• Title/Summary/Keyword: 항행위해요소

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A Study on an efficient handover scheme for real-time multicast services in PMIPv6 network (Proxy Mobile IPv6 기반 실시간 멀티캐스트 서비스를 위한 효율적인 핸드오버 방안에 대한 연구)

  • Kim, Jung-Hoon;Ryoo, In-Tae;Na, Won-Shik
    • Journal of Advanced Navigation Technology
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    • v.14 no.4
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    • pp.537-544
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    • 2010
  • The PMIPv6 is a network controlled mobility management protocol in which mobile nodes never participate in IP mobility protocol signaling. One issue in using PMIPv6 for multicast service is that a new component should be added as the mobility management functions are located not on the device but on the network. Currently, standardization activities for providing muticast services with PMIPv6 have been actively in progress. This paper addresses some issues about the on-going standardization works for providing efficient real-time multicast services with PMIPv6, and proposes a scheme for minimizing hand over delays and packet losses by using a new neighbor cell reporting method. The proposed scheme has been verified to outperform the existing scheme in hand over delay and packet loss perfonnrmces by using computer simulations.

A Warning Threshold Proposal for Operation Improvement of Maritime DGPS Reference Station (해양용 DGPS 운영성 개선을 위한 시스템 경고 임계값 제안)

  • Choi, Yong Kwon;Lee, Ju Hyun;Son, Seok Bo;Lee, Sang Jeong
    • Journal of Advanced Navigation Technology
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    • v.21 no.1
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    • pp.12-20
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    • 2017
  • A maritime DGPS in Korea offers pseudo-range correction information and monitors integrity of correction data by using multiple GNSS receivers. The maritime DGPS reference station and integrity monitor service sets alarm threshold value about integrity monitoring parameters for preventing service interruption status. However there is no way to avoid system interruption according to malfunction of backup systems and outside factors. Therefore, in this paper, warning threshold values were proposed for maritime DGPS operator can be counteract in advance. And Markov analysis method was carried out for selection of these warning threshold values.

Establishing the Importance Institution for Prevention of Human Error (인적오류 예방을 위한 제도의 상대적 중요도 분석)

  • Moon, Woo-Choon;Kim, Woong-Yi
    • Journal of Advanced Navigation Technology
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    • v.17 no.4
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    • pp.377-385
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    • 2013
  • Since the late 1950s, concerted efforts to reduce the accident rate in aviation have yielded unprecedented levels of safety. Although, the overall accident rate has declined considerably over the years, unfortunately reductions in human error-related accidents in aviation have failed to keep pace with the reduction of accidents due to environmental and mechanical factors. Today, a very large percentage of all aviation are attributable, directly or indirectly, to some form of human error. As a result of many study, a range of prevention of human error have been developed. but each of kind is lack of a precision, effectiveness and seem to be considered for aspect of deficiency as an systematic accessibility. So, we're going to analysis the most effective and systematic prevention of human error and study on consolidating method for human error and aviation safety. In this study, several alternatives for the prevention of human errors a priority to understand and solve problems by identifying the implications for human error to be presented.

Design of Lightning Induced Transient Protection Circuit for Avionics Equipment Considering Parasitic Inductance (기생 인덕턴스를 고려한 항공기 탑재장비의 간접낙뢰 보호회로 설계)

  • Sim, Yong-gi;Cho, Seong-jin;Kim, Sung-hun;Park, Jun-hyun;Han, Jong-pyo
    • Journal of Advanced Navigation Technology
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    • v.21 no.5
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    • pp.459-465
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    • 2017
  • In this paper, we introduce the design consideration of the lightning induced transient protection circuit for the indirect lightning strike on the avionics equipment. The lightning induced surge voltage, which is so-called as indirect effects of lightning, may cause a functional failure or physical damage to the electrical and electronic equipment of aircraft. In order to protect the electrical and electronic equipment of aircraft from the indirect effects of lightning, we should analyze the effect of lightning strike on aircraft and consider applying protection design for each avionics device. However, lightning induced transient protection circuits can have unintended consequences because parasitic inductance elements are exist in PCB and TVS diodes. In this paper, we introduce the design method of the protection circuit considering the parasitic inductance of the protection circuit. In addition, we show the result of verification test performed to validate the protection circuits for indirect effects of lightning.

Performance Evaluation of UWB Positioning System in Ultra Wideband Indoor Environment (광대역 실내 환경에서 UWB 위치 추정 시스템의 성능 평가)

  • Roh, Jae-sung
    • Journal of Advanced Navigation Technology
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    • v.25 no.5
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    • pp.357-362
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    • 2021
  • UWB(ultra wide band) communication systems employ short pulses to transmit information which spreads the signal energy over a very wide frequency spectrum. Received signal-to-noise power ratio of UWB signals is an important factor in determining the accuracy of a positioning system. As the signal to noise power ratio gets higher, positioning errors decrease since noise becomes less effective. Calculation of signal to noise power ratio as a function of communication distance provides important guidelines for the system design. And the performance of a positioning system also depends heavily on the channel model. As a result of the analysis, it was found that the performance of the received signal to noise power ratio according to the communication distance was better in the LOS channel environment than in the Non LOS(line of sight) channel environment. And as the symbol interval of the preamble signal increases at a specific communication distance, the channel capacity of the UWB system increases.

Establishment of Flight Inspection Evaluation Items and Optimal Design of SBAS Performance Test Measurement Equipment by Analyzing Evaluation Items and Essential Components of Korean SBAS (한국형 SBAS의 평가항목 및 필수 구성요소 분석을 통한 비행검사 평가항목 수립 및 SBAS 성능 시험 측정 장비 최적 설계 방안)

  • Kim, Young-Bin;Hong, Gyo-Young
    • Journal of Advanced Navigation Technology
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    • v.25 no.1
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    • pp.78-83
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    • 2021
  • Due to rapidly increasing air traffic congestion and airspace restrictions, the International Civil Aviation Organization (ICAO) is urging all aircraft to use SBAS by 2025, in order to implement Performance-based navigation to increase airspace capacity. In line with this, research and development of Korean-style SBAS, which reflects the characteristics of Korea's airspace environment, continues in Korea. Since there is no flight inspection procedure for performance testing and verification of SBAS in Korea yet, this paper analyzes FAA, ICAO Regulations, and laws enacted by the Ministry of Land, Infrastructure and Transport to derive essential evaluations and parameters of Korean SBAS, and presents the optimal design using RTK-DGPS as a position fixing system.

Implementation of Elliptic LPF using LTCC Passive Library Elements for 5G Band (LTCC 수동소자 라이브러리를 활용한 5G 대역 일립틱 LPF 구현)

  • Cho, Hak-Rae;Koo, Kyung Heon
    • Journal of Advanced Navigation Technology
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    • v.24 no.6
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    • pp.573-580
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    • 2020
  • In this paper, the characteristics of the inductor and capacitor, which are the basic components of the circuit, are constructed in a form that can be used in the LTCC multilayer. The inductors and capacitors used for the analysis were designed with rectangular spiral structures and MIM structures inside dielectrics with a dielectric constant of 7, respectively. The measured results were extracted from each element of the equivalent circuit proposed by the curve fitting method and verified the validity of the proposed equivalent circuit based on the extracted results. The analyzed inductor and capacitor were implemented in the form of library and proved its usefulness by applying to Elliptical type 5th LPF design. The LPF was measured through practical production, and as a result, the insertion loss in the passband DC ~ 3.7 GHz was up to 1.0 dB, the return loss was 19.2 dB, and the attenuation in the rejection band was 23.9 dB, which was close to the design goal.

A Study on the operation of Air Traffic Control System for a Korean Light Aircraft Carrier (한국형 경항공모함 항공관제장비 운영에 대한 연구)

  • Youn-chul Choi;Yong-tae Jung;Young-jin Cho;Do-hyun Kim;Won-hyuk Choi;Yoon-Su Park
    • Journal of Advanced Navigation Technology
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    • v.27 no.2
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    • pp.173-181
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    • 2023
  • Aircraft carriers need to maintain an orderly flow of aircraft in order for military ships to conduct combat through aircraft. Maintaining aircraft flow is an important factor in strengthening ship and aviation safety. In order to maintain aircraft flow, it is essential to develop a state-of-the-art air control system that provides higher quality control information by simultaneously accommodating radar-based monitoring information and monitoring information based on CNS integrated technology. Based on this point, this study describes the function and operation method of specific control equipment for the operation of the Aviation Support System and Air Traffic Control System required to operate light aircraft carriers in Korea based on overseas cases.

Time Synchronization Algorithm based on FLL-Assisted-PLL for Telemetry System (FLL-Assisted-PLL 기반의 텔레메트리 시스템 정밀 시각동기 알고리즘)

  • Geon-Hee Kim;Mi-Hyun Jin
    • Journal of Advanced Navigation Technology
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    • v.26 no.6
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    • pp.441-447
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    • 2022
  • In this paper, we propose a FLL-assisted-PLL based time synchronization algorithm for telemetry systems where frequency and phase errors exist in time synchronization pulse. The telemetry system may analyze the flight state by acquiring the state information in the distributed system. Therefor, in order to collect each state information without errors, precise time synchronization between the master and the slave is required. At this time, the master's time pulse have frequency and phase changes that can be caused by external and internal factors, so a method to maintain precision time synchronization is essential to provide telemetry data continuously. We propose the FLL-assisted-PLL based algorithm that is capable of high-speed synchronization and has high time synchronization accuracy. The proposed algorithm is verified through python simulation, and the VHDL Logic has been implemented in FPGA to check the performance according to the frequency errors and phase errors.

Study on the EMC Engineering for Fixed Installations (복합설비를 위한 EMC 엔지니어링 연구)

  • Young-Heung Kang
    • Journal of Advanced Navigation Technology
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    • v.27 no.6
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    • pp.798-803
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    • 2023
  • In the industrial internet of things (IIoT) industry, including smart factories, there are many cases where electronic devices are complexly combined and installed due to the recent development of intelligent information technology. Electromagnetic waves generated from such complex facilities affect other devices and services, which can lead to safety issues. The problem such as electromagnetic interference (EMI) and electromagnetic compatibility (EMC) generated when controlling complex facilities is an essential element that must be solved, and the engineering basis for EMI and EMC must be established to foster the industry of complex facilities. Therefore, in this study, EMC & EMI engineering demonstration cases for solar power fixed facilities using the national standard guideline have been analyzed. The results show that the electromagnetic risk indices in the solar power facilities have been degraded up to control level, and a national EMC engineering system has been proposed for complex facilities.