• Title/Summary/Keyword: Defense response

Search Result 782, Processing Time 0.036 seconds

Identification of Glycine max Genes Expressed in Response to Soybean mosaic virus Infection

  • Jeong, Rae-Dong;Lim, Won-Seok;Kwon, Sang-Wook;Kim, Kook-Hyung
    • The Plant Pathology Journal
    • /
    • v.21 no.1
    • /
    • pp.47-54
    • /
    • 2005
  • Identification of host genes involved in disease progresses and/or defense responses is one of the most critical steps leading to the elucidation of disease resistance mechanisms in plants. Soybean mosaic virus (SMV) is one of the most prevalent pathogen of soybean (Glycine max). Although the soybeans are placed one of many important crops, relatively little is known about defense mechanism. In order to obtain host genes involved in SMV disease progress and host defense especially for virus resistance, two different cloning strategies (DD RT-PCR and Subtractive hybridization) were employed to identify pathogenesis- and defenserelated genes (PRs and DRs) from susceptible (Geumjeong 1) and resistant (Geumjeong 2) cultivars against SMV strain G7H. Using these approaches, we obtained 570 genes that expressed differentially during SMV infection processes. Based upon sequence analyses, differentially expressed host genes were classified into five groups, i.e. metabolism, genetic information processing, environmental information processing, cellular processes and unclassified group. A total of 11 differentially expressed genes including protein kinase, transcription factor, other potential signaling components and resistant-like gene involved in host defense response were selected to further characterize and determine expression profiles of each selected gene. Functional characterization of these genes will likely facilitate the elucidation of defense signal transduction and biological function in SMV-infected soybean plants.

A Change of U.S. Ballistic Missile Defense Strategy (미국 탄도미사일방어 전략의 변화)

  • Park, Tae-Yong
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
    • /
    • 2017.05a
    • /
    • pp.371-372
    • /
    • 2017
  • The United States has built a missile defense system from the Cold War era, but since the end of the Cold War era, there have been many changes in international situation and threats. The forces of power divided between the United States and the Soviet Union have become increasingly threatened by China's willingness to expand its external influence, declaration of strong Russia and North Korea and Iran's nuclear armament and advanced ballistic missile technology. In response to this threat change, the Missile Defense Agency(MDA) has established strategies and policies, but its parent law has not been revised. United States changed to the FY2017 National Defense Authorization Act (FY2017 NDAA) including changed missile defense strategy. In this paper, I check US ballistic missile defense strategies included in the FY2017 NDAA and compare what changes have been made in existing strategies.

  • PDF

A Comparison for the Maturity Level of Defense AI Technology to Support Situation Awareness and Decision Making (상황인식 및 의사결정지원을 위한 국방AI기술의 성숙도 수준비교)

  • Kwon, Hyuk Jin;Joo, Ye Na;Kim, Sung Tae
    • Journal of the Korean Society of Systems Engineering
    • /
    • v.18 no.1
    • /
    • pp.90-98
    • /
    • 2022
  • On February 12, 2019, the U.S. Department of Defense newly established and announced the "Defense AI Strategy" to accelerate the use of artificial intelligence (AI) technology for military purposes. As China and Russia invested heavily in AI for military purposes, the U.S. was concerned that it could eventually lose its advantage in AI technology to China and Russia. In response, China and Russia, which are hostile countries, and especially China, are speeding up the development of new military theories related to the overall construction and operation of the Chinese military based on AI. With the rapid development of AI technology, major advanced countries such as the U.S. and China are actively researching the application of AI technology, but most existing studies do not address the special topic of defense. Fortunately, the "Future Defense 2030 Technology Strategy" classified AI technology fields from a defense perspective and analyzed advanced overseas cases to present a roadmap in detail, but it has limitations in comparing private technology-oriented benchmarking and AI technology's maturity level. Therefore, this study tried to overcome the limitations of the "Future Defense 2030 Technology Strategy" by comparing and analyzing Chinese and U.S. military research cases and evaluating the maturity level of military use of AI technology, not AI technology itself.

Design and Manufacture of Traveling-wave Electro-optic Modulator for X-band LFM Signal Generation (X-대역 LFM 신호생성을 위한 진행파형 전광변조기의 설계 및 제작)

  • Yi, Minwoo;Yoo, Sungjun;Bae, Youngseok;Jang, Sunghoon;Ryoo, Joonhyung;Shin, Jinwoo
    • Journal of the Korea Institute of Military Science and Technology
    • /
    • v.24 no.6
    • /
    • pp.610-618
    • /
    • 2021
  • In this paper, a photonic-based microwave system technology is described, and a traveling-wave electro-optic modulator is designed and manufactured as a key component. The fabricated modulator is composed of a metal diffusion waveguide for optical transmission and a planar waveguide electrode on lithium niobate substrate for microwave transmission. The electro-optic response bandwidth of I and Q channels in a fabricated dual parallel Mach-Zehnder modulator were measured for 27.67 and 28.11 GHz, respectively. Photonic four times up-converted X-band frequency and linear frequency modulated signal were confirmed using the fabricated electro-optic modulator by S-band input signal. The confirmed broadband signal can be applied to a microwave system for surveillance and high-resolution ISAR imaging.

Expression of Perforin Gene for Early Development of Nephrons in Olive Flounder (Paralichthys olivaceus)

  • Yang, Hyun;Lee, Young Mee;Lee, Jeong-Ho;Noh, Jae Koo;Kim, Hyun Chul;Park, Choul-Ji;Park, Jong-Won;Hwang, In Joon;Kim, Sung Yeon
    • Development and Reproduction
    • /
    • v.17 no.4
    • /
    • pp.321-327
    • /
    • 2013
  • The innate immune system is the only defense weapon that invertebrates have, and it is the fundamental defense mechanism for fish. The innate immune response is important in newly hatched flounders because it is closely involved in the initial feeding phase, which is why it is essential for survival during the juvenile period. The expression analysis of genes involved in the innate immune response in the olive flounder (Paralichthys olivaceus) in the days after hatching is incomplete. Therefore, we have begun to examine the expression patterns of genes specifically induced during the development of the innate immune system in newly hatched flounders. Microscopic observation showed that pronephron formation corresponded with the expression of perforin-encoding gene. These results suggest that perforin plays a vital role in the innate immunity of the kidney during developmental stages. Perforin expression was strong at the start of the development of the innate immune response, and continued throughout all the development stages. Our findings have important implications with respect to perforin's biological role and the evolution of the first defense mechanisms in olive flounder. Further studies are required to elucidate the perforin-mediated innate immunity response and to decipher the functional role of perforin in developmental stages.

A Study on Acoustic and Vibratory Response of a MEMS Resonant Accelerometer (공진형 MEMS 가속도계의 음향가진 반응특성 연구)

  • Lee, Sang Woo;Lee, Hyung Sub;Yu, Myeong-Jong;Kim, Do Hyung
    • The Transactions of The Korean Institute of Electrical Engineers
    • /
    • v.64 no.9
    • /
    • pp.1330-1336
    • /
    • 2015
  • It is necessary to study on acoustic and vibratory response of a MEMS resonant accelerometer before applying to military applications. In this paper, we analyze why the resonant accelerometer reacts to an acoustic wave and a high frequency vibration. And we describe experimental results on acoustic and vibratory response of the accelerometer. The accelerometer consists of a proof mass and a dual ended tuning fork. It is a differential resonant accelerometer with arranging a pair of accelerometers. The mode shape was analyzed to find out the input mode frequency by using a FEM simulation. Some experiments regarding the acoustic noise was carried out by using a tweeter and a microphone in the anechoic room. Results showed that the accelerometer reacted to the acoustic wave and vibration which had the input mode frequency as we had expected. We showed experimentally not only that the susceptibility of the accelerometer to an acoustic wave was 70 dB but also that the effectiveness of applying an acoustic absorber and a metal case was 20 dB, respectively. Also, we could minimize the vibratory response property of the accelerometer by installing a IMU with a silicone rubber mount pad.

Explicating morphophysiological and biochemical responses of wheat grown under acidic medium: Insight into to the antioxidant defense and glyoxalase systems

  • Bhuyan, MHM Borhannuddin;Hasanuzzaman, Mirza;Al Mahmud, Jubayer;Hossain, Md. Shahdat;Alam, Mazhar Ul;Fujita, Masayuki
    • Proceedings of the Korean Society of Crop Science Conference
    • /
    • 2017.06a
    • /
    • pp.236-236
    • /
    • 2017
  • Low soil pH causes from $H^+$ rhizotoxicity results in nutrients unavailability in the growing media, inhibits plant growth, development and reduces crop yields. The present study was carried out to reveal morpholophysiological and biochemical responses of wheat (Triticum aestivum L.) to acidity stress. Four wheat varieties viz. BARI Wheat-21, BARI Wheat-25, BARI Wheat-26 and BARI Wheat-30 were used in the study. Eight-day-old seedlings were exposed to different pH levels (3.5, 4.5, 5.5 and 6.5) of growing media. Acidity stress at any level reduced biomass, water, and chlorophyll contents in all the varieties; whereas BARI Wheat-26 showed the least damage. $H^+$ rhizotoxicity also caused oxidative stress through excess production of reactive oxygen species and methylglyoxal which increase lipid peroxidation in all the varieties but the lowest oxidative damage was observed in BARI Wheat-26 due to better performance of the antioxidant defense and glyoxalase systems. Considering the growth, physiological and biochemical attributes BARI Wheat-26 may be considered as acidity stress tolerant, among the variety examined.

  • PDF

Analysis of Boundary Layer in Solid Rocket Nozzle and Numerical Analysis of Thermal Response of Carbon/Phenolic using Finite Difference Method (고체 로켓 노즐의 경계층 해석과 유한차분법을 이용한 탄소/페놀릭의 열반응 해석 연구)

  • Seo, Sang Kyu;Hahm, Hee Cheol;Kang, Yoon Goo
    • Journal of the Korean Society of Propulsion Engineers
    • /
    • v.22 no.1
    • /
    • pp.36-44
    • /
    • 2018
  • The thermal response of carbon/phenolic used in a solid rocket nozzle liner was analyzed. In this paper, the numerical analysis of the thermal response of carbon/phenolic consists of (1) the integration equation of the boundary layer to obtain the convective heat transfer coefficient of the combustion gas on the rocket nozzle wall and (2) 1-D finite difference method for heat conduction of carbon/phenolic to calculate the ablation, char, and temperature. The calculated result was compared with the result of a blast-tube-type test motor. It is found that the calculated result shows good agreement with the thermal response of the test motor, except at the vicinity of the throat insert.

Analysis on the transient response of Polyphase DFT filter banks in the frequency hopping communication satellite transponder (주파수 도약 통신위성 중계기의 다상 DFT 필터뱅크 과도기 응답 분석)

  • Lee, Daeil;Joo, Jaikwan
    • Journal of the Korean Society for Aeronautical & Space Sciences
    • /
    • v.42 no.7
    • /
    • pp.610-615
    • /
    • 2014
  • Filterbanks have been widely used in the field of multi-channel signal processing for their simple efficient implementation architectures. Especially, the polyphase DFT(Discrete Fourier Transform) filterbank is the most preferred filterbank for the uniform spaced multi-channel processing due to its simplicity. In frequency hopped communication systems, however, the use of the polyphase DFT filterbank is limited due to its undesirable transient response from hop-to-hop transitions. In this paper, the transient response of polyphase DFT filterbanks in the hop-to-hop transition was analyzed, and the efficient methods to overcome such a problem was proposed. Simulation results showed that the proposed schemes could resolve this issue efficiently.

Thermal Response Modeling of Thermal Protection Materials and Application Trends of Commercial Codes for Flow-Thermal-Structural Analysis (내열재의 열반응 모델링 및 유동-열-구조해석의 상용코드 적용 동향)

  • Hwang, Ki-Young;Bae, Ji-Yeul
    • Journal of the Korean Society of Propulsion Engineers
    • /
    • v.23 no.6
    • /
    • pp.59-71
    • /
    • 2019
  • The numerical analysis of ablative thermal protection systems (TPS) for solid rockets has been carried out with various in-house codes since the 1960s. However, the application scope of commercial codes has been expanded by adding subroutines and user-defined functions (UDF) to codes such as Fluent, Marc, and ABAQUS. In the past, the flow, thermal response and structural analysis of TPS have been performed using separate approaches. Recently, research has been conducted to interrelate them. In this paper, the thermal response characteristics of thermal protection materials, the in-house codes for thermal response analysis, and the research trends of flow-thermal-structure analysis of TPS using commercial codes were reviewed.