• Title/Summary/Keyword: Active Defense

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Design and Performance Analysis of Emulator for Standard Conformance Test of Active RFID

  • Song, Tae-Seung;Lee, Wang-Sang;Kim, Tae-Yeon;Lyou, Joon
    • ETRI Journal
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    • v.31 no.4
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    • pp.376-386
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    • 2009
  • An active radio frequency identification (RFID) system has the advantages of a long identification distance and a good identification rate, overcoming passive RFID drawbacks. Therefore, interest in the development of active RFID systems has been gradually increasing in areas of harbor logistics and national defense. However, some identification failures between active RFID systems developed under the same standards have been reported, presumably due to a lack of development of accurate evaluation methods and test equipment. We present a realization of the hardware and software of an emulator to evaluate the standard conformance of an active RFID system in a fully anechoic chamber. The performance levels of the designed emulator are analyzed using Matlab/Simulink simulations, and the applicability of the emulator is verified by evaluating the standard conformance of a real active RFID tag. Finally, we propose a new evaluation method by incorporating a self-running test mode environment into the RFID tags to reduce testing time and increase testing accuracy. The application of the suggested method to actual tags improves measurement uncertainty by 0.56 dB over that obtained using existing methods.

Study on Pattern Synthesis of Conformal Phased Array Antenna (컨포멀 위상 배열 안테나의 패턴 합성에 대한 고찰)

  • Park, Dong-Chul;Kwon, Oh-Hyuk;Ryu, Hong-Kyun;Lee, Kyu-Song
    • The Journal of Korean Institute of Electromagnetic Engineering and Science
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    • v.26 no.12
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    • pp.1031-1043
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    • 2015
  • This paper describes the pattern synthesis method of two kinds of conformal array antenna using the Enhanced Adaptive Genetic Algorithm (EAGA). One is the $1{\times}16$ conformal array antenna on a curved cylindrical metallic surface with quadratic function, and the other is the 18-element conformal arrary antenna on a metallic surface obtained by the rotation of a quadratic function curve around the axis. The active element pattern is utilized in the pattern synthesis. Especially for the case of the rotated-type conformal array antenna the transformed active element pattern obtained from the Euler's angle rotation of the active element pattern of the planar concentric array is utilized, which reduces the synthesis time a lot. To verify the validity of the proposed synthesis method the MATLAB results are compared with the MWS results. Furthermore, for the case of $1{\times}16$ conformal array antenna the measured results are compared with the MATLAB synthesized results.

Defense Genes Induced by Pathogens and Abiotic Stresses in Panax ginseng C.A. Meyer

  • Lee, Ok-Ran;Sathiyaraj, Gayathri;Kim, Yu-Jin;In, Jun-Gyo;Kwon, Woo-Seang;Kim, Ju-Han;Yang, Deok-Chun
    • Journal of Ginseng Research
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    • v.35 no.1
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    • pp.1-11
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    • 2011
  • Korean ginseng is a medicinally important perennial herb from the family Araliaceae. It has been cultivated for its highly valued medicinal properties for over 1,000 years in east Asian countries such as China, Korea, and Japan. Due to its longtime cultivation in shady areas, ginseng is frequently exposed to pathogenic infections. Plants protect themselves from microbial pathogens using an array of defense mechanisms, some of which are constitutively active, while others are activated upon pathogen invasion. These induced defense responses, controlled by defense-related genes, require tradeoffs in terms of plant fitness. We hypothesize that ginseng, as with other plants, possesses regulatory mechanisms that coordinate the activation of attacker-specific defenses in order to minimize fitness costs while attaining optimal resistance. Several classes of defense-related genes are induced by infection, wounds, irradiation, and other abiotic stresses. Both salicylates and jasmonates have been shown to cause such responses, although their specific roles and interactions in signaling and development are not fully understood in ginseng. This review summarizes possible defense-related genes in ginseng based on their expression patterns against biotic and abiotic stresses and describes their functional roles.

Study on Developmental Strategy of National Defense & IT Convergence (국방IT융합기술의 발전전략에 관한 연구)

  • Koo, Han Lim;Kim, Seong Min;Rhee, Woo Seop
    • Convergence Security Journal
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    • v.14 no.6_1
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    • pp.99-112
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    • 2014
  • National Defense & IT Convergence is ensuring actual force integration by developing new IT Convergence Technology for the purpose of realizing the concept of Network Centric Warfare. The Ministry of Defense has appointed National Defense & IT Convergence Center of Defense Agency for Technology and Quality as a specialized agency for the National Defense & IT Convergence development, a mission in the creative economy era and has been active in military demand inquiry and prior technology plan with the industrial-academic research institute for discovery of National Defense IT Convergence projects based on the Convergence Center. Further, it is promoting focused on the timely introduction of private IT new technology by operating the project planning team comprised of defense domain specialists and by applying the advanced planning method etc. Accordingly, for the development of National Defense & IT convergence, developmental strategy is urgently required to be utilized effectively after considering theoretically on the national IT Convergence policy enforcement and phenomenon of National Defense & IT Convergence technology and analyzing them comprehensively. This thesis promotes in phases the IT Convergence projects which are identified for the development, improves the efficiency of newly created National Defense & IT Convergence center and suggests training program of IT Convergence personnel related to the defense reforms. With such, it will achieve smart defense in advance and will also contribute largely for the realization of the immediate paradigm shift and of the creative economy.

A Neural Network Aided Kalman Filtering Approach for SINS/RDSS Integrated Navigation

  • Xiao-Feng, He;Xiao-Ping, Hu;Liang-Qing, Lu;Kang-Hua, Tang
    • Proceedings of the Korean Institute of Navigation and Port Research Conference
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    • v.1
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    • pp.491-494
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    • 2006
  • Kalman filtering (KF) is hard to be applied to the SINS (Strap-down Inertial Navigation System)/RDSS (Radio Determination Satellite Service) integrated navigation system directly because the time delay of RDSS positioning in active mode is random. BP (Back-Propagation) Neuron computing as a powerful technology of Artificial Neural Network (ANN), is appropriate to solve nonlinear problems such as the random time delay of RDSS without prior knowledge about the mathematical process involved. The new algorithm betakes a BP neural network (BPNN) and velocity feedback to aid KF in order to overcome the time delay of RDSS positioning. Once the BP neural network was trained and converged, the new approach will work well for SINS/RDSS integrated navigation. Dynamic vehicle experiments were performed to evaluate the performance of the system. The experiment results demonstrate that the horizontal positioning accuracy of the new approach is 40.62 m (1 ${\sigma}$), which is better than velocity-feedback-based KF. The experimental results also show that the horizontal positioning error of the navigation system is almost linear to the positioning interval of RDSS within 5 minutes. The approach and its anti-jamming analysis will be helpful to the applications of SINS/RDSS integrated systems.

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A Biostimulant Preparation of Brown Seaweed Ascophyllum nodosum Suppresses Powdery Mildew of Strawberry

  • Bajpai, Sruti;Shukla, Pushp Sheel;Asiedu, Samuel;Pruski, Kris;Prithiviraj, Balakrishnan
    • The Plant Pathology Journal
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    • v.35 no.5
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    • pp.406-416
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    • 2019
  • Strawberry, an important fruit crop, is susceptible to a large number of pathogens that reduce fruit quality and productivity. In this study, the effect of a biostimulant prepared from Ascophyllum nodosum extract (ANE) (0.1%, 0.2%, and 0.3%) was evaluated on powdery mildew progression under greenhouse and field conditions. In the greenhouse, application of 0.2% ANE showed maximum reduction in powdery mildew progression as compared to the control. Forty-eight hour post-inoculation, foliar spray of 0.2% ANE reduced spore germination by 75%. Strawberry leaves sprayed with ANE showed higher total phenolic and flavonoid content in response to powdery mildew infection. Furthermore, application of ANE elicited defense response in strawberry plants by induction of defense-related enzymes, such as phenylalanine ammonia lyase, polyphenol oxidase, and peroxidase activity. In field conditions, foliar spray of 0.2% ANE showed a reduction of 37.2% of natural incidence of powdery mildew infection as compared to the control. ANE sprayed plant also reduces the severity of powdery mildew infection under natural conditions. These results indicate that application of ANE induces the strawberry plant's active defense against powdery mildew infection by induction of secondary metabolism and regulating the activities of defense-related enzymes.

Competitive Efforts Regarding the South Pacific Islands by South Korea, Japan and China (동아시아 국가들의 태평양 쟁탈전 : 한국, 일본, 중국의 남태평양 도서국가 외교)

  • Park, Young-June
    • Ocean and Polar Research
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    • v.35 no.4
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    • pp.373-381
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    • 2013
  • The Pacific Island Forum that consists of 14 island countries in the South Pacific has long been the focus of keen attention from East Asian countries such as South Korea, Japan and China. The South Pacific area was controlled by Japan right after the First World War. The League of Nations bestowed the right of trusteeship over the region to Japan, one of the victors in the war. However, the U.S. considered the area indispensible for its security interests in the Pacific after victory in the Second World War. With the end of Cold War period, the region again began to gain the competitive attention of Japan, China and Korea. Japan has made efforts to give economic assistance to this region by holding the Japan-Pacific Islands summit every three years. In addition, Japan is promoting a security engagement with this region by dispatching Self Defense Forces with the aim of initiating construction and development projects. In response to Japan's active involvement in the region, China also began to convene a summit meeting with these countries in 2006, making pledges of economic assistance. Furthermore, Chinese civilian companies struck deals of investment with municipal institutions in the region with a view to enhancing China's influence in the region. Japan's and China's active engagement in the region has galvanized South Korea to craft a more effective strategic approach to the region.

Analysis on Heat Dissipation Characteristics of a Tile-Type Digital Transmitter/Receiver Module (적층형 디지털송수신모듈의 방열특성 분석)

  • Yoon, Kichul;Kim, Sangwoon;Heo, Jaehun;Kwak, Nojin;Kim, Chan Hong
    • Journal of the Korea Institute of Military Science and Technology
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    • v.22 no.2
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    • pp.249-254
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    • 2019
  • A Digital Transmitter/Receiver Module(DTRM), which is an essential part in active phased-array radar systems, generates a high heat density, and needs to be properly cooled for stable operation. A tile-type DTRM that is a stacking structure of multi-layer components was modeled with simplification and heat dissipation characteristics of the DTRM model were studied using computational fluid dynamics(CFD) simulations. Most of the heat was dissipated by the heat conduction through the cold plate, but the heat transfer by the forced convection on top of the DTRM also was found to play an important role in the thermal management. Under the given conjugated heat transfer environment, the DTRM was confirmed to secure a stable operating temperature range.

Study on the Compact K-Band Radar for Detecting the Approaching Target above Ground (지상 접근 표적 감지를 위한 초소형 K-대역 레이다 연구)

  • Ha, Jong-Soo;Roh, Jin-Eep;Choi, Jae-Hyun;Lee, Han-Jin;Park, Young-Sik
    • The Journal of Korean Institute of Electromagnetic Engineering and Science
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    • v.28 no.4
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    • pp.309-317
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    • 2017
  • This paper proposes a compact K-band radar applied to a miniature proximity fuze for the active defense system. In this terrestrial environment, it is not easy to detect approaching small targets because the clutter is scattered. In addition, it is difficult to miniaturize the radar for the small proximity fuze while improving the target accuracy of the radar in such environments. To solve these difficulties, this study presents system analysis and design, antenna design, and transceiver and signal processor design of the compact K-band radar. Some test results are presented and the results are analyzed, the validity of the proposed study is examined.

Adenosine derived from Staphylococcus aureus-engulfed macrophages functions as a potent stimulant for the induction of inflammatory cytokines in mast cells

  • Ma, Ying Jie;Kim, Chan-Hee;Ryu, Kyoung-Hwa;Kim, Min-Su;So, Young-In;Lee, Kong-Joo;Garred, Peter;Lee, Bok-Luel
    • BMB Reports
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    • v.44 no.5
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    • pp.335-340
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    • 2011
  • In this study, we attempted to isolate novel mast cell-stimulating molecules from Staphylococcus aureus. Water-soluble extract of S. aureus cell lysate strongly induced human interleukin-8 in human mast cell line-1 and mouse interleukin-6 in mouse bone marrow-derived mast cells. The active molecule was purified to homogeneity through a $C_{18}$ reverse phase HPLC column. By determination of its structure by MALDITOF and $^1H$- and $^{13}C$-NMR, adenosine was revealed to be responsible for the observed cytokine induction activities. Further studies using 8-sulfophenyl theophylline, a selective adenosine receptor blocker, verified that purified adenosine can induce interleukin-8 production via adenosine receptors on mast cells. Moreover, adenosine was purified from S. aureus-engulfed RAW264.7 cells, a murine macrophage cell line, used to induce phagocytosis of S. aureus. These results show a novel view of the source of exogenous adenosine in vivo and provide a mechanistic link between inflammatory disease and bacterial infection.