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Study on the Case of the Asymmetric War (비대칭전 주요사례 연구)

  • Kim, Sung Woo
    • Convergence Security Journal
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    • v.16 no.6_1
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    • pp.25-32
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    • 2016
  • We can not respond asymmetric warfare effectively. The asymmetric operation is performed in asymmetric methods and means with different characteristics and functions to their enemy. And the character of the asymmetric operation have 'heterogeneity' and 'superiority' in principle. The type of asymmetric strategy is complex and diverse. Since we can classify the type of the asymmetric strategy in many different way and we must study in many ways and aspects. When we study asymmetric war previous cases from modern to ancient era, we can find that the key factors of the victory have superiority of the asymmetric strategy and discriminatory measures. The asymmetry is created when one party has to adapt to the strategic environment. If we want to secure a strategic advantage, we must take a number of case studies and countermeasures for asymmetric warfare.

An Experimental Study of Evaporative Heat Exchangers with Mini-channels (물의 증발잠열을 이용하는 미니채널 열교환기의 실험적 연구)

  • Lee, Hyung-Ju;Yoo, Young-June;Min, Seong-Ki
    • Proceedings of the Korean Society of Propulsion Engineers Conference
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    • 2010.11a
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    • pp.245-253
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    • 2010
  • The present study shows some results of developing evaporative heat exchangers with mini-channels. Heat exchangers with three different water paths were manufactured and tested to compare performances of cooling and pressure drop. Among the three types of heat exchangers, Type 2 with full-etching was proved to be the best in the cooling performances for considered operating conditions, and thus it is recommended to adopt Type 2 for its simplicity of production and outstanding performance. However, Type 1 was shown to be better when it is operated at a high air inlet temperature condition. The developed evaporative heat exchanger will be installed in Environmental Control Systems(ECSs) for aerial vehicles, and it can be used effectively in case an ECS is not only limited in its weight and volume but also required to absorb heats without supplying water (or a coolant) for a certain period of time.

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Development of the simulator for marine auxiliary boiler system (선박용 보조 보일러 시스템 시뮬레이터 개발)

  • Kim, Myoung-Hwan;So, Myung-Ok;Jung, Byung-Gun
    • Journal of Advanced Marine Engineering and Technology
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    • v.37 no.2
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    • pp.236-241
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    • 2013
  • It requires long time and high cost for an apprentice engineer to reach the level of getting various experiences of engine space machinery and preparing for emergency situations. Therefore reducing the time and cost, several types of simulator that give the very similar surroundings to the ship engine room, relevant to STCW-95 are used for systematic education and training to get many experiences and good judgement in emergency. Since most simulators that are operated in Korea were imported from foreign countries, it is difficult to directly implant the amendments of STCW Convention and reflect International Maritime Organization (IMO) model courses. This study describe a development of marine auxiliary boiler simulator that makes the apprentice engineer easier to understand the relationship between equipments in steam system such as auxiliary boiler, exhaust gas boiler, and steam turbine.

Fast Distributed Network File System using State Transition Model in the Media Streaming System (미디어 스트리밍 시스템에서의 상태 천이 모델을 활용한 고속 분산 네트워크 파일 시스템)

  • Woo, Soon;Lee, Jun-Pyo
    • Journal of the Korea Society of Computer and Information
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    • v.17 no.6
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    • pp.145-152
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    • 2012
  • Due to the large sizes of streaming media, previous delivery techniques are not providing optimal performance. For this purpose, video proxy server is employed for reducing the bandwidth consumption, network congestion, and network traffic. This paper proposes a fast distributed network file system using state transition model in the media streaming system for efficient utilization of video proxy server. The proposed method is composed of three steps: step 1. Training process using state transition model, step 2. base and decision probability generation, and step 3. storing and deletion based on probability. In addition, storage space of video proxy server is divided into each segment area in order to store the segments efficiently and to avoid the fragmentation. The simulation results show that the proposed method performs better than other methods in terms of hit rate and number of deletion. Therefore, the proposed method provides the lowest user start-up latency and the highest bandwidth saving significantly.

Block Adjustment with GPS/INS in Aerial Photogrammetry (GPS/INS에 의한 항공사진측량의 블럭조정)

  • Park Woon Yong;Lee Kang Won;Lee Jae One;Jeong Gong Uhn
    • Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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    • v.22 no.3
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    • pp.285-291
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    • 2004
  • GPS photogrammetry or the GPS/INS photogrammetry, which are based on the direct measurement of the projection centers and attitude at the moment of camera exposure time through loading the GPS receiver or INS in aircraft. Both photogrammetric methods can offer us to acquire the exterior orientation parameters with only minimum ground control points, even the ground control process could be completely skipped. Consequently, we can drastically reduce the time and cost for the mapping process. In this thesis, test flight was conducted in Suwon area to evaluate the performance of accuracy and efficiency through the analysis of results among the three photogrammetric methods, that is, traditional photogrammetry, GPS photogrammetry and GPS/INS photogrammetry. Test results shows that a large variety of advantages of GPS photogrammetry and GPS/INS photogrammetry against traditional photogrammetry is to be verified. Especially, the number of ground control points for the exterior orientation could be saved more than 70~80%, respectively.

A Study of Security QoS(Quality of Service) Measurement Methodology for Network Security Efficiency (네트워크 보안 효율성 제고를 위한 보안 QoS(Quality of Service) 측정방법론 연구)

  • Noh, Si-Choon
    • Convergence Security Journal
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    • v.11 no.1
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    • pp.39-48
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    • 2011
  • QoS(Quality of Service) is defined "The collective effect of service performance which determines the degree of satisfaction of a user of the service" by ITU-T Rec. E.800. The final goal of information system is to secure the performance efficiency within the required time. The security QoS framework is the modeling of the QoS measurement metrics, the measurement time schedule, instrument, method of measurement and the series of methodology about analysis of the result of measurement. This paper relates to implementing issue and performance measuring about blended mechanism between networking technology and security technology. We got more effectiveness in overall network security, when applying and composing amalgamated security mechanism between network technology and security technology. In this paper, we suggest techniques being used on infrastructure system and also offers a security QoS methodology as a model of more effective way. Methodology proposed in this research has proven that it is possible to measure response time through the scheduled method.

An Efficient Method for Selecting DVOR Installation Site (효율적인 DVOR 설치위치 선정기법)

  • Park, Hyeong-Taek;Hwang, Byong-Won
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.33 no.3A
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    • pp.319-326
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    • 2008
  • All over the world more than 2,000 VORs(VHF Omni-directional Ranges) including 39 in Korea are being operated for formulating air routes. But VOR reveals some difficulties in cost and time when relocating already an installed one due to its poor performance from the interference by its geometrically surrounding obstacles. DVOR(Doppler VOR) which is more popular than CVOR(Conventional VOR) has huge antennas and make it very difficult to assume a sufficient number of proper site candidates for permanent installation. This paper develops an efficient method for predicting proper site of DVOR installation by isolating transmitter from sideband antennas and counterpoise, making the transmitter easily moveable and verifying the performance of DVOR only with a transmitter and an antenna. The method was tested with a real flight measurement for DVOR performance around Gwangju Airport in Korea.

Realization of the Pulse Doppler Radar Signal Processor with an Expandable Feature using the Multi-DSP Based Morocco-2 Board (다중 DSP 구조의 Morocco-2 보드를 이용한 확장성을 갖는 펄스 도플러 레이다 신호처리기 구현)

  • 조명제;임중수
    • The Journal of Korean Institute of Electromagnetic Engineering and Science
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    • v.12 no.7
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    • pp.1147-1156
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    • 2001
  • In this paper, a new design architecture of radar signal processor in real time is proposed. It has been designed and implemented under the consideration to minimize the inter-processor communication overhead and to maintain the coherence in Doppler pulse domain and in range domain. Its structure can be easily reconfigured and reprogrammed in accordance with an addition of function algorithm or a modification of operational scenario. As we designed a task configuration for parallel processing from measures of computation time for function algorithms and transmission time for results by signal processing, data exchange between processors for performing of function algorithms could be fully removed. Morocco-2 board equipped ADSP-21060 processor of Analog Devices inc. and APEX-3.2 developed for SHARC DSP were used to construct the radar signal processor.

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An Empirical Study on the Obstacle Factors of ISMS Certification Using Exploratory Factor Analysis (탐색적 요인 분석을 이용한 기업의 ISMS 인증 시 장애요인에 관한 연구)

  • Park, Kyeong-Tae;Kim, Sehun
    • Journal of the Korea Institute of Information Security & Cryptology
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    • v.24 no.5
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    • pp.951-959
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    • 2014
  • In the past few years, data leakage of information assets has become a prominent issue. According to the National Intelligence Service in South Korea, they found 375 cases of data leakage from 2003 to 2013, especially 49 of cases have been uncovered in 2013 alone. These criminals are increasing as time passes. Thus, it constitutes a reason for establishment and operation of ISMS (Information Security Management System) even for private enterprises. But to be ISMS certified, there are many exposed or unexposed barriers, moreover, sufficient amount of studies has not been conducted on the barriers of ISMS Certification. In this study, we analyse empirically through exploratory factor analysis (EFA) to find the obstacle factors of ISMS Certification. The result shows that there are six obstacle factors in ISMS Certification; Auditing difficulty and period, Consulting firm related, Certification precedence case and consulting qualification, Internal factor, CA reliability and auditing cost, Certification benefit.

A Fast Resource Reallocation Protocol (FRRP) for rt-VBR MPEG-2 video services over ATM Networks (ATM 상에서 실시간 가변비트율 MPEG-2 동영상 서비스를 위한 고속 자원 재할당 프로토콜)

  • 홍승은;장경훈;김덕진;고성제
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.24 no.8B
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    • pp.1426-1437
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    • 1999
  • The introduction of fast packet switching networks such as the ATM leads to the possibility of video services with constant quality. However, the fixed traffic descriptor(TD), which is defined by ATM Forum and ITU-T, can not simultaneously satisfy network efficiency and video quality. This paper presents fast resource reallocation protocol (FRRP) which can provide an effective compromise between network efficiency and video quality. This protocol reallocates the network resources and then adapts the traffic to the reallocated resources. In the proposed method, a video session is divided into several time-intervals according to its generated traffic and TD is calculated which well characterizes the traffic during the specific subdivided interval. In addition, a system model, where MPEG coding algorithm and network control are unified, is proposal and the performance of the FRRP in terms of cell loss rate(CLR) is evaluated though the simulation using real video traffic(Star Wars). Simulation results show that the FRRP has only 5 ~35% CLR of the fixed TD.

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