• Proceedings of the Korea Committee for Ocean Resources and Engineering Conference
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• 2006.11a
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• pp.351-354
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• 2006

In underwater environment, the control of AUV is difficult, because of the existence of parameter uncertainties and disturbances as well as highly nonlinear and coupled system dynamics. The requirement for the simple and robust controller which works satisfactorily in those dynamical uncertainties, call for a design using the PD or sliding mode controller. The PD controller is very popular controller in the industrial field and the sliding mode controller has been used successfully for the AUV controller design. In this paper, the two controllers arc designed for ISiMI(Integrated Submergible Intelligent Mission Implementation) AUV and the performances are compared by numerical simulation under the modeling uncertainty and disturbances. The design process of PD and sliding mode controller for ISiMI AUV and simulation results are included to compare the performances of the two controllers.

• Journal of the Korean Society of Propulsion Engineers
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• v.4 no.4
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• pp.107-113
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• 2000

Design configuration and performance requirements for KOMPSAT-1 propulsion system were described. Operational results of the propulsion system obtained through the satellite Launch and Early Operation Phase were scrutinized. Performance characteristics of the thrusters which are employed for spacecraft attitude control and the corresponding propellant depletion rate were analysed according to satellite operation modes. Additionally, propellant leakproof and thermal control capability were checked out from the view point of system verification. Propellant depletion rates calculated by PVT method in $\Delta$V maneuvering and each attitude control mode produce the very meaningful results for the prediction of total propellant consumption up to the end of satellite mission life.

• Journal of the Semiconductor & Display Technology
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• v.21 no.4
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• pp.121-125
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• 2022

This paper deals with the development of a deep-learning-based robot that recognizes various types of stairs and performs a mission to go up to the target floor. The overall motion sequence of the robot is performed based on the ROS robot operating system, and it is possible to detect the shape of the stairs required to implement the motion sequence through rapid object recognition through YOLOv4 and Cuda acceleration calculations. Using the ROS operating system installed in Jetson Nano, a system was built to support communication between Arduino DUE and OpenCM 9.04 with heterogeneous hardware and to control the movement of the robot by aligning the received sensors and data. In addition, the web server for robot control was manufactured as ROS web server, and flow chart and basic ROS communication were designed to enable control through computer and smartphone through message passing.

• The Transactions of the Korean Institute of Electrical Engineers D
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• v.51 no.5
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• pp.175-181
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• 2002

In this paper, fault tolerant digital governor is designed to realize ceaseless controlling and to improve the reliability of control system. Designed digital governor huts duplex I/O module and triplex CPU module and also 2 out of 3 voting algorithm and self diagnostic ability. The Processor module of the system(SIDG-3000) is developed based on 32 Bit industrial microprocessor, which guaranteed high quality of the module and SRAM for data also SRAM for command are separated. The process module also includes inter process communication function and power back up function (SRAM for back-up). System reliability is estimated by using the model of Markov process. It is shown that the reliability of triplex system in mission time can be dramatically improved compared with a single control system Designed digital governor system is applied after modelling of the steam turbine generator system of Buk-Cheju Thermal Power Plant. Simulation is carried out to prove the effectiveness of the designed digital governor system

• Journal of Institute of Control, Robotics and Systems
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• v.19 no.5
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• pp.442-449
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• 2013

In this paper, a simulation system based on X-Plane and MATLAB/Simulink for multiple UAVs is presented. For the conceptual design of this proposed system, a hierarchical system architecture for multiple UAVs is presented. This architecture has object-oriented data structure which consists of three objects (UAV status, mission and task, and environment) and a hierarchy consisting of four layers (decision making layer, task assignment layer, path and motion planning layer, and collision avoidance layer) is also proposed. In addition, this paper shows a implementation of simulation system based on the proposed system architecture using X-Plane and MATLAB/Simulink. The result of simulation from the developed system in this paper validate capability of application for multiple UAVs in real environment.

• Proceedings of the KSRS Conference
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• v.1
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• pp.67-70
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• 2006

KARI is developing Image Data Acquisition and Control System (IDACS) for pre-processing meteorological and ocean data acquired on geostationary orbit. This paper describes the functions and architecture of IDACS and gives its operation policy including backup operation to overcome limitation of single-configured antenna system. The COMS IDACS provides the capability to receive the raw sensor data and disseminate processed MI data to users via a satellite. From the processed image data, users can produce a set of meteorological and ocean products for a wide range of applications. Most of IDACS subsystems are being developed by Korean technologies and experience acquired from previous projects. In case of COMS geometric correction software module, as it is closely dependent on the characteristics of imagers and spacecraft bus system, it is being co-developed with overseas prime contractor who develops spacecraft bus system.

• 제어로봇시스템학회:학술대회논문집
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• 2005.06a
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• pp.241-245
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• 2005

Strapdown inertial navigation system (SINS) integrated with astronavigation system (ANS) yields reliable mission capability and enhanced navigational accuracy for spacecrafts. The theory and characteristics of integrated system based on unscented Kalman filtering is investigated in this paper. This Kalman filter structure uses unscented transform to approximate the result of applying a specified nonlinear transformation to a given mean and covariance estimate. The filter implementation subsumed here is in a direct feedback mode. Axes misalignment angles of the SINS are observation to the filter. A simple approach for simulation of axes misalignment using stars observation is presented. The SINS error model required for the filtering algorithm is derived in space-stabilized mechanization. Simulation results of the integrated navigation system using a medium accuracy SINS demonstrates the validity of this method on improving the navigation system accuracy with the estimation and compensation for gyros drift, and the position and velocity errors that occur due to the axes misalignments.

• Asian Pacific Journal of Cancer Prevention
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• v.13 no.12
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• pp.5969-5973
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• 2012

Introduction: Andhra Pradesh (AP) is one of the largest tobacco producing states in India. About 29% of adults in AP currently use tobacco in some form. Almost 24% of males and 4% of females are smokers. The prevalence of tobacco use in the state is higher than the national average of 15% for male and 2% for female smokers. However, few attempts have been made to understand the current situation of tobacco control resources, activities and strategies in the context of such a high tobacco prevalence state. The present study aimed to identify the gaps in existing tobacco control program and areas where tobacco control efforts can be integrated. Methods: Data were collected using both quantitative and qualitative methods. Semi-structured interviews were undertaken with a total of 95 key officials of state health departments, program managers, and project directors in six districts to understand ongoing tobacco control efforts. To facilitate the interviews, semi-structured guides were developed. Simple descriptive statistical analysis was conducted on the quantitative data using SPSS version 17. Results: The results of the situational analysis suggest that a sufficient health workforce and infrastructure with the potential to integrate tobacco control activities is available in the surveyed districts. However, lack of integration of the tobacco control program intothe tuberculosis control program and the National Rural Health Mission was observed. Information, education and communication activities were lacking at block level health facilities. Conclusions: Our findings indicate that lack of trained health professionals, paucity of dedicated funds, lack of information, education and communication materials and low priority given to tobacco control activities are some of the factors which impede integration of tobacco control into existing health and developmental programmes in the districts of Andhra Pradesh, India.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.30 no.3
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• pp.46-56
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• 2002

In this paper, the feasibility of the attitude control of a spacecraft using pulsed plasma thrusters(PPTs) is studied. The PPT consumes less propellant mass requied for the orbit management or attitude control owing to its high specific impulse characteristics, compared with traditional gas propulsion system. The PPT is expected to be highly adequete for the missions requiring long-duration operations because it has relatively long operation time and easy implementation. The feasibility of the PPT for attitude control of a small satellite system is addressed through realistic missions. The classical PD controller and a fuzzy logic controller are tested, and fuel saving fuzzy logic controller is then proposed for more flexible mission performance.

• Journal of Satellite, Information and Communications
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• v.1 no.2
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• pp.71-75
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• 2006

This paper describes operation plans for satellite communications system (SATCOM) which is consisted of Ka band communication payload, geostationary satellite control system and communication test earth station system for the communication, ocean and meteorological satellite system (COMS). Also this paper describes the communication service and mission plans by each system of the SATCOM, and configurations and functions of the system interface between each system. Especially this paper proposes operational items, functions and their configuration diagrams, touches their operational plans. This paper describes function definitions, configuration diagram and operation plans of the PCS )Payload Control System) for monitor and control of the communication payload and communication service network of the SATCOM.