• Journal of IKEEE
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• v.27 no.4
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• pp.425-429
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• 2023

In this paper, the scheme to activate the active elements of reconfigurable intelligent surface(RIS) is proposed. Recently, RIS has been studied as a technology that improves communication coverage and spectral efficiency in wireless communication system. RIS can adjust the phase and amplitude of the received signal, and can ensure better communication performance in areas with many obstacles, such as urban areas. However, due to RIS, the signal undergoes fading twice and performance decrease in communication. Recently, RIS using active reflection elements has been studied to solve these problems. However, if the entire RIS is used as an active reflection element, energy consumption increases. Accordingly, in this paper, we propose a system that utilizes some of the RIS reflective elements as active reflective elements and a scheme for selecting active reflective elements to be activated.

• Journal of Information Processing Systems
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• v.2 no.3 s.4
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• pp.183-188
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• 2006

A RMON agent system, which locates on a subnet, collects the network traffic information for management by retrieving and analyzing all of the packets on the subnet. The RMON agent system can miss some packets due to the high packet analyzing overhead when the number of packets on the subnet is huge. In this paper, we have developed a light-weight RMON agent system that can handle a large amount of packets without packet loss. Our RMON agent system has also been designed such that its functionality can be added dynamically when needed. To demonstrate the dynamic reconfiguration capability of our RMON agent system, a simple port scanning attack detection module is added to the RMON agent system. We have also evaluated the performance of our RMON agent system on a large network that has a huge traffic. The test result has shown our RMON agent system can analyze the network packets without packet loss.

• Proceedings of the IEEK Conference
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• 2002.06b
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• pp.65-68
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• 2002

The verification of software part and HW/SW interface suffer from the absence of the hardware platform at the end of partitioning and coding phase in design cycle. In this paper we present the design of easy verification for hardware design. Hardware and software engineer can verify their software program and hardware design for a chip that is emulated in proposed verification environment. Besides, designer can easily design the DEMO system.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2011.06a
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• pp.727-728
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• 2011

• Journal of Ubiquitous Convergence Technology
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• v.2 no.2
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• pp.59-66
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• 2008

In this study, Software Defined Radio (SDR) technology-based digital filterbank architecture applicable to a multiple-channel processing system such as a wireless mobile communication system using Code Division Multiple Access (CDMA) technology is proposed. The technique includes a micro-processor to redesign Finite Impulse Response (FIR) filter coefficients according to specific system information and to download the filter coefficients to one digital Band Pass Filter (BPF) to reconfigure another system. The feasibility of the algorithm is verified by computer simulation and by implementing a multiple-channel signal generator that is reconfigurable to other system profiles, including those of a Wideband Code Division Multiple Access (WCDMA) system and a CDMA system.

• ETRI Journal
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• v.37 no.1
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• pp.138-146
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• 2015

This paper presents a new non-constraining online optical handwritten signature reconstruction system that, in the main, makes use of a transparent glass pad placed in front of a color camera. The reconstruction approach allows efficient exploitation of hand activity during a signing process; thus, the system as a whole can be seen as a viable alternative to other similar acquisition tools. This proposed system allows people with physical or emotional problems to carry out their own signatures without having to use a pen or sophisticated acquisition system. Moreover, the developed reconstruction signature algorithms have low computational complexity and are therefore well suited for a hardware implementation on a dedicated smart system.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.13 no.10
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• pp.4773-4779
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• 2012

In this paper we propose two types of reconfigurable 3-D beam steering antenna for intelligent or smart antenna system. Proposed antennas are composed of triangular(structure1.) or circuler(structure2.) loop structure and bended dipole antenna structure. This antenna can steer beam pattern of 6 direction at xy-plane state (0, 1, 2) and xz-plane state (3, 4, 5) by 4 switch motion with one antenna element. Antenna structure1. is symmetric equilibrium structures based on feeding point. There is no grounding point. As a result, designed antenna's gain is similar to dipole antenna. Also, As unbalanced structure by using CPWG in the form of a semicircular, structure2. is enhanced directivity. The operation frequency of antenna are 2.5 GHz(Structure1.) and 2.55 GHz(Structure2.), maximum gain is 1.04 ~ 2.06 dBi(Structure1. : Omni-directional beam), 1.6 ~ 4 dBi(structure2. : Directional beam). The overall HPBW is about over $160^{\circ}$ in the both of the xy-plane and xz-plane at structure1. and over $125^{\circ}$ at structure2.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.16 no.12
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• pp.8940-8947
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• 2015

Mixed-model assembly line has been widely used in automotive assembly industry to quickly respond the diverse product demands. But, this model can lead to part confusion, which is a source for assembly errors when parts are physically interchangeable in a mixed-model assembly line. With the recent application of new technologies such as radio frequency identification (RFID) and ZigBee wireless sensor network (WSN) to the assembly process, real-time information has become available in this manufacturing systems through IT infrastructures. At first, this paper presents an RFID application for assembly processes, specifically, for a mixed-model assembly line. Thus, to ensure that parts be picked accurately, each cockpit module on the assembly line is attached with a RFID tag and the tag is scanned using a RFID reader and recognizes the vehicle, and each part of the cockpit module is attached with a barcode and the barcode is scanned by a barcode reader and each part is identified correctly for the vehicle. Second, this paper presents a ZigBee wireless sensor network (WSN) protocol-based application for a reconfigurable mixed-model assembly line of cockpit module to reduce the assembly errors and the cost of the change/reconfiguration on the assembly lines due to the various orders and new models from the motor company, avoiding the wiring efforts and inconvenience by wiring between the several RFID devices and the IT server system. Finally, we presents the operation results for several years using this RFID/ZigBee wireless sensor network (WSN) protocol-based cockpit module assembly line.

• 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.

• Proceedings of the Korea Society for Simulation Conference
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• 2003.06a
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• pp.115-119
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• 2003

It requires a great deal of efforts to maintain a distributed system. What is important here is that we should be able to upgrade/maintain a distributed system without stopping the system in operation. For this, what we need is a dynamic reconfigurable framework for highly available distributed systems. In this paper, we propose objects-hot-swapping methods as a solution to our problem. These methods permit us to dynamically upgrade/expand a system without stopping the system in operation. In addition, we analyze these methods and show that an approach based on proxy is the most efficient. Furthermore, we propose two proxy-based approaches: the first one based on the static proxy provides for a fast execution time but it is difficult to implement. The second one based on the dynamic proxy provides for a slow execution time but it is easier to implement. Finally, we propose a hot swapping framework for these static and dynamic proxy.