• Proceedings of the KSME Conference
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• 2004.11a
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• pp.743-748
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• 2004

In this paper, an analysis on a new robot manipulator developed for the side buffing of the shoes is presented. The robot is composed of five D.O.F. An Analysis on the forward and inverse kinematics was performed. The hardware system including electric wirings, control system, and related system was developed. Also, The teleoperating communication system was developed to shake with other related system Computer programs to track the bonding line of shoes were developed. An user-friendly graphic program was developed using C $^{++}$ language for the users.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2004.10a
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• pp.359-363
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• 2004

Numerous studies have been performed to analyze various phenomena of human's walking, gait. In the present study, unrecognized walking and recognized walking were analyzed by three dimensional motion capture system(VICON motion system Ltd., England) and simulated by computer program. Two normal males participated in measuring the motion of unrecognized and recognized walking. Six infrared cameras and four force plates were used and sixteen reflective markers were attached to the subject to capture the motion. A musculoskeletal model was generated anatomically by using ADAMS(MSC software corp., USA) and LifeMOD(Biomechanics Research Group Inc, USA). The inverse dynamic simulation and forward dynamic simulation were also performed. The result of simulation was similar to the experimental result. This study provides the base line for dynamic simulation of the falling walking. It will be useful to simulate various another pathologic gaits for old peoples.

• Transactions of the Korean Society of Mechanical Engineers
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• v.17 no.1
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• pp.223-235
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• 1993

VTR(Video Tape Recorder) has very complicated mechanisms composed of various cams, links, gears and so on. To satisfy kinematic requirements of VTR components, various geometric constraints between rigid bodies and a translational cam design program are developed. Mechanisms of VTR are divided into functional groups like a control part, a loading part and a tape guide part. Each group is modeled for kinematic and dynamic analysis. Finally, all groups are combined together for a complete VTR model and loads required for each function of VTR controls are studied. Detailed description of developed programs are presented and result are discussed.

• Journal of Korean Society on Water Environment
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• v.37 no.6
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• pp.520-530
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• 2021

Multivariate statistical analysis and an environmental hydrological model were applied for investigating the causes of water pollution and providing best management practices for water quality improvement in urban and agricultural watersheds. Principal component analysis (PCA) and cluster analysis (CA) for water quality time series data show that chemical oxygen demand (COD), total organic carbon (TOC), suspended solids (SS) and total phosphorus (T-P) are classified as non-point source pollutants that are highly correlated with river discharge. Total nitrogen (T-N), which has no correlation with river discharge and inverse relationship with water temperature, behaves like a point source with slow and consistent release. Biochemical oxygen demand (BOD) shows intermediate characteristics between point and non-point source pollutants. The results of the PCA and CA for the spatial water quality data indicate that the cluster 1 of the watersheds was characterized as upstream watersheds with good water quality and high proportion of forest. The cluster 3 shows however indicates the most polluted watersheds with substantial discharge of BOD and nutrients from urban sewage, agricultural and industrial activities. The cluster 2 shows intermediate characteristics between the clusters 1 and 3. The results of hydrological simulation program-Fortran (HSPF) model simulation indicated that the seasonal patterns of BOD, T-N and T-P are affected substantially by agricultural and livestock farming activities, untreated wastewater, and environmental flow. The spatial analysis on the model results indicates that the highly-populated watersheds are the prior contributors to the water quality degradation of the river.

• Journal of Ocean Engineering and Technology
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• v.27 no.3
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• pp.61-66
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• 2013

This paper presents the results of finite element simulations of elastic wave propagation in an underwater steel plate and the verification of a proposed method utilizing elastic wave-based damage detection. For the simulation and verification, we carried out the following procedures. First, three-dimensional finite element models were constructed using a general purpose finite element program. Second, two types of damages (mechanical defects and deteriorations) were applied to the underwater steel plate and three parameters (defect location, defect width, and depth) were considered to adjust the severity of the applied damages. Third, elastic waves were generated using the oblique incident method with a Gaussian tone burst, and the response signals were obtained at the receiving point for each defect or deterioration case. In addition, the received time domain signals were analyzed, particularly by measuring the magnitudes of the maximum amplitudes. Finally, the presence and severity of each type of damage were identified by the decreasing ratios of the maximum amplitudes. The results showed that the received signals for the models had the same global pattern with minor changes in the amplitudes and phases, and the decreasing ratio generally increased as the damage area increased. In addition, we found that the defect depth was more critical than the width in the decrease of the amplitude. This mainly occurred because the layout of the depth interfered with the elastic wave propagation in a more severe manner than the layout of the width. An inverse analysis showed that the proposed method is applicable for detecting mechanical defects and quantifying their severity.

• Imaging Science in Dentistry
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• v.53 no.1
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• pp.43-51
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• 2023

Purpose: This study aimed to assess texture analysis(TA) of cone-beam computed tomography (CBCT) images as a quantitative tool for the differential diagnosis of odontogenic and non-odontogenic maxillary sinusitis(OS and NOS, respectively). Materials and Methods: CBCT images of 40 patients diagnosed with OS (N=20) and NOS (N=20) were evaluated. The gray level co-occurrence (GLCM) matrix parameters, and gray level run length matrix texture (GLRLM) parameters were extracted using manually placed regions of interest on lesion images. Seven texture parameters were calculated using GLCM and 4 parameters using GLRLM. The Mann-Whitney test was used for comparisons between the groups, and the Levene test was performed to confirm the homogeneity of variance (α=5%). Results: The results showed statistically significant differences(P<0.05) between the OS and NOS patients regarding 3 TA parameters. NOS patients presented higher values for contrast, while OS patients presented higher values for correlation and inverse difference moment. Greater textural homogeneity was observed in the OS patients than in the NOS patients, with statistically significant differences in standard deviations between the groups for correlation, sum of squares, sum of entropy, and entropy. Conclusion: TA enabled quantitative differentiation between OS and NOS on CBCT images by using the parameters of contrast, correlation, and inverse difference moment.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.30 no.3A
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• pp.317-328
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• 2010

The method to evaluate the flexural capacity of steel fiber-reinforced ultra high strength concrete beams was proposed in this study. An experimental program was set up and fourteen beams have been tested. Test results were compared with predictions by design code and by the proposed method, respectively. It was found that predictions by using ACI 544 Committee recommendations considerably underestimate the flexural capacity. Underestimation of flexural capacity resulted from that of tensile stress block. Three-point bending test data of notched prism specimens and their inverse analysis results were incorporated into modeling of tension stress block. The ratio of the predicted to the experimental flexural capacity was in the range of 0.98 to 1.14. The present study represents that the proposed method allows more realistic prediction of flexural capacity of steel fiber-reinforced ultra high strength concrete beams.

• Journal of Biosystems Engineering
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• v.28 no.1
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• pp.65-76
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• 2003

The analysis of cow body parameters is important to provide some useful information fur cow management and cow evaluation. Present methods give many stresses to cows because they are invasive and constrain cow postures during measurement of body parameters. This study was conducted to develop the stereo vision system fur non-invasive analysis of cow body features. Body feature parameters of 16 heads at two farms(A, B) were measured using scales and nineteen stereo images of them with walking postures were captured under outdoor illumination. In this study, the camera calibration and inverse perspective transformation technique was established fer the stereo vision system. Two calibration results were presented for farm A and fm B, respectively because setup distances from camera to cow were 510 cm at farm A and 630cm at farm B. Calibration error values fer the stereo vision system were within 2 cm for farm A and less than 4.9 cm for farm B. Eleven feature points of cow body were extracted on stereo images interactively and five assistant points were determined by computer program. 3D world coordinates for these 15 points were calculated by computer program and also used for calculation of cow body parameters such as withers height. pelvic arch height. body length. slope body length. chest depth and chest width. Measured errors for body parameters were less than 10% for most cows. For a few cow. measured errors for slope body length and chest width were more than 10% due to searching errors fer their feature points at inside-body positions. Equation for chest girth estimated by chest depth and chest width was presented. Maximum of estimated error fur chest girth was within 10% of real values and mean value of estimated error was 8.2cm. The analysis of cow body parameters using stereo vision system were successful although body shape on the binocular stereo image was distorted due to cow movements.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.4 no.5
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• pp.971-976
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• 2000

The main objective of this paper is to present the rain cell size distribution observed during squall line episodes in the Sudano-Sahelian region. The used data were collected during the EPSAT Program [Etude des Precipitation par SATellite (Satellites Study of Precipitation)] which has been developed since 1958, on an experimental area located near Niamey, Niger (2 10′32"E, 13 28′38"N). The data were obtained with a C-band radar and a network composed of approximately 100 raingages over a 10,000 $\textrm{km}^2$. In this work a culling of the squall line episodes was made for the 1992 rainy season. After radar data calibration using the raingage network a number of PPI (Plan Position Indicator) images were generated. Each image was then treated in order to obtain a series of radar reflectivity (Z) maps. To describe the cell distribution, a contouring program was used to analyze the areas with rain rate greater than or equal to the contour threshold (R$\geq$$\tau$). 24700 contours were generated, where each iso-pleth belongs to a predefined threshold. Computing each cell surface and relating its area to an equi-circle (a circle having the same area as the cell), a statistical analysis was made. The results show that the number of rain cells having a given size is an inverse exponential function of the equivalent radius. The average and median equivalent radii ate 1.4 and 0.69 In respectively. Implications of these results for the precipitation estimation using threshold methods are discussed.

• The Korean Journal of Emergency Medical Services
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• v.18 no.1
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• pp.95-106
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• 2014

Purpose : This study was attempted to check the correlation between job satisfaction and turnover intention and to provide the basic information to increase job satisfaction of fire fighters. Methods : A total of 369 questionnaires were distributed and 354 questionnaires were filled out and collected for analysis. Results : There was difference in turnover intention by general characteristics. According to position, group of Fire lieutenant or more is lower than that of Fire sergeant or less (F=3.61, p=.014). The group of rescue & emergency service and administration was significantly lower than other groups(F=4.84, p=.001). In pattern of duties, day service group was significantly lower than shift work group in .05 level(t=2.59, p=.022). Finally, in the correlation, the more job satisfaction increase, the more turnover intention decrease that represents inverse correlation between job satisfaction and turnover intention(r=-.523, p <.001). Namely, it represents the results that the higher job satisfaction is low turnover intention. Conclusion : More studies of fire officer in other cities are required to generalize the results. We have to develop program for job satisfaction for fire officer firstly, because program for job satisfaction used in this study was not developed for fire fighters.