• Journal of the Korean Society of Manufacturing Technology Engineers
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• v.8 no.4
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• pp.29-37
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• 1999

This paper involves the "on-line" measurement of burrs using a capacitance sensor. A non-contact capacitance gauging sensor is attached to an ultra precision milling machine which was used as a positioning system The setup is used to measure burr profiles along machined workpiece edges. Experimental procedures and results as well as the basic theoretical principles of the capacitance sensor and specifications of related equipment are presented. The proposed scheme is shown to be accurate easy to setup and with minor modifications readily applicable to automatic deburring processes.processes.

• Journal of Korea Water Resources Association
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• v.50 no.3
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• pp.211-221
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• 2017

In statistical hydrology, various extreme distributions such as the generalized extreme value (GEV), generalized logistic (GLO) and Gumbel (GUM) models have been widely used to analyze the extreme events. In the case of rainfall events in South Korea, the GEV and Gumbel distributions are known to be appropriate among various extreme distribution models. However, the proper probability distribution model may be different depending on the type of extreme events, rainfall duration, region, and statistical characteristics of extreme events. In this regard, it is necessary to apply a wide range of statistical properties that can be represented by the distribution model because it has two shape parameters. In this study, the statistical applicability of rainfall data is analyzed using the Burr XII distribution and the dimensionless L-moment ratio for 620 stations in South Korea. For this purpose, L-skewness and L-kurtosis of the Burr XII distribution are derived and L-moment ratio diagram is drawn and then the applicability of 620 stations was analyzed. As a result, it is found that the Burr XII distribution for the stations of the Han River basin in which L-skewness is relatively larger than L-kurtosis is appropriate, It is possibility of replacing the distribution of commonly used Gumbel or GEV distributions. Therefore, the Burr XII model can be replaced as an appropriate probability model in this basin.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.11 no.3
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• pp.514-522
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• 2007

Finite failure NHPP models presented in the literature exhibit either constant, monotonic increasing or monotonic decreasing failure occurrence rates per fault. In this parer, Goel-Okumoto and Yamada-Ohba-Osaki model was reviewed, proposes the Burr distribution reliability model, which making out efficiency application for software reliability. Algorithm to estimate the parameters used to maximum likelihood estimator and bisection method, model selection based on SSE, AIC statistics and Kolmogorov distance, for the sake of efficient model, was employed. Analysis of failure using real data set for the sake of proposing shape parameter of the Burr distribution was employed. This analysis of failure data compared with the Burr distribution model and the existing model(using arithmetic and Laplace trend tests, bias tests) is presented.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2009.06a
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• pp.415-416
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• 2009

• Journal of Industrial Technology
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• v.22 no.A
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• pp.37-42
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• 2002

The shearing process for the sheet metal is normally used in the precision elements such as a frame of TFT-LCD or lead frame of IC chips. In these precision elements, the burr formation prevents the system assembly and needs the additional burr removing process. In this study, we have developed the novel ultrasonic deburring system to remove the small burr came from shearing of the sheet metal effectively. The deburring tool is driven by the stepping motor and alumina and SiC particles are used as abrasives. Ultrasonic power and the flowing resistance of the abrasives make ti possible to abrasive the burr.

• Journal of Industrial Technology
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• v.25 no.B
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• pp.121-126
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• 2005

Micro wires manufactured by the straightening process are used in the BT(Bio-Technology), IT(Information-Technology), NT(Nano-Technology). We have developed a novel wire straightener which uses the direct heating method(DHM) for straightening the micro wire and shearing device for burr-less cutting. In this study, we confirm the tendency of micro wire after the shearing process. It is impossible to remove the burr in the shearing process. However, the embodiment of minimum burr size after the shearing process is the best in-process method. In order to minimize the burr size, we have accomplished the various experiment condition such as the U-groove, the effect of the counter punch, the shear angle, clearance.

• Transactions of the Korean Society of Machine Tool Engineers
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• v.13 no.3
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• pp.61-67
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• 2004

In micro hole punching process the burr occurs inevitably, but the burr must be minimized in order to improve the quality and accuracy of the product. In this study, magnetic field-assisted polishing technique is applied to remove the burr which exists in nozzles for ink-jet printer head and proved to be a feasible for deburring by experiment. The deburring characteristics of sheet metals was investigated changing with polishing time and magnetic abrasive size. After the deburring, the burr size has remarkably reduced and roundness of the hole also has improved.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2002.05a
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• pp.740-744
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• 2002

This paper describes the design and development of drills with deburring inserts. The drills can be used to drill holes and deburr the edges of the drilled holes simultaneously. The drills incorporate deburring inserts within the shank. The insert consists of a fixing base, a cantilever spring and a cutting tip. The stiffness of the cantilever spring and the details of the cutting tip play a central role for the successful deburring performance. The deburring performance is also governed by the conditions of the drilling burr best described by the burr control chart suggested by Dornfeld. With careful burr control, successful deburring is obtained by the drills with deburring inserts.

• Journal of Korean Neurosurgical Society
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• v.46 no.6
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• pp.592-595
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• 2009

Cerebellar hemorrhage is an unusual complication of supratentorial neurosurgery. To the best of our knowledge, only three case reports have described the occurrence of cerebellar hemorrhage after burr hole drainage for the treatment of chronic subdural hematoma (SDH). We present the case of a patient with this rare postoperative complication of cerebellar hemorrhage after burr hole drainage of a chronic SDH. Although burr hole drainage for the treatment of chronic SDH is rare complication, it is necessary to be aware of the possibility of cerebellar hemorrhage after supratentorial surgery, even with limited surgery such as burr hole drainage of a chronic SDH.

• Journal of the Korean Society of Safety
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• v.13 no.2
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• pp.164-169
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• 1998

Burrs can be formed on the feed marks ridges as well as on the edges of the machined parts in machining operations. These burrs are undesirable in terms of the surface quality, the precise dimensioning of machined parts and the safety of operators. This paper experimentally investigates the sideward burr formation in 3-dimensional cutting. In particular, the experimental relationships between the size of sideward burr and the cutting parameters are established and suggestions are made for minimizing sideward burr formation.