• Title/Summary/Keyword: time-of -flight

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Prediction of the Flight Times of Hydrochara affinis and Sternolophus rufipes in Paddy Fields Based on RCP 8.5 Scenario (RCP 8.5 기후변화 시나리오를 적용한 논 서식 애물땡땡이 (Sternolophus rufipes)와 잔물땡땡이(Hydrochara affinis)의 비행시기 예측)

  • Choi, Soon-Kun;Kim, Myung-Hyun;Choe, Lak-Jung;Eo, Jinu;Bang, Hea-Son
    • Korean Journal of Agricultural and Forest Meteorology
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    • v.18 no.1
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    • pp.16-29
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    • 2016
  • The total area of paddy field was estimated to be 55 % of the cultivated lands in South Korea, which is approximately 1 million hectares. Organisms inhabiting paddy fields if they are sensitive to environmental changes can be environmental indicator of paddy fields. Biological indicators such as phenology and distributional range are evaluated as intuitive and quantitative method to analyze the impact of climate change. This study aims to estimate flight time change of Hydrophilidae species' based on the RCP 8.5 climate change scenario. Unmanned monitoring systems were installed in Haenam, Buan, Dangjin and Cheorwon relative to the latitudinal gradient. In the three regions excepting Cheorwon, it was able to measure the abundance of flying Hydrochara affinis and Sternolophus rufipes. Degree-day for the flight time was determined based either on field measurement values and estimates of 2020s, 2050s and 2080s from KMA climate change scenario data. As a result, it is found that date of both species of initial flight becomes 15 days earlier, that of peak flight becomes 22 days earlier and that of final flight does 27 days earlier in 2080s compared to 2020s. The climate change impact on flight time is greater in coastal area, rural area and valley than inland area, urban area and plan. H. affinis and S. rufipes can be used as climate change indicator species.

A Study on the Aptitude Test of Remotely Piloted Aircraft Pilots (Focused on Selection of Aptitude Test Items) (원격조종항공기조종사 적성검사에 관한 연구 (적성검사 항목선정을 중심으로))

  • Park, Won-Tae;Lee, Kang-Seok
    • Journal of the Korean Society for Aviation and Aeronautics
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    • v.23 no.1
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    • pp.30-40
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    • 2015
  • Recently, the need of RPA(Remotely Piloted Aircraft) pilots is increasing rapidly with many requirements in order to be a beginner RPA pilot, including basic flight training, instrument flight qualification training, and aircraft type switching training. When RPA pilot gets disqualified, there will be generated much waste of efforts and expenses of trainees those pilots who are disqualified. Therefore, the methodology of pre-verifying those pilots who are not proper as RPA pilots through various scientific methods will save time and expenses with pre-reducing the pilots who will get disqualified later on. The methodology of aptitude test of RPA pilots is laid out as a consideration of pre-study of RPA pilots work analysis, and select types of aptitude test. A suitability of aptitude test is verified. In order to diagnose the flight aptitude precisely, it requires to be developed. Flight aptitude test tools might be connected with training program which could foster piloting aptitude with pre-diagnosing RPA pilot trainee selecting process. For that reason, we made an experiment in order to verify credibility and suitability of these selected programs with developing RPA pilot aptitude test tools. And also, we analyzed relationships among characteristics, analysis of data, and variables to verify the efficiency of data from prior experiment. Through this thesis, we expect to raise efficiency of flight training by providing pre-flight aptitude test information of RPA pilots.

Optimized Air Force Flight Scheduling Considering Pilot' s Mission Efficiency (조종사 임무 효율을 고려한 공군 비행 스케줄 최적화)

  • Kwon, Min Seok;Yoon, Chan Il;Kim, Jiyong
    • Journal of Korean Society of Industrial and Systems Engineering
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    • v.43 no.4
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    • pp.116-122
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    • 2020
  • Human and material resource planning is one representative example of Operations Research. Resource planning is important not only in civilian settings but also in military ones. In the Air Force, flight scheduling is one of the primary issues that must be addressed by the personnel who are connected to flight missions. However, although the topic is of great importance, relatively few studies have attempted to resolve the problem on a scientific basis. Each flight squadron has its own scheduling officers who manually draw up the flight schedules each day. While mistakes may not occur while drafting schedules, officers may experience difficulties in systematically adjusting to them. To increase efficiency in this context, this study proposes a mathematical model based on a binary variable. This model automatically drafts flight schedules considering pilot's mission efficiency. Furthermore, it also recommends that schedules be drawn up monthly and updated weekly, rather than being drafted from scratch each day. This will enable easier control when taking the various relevant factors into account. The model incorporates several parameters, such as matching of the main pilots and co-pilots, turn around time, availability of pilots and aircraft, monthly requirements of each flight mission, and maximum/minimum number of sorties that would be flown per week. The optimal solution to this model demonstrated an average improvement of nearly 47% compared with other feasible solutions.

A Study on the Use of Drones for Disaster Damage Investigation in Mountainous Terrain (산악지형에서의 재난피해조사를 위한 드론 맵핑 활용방안 연구)

  • Shin, Dongyoon;Kim, Dajinsol;Kim, Seongsam;Han, Youkyung;Nho, Hyunju
    • Korean Journal of Remote Sensing
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    • v.36 no.5_4
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    • pp.1209-1220
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    • 2020
  • In the case of forest areas, the installation of ground control points (GCPs) and the selection of terrain features, which are one of the unmanned aerial photogrammetry work process, are limited compared to urban areas, and safety problems arise due to non-visible flight due to high forest. To compensate for this problem, the drone equipped with a real time kinematic (RTK) sensor that corrects the position of the drone in real time, and a 3D flight method that fly based on terrain information are being developed. This study suggests to present a method for investigating damage using drones in forest areas. Position accuracy evaluation was performed for three methods: 1) drone mapping through GCP measurement (normal mapping), 2) drone mapping based on topographic data (3D flight mapping), 3) drone mapping using RTK drone (RTK mapping), and all showed an accuracy within 2 cm in the horizontal and within 13 cm in the vertical position. After evaluating the position accuracy, the volume of the landslide area was calculated and the volume values were compared, and all showed similar values. Through this study, the possibility of utilizing 3D flight mapping and RTK mapping in forest areas was confirmed. In the future, it is expected that more effective damage investigations can be conducted if the three methods are appropriately used according to the conditions of area of the disaster.

A Study on Verify of UAV Flight Control Software Simulated Flight using Model-Based Development and X-Plane simulator (모델기반 개발기법과 X-plane을 이용한 무인항공기 비행제어 프로그램 모의비행 검증)

  • Han, Dong-In;Kim, Young-Sik;Lee, Chang-Yong;Lee, Dae-Woo;Cho, Kyeum-Rae
    • Journal of the Korean Society for Aeronautical & Space Sciences
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    • v.43 no.2
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    • pp.166-171
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    • 2015
  • This paper shows the design of operational flight program(OFP) using model-based design(MBD) method which is used in various engineering fields to reduce time and flight risks for development. The verification of OFP for DO-178C guidelines carry out by a model advisor function of simulink. The flight control logic on simulink is converted into C-language by auto code generation tool from, then it is implemented on 32bit digital signal processor(DSP). The verifications of flight control algorithm on various weather conditions are performed by the HILS system with Flight simulator program, X-plane.

A Research on Aerial Refueling Type and Flight Testing of Boom-Receptacle Systems for a Fixed-wing Aircraft (고정익 항공기 공중급유 유형 및 Boom-Receptacle 시스템 비행시험 평가 방안 연구)

  • Kim, Dae-wook;Kim, Chan-jo
    • Journal of Aerospace System Engineering
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    • v.16 no.1
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    • pp.70-80
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    • 2022
  • An aerial refueling provides for extension of operational time and range for aircraft and enhances mission effectiveness, hence it application by most military aircrafts. The receiver aircraft should have the aerial refueling clearance that is established by performing technical and operational compatibility assessments to certify it for aerial refueling with a specific tanker model. The compatibility assessment includes aerial refueling handling qualities, functional, fuel, lighting system testing and it is finally verified through flight testing. However, since aerial refueling compatibility assessments have never been performed in Korea, there is no experience to determine the test requirements and the scope and size of the test program for a new development aircraft. This paper therefore introduces the common techniques of aerial refueling and aerial refueling flight test methods to understand the aerial refueling FCS (Flight Control System), OFP (operational flight program) and system validation, and aerial refueling envelope clearance of a fixed wing aircraft for a boom and receptacle refueling system that is being introduced into Korea Air Force.

The Development of MILS Software based on RTX for Real-time Imitation of an Inertial Navigation System (관성항법장치의 실시간 모의를 위한 RTX기반의 MILS S/W 개발)

  • Kim, Ki-Pyo;Choi, Jin-Ho;Ahn, Kee-Hyun;Woo, Deog-Young
    • Journal of the Korea Institute of Military Science and Technology
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    • v.14 no.3
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    • pp.353-358
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    • 2011
  • In this paper, we have introduced a Missile In the Loop Simulation(MILS) Software developed for the missile ground test, which is based on a commercial hard real-time operating system(OS) on Windows platform called as Real-Time eXtension(RTX). MILS software makes it possible to test overall system functions of a integrated missile on the ground in the flight conditions by real-time imitating its inertial data. By means of MILS, we have performed missiles ground tests, which result in successful real flight tests.

Autostereoscopic 3D display system with moving parallax barrier and eye-tracking (이동형 패럴랙스배리어와 시점 추적을 이용한 3D 디스플레이 시스템)

  • Chae, Ho-Byung;Ryu, Young-Roc;Lee, Gang-Sung;Lee, Seung-Hyun
    • Journal of Broadcast Engineering
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    • v.14 no.4
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    • pp.419-427
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    • 2009
  • We present a novel head tracking system for stereoscopic displays that ensures the viewer has a high degree of movement. The tracker is capable of segmenting the viewer from background objects using their relative distance. A depth camera using TOF(Time-Of-Flight) is used to generate a key signal for eye tracking application. A method of the moving parallax barrier is also introduced to supplement a disadvantage of the fixed parallax barrier that provides observation at the specific locations.

Link Performance of an CDMA-Based Time-of-Flight Ranging by Using LED Visible Light

  • Wang, Yang;Liang, Chengchao;Su, Xin;Chang, KyungHi
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.37A no.10
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    • pp.834-840
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    • 2012
  • The use of ranging sensors on automobiles is becoming common with the desire of traffic safety by providing drivers the information of the relative distance between the vehicles. In this paper, the LED visible light ranging system different from the conventional ranging systems using the RF signal is investigated. For such a system, we propose a novel ranging algorithm which combines the time-of-flight (TOF) with the CDMA technology. Via the CDMA technology, the TOF ranging system can accurately distinguish the desired ranging signal from the visible light interferences of the neighbor vehicles. In addition, the proposed system can also overcome the light noise from other luminaries, i.e. sun-light, traffic-light, and so on. The simulation results show that the CDMA-based LED ranging system has a significant improvement for the ranging accuracy compared with the case without employing the CDMA.

FPGA Implementation of Differential CORDIC-based high-speed phase calculator for 3D Depth Image Extraction (3차원 Depth Image 추출용 Differential CORDIC 기반 고속 위상 연산기의 FPGA 구현)

  • Koo, Jung-youn;Shin, Kyung-Wook
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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    • 2013.10a
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    • pp.350-353
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    • 2013
  • In this paper, a hardware implementation of phase calculator for extracting 3D depth image from TOF(Time-Of-Flight) sensor is proposed. The designed phase calculator, which adopts redundant binary number systems and a pipelined architecture to improve throughput and speed, performs arctangent operation using vectoring mode of DCORDIC algorithm. Fixed-point MATLAB simulations are carried out to determine the optimized bit-widths and number of iteration. The designed phase calculator is verified by emulating the restoration of virtual 3D data using MATLAB/Simulink and FPGA-in-the-loop verification, and the estimated performance is about 7.5 Gbps at 469 MHz clock frequency.

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