• Journal of Electrical Engineering and Technology
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• v.12 no.5
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• pp.2051-2066
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• 2017

This paper deals with reconfigurable secured mobile systems where the reconfigurability has the potential of providing a required adaptability to change the system requirements. The reconfiguration scenario is presented as a run-time automatic operation which allows security mechanisms and the addition-removal-update of software tasks. In particular, there is a definite requirement for filtering and intrusion detection mechanisms that will use fewer resources and also that will improve the security on the secured mobile devices. Filtering methods are used to control incoming traffic and messages, whereas, detection methods are used to detect malware events. Nevertheless, when different reconfiguration scenarios are applied at run-time, new security threats will be emerged against those systems which need to support multiple security objectives: Confidentiality, integrity and availability. We propose in this paper a new approach that efficiently detects threats after reconfigurable scenarios and which is based on filtering and intrusion detection methods. The paper's contribution is applied to Android where the evaluation results demonstrate the effectiveness of the proposed middleware in order to detect the malicious events on reconfigurable secured mobile systems and the feasibility of running and executing such a system with the proposed solutions.

• The Transactions of the Korean Institute of Electrical Engineers D
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• v.55 no.12
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• pp.518-525
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• 2006

This paper presents the adaptive robust control method for the flight control systems with model uncertainties. The proposed control system can be composed simply by a combination of the adaptive dynamic surface control (DSC) technique and the self recurrent wavelet neural network (SRWNN). The adaptive DSC technique provides us with the ability to overcome the 'explosion of complexity' problem of the backstepping controller. The SRWNNs are used to observe the arbitrary model uncertainties of flight systems, and all their weights are trained on-line. From the Lyapunov stability analysis, their adaptation laws are induced and the uniformly ultimately boundedness of all signals in a closed-loop adaptive system is proved. Finally, simulation results for a high performance aircraft (F-16) are utilized to validate the good tracking performance and robustness of the proposed control system.

• International Journal of Aeronautical and Space Sciences
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• v.8 no.1
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• pp.79-86
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• 2007

In this paper, an adaptive control algorithm using system identification is proposed for an aircraft fault tolerant control system. A discrete state-space system is reformulated to be the ARX model which has the advantage in handing variable structure systems. Discrete model reference adaptive control is used to make the output of fault system follow the output of reference model. To validate the performance of the proposed control scheme, numerical simulations are performed for the high performance aircraft with control surface damage.

• International Journal of Aerospace System Engineering
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• v.4 no.1
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• pp.1-8
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• 2017

This paper proposes the load distribution control allocation technique. The proposed method is designed by combining a conventional control allocation method with load distribution ability in order to reduce the stress acting on ailerons. By designing the weighting matrix as a function of the load distribution rule, the optimal deflection angles of each surface to satisfy both control goal and load distribution can be achieved. Moreover, rule based fault-tolerant control technique is also proposed. The rules are generated by considering both dominant control surfaces and the ratio of load distribution among surfaces. The performance of the proposed method is evaluated through numerical simulations.

• Journal of Institute of Control, Robotics and Systems
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• v.8 no.11
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• pp.928-934
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• 2002

A natural way to cope with fault tolerant control (FTC) problems is to modify the control parameters according to an online identification of the system parameters when a fault occurs. However. due to not only difficulties Inherent to the online multivariable identification in closed-loop systems, such as modeling errors, noise or the lack of excitation signals, but also long time requirement to identify the post-fault system and implemeutation of control problems during the identification process, we propose an alternative approach based on the observer-based fault detection and isolation (FDI) and model reference adaptive control (MRAC). The proposed robust fault diagnosis method is based on a bank of observers. We also propose a model reference adaptive control with changeable reference models according to the occurred faults. Simulation results of a flight control example show the validity and applicability of the proposed algorithms.

• Journal of IKEEE
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• v.17 no.4
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• pp.407-417
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• 2013

In this paper, a reconfigurable peripheral unit for LED lighting communication is presented. Embedded lighting devices require various communication protocols. Usually, serial communication protocols and lighting control communication protocols such as DALI, DMX512, UART, SPI, IrDA, etc. are used in lighting devices. When the requirements of communication protocols are satisfied with separate IPs, the cost and the power consumption can considerably increase. We propose a reconfigurable communication peripheral unit which uses analysis of signal formats of the protocols. The gate count of the reconfigurable peripheral unit uses only 57% of the gate count of the separate implementation. Also, in this paper, a mapping table based DALI-ZigBee interfacing method for flexible lighting network configurations is proposed. Using this method, various DALI-ZigBee network systems can be easily set up. An LED lighting system platform is implemented to verify the operation of the DALI-ZigBee interfacing method. The reconfigurable peripheral unit and the DALI-ZigBee interfacing method can be efficiently used to implement various wired/wireless lighting communication systems.

• Journal of the Korean Society of Manufacturing Technology Engineers
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• v.8 no.5
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• pp.54-62
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• 1999

This paper describes the design and implementation of a PC(personal computer) based open architecture machine tool controller. The hardware of open architecture CNC has generally a motion control board on a PC for controlling a servo motor. But this paper describes open architecture hardware that consists of a PC, a counter board a DAC board and a DIO board only. This makes it easy to generate CNC software module in a hardware-independent way. The proposed open architecture CNC software runs on the MS-Windows NT. The paper describes a method of con-trolling servo motors using a real-time timer of MS-Windows NT and a commercial real-time operating system on the MS-Windows. NT. An open and reconfigurable software module is made up of an object and an API(application programming interface). Using the object and the API a new CNC system can be quickly configured to control dif-ferent machine tools. The proposed open architecture CNC system is applied to 4-axis lettering center.

• Journal of the Institute of Electronics Engineers of Korea SD
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• v.40 no.8
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• pp.619-630
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• 2003

We present a method of runtime configuration scheduling in reconfigurable SoC design. As a model of computation, we use a popular formal model of computation, hierarchical FSM (HFSM) with synchronous dataflow (SDF) model, in short, HFSM-SDF model. In reconfigurable SoC design with HFSM-SDF model, the problem of configuration scheduling becomes challenging due to the dynamic behavior of the system such as concurrent execution of state transitions (by AND relation), complex control flow (HFSM), and complex schedules of SDF actor firing. This makes it hard to hide configuration latency efficiently with compile-time static configuration scheduling. To resolve the problem, it is necessary to know the exact order of required configurations during runtime and to perform runtime configuration scheduling. To obtain the exact order of configurations, we exploit the inherent property of HFSM-SDF that the execution order of SDF actors can be determined before executing the state transition of top FSM. After obtaining the order information and storing it in the ready configuration queue (ready CQ), we execute the state transition. During the execution, whenever there is FPGA resource available, a new configuration is selected from the ready CQ and fetched by the runtime configuration scheduler. We applied the method to an MPEG4 decoder and IS95 design and obtained up to 21.8% improvement in system runtime with a negligible overhead of memory usage.

• Journal of KIISE
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• v.44 no.5
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• pp.476-485
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• 2017

The tactical operation centers of future anti-aircraft missile systems provide the environment for the research on future air threats, tactical information, integrated battlefield environment creation and management, engagement control and command and control algorithms. To develop the key functional elements of integrated battlefield situation creation and processing and tactical operation automation processing operations, battery/battalion tactical operation control and reconfiguration design software are required. Therefore, the algorithm software of each function and the tactical operation display software and link software for interworking between equipment were developed as reconfigurable through a data-centric design. In this paper, a tactical operation display framework that can be reconfigured on the operation display of the tactical operations according to the battery/battalion is introduced. This tactical operation display framework was used to develop a common data model design for the reconfigurable structure of multi-role tactical operations with battery / battalion and mission views, and a display configuration tool that provides a tactical operation display framework for view development was also developed using the MVC pattern. If the tactical operation display framework is used, it will be possible to reuse the view design through the common base structure, and a view that can be reconfigured easily and quickly will also be developed.

• Proceedings of the Korean Operations and Management Science Society Conference
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• 2004.05a
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• pp.471-474
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• 2004

In order to quickly respond to the rapidly changing manufacturing environment, it is imperative for the system to have such capabilities as flexibility, adaptability, reusability, etc. One of the promising approaches for new manufacturing paradigm satisfying those capabilities is the fractal manufacturing system (FrMS). FrMS is based on the concept of autonomously cooperating and self-reconfigurable agents referred to as fractals. In this paper, a fractal template is proposed to have both fractal-specific and agent-specific characteristics and proper techniques for implementation are also selected. The proposed template can be easily extended to the platform of FrMS which supports simulation, shop flow control, and other research issues existed in the manufacturing systems. An example of applying the proposed template to the simulation is also presented.