• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 1991년도 한국자동제어학술회의논문집(국내학술편); KOEX, Seoul; 22-24 Oct. 1991
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• pp.1155-1160
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• 1991

Active part mating algorithm using 6-axis force sensor data for the assembly automation and/or teletobotics is presented and experimented. Parts to be mated are cylindrical and have no chamfers. There are basically two modes. One is the normal mode with only a positional error, the other is the tilted mode with an orientational error in addition to a positional error. The used algorithm distinguishes a contact external to the hole from that of internal to the hole in order to perform part-mating in spite of the relative tilt between the hole and the peg.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 1999년도 하계종합학술대회 논문집
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• pp.627-630
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• 1999

For depth extraction from the focus and recovery the shape, determination of criterion function for focus measure and size of the criterion window are very important. However, Texture, illumination, and magnification have an effect on focus measure. For that reason, depth map has a partial high and low peak. In this paper, we propose a depth extraction method from focused images using the error interpolation. This method is modified the error depth into mean value between two normal depth in order to improve the depth map.

• Communications for Statistical Applications and Methods
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• 제16권4호
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• pp.675-686
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• 2009

In this paper, it will be assumed that there are two distinct populations which are multivariate normal with equal covariance matrix. We also assume that the two populations are equally likely and the costs of misclassification are equal. The classification rule depends on the situation when the training samples include missing values or not. We consider the bootstrap confidence intervals for classification error rate when a block of observation is missing.

• Journal of the Korean Statistical Society
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• 제34권4호
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• pp.345-366
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• 2005

This paper considers the cointegrating vector estimator in the error correction model with stationary covariates, which combines the stationary vector autoregressive model and the nonstationary error correction model. The cointegrating vector estimator is shown to follow the locally asymptotically mixed normal distribution. The variance of the estimator depends on the co­variate effect of stationary regressors, and the asymptotic efficiency improves as the magnitude of the covariate effect increases. An economic application of the money demand equation is provided.

• Journal of Radiation Protection and Research
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• 제31권1호
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• pp.17-23
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• 2006

본 연구의 목적은 바이오어쎄이 측정오차의 통계적 분포가 섭취량 추정값에 미치는 영향을 분석하여 오차의 분포를 선정하는데 필요한 기준을 제시하는데 있다. 이를 위하여 본 연구에서는 오차가 정규분포와 대수정규분포를 따른다고 가정한 경우에 대해 최대우도법을 사용하여 섭취량을 평가하였고 그 결과를 서로 비교해 보았다. 본 연구의 결과에 따르면, 검출한도보다 약간 높은 값을 갖는 폐 잔류량 측정결과의 경우 두 분포사이에서의 차는 거의 무시할 수 있을 정도로 작게 나타났다. 그러나 일일 소변 배설률에 대한 측정결과의 경우 오차가 대수정규분포를 따른다고 가정하였을 때의 결과가 정규분포를 따른다고 가정하였을 때의 결과보다 거의 10 % 정도 높게 평가되었다. 이러한 사실로 비추어 볼 때 불착도 요소가 계측통계 오차에 주로 기인되는 경우 오차의 분포가 섭취량 추정값에 거의 영향을 미치지 않는 것으로 사료되나, 불확도 요소에서 그 이외의 오차가 지배적인 경우에는 대수정규분포를 가정하여 섭취량을 추정하는 것이 바람직하다고 판단된다.

• Imaging Science in Dentistry
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• 제36권1호
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• pp.41-48
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• 2006

Purpose : To evaluate the reliability and clinical usefulness of ultrasonography in the temporomandibular joint (TMJ). Materials and Methods : Parasagittal and paracoronal 1.5 T MR images and 7.5 MHz ultrasonographs of 40 TMJs in 20 asymptomatic volunteers were obtained. Disc position using MR imaging was evaluated and the distance between the lateral surface of mandibular condyle and the articular capsule using MR image and ultrasonograph of 27 TMJs with normal disc position was measured and compared. Intraobserver and interobserver measurements reliability was evaluated by using interclass correlation coefficients (ICC) and measurement error. Also, the distance measured on ultrasonographs was compared, according to mouth position and disc postion. Results : The normal disc position was found in 27 of 40 asymptomatic joints. At the intraobserver reliability of measurement, ICC at the closed and open mouth position were 0.89 and 0.91. The measurement error was 0.4% and 0.5%. At the interobserver reliability, ICC at the closed and open mouth position were 0.92 and 0.81. The measurement error was 0.4% and 0.7%. At the TMJ with normal disc position, the distances between the lateral surface of mandibular condyle and the articular capsule measured on MR images and ultrasonographs were $2.0{\pm}0.7mm,\;1.8{\pm}0.5mm$, respectively (p<0.05). On the ultrasonographs, the distances at open mouth position were $1.2{\pm}0.5mm$ (p<0.05). At the TMJ with medially displaced disc, the distances at the closed and open mouth position were $1.3{\pm}0.3\;mm\;and\;0.9{\pm}0.2\;mm$ (p<0.05). Conclusion : The results suggest ultrasonography of TMJ is a reliable imaging technique for assessment of normal disc position.

• International Journal of Aeronautical and Space Sciences
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• 제1권1호
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• pp.70-80
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• 2000

The attitude knowledge error model is formulated for specifically KOMPSAT attitude determination system using the Lefferts/Markley/Shuster method, and the attitude determination(AD) error analysis is performed so as to investgate the on-board attitude determination capability of KOrea Multi-Purpose SATellite(KOMPSAT) using the covariance analysis method. Analysis results show there is almost no initial value effect on Attitude Determination (AD) error and the sensor noise effects on AD error are drastically decreased as is predicted because of the inherent characteristic of Kalman filter structure. However, it shows that the earth radiance effect of IR-sensor(earth sensor) and the bias effects of both IR-sensor and fine sun sensor are the dominant factors degrading AD error and gyro rate bias estimate error in AD system. Analysis results show that the attitude determination errors of roll, pitch and yaw axes are 0.056, 0.092 and 0.093 degrees, respectively. These numbers are smaller than the required values for the normal mission of KOMPSAT. Also, the selected on-orbit data of KOMPSAT is presented to demonstrate the designed AD system.

• 한국기계가공학회지
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• 제11권5호
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• pp.42-47
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• 2012

Construction equipment is heavily loaded during normal operation. In recent years, there is a trend that lower gear noise levels are demanded for drivers to avoid annoyance and fatigue during operation. For articulated hauler's final drive, meshing transmission error(T.E.) is the excitation that leads the tonal noise known as gear whine, and radiated gear whine is also the dominant source of noise in the whole gearbox. This paper presents a method for the analysis of the tooth profile modification, and the prediction of transmission error under the loaded torques for the spur gear pair of the articulated hauler's final drive. And the transmission error, transmission error harmonics and contact stress are also calculated and compared before and after tooth modification under one torque. The simulation result shows that the transmission error and contact stress under the loads can be minimized by the appropriate tooth profile modification.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2003년도 추계학술대회
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• pp.1775-1780
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• 2003

A hybrid finite element analysis was used to analyze the influence of ring gear rim thickness and spline number on the static properties of an epicyclic gear system with manufacturing errors. Both of these parameters affected the bearing force and critical stress. The effect of changes in the rim thickness on the load sharing between the gears depended on the type of manufacturing error. Ring flexibility improved the load sharing between planetary gears only in systems with planet tooth thickness or planet tangential errors; for other types of error, ring flexibility worsened the load sharing. To improve load sharing, rim thickness and spline number should be controlled within a specific range. The effect of the ring gear boundary condition was more apparent in a system with errors than in a normal system.

• 한국농공학회지
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• 제18권1호
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• pp.4021-4037
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• 1976

This paper describes the actual experiments of the error propagation and studies of analytical photogrammetry using the simulation method in which we can find the causes of the errors. These studies and the results give the valuable data which are very effective for systematically controlling the errors in aerial triangulation. The main contents in my paper are as follows: 1. Dose the scale errors in the successive models in the form of normal distribution appear when the observation errors propagate in the form of normal distribution\ulcorner 2. In what form does this scale error propagation in the actual model appear\ulcorner 3. When the causes of the scale error propagation are found, is the evaluation standard determined normally\ulcorner 4. What degree of influence is there form the constant errors\ulcorner I have done several experiments using the simulation method technique to solve the complicated error propgation of aerial triangulation which is the effective means to research the relations between cause and effect. In this paper, the studies have concentrated on the following points of simulation experiments. (1) The first part descries how we can produce the soft program of the simulation experiment. (2) The second part is the method propagating the errors in the simulation models and the kinds of errors. (3) The final part is the most important; that is the analyzing and evaluation of control during actual work. From the above-mentioned points, it is said that these studies are a very important development in the field of controlling and managing aerial photogrammetry and especially in the case of error propagation, we can clearly find the causes of the errors and steps and parts of errors generated when we use these techniques.