To prevent interference problems due to existing nearby communication systems within an ultrawideband (UWB) operating frequency, the significance of an efficient band-notched design is increased. Here, the band-notches are realized by adding independent controllable strips in terms of the notch frequency and the width of the band-notches to the fork shape of the UWB antenna. The size of the flat type band-notched UWB antenna is etched on 24 times 36 mm2 substrate. Two novel antennas are presented. One antenna is designed for single band-notch with a separated strip to cover the 5.15-5.825 GHz band. The second antenna is designed for dual band-notches using two separated strips to cover the 5.15-5.35 GHz band and 5.725-5.825 GHz band. The simulation and measurement show that the proposed antenna achieves a wide bandwidth from 3 to 12 GHz with the dual band-notches successfully.

UWB Antenna With Single or Dual Band-Notches for Lower WLAN Band and Upper WLAN Band

https://isda05.softcomputing.net/insci.pdf

Time-series forecasting using flexible neural tree model

Time-series forecasting is an important research and application area. Much effort has been devoted over the past several decades to develop and improve the time-series forecasting models. This paper introduces a new time-series forecasting model based on the flexible neural tree (FNT). The FNT model is generated initially as a flexible multi-layer feed-forward neural network and evolved using an evolutionary procedure. Very often it is a difficult task to select the proper input variables or time-lags for constructing a time-series model. Our research demonstrates that the FNT model is capable of handing the task automatically. The performance and effectiveness of the proposed method are evaluated using time series prediction problems and compared with those of related methods.

In this study, a sliding mode control system with a proportional+integral+derivative (PID) sliding surface is adopted to control the speed of an electromechanical plant. A robust sliding mode controller is derived so that the actual trajectory tracks the desired trajectory despite uncertainty, nonlinear dynamics, and external disturbances. The proposed sliding mode controller is chosen to ensure the stability of overall dynamics during the reaching phase and sliding phase. The stability of the system is guaranteed in the sense of the Lyapunov stability theorem. The chattering problem is overcome using a hyperbolic function for the sliding surface. Experimental results that are compared with the results of conventional PID verify that the proposed sliding mode controller can achieve favorable tracking performance, and it is robust with regard to uncertainties and disturbances.

Sliding mode control with PID sliding surface and experimental application to an electromechanical plant.

Nonlinear modeling and identification of a DC motor for bidirectional operation with real time experiments

Neural adaptive tracking control of a DC motor

For liquid phase deposition (LPD) at room temperature (∼40°C) of silicon dioxide (SiO 2 ) on gallium arsenide (GaAs) substrate, this study correlates growth solution concentrations with resultant film quality. This LPD process pretreats the GaAs substrate with ammonia solution kept at pH=11–12, thereby generating OH radicals on the GaAs surface which enhance SiO 2 deposition. It is found that growth conditions such as low hydrofluosilic acid concentration, proper boric acid concentration, and low growth rate play important roles in optimizing deposited film quality. When LPD-SiO 2 /GaAs grown at optimum conditions is used to fabricate a metal-oxide-semiconductor field effect transistor, the transconductance, g m , is about 68, the drain current, I DS , is 10 mA for gate oxide thickness=20 nm and W / L =40/2. LPD-SiO 2 /GaAs grown at the proposed conditions equals or exceeds the quality of competing techniques, with a process that proceeds rapidly at room temperature and pressure, with inexpensive equipment.

Quality optimization of liquid phase deposition SiO2 films on gallium arsenide

Hybrid MATLAB and LabVIEW with neural network to implement a SCADA system of AC servo motor

SCADA system of DC motor with implementation of fuzzy logic controller on neural network

A novel compact 5.2 GHz notched ultra-wideband (UWB) CPW-fed monopole antenna using dual reverse split trapezoid slots which has small area of (16 × 17 mm2) is proposed. The designed antenna operates over 3–11 GHz for VSWR ≤ 2 including the WLAN band notched at the vicinity of 5.2 GHz. The dual reverse split trapezoid slots are employed effectively for notching unwanted frequency band such as that for WLAN service, since it can be implemented with a small dimension and in a high Q operation similarly to the conventional strip-type dual reverse split ring resonator (SRR). Based on the simulated and measured results, a band notched UWB antenna using dual reverse split trapezoid slots is very effective in rejecting unwanted frequency in terms of its selectivity. Good monopole-like radiation patterns and antenna gains have also been obtained. © 2008 Wiley Periodicals, Inc. Microwave Opt Technol Lett 50: 652–655, 2008; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.23157

http://cooshow.web.ntut.edu.tw/ezfiles/0/academic/12/academic_51034_5793359_97903.pdf

Jui-Hong Horng

Papers

Neural adaptive tracking control of a DC motor

Quality optimization of liquid phase deposition SiO2 films on gallium arsenide

Hybrid MATLAB and LabVIEW with neural network to implement a SCADA system of AC servo motor

SCADA system of DC motor with implementation of fuzzy logic controller on neural network

Miniaturized 5.2 GHz notched UWB CPW‐FED antenna using dual reverse split trapezoid slots