• Title/Summary/Keyword: flight tests

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Research on Measures to Enhance Railroad Security Checks of Railroad Police Officers to Prevent Terrorist Attacks (철도테러 예방을 위한 철도경찰 보안검색 강화 방안 연구)

  • Gwon, Hyeon-Shik
    • Korean Security Journal
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    • no.49
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    • pp.157-183
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    • 2016
  • Countries across the globe, including those in Europe, are waging a "war against terrorism" as international terrorist groups such as ISIS and lone-wolf terrorists have unleashed various large-scale attacks on rail infrastructure. Anti-South Korean sentiment exists in Muslim-majority countries because the nation has cooperated with the US for its military interventions in the Middle East, and ISIS has threatened to target South Korea four times since September 9, 2015. In addition, North Korea has been left isolated in the international community with its missile and nuclear tests, while further escalating inter-Korean tension and threatening to strike major facilities and attack important figures in the South. These situations imply that South Korea is no longer immune to terrorist attacks. If the nation fails to prevent or deter such terrorist attacks against rail networks, massive casualties, property damage and social confusion would be unavoidable, deteriorating national and international trust in its counter-terrorism policies. This may lead to a national crisis involving decreases in the number of tourists, dampened interest of foreign investors, and capital flight. This study aims to propose policy measures to enhance railroad security checks, based on the work of railroad police officers, for the sake of protecting citizens and public safety. The suggestions include an incremental expansion of railroad security checks; growth of the railroad police force and adjustment of their policing distribution with other police officers; enhancement of security systems across important rail networks; improvement of the Railroad Safety Act; Southeast Asia, including the corresponding strengthening of the national crackdown illegal immigrants, and plans for pre-emptive and regular cooperation among organizations related to the promotion of security checks and the prevention of terrorist attacks.

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Sex Pheromone and Seasonal Occurrence of the peach leafminer, Lyonetia clerkella Linne (복숭아굴나방의 성페로몬과 성충 발생소장)

  • Yang Chang-Yeol;Jeon Heung-Yong;Kim Dae-Young;Kim Hyeong-Hwan
    • Korean journal of applied entomology
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    • v.45 no.1 s.142
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    • pp.25-30
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    • 2006
  • The female sex pheromone of the peach leafminer, Lyonetia clerkella Linne (Lepidoptera: Lyonetiidae), was analyzed by coupled gas chromatographic-electroantennographic detector (GC-EAD). GC-EAD analyses of pheromone gland extract revealed a single compound that elicited responses from male antennae. Retention time on DB-1 column of EAD-active compound was identical to that of synthetic (145)-14-Methyl-1-octadecene (14Sme-1-18Hy). In field tests, sticky traps baited with synthetic 14Sme-1-18Hy alone were highly attractive to male. Traps with 0.1 mg dose showed the lowest catches, but there were no significant difference in the numbers of moth caught in traps baited with doses of 0.5 and 1.0 mg. The results of the field assays for longevity of pheromone traps showed that effectiveness of lures maintained for at least 8 weeks under field condition. The attractiveness of 14Sme-1-18Hy was not affected by the addition of butylated hydroxytoluene (BHT) in lures as an antioxidant. Traps baited with 0.5 mg 14Sme-1-18Hy were successfully used to monitor L. clerkella male flights. Analysis of seasonal trap catches over two years showed that moth flight activity in peach orchards occurred over a period of seven months with six generations in Suwon.

Proteomic Analysis and the Antimetastatic Effect of N-(4methyl)phenyl-O-(4-methoxy) phenyl-thionocarbamate-Induced Apoptosis in Human Melanoma SK-MEL-28 cells

  • Choi Su-La;Choi Yun-Sil;Kim Young-Kwan;Sung Nack-Do;Kho Chang-Won;Park Byong-Chul;Kim Eun-Mi;Lee Jung-Hyung;Kim Kyung-Mee;Kim Min-Yung;Myung Pyung-Keun
    • Archives of Pharmacal Research
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    • v.29 no.3
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    • pp.224-234
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    • 2006
  • We employed human SK-MEL-28 cells as a model system to identify cellular proteins that accompany N-(4-methyl)phenyl-O-(4-methoxy)phenyl-thionocarbamate (MMTC)-induced apoptosis based on a proteomic approach. Cell viability tests revealed that SK-MEL-28 skin cancer cells underwent more cell death than normal HaCaT cells in a dose-dependent manner after treatment with MMTC. Two-dimensional electrophoresis in conjunction with matrixassisted laser desorption/ionization-time of flight (MALDI-TOF) mass spectrometry analysis or computer matching with a protein database further revealed that the MMTC-induced apoptosis is accompanied by increased levels of caspase-1, checkpoint suppressor-1, caspase-4, NF-kB inhibitor, AP-2, c-Jun-N-terminal kinase, melanoma inhibitor, granzyme K, G1/S specific cyclin D3, cystein rich protein, Ras-related protein Rab-37 or Ras-related protein Rab-13, and reduced levels of EMS (oncogene), ATP synthase, tyrosine-phosphatase, Cdc25c, 14-3-3 protein or specific structure of nuclear receptor. The migration suppressing effect of MMTC on SK-MEL-28 cell was tested. MMTC suppressed the metastasis of SK-MEL-8 cells. It was also identified that MMTC had little angiogenic effect because it did not suppress the proliferation of HUVEC cell line. These results suggest that MMTC is a novel chemotherapeutic and metastatic agents against the SK-MEL-28 human melanoma cell line.

Design and Development of VDL Mode-2 D8PSK Modem (VDL Mode-2 D8PSK 모뎀 설계 및 개발)

  • Gim, Jong-Man;Choi, Seoung-Duk;Eun, Chang-Soo
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.34 no.11C
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    • pp.1085-1097
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    • 2009
  • We present a structure and design method of the D8PSK modem compatible with the VDL mode-2 standard and performance test results of the developed modem. In VDL mode-2, the raised cosine filter is used only in the transmitter and a general low pass filter is used in the receiver. Consequently, we can not achieve ISI reduction but can have better spectrum characteristics. Although there is 1~2 dB performance degradation with an un-matched filter compared to that with a matched filter, it is more important to minimize adjacent channel interference in narrow band communications. The transmit signal is generated digitally to avoid the problems(I/Q imbalance and DC offset etc.) of analog modulators. In addition the digital down converter using digital IF sampling technique is adopted for the receiver. This paper contains the overall configuration, design method and simulation results based in part on the previously proposed structures and algorithms. It is confirmed that the modem transmits and receives messages successfully at a speed of max. 870 km/h over ranges of up to 310 km through the ground and in-flight communication tests.

Auto-Tracking Camera Gimbal for Power Line Inspection Drone and its Field Tests on 154 kV Transmission Lines (송전선로 자동추적 카메라 짐벌 및 154 kV 송전선로 현장시험)

  • Kim, Seok-Tae;Park, Joon-Young;Lee, Jae-Kyung;Ham, Ji-Wan
    • KEPCO Journal on Electric Power and Energy
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    • v.5 no.3
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    • pp.149-156
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    • 2019
  • In the field of maintenance of power transmission lines, drones have been used for their patrol and inspection by KEPCO since 2017. This drone technology was originally developed by KEPCO Research Institute, and now workers from four regional offices of KEPCO have directly applied this technology to the drone patrol and inspection tasks. In the drone inspection system, a drone with an optical zooming camera and a thermal camera can fly automatically along the transmission lines by the ground control system developed by KEPCO Research Institute, but its camera gimbal has been remotely controlled by a field worker. Especially the drone patrol and inspection has been mainly applied for the transmission lines in the inaccessible areas such as regions with river-crossings, sea-crossings and mountains. There are often communication disruptions between the drone and its remote controller in such extreme fields of mountain areas with many barriers. This problem may cause the camera gimbal be out of control, even though the inspection drone flies along the flight path well. In addition, interference with the reception of real-time transmitted videos makes the field worker unable to operate it. To solve these problems, we have developed the auto-tracking camera gimbal system with deep learning method. The camera gimbal can track the transmission line automatically, even when the transmitted video on a remote controller is intermittently unavailable. To show the effectiveness of our camera gimbal system, its field test results will be presented in this paper.

Study on the neutron imaging detector with high spatial resolution at China spallation neutron source

  • Jiang, Xingfen;Xiu, Qinglei;Zhou, Jianrong;Yang, Jianqing;Tan, Jinhao;Yang, Wenqin;Zhang, Lianjun;Xia, Yuanguang;Zhou, Xiaojuan;Zhou, Jianjin;Zhu, Lin;Teng, Haiyun;Yang, Gui-an;Song, Yushou;Sun, Zhijia;Chen, Yuanbo
    • Nuclear Engineering and Technology
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    • v.53 no.6
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    • pp.1942-1946
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    • 2021
  • Gadolinium oxysulfide (GOS) is regarded as a novel scintillator for the realization of ultra-high spatial resolution in neutron imaging. Monte Carlo simulations of GOS scintillator show that the capability of its spatial resolution is towards the micron level. Through the time-of-flight method, the light output of a GOS scintillator was measured to be 217 photons per captured neutron, ~100 times lower than that of a ZnS/LiF:Ag scintillator. A detector prototype has been developed to evaluate the imaging solution with the GOS scintillator by neutron beam tests. The measured spatial resolution is ~36 ㎛ (28 line pairs/mm) at the modulation transfer function (MTF) of 10%, mainly limited by the low experimental collimation ratio of the beamline. The weak light output of the GOS scintillator requires an enormous increase in the neutron flux to reduce the exposure time for practical applications.

Improvement of Transfer Alignment Performance for Airborne EOTS (항공용 전자광학추적장비의 전달정렬 성능 개선)

  • Kim, Minsoo;Lee, Dogeun;Jeong, Chiun;Jeong, Jihee
    • Journal of Aerospace System Engineering
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    • v.16 no.4
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    • pp.60-67
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    • 2022
  • An Electro-Optical Tracking System (EOTS) is an electric optical system with EO/IR cameras, laser sensors, and an IMU. The EOTS calculates coordinates of targets, using attitude and acceleration measured by the IMU. In particular for an armed aircraft, the performance of the weapon system depends on how quickly and accurately it acquires the target coordinates. The IMU should be operated after alignment is complete, to meet the coordinate accuracy required by the weapon system so the initial stabilization time of the IMU should be reduced, by quickly measuring the attitude and acceleration. Alignment is the process of determining the initial attitude by resolving the attitude error of the IMU, and the IMU of mission equipment such as an airborne EOTS, uses velocity matching based on the velocity from GPS/INS for aircraft navigation. In this paper, a method is presented to improve the transfer alignment performance of the airborne EOTS, by maneuvering aircraft and the mission equipment. First, the performance factor of the alignment was identified, as a heading error through the velocity matching model and simulation results. Then acceleration maneuvers and attitude changes were necessary, to correct the error. As a result of flight tests applied to an EOTS on a OOO aircraft system, the transfer alignment performance was improved as the duration time was decreased, by more than five times when the aircraft accelerated by more than 0.2g and the EOTS was moving until 6.7deg/s.

Methodology of Test for sUAV Navigation System Error (소형무인항공기 항법시스템오차 시험평가 방법)

  • SungKwan Ku;HyoJung Ahn;Yo-han Ju;Seokmin Hong
    • Journal of Advanced Navigation Technology
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    • v.25 no.6
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    • pp.510-516
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    • 2021
  • Recently, the range of utilization and demand for unmanned aerial vehicle (UAV) has been continuously increasing, and research on the construction of a separate operating system for low-altitude UAV is underway through the development of a management system separate from manned aircraft. Since low-altitude UAVs also fly in the airspace, it is essential to establish technical standards and certification systems necessary for the operation of the aircraft, and research on this is also in progress. If the operating standards and certification requirements of the aircraft are presented, a test method to confirm this should also be presented. In particular, the accuracy of small UAV's navigation required during flight is required to be more precise than that of a manned aircraft or a large UAV. It was necessary to calculate a separate navigation error. In this study, we presented a test method for deriving navigation errors that can be applied to UAVs that have difficulty in acquiring long-term operational data, which is different from existing manned aircraft, and conducted verification tests.