The sievert unit, in the context of CT scans, does not correspond to the actual radiation dose that the scanned body part absorbs but to another radiation dose of another scenario, the whole body absorbing the other radiation dose and the other radiation dose being of a magnitude, estimated to have the same probability to induce cancer as the CT scan. Since the introduction of the USB standard, it is the interface most commonly used. Pushkar, K.S. [10] Others dispute this estimate,[11] as there is no consensus that the low levels of radiation used in CT scans cause damage. Water has an attenuation of 0 Hounsfield units (HU), while air is −1,000 HU, cancellous bone is typically +400 HU, and cranial bone can reach 2,000 HU or more (os temporale) and can cause artifacts. Non-contact planetary scanners essentially photograph delicate books and documents. Types of fingerprint scanners There are four types of fingerprint scanner: the optical scanner, the capacitance scanner, the ultrasonic scanner, and the thermal scanner. It is commonly used to investigate acute abdominal pain. Many areas of the country now require a more advanced type of scanner (trunking or trunking and digital) to monitor state-of-the-art local, county and/or state radio systems. For the latter, the scanned result is a non-compressed RGB image, which can be transferred to a computer's memory. Multiple models can be constructed from various thresholds, allowing different colors to represent each anatomical component such as bone, muscle, and cartilage. This allows bends in a vessel to be "straightened" so that the entire length can be visualised on one image, or a short series of images. This data is then processed with some proprietary algorithm to correct for different exposure conditions, and sent to the computer via the device's input/output interface (usually USB, previous to which was SCSI or bidirectional parallel port in older units). Infrared cleaning is a technique used to remove the effects of dust and scratches on images scanned from film; many modern scanners incorporate this feature. Compared to the lowest dose x-ray techniques, CT scans can have 100 to 1,000 times higher dose than conventional X-rays. Sibilyev. Following are some examples of impact printers. [62] These incidents are believed to be due to human error.[62]. The API presents a uniform interface to the scanner. A hand scanner may have a small window through which the document being scanned could be viewed. Higher resolution is not always suitable for any given scenario, such as detection of small pulmonary masses. For example, Epson, Minolta, Nikon, Konica Minolta, Microtek, and others use Digital ICE, while Canon uses its own system FARE (Film Automatic Retouching and Enhancement system). Pixel is a two dimensional unit based on the matrix size and the field of view. The density range of negative film is up to 3.6d,[14] while slide film dynamic range is 2.4d. Still, the epitomes of volume rendering models feature a mix of for example coloring[95] and shading[96] in order to create realistic and observable representations. [69][71] Typically, the API is implemented as a dynamically linked library. During the 2010s fingerprint scanners became commonplace on mobile phones. Because of increased susceptibility of fetuses to radiation exposure, the radiation dosage of a CT scan is an important consideration in the choice of medical imaging in pregnancy. CT data sets have a very high dynamic range which must be reduced for display or printing. Image scanners are usually used in conjunction with a computer which controls the scanner and stores scans. The equivalent dose is the effective dose of a case, in which the whole body would actually absorb the same radiation dose, and the sievert unit is used in its report. /O.I. Handheld Scanner: A handheld scanner, as the name suggests, refers to an electronic device that performs the same tasks as that of a flatbed scanner. CT scanning can perform a virtual colonoscopy with greater accuracy and less discomfort for the patient than a traditional colonoscopy. Handheld scanner - scans text and images by dragging the device over the page you want to scan. For evaluation of chronic interstitial processes such as emphysema, and fibrosis, thin sections with high spatial frequency reconstructions are used; often scans are performed both on inspiration and expiration. Typically, in addition to the scanning utility, some type of image-editing application (such as Adobe Photoshop), and optical character recognition (OCR) software are supplied. Most adverse health effects of radiation exposure may be grouped in two general categories: The added lifetime risk of developing cancer by a single abdominal CT of 8 mSv is estimated to be 0.05%, or 1 one in 2,000.[84]. This type of scanner is sometimes called a reflective scanner because it works by shining white light onto the object to be scanned and reading the intensity and color of light that is reflected from it, usually a line at a time. [62] A typical plain film X-ray involves radiation dose of 0.01 to 0.15 mGy, while a typical CT can involve 10–20 mGy for specific organs, and can go up to 80 mGy for certain specialized CT scans. [14] Density range is the space taken up in the 0 to 5 scale, and Dmin and Dmax denote where the least dense and most dense measurements on a negative or positive film. Document scanners have document feeders, usually larger than those sometimes found on copiers or all-purpose scanners. The process of whole-surface-at-once capturing has the benefit of increasing reaction time for the work flow of scanning. For many fragile objects, direct research and observation can be damaging and can degrade the object over time. [62] Those in the nuclear industry in the United States are limited to doses of 50 mSv a year and 100 mSv every 5 years.[62]. Of the above, hypodense (dark) structures can indicate edema and infarction, hyperdense (bright) structures indicate calcifications and haemorrhage and bone trauma can be seen as disjunction in bone windows. While most output is human-readable, bar code printers are an example of an expanded use for printers. Some of the key uses for CT scanning have been flaw detection, failure analysis, metrology, assembly analysis, image-based finite element methods[113] and reverse engineering applications. 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