The Effectiveness of Independent Verification and Validation of Safety-critical Aviation Systems
김영훈 Young-hoon Kim , 유병선 Beong-seon Yoo , 강자영 Ja-young Kang
21(2) 155-162, 2017
김영훈 Young-hoon Kim , 유병선 Beong-seon Yoo , 강자영 Ja-young Kang
DOI: JANT Vol.21(No.2) 155-162, 2017
In recent years, aviation-related safety-critical systems have been developed in Korea, but these products have not satisfied the specified requirements and thus have not been commercialized or commercialized. Due to increasing complexity of the modern aviation system, traditional verification and validation techniques are not sufficient to identify and reduce latent risks in the system. To overcome this shortcoming, a new method which is called `Independent verification and validation (IV&V)` is suggested. However, academic researches on the effectiveness of this independent verification and validation have not been conducted domestically, and it is performed very rarely even overseas. Therefore, in this paper, we investigated the application of independent verification and validation of the safety-critical aviation systems performed by advanced aviation organizations, and analyzed various positive effects on projects. As a result of the analysis, IV&V shows that early error detection rate is increased, potential risk is mitigated early, and the complex reworking probability, which appears later in the development life cycle, is reduced, greatly preventing the development schedule and costs from increasing.
|
Pulse Position Determination using Adaptive Threshold Detector
장재원 Jae-won Chagn , 이상정 Sang Jeong Lee
21(2) 163-170, 2017
장재원 Jae-won Chagn , 이상정 Sang Jeong Lee
DOI: JANT Vol.21(No.2) 163-170, 2017
MLAT which is an independent cooperative surveillance system is applied to increase the positon resoultin of secondary survelliance radar. MLAT uses the hyperboic or hyperboloid position mesurement algorithm. Central processing unit of MLAT calculates target position using time difference of arrival (TDOA) which can be solved from time of arrival (TOA) information of each receivers (at least 4 receivers). To increase position resolution of MLAT which use TDOA, TOA which is transfer time from tranmitter to receiver shold be calculated with precision time resolution in receiver. This paper explained the MLAT system briefly and explained ATD which is one of means of calcuating pulse position. ATD is applied to solve the deviation of pulse position due to different amplitude of signals in mulitiple receivers. In this paper, to analysis the performance of ATD, the simulation result of LAS and CDS was compared with the simulation result of basic threshold method.
|
Development of the Localization Algorithm for a Hovering-type Autonomous Underwater Vehicle using Extended Kalman Filter
강현석 Hyeon-seok Kang , 홍승민 Sung-min Hong , 서주노 Joo-no Sur , 김동희 Dong-hee Kim , 정재훈 Jae-hun Jeong , 정성훈 Seong-hoon Jeong , 최형식 Hyeung-sik Choi , 김준영 Joon-young Kim
21(2) 171-178, 2017
강현석 Hyeon-seok Kang , 홍승민 Sung-min Hong , 서주노 Joo-no Sur , 김동희 Dong-hee Kim , 정재훈 Jae-hun Jeong , 정성훈 Seong-hoon Jeong , 최형식 Hyeung-sik Choi , 김준영 Joon-young Kim
DOI: JANT Vol.21(No.2) 171-178, 2017
In this paper, in order to verify the performance of a localization algorithm using GPS as an auxiliary sensor, the algorithm was applied to a hovering-type autonomous underwater vehicle (AUV) to perform a field test. The applied algorithm is an algorithm to improve the accumulated positional error of dead reckoning using doppler velocity logger(DVL) and tilt-compensated compass module (TCM) mounted on the AUV. GPS when surfaced helps the algorithm to estimate the position and the heading bias error of TCM for geodetic north, which makes it possible to perform dead reckoning on north-east-down (NED) coordinates. As a result of field test performing heading control, it was judged that the algorithm could improve the positional error, enhance the operational capability of AUV and contribute to the research of underwater navigation depending on a magnetic compass.
|
An Interrogator for Active Acquisition of Airspace in Active Multilateration
고영목 Young-mok Koh , 김용학 Yong-hak Kim , 김수홍 Su-hong Kim
21(2) 179-186, 2017
고영목 Young-mok Koh , 김용학 Yong-hak Kim , 김수홍 Su-hong Kim
DOI: JANT Vol.21(No.2) 179-186, 2017
This paper is concerned with an interrogator capable of constructing a interrogation scenario for acquiring active airspace to the intruding aircraft into the surveillance area of the MLAT system. In the MLAT system, the interrogator is an important device used to carry out the interrogation towards the aircraft within the surveillance airspace in the appropriate surveillance scenario. Unlike a conventional SSR`s interrogation methods that interrogate for airplanes flying within a certain range, the MLAT system requires a interrogation system that can actively interrogate from remote to near range, or according to operational scenarios, for aircraft intruding into the surveillance range. The interrogator implemented in this paper can be used for interrogating and monitoring aircraft within each surveillance airspace using whisper-shout algorithm according to varying output power based on the actual operation distance.
|
Compensation of the Distorted WDM Channels Depending on the Control Position of Net Residual Dispersion in Dispersion-managed Optical Link with the Randomly Distributed SMF Lengths and RDPS
이성렬 Seong-real Lee
21(2) 187-192, 2017
이성렬 Seong-real Lee
DOI: JANT Vol.21(No.2) 187-192, 2017
The compensation characteristics of the distorted WDM channels compensated for by dispersion management (DM) and optical phase conjugation in the long-haul (50 fiber spans × 80 km) transmission link with the randomly distributed single mode fiber (SMF) length and residual dispersion per spans (RDPS) are investigated as a function of the arrangement of SMF and dispersion compensating fiber (DCF) and the control position of net residual dispersion (NRD). It is confirmed that the compensation effect of the distorted WDM channels strongly depends on the arragement of SMF and DCF, rather than the control position of NRD.
|
Dual Band-notched Monopole Antenna for 2.4 GHz WLAN and UWB Applications
이기용 Ki-yong Lee , 이영순 Young-soon Lee
21(2) 193-199, 2017
이기용 Ki-yong Lee , 이영순 Young-soon Lee
DOI: JANT Vol.21(No.2) 193-199, 2017
In the paper, a dual band-notched monopole antenna is proposed for 2.4 GHz WLAN (2.4 ~ 2.484 GHz) and UWB (3.1 ~ 10.6 GHz) applications. The 3.5 GHz WiMAX band notched characteristic is achived by a pair of L-shaped slots instead of the previous U-shaped slot on the center of the radiating patch, whereas the 7.5 GHz band notched characteristic is achived by C-shaped strip resonator placed near to the microstrip feed line. The measured impedance bandwidth (|S11|≤-10dB) is 8.62 GHz (2.38 ~ 11 GHz) which is sufficient to cover 2.4 GHz WLAN and UWB band, while measured band-notched bandwidths for 3.5 GHz WiMAX and 7.5 GHz bnad are 1.13 GHz (3.15 ~ 4.28 GHz) and 800 MHz (7.2 ~ 8 GHz) respectively. In particular, it has been observed that antenna has a good omnidirectional radiation patterns and higher gain of 2.51 ~ 6.81 dBi over the entire frequency band of interest.
|
Implementation of Golf Swing Accuracy Analysis System using Smart Sensor
주재한 Jae-han Ju
21(2) 200-205, 2017
주재한 Jae-han Ju
DOI: JANT Vol.21(No.2) 200-205, 2017
Modern sports are developing into sports science that incorporates science and various analytical simulation systems for improving records are being developed, and they are helping to improve actual game records. Therefore golf which is one of various sports events, has been popularized among the hobbyists and the general public and there is an increasing demand for correcting the movement attitude of the person. In response to these demands, many systems have been developed to analyze and correct golf swing postures. The golf swing accuracy analysis system analyzes the moments that can not be seen with the naked eye and guides them to understand easily. It can improve the golf swing motion through immediate feedback due to the visual effect. Using the knowledge of golf swing motion collected from golf swing video, we improved reliability. In addition, it provides the ability to visually check and analyze your golf swing video, allowing you to analyze each segment based on various golf swing classification methods.
|
Implementation of Access Control System Suitable for Meteorological Tasks in Grid Computing Environment
나승권 Seung-kwon Na , 주재한 Jae-han Ju
21(2) 206-211, 2017
나승권 Seung-kwon Na , 주재한 Jae-han Ju
DOI: JANT Vol.21(No.2) 206-211, 2017
Recently computing devices by connecting to a network, grid computing, the next generation of digital neural networks that provide maximum service will connect all of the computer such as a PC or server, PDA into one giant network makes the virtual machine. Therefore, we propose the grid computing implementation model to be applied to meteorological business field as follows. First, grid computing will be used for tasks such as the development of numerical models below the mid-scale or test operations, and the final backup of the weather supercomputer. Second, the resources that will constitute grid computing are limited to business PCs and Linux servers operated by the central government considering operational efficiency. Third, the network is restricted to the LAN section, which suggests the implementation of high performance computing.
|