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The DNA sequence of the human genome has been determined. This significant scientific milestone has been a multidisciplinary effort sponsored by both public and private investments. Engineering and computer science contributions have been essential to success, especially with the accelerated schedules of the Human Genome Project. A tutorial summary of the biological and health implications of sequencing the human genome is presented together with examples of how genome data from human and other organisms are already used. Engineering contributions to sequencing are identified as well as predictions of how engineering methods may contribute to the "postsequencing" era of biology.

An efficient method for accurately calculating the center-of-rotation, or projection center, for parallel computed tomography projection data, or sinograms, is described. This method uses all the data in the sinogram to estimate the center by a least-squares technique and requires no previous calibration scan. The method also finds the object's center-of-mass without reconstructing its image. Since the method uses the measured data, it is sensitive to noise in the measurements, but that sensitivity is relatively small compared to other techniques. Examples of its use on simulated and actual data are included. For fan-beam data over 360 degrees , two related methods are described to find the center in the presence or absence of a midline offset. >

It is shown that if sign modulation is applied in both the sample and transform domains to a signal whose dimension is not an integral multiple of four, then a phase error results in the transformed signal. Although this result is inconsequential to radix-two algorithms, it is extremely important to the increasingly popular prime-radix and mixed-radix fast Fourier transform (FFT) algorithms. >