• Journal of the Korean Society for Precision Engineering
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• v.19 no.2
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• pp.140-150
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• 2002

The planar tracked vehicle model used in this investigation consists of two kinematically decoupled subsystems, i.e., the chassis subsystem and the track subsystem. The chassis subsystem includes the chassis frame, sprocket, idler and rollers, while the track subsystem is represented as a closed kinematic chain consisting of rigid links interconnected by revolute joints. In this study, the recursive kinematic and dynamic formulation of the tracked vehicle is used to find the vertical terce and the distance of an arbitrary track moved in the driving direction along the track. These distances and vertical forces obtained are used to get the deformation and sinkage of a terrain. The FEM(Finite Element Method) is adopted to analyze the interaction between tracked vehicle and terrain. The terrain is represented by a system of elements wish specified constitutive relationships and considered as a piecewise linear elastic, plastic and isotropic material. When the tracked vehicle is moving with different speeds on the terrain, the elastic and plastic deformations and the maximum sinkage for the four different types of isotropic soils are simulated.

• Proceedings of the Korea Contents Association Conference
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• 2007.11a
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• pp.178-182
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• 2007

In this paper, we design and implement the UCC services prototype system for image and video. The proposed system consists of the two components such as the multimedia processing subsystem and the metadata management subsystem, and provides the API to UCC service developers. The multimedia processing subsystem supports the media management and editing of image and video, and the streaming services of video. The metadata management subsystem supports the metadata management and retrieval of image and video, and the reply management and script processing of UCC.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.35 no.9
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• pp.850-857
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• 2007

The design and analysis of satellite electrical power subsystem is an important driver for the mass, size, and capability of the satellite. In particular, satellite energy balance analysis is critical in determining the capabilities and limitations of the power subsystem and the success of satellite operations. This paper introduces a new energy balance analysis program for LEO satellite development and shows an example of test results using other LEO satellite design data. The test results show that the proposed energy balance program can be used the optimal sizing of satellite electrical power subsystem and the analytical prediction of the on-orbit energy balance during satellite mission operations.

• Journal of Nutrition and Health
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• v.20 no.1
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• pp.54-64
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• 1987

The purpose of this study is to computerize all the necessary information on the daily food value and nutritional status for individuals and groups. In this research, a FOCUS-16jXT (16 bit personal computer ) compatible with IBM-PCjXT was used, and the database files and programs were created by using the dBASEIII package. The food life evaluation system consists of 3 subsystems of Reference, Nutrition Status Assessment and Food Source. The findings are summerized a8 follows: 1. Reference: This subsystem enables users to proceed to the next step, if necessary, by describing each subsystem. 2. Nutrition Status Assessment. 1) Food Habit Assessment: This subsystem determines whether the user has a good food habit or not, based on the answers for ten questions about daily food life. 2) Obesity Assessment: This subsystem calculates Broca index, which is used as a indicator of obesity. 3) Nutrient Intakes: When personal data such as age, sex, weight, height and food consumptions are input, it is possible to calculate the followings. i) Comparison between the amounts intaked and the recommended dietary daily allowances of various nutrients ii) Nutrient intakes from each food group and their composition rates for the nutrients iii) Nutrient intakes per unit body surface area iv) Composition of lipid intake 3. Food Sources: The appropriate food sources for the lacking nutrients will be recommended to the subjects.

• The Transactions of the Korean Institute of Electrical Engineers D
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• v.49 no.8
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• pp.459-466
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• 2000

In this paper, we propose an attitude controller for an unstructured object using CMG(Control Moment of Gyro) subsystem, which has a stabilizer function. The CMG subsystem consists of one motor for spinning the wheel and the other motor for turning the outer gimbal. While the wheel of CMG subsystem is spinning at high speed, applying force to the spin axis of the wheel leads the torque about the vertical axis. We utilize the torque to control the attitude of object in this study. For the stabilizer function, in additiion, holding the load at the current position, the power applied to the gimbal motor of CMG will be cut, which result in the braking force to stop the load by gyro effect. However, due to the gear reduction connected to outer gimbal, slow load motion cannot generate the braking force. Thus, in this study, we are willing to make a holding force by applying control power to the gimbal motor from the signal of piezoelectric gyroscopic sensor that detected the angular velocity of the load. These two features are demonstrated in experiment, carrying a beam with crane. As a result, load was started to rotate by controlling gimbal positiion and was stopped by turning off the gimbal power. Moreover, slow movement of the load was also rejected by additional control with gyroscopic sensor.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 1994.10a
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• pp.670-675
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• 1994

Yhis paper describes a fault diagnosis simulation of the Real-Time Multiple Fault Dignosis System (RTMFDS) for forcasting faults in a system and deciding current machine state from signal information. Comparing with other diagnosis system for single fault,the system developed deals with multiple fault diagnosis,comprising two main parts. One is a remotesignal generating and transimission terminal and the other is a host system for fault diagnosis. Signal generator generate the random fault signal and the image information, and send this information to host. Host consists of various modules and agents such as Signal Processing Module(SPM) for sinal preprocessing, Performence Monotoring Module(PMM) for subsystem performance monitoring, Trigger Module(TM) for multi-triggering subsystem fault diagnosis, Subsystem Fault Diagnosis Agent(SFDA) for receiving trigger signal, formulating subsystem fault D\ulcornerB and initiating diagnosis, Fault Diagnosis Module(FDM) for simulating component fault with Hierarchical Artificial Neural Network (HANN), numerical models and Hofield network,Result Agent(RA) for receiving simulation result and sending to Treatment solver and Graphic Agent(GA). Each agent represents a separate process in UNIX operating system, information exchange and cooperation between agents was doen by IPC(Inter Process Communication : message queue, semaphore, signal, pipe). Numerical models are used to deseribe structure, function and behavior of total system, subsystems and their components. Hierarchical data structure for diagnosing the fault system is implemented by HANN. Signal generation and transmittion was performed on PC. As a host, SUN workstation with X-Windows(Motif)is used for graphic representation.

• Transactions of the Korean Society of Automotive Engineers
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• v.17 no.1
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• pp.162-168
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• 2009

The real-time multibody vehicle model based on the subsystem synthesis method has been developed. Suspension, anti roll bar, steering, and tire subsystem models have been developed for vehicle dynamics. The compliance effect from bush element has been considered using a quasi-static method to achieve the real time requirement. To validate the developed vehicle model, a quarter car and a full vehicle simulations have been carried out comparing simulation results with those from the ADAMS vehicle model. Real time capability has been also validated by measuring CPU time of the simulation results.

• Journal of Satellite, Information and Communications
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• v.2 no.1
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• pp.48-55
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• 2007

The system requirement definition, system configuration, major parameters for GNSS ground station development are presented in this paper. GNSS ground station system consists of the GNSS sensor station, up link station and monitoring & control system. The GNSS sensor station consists of navigation receiver subsystem which process the GPS and Galileo navigation signal, automic clock subsystem, meteorological data receiving subsystem and navigation data processing subsystem. To communicate the error correction of navigation fate, GNSS sensor station interface with GNSS Control Center.

• International Journal of Control, Automation, and Systems
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• v.3 no.1
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• pp.70-78
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• 2005

This paper presents hybrid control of displacement and force in a Medical Tele-Analyzer by disturbance observer-based controller which is robust to internal and external disturbances; model uncertainty, load, and friction for instances. The developed Medical Tele-Analyzer consists of 2 subsystems; doctor-side subsystem and patient-side subsystem. In the doctor side subsystem, an array of displacement sensor is equipped to detect movement of doctor's hand and fingers. The detected information is transmitted to the patient side to be used in medical analysis. On the other hand, the patient-side subsystem consists of an array of displacement actuators, which is used to follow displacement of doctor's hand and fingers. An array of force sensors is used to detect forces between patient and the equipment. Since displacement control in patient side is coupled with force control in doctor side and vice-versa, design of the controller has to take into account this coupling. Not only using in medical tele-analysis, the proposed system can also be used in any tele-displacement-force controls of industrial processes.

• Journal of Power Electronics
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• v.6 no.1
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• pp.18-28
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• 2006

The Electric Power Subsystem (EPS) is one of the most critical systems on any satellite because nearly every subsystem requires power. This makes the choice of power systems the most important task facing satellite designers. The main purpose of the Satellite EPS is to provide continuous, regulated and conditioned power to all the satellite subsystems. It has to withstand radiation, thermal cycling and vacuums in hostile space environments, as well as subsystem degradation over time. The EPS power characteristics are determined by both the parameters of the system itself and by the satellite orbit. After satellite separation from the launch vehicle (LV) to its orbit, in almost all situations, the satellite subsystems (attitude determination and control, communication and onboard computer and data handling (OBC&DH)), take their needed power from a storage battery (SB) and solar arrays (SA) besides the consumed power in the EPS management device. At this point (separation point, detumbling mode), the satellite's angular motion is high and the orientation of the solar arrays, with respect to the Sun, will change in a non-uniform way, so the amount of power generated by the solar arrays will be affected. The objective of this research is to select satellite EPS component types, to estimate solar array illumination parameters and to determine the efficiency of solar arrays during both detumbling and normal operation modes.