• Title/Summary/Keyword: national defense

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A Multi-Dimensional Node Pairing Scheme for NOMA in Underwater Acoustic Sensor Networks (수중 음향 센서 네트워크에서 비직교 다중 접속을 위한 다차원 노드 페어링 기법)

  • Cheon, Jinyong;Cho, Ho-Shin
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.22 no.6
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    • pp.1-10
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    • 2021
  • The interest in underwater acoustic sensor networks (UWASNs), along with the rapid development of underwater industries, has increased. To operate UWASNs efficiently, it is important to adopt well-designed medium access control (MAC) protocols that prevent collisions and allow the sharing of resources between nodes efficiently. On the other hand, underwater channels suffer from a narrow bandwidth, long propagation delay, and low data rate, so existing terrestrial node pairing schemes for non orthogonal multiple access (NOMA) cannot be applied directly to underwater environments. Therefore, a multi-dimensional node pairing scheme is proposed to consider the unique underwater channel in UWASNs. Conventional NOMA schemes have considered the channel quality only in node pairing. Unlike previous schemes, the proposed scheme considers the channel gain and many other features, such as node fairness, traffic load, and the age of data packets to find the best node-pair. In addition, the sender employs a list of candidates for node-pairs rather than path loss to reduce the computational complexity. The simulation results showed that the proposed scheme outperforms the conventional scheme by considering the fairness factor with 23.8% increases in throughput, 28% decreases in latency, and 5.7% improvements in fairness at best.

A study on Deep Operations Effect Analysis for Realization of Simultaneous Offense-Defence Integrated Operations (공방동시통합작전 구현을 위한 종심작전 효과분석 연구)

  • Cho, Jung Keun;Yoo, Byung Joo;Han, Do Heon
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.22 no.6
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    • pp.116-126
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    • 2021
  • Ground Component Command (GCC) has been developing operational planning and execution systems to implement "Decisive Integrated Operations", which is the concept of ground operations execution, and achieved remarkable results. In particular, "Simultaneous Offense-Defense Integrated Operations" is developed mainly to neutralize enemies in deep areas and develop favorable conditions for the allies early by simultaneously attacking and defending from the beginning of the war. On the other hand, it is limited to providing scientific and reasonable support for the commander's decision-making process because analyzing the effects of the deep operation with existing M&S systems is impossible. This study developed a model for analyzing the effects of deep operations that can be used in the KJCCS. Previous research was conducted on the effects of surveillance, physical strike, and non-physical strike, which are components of deep operations to find the characteristics and limitations and suggest a research direction. A methodology for analyzing the effects of deep operations reflecting the interactions of components using data was then developed by the GCC, and input data for each field was calculated through combat experiments and a literature review. Finally, the Deep operations Effect CAlculating Model(DECAM) was developed and distributed to the GCC and Corps battle staff during the ROK-US Combined Exercise. Through this study, the effectiveness of the methodology and the developed model were confirmed and contribute to the development of the GCC and Corps' abilities to perform deep operations.

Dazaihu Diplomacy Between United Silla and Japan (통일기 신라와 일본의 대재부외교(大宰府外交)와 그 의미)

  • Cho, lee ok
    • (The)Study of the Eastern Classic
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    • no.73
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    • pp.91-117
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    • 2018
  • In the tribute system controlling international relations of pre-modern East Asia, conciliation diplomacy between royal authorities was a principle of diplomatic relations among each nation. Therefore, capitals where royal authorities really existed were political centers and diplomatic stages at the same time. Notably, diplomatic relations between United Silla and Japan were maintained dually by conciliation diplomacy between royal authorities and practical diplomacy through Dazaihu located in Tsukushi. Tsukushi located at the northwestern tip of Kyushu was a gateway to foreign nations and stronghold in terms of national defense. Amidst an East Asian war named Baek River Battle in 663, the royal court of Daehwa established Dazaihu here because it was necessary for diplomatic and military responses. Dazaihu established as part of diplomatic negotiation not only took diplomatic functions as an official residence since the latter half of the 7thcentury. and but also was used as a stage of official diplomacy between Silla and Japan. Diplomatic negotiation between Silla and Japan through Dazaihu was made in practical methods and such a situation could be confirmed through diplomatic documents exchanged between Silla and Dazaihu in the middle of the 8thcentury. At that time, protocols became an importan tissue.

Adaptive Beamwidth Control Technique for Low-orbit Satellites for QoS Performance improvement based on Next Generation Military Mobile Satellite Networks (차세대 군 모바일 위성 네트워크 QoS 성능 향상을 위한 저궤도 위성 빔폭 적응적 제어 기법)

  • Jang, Dae-Hee;Hwang, Yoon-Ha;Chung, Jong-Moon
    • Journal of Internet Computing and Services
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    • v.21 no.6
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    • pp.1-12
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    • 2020
  • Low-Orbit satellite mobile networks can provide services through miniaturized terminals with low transmission power, which can be used as reliable means of communication in the national public disaster network and defense sector. However, the high traffic environment in the emergency preparedness situation increases the new call blocking probability and the handover failure probability of the satellite network, and the increase of the handover failure probability affects the QoS because low orbit satellites move in orbit at a very high speed. Among the channel allocation methods of satellite communication, the FCA shows relatively better performance in a high traffic environment than DCA and is suitable for emergency preparedness situations, but in order to optimize QoS when traffic increases, the new call blocking and the handover failure must be minimized. In this paper, we propose LEO-DBC (LEO satellite dynamic beam width control) technique, which improves QoS by adaptive adjustment of beam width of low-orbit satellites and call time of terminals by improving FCA-QH method. Through the LEO-DBC technique, it is expected that the QoS of the mobile satellite communication network can be optimally maintained in high traffic environments in emergency preparedness situations.

A Study on Spatial Distribution of Villages in Border Region according to Change in Civilian Control Line (민간인통제선 변화에 따른 접경지역 마을의 공간적 분포에 관한 연구)

  • JEONG, Haeyong
    • Journal of the Korean Association of Geographic Information Studies
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    • v.24 no.2
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    • pp.91-101
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    • 2021
  • This study attempted to conduct the study from a macro perspective more specifically through the temporal and spatial analysis of Minbuk villages according to a change in a Civilian Control Line, such as a social and spatial distribution and a change of the existing Minbuk villages. To this end, this study conducted the spatial analysis for the change in the Minbuk villages according to the adjustment of the Civilian Control Line in time series by using a map of the Armistice Agreement Vol. 2, Google Earth, a digital cadastral map, an administrative district map, and the like are used as spatial data, and summarizing and constructing, as attribute data, a statistical yearbook, Ministry of Defense and Cheorwon-Gun notification data, a Land Use Regulation Information System, and cadastral map attribute information. After the enactment of the Military Facility Protection Act, the analysis was performed on a 20-year basis based on the 1976 statistical yearbook of which the Civilian Control Line was drawn. As a result, the total area of the Civilian Control Zone in Cheorwon from 1975 to 2015 decreased by 105.8 km2, and 9 of 14 Minbuk villages were released and only 6 villages existed. The unoccupied villages were analyzed as 14 villages, 10 fewer than the existing surveyed or statistical villages. The movement of the Civilian Control Line to the north may disappear the unique characteristics of the Minbuk villages but should be done carefully as it is closely related to the lives of the current residents, and policies should be established in terms of sustainable development and conservation of the villages. This study is significant in conducting the temporal and spatial analysis, which is the basis of the Minbuk regions and the Minbuk villages, and may be used as basic data necessary for subsequent analysis study.

Effects of Management Support for Health and Safety on Workers' Safety Perception (안전보건에 대한 경영진의 지지가 근로자 안전인식에 미치는 영향)

  • Han, Seung Jo;Bae, Young Min
    • Journal of Digital Convergence
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    • v.19 no.7
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    • pp.155-162
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    • 2021
  • The purpose of this study is to investigate effects of management support for health and safety on workers' safety perception. Since the 1990s, Korea's national competitiveness has been rising rapidly, but efforts to prevent and cope with industrial accidents are still insufficient. Particularly there is a big movement to strengthen corporate responsibility for serious accidents in the 2020s. In this study structural equation model(SEM) was constructed and quantitatively analyzed in order to know how management's support affects the organization, system, and communication related to safety and health in the company, and ultimately how it has an effect on workers' safety perception. 4,169 questionnaires conducted by the Institute for Occupational Safety and Health were used as observation variables, and 5 hypotheses were established and were verified in SEM. As management support increases, organization & institution for a safe workplace, communication related with safety and health within the company become more active. Finally management support has a positive effect on workers' safety perception. The results of this study imply that management needs to increase awareness of the importance of safety and health before all measures such as organizations, institutions, and communication related to safety and health.

A hybrid intrusion detection system based on CBA and OCSVM for unknown threat detection (알려지지 않은 위협 탐지를 위한 CBA와 OCSVM 기반 하이브리드 침입 탐지 시스템)

  • Shin, Gun-Yoon;Kim, Dong-Wook;Yun, Jiyoung;Kim, Sang-Soo;Han, Myung-Mook
    • Journal of Internet Computing and Services
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    • v.22 no.3
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    • pp.27-35
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    • 2021
  • With the development of the Internet, various IT technologies such as IoT, Cloud, etc. have been developed, and various systems have been built in countries and companies. Because these systems generate and share vast amounts of data, they needed a variety of systems that could detect threats to protect the critical data contained in the system, which has been actively studied to date. Typical techniques include anomaly detection and misuse detection, and these techniques detect threats that are known or exhibit behavior different from normal. However, as IT technology advances, so do technologies that threaten systems, and these methods of detection. Advanced Persistent Threat (APT) attacks national or companies systems to steal important information and perform attacks such as system down. These threats apply previously unknown malware and attack technologies. Therefore, in this paper, we propose a hybrid intrusion detection system that combines anomaly detection and misuse detection to detect unknown threats. Two detection techniques have been applied to enable the detection of known and unknown threats, and by applying machine learning, more accurate threat detection is possible. In misuse detection, we applied Classification based on Association Rule(CBA) to generate rules for known threats, and in anomaly detection, we used One-Class SVM(OCSVM) to detect unknown threats. Experiments show that unknown threat detection accuracy is about 94%, and we confirm that unknown threats can be detected.

An Analysis of Iran's Maritime Strategy from a Structural Perspective on Middle East International Relations: Focusing on Defensive Realism (중동 국제관계에 대한 구조적 관점에서의 이란 해양전략에 대한 분석: 방어적 현실주의 관점을 중심으로)

  • Oh, Dongkeon
    • Maritime Security
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    • v.1 no.1
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    • pp.93-117
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    • 2020
  • Four cargo ships were ambushed by bombs in 2019 while navigating in the Strait of Hormuz. It was not clear who attacked those ships, however, many nations including the United States argued that it was Iran due to several reasons. The United States established the maritime collective defense system named International Maritime Security Construct (IMSC) in order to protect the maritime security in the Strait of Hormuz, without disclosure against whom it is aimed. Persian, who uses the Persian language unlike other countries in the Middle East, is the major ethnic group in Iran, and most of them believe Shi'ah Islam while most of the Arabs in the Gulf countries adhere to Sunni Islam. It seems that historic and religious motives caused the bipolar system in the Middle East, however, it is plausible to analyze the system of international affairs in the Middle East via defensive or structural realism. Iran has attempted to maintain its hegemony in the region by supporting Shi'ah muslims in the neighboring countries as well as in the world by using military and economic means. In this context, Iran's maritime strategy is to maintain its maritime hegemony on the Persian Gulf via countering threats and cooperating with friendly navies by using the Islamic Republic of Iran Navy(IRIN) and the Islamic Revolutionary Guard Corps Navy(IRGCN). IRIN acts like other navies in the world: protecting national interest at sea, expending its operational areas to the outer seas, and enhancing cooperation with other navies. Meanwhile, IRGCN plays a role as an asymmetric force at sea. It is composed of small and fast asymmetric assets, which can ambush ships fast and furious. Considering the poor study for Iran's maritime strategy in Korea, analyzing the strategy is meaningful for the Republic of Korea Navy, which has operated the Cheonghae Unit for more than ten years since it has extended its operational area over the Strait of Hormuz. In order not to be drawn into the conflict in the Strait, research on the maritime strategy of Iran and other countries in the Middle East should be started.

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A Study on the Underwater Channel Model based on a High-Order Finite Difference Method using GPUs (그래픽 프로세서를 이용한 고차 유한 차분식 기반 수중채널모델 연구)

  • Bae, Ho Seuk;Kim, Won-Ki;Son, Su-Uk;Ha, Wansoo
    • Journal of the Korea Society for Simulation
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    • v.30 no.1
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    • pp.11-20
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    • 2021
  • As unmanned underwater systems have recently emerged, a high-speed underwater channel modeling technique, which is one of the most important techniques in the system, has received a lot of attention. In this paper, we proposed a high-speed sound propagation model and verified the applicability through quantitative performance analyses. We used a high-order finite difference method (FDM) for wave propagation modeling in the water, and a domain decomposition method was adopted using multiple general-purpose graphics processing units (GPUs) to increase the calculation efficiency. We compared the results of the model we proposed with the analytic solution in the half-infinite media and results of the Virtual Timeseries Experiment (VirTEX) model, which is based on the ray method. Finally, we analyzed the performance of the model quantitatively using numerical examples. Through quantitative analyses of the improvement in computational performance, we confirmed that the computational speed increases linearly as the number of GPUs increases. The computation times are increased by 2 times and 8 times, respectively, when the domain size of computation and the maximum frequency are doubled. We expect that the proposed high-speed underwater channel modeling technique is able to contribute to the enhancement of national defense as an underwater communication channel model and analysis tool to develop the underwater communication technique for the unmanned underwater system.

A Methodology of AI Learning Model Construction for Intelligent Coastal Surveillance (해안 경계 지능화를 위한 AI학습 모델 구축 방안)

  • Han, Changhee;Kim, Jong-Hwan;Cha, Jinho;Lee, Jongkwan;Jung, Yunyoung;Park, Jinseon;Kim, Youngtaek;Kim, Youngchan;Ha, Jeeseung;Lee, Kanguk;Kim, Yoonsung;Bang, Sungwan
    • Journal of Internet Computing and Services
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    • v.23 no.1
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    • pp.77-86
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    • 2022
  • The Republic of Korea is a country in which coastal surveillance is an imperative national task as it is surrounded by seas on three sides under the confrontation between South and North Korea. However, due to Defense Reform 2.0, the number of R/D (Radar) operating personnel has decreased, and the period of service has also been shortened. Moreover, there is always a possibility that a human error will occur. This paper presents specific guidelines for developing an AI learning model for the intelligent coastal surveillance system. We present a three-step strategy to realize the guidelines. The first stage is a typical stage of building an AI learning model, including data collection, storage, filtering, purification, and data transformation. In the second stage, R/D signal analysis is first performed. Subsequently, AI learning model development for classifying real and false images, coastal area analysis, and vulnerable area/time analysis are performed. In the final stage, validation, visualization, and demonstration of the AI learning model are performed. Through this research, the first achievement of making the existing weapon system intelligent by applying the application of AI technology was achieved.