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The GeForce 256 is the original release in Nvidia's "GeForce" product line.Announced on August 31, 1999 and released on October 11, 1999, the GeForce 256 improves on its predecessor by increasing the number of fixed pixel pipelines, offloading host geometry calculations to a hardware transform and lighting (T&L) engine, and adding hardware motion compensation for MPEG-2 video.
Drawing of CT fan beam and patient in a CT imaging system CT scan of the thorax. The axial slice (right) is the image that corresponds to number 2/33 on the coronal slice (left). Spinning tube, commonly called spiral CT, or helical CT, is an imaging technique in which an entire X-ray tube is spun around the central axis of the area being ...
In conventional CT machines, an X-ray tube and detector are physically rotated behind a circular shroud (see the image above right). An alternative, short lived design, known as electron beam tomography (EBT), used electromagnetic deflection of an electron beam within a very large conical X-ray tube and a stationary array of detectors to achieve very high temporal resolution, for imaging of ...
The first production X-ray CT machine (in fact called the "EMI-Scanner") was limited to making tomographic sections of the brain, but acquired the image data in about 4 minutes (scanning two adjacent slices), and the computation time (using a Data General Nova minicomputer) was about 7 minutes per picture.
The GECOS operating system was developed by General Electric for the 36-bit GE-600 series in 1962–1964; GE released GECOS I (with a prototype 635) in April 1965, GECOS II in November 1965 and GECOS III (with time-sharing) in 1967. [5] It bore a close resemblance architecturally to IBSYS on the IBM 7094 and less to DOS/360 on the IBM System ...
Low-dose high-resolution (1.25 mm) chest CT. HRCT is performed using a conventional CT scanner. However, imaging parameters are chosen so as to maximize spatial resolution: [1] a narrow slice width is used (usually 1–2 mm), a high spatial resolution image reconstruction algorithm is used, field of view is minimized, so as to minimize the size of each pixel, and other scan factors (e.g. focal ...
Coronary CT angiography (CTA or CCTA) is the use of computed tomography (CT) angiography to assess the coronary arteries of the heart.The patient receives an intravenous injection of radiocontrast and then the heart is scanned using a high speed CT scanner, allowing physicians to assess the extent of occlusion in the coronary arteries, usually in order to diagnose coronary artery disease.
Modern SPECT equipment is available with an integrated X-ray CT scanner. As X-ray CT images are an attenuation map of the tissues, this data can be incorporated into the SPECT reconstruction to correct for attenuation. It also provides a precisely registered CT image, which can provide additional anatomical information.