• International journal of advanced smart convergence
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• v.9 no.3
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• pp.207-214
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• 2020

Currently, the operation of unmanned aerial vehicle (UAV) is regulated to be able to fly only within the visible range, but in recent years, the needs for operation in the invisible area, in the urban area and at night have increased. In order to operate UAVs in the invisible area, at night, and in the urban area, a flight path for UAVs must be prepared like those operated by manned aircraft, and for this, it is necessary to establish an unmanned aircraft system traffic management (UTM). In order to establish the UTM, information on the minimum separation distance to prevent collisions with UAVs and buildings is required, and accordingly, information on the navigation performance of UAVs is required. In order to analyze the navigation performance of an UAV, total system error (TSE), which is the difference between the planned flight path and the actual location of the UAV, is required. If the collected data are insufficient and classification according to integrity, independence, and direction is not performed, accurate navigation performance is not derived. In this paper, propose a navigation performance analysis method of UAV that is derived TSE using flight data and modeled with normal distribution, analyze performance.

• Journal of Mechanical Science and Technology
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• v.17 no.5
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• pp.654-667
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• 2003

This paper presents a consequence of the systematic approach to identify the aerodynamic parameters of an unmanned aerial vehicle (UAV) equipped with the automatic flight control system. A 3-2-1-1 excitation is applied for the longitudinal mode while a multi-step input is applied for lateral/directional excitation. Optimal time step for excitation is sought to provide the broad input bandwidth. A fully automated programmed flight test method provides high-quality flight data for system identification using the flight control computer with longitudinal and lateral/directional autopilots, which enable the separation of each motion during the flight test. The accuracy of the longitudinal system identification is improved by an additional use of the closed-loop flight test data. A constrained optimization scheme is applied to estimate the aerodynamic coefficients that best describe the time response of the vehicle. An appropriate weighting function is introduced to balance the flight modes. As a result, concurrent system models are obtained for a wide envelope of both longitudinal and lateral/directional flight maneuvers while maintaining the physical meanings of each parameter.

• Archives of Pharmacal Research
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• v.27 no.2
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• pp.164-168
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• 2004

The chromatographic separation of the MeOH extract of the aerial parts of Solidago virga-aurea var. gigantea $M_{IQ}$ . (Compositae) led to the isolation of six terpenoids and four phenolic compounds, trans-phytol (1), ent-germacra-4(15),5,10(14 )-trien-1$\alpha$-ol (2), $\beta$-amyrin acetate (3), ent-germacra-4(15),5,10(14)-trien-1$\beta$-ol (4), $\beta$-dictyopterol (5), oleanolic acid (6), kaempferol (7), kaempferol-3-O-rutinoside (8), methyl 3,5-di-O-caffeoyl quinate (9), and 3,5-di-O-caffeoyl quinic acid (10). Their structures were established by chemical and spectroscopic methods. Compounds 4, 5, and 10 showed moderate cytotoxicity against five cultured human tumor cell lines in vitro with its E $D_{50}$ values ranging from 1.52∼18.57 $\mu\textrm{g}$/mL.L.

• Korean Journal of Pharmacognosy
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• v.39 no.2
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• pp.91-94
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• 2008

Column chromatographic separation of the MeOH extract from the aerial parts of Paris verticillata led to the isolation of three phenolics, two terpene glucosides and two pyrrolidine alkaloids. Their structures were characterized to be methyl caffeate (1), 5-hydroxy pyrrolidin-2-one (2), vanillic acid (3), benzyl alcohol glucopyranoside (4), (6S, 9R)-roseoside (5), staphylionoside H (6) and 5-methoxy pyrrolidin-2-one (7) by spectroscopic means. The isolated compounds (1-7) were for the first time reported from this source. The isolated compounds were tested for their cytotoxicity against four human tumor cell lines by SRB method in vitro.

• JSTS:Journal of Semiconductor Technology and Science
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• v.5 no.4
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• pp.243-248
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• 2005

The UAV (Unmanned Aerial Vehicle) systems like unmanned autonomous helicopters are used in various missions of flight navigation and used to collect the environmental information of the surroundings. To realize the full functionalities of the UAV, the software part becomes a challenging problem. In this paper embedded real-time software architecture for unmanned autonomous helicopter is proposed that guarantee real-time performance of hard-real time tasks and re-configurability of soft-real time and non-real time tasks. The proposed software architecture has four layers: hardware, execution, service agent and remote user interface layer according to the reactiveness level for external events. In addition, the layered separation of concurrent tasks makes different kinds of mission reconfiguration possible in the system. An Unmanned autonomous helicopter system was implemented (Kyosho RC Helicopter) in our lab to test and evaluate the performance of the proposed system.

• YAKHAK HOEJI
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• v.43 no.1
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• pp.5-10
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• 1999

As one of the serial studies on the specific and indigenous plants of Mt. Chiri the constituents of aerial part from filipendula formosa (Rosaceae) were investigated. From of the MeOH extract, five flavonol glycosides, kaempferol-3-O-$\beta$-D-galactopyranoside, querecetin-3-O-$\beta$-D-galactopyranoside, quercetin-3-O-$\alpha$-Lrhamopyranosyl (1 6)-$\beta$-D-galactopyranoside, kaempferol-3-O-$\alpha$-L-rhamnopyranosyl (1 6)-$\beta$-D-galactopyranoside and quercetin-7-O-$\beta$-D-glucopyranosy-3-O-$\beta$-D-galactopyranoside were isolated by column chromatographic separation using Amberlite XAD-2 and Sephadex LH-20, and identified physicochemical evidences (IR, FAB-Mass, $^1H,{\;}^{13}C-NMR$).

• Proceedings of the PSK Conference
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• 2003.10b
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• pp.193.1-193.1
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• 2003

Activity-guided separation for the aerial parts of Rodgersia podophylla A. Gray gave a new acylated flavonoid, quercetin 3-O-${\alpha}$-L-(5$^2$-acetyl)-arabinofuranoside (1), together with six known flavonoids (2-7). Their hepatoprotective activities were determined by using the primary cultures of rat hepatocytes injured by H$_2$O$_2$. Quercetin 3-O-${\alpha}$-L-(3$^2$-acetyl)-arabinofuranoside (3), kaempferol 3-O-${\alpha}$-L-rhamnopyranoside (5) and quercetin 3-O-${\alpha}$-L-rhamnopyranoside (6) exhibited hepatoprotective activities comparable to silybin at the concentration of 50 mM (45.7, 50.8 and 57.3 %, respectively), and the new flavonoid 1 showed hepatoprotective activity at the concentration of 100mM (50.1%).

• Electronics and Telecommunications Trends
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• v.36 no.4
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• pp.13-22
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• 2021

Among the activities of 3GPP for operating 5G-based unmanned aerial vehicles, we introduce several use cases of UAVs in 5G mobile communication such as radio access node onboard UAV, simultaneous support data transmission for UAVs and eMBB users, autonomous UAVs controlled by AI, isolated deployment of radio access through UAV, and separation of UAV service area. From this, we further summarize 5G mobile communication requirements for UAVs, including definition and operational criteria of UAS, UAS remote identification requirements, UAS usage requirements, and performance requirements. Finally, regarding 5G mobile communication-based UAS connectivity, identification and tracking support, we discuss the 3GPP UAV architecture, seven major problems, the proposed solutions to each problem, and propose the results for future specification work.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.30 no.7
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• pp.130-136
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• 2002

In this paper, a flight test method is described for the system identification of the unmanned aerial vehicle equipped with an automatic flight control system. Multistep inputs are applied for both longitudinal mode and lateral/directional excitation. Optimal time step for excitation is sought to provide the broad input bandwidth. A programmed mode flight test method provides high-quality flight data for system identification using the flight control computer with the longitudinal and lateral/directional autopilot which enables the separation of each motion during the flight test. In addition, exact actuating input that is almost equivalent to the designed one guarantees the highest input frequency attainable. Several repetitive flight tests were implemented in the calm air in order to extract the consistent system model for the air vehicle. The enhanced airborne data acquisition system endowed the high-quality flight data for the system identification. The flight data were effectively used to the system identification of the unmanned aerial vehicle.

• Journal of Advanced Navigation Technology
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• v.27 no.6
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• pp.763-769
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• 2023

Flight control computers for unmanned aerial vehicles are avionics that require high reliability and are generally designed to be multiplexed for margins on failures. The multiplexed flight control computer should include an interface through discrete signals and CCDL for synchronization and fault separation between channels. With the development of unmanned aerial vehicle technology, various types of platforms such as AAM and LPI are being developed in the private and military, which require advanced control performance for high-performance flight control and SWaP optimization of onboard equipment. In this paper, we designed a optimized flight control computer architecture for unmanned aerial vehicles for multiplexing processing and performed a software design for input and output control. In addition, input/output processing performance was evaluated through the implemented flight control computer and input/output software.