focusing on a target point located in front during the treadmill gait training. The EEG (Smartingmobi, Serbia) generated when the treadmill gradient gradually increased was measured. In addition, relative alpha and relative beta waves were visualized through the Brain mapping program in the TeleScan program to assess the changes in each brain region for the activity of the EEG. Results: The relative alpha wave value decreased as treadmill inclination increased, while the relative beta wave value increased. Conclusion: Gradually increasing the inclination during treadmill gait training appears to be a crucial parameter for increasing the brain activity levels of stroke patients.

• The korean journal of orthodontics
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• v.27 no.2
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• pp.231-243
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• 1997

This study was carried out in order to find out the changes of the pharyngeal airway, hyoid bone and head posture before and after tonsillectomy in functional class III malocclusion patients. For this study, 21 Angle's class I patients and 21 Angle's class III patients, totally 42 subjects were chosen. The results were as follows; 1. In comparison to Class I group, tongue was more anteriorly and hyoid bone was more inferiorly positioned in functional Class III group 2. In comparison to pre-tonsillectomy, tongue was more posteriorly positioned and larger nasopharynx depth was shown in post-tonsillectomy. In post tonsillectomy, the hyoid bone was displaced posteriorly and superiorly and counterclockwise rotation was shown. 3. The level of significance for the correlation shown was 5 percent (p<0.05) indicating that: The change of nasopharyx depth was correlated to the inclination of lower incisors. Vertical change of tongue posture was correlated to the hyoid axis change. Vertical change of hyoid bone was correlated to the horizontal change of hyoid bone, craruocervical inclination. The change of craniocervical inclination was correlated to the inclination of lower incisors. 4. After the tonsillectomy, counterclockwise rotation of hyoid axis was associated with decease of hya-NL and large nasopharyngeal airway. High posture of the tongue was associated with decrease of hya-NL. Posterior posture of the tongue was associated with increase of h-hl,and decrease of hya-ba-n.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.37 no.1
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• pp.21-29
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• 2011

Introduction: To compare the change in frontal ramal inclination (FRI) in laterognathism after orthognathic surgery. Materials and Methods: Twenty four patients (10 men, 14 women; mean age, $22.8{\pm}5.2$ years) with minimal facial canting (${\leq}$ 2 mm) and apparent menton deviation ($5.9{\pm}2.4\;mm$) who had been operated on to correct facial asymmetry and skeletal CIII malocclusion, were selected. On a preoperative posteroanterior (PA) cephalogram, the FRI of the deviated side and non deviated side, L1 deviation amounts and menton deviation amounts were measured. The FRI differences between both sides were compared, and the correlations between the measured deviated elements and the FRI differences were analyzed. On a postoperative PA cephalogram, the shifting amount of L1, shifting amount of L7 and FRI of both sides were measured, and the correlations between the shifting elements and the change in FRI were analyzed. Results: On the preoperative PA cephalogram, the FRI of the non deviated side was significantly greater than those of the deviated side. The differences in FRI, with a menton deviation amount showed a significant correlation. On the postoperative PA cephalogram, the FRI differences between the deviated and non deviated side were decreased significantly and mandibular transverse movement toward central position was noted. The mean shifting amounts of L7 were associated with the amount of change in the deviated side of FRI. Conclusion: Transverse shifting of the mandible through orthognathic surgery decreases the FRI difference, which showed laterognathism, and improves the facial contour.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2000.11a
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• pp.43-46
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• 2000

Optical triangulation displacement sensors(0TDSs) are widely used for their simple struchlre, high resolution, and long operating range. However, there are several factors that must be taken into account in order to obtain high accuracy and reliability Measurement errors from inclinations a？ an object surface, prohe signal fluctuations generated by speckle effects. power vanation of a light source, electronic noises, and so on. Previous models of OTDSs can not show reasonable behavior as change of surface inclination and shape of light intensity distribution on the detector. In this paper, we propose a new and reasonable modeling for diffise-type OTDSs based on a geometrical optics. To verify propriety of new modeling, we take basic experiments. Shape of light intensity distribution is asymmetric in both simulation result and experimental result. Both simulation result and experimental result show same tendency of light intensity distribution movement as changing surface inclination

• Journal of computational fluids engineering
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• v.14 no.3
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• pp.9-15
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• 2009

Numerical investigation has been carried out for laminar flow past an inclined square cylinder in cross freestream. In particular, inclination of a square cylinder with respect to the main flow direction can cause sudden shift of the separation points to other edges, resulting in drastic change of flow-induced forces on the cylinder such as Strouhal number (St) of vortex shedding, drag and lift forces on the cylinder, depending upon the inclination angle. Collecting all the numerical results obtained, we propose contour diagrams of drag/lift coefficients and Strouhal number on an Re-Angle plane. This study would be the first step towards understanding flow-induced forces on cylindrical structures under a strong gust of wind from the viewpoint of wind hazards.

• Proceedings of the KSR Conference
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• 2004.10a
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• pp.430-434
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• 2004

The geometric parameters between wheel and rail change wheel/rail contact geometry characteristics, and this influence dynamic behavior of rolling stock. So, the selections of optimum geometric parameters between wheel and rail is important for planning of railway system. In this study, we have analyzed the influence of geometric parameters like wheel flange-back distance, gage, and rail inclination to the equivalent conicity relating dynamic behavior. The analyses show the following results. The widening of wheel flange-back distance increase the equivalent conicity, the widening of gage, rail inclination 1/20 compared with rail inclination 1/40 decrease the equivalent conicity.

• Journal of Auto-vehicle Safety Association
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• v.11 no.1
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• pp.40-47
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• 2019

First, three point bending analysis for the inclined press door impact beam was carried out to investigate inclination angle effect on the maximum strength with varying support distance. Next, for the system model with spring elements representing body stiffness at door mounting area, the bending structural behavior of impact beam mounted on vehicle was estimated. The mounting distance and inclination angle were changed and the beam bending buckling strength was presumed at the head displacement below which spring stiffness change has little effect on the load. Finally strength ratio to predict the bending buckling strength of impact beam mounted on vehicle from three point bending maximum strength of fixed support distance was suggested.