Analysis on Normal Ionospheric Trend and Detection of Ionospheric Disturbance by Earthquake
강선호 Seonho Kang , 송준솔 Junesol Song , 김오종 O-jong Kim , 기창돈 Changdon Kee
22(2) 49-56, 2018
강선호 Seonho Kang , 송준솔 Junesol Song , 김오종 O-jong Kim , 기창돈 Changdon Kee
DOI: JANT Vol.22(No.2) 49-56, 2018
As the energy generated by earthquake, tsunami, etc. propagates through the air and disturbs the electron density in the ionosphere, the perturbation can be detected by analyzing the ionospheric delay in satellite signal. The electron density in the ionosphere is affected by various factors such as solar activity, latitude, season, and local time. To distinguish from the anomaly, therefore, it is required to inspect the normal trend of the ionosphere. Also, as the perturbation magnitude diminishes by distance it is necessary to develop an appropriate algorithm to detect long-distance disturbances. In this paper, normal condition ionosphere trend is analyzed via IONEX data. We selected monitoring value that has no tendency and developed an algorithm to effectively detect the long-distance ionospheric disturbances by using the lasting characteristics of the disturbances. In the end, we concluded the 2nd derivative of ionospheric delay would be proper monitoring value, and the false alarm with the developed algorithm turned out to be 1.4e-6 level. It was applied to 2011 Tohoku earthquake case and the ionospheric disturbance was successfully detected.
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A Case Study on MIL-STD-1760E based Test Bench Implementation for Aircraft-Weapon Interface Testing
김태복 Tae-bok Kim , 박기석 Ki-seok Park , 김지훈 Ji-hoon Kim , 정재원 Jae-won Jung , 권병기 Byung-gi Kwon
22(2) 57-63, 2018
김태복 Tae-bok Kim , 박기석 Ki-seok Park , 김지훈 Ji-hoon Kim , 정재원 Jae-won Jung , 권병기 Byung-gi Kwon
DOI: JANT Vol.22(No.2) 57-63, 2018
In the case of aircraft-launched guided weapons, various interface tests such as MIL-STD-1760 based power source, discrete signal, MUX communication as well as BIT of missile can verify system safety and reliability. The purpose of this case study is to develop a test bench based on MIL-STD-1760E for interoperability testing between aircraft and weapons. We proposed a testing method of the launch sequence based on the defined TIME LINE in the development phase of the missile system from the application of the power of the missile to the targeting, the transfer order, and the missile separation process. Furthermore, it will be a reference model that can maximize the verification scope in the development phase of the air to surface missile system by simulating abnormal situation to the inert missile using the error insertion function.
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Correction Method of High-precision Signal for Aircraft Automatic Test Equipment Using Least Squares Method
이성우 Seong-woo Lee , 김동혁 Dong-hyouk Kim , 김성우 Seong-woo Kim , 서민기 Min-gi Seo , 이철훈 Cheol-hoon Lee
22(2) 64-69, 2018
이성우 Seong-woo Lee , 김동혁 Dong-hyouk Kim , 김성우 Seong-woo Kim , 서민기 Min-gi Seo , 이철훈 Cheol-hoon Lee
DOI: JANT Vol.22(No.2) 64-69, 2018
Automatic test equipment for field maintenance of aircraft mounted equipment is effective for integrated design when operating a small number of aircraft for special purposes. The integrated automatic test equipment identifies commonly used interfaces and is used for branching or generating routes for each unit under test specific inspection. High-precision signals such as RTD, TC, and analog voltage can cause measurement errors due to conduction resistance during signal branching and connection when generating branches and paths. The measurement error caused by the resistance of the wire leads to a lot of restrictions in designing the equipment to be inspected. In this paper, we propose a method of calibrating highly accurate signals of an integrated automatic inspection equipment that minimizes measurement errors of analog voltage and high - precision signals.
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Ground Ejection Tests to verify the Safe Separation of an Aircraft Mounted Store
이종홍 Jong-hong Lee , 최석민 Seok-min Choi , 이민형 Min-hyoung Lee , 이철 Chul Lee , 정재원 Jae-won Jung
22(2) 70-75, 2018
이종홍 Jong-hong Lee , 최석민 Seok-min Choi , 이민형 Min-hyoung Lee , 이철 Chul Lee , 정재원 Jae-won Jung
DOI: JANT Vol.22(No.2) 70-75, 2018
The mounted store on an aircraft shall be subjected to an ground separation test to verify that a safe separation has been made before it is actually installed to the aircraft. In this study, ground ejection test was conducted with dummy missile to verify the stability of the drop on the land. Bomb rack unit essential to testing ground ejection test, operate at high pressure and produce a significant ejection force to push the missile away from any large orifice. Bomb rack unit modified their bombe pressure and orifice diameter to photograph the drop movement of dummy missile with high-speed camera and to analyze their drop displacement and speed. It is considered useful to provide the initial data for the ejection force analysis on aircraft with actual flight and to carry out the ground separation tests of aircraft with future developments.
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Design of Marine IoT Wireless Network for Building Fishing Gear Monitoring System
곽재민 Jae-min Kwak , 김세훈 Se-hoon Kim , 이성렬 Seong-real Lee
22(2) 76-83, 2018
곽재민 Jae-min Kwak , 김세훈 Se-hoon Kim , 이성렬 Seong-real Lee
DOI: JANT Vol.22(No.2) 76-83, 2018
In order to prevent overusing the fishing gear and to reduce discarded fishing gear, there is a need for a technique that can efficiently transmit the information including the type and location of the fishing gear and the user's real name to the fishing boat and the control center using IoT-based communication. In order to do this, it is necessary to be able to confirm the position information of a plurality of buoys that can be identified by the base stations on the land. In this paper, in order to service the maritime IoT communication system, we calculate the link budget between the land base station and the targets on the sea to derive the service coverage. To design a marine IoT radio network for building a fishing gear monitoring system, we calculate link budget for wireless service optimization at sea for NB-IoT using 1.8 GHz frequency band and LoRa service using 900 MHz frequency band. In addition, the link budget between the land base station and buoy, the link budget between the land base station and fishing boat are calculated and the results are analyzed.
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Analysis of the Correlation between Armament/Store Integration Criteria and Aircraft Launch Missile Development Process
최석민 Seok-min Choi , 이종홍 Jong-hong Lee , 김지민 Ji-min Kim , 정재원 Jae-won Jung , Seoung-pil Lee
22(2) 84-89, 2018
최석민 Seok-min Choi , 이종홍 Jong-hong Lee , 김지민 Ji-min Kim , 정재원 Jae-won Jung , Seoung-pil Lee
DOI: JANT Vol.22(No.2) 84-89, 2018
Due to the development of domestic technology, a variety of aircraft launch weapons have been developed, and the importance of aircraft-store integration certification is increasing. The aircraft-Store integration certification is to certify compliance with the armaments/stores integration criteria set out in the Standard ACC and to prove that there is no problem with the safety flight. Therefore, it is necessary to reflect the requirements of the aircraft in the store development process to reduce the design change requirement in the compatibility verification stage. In this paper, the relationship between the Standards ACC, aircraft-store compatibility reference document MIL-HDBK-1763, and the development process of cruise guided weapons have been analyzed. As a result of the analysis, it was concluded that the design changes in the aircraft-store integration certification stage could be reduced if the aerodynamic and structural design requirements were reflected from the conceptual design stage.
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Analysis on Thermochemical Erosion Properties for Thermal Insulation Materials of Graphite Nozzle Throat
김영인 Young-in Kim , 이수용 Soo-yong Lee
22(2) 90-95, 2018
김영인 Young-in Kim , 이수용 Soo-yong Lee
DOI: JANT Vol.22(No.2) 90-95, 2018
In the solid rocket motor (SRM), a thrust of rocket is generated by a nozzle so it is very important device. The nozzle of SRM is a condition of high temperature and high pressure so occurs the erosion by combustion gas. The liquid rocket propulsion systems (LRPSs) cools the nozzle by the fuel and oxidizer but SRM does not cool the nozzle. This paper deal with the development of the oxy-acetylene torch tester and investigate the thermochemical erosion properties for the thermal insulation materials of the graphite rocket nozzle throat through the experiment. The results of experiments are compared with the results of Theoretical model and identify the key factors affecting of erosion. The results is in good agreement with the experimental data.
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Plan of KASS NOTAM Service Provision & System Architecture Through Analysis of Overseas Case
한지애 Ji-ae Han , 이은성 Eunsung Lee , 김연실 Youn-sil Kim , 강희원 Hee Won Kang
22(2) 96-104, 2018
한지애 Ji-ae Han , 이은성 Eunsung Lee , 김연실 Youn-sil Kim , 강희원 Hee Won Kang
DOI: JANT Vol.22(No.2) 96-104, 2018
NOTAM is an announcement that is distributed to flight attendants with status information related to aviation. ICAO, the International Civilian Aviation Organization, recommends that a NOTAM service be provided for the SBAS service in order to use the SBAS signal-based access procedure. To comply with ICAO recommendation, KASS must provide NOTAM service to all aircraft landing using SBAS signal in order to provide APV-I SoL service. Therefore, it is necessary to develop KASS NOTAM system to provide KASS NOTAM service. In this paper, we analyzed the regulations related to NOTAM in Korea and abroad and analyzed the present state of NOTAM service in Korea. Based on this, we propose a method of providing KASS NOTAM service. We analyzed the NOTAM system of WAAS in the US and EGNOS in Europe and analyzed the main functional requirements of the KASS NOTAM system.
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Study on the Removal of the Cable Braid Inside the Missile
은희현 Hee-hyun Eun , 김지민 Ji-min Kim , 이민형 Min-hyoung Lee , 정재원 Jae-won Jung
22(2) 105-110, 2018
은희현 Hee-hyun Eun , 김지민 Ji-min Kim , 이민형 Min-hyoung Lee , 정재원 Jae-won Jung
DOI: JANT Vol.22(No.2) 105-110, 2018
The North Korea nuclear issue is now posing a serious security threat to the Korea and Northeast Asia. Accordingly, the South Korean military is pushing for the introduction of long-range air-to-surface flights and the development of domestic nuclear facilities that can precisely hit North Korea headquarters building and nuclear facility even hundreds of kilometers above the border. In this paper, we removed the cable braid for securing the weight of the missile among several design elements for long-range air-to-surface missile development and estimated and analyzed the resulting performance. The possibility of braid removal was analyzed in terms of crosstalk inside the cable and CS114, RE101 of MIL-STD-461F.
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Constraint Analysis for the Sizing of Roadable PAV Considering Domestic Environments
차재영 Jae-young Cha , 황호연 Ho-yon Hwang , 임은하 Eun-ha Lim , 김석범 Seok-beom Kim
22(2) 111-122, 2018
차재영 Jae-young Cha , 황호연 Ho-yon Hwang , 임은하 Eun-ha Lim , 김석범 Seok-beom Kim
DOI: JANT Vol.22(No.2) 111-122, 2018
At present, the ground transportation system is saturated in many countries including Korea. To overcome this problem, many researches of developing a roadable personal air vehicle (PAV) are being carried out to alleviate traffic congestion and to accomplish door-to-door mobility through three-dimensional traffic system. In this study, the thrust-to-weight ratio, the wing loading, and the power-to-weight ratio that are major design parameters for the sizing of roadable PAVs were calculated under the constraints of ground roll, climb rate, maximum cruise speed, service ceiling, stall speed. Also, in the sizing process, the study was conducted to determine the design point using the graphs of thrust-to-weight ratio, wing loading, power-to-weight ratio, and brake horse power for the mission profiles considering domestic environments and the FAR PART 23 which is the GA class aircraft certification standard.
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Design and Fabrication of a Dual Linear Polarization Sinuous Antenna with Improved Cross Polarization Isolation
김지흥 Jee-heung Kim , 유홍균 Hong-kyun Ryu , 채명호 Myung-ho Chae , 김정훈 Jung-hoon Kim , 박범준 Beom-jun Park , 박영주 Young-ju Park
22(2) 123-132, 2018
김지흥 Jee-heung Kim , 유홍균 Hong-kyun Ryu , 채명호 Myung-ho Chae , 김정훈 Jung-hoon Kim , 박범준 Beom-jun Park , 박영주 Young-ju Park
DOI: JANT Vol.22(No.2) 123-132, 2018
In this paper, we design and fabricate a dual liner polarization sinuous antenna with improved cross polarization isolation (XPI). The proposed antenna is composed of four arm radiators for generating dual linear polarization and excited by wideband microstrip balun with Klopfenstein taper structure. Also, two-step cylindrical cavity structure is applied to reduce back radiation. Honeycomb-typed absorbing material is inserted into the cavity to reduce performance degradation by reflected wave. To enhance cross polarization isolation in low frequency band, resistors are adapted between outer arm and the rim of cavity. We confirmed that the fabricated antenna can be applied for polarization measurement due to improved XPI in the low band.
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The Aircraft-level Simulation Environment for Functional Verification of the Air Data Computer
이동우 Dong-woo Lee , 이재용 Jae-yong Lee , 나종화 Jong-whoa Na
22(2) 133-140, 2018
이동우 Dong-woo Lee , 이재용 Jae-yong Lee , 나종화 Jong-whoa Na
DOI: JANT Vol.22(No.2) 133-140, 2018
In recent years, model-based design techniques have been used as a way to support cost reduction and safety certification in the development of avionics systems. In order to support performance analysis and safety analysis of aircraft and avionics equipment (item) using model based design, we developed a multi-domain simulation environment that inter-works with heterogeneous simulators. We present a multi-domain simulation environment that can verify air data computers and integrated multi-function probes at the aircraft level. The model was developed by Simulink and the flight simulator X-Plane 10 was used to verify the model at the aircraft level. Avionics model functions were tested at the aircraft level and the air data errors of the model and flight simulator were measured within 0.1%.
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4 Way Quadrature Divider Using Metamaterial Transmission Lines
조학래 Hak-rae Cho , 김정표 Jeong-pyo Kim , 구경헌 Kyung-heon Koo
22(2) 141-147, 2018
조학래 Hak-rae Cho , 김정표 Jeong-pyo Kim , 구경헌 Kyung-heon Koo
DOI: JANT Vol.22(No.2) 141-147, 2018
We propose a wideband 4-way quadrature divider for global navigation satellite system (GNSS). The proposed divider consists of one balun and two 2-way quadrature dividers. In the balun, the input power is divided by a wilkinson divider and the out of phase characteristic is achieved by ±90° metamaterial transmission line phase shifters applied two output ports. The structures of two quadrature dividers is similar to that of the balun, but the phase shifters of two output ports are exchanged by ±90° metamaterial transmission line. Metamaterial transmission lines are designed by using five LC loaded transmission line (LCL-TL) unit cells. The fabricated 4 way quadrature divider has the phase characteristic of 90° ± 10° in 1.165 - 1.61 GHz.
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Implementation of Wireless Power Transmission System for Multiple Receivers Considering Load Impedance Variation
김영현 Young Hyun Kim , 박대길 Dae Kil Park , 구경헌 Kyung Heon Koo
22(2) 148-153, 2018
김영현 Young Hyun Kim , 박대길 Dae Kil Park , 구경헌 Kyung Heon Koo
DOI: JANT Vol.22(No.2) 148-153, 2018
This paper proposes a single-input multiple-output (SIMO) self-resonant wireless power transmission system for transmitting power to multiple receivers and the characteristics are simulated and measured. A 600 mm diameter transmission single loop, a 600 mm diameter helical transmission resonant coil, an external diameter 900 mm planar spiral reception resonant coil, and an 80x60 mm2 flat plate square coil as a receiver are used to form a wireless power transmission system 600 mm away with the table structure. For optimal characteristics, the wireless power transmission coils are designed by EM simulation and equivalent circuit analysis, and the characteristics are simulated and measured. The variation of the efficiency with distance from the center of the spiral resonant coil is analyzed and the measured efficiency is 57% for one receiver and for the two receivers, the efficiency is 37% for each receiver.
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Development of Multiplier Operator for Input Signal Control of Electronic Circuits
김종호 Jong-ho Kim , 장홍기 Hong-ki Chang , 권대식 Dae-shik Kwon , 최규식 Gyu-shik Che
22(2) 154-162, 2018
김종호 Jong-ho Kim , 장홍기 Hong-ki Chang , 권대식 Dae-shik Kwon , 최규식 Gyu-shik Che
DOI: JANT Vol.22(No.2) 154-162, 2018
The multiplier circuit is necessary to estimate degradation status of electronic cards in nuclear power plant, but its accuracy is not easy in processing those functions to multiply two input signals. What is important in multiplier circuit is that the multiplication result must be accurate and its linearity must be perfect. We developed and proposed excellent linearity multiplier circuit using operational amplifiers and transistor characteristics, and then proved its validity in this paper. We have made efforts to eliminate nonlinearity components of semiconductors with this circuit in order to ensure excellent linearity of developed multiplier circuit. We conducted multiplication operations through simulation, applying adequate values to each component in order to verify the circuit composed of that method. We showed step-by-step output signals, and then compared the logical analyses and measuring results as simulation results. We confirmed that this method is superior to existing multiplication or linearity.
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Oil Painting Analysis with Statistical Characteristics of Acquired Image
류호 Ho Ryu , 문일영 Il-young Moon
22(2) 163-167, 2018
류호 Ho Ryu , 문일영 Il-young Moon
DOI: JANT Vol.22(No.2) 163-167, 2018
Probabilistic approach is applied to the experiment of Probability Density Function to get the information. Especially this method will be useful to make the montage to compare similarity. But in the case of art painting, it is more difficult than montage image. In this case, we should study the habit of painter with characteristic point in the paintings. Especially we will study characteristic point in the oil paintings to decide truth or falsehood in this paper.
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The Monitoring System of Temperature and Humidity on Vehicle for HACCP
김준배 Joon-bae Kim , 강문성 Moon-sung Kang
22(2) 168-172, 2018
김준배 Joon-bae Kim , 강문성 Moon-sung Kang
DOI: JANT Vol.22(No.2) 168-172, 2018
HACCP is scientific Sanitary control system to ensure food safety with autonomous, systematic and effective way by analysing hazard element that can be occurred in each steps until an end consumer takes food including raw material status, manufacturing, processing, storing, distributing, cooking and specifying the critical control point. In this paper, the temperature and humidity are measured during the transport of food, the stage of its distribution, to ensure systematic and effective management of HACCP, and we designed a monitoring terminal that uses this information to send it to servers periodically and a firmware that implements it. We have confirmed that the data transmitted by the terminal, including the information measured in sub-net, was well stored on the server and the response from the server is well received by the terminal. It is expected to be used for the management of food history, data tracking and statistical data in the future. This system is also considered to be an applicable system for group cafeteria such as schools or workplaces and logistics warehouses for raw materials or food storage and so on.
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A Study on the Self-Authentication Method in Home Quarantine Equipment
김준배 Joon-bae Kim , 강문성 Moon-sung Kang
22(2) 173-178, 2018
김준배 Joon-bae Kim , 강문성 Moon-sung Kang
DOI: JANT Vol.22(No.2) 173-178, 2018
In May 2015, the first case of Middle East Respiratory Syndrome occurred, leaving 186 patients, 38 deaths, and 16,693 quarantine patients. The government has carried out a monitoring of people in contact with the confirmed or suspected patients to prevent the spread of MERS infection. The management staff conducted monitoring of the quarantine subject twice a day during the 14-day period, to check compliance with isolation. However, as the number of people subject to isolation was increased explosively, such issues as the occurrence of residents occurred due to limitations of management personnel. Managers have also admitted that their home quarantine rules have become nominal when they checked the status of quarantine subject by using a call only two or three times a day, and that it is virtually impossible to control when the departees leave without permission. In this paper, home quarantine equipments and their means of authentication are proposed and verified. As a result of the verification, the proposed methods in this paper are expected to be used later as their own authentication method for home quarantine equipments.
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