Certification Criteria, Patent Analysis and Aerodynamic Analysis for a Roadable PAV Design
차재영 Jae-young Cha , 황호연 Ho-yon Hwang , 정한규 Han-gyu Jeong , 김석범 Seok-beom Kim , 안존 Jon Ahn
21(1) 1-12, 2017
차재영 Jae-young Cha , 황호연 Ho-yon Hwang , 정한규 Han-gyu Jeong , 김석범 Seok-beom Kim , 안존 Jon Ahn
DOI: JANT Vol.21(No.1) 1-12, 2017
As the current ground transportation system becomes saturated, there is a need to develop a roadable personal air vehicle (PAV). Therefore, researches for PAV development and operation system development are being actively carried out in various countries around the world. PAV, the next generation transportation system, is a new concept of personal transportation that combines ground transportation, air traffic, and IT industry. Also, the development of PAV can solve the saturation of traffic congestion and shorten the travel time dramatically. In this study, we analyzed the certification criteria of FAR Part 23, which is going to be revised, and analyzed the patents and folding mechanism of Terrafugia Transition and Aeromobil 3.0, which are the most advanced of roadable PAV. Also, we used OpenVSP® for the reverse configuration design of the existing Terafugia transition and Aeromobile 3.0. Aerodynamic analyses were performed for the reverse configuration design using the XFLR5® program.
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A Warning Threshold Proposal for Operation Improvement of Maritime DGPS Reference Station
최용권 Yong Kwon Choi , 이주현 Ju Hyun Lee , 손석보 Seok Bo Son , 이상정 Sang Jeong Lee
21(1) 12-20, 2017
최용권 Yong Kwon Choi , 이주현 Ju Hyun Lee , 손석보 Seok Bo Son , 이상정 Sang Jeong Lee
DOI: JANT Vol.21(No.1) 12-20, 2017
A maritime DGPS in Korea offers pseudo-range correction information and monitors integrity of correction data by using multiple GNSS receivers. The maritime DGPS reference station and integrity monitor service sets alarm threshold value about integrity monitoring parameters for preventing service interruption status. However there is no way to avoid system interruption according to malfunction of backup systems and outside factors. Therefore, in this paper, warning threshold values were proposed for maritime DGPS operator can be counteract in advance. And Markov analysis method was carried out for selection of these warning threshold values.
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A Design Control System of Hybrid Underwater Glider and Performance Test
지대형 Dae-hyeong Ji , 최형식 Hyeung-sik Choi , 김준영 Joon-young Kim , 정동욱 Dong-wook Jung , 정성훈 Seong-hoon Jeong
21(1) 21-29, 2017
지대형 Dae-hyeong Ji , 최형식 Hyeung-sik Choi , 김준영 Joon-young Kim , 정동욱 Dong-wook Jung , 정성훈 Seong-hoon Jeong
DOI: JANT Vol.21(No.1) 21-29, 2017
In this paper, we studied the control of the hybrid underwater glider (HUG), which has the advantage of high precision route search function and long-term mission capability. Dynamic modeling of HUG is based on numerical model of the attitude controller and buoyancy engine, thruster. We designed the control part considering the smooth control and precise sailing of HUG. A buoyancy engine capable of inhaling water is designed to control the buoyancy of HUG. And mass shifter carrying the battery was designed for controlling pitching motion of HUG. A control system for controlling the buoyancy engine and the attitude controller was constructed. In order to verify performance, we performed water tank test using manufactured HUG.
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Development of Analysis Program for Geographical Separation of Radio Navigation Aids
최재명 Jae-myeong Choi
21(1) 30-35, 2017
최재명 Jae-myeong Choi
DOI: JANT Vol.21(No.1) 30-35, 2017
Radio navigation aids are very important elements to provide information necessary for safe navigation using radio waves. Recently, the number of radio equipment using radio waves is increasing, and the air frequency interference by adjacent channels is very high. In addition, the use of irregular jamming that threatening radio navigation aids and satellite navigation system frequency is rapidly increasing. Therefore, it is urgent to ensure the safety of air waves. In this paper, we investigated the characteristics and frequency of the domestic navigation system. And we were analyzed the geographical separation standard for implementation of analysis program. Also, we implemented a program for the geographical separation distance analysis that applying international standards and recommended practices.
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First-Come First-Served Airport Surface Movement Scheduling.
강선영 Seon-young Kang , 박배선 Bae-seon Park , 이학태 Hak-tae Lee
21(1) 36-42, 2017
강선영 Seon-young Kang , 박배선 Bae-seon Park , 이학태 Hak-tae Lee
DOI: JANT Vol.21(No.1) 36-42, 2017
An airport surface movement scheduler using first-come first-served (FCFS) algorithm is developed to efficiently manage surface traffic in an airport. It is based on the previously developed traffic flow management scheduler. Link directionality and intersection processing, which are additional constraints for ground movement, are added to the scheduler. To verify each of additional constraints, several simulations were performed by making simple scenarios, and the results show that all constraints were satisfied. Also, a simulation was performed by making a scenario based on flight operation information system (FOIS) data which is real departure and arrival flight data of Jeju airport. To determine the practicality of the developed scheduler, we compare the actual average delay time with the average delay time calculated by the scheduler.
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Position and Measurement Performance Analysis of GPS Receiver applied LQG based Vector Tracking Loop
박민혁 Min-huck Park , 전상훈 Sang-hoon Jeon , 김종원 Chong-won Kim , 기창돈 Chang-don Kee , 서승우 Seung-woo Seo , 장재규 Jae-gyu Jang , 소형민 Hyoung-min So , 박준표 Jun-pyo Park
21(1) 43-49, 2017
박민혁 Min-huck Park , 전상훈 Sang-hoon Jeon , 김종원 Chong-won Kim , 기창돈 Chang-don Kee , 서승우 Seung-woo Seo , 장재규 Jae-gyu Jang , 소형민 Hyoung-min So , 박준표 Jun-pyo Park
DOI: JANT Vol.21(No.1) 43-49, 2017
Generally, loop filter based scalar tracking loops (LF-STL) have been used for global positioning system (GPS) signal tracking algorithm. This paper introduces the accuracy and robustness of linear-quadratic-Gaussian based vector tracking loop (LQG-VTL) algorithm instead of LF-STL. To verify the accuracy of LQG-VTL, we confirm that the measurements estimation errors of the LQG based scalar tracking loops (LQG-STL) are improved by more than 60 % compared to LF-STL. Also, when LQG-VTL is used, measurements estimation errors decrease compared to LQG-STL, and position/velocity estimation errors also decrease as the number of satellites increases. To verify the robustness of LQG-VTL, we confirm that LQG-VTL can estimate position/velocity and measurements successively compared to LF-STL in temporal signal attenuation of 30 dB-Hz during 4 seconds.
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T&E Process for Safety-Critical CNS/ATM Systems
강자영 Ja-young Kang , 김무근 Mu-geun Kim , 김영훈 Young-hoon Kim , 임인규 In-kyu Lim
21(1) 50-57, 2017
강자영 Ja-young Kang , 김무근 Mu-geun Kim , 김영훈 Young-hoon Kim , 임인규 In-kyu Lim
DOI: JANT Vol.21(No.1) 50-57, 2017
Recently, safety-critical aviation system development programs promoted domestically have been terminated in the middle stage or they have not been put to practical use at the final stage. The program failure may be caused by various factors, but this study focused on imperfect test and evaluation(T&E) procedures. In general, T&E process of a safety-critical system must be distributed throughout the entire life-cycle of the system, have a continuity in phases, and can be implemented in a variety of ways depending on the maturity of the system development and acquisition strategy. This paper aims to present a new strategy by analyzing the domestic and overseas T&E processes to reduce the risk of domestic safety-critical CNS/ATM system development program and increase the success rate of program. First, we discuss the verification and validation techniques for safety-critical systems, analyze the T&E procedures of advanced institutes and the domestic situation, and then compare the domestic and overseas T&E processes to complement the imperfect testing procedure.
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GNSS Techniques for Enhancing Flight Safety of UAS
박제홍 Je-hong Park
21(1) 58-65, 2017
박제홍 Je-hong Park
DOI: JANT Vol.21(No.1) 58-65, 2017
Global navigation satellite system (GNSS) has a weakness of signal integrity caused by broadcasting type data transmitting direct to user from navigation satellite. Loss of GNSS signal integrity can make a catastrophic event in the operation of unmanned aerial system (UAS) because position decision is only depended on GNSS. So it is required to apply alternative method to reduce a risk and to guarantee a GNSS signal integrity for UAS operation. This paper addressed the reason of loosing GNSS signal integrity, the effectiveness of signal jamming/spoofing and GNSS application trend for UAS. Also suggested the flight safety enhancing method in case of GNSS signal jamming for UAS as technical and political approaches.
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Implementation of An Water-Cooled High Power Amplifier for Particle Accelerator
윤영철 Young-chul Yoon , 김영 Young Kim
21(1) 66-71, 2017
윤영철 Young-chul Yoon , 김영 Young Kim
DOI: JANT Vol.21(No.1) 66-71, 2017
This paper describes implementation of a 165 MHz, 5 kW RF high power amplifier (HPA) for particle accelerator applications. The HPA consists of a drive amplifier for main amplifiers driving, sixteen 600 W class-AB push-pull power amplifier pallets and Wilkinson power divider/combiner using lumped LC components, which are divided/combined power amplifier pallet outputs. To detected the amplifier circuit of normal and reflected output power conditions, we used a bidirectional coupler. To radiate heat of main power amplifier, we were used an water-cooled copper plates to go through a water for radiation of heat. The HPA of center frequency 165 MHz has archived an efficiency of 62.5 % at 5 kW of power level experimentally.
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IoT Platform and Control App Design for Wireless Data Transmission
노재성 Jae-sung Roh , 조영준 Young-joon Cho
21(1) 72-77, 2017
노재성 Jae-sung Roh , 조영준 Young-joon Cho
DOI: JANT Vol.21(No.1) 72-77, 2017
In recent years, internet of things (IoT) technology has developed rapidly and has been applied in many fields. IoT devices collect and analyze information in various environments and provide useful information to users. Due to the recent increase in IoT devices, many open source platforms based on hardware and software that are cheap and easy to use have been developed and provided. In this paper, we have studied the IoT system based on Arduino which can communicate Bluetooth wireless data with smart phone in real time. And we have developed a wireless system control app based on App Invertor 2 for communication with Android smart phone. Also, we propose an IoT system based on Arduino which can control the devices and implement the function of connectivity between devices.
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Analysis of Linux Service Management System According to Boot Process Change
정성재 Sung-jae Jung , 배유미 Yu-mi Bae , 소우영 Wooyoung Soh
21(1) 78-83, 2017
정성재 Sung-jae Jung , 배유미 Yu-mi Bae , 소우영 Wooyoung Soh
DOI: JANT Vol.21(No.1) 78-83, 2017
Linux was born under the influence of Unix except for the kernel, Linux was used to bring the Unix system and relevant program package, commands, etc. However, the latest version of Enterprise Linux, RHEL 7 was adopted systemd instead of init to boot program and management services. The adoption of systemd was building its own Linux system, the system only. Also noteworthy point is that given the considerable number of features specific to a particular package and instructions. As Linux has been recognized as a subtype of Unix itself as a catch all this time the turn of the tide in the cloud era and there on their own to try various changes, the start of the adoption of these changes can be called systemd. Linux is the future beyond the confines of Unix is noteworthy not attempt any changes.
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Dual-Wideband Bandpass Filter Using Distributed Composite Right/Left-Handed Transmission Line Quad-Mode Resonators
성규제 Gyuje Sung , 김영 Young Kim
21(1) 84-89, 2017
성규제 Gyuje Sung , 김영 Young Kim
DOI: JANT Vol.21(No.1) 84-89, 2017
This paper presents a dual-wideband bandpass filter (BPF) with high band-to-band isolation and skirt selectivity using distributed composite right/left-handed (CRLH) transmission line (TL) quad-mode resonators (QMRs). The results of the proposed distributed CRLH TL unit cell analysis are used to establish the scattering parameters and the resonance frequencies of the QMR constituting the dual-wideband BPF. A novel dual-wideband bandpass filter is designed and fabricated, using the derived scattering characteristics. The measured results show that the fabricated dual-wideband bandpass filter has an insertion loss of less than 1.08dB in the lower band, and of 2.01dB in the upper band, a bandwidth of 2.8-5.52GHz and 9.68-12.26GHz, and a band-to-band isolation of more than 38dB, from 6.34-8.42GHz.
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Air Traffic Controllers` Fatigue and Stress based on Heart Rate Measurement
박진한 Jin-han Park , 안덕배 Deok-bae An , 백호종 Hojong Baik
21(1) 90-98, 2017
박진한 Jin-han Park , 안덕배 Deok-bae An , 백호종 Hojong Baik
DOI: JANT Vol.21(No.1) 90-98, 2017
This paper is concerned with air traffic controllers` fatigue and stress that they experience during their daily job particularly as being shift workers. Previous researches reveal that the controllers` fatigue and stress increase by several factors including time spent at work, traffic intensity, visibility, etc. The researches also indicate that air traffic controllers` fatigue and stress can be reasonably surrogated by their heart rate. We set three hypotheses relating the influencing factors and the fatigue and stress represented by the heart rates. Using wrist bands, air traffic controllers` heart rates at various situations are collected at Choongju airport. The hypothetical tests explicitly confirm that the heart rate is highly correlated with the traffic level and the time spent at work. In particular, it be shown that even when handling the same traffic level, air traffic controllers` stress level increases as the time they spent at work increases.
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An Energy Harvesting and Profiling System for Smart Video Devices
강두식 Doo-sik Kang , 김준식 Jun-sik Kim , 박건우 Keon-woo Park , 이명진 Myeong-jin Lee
21(1) 99-106, 2017
강두식 Doo-sik Kang , 김준식 Jun-sik Kim , 박건우 Keon-woo Park , 이명진 Myeong-jin Lee
DOI: JANT Vol.21(No.1) 99-106, 2017
In this paper, an energy harvesting and profiling system is designed for smart video devices in internet of things environments without dedicated power source. The energy harvesting module provides the harvested energy from solar panel to the smart video device. The energy profiling module measures the battery outflow current and the battery voltage of the smart video device and the consumed energy of processes, and calculate the harvested energy from the energy harvesting module to the smart video device and the total energy consumption of the smart video device. The accuracy of the harvested energy measured by the device energy profiling module is validated by comparing with the calculated energy using the regional solar radiation provided by Korea Meteorological Administration. Energy harvesting data from the designed energy harvesting and profiling system can be used to design the perpetual operation of smart video devices or Internet of Things sensors.
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Implementation of Leakage Monitoring System Using ZigBee
주재한 Jae-han Ju , 나승권 Seung-kwon Na
21(1) 107-112, 2017
주재한 Jae-han Ju , 나승권 Seung-kwon Na
DOI: JANT Vol.21(No.1) 107-112, 2017
In recent years, electric shock accidents due to electric leakage currents of household appliances such as computers, TVs, refrigerators, and LED lights are continuously occurring in homes and industrial buildings. And it is not easy to check the leakage current of each household appliances connected in parallel at the rear end of the module. In addition, the leakage current flowing through the path of the normal current other than the existing current leakage circuit breakers are installed in the distribution box, only the function to cut off the power when the leakage. Therefore, there are various disasters such as electric shock and fire caused by short circuit of household appliances, and the risk of such leakage current is seriously presented. In this paper, we propose a method to implement a leakage monitoring system that can be monitored at all times using Zigbee communication based on IEEE 80215.4, which has advantages in low power and low cost among short range wireless communication systems.
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Implementation of VoIP Service in Hybrid Fiber Coaxial Network
주재한 Jae-han Ju
21(1) 113-118, 2017
주재한 Jae-han Ju
DOI: JANT Vol.21(No.1) 113-118, 2017
As interest in mobile devices and networks has increased recently, voice over internet protocol (VoIP) service, which is a technology for transmitting voice data using an existing internet protocol (IP) network, has rapidly spread, Cheap voice call service has become possible. As the digital broadcasting service becomes popular, hybrid fiber coaxial (HFC) network technology, which uses broadband cable network through fusion of broadcasting and communication, utilizes existing communication system and network equipment to provide various new services such as interactive broadcasting service. Therefore, if UGS-AD is applied to VoCM and RTPS is applied to MTA in order to guarantee the quality of voice data in actual HFC Internet service network, it is possible to smoothly perform voice data transmission in narrow upstream band which is a problem in actual commercial HFC network We also proposed a method to improve VoIP service by improving QoS of voice data in HFC Internet service network.
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Merge and Split of Players under MeanShift Tracking in Baseball Videos
최현영 Hyeon-yeong Choi , 홍성화 Sung-hwa Hong , 고재필 Jae-pil Ko
21(1) 119-125, 2017
최현영 Hyeon-yeong Choi , 홍성화 Sung-hwa Hong , 고재필 Jae-pil Ko
DOI: JANT Vol.21(No.1) 119-125, 2017
In this paper, we propose a method that merges and splits players in the MeanShift tracking framework. The MeanShift tracking moves the center of tracking window to the maximum probability location given the target probability distribution. This tracking method has been widely used for real-time tracking problems because of its fast processing speed. However, it hardly handles occlusions in multiple object tracking systems. Occlusions can be usually solved by applying data association methods. In this paper, we propose a method that can be applied before data association methods. The proposed method automatically merges and splits the overlapped players by adjusting the each player`s tracking map. We have compared the tracking performance of the MeanSfhit tracking algorithm and the proposed method.
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Design of a Smart Safety Measurement System Using Bluetooth Beacon Sensor Nodes
박영수 Young-soo Park , 박창진 Chang-jin Park , 조선희 Sun-hee Cho , 박경용 Kyoung-yong Park , 김민선 Min-sun Kim , 서정욱 Jeongwook Seo
21(1) 126-131, 2017
박영수 Young-soo Park , 박창진 Chang-jin Park , 조선희 Sun-hee Cho , 박경용 Kyoung-yong Park , 김민선 Min-sun Kim , 서정욱 Jeongwook Seo
DOI: JANT Vol.21(No.1) 126-131, 2017
This paper designs a smart safety measurement system with Bluetooth beacon sensor nodes that can provide risk detection and evacuation/countermeasure services. The Bluetooth beacon sensor nodes is easily able to be attached to old building wall or construction or civil structure with potential danger. The proposed smart safety measurement system transmits various sensor data such as acceleration, gyroscope, geomagnetic, pressure, altitude, temperature, humidity at the spot where Bluetooth beacon sensor nodes are installed, and we can use them for risk perception, prediction, and warning services. To verify the effectiveness of the proposed system, we performed filed tests which showed that measured displacement values of precast retaining walls were within the permitted displacement value of 38.5 mm.
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Real-Time CoM/ZMP Trajectory Transformation Method for Humanoid Robots Considering Structure Characteristics
홍석민 Seok-min Hong
21(1) 132-137, 2017
홍석민 Seok-min Hong
DOI: JANT Vol.21(No.1) 132-137, 2017
This paper proposes a transformation method of the zero moment point (ZMP) and the center of mass (CoM) from one walking pattern to other patterns by considering the structure of a robot or walking situations in real time. In general, a humanoid robot has own structure characteristics like height and mass. The structure characteristics make the given CoM/ZMP walking pattern of one human or one humanoid robot to be difficult to apply to other robot directly. For this purpose, we analyze the characteristics of walking patterns according to the step length, duration of walking support phase and the CoM height by using the cart-table model as the simple humanoid robot model. A transformation equation is derived from the analyzation and it is verified with simulation.
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Improving INS/GPS Integrated System Position Error using Dilution of Precision
김현석 Hyun-seok Kim , 백승준 Seung-jun Baek , 조윤철 Yun-cheol Cho
21(1) 138-144, 2017
김현석 Hyun-seok Kim , 백승준 Seung-jun Baek , 조윤철 Yun-cheol Cho
DOI: JANT Vol.21(No.1) 138-144, 2017
A method for improving the integrated navigation performance in the INS/GPS navigation system by the considering that the condition that the geometric arrangement of the satellite is degraded due to limitation of the line of sight of the satellite such as geographic feature and GPS signal jamming is proposed. A variable covariance extended Kalman filter (VCEKF) that correlated to the measured covariance to the DOP of GPS is suggested. The navigation performance of integrated navigation system using EKF and VCEKF is analyzed by Monte-Carlo simulations. The result is verified that VCEKF has better estimation performance than EKF using fixed covariance on condition that DOP value is larger than the smaller value.
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Application of the Small UAV Defense System
박제홍 Jehong Park
21(1) 145-152, 2017
박제홍 Jehong Park
DOI: JANT Vol.21(No.1) 145-152, 2017
As a popularization of small UAS to have improved flight performance and easiness of controlling, the UAS industry is increased and also small UAS is to be a new threat for airspace security of national strategic infrastructure. Rising the new threat makes the negative side effect of small UAS operation. This phenomena brought to new R&D needs “defense system” for small UAS/UAV - called Anti-Drone. The paper addressed case study of defects, accidents and threats by small UAS/UAV as world wide level, and research and development trend of UAS defense system as each technical category - CONOP (Concept of Operation), identification/recognition method and control/supremacy techniques. As a result, this suggests the direction what and where drone defense system should be applied first and required for Korean society in the view of society system (regime) and a point of view for minimizing side effect as UAS popularization.
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