• Title/Summary/Keyword: air defense

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Numerical Investigation of Scattering from a Surface Dielectric Barrier Discharge Actuator under Atmospheric Pressure

  • Kim, Yuna;Kim, Sangin;Kim, Doo-Soo;Oh, Il-Young;Yook, Jong-Gwan
    • Journal of electromagnetic engineering and science
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    • v.18 no.1
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    • pp.52-57
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    • 2018
  • Surface dielectric barrier discharge (SDBD), which is widely used to control turbulence in aerodynamics, has a significant effect on the radar cross-section (RCS). A four-way linearly synthesized SDBD air plasma actuator is designed to bolster the plasma effects on electromagnetic waves. The diffraction angle is calculated to predict the RCS because of the periodic structure of staggered electrodes. The simplified plasma modeling is utilized to calculate the inhomogeneous surface plasma distribution. Monostatic RCS shows the diffraction in the plane perpendicular to the electrode array and the notable distortion by plasma. In comparison, the overall pattern is maintained in the parallel plane with minor plasma effects. The trends also appear in the bistatic RCS, which has a significant difference in the observation plane perpendicular to the electrodes. The peaks by Bragg's diffraction are shown, and the RCS is reduced by 10 dB in a certain range by the plasma effect. The diffraction caused by the actuator and the inhomogeneous air plasma should be considered in designing an SDBD actuator for a wide range of application.

An Investigation into Improving the Quality of Modern Weapon System Software Products: a Case Study (현대 무기체계 소프트웨어 개발 사례 분석을 통한 품질개선 방안에 대한 연구)

  • Choi, Taeyun Paul;Lee, Hyo-Jin
    • Journal of the Korean Society of Systems Engineering
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    • v.8 no.2
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    • pp.19-25
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    • 2012
  • As modern weapon systems have evolved into embedded software systems, the capability to develop, install, and maintain high-quality software products is becoming increasingly valuable in today's competitive aerospace and defense industry. It is desirable, especially for government-contracted projects whose end-users are military personnel, that specific types of software quality elements are assured early during product development; namely, functionality and usability. Motivated by this need to approach improving software quality from a user's perspective, this paper presents a case study that analyzes system-level software integration testing results for a weapon system indigenously developed in the Republic of Korea. Quantitative data, such as software defect ratios and configuration change rates, are computed to observe meaningful trends with respect to functionality - represented by tests designed to verify the system's electrical signal interfaces - and usability, which is evaluated in terms of how often the initial human-computer interface had to be re-designed. Insights gained from these exercises are subsequently presented as a set of "lessons learned" to take into account when developing new software items for complex weapon systems.

Two Attribute-based Broadcast Encryption Algorithms based on the Binary Tree (이진트리 기반의 속성기반 암호전송 알고리즘)

  • Lee, Moon Sik;Kim, HongTae;Hong, Jeoung Dae
    • Journal of the Korea Institute of Military Science and Technology
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    • v.17 no.3
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    • pp.358-363
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    • 2014
  • In this paper, we present two constructions of the attribute-based broadcast encryption(ABBE) algorithm. Attribute-based encryption(ABE) algorithm enables an access control mechanism over encrypted data by specifying access policies among private keys and ciphertexts. ABBE algorithm can be used to construct ABE algorithm with revocation mechanism. Revocation has a useful property that revocation can be done without affecting any non-revoked uers. The main difference between our algorithm and the classical ones derived from the complete subtree paradigm which is apt for military hierarchy. Our algorithm improve the efficiency from the previously best ABBE algorithm, in particular, our algorithm allows one to select or revoke users by sending ciphertext of constant size with respect to the number of attributes and by storing logarithm secret key size of the number of users. Therefore, our algorithm can be an option to applications where computation cost is a top priority and can be applied to military technologies in the near future.

"Peaceful Uses" of Outer Space and Japan' s Space Policy

  • Takai, Susumu
    • The Korean Journal of Air & Space Law and Policy
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    • no.spc
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    • pp.247-270
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    • 2007
  • Space development and utilization must be conducted within a framework of "peaceful uses" principle under Space Treaty. Japan ratified the treaty in 1967, and interpreted "peaceful uses" as "non-military uses" then. A ghost of "peaceful uses" principle has been hung over Japan up to the moment. Japan's space development and utilization has been conducted with genuine academic interest, and therefore Japan did not introduce space infrastructures to national security policy and did not facilitate growth of space industry. When the Cold War ended, Northeast Asian security environment makes Japan difficult to maintain an interpretation as "non-military uses". Besides the change of external security environment, the domestic industry situation and a series of rocket launching failure needed reexamination of Japan's space policy. Japan is gradually changing its space policy, and introducing space infrastructure in a national security policy under a "generalization" theory that gave a broad interpretation of "peaceful uses" principle. Council for Science and Technology Policy (CSTP) adopted a basic strategy of Japan's space policy in 2004. Since then, a long-term report of Japan Aerospace Exploration Agency (JAXA), an investigation report of Society of Japanese Aerospace Companies (SJAC) and a proposal of Japan Business Federation (JSF) were followed. Japan will promote space development and utilization in national security policy with a "strictly defensive defense" strategy and "non-aggressive uses"principle for protection of life and property of Japanese people and stabilization of East Asian countries.

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The Study on the Methodology for Naval Ship(Craft Air Cushion) Vulnerability Analysis (함정(공기부양정) 취약성 분석방법 연구)

  • Choi, Bong-Wan;Lee, Chan-Sun
    • Journal of the Korea Institute of Military Science and Technology
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    • v.13 no.6
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    • pp.1106-1112
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    • 2010
  • One of the considerations in weapon systems procurement is the objective of maximizing the current force. Also, offensive effects, rather than defense are valued in weapons system development and procurement. Especially, the survivability of a naval ship is equally important as the offensive effect of onboard weapons. In case of naval ships, development of attack tactics and research regarding damage minimization must be conducted through live fire exercise against actual targets in order to minimize damage from the enemy. However, it is difficult to conduct such adequate measures due to realistic limitations such as time and budget in order to verify and calculate a weapon system's attack and damage effects along with the lack of practical studies in this subject despite numerous interests. Research are being conducted utilizing M&S to estimate attack effects and study damages due to such reason, but the lack of authoritative data and development ability are limiting calculation of reliable results. Therefore, this study will propose a measure to increase survivability of a weapon system(ship/vessel) utilizing research of vulnerability from enemy attacks analysis method against a naval ship(Craft Air Cushion).

Captive Flight Test System Configuration and Verification for Multi-mode Guidance Missile System (복합유도방식이 적용된 유도탄의 탑재비행시험(CFT) 시스템 구성 및 검증)

  • Park, Inchul;Heo, Wonyoung;Lee, Yongho;Jeong, Seyoung
    • Journal of the Korea Institute of Military Science and Technology
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    • v.19 no.5
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    • pp.606-612
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    • 2016
  • A Captive Flight Test(CFT) is used to verify the performance of missile component such as seeker and guiding algorithm of missile. Recently most of surface to air missile adapts multi-mode guidance method which include command guidance and active/passive guidance. A CFT system for missile system adapting multi-mode guidance method consists of pod equipment, command transmitting system and measuring system. In this paper, we proposed CFT system and testing method for missile which adapt multi-mode guidance, and system integration procedure by using distributed missile system integration method and procedure. The proposed CFT system and system integration method was applied to CFT of surface to air missile, and brought successful result.

An Experimental Study on Multi-Injected Artificial Supercavitation (다중 분사 인공 초월공동에 대한 실험 연구)

  • Ahn, Byoung-Kwon;Kim, Ki-Seong;Jeong, So-Won;Yoon, Hyun-Gull
    • Journal of the Society of Naval Architects of Korea
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    • v.58 no.1
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    • pp.24-31
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    • 2021
  • In this study, we present experimental observations of artificial supercavitation generated by the injection of compressed air at multiple locations on the body. Experiments were conducted at a cavitation tunnel equipped with a special facility to remove injected air before returning to the test section. Artificial supercavitation, which is generated at a relatively low speed compared to natural supercavitation, is formed asymmetrically on the axis of the body due to the buoyancy effect. In order to accelerate the development of the supercavity and increase the area covering the body, an experimental device capable of additional injection from the body was designed and its performance was evaluated through the model test. The shapes of the supercavity generated by multi-injections of different combinations according to different flow speeds were analyzed using high-speed shadow images. The results show that multiple injections at suitable locations can effectively increase the length of the supercavity and consequently improve propulsion efficiency.

Drug distribution management system based on IoT

  • Liu, Zeliang;Zhang, Chunmei;Peng, Hui;Xu, Qin;Gao, Yubao
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.16 no.2
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    • pp.424-444
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    • 2022
  • In hospitals and pharmacies, the distribution of medicines is an important part. Any mistakes, misses, fake medicines and expired medicines can cause medical accidents. With the widespread application of the Internet of Things technology (IoT), traditional drug distribution methods need to be upgraded. This article proposes a drug distribution management scheme based on the Internet of Things technology. In the production of drugs, a flexible RFID tag was printed on the packaging box, which stored a series of information such as drug name, dosage, raw materials, efficacy, production date, expiration date, and manufacturer. The use of a drug distribution management system combined with RFID readers can identify drug information and effectively prevent the occurrence of erroneous, missed, counterfeit, and expired drugs. It can also improve management efficiency, reduce management costs, and control management risks. Through the circuit design and software system development, the test results show that this solution is effective and feasible, the proposed method can achieve the expected results.

Case Study Building a Vertiport for UAM Commercialization: Based on the Demonstration in Pontoise-Cormeiles, France (UAM 상용화를 위한 버티포트 구축 사례 연구: 프랑스 퐁투와즈 실증사례를 중심으로)

  • Joomin Kim
    • Journal of the Korean Society of Industry Convergence
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    • v.27 no.1
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    • pp.77-86
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    • 2024
  • Urban Air Mobility (UAM) is considered the future of transportation, offering solutions to urban challenges and reducing environmental issues through the use of electric power and leveraging the sky as a new transportation corridor. UAM has diverse applications, including passenger and goods transportation, emergency rescue operations, patient transfers, and urban tourism. Furthermore, it is poised to revolutionize the transportation landscape, impacting existing infrastructures such as roads and parking lots, along with autonomous vehicles. The UAM industry is anticipated to exert a significant impact on various sectors, including airframe manufacturing, the development of new materials (e.g., fuel cells and batteries), and even the defense industry, resulting in substantial economic benefits. Consequently, conducting proactive research and setting industry standards for UAM takeoff and landing infrastructure is crucial for securing market leadership. In this regard, the case of Pontoise-Cormeiles, France, stands out as it achieved the world's inaugural successful demonstration of a vertiport before the 2024 Olympics. This achievement has significant implications for our preparations for the commercialization of UAMs. Thus, a detailed review of the French vertiport construction case in this study will serve as a foundation for guiding the planning and operation of UAMs in South Korea, particularly in anticipation of upcoming demonstration tests.

Research on Cyber Kill Chain Models for Offensive Cyber Operations (공세적 사이버 작전을 위한 사이버 킬체인 모델 연구)

  • Seong Bae Jo;Wan Ju Kim;Jae Sung Lim
    • Convergence Security Journal
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    • v.23 no.4
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    • pp.71-80
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    • 2023
  • Cyberspace has emerged as the fifth domain of warfare, alongside land, sea, air, and space. It has become a crucial focus for offensive and defensive military operations. Governments worldwide have demonstrated their intent to engage in offensive cyber operations within this domain. This paper proposes an innovative offensive cyber kill chain model that integrates the existing defensive strategy, the cyber kill chain model, with the joint air tasking order (ATO) mission execution cycle and joint target processing procedure. By combining physical and cyber operations within a joint framework, this model aims to enhance national cyber operations capabilities at a strategic level. The integration of these elements seeks to address the evolving challenges in cyberspace and contribute to more effective jointness in conducting cyber operations.