• Journal of information and communication convergence engineering
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• v.5 no.2
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• pp.83-87
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• 2007

This research studies real time interaction and dynamic data shared through 3D scenes in virtual network environments. In a distributed virtual environment of client-server structure, consistency is maintained by the static information exchange; as jerks occur by packet delay when updating messages of dynamic data exchanges are broadcasted disorderly, the network bottleneck is reduced by predicting the movement path by using the Dead-reckoning algorithm. In Dead-reckoning path prediction, the error between the estimated and the actual static values which is over the threshold based on the shared object location requires interpolation and multicasting of the previous location by the ESPDU of DIS. The shared dynamic data of the 3D virtual environment is implementation using the VRML.

• 제어로봇시스템학회:학술대회논문집
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• 1997.10a
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• pp.1403-1406
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• 1997

Generally, G.P.S(Global Positioning System) is using for the car navigation system but it has some restrictions such as the discontinuity of earth satellites and SA (Selective Availability). Recently, the hybrid navigation system combining with G.P.S and Dead-reckoning are much attractuve for improving the accuracy of a vehicle positioning. G.P.S called satellite navigation system, can measure its position by using satellites. Dead-Reckoning is the self-contained navigatioin system using a wheel sensor for the vehicle velocity and a gyro sensor for the vehicle angular velocity. Some algorithm could be generated for finding the vehicle position and orientation. In this paper, we developed a hybrid algotithm wiht G.P.S DR and Map-Matching.

• Proceedings of the KIPE Conference
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• 2013.11a
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• pp.41-43
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• 2013

PMSM 구동을 하였을 때, 인버터의 지령전압과 출력전압 사이에 왜곡이 발생하며, 대부분 Dead Time에 의한 영향 이다. 전압왜곡을 보상하는 여러 가지 방법 들이 연구되어왔다. 하지만 전압 왜곡의 보상이 abc 축 또는 dq축에서 이루어지고 있으나 어느 방식이 더 좋은지에 대한 검토가 없었다. 본 논문에서는 d-q축 전압방정식과 abc축 전압방정식으로부터 왜곡된 전압을 보상하는 방법을 비교한다.

• Korean Journal of Optics and Photonics
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• v.8 no.4
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• pp.353-355
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• 1997

A single molecule detection system, which consists of confocal fluorescence microscope and single photon counter, has been used to observe the dye concentration dependence of photon counting rate. With increasing concentration, a saturation effect of counting is observed and demonstrated on the basis of the dead time of photon detector. The equations presented here show the relations between the counting rate and some parameters such as probe volume, quantum efficiency of detector, and fluorescence photon number entered onto detector. The signal-to-noise ratio is also discussed briefly.

• Journal of Advanced Marine Engineering and Technology
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• v.24 no.1
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• pp.119-126
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• 2000

In constructing the positioning system based on a conventional dead-reckoning for a wheeled vehicle with pneumatic tires, the position estimation error is inevitable as changes of the radius of the wheels depend on live load and variable enviroment. Therefore, this paper proposes the positioning system which can estimate the error source i.e. the vehicle parameter errors, such as the right and left wheel radius error, using gyroscope and ultrasonic sensor and correct the parameter to reduce the dead-reckoned position estimation error. The extended Kalman filter was used as a method for the multisensor data fusion. The simulation to verify the effectiveness of the proposed positioning system is performed.

• Journal of the Korean Society of Manufacturing Technology Engineers
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• v.9 no.2
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• pp.119-124
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• 2000

In this paper based on geometric optics and geometric modeling aspheric surface of the side mirror mold with dead angle reduced have been designed and machined in a CNC machining center, Surface roughness of the mold was evaluat-ed by usin the surface shaping system. Surface generating simulation of a ball endmill process is investigated. Through the simulation based on the surface-shaping system 3-D engineered surfaces and properties of engineered surfaces are obtained, Computer simulation provides the effective working conditions through the prediction of geometric properties of engineered surfaces. The rear view mirror and room mirror play important role on the safe driving condition as a observation of environment but the rear view mirror can not provide complete information of driving environments due to the existence of the dead angle. The analysis on the shape of formed mirror shows that the proposed me？ improves range of a driver's sight.

• Transactions of the Korean Society of Automotive Engineers
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• v.21 no.4
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• pp.188-194
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• 2013

Hydrostatic pumps and motors occupy an important position in hydraulic system. There are a lot of researches on characteristics of hydraulic pumps, but not hydraulic motors. So in order to know the characteristics of hydraulic motors we had this research. The purpose of this study is to derive and analyze the theoretical calculation of hydraulic axial piston motor torque and torque ripples. Then, analyzed the differences between torque ripples with dead place and without dead place on the valve plate, and modeling a hydraulic motor with AMESim software. Finally, theoretical calculation of hydraulic motor torque ripples was verified from the viewpoint of simulation.

• Proceedings of the Korean Society of Agricultural Engineers Conference
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• 1998.10a
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• pp.473-478
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• 1998

Dead animals amended with agricultural rersidues are utilized ai a compost to promote soil fertility and reduce environmental pollution by traditional methods of livestock mortalities. The full-scale bin composting swine mortality in roofed system with three amendments was very successful in reaching sufficient temperature above 55$^{\circ}C$ long enough for pathogen kill. The average temperature of tile compost material in dead swine amended with corn stover increased rapidly to 64$^{\circ}C$ on the 2nd day after primary composting and dropped to near ambient temperature on the 140th day of composting. The composting temperature of corn stover and wheat straw is more efficient for swine carcass composting than that of sawdust.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• 2014.06a
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• pp.287-289
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• 2014

선박의 선위 추측(DR, Dead Reckoning)은 수신되거나 측정된 위치 데이터와 속력, 침로 데이터만을 반영하여 계산하므로 대양의 항해나 연근해의 해역에서는 유효할 수 있으나 침로의 변경과 선속의 변화가 잦은 항계 내의 조선에 있어서는 적용이 어렵다는 문제점이 있다. 본 논문에서 제안하는 선박의 추측위치(DRP, Dead Reckoning Position)는 선박의 운항 패턴에 따라 항계 내의 항적 데이터를 수집하고, 수신된 위치 데이터와 속력, 침로 데이터를 점장위도항법(Mercator Sailing)을 통하여 계획항로(Planned Route)의 각 변침점(WP, Waypoint)간 침로(Course)와 항정(Ship's Passage)에 반영하였다. 제안된 추측위치 산출방법을 통하여 항계 내의 조선과정에서 계획항로를 선박의 추측위치와 결합하여 특정 시간 후의 상황패턴을 미리 예측하고 관제사의 의사결정에 기여하고자 한다.

• Journal of Electrical Engineering and Technology
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• v.4 no.4
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• pp.443-450
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• 2009

This paper deals with the design of decentralized controller for load-frequency control of interconnected power systems with superconducting magnetic energy storage units and Governor Dead Band Nonlinearity using Multi-Objective Evolutionary Algorithm. The superconducting magnetic energy storage unit exhibits favourable damping effects by suppressing the frequency oscillations as well as stabilizing the inter-area oscillations effectively. The proposed control strategy is mainly based on a compromise between Integral Squared Error and Maximum Stability Margin criteria. Analysis on a two-area interconnected thermal power system reveals that the proposed controller improves the dynamic performance of the system and guarantees good closed-loop stability even in the presence of nonlinearities and with parameter changes.