• Title/Summary/Keyword: Defense Field

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A Study on Prediction Technique for Underwater Electric Field Signature Characteristic using Dipole Modelling Method (다이폴 모델링 기법을 이용한 수중 전기장 신호 특성 예측 기법 연구)

  • Yang, Chang-Seob;Chung, Hyun-Ju;Lee, Jong-Ju;Jeon, Jae-Jin
    • Journal of the Korean Magnetics Society
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    • v.18 no.6
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    • pp.221-224
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    • 2008
  • This paper describes the equivalent dipole modeling method utilizing a singular value decomposition technique from analysis data by the FNREMUS Detailled Modeller software based on BEM which can predict the underwater electric field signal due to a galvanic corrosion phenomenon on a naval vessel. The proposed dipole modeling method was successfully verified in good agreement with predicted BEM data at 30 m depths through the comparison of average differences. The proposed dipole modelling method can be effectively used in the prediction and analysis of static electric field signature distributions generated from a naval vessel at any different depths.

A Study on the Electric Field Source Modeling of Naval Vessel Utilizing Material Sensitivity (매질 민감도를 이용한 함정 전기장 신호원 모델링에 관한 연구)

  • Chung, Hyun-Ju;Yang, Chang-Seob;Jeon, Jae-Jin;Jung, Gi-Woo;Kim, Dong-Hun
    • Proceedings of the KIEE Conference
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    • 2009.07a
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    • pp.658_659
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    • 2009
  • This paper deals with the numerical implementation of the material sensitivity analysis, which is used to efficiently determine an optimal electric current distribution on a ship hull by corrosion of ship. A material sensitivity formula for the forward problem formulated in terms of the equivalent current method is analytically derived. Then, the components of the adjoint system including the electric pseudo-source are thoroughly investigated in order to obtain the first-order gradient information of an objective function with respect to the electric current. The purposed method has been successfully applied to a model ship and the predicted result on the underwater electric field due to corrosion of ship have been compared to that computed by FNREMUS software.

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Rapid, Simultaneous Detection of Various Biological Toxin Genes Using Multiplex Reverse Transcription Loop-Mediated Isothermal Amplification(RT-LAMP) (다중 역전사-루프매개등온증폭법(RT-LAMP)를 이용한 생물 독소 유전자 신속 진단법)

  • Seungho Lee;Chanho Chung;Sehun Gu;Jungeun Kim;Hyeongseok Yun;Daesang Lee;Gyeunghaeng Hur;Donghyun Song
    • Journal of the Korea Institute of Military Science and Technology
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    • v.27 no.4
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    • pp.516-527
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    • 2024
  • Rapid, early, accurate detection and identification of the various pathogenic agents associated with the development of biological weapons is critical in preventing loss of life and limiting the impact of these organisms when used against civilian or military targets. The aim of this study was to produce a system for the simple, rapid, accurate and simultaneous detection and identification of Ricin, Botulinum toxin B and Staphylococcal enterotoxin B as a proof of principle for developing field appropriate reverse transcription loop-mediated isothermal amplification systems for the accurate identification of potential biological threats. These systems were designed to facilitate the identification of potential threats even in remote or resource-limited locations.

A Study of Reliability of Guided Missile(◯◯) using Probit Analysis (Probit 분석을 이용한 ◯◯유도탄 신뢰도 분석 및 활용방안)

  • Hong, SeokJin;Jung, SangHoon
    • Journal of Korean Society for Quality Management
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    • v.44 no.3
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    • pp.553-564
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    • 2016
  • Purpose: The purpose of this study was to propose useful suggestions by analyzing reliability of guided missile using field data in Military industry. Methods: The collected data from Defense industry company and the military were analyzed using probit analysis which is non-linear model because field data contain binary variable. Results: The results of this study are as follows; It was found that the effect of time was significant. It takes about 12.4 years when 10st percentile of guided missiles are not working and it takes about 18.6 years when 50st percentile of guided missiles are not working. It was found that period between 10years to 15years comes less than reliability 0.0. Conclusion: Periodical check needs to extend from 4 year to 10 year partially. Early LOT need to check per 4 year and follow-up LOT extend the period of check to 10 year by reflecting the result of reliability.

Radar Countermeasure and Effect Analysis for the Pull-Off Deceptive Jamming Signal (Pull-Off 기만 재밍 신호에 대한 레이다 대응기법 및 효과 분석)

  • Jang, Sunghoon;Kim, Seonjoo
    • Journal of the Korea Institute of Military Science and Technology
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    • v.23 no.3
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    • pp.221-228
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    • 2020
  • This paper presents the radar counter jamming algorithm and ground far-field test results for the pull-off deceptive jamming signals like RGPO(Range Gate Pull Off) and VGPO(Velocity Gate Pull Off). We designed the radar counter jamming algorithm according to the characteristics of the deceptive jamming signals. This algorithm is validated by simulation before ground far-field test. The existing X-band AESA radar demonstrator was used to test the proposed algorithm. The proposed algorithm was applied to the radar processor software. The deceptive jamming signals generated using the commercial jamming signal generator. We performed the repeated ground far-field test with the test scenario. Test results show that the proposed counter deceptive jamming algorithm works in the real radar system.

A Study on the Field of View of the Remote FTIR Chemical Imaging Detection System (원거리 화학영상탐지시스템의 시야각에 대한 연구)

  • Lee, Jong-Min;Kang, Young-Il;Kim, Ju-Hyun
    • Journal of the Korea Institute of Military Science and Technology
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    • v.17 no.1
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    • pp.122-128
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    • 2014
  • Remote fourier transform infrared(FTIR) chemical imaging detection system allows detection and identification of gases in the atmosphere from long distances. In this paper, the appropriate field of view(FOV) of the FTIR imaging system was examined and the main performance of the system for the interferometer was described. For the determination of the FOV, simulations of gas dispersion range were performed with the NBC reporting and modeling software(NBC-RAMS) developed by ADD. As a result, minimum 192 mrad of FOV was required for the remote FTIR imaging system to visualize chemical warfare agents dispersed in several hundred meters. At the same time, 0.75 mrad of instantaneous field of view(IFOV) for a linear interferometer proper to take a FOV for the chemical agent imaging.

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.

Design of Decentralized Guidance Algorithm for Swarm Flight of Fixed-Wing Unmanned Aerial Vehicles (고정익 소형무인기 군집비행을 위한 분산형 유도 알고리듬 설계)

  • Jeong, Junho;Myung, Hyunsam;Kim, Dowan;Lim, Heungsik
    • Journal of the Korean Society for Aeronautical & Space Sciences
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    • v.49 no.12
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    • pp.981-988
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    • 2021
  • This paper presents a decentralized guidance algorithm for swarm flight of fixed-wing UAVs (Unmanned Aerial Vehicles). Considering swarm flight missions, we assume four representative swarm tasks: gathering, loitering, waypoint/path following, and individual task. Those tasks require several distinct maneuvers such as path following, flocking, and collision avoidance. In order to deal with the required maneuvers, this paper proposes an integrated guidance algorithm based on vector field, augmented Cucker-Smale model, and potential field methods. Integrated guidance command is synthesized with heuristic weights designed for each guidance method. The proposed algorithm is verified through flight tests using up to 19 small fixed-wing UAVs.

Development of Multi-rod Type Ag-AgCl Electrodes for an Underwater Electric Field Sensor (수중 전기장 센서용 다중 막대형 은-염화은 전극 개발)

  • Lee, Sangkyu;Yang, Chang-Seob;Chung, Hyun-Ju
    • Journal of Sensor Science and Technology
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    • v.31 no.1
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    • pp.45-50
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    • 2022
  • Multi-rod type Ag-AgCl electrodes have been developed for use in underwater electric field sensors. The developed cylindrical electrode had a diameter of 50 mm and a height of 130 mm. The electrode had five Ag-AgCl rods with a diameter of 2 mm and a height of 80 mm to enlarge the reaction surface area. Each Ag-AgCl rod was fabricated under the same conditions as the usual anodizing method in an electrolyte. The two developed electrodes were placed in the center of a 500-mm long, 400-mm wide, and 300-mm high acrylic tank filled with artificial seawater, at an interval of 100 mm, to evaluate their characteristics as uniaxial underwater electric field sensors. The underwater external electric field was generated using titanium plate electrodes installed at both ends of the tank. The noise level at 1 Hz of the developed electrode was approximately 3.7 nV/√Hz. The reception of the underwater electric field signal using the developed electrode was linear, within an error of approximately 0.6 %, in the range of 1-10000 ㎶/m at 1 Hz. In addition, its frequency response was flat within an error of 1.1 % in the range of 1-1000 Hz at 10000 ㎶/m.

A suggestion for reforming defense education system and army college education program in the next decade (국방교육체계 정립과 육군대학 군사학 교육체계 발전방향)

  • Choe, In-Su
    • Journal of National Security and Military Science
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    • s.3
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    • pp.35-72
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    • 2005
  • The purpose of this paper is to recommend the Ministry of Defense(MOD) for revolutionizing the current defense education system. As an instructor and an education planning officer of the ROK Army College, for last dozen months, the author has been embarrassed whenever tried to figure out what would be the role, functions, and educational goals of the college. In a nutshell, there has not been any general guidance for educating field grade officers. This unbelievable defect mainly comes from the absence of a responsible organization in the MOD. Even though it has the education branch under the department of personnel affairs, it doesn't have capabilities to design and implement the consistent and valuable education policy. Therefore, the development of defense education should begin with reinforcing the organization and functions of the MOD education branch. We need more experts on education( i.e. Ph.Ds of Education) and experienced specialties on defense education so that we could develop the overall guidance for military professional education. In addition, we need to enact the "defense or military education act" in a tentative name. This will ensure the legitimacy and continuity of defense education guidance initiated by the MOD. In a conclusion, it is senseless to think the blueprint for the Army College out until the preconditions mentioned above are matured. We must begin with rectifying the higher educational system.

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