• Title/Summary/Keyword: aerial control

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System Improvement for Application and Diffusion of Earthwork Surveying Automation Technology (토공측량 자동화 기술의 적용 활성화를 위한 제도개선 방안)

  • Lee, Du-Heon;Park, Jae-Woo
    • The Journal of the Korea Contents Association
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    • v.18 no.6
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    • pp.303-313
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    • 2018
  • The purpose of this study is digitalization of earthwork such as development of 3D terrain analysis platform using latest technologies including unmanned aerial vehicle and terrestrial laser scanner to ultimately achieve earthwork automation. It is necessary to develop related element technologies and to establish regulations so that it can be applied to the domestic construction projects. As a result of pilot project about the earthwork surveying automation technology, it was confirmed that information such as terrain coordinates, soil, boring, and excavation volume is acquired smoothly. In this paper, we investigate related regulations and manuals in Japan and propose the improvement plan of domestic regulation. We plan to study regulations from early to final construction stage, combine with the 'regulation for public surveying', and improve the regulations in detail.

Design and Performance Analysis of Common data link digital modem for surveillance UAVs (정찰용 무인기를 위한 공용데이터링크 모뎀 설계 및 성능 분석)

  • Jung, Sungjin;Kim, Younggil;Lee, Daehong
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.22 no.1
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    • pp.162-168
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    • 2018
  • The UAV(Unmanned Aerial Vehicle) system, including the drone of a variety of fields, which has become an issue and utilized in various fields, has begun to develop in military fields and is actively developed in the commercial field. In various types of UAV systems, which have been developed recently, the communication system that is responsible for the connection between the ground control unit and the UAVs is called the data link. Especially, common data link used in military UAVs is required stability of communication to transmit surveillance and reconnaissance intelligence information and UAV's status. In this paper, the requirement for a modem was defined to secure the communication stability of the common data link used in surveillance UAVs. And, the design of the data link modem to satisfy applicable specifications was proposed. The proposed modem design was verified through the performance measurement of the implemented systems.

Antioxidative Effects of Several Compositae Plants (수 종의 국화과 식물의 항산화 쵸과)

  • 천상욱;김영민;한승관;최성규
    • Korean Journal of Plant Resources
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    • v.17 no.1
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    • pp.14-19
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    • 2004
  • Aerial parts of Compositae plants were harvested from pastures and crop fields of Sunchon area at vegetative stage to determine their antioxidant activity. Among 13 species, three species Taraxacum officinate, Breea segeta, and Artemisia princeps were selected as potent plant materials. Through measurement by Rancimat and TBARS method, antioxidative effect was the greatest in Taraxacum officinate among plant species. Antioxidative index (AI) investigated by Rancimat showed Siegesbeckia glabrescensi was 1.51 while commonly-used antioxidants, BHT and ascorbic acid were 3.86 and 2.43, respectively. The highest TBARS value was also obtained from Taraxacum officinate(0.18) at 4 weeks after storage, indicating the plant had the strongest antioxidant activity during long time. Even though TBARS value (0.18) in Taraxacum officinate sample showed lower in all plants than two synthetic antioxidants(0.05-0.09), antioxidant activities of the plants were much higher than that of a control (1.01). The results suggest that the plants have antioxidant potential as an alternative natural antioxidant based on natural plant resources.

Steady-State/Transient Performance Simulation of the Propulsion System for the Canard Rotor Wing UAV during Flight Mode Transition

  • Kong, Changduk;Kang, Myoungcheol;Ki, Jayoung
    • Proceedings of the Korean Society of Propulsion Engineers Conference
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    • 2004.03a
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    • pp.513-520
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    • 2004
  • A steady-state/transient performance simulation model was newly developed for the propulsion system of the CRW (Canard Rotor Wing) type UAV (Unmanned Aerial Vehicle) during flight mode transition. The CRW type UAV has a new concept RPV (Remotely Piloted Vehicle) which can fly at two flight modes such as the take-off/landing and low speed forward flight mode using the rotary wing driven by engine bypass exhaust gas and the high speed forward flight mode using the stopped wing and main engine thrust. The propulsion system of the CRW type UAV consists of the main engine system and the duct system. The flight vehicle may generally select a proper type and specific engine with acceptable thrust level to meet the flight mission in the propulsion system design phase. In this study, a turbojet engine with one spool was selected by decision of the vehicle system designer, and the duct system is composed of main duct, rotor duct, master valve, rotor tip-jet nozzles, and variable area main nozzle. In order to establish the safe flight mode transition region of the propulsion system, steady-state and transient performance simulation should be needed. Using this simulation model, the optimal fuel flow schedules were obtained to keep the proper surge margin and the turbine inlet temperature limitation through steady-state and transient performance estimation. Furthermore, these analysis results will be used to the control optimization of the propulsion system, later. In the transient performance model, ICV (Inter-Component Volume) model was used. The performance analysis using the developed models was performed at various flight conditions and fuel flow schedules, and these results could set the safe flight mode transition region to satisfy the turbine inlet temperature overshoot limitation as well as the compressor surge margin. Because the engine performance simulation results without the duct system were well agreed with the engine manufacturer's data and the analysis results using a commercial program, it was confirmed that the validity of the proposed performance model was verified. However, the propulsion system performance model including the duct system will be compared with experimental measuring data, later.

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Antimicrobial Activities of Eight Compounds Purified from the Roots of Polygala tenuifolia Willdenow and the Aerial Bulbils of Dioscorea batatas Decene (원지와 영여자로부터 분리한 8종 화합물의 항균효과)

  • Chin, Hwi-Seung;Son, Rak-Ho;Lee, Yong-Hwa;Ham, Ah-Rom;Mar, Woong-Chon;Kim, Won-Ki;Nam, Kung-Woo
    • YAKHAK HOEJI
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    • v.54 no.2
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    • pp.106-111
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    • 2010
  • The chemical structures of eight compounds purified from two plants (Polygala tenuifolia Willdenow and Dioscorea batatas Decene) were determined and their anti-microbial activity against three microbial strains (Staphylococcus aureus, Pseudomonas aeruginosa, and Candida albicans) was tested. The three micro organisms were cultured in 96-well plates or Petri dishes without (control) or with the eight compounds added at concentrations of 100 to 0.01 ${\mu}M$ (wt/vol). The growth of the microorganisms in the medium was examined after a 24-h incubation. The inhibitory effect of each compound on the growth of the microorganisms was calculated from the optical density measured at 595 nm, turbidity, and size of the inhibition zone around the treated paper disc. The minimum inhiitory concentration (MIC) of compounds 4 to 7 against S. aureus was 0.08, 0.05, 1.3 and 0.02 ${\mu}M$, respectively, and 0.09, 0.1, 0.2 and 100 ${\mu}M$ against C. albicans. The $IC_{50}$ (50% inhibition) values of compounds 5 and 6 were 3.1 and 6.4 ${\mu}M$ against S. aureus, respectively, and 10 and 2.4 ${\mu}M$ against C. albicans. Therefore, compounds 4 to 6 were the most potent anti-microbial agents among the eight compounds tested.

A Study on Large Scale Digital Mapping Using High Resolution Satellite Stereo Images (고해상도 위성영상을 이용한 대축척 수치지도 제작에 관한 연구)

  • Sung Chun Kyoung;Yun Hong Sic;Cho Jae Myoung;Cho Jung Ho
    • Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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    • v.22 no.3
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    • pp.277-284
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    • 2004
  • The subject of this study is to apply experimentally In resolution stereo imagery of IKONOS to producing 1:50,000 scale maps for Munsan area in Paju, being near the Military Demarcation Line, is inaccessible for aerial photography. Ground control points were acquired from GPS surveying to perform geometric corrections on images. Digital maps were produced from IKONOS stereo imagery on the digital photographic workstation. From field investigation, RMS errors of the plane and vertical positions are estimated respectively at $\pm$1.706m and $\pm$1.231m, respectively. These plane and vertical accuracies are within the tolerance limits of those provided in the NGIS Digital Topographic Map Production Rules. Therefore this suggested method is recommended for producing the large scale digital maps of 'No flight' zone near the M.D.L.

Development of a Multi-View Camera System Prototype (다각사진촬영시스템 프로토타입 개발)

  • Park, Seon-Dong;Seo, Sang-Il;Yoon, Dong-Jin;Shin, Jin-Soo;Lee, Chang-No
    • Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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    • v.27 no.2
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    • pp.261-271
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    • 2009
  • Due to the recent rise of a need for 3 dimensional geospatial information on urban areas, general interest in aerial multi-view cameras has been on an increase. The conventional geospatial information system depends solely upon vertical images, while the multi-view camera is capable of taking both vertical and oblique images taken from multiple directions, thus making it easier for the user to interpret the object. Through our research we developed a prototype of a multi-view camera system that includes a camera system, GPS/INS, a flight management system, and a control system. We also studied and experimented with the camera viewing angles, the synchronization of image capture, the exposure delay, the data storage that must be considered for the development of the multi-view camera system.

Start and Idle Combustion Characteristics of Hydrogen Engine for the HALE UAV (고고도 무인기용 수소 엔진의 시동성 및 공회전 연소 특성)

  • Kim, Yong-Rae;Choi, Young;Lee, Janghee
    • Journal of the Korean Institute of Gas
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    • v.19 no.6
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    • pp.22-27
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    • 2015
  • Hydrogen features highest energy density per mass and is expected to be desirable as a fuel of HALE(High altitude long endurance) UAV(Unmanned aerial vehicle). A reciprocating internal combustion engine is known to be a reliable and economic power source for this kind of UAV. Therefore, the combination of hydrogen and engine is worth of doing research. Test bench with 2.4L Spark-Ignited engine was prepared for the experiment in which start and combustion characteristics at idle condition were examined in this study. Stable hydrogen supply system and a universal ECU(Engine control unit) were also utilized for the test engine. Equivalence ratio and spark timings at idle operation were investigated and compared to the data of gasoline engine. The results will be a starting point for full-scale research of hydrogen engine for HALE UAV.

Improvements on the Three-Dimensional Positioning of High Resolution Stereo Satellite Imagery (고해상도 스테레오 위성영상의 3차원 정확도 평가 및 향상)

  • Jeong, In-Jun;Lee, Chang-Kyung;Yun, Kong-Hyun
    • Korean Journal of Remote Sensing
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    • v.30 no.5
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    • pp.617-625
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    • 2014
  • The Rational Function Model has been used as a replacement sensor model in most commercial photogrammetric systems due to its capability of maintaining the accuracy of the physical sensor models. Although satellite images with rational polynomial coefficients have been used to determine three-dimensional position, it has limitations in the accuracy for large scale topographic mapping. In this study, high resolution stereo satellite images, QuickBird-2, were used to investigate how much the three-dimensional position accuracy was affected by the No. of ground control points, polynomial order, and distribution of GCPs. As the results, we can confirm that these experiments satisfy the accuracy requirements for horizontal and height position of 1:25,000 map scale.

Stemphylium Leaf Blight of Garlic (Allium sativum) in Spain: Taxonomy and In Vitro Fungicide Response

  • Galvez, Laura;Gil-Serna, Jessica;Garcia, Marta;Iglesias, Concepcion;Palmero, Daniel
    • The Plant Pathology Journal
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    • v.32 no.5
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    • pp.388-395
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    • 2016
  • The most serious aerial disease of garlic is leaf blight caused by Stemphylium spp. Geographical variation in the causal agent of this disease is indicated. Stemphylium vesicarium has been reported in Spain, whereas S. solani is the most prevalent species recorded in China. In this study, Stemphylium isolates were obtained from symptomatic garlic plants sampled from the main Spanish production areas. Sequence data for the ITS1-5.8S-ITS2 region enabled assignation of the isolates to the Pleospora herbarum complex and clearly distinguished the isolates from S. solani. Conidial morphology of the isolates corresponded to that of S. vesicarium and clearly discriminated them from S. alfalfae and S. herbarum on the basis of the size and septation pattern of mature conidia. Conidial morphology as well as conidial length, width and length:width ratio also allowed the Spanish isolates to be distinguished from S. botryosum and S. herbarum. Control of leaf blight of garlic is not well established. Few studies are available regarding the effectiveness of chemical treatments to reduce Stemphylium spp. incidence on garlic. The effectiveness of nine fungicides of different chemical groups to reduce Stemphylium mycelial growth in vitro was tested. Boscalid + pyraclostrobin (group name, succinate dehydrogenase inhibitors + quinone outside inhibitors), iprodione (dicar-boximide), and prochloraz (demethylation inhibitors) were highly effective at reducing mycelial growth in S. vesicarium with $EC_{50}$ values less than 5 ppm. In general, the effectiveness of the fungicide was enhanced with increasing dosage.