• 제어로봇시스템학회:학술대회논문집
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• 1996.10b
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• pp.676-679
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• 1996

In this paper, the uniform observability and the error characteristics for stationary SDINS error are analyzed. The use of the Lyapunov transformation is proposed for transforming te conventional SDINS error model and the sufficient conditions for the uniform observability of SDINS error model are analytically derived. A complete characterization for the SDINS error characteristics during two position alignment is presented which allows us to predict the performance of two position alignment in SDINS.

• Journal of the Ergonomics Society of Korea
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• v.30 no.1
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• pp.109-115
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• 2011

In this research, three topics were studied for the elderly. The first was the elderly's error characteristics for tracing task and the second was for depth perception. The characteristics were compared with the young's. Twenty two old people and twenty two young people participated in the tracing experiment, respectively. In the depth perception experiment, twenty three old people and twenty two young people participated. A depth perception apparatus and a tracing one were used in the experiment. In the depth perception error, a significant difference was not detected on gender. However significant differences were detected with age and viewing distance. In the tracing error, significant difference was detected with age, also. The third experiment was push-button operation and fifteen old people participated in the experiment. As the result, operation time error was increased with the button size and the moving distance. The result of this study will be able to be considered in its user interface design to reduce the elderly's error while using a product.

• Journal of Korean Institute of Industrial Engineers
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• v.17 no.2
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• pp.97-105
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• 1991

In developing a regression relationship for a standard data system in work measurement, job characteristics are frequently measured with error when measurements are made in the field under less controlled conditions or when accurate instruments are not available. This paper concerns with the prediction of the total task time when job characteristics are measured with error. Integrated mean square error of prediction(IMSE) is developed as a measure of the effect of errors in job characteristics on the predicted total task time. By evaluating how IMSE is affected by the measurement error in each job characteristic, we can determine which error should be controlled to develop a desirable standard data system.

• Journal of the Korean Society of Safety
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• v.13 no.4
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• pp.279-285
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• 1998

This study investigated human error characteristics of the 42 fatal industrial accidents reported by staff members of Korea Industrial Safety Corporation. Various types of human error were judged to be primary contributing factors in about 74 percent of the cases. Most of human error made by involved industrial operators resulted from two types of mistakes: (1) mistake in judgement of work situation, and (2) omission in daily check. It was concluded that preparation/observance for work procedure manuals, danger predication training and enforcement/Education of daily check routine would be effective preventive tools for these types of human error attributable to fatal industrial accidents.

• Journal of Urban Science
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• v.7 no.1
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• pp.45-54
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• 2018

The purpose of this study is to find the factors that reduce prediction error in traffic volume using highway traffic volume data. The ARIMA model was used to predict the day, and it was confirmed that weekday and weekly characteristics were distinguished by prediction error. The forecasting results showed that weekday characteristics were prominent on Tuesdays, Wednesdays, and Thursdays, and forecast errors including MAPE and MAE on Sunday were about 15% points and about 10 points higher than weekday characteristics. Also, on Friday, the forecast error was high on weekdays, similar to Sunday's forecast error, unlike Tuesday, Wednesday, and Thursday, which had weekday characteristics. Therefore, when forecasting the time series belonging to Friday, it should be regarded as a weekly characteristic having characteristics similar to weekend rather than considering as weekday.

• Journal of the Korea Safety Management & Science
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• v.14 no.4
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• pp.85-91
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• 2012

To verify the effect of driver's personal characteristics of driver on the accident frequency through railway accidents caused by human errors and the relationship with aptitude test. To prove the relevance between the driver's personal characteristics and human error accidents. Accident data from 2010 to 2011 was analyzed which collected from a train crew department in K national corporation, and 31 drivers gave an personal interview from Sep. 2011 to Nov. 2011 who had controlled a train alone and caused an accident. Compared between driver's personal characteristics and accident rate, and accident induction possibility surveyed from normal person and disqualified in aptitude tests. Accidents was occurred with the age 40s (27%) and 50s (25%), and with the experience between 15 years and 20 years (38%) and over 20 years (30%). Because more aged, more experienced, it can be seen in the correlation between driver's age and accidents induction caused by human errors like illusion. First of all it must be checked whether working conditions and environmental factors are human error-prone. Most accidents occur when received civil complaints or manager at the riding. Therefore accidents can be prevented when investigated through subsequent surveys how often human error happens, even though no accident, and safety device installed based on the error frequency.

• Transactions of the Korean Society for Noise and Vibration Engineering
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• v.11 no.8
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• pp.364-373
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• 2001

The gear whine noise of vehicle transmission is directly correlated tilth the gear transmission error of mating gear The object of this study is to build up the synthesized countermeasure for the reduction of gear whine noire of vehicle transmission by developing the program which can be used to analyze and predict the vibrational characteristics caused by gear transmission error of mating gears of vehicle transmission. The developed mathematical models on the elements of transmission, for example, helical gear pairs, bearings and shafts are used and the modeling of the excitation forces are developed by the gear transmission error of mating gear which is defined by the amount of the elastic deformation of gear tooth & shaft and gear profile & lead errors. The mathematical system model of vehicle transmission developed by the substructure synthesis method Is also verified by the experiments.

• Journal of the Korea Institute of Military Science and Technology
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• v.9 no.1 s.24
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• pp.99-108
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• 2006

In this paper, we analyzed the characteristics of emitter geolocation coverage area within which the emitter lies with a specified probability based on the LOBs(Line of Bearing) of sensors. Stansfield and MSD algorithms were applied to calculate BPE(Best Point Estimate), EEP(Elliptical Error Probable) and CEP(Circular Error Probable), They used the weighting factors composed of ${\sigma}_{Phi}$ (bearing error), QF(quality factor), $P_{e}$ (probability being inside) to optimize the performance. The characteristics of EEP was investigated in the change of them and those of CEP was analyzed based on the deployment of sensors.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.32 no.3
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• pp.235-240
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• 2008

The large size electromagnetic flowmeter was tested to investigate the variation of its error characteristics in the range of low velocity under 0.6 m/s using flowmeter calibration system. For the two case of valve opening rate 100 % and 50 %, these tests were undertaken three times each for twelve velocity condition from $0.05\;^m/s\;to\;0.6\;^m/s$ with increment of $0.05\;^m/s$. It is shown that error characteristic of electromagnetic flowmeter was stabilized within ${\pm}0.4%$ of rate both higher than $0.25^m/s$ of velocity condition and 50 % of valve opening position. But, measurement deviation of flowmeter for ${\Phi}400mm\;and\;{\Phi}600mm$ was out of expected deviation range. It is necessary to correction with calibration. In conclusion, error characteristic of electromagnetic flowmeter wasn't changed proportion to its size.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 1997.04a
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• pp.905-909
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• 1997

A geometric error of machine parts is one of the most important factors that affect the accuracy of positioning, generating and measuring for precision machinery. It is known that the thermal deformation of a workpiece during surface grinding is the most important in the geometric error of ground surface. This paper experimentally describes the grinding characteristics of creep-feed grinding. The wheels have 6 slotted pieces in order to compare the grinding temperature with the geometric.