• KIPS Transactions on Computer and Communication Systems
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• v.8 no.12
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• pp.277-286
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• 2019

The Unmanned Aerial Vehicle (UAV) is one of the most precious inventions of Internet of things (IOT). UAV faces the necessity to charge battery or replace battery from the charging stations during or between services. We propose scheduling algorithms for drone power charging (SADPC). The basic idea of algorithm is considering both a deadline (for increasing deadline miss ratio) and a charging time (for decreasing waiting time) to decide priority on charging station among drones. Our simulation results show that our power charging algorithm for drones are efficient in terms of the deadline miss ratio as well as the waiting time in general in compare to other conventional algorithms (EDF or SJF). Also, we can choose proper algorithms for battery charge scheduling and charge ready battery allocation according to system parameters and user requirements based on our simulation.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.39 no.2
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• pp.121-127
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• 2011

This paper presents an autonomous formation flight algorithm for micro aerial vehicles (MAVs) and its flight test results. Since MAVs have severe limits on the payload and flight time, formation of MAVs can help alleviate the mission load of each MAV by sharing the tasks or coverage areas. The proposed formation guidance law is designed using nonlinear dynamic inversion method based on 'Leader-Follower' formation geometric relationship. The sensing of other vehicles in a formation is achieved by sharing the vehicles' states using a high-speed radio data link. the designed formation law was simulated with flight data of MAV to verify its robustness against sensor noises. A series of test flights were performed to validate the proposed formation guidance law. The test result shows that the proposed formation flight algorithm with inter-communication is feasible and yields satisfactory results.

• Journal of Satellite, Information and Communications
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• v.7 no.1
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• pp.86-91
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• 2012

This paper described validation results of COMS Ka band antennas beam coverages which were developed by ETRI. After satellite launch, In Orbit Test(IOT) activities are stat to check spacecraft and payloads are still in healthy condition after launch. During IOT phase, ETRI measured radiation patterns of COMS Ka band antennas and compare with ground test(CATR) results. The antenna patterns similarity between IOT results and CATR results show that COMS Ka band antenna withstand launch vibration and in the good healthy condition. After IOT, ETRI performed field test for beam coverage measurements with vehicle to check if Ka band beam coverage are formed well as designed. For the beam coverage measurement, 17 points were selected over the Korean peninsula. The field measurement data were very similar with CATR data and this confirms that beam coverage are formed well over the Korean peninsula as expected.

• Korean Institute of Interior Design Journal
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• v.21 no.5
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• pp.328-335
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• 2012

Due to development of digital technology, a concept of stage design management is being changed. In addition, stage management technique is changing a viewpoint of the audience watching a stage through the convergence of analogue and digital technology. Three-dimensional media such as LED and hologram and works combining with previous stage performances are rising, and the audience's requirements about spectacles on the stage are increasingly higher. Interaction between a stage, audiences and actors is a communication tool by a work story and its direction. In other words, stage design should newly focus on not only concluded work story but also comprehensive delivery of direction and the expression and extreme delivery. Therefore, this study aims to examine how to combine analogue and digital direction elements in the stage design. To this end, this study looks into everything the audience feels through performances and analogue and digital elements directed for performances and then analyzes and arranges them to present a possibility of various types of work performances. Stage structure, set, and lighting that are analogue direction elements are the basis of stage performance. Analogue direction elements mean a media vehicle that can differentiate except for basic direction of each work. This study aims to analyze new performance culture when analog and digital direction elements are combined through stage performance and a possibility of new stage performance. In addition, through this it desired to seek for a development possibility of Korean leisure culture and art culture. As the work cases, this study shows 10 works through actual stage performances held in Korea and introduces elements directed in those works.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.10 no.6
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• pp.1147-1152
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• 2006

This paper proposed modelling and design method in suspension system design to analyze sky hook damper system by adopting active robust control theory. Recent in the field of suspension system design it is general to adopt active control scheme for stiffness and damping, and connection with other vehicle stability control equipment is also intricate, it is required for control system scheme to design more robust, higher response and precision control equipment. It is known that sky hook suspension system is better than passive spring-damper system in designing suspension equipment. We analyze location of sensor and actuator in sky hook system and its motion equation, then design robust control system. Numerical example is shown for validity of robust control system design in active sky hook suspension system.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.19 no.1
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• pp.244-250
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• 2015

Survivability is avoidance and tolerance ability of combat systems for accomplishing mission in battle field. Therefore, the combat system has to protect or minimize any damage from threats. For this reason, many modeling and simulation based studies which analyze vulnerability of the combat system by threats, are in progress to improve survivability of the combat system. In this paper, we developed a 3D penetration analysis program for survivability analysis of combat system. To do this, we applied the penetration analysis equation to threat and protection performance of tank. Also we implemented simple tank models based on 3D CAD, and tested the developed program using the implemented tank models. As a result, we verified the developed program that is possible to analyze penetration by threat and protection performance of tank and to visualize its result, based on scenarios.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.13 no.7
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• pp.1437-1443
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• 2009

This paper is presented an simultaneous localization and mapping (SLAM) algorithm using ultrasonic for robot and electric compass, encoder, and gyro. Generally, localization based upon electric compass, encoder, and gyro can be measured just local position in workspace. However, actual robot must need an information of the absolute position in workspace to perform its mission, Absolute position in workspace could be calculated using SLAM algorithm. To implement SLAM in this paper, a map is built using ultrasonic sensor and hierarchical map building method. And then, we the map will be transformed into a feature map. The absolute position could be calculated using the feature map and map mapping method. As a test bed, we designed and construct an autonomous robot and showed the experimental performance of the proposed SLAM algorithm based on feature map. Experimental result, we verified that robot can found all absolute position on experiments using proposed SLAM algorithm.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.17 no.12
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• pp.2899-2905
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• 2013

According to developing wireless communications in vehicle, various security threat in the WAVE(Wireless access in vehicular environments) is increased. To protect this, IEEE 1609.2 specify services as for prevent message from attacks such as spoofing, eavesdropping and replay. It is possible to implement a hardware library for defending these attacks. In this paper, we proposed a efficient AES-CCM architecture for the hardware library in the WAVE. We compare our architecture to the previous one in the same FPGA. And our design uses less slices than 27 % of it and less slices than 45 % of it if we share registers that were used by other modules in the library. We also achieves a throughput of 1355 Gbits/s in xc5vlx110t-2ff1136.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.17 no.12
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• pp.2995-3000
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• 2013

We investigated the effects of testosterone on the improvement of white adipose tissue explant and its molecular mechanism in adipose tissue of high fat diet-fed male castrated (CAST) mice. The CAST mice treated with testosterone had lower adipose tissue weights, the average size of adipocytes and mRNA levels of $C/EBP{\alpha}$ as well as adipocyte marker genes than the vehicle-treated CAST mice. These results suggest that testosterone prevent the expression of $C/EBP{\alpha}$ and $C/EBP{\alpha}$-mediated adipocyte marker genes, resulting in decreased adipose tissue mass and adipocyte metabolism in male CAST mice. Moreover, this study give a valuable molecular and biological knowledge on testosterone therapy in obese hypogonadal men.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.17 no.12
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• pp.2853-2858
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• 2013

This paper proposes the ITMS(Intelligent Transport Monitoring System) which manages the route and state of freight by using the Meteorological Office, the Transportation Management Center, GPS and Sensors, etc. The ITMS consists of the CIMS(Container Inner Monitoring System) transmitting the inner temperature and humidity of a container, the TMM(Transport Management Module) computing an estimated time of arrival with Freight Vehicle location information and transmits the result to the CIMS, the FMM(Freight Management Module) checking and managing the freight freshness by using the temperature and humidity of the collected containers, and the SMM(Stevedoring Management Module) selecting the container loading and unloading places with the information transmitted from the CIMS, the TMM, and the FMM and attaching the freight formation to containers using an RFID label. The ITMS not only checks the freight condition at intervals but also acquires and manages the freight information with RFID labels rapidly and accurately.