Both light emitting diode (LED) characteristics for illumination and communication simultaneously have made visible communication-orthogonal frequency division multiplexing (VLC-OFDM) a strong competitive to radio (RF). In this juncture, improve signal noise ratio (SNR) coverage contour, the wavelet-OFDM is suggested indoor VLC systems. paper, wavelet VLC-OFDM proposed imaging multiple-input mu...

Ontologies are more and more used in information systems. When the size of data described by ontologies can not be manage in main memory, information system designers have to use specialized databases called semantic databases. As these databases use different architectures, storage layouts and ontology languages, this task is complex. In this paper, we propose a comparison and evaluation of th...

This paper describes a threefold method of testing the performance of an array-based ultrasonic tool for nondestructive testing of spot welds. The tool is described in its capabilities, use, and advantages over existing counterparts. Performance testing is not only described, but results from carrying out the testing are documented as well. The three performance testing methods include the use ...