• Journal of Oral Medicine and Pain
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• 제25권2호
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• pp.205-214
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• 2000

This study was performed to investigate the relationship between mandibular midline shift and anteroposterior first molar occlusal relation, and their effects on the mandibular height and the occlusal plane angle. For this study, 49 patients with temporomandibular disorders were selected. They did not show facial asymmetry and their facial midline coincide with maxillary dental midline. Upper and lower mandibular impression were taken and the casts were fabricated. Amount and direction of the mandibular midline shift and the anteroposterior shift between the two occluding first molars were measured on the casts. Several items related to height such as mandibular height from top of the articular surface of the condyle to curve changing point between antegonial notch and mandibular angle, condylar height which was the vertical distance from the articular surface to retroepicondyle of the condyle, and sigmoid height from the deepest point of sigmoid notch to the curve changing point and the occlusal plane angle were also measured on the panoramic and on the transcranial radiographs. Correlation between midline shift and anteroposterior first molar relation and comparison between right and left mandibular height by the midline shift and the first molar relation were analysed by SPSS windows program. The results of this study were as follows : 1. Mean amount of midline shift in the subjects with midline shift were 2.0mm for both side, respectively. The first molar relation of the ipsilateral side of midline shift showed Angle class II tendency and the contralateral side showed Angle class III tendency, which meant drift of the dentition to the side of the midline shift. 2. The occlusal plane angle on the panoramic radiograph were $13.0^{\circ}$ in right, and $12.5^{\circ}$ in left side, and their were no correlation between occlusal plane angle and mandibular midline shift and the first molar occlusal relation. 3. Angle's classification for both sides of the first molar relation were same in about half of all the subjects. Amount of deviation from class I first molar relation, however, were decreased in the contralateral side of observed side. 4. Mandibular height of the ipsilateral side to which mandibular midline shift showed tendency of lower than that of the contralateral side, and there was a tendency that the height was higher in class III subjects, then class II subjects, and lower in class I subjects. However, condylar height did not show any difference in the subjects with midline shift and also show no difference by the first molar occlusal relation.

• 한국해양공학회지
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• 제32권2호
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• pp.123-130
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• 2018

The present study investigated the validity of an equilibrium shoreline empirical formula for real phenomena. Among three types of equilibrium shoreline formulas, Hsu's parabolic type static formula was employed, which is well-known and the most practical for shoreline estimation after coastal or harbor structure construction. The wave data observed at Maengbang beach and the CERC formula on longshore sediment transport were used in the present investigation. A comparison study was only conducted for the case of a shoreline change after the construction of a groyne. Reasonable agreement was seen between the observed wave data and the data obtained under a wave angle spreading function S = 3.5. However, significant changes were observed when S increased. Thus, careful application is required when using Hsu's formula.

• Ocean Systems Engineering
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• 제1권4호
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• pp.297-315
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• 2011

New applications of streamlined Autonomous Underwater Vehicles require an AUV capable of completing missions with both high-speed straight-line runs and slow maneuvers or station keeping tasks. At low, or zero, forward speeds, the AUV's control surfaces become ineffective. To improve an AUV's low speed maneuverability, while maintaining a low drag profile, through-body tunnel thrusters have become a popular addition to modern AUV systems. The effect of forward vehicle motion and sideslip on these types of thrusters is not well understood. In order to characterize these effects and to adapt existing tunnel thruster models to include them, an experimental system was constructed. This system includes a transverse tunnel thruster mounted in a streamlined AUV. A 6-axis load cell mounted internally was used to measure the thrust directly. The AUV was mounted in Memorial University of Newfoundland's tow tank, and several tests were run to characterize the effect of vehicle motion on the transient and steady state thruster performance. Finally, a thruster model was modified to include these effects.

• 한국인쇄학회지
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• 제13권1호
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• pp.73-91
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• 1995

Spectroscopic and Photoelectric Characteristics in the Cyanine and Merocyanine Dye according to systematically change of their structures were experimentally discussed. As result, in solution, Hetero atoms(X) of Cyanine and Merocyanine dye were participated in resonance X of d obital rather than X of pobital,effected in resonance and contributed in extension of conjugated system. in solid film,new spectra,called eximer-fluorenscence,were appeared in 3-dimensional fluorenscence of high density of Cyanine dye but not of Merocyanine. The activational energy of conductivity in Merocyanine dye was lower than in cyanine, an the contrary,the drift mobility was higher and the former in photoelectric characteristics was more effec-tive than the latter. In this paper,authors invertigated the changes of dye structure by molecular obital method to confirm the results of spectroscopic and photoelectric characteristics in the Cyanine and Merocyanine Dye acco-rding to systematically cally change of their structure, and counted total energy on dihedral angle and dipol miments if dyes in S0 and S1.

• 로봇학회논문지
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• 제4권4호
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• pp.289-297
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• 2009

This paper presents the development and control of a two wheeled car-like mobile robot using balancing mechanism whose heading control is done by turning the handle. The mobile inverted pendulum is a combined system of a mobile robot and an inverted pendulum system. A sensor fusion technique of low cost sensors such as a gyro sensor and a tilt sensor to measure the balancing angle of the inverted pendulum robot system accurately is implemented. Experimental studies of the trajectory following control task has been conducted by command of steering wheel while balancing.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1989년도 추계학술대회 논문집 학회본부
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• pp.131-135
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• 1989

Hot electron simulation of silicon using Monte Carlo method was carried out to investigate impact ionization characteristics near the drain of MOSFET's at 77 and 300K. We successfully characterized drift velocity and impact ionization at 77 and 300K employing a simplified energy band structure and phonon scattering mechanisms. Woods' soft energy threshold model was introduced to the Monte Carlo simulation of impact ionization, and good agreement with reported experimental results was resulted by employing threshold energy of 1.7 eV. It is suggested that the choice of the critical angle between specular reflection and diffusive scattering of surface roughness scattering may be important in determining the impact ionization charateristics of Monte Carlo simulation near the drain of MOSFET's.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2009년도 정보 및 제어 심포지움 논문집
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• pp.408-410
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• 2009

We present an efficient and robust measurement model for visual tracking. This approach builds on and extends work on subspace representations of measurement model. Subspace-based tracking algorithms have been introduced to visual tracking literature for a decade and show considerable tracking performance due to its robustness in matching. However the measures used in their measurement models are often restricted to few approaches. We propose a novel measure of object matching using Angle In Feature Space, which aims to improve the discriminability of matching in subspace. Therefore, our tracking algorithm can distinguish target from similar background clutters which often cause erroneous drift by conventional Distance From Feature Space measure. Experiments demonstrate the effectiveness of the proposed tracking algorithm under severe cluttered background.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 1992년도 한국자동제어학술회의논문집(국내학술편); KOEX, Seoul; 19-21 Oct. 1992
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• pp.564-566
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• 1992

It is tragic that the Korean Airline Boing 747, KE007, wandered hundreds of miles off course into Soviet airspace and was shot down on September 1, 1983. The exact cuases are not known yet. Thus, speculation centers on human error or faulty procedure of three Litton LTN-72R inertial navigation systems(INS) with which the KAL KE007 was equipped. The inertial platform must be aligned before the INS can be used as a precision inertial navigation system. This analysis checks a possibility that the navigation errors are caused by a wrong INS alignment procedure assuming it is done at Anchorage. Possible causes for the navigational position error, such as alignment errors and gyro drift errors, are analyzed through inertial navigation system error prapagation simulations. A set of misalignment angle is estimated to determine what degree of alignment errors are required to cause the navigation error assuming that the accident is caused by the INS misalignment.

• 제어로봇시스템학회논문지
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• 제14권9호
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• pp.881-885
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• 2008

To calculate the attitude in ARS(Attitude Reference System) using 3 gyros and 3 accelerometers, gyro drift must be compensated with accelerometer to avoid divergence of attitude error. Kalman filter is most popular method to integrate those two sensor outputs. In this paper, new Kalman filtering method is proposed for roll and pitch attitude estimation. New states are defined to make linear equation and algorithm for changing Kalman filter parameters is proposed to ignore disturbances of acceleration. This algorithm can be easily applied to low cost ARS.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 2000년도 제15차 학술회의논문집
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• pp.91-91
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• 2000

In this paper, the error compensation method of the attitude reference system with low-cost IMU is proposed. In general, the attitude error calculated by gyro grows with time. Therefore the additional information is required to compensate the drift. The attitude angles can be bound by accelerometer mixing algorithm and the heading angle can be aided by GPS velocity information. The Kalman filter is used for error compensation. The result is verified by comparing with the attitude calculated by medium-grade IMU, LP-81.