• Transactions of the Korean Society of Mechanical Engineers A
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• v.26 no.10
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• pp.2194-2200
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• 2002

Transmission error is highly related to gear noise. In order to predict the helical gear noise, transmission error analysis is needed. Up to now, the studies for the transmission error were conducted by the modeling of helical gears only. However, since helical gears are supported by the shaft and bearing, transmission error has the effects of the elements. In this study, the procedure to consider the shaft deformation with bearing stiffness for the transmission error analysis is proposed. To do so, the relationship between gear error and shaft deformation is analytically derived. Shaft deformation with bearing stiffness is analyzed by FEM. It is measured in the experimental test rig by the non-contact displacement sensors. Using the tooth error from tooth modification and the shaft deformation, the effects of shaft on the loaded transmission error are investigated.

• Journal of Oriental Neuropsychiatry
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• v.9 no.2
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• pp.45-51
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• 1998

Purpose : This study has an experiment on finding how Hyangbujapamultang advanced the learning and memory of rat to find the method to improve the failure of memory which is the symptom of dementia.Method : In the experiment, rats were divided the control group (14 rat) which medicate the excipient into the sample group (17 rat) which medicates Hyangbujapalmutang. And the learning ability test and the memorv test was practiced to using the task of radial arm maze.The learning ability test had the presupposition that, when a rat which frequents 8 tracks makes am error not exceeding one time for 3 days without a break, it passes the test.First experiment compared total days when the control group passed the test with total days when the sample group it.The memory test practiced after 24 hours when the learning ability test was over. When a rat frequents 4 tracks, the gates is cut off during 30 seconds. Here the number of error at the control group with that of the sample group.Result: In the learning ability test, the sample group needed 5.82${\pm}$0.37 days to pass the test and the control group needed 6.43${\pm}$0.67 days. In the memory test, the sample group errored 0.29${\pm}$0.37 times and the control group errored 1.86${\pm}$0.78 times.Conclusion : In the learning ability test, the sample group passed the test earlier than the control group, but any statistical correlationship couldn't be found in it. In the memory test, the sample group had the pregnant reduction of the number of error in comparison with the control group.

• Phonetics and Speech Sciences
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• v.10 no.3
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• pp.31-39
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• 2018

This paper aims to present a taxonomy of non-standard words (NSW) for developing a French text normalization system and to propose a method for evaluating this system based on a corpus. The proposed taxonomy of French NSWs consists of 13 categories, including 2 types of letter-based categories and 9 types of number-based categories. In order to evaluate the text normalization system, a representative test set including NSWs from various text domains, such as news, literature, non-fiction, social-networking services (SNSs), and transcriptions, is constructed, and an evaluation equation is proposed reflecting the distribution of the NSW categories of the target domain to which the system is applied. The error rate of the test set is 1.64%, while the error rate of the whole corpus is 2.08%, reflecting the NSW distribution in the corpus. The results show that the literature and SNS domains are assessed as having higher error rates compared to the test set.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2002.05a
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• pp.90-93
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• 2002

In view of reliability assessment, the failure mode analysis by performance tests for machine totals is researched in this study. First, the error analysis with circular movement test data is studied. The various errors and their origins are analyzed by error equations and related parts are investigated. Second, This paper deals with analysis of vibration testing fur machine tools spindle. The various frequency components are classified by FFT and order analysis. The simple measuring devices and error evaluation programs for tests are also developed.

• Journal of Korean Elementary Science Education
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• v.17 no.1
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• pp.47-60
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• 1998

The purpose of this study was to analyze the problem solving strategies of elementary school students and to find out correlations between the functional mental capacity, the perseveration error and the Creature Card Task solving ability. To study this purpose, four categories were selected through pilot test. The sample consisted of 231, the 4th grade students and the 5th grade students in Inchon, Korea and selected 32 students among them. Three instruments were used in this study, Creature Card Task, FIT(Figural Intersection Test) and WCST(Wisconsin Card Sorting Test). Researcher interviewed 32 students about Creature Card Task solving strategies and tests with FIT, WCST. Major findings of the study are as follows: 1. Creature Card Task solving strategies of the selected 4th & 5th grade students were different. Some students solved problems during individual interviews. 2. Creature Card Task solving abilities were significantly correlated with the functional mental capacity and the perseveration error.

• ETRI Journal
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• v.9 no.3
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• pp.3-12
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• 1987

In this paper, a non-classical autocorrelation detector adopting a newly defined test statistic is introduced to solve the typical problem of detecting a narrowband signal transmitted over an additive white Gaussian noise (AWGN) channel. Error probability analyses are performed for a noncoherent frequency-shift-keying (FSK) system employing the proposed test-statistic. Through the histogram approach, the probability density functions of the test-statistics are plotted to explain the analysis model. All numerical results obtained indicate the limited improvement in error performance under the lower signal-to-noise ratio (SNR) and the use of higher number of samples per bit will finally provide the almost same confident potential of improvement in error rate as the system using matched filters (MFs) gives.

• Journal of Institute of Control, Robotics and Systems
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• v.3 no.3
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• pp.289-296
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• 1997

In this paper, a method has been proposed for error measurement/diagnosis of CNC machine tools using the ball link bar on three dimensional space. For the circular motion error measurement, deviation between the desired and actual test path has been measured and analysed using a new type of ball link which incorporates ideal three point contact between reference balls and sockets. Computer program for the error evaluation has been developed and implemented under PC environment. Using the developed program, the circular test data on a CNC machine tool have been analysed, and thus, machine tool errors were effectively evaluated.

• Journal of the Korean Institute of Telematics and Electronics A
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• v.31A no.8
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• pp.111-121
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• 1994

This paper proposes a memory testable code called MTA(Memory TestAble) code which is based on error correcting code technique for testing functional faults in semiconductor memories. The characteristics of this code are analyzed and compared with those of conventional codes. The developed decoding technique for this code can reduce the decoder circuits up to 70% and obtain two-times faster decoding speed than other codes such as hamming code or Hsiao code. The MTA code is eccectively applicable to parallel testing of semiconductor memories because it has the same information length and parity length. It can detect from single error functional faults to triple error in semiconductor memories.

• Journal of the Korean Society of Manufacturing Technology Engineers
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• v.8 no.4
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• pp.19-28
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• 1999

In order to control thermal deformation of the machine origin of machine tools a empirical model and a compensation system have been developed, Prior to empirical modeling the volumetric error considering shape errors and joint errors of slides is formulated through the homogeneous transformation matrix (HTM) and kinematic chain. Simulation results of the HTM method show that the thermal error of the machine origin is more critical than position-dependent errors. In order to make a stable and effective software error compensation system the GMDH (Group Method of Data Handling) models are constructed to estimate the thermal deformation of the machine origin by measuring deformation data and temperature data. A test bar and gap sensors are used to measure the deformation data. In order to compensate the estimated error the work origin shift method is developed by implementing a digital I/O interface board between a CNC controller and an IBM PC. The method shifts the work origin as much as the amounts which are calculated by the pre-established thermal error model. The experiment results for a vertical machining center show that the thermal deformation of the machine origin is reduced within $\pm$5$mu extrm{m}$.

• Proceedings of the Korean Information Science Society Conference
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• 2011.06b
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• pp.313-316
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• 2011

SRAM-based FPGAs are very sensitive to single event upset(SEU) induced by space irradiation. To mitigate SEU effects, space applications employ some mitigation schemes. The triple modular redundancy(TMR) is a well-known mitigation scheme. It uses one or three voters as well as three identical blocks performing the same work. The voters can mask out one error in the outputs from the three replicated blocks. One SEU error in TMRed circuits can be masked but it needs to be detected for some reasons such as to analyze the SEU effects in the satellite or to recover the circuits from the error before additional error occur. In this paper, we developed a fault detection circuit and reporting system to detect a fault on the TMRed circuits. To verify our error detection circuit and reporting circuit, we performed an irradiation test at MC-50 Cyclotron. Experimental results showed that error detection circuit can detect a fault on the TMRed test circuit in radiation environment.