An optimal receiver using a time-dependent adaptive filter

The optimal time-dependent receiver (OTDR) is presented and its performance is compared to that of the matched filter receiver. The OTDR, a time-dependent adaptive filter, is shown through simulation to be superior to the matched filter for signals corrupted by cyclostationary interference because it exploits statistical periodicities of the interference     

A simple alternative to neural network control scheme for robotmanipulators

Recent research results have shown that neural network techniques are effective in compensating highly nonlinear uncertainties in the robot model where computed torque method is used for robot motion control. One excellent work was reported by Ishiguro et. al. (1992). The purpose of this note is to present a simple alternate solution to the same control problem which does not require the use of a neural network. The solution is based on the disturbance rejection technique developed by Hsia (1989-92). Computer simulations show that the alternate control method works better     

Complexity reduction method for ultrasound imaging enhancement in tetrolet transform domain

The Journal of Supercomputing - Medical ultrasound images are often very obscure due to the capture devices used. As medical ultrasound images can provide information regarding potential...     

A cost- and energy-efficient embedded system design based on instruction execution frequencies

In this paper, an embedded system that takes into account the frequency of the executed instructions to reduce memory space and save energy consumption is proposed. The object codes are split into the frequently executed instructions and the infrequently executed instructions (INFIs) by analyzing the trace files of applications. To reduce the use of memory space, the dictionary-based method is used to compress INFIs. To take into account energy consumption, the top-executed instructions are selected to encode as shorter codewords and wrapped into a pseudo instruction. When a pseudo instruction that contains several codewords is fetched, it can be decompressed to several continuous instructions to reduce the number of memory accesses. In addition, to further reduce energy consumption, a multiple reference table design is proposed to make a pseudo instruction contain more encoded codewords by shortening the length of an encoded instruction. From the simulation results, the proposed design that uses one 256-instruction reference table reduces the energy consumption about 50.4% compared to the dictionary-based method. In addition, to show the improvement of energy consumption for the proposed multiple reference table method over that using one reference table, we also show the simulation results of a design with two 256-instruction reference tables which shows less energy use than a design with one 512-instruction reference table by 12.1%.     

Glycidyl-terminated polyurethane modified epoxy resins: Mechanical properties,adhesion properties,and morphology

Glycidol was used to convert the isocyanate-terminated polyurethane prepolymer to glycidyl-terminated polyurethane prepolymer. The modified polyurethane not only offers some distinct advantages over the commercial polyurethane prepolymer, but also enhances the properties of the epoxy resins. The glycidyl-terminated polyurethane modified epoxy resin proved to be superior to conventional epoxy resins in improving impact strength, fracture energy, and adhesion properties. The compatibility of the compounds in this glycidyl-terminated PU/epoxy system was investigated using different preparation procedures. It was found that the synthesized glycidyl-terminated polyurethane prereacted with curing agents, exhibited a lesser degree of phase separation, and can influence the mechanical properties of polymer blends. The results coincide with the phenomena observed in dynamic mechanical analysis and scanning election microscopy. © 1994 John Wiley & Sons, Inc.     

Resistance of Fomblin Z-Type Lubricants to Lewis Acid-Catalyzed Decomposition: Effect of the Chemical and Electronic Structure of End-Groups

In the present paper, the effect of the chemical and electronic structure of the Fomblin Z-type lubricant end-group on the Lewis acid-catalyzed decomposition is studied by both Thermogravimetric Analysis (TGA) and Density Functional Theory (DFT) molecular orbital calculations. TGA results of the mixture of Z-type lubricants and ZrO ₂ show that the structure of the end-groups significantly affects the thermal stability of the lubricants in the presence of a Lewis acid. The DFT calculation results suggest that the reactivity of the end-groups and thus the resistance of various lubricants to Lewis acid-catalyzed decomposition are affected by the lubricant molecular orbital structure.     

Contact-free hand geometry-based identification system

This paper presents an approach for personal identification using hand geometrical features, in which the infrared illumination device is employed to improve the usability of this hand recognition system. In the proposed system, prospective users can place their hand freely in front of the camera without any pegs or templates. Moreover, the proposed system can be widely used under dark environment and complex background scenarios. To achieve better detection accuracy, in total 13 important points are detected from a palm image, and 34 features calculated from these points are used to further recognition. Experimental results demonstrate that the averaged Correct Identification Rate (CIR) is 96.23% and averaged False Accept Rate (FAR) is 1.85%. These results prove that the proposed contact-free system can be considered as an effective identity verification system for practical applications.     

Novel fast block motion estimation using diamond‐arc‐hexagon search patterns

Abstract

This work presents a novel block motion estimation (ME) approach, diamond‐arc‐hexagon search (DAHS), which uses diamond, arc, and hexagon search patterns to accomplish the fast searching process. According to the characteristic of the center‐based motion vector distribution for the real‐world video sequence, DAHS employs a small diamond pattern extended hexagon search to refine the central area search. Furthermore for estimation in large motion situations, the strategy of the large diamond‐to‐arc search can preserve good performance. Experimental results indicate that DAHS is suitable for both (quasi‐) stationary and large motion searches. DAHS outperforms the efficient three‐step (E3SS) and hexagon‐based search (HEXBS) in prediction quality, and improves the searching speed about 9% compared to E3SS. The proposed algorithm was tested using several sequences and delivered excellent performance in search speed and prediction of video quality. The DAHS can be applied to real‐time video processes, such as H.264/MPEG‐4 advanced video coding (AVC) and scalable video coding (SVC).