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Keynote Speakers

Prof. Usik Lee
Inha University, South Korea
Title Introduction to Spectral Element Method (SEM) with Applications to Smart Structures
Abstract The vibrating shape of a structure varies as the frequency of vibration varies. Thus, the standard finite element model formulated by using the frequency independent polynomial shape functions may require the subdivision of a structure element into finer elements in order to improve the solution accuracy, especially at high frequency. However, if the frequency dependent (or dynamic) shape functions are adopted to formulate the finite element model, such a finer subdivision may not be necessary. This idea has led to the exact dynamic stiffness matrix method. Because the exact dynamic stiffness matrix is the stiffness matrix formulated in the frequency domain, they can be readily assembled by using the exactly same method that used in the standard finite element method (FEM). In the literature, the FFT-based dynamic stiffness matrix method is often named spectral element method (SEM). Because the exact dynamic stiffness matrix is formulated from the exact dynamic shape functions which satisfy the governing equations of motion, it represents the dynamic behavior of a structural element exactly. Thus, the SEM is often justifiably referred to as an exact element method. Accordingly, in contrast with the standard FEM, the SEM enables one to use only one finite element for a uniform structural member, regardless of its length, without requiring any further subdivision of the structural member to improve the solution accuracy. This may reduce the total number of degrees of freedom used in the analysis to significantly lower the computation cost. In this keynote speech, the fundamental theory of SEM will be introduced first, and then its application to a typical one-dimensional smart structure will be presented as an illustrative example problem.
Prof. Yusaku Fujii
Gunma University, Japan
Title Biomechanical Properties Measurements Using the Levitation Mass Method (LMM)
Abstract The interaction between human and machine are important for developing human-friendly machines. Biomechanical properties measurements using the Levitation Mass Method (LMM) are reviewed. The levitation mass method (LMM) has been proposed and improved by authors. In the LMM, an rigid object is levitated with a small friction using an aero-static linear bearing. The total force acting on the object (the moving part of the bearing) is measured as the product of mass and acceleration of the object, i.e. F=Ma. In the method, only the Doppler shift frequency of the laser beam reflected by the object is accurately measured using an optical interferometer. Subsequently, the velocity, position, acceleration, and inertial force of the object are calculated from this frequency. Force controllability of human arm, impact response of human arm and impact response of human palm are accurately measured using the LMM. The deeper understanding of properties/functions of human is important for improving the all the fields of engineering, since all the engineering should be for improving human life. In the speech, the present status and the future prospect of our research are discussed.
Prof. Takuo Nakashima
Tokai University, Japan
Title Detection System for Anomaly Attacks using Statistical Methods
Abstract The computer systems connected to the Internet are exposed the threats of DoS/DDoS attacks aiming to destroy the server functions. The malicious users hijack the vulnerable PCs and generate the attacking PCs called as BOT. A large number of BOTs sends a huge number of anomaly packets to paralyze the server functions. The early detection methods for these anomaly packets are required to sustain the damage of DoS/DDoS attacks. Our previous researches have clarified that the source IP address and destination port number are efficient statistical variables to view the anomaly packet property.
In this speech, we show EMMM (Entropy-based Multidimensional Mahalanobis-distance Method) method for entropy value and CSDM (χ square based Space Division Method) method for χ square value using multi statistical variables. The experiments to verify our two proposed methods were conducted using source IP address, destination port number and arriving interval of packets. We could extract the following results. Firstly, EMMM could decrease the value of False-Positive and False-Negative. Secondly, CSDM could increase the F-metric. In the experiments using the same condition of parameters such as probability valuables and window width, CSDM enlarges the F-metric compared to EMMM.
Prof. Somsak Mitatha
King Mongkut’s Institute of Technology Ladkrabang, Thailand
Title Signal Processing via Micro Ring Resonator for All-optical Arithmetic Elements
Abstract We propose a design of the secured packet switching using the nonlinear behaviors of Gaussian pluses in a micro ring resonator. The use of chaotic signals are generated by a Kerr effects nonlinear type, where the control input power or device parameters can be used to specify the output signals. Results obtained have shown the potential of using such a proposed device for the tunable band-pass and band-stop filters, in which the packet switching data can be performed and secured. The nonlinear behavior of light known as bifurcation which can be generated to form the start-stop bits of secure digital codes for optical packet switching data and digital encoding of chaotic signals in nonlinear micro ring resonator.
The generated chaotic signals can be formed as the logical pulses “1” or “0” using the signal quantizing method. Systems of the simultaneous fast and slow light generation using Gaussian pluses propagating within the nonlinear micro ring resonators. Results show the selected down-link and up-link frequency bands are 500 MHz and 2 GHz, respectively. Such small device system can be implemented within the mobile telephone hand set. And we can use a micro-ring resonator to compose optical gate such as NOT gate, OR gate, AND gate, NAND gate, all-optical arithmetic elements and its can apply to use for other application such as DNA codes. The DNA codes can be generated and formed by the logical pulses “A” or “T” or “C” or “G” by using the chaotic signal quantizing method, which can be randomly coded by controlling the specific optical input coupling power, i.e. coupling coefficient and ring radii. Simulation results obtained have shown that the packet switching data can be high secured by using the DNA codes. The high security concept provided by DNA codes can be generated using the random control of coupling powers. The advantage is that the information data can be high secured in the transmission lines in the optical wireless link, where the nonlinear penalty of light traveling in the device is beneficial.