• Transactions of Materials Processing
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• v.6 no.5
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• pp.400-407
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• 1997

Geometric mapping technique has been used to find the shape of initial blank for sheet forming. The method was chosen because of its simplicity and numerical efficiency. Error in blank shape were measured along deformation path by FE analysis of forming. Blank shape was modified by volume additionaddition/Subtractiontraction method with taking with taking into account of deformation path. Modified blank shape shows an acceptable result, showing the current method can be an useful tool for predicting blank shape in the practical application. More test will be done to verify the validity of the method.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.11 no.3
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• pp.104-109
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• 2012

Recently, the deburring process which is last process of manufacture is one of the important process for complete product. The manual deburring process can cause not only higher error rate but also irregular shape and quality of product. Therefore, Shape Guided Automatic Deburring Machine has been developed to resolve the above problems. But the Shape Guided Automatic Deburring Machine have been applied only to produce a circular product. Therefore, this machine is difficult to apply to products of various shapes. To solve this problem, we would like to develop Generalized Shape Guided Automatic Deburring Machine applicable to various shapes. To this end, we have done the modeling and design using CATIA program and have performed machine simulation.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2003.06a
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• pp.443-446
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• 2003

The vibration mode shape changed by the phase angle that can be controlled by phase-shifting ESPI system is discussed. For the phase-shifting ESPI experiment the stroboscopic illumination by using AOM(Acousto-Optic Modulator) is needed, and the initial phase angle can be adjusted by the program. The vibration mode shape is changed when the initial phase angle is changed. We examined the vibration mode shape change due to the initial phase angle change at each resonance frequency. Through this study, we found that in the vibration testing using phase-shilling ESPI the vibration mode shape is improved in the quality by adjusting exact phase angle and the error of the quantitative vibration analysis can be reduced.

• Journal of Korea Multimedia Society
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• v.16 no.9
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• pp.1018-1030
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• 2013

The corpus callosum is the largest connective structure in the brain, and its shape and size are correlated to sex, age, brain growth and degeneration, handedness, musical ability, and neurological diseases. Manually segmenting the corpus callosum from brain magnetic resonance (MR) image is time consuming, error prone, and operator dependent. In this paper, two semi-automatic segmentation methods are present: the active contour model-based approach and the active shape model-based approach. We tested these methods on an MR image of the human brain and found that the active contour approach had better segmentation accuracy but was slower than the active shape approach.

• Proceedings of the KSRS Conference
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• 2003.11a
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• pp.882-884
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• 2003

We present an application of digital video images for object tracking. In order to track a fixed object, which was shoot on a moving vehicle, this study develops a shape-based matching algorithm to implement the tracking task. Because the shape-based matching algorithm has scale and rotation invariant characteristics, therefore it can be used to calculate the similarity between two variant shapes. An experiment is performed to track the ship object in the open sea. The result shows that the proposed method can track the object in the video images even the shape change largely.

• Journal of the Korea Convergence Society
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• v.8 no.5
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• pp.185-192
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• 2017

Machine tool errors can be divided into geometric error, thermal deformation error, and machining error. In this study, the influence of each error on the total error and the relative size of each error are quantitatively analyzed in 2D machining. The thermal deformation error and the machining error caused a relatively large error compared to the geometric error, which is directly related to the machining accuracy. In order to eliminate the error factors, the possibility of error compensation was examined by analyzing the measured error profile shape. As a result, about 40 ~ 50% error compensation was achieved for each error factor. Through this study, it is possible to construct a basic data base on machining, and it is expected that it will be able to compensate the machining error from the viewpoint of users.

• Communications for Statistical Applications and Methods
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• v.14 no.1
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• pp.33-55
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• 2007

The economic world is full of patterns, many of which exert a profound influence over society and business. One of the most contentious is the distribution of wealth. Way back in 1897, an Italian engineer-turned-economist named Vilfredo Pareto discovered a pattern in the distribution of wealth that appears to be every bit as universal as the laws of thermodynamics or chemistry. The present paper proposes some Bayes estimators of shape parameter of Pareto income distribution in censored sampling. Asymmetric LINEX loss function has been considered to study the effects of overestimation and underestimation. For the prior distribution of the parameter involved a number of priors including one and two-parameter exponential, truncated Erlang and doubly truncated gamma have been contemplated to express the belief of the experimenter s/he has regarding the parameter. The estimators thus obtained have been compared theoretically and empirically with the corresponding estimators under squared error loss function, some of which were reported by Bhattacharya et al. (1999).

• Communications for Statistical Applications and Methods
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• v.27 no.1
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• pp.47-64
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• 2020

In this paper, we derive some estimators of the scale parameter of the exponentiated half-logistic distribution based on the multiply Type-I hybrid censoring scheme. We assume that the shape parameter λ is known. We obtain the maximum likelihood estimator of the scale parameter σ. The scale parameter is estimated by approximating the given likelihood function using two different Taylor series expansions since the likelihood equation is not explicitly solved. We also obtain Bayes estimators using prior distribution. To obtain the Bayes estimators, we use the squared error loss function and general entropy loss function (shape parameter q = -0.5, 1.0). We also derive interval estimation such as the asymptotic confidence interval, the credible interval, and the highest posterior density interval. Finally, we compare the proposed estimators in the sense of the mean squared error through Monte Carlo simulation. The average length of 95% intervals and the corresponding coverage probability are also obtained.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.16 no.11
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• pp.1132-1142
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• 1991

This paper proposed a method of feature parameter extraction for shape information analysis of moving object. In the 2-D plane, moving object are extracted by the difference method. Feature parameters of moving object are chosen area, perimeter, a/p ratio, vertex, x/y ratio. We changed brightness variation from the range of 600Lux to the 1400Lux and then determined Permissible Error range of feature parameter due to the brightness variation. So as to verify the validity of proposed method, experiment are performed with a toy car and it's results showed that decision error was less than 6%.

• Journal of the Korean Society for Precision Engineering
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• v.17 no.3
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• pp.174-183
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• 2000

Non-Parallelism the axial direction occurs during grinding process of long slender shafts. The reason for the axial error is due to elastic deformation of the components, accumulation phenomenon of the grinding and wheel wear during the grinding process. The accumulation phenomenon, the size generation mechanism and the wheel wear process during traverse grinding result in complicated process at each step on the wheel surface. The grinding system stiffness obtained from the stiffness of the center on the tailstock and the workpiece varing according to the relative position of the wheel and the workpiece. Further more, the value of wheel wear increases as the grinding process advances. The above mentioned issues make the shape generation process during traverse grinding quite complicated. This research analyzes the shape generation process in the direction of the work spindle. First, the formulation of the grinding system stiffness was conducted and the simulation analysis method of the traverse grinding was established. Also, a measuring system for assessing the dimensinal accuracy of the workpiece has been developed.