• International Journal of Aeronautical and Space Sciences
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• v.9 no.2
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• pp.1-8
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• 2008

This paper presents a real-time algorithm for collision detection, collision avoidance and guidance. Three-dimensional point-mass aircraft models are used. For collision detection, conflict probability is calculated by using the Monte-Carlo Simulation. Time at the closest point of approach(CPA) and distance at CPA are needed to determine the collision probability, being compared to certain threshold values. For collision avoidance, one of possible maneuver options is chosen to minimize the collision probability. For guidance to a designated way-point, proportional navigation guidance law is used. Two scenarios on encounter situation are studied to demonstrate the performance of proposed algorithm.

• Journal of Sensor Science and Technology
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• v.2 no.1
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• pp.57-64
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• 1993

In this paper the normalized innovations squared of a Kalman filter is used to detect a bias level in prediction errors due to target accelerations. The probability density function of the normalized innovation squared is obtained for a steady state Kalman filter, and it is used to calculate the detection probability of the bias level. A typical example is given to compute the detection probability and to plot the maneuver detector operating characteristic curves.

• Journal of Sensor Science and Technology
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• v.1 no.2
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• pp.155-163
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• 1992

The phased array antenna has the ability to perform adaptive sampling by directing the radar beam without inertia in any direction. The adaptive sampling capability of the phased array antenna allows each sampling time interval to be varied for each target, depending on the acceleration of each target at any time. In this paper we design a three-dimensional adaptive tracking algorithm for the phased array radar system with a given set of measurement parameters. The tracking algorithm avoids taking unnecessarily frequent samples, while keeping the angular prediction error within a fraction of antenna beamwidth so that the probability of detection will not be degraded during a track update illuminations. In our algorithm, the target model and the sampling rate are selected depending on the target range and the target maneuver status which is determined by a maneuver detector. A detailed simulation is conducted to test the validity of our tracking algorithm for encounter geometries under various conditions of maneuver.

• Journal of Institute of Control, Robotics and Systems
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• v.19 no.8
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• pp.718-724
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• 2013

In today's automotive industry, there exist several systems that help drivers reduce the possibility of accidents, such as the ADAS (Advanced Driver Assistance System). The ADAS helps drivers make correct and quick decisions during dangerous situations. This study analyzed the performance of the IMM (Interacting Multiple Model) method based on multiple Kalman filters using the data acquired from a driving simulator. An IMM algorithm is developed to identify the current discrete state of neighboring vehicles using the sensor data and the vehicle dynamics. In particular, the driving modes of the neighboring vehicles are classified by the cruising and maneuvering modes, and the transition between the states is modeled using a Markovian switching coefficient. The performance of the IMM algorithm is analyzed through realistic simulations where a target vehicle executes sudden lane change or acceleration maneuver.

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.10 no.2
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• pp.42-54
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• 2011

This study presented an algorithm to detect zigzag driving maneuver that is highly associated with vehicle crash occurrence. In general, the zigzag driving results from the driver's inattention including drowsy driving and driving while intoxicated. Therefore, the technology to detect such unsafe driving maneuver will provide us with a valuable opportunity to prevent crash in the road. The proposed detection algorithm used angular velocity data obtained from a gyro sensor. Performance evaluations of the algorithm presented promising results for the actual implementation in practice. The outcome of this study can be used as novel information contents under the ubiquitous transportation systems environment.

• International Journal of Aeronautical and Space Sciences
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• v.10 no.1
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• pp.37-45
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• 2009

A method of conflict detection and resolution is described by using simple geometric approach. Two VAVs are dealt with and considered as point masses with constant velocity. This paper discusses en route aircraft which are assumed to be linked by real time data bases like ADS-B. With this data base, all DAVs share the information each other. Calculating PCA (Point of Closest Approach), we can evaluate the worst conflict condition between two VAVs. This paper proposes one resolution maneuvering logic, which can be called 'Vector Sharing Resolution'. In case of conflict, using miss distance vector in PCA, we can decide the directions for two VAVs to share the conflict region. With these directions, VAVs are going to maneuver cooperatively. First of all, this paper describes some '2-D' conflict scenarios and then extends to '3-D' conflict scenarios.

• Journal of information and communication convergence engineering
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• v.18 no.1
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• pp.16-21
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• 2020

Owing to the convergence of the communication network with the control system and public network, security threats, such as information leakage and falsification, have become possible through various routes. If we examine closely at the security type of the current control system, the operation of the security system focuses on the threats made from outside to inside, so the study on the detection system of the security threats conducted by insiders is inadequate. Thus, this study, based on "Spotting the Adversary with Windows Event Log Monitoring," published by the National Security Agency, found that event logs can be utilized for the detection and maneuver of threats conducted by insiders, by analyzing the validity of detecting insider threats to the control system with the list of important event logs.

• Ocean Systems Engineering
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• v.7 no.3
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• pp.247-273
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• 2017

Many different engagement situations require naval ships to achieve some level of effectiveness. The performance of the naval ships is very important for such effectiveness. There have been many studies that analyze the effectiveness and the performance. The former are largely related to engagement level simulations, while the latter are largely related to engineering level simulations. However, there have been few studies that consider both the engagement level and the engineering level at the same time. Therefore, this study presents three case studies using engagement simulation of the engineering level to check the performance of the related parameters. First, detection performance simulations are carried out by changing the specifications of the passive sonars of a submarine in different scenarios. Maneuvering performance simulations are carried out by changing the specification of the hydroplanes of a submarine in different scenarios. Lastly, in order to check whether or not our forces would succeed in attacking enemy forces, we perform an engagement simulation with various naval ship models that consist of several engineering level models, such as command systems, weapon systems, detection systems, and maneuver systems. As a result, the performance according to the specifications of the naval ships and weapons is evaluated.

• International Journal of Highway Engineering
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• v.9 no.3
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• pp.29-38
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• 2007

This study investigated the effects of delineation systems on drivers' maneuver and how the effectiveness of delineation system can be further improved according to the road geometry. The experiments were conducted to collect lateral placement data and detection distance data using GPS equipped vehicles. The main results are summarizedas follows. Firstly, installing the delineation facilities on the roads helps drivers to recognize road alignment. Secondly, the detection distance is longer for delineators than for raised pavement marker in tangent section, while there is no difference in curve section. The chevron show the longest detection distance in the curve section, while the raised pavement markers showed no distinctive performance in terms of detection distance and lateral placement. Therefore, we can recommend install delineators in the tangent sections and chevrons in curve sections, based on the analysis results of effects of delineation facilities.

• IEMEK Journal of Embedded Systems and Applications
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• v.8 no.6
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• pp.347-357
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• 2013

Cyber-Physical system(CPS) is characterized by collaborating computational elements controlling physical entities. In CPS, human desire to acquire useful information and control devices anytime and anywhere automatically has increased the necessity of a high reliable system. However, the physical world where CPS is deployed has management complexity and maintenance cost of 'CPS', so that it is impossible to make reliable systems. Thus, this paper presents an 'Autonomic Control System towards High-reliable Cyber-Physical Systems' that comprise 8-steps including 'fault analysis', 'fault event analysis', 'fault modeling', 'fault state interpretation', 'fault strategy decision', 'fault detection', 'diagnosis&reasoning' and 'maneuver execution'. Through these activities, we fascinate to design and implement 'Autonomic control system' than before. As a proof of the approach, we used a ISR(Intelligent Service Robot) for case study. The experimental results show that it achieves to detect a fault event for autonomic control of 'CPS'.