CAGD-based computer vision

The authors explore the connection between CAGD (computer-aided geometric design) and computer vision. A method for the automatic generation of recognition strategies based on the 3-D geometric properties of shape has been devised and implemented. It uses a novel technique to quantify the following properties of features which compose models used in computer vision: robustness, completeness, consistency, cost, and uniqueness. By utilizing this information, the automatic synthesis of a specialized recognition scheme, called a strategy tree, is accomplished. Strategy trees describe, in a systematic and robust manner, the search process used for recognition and localization of particular objects in the given scene. The consist of selected 3-D features which satisfy system constraints and corroborating evidence subtrees which are used in the formation of hypotheses. Verification techniques, used to substantiate or refute these hypotheses are explored. Experiments utilizing 3-D data are presented     

An advanced electronic load governor for control of microhydroelectric generation

This paper describes the original research and development of an electronic load governor which is microprocessor-based and incorporates three-phase balancing. The combined study and testing of the transient behaviour of the governor indicated the need for an improved control algorithm. The results of the implementation of the advanced algorithm in the control of micro hydroelectric power generation are presented and compared with the original algorithm     

Quadrature Vestigial Sideband (QVSB) Data Transmission

The combined use of quadrature modulation and vestigial sideband filtering is investigated as a means of obtaining a spectrally efficient modulation scheme. The name quadrature vestigial sideband (QVSB) aptly describes the new system, whereby two independent data streams are each VSB modulated into the same passband, but on quadrature related carriers. The inherent interference between the quadrature related channels is shown to be of a controlled form, similar to the intersymbol interference (ISI) in partial response (PR) systems. Techniques suitable for "unwinding" the ISI in PR systems are shown to be also applicable to QVSB. Precoding with bit-by-bit, decoding, nonoptimum and optimum probablistic decoding are investigated. The latter method results in only a 1.2 dBE_{b}/N_{0}degradation, atP_{b} = 10^{-5}, compared to coherent binary phase shift keying (BPSK), although up to a fourfold increase in spectral efficiency can be obtained.