scan

Med

a. the examination of a part of the body by means of a scanner

b. the image produced by a scanner

Collins Discovery Encyclopedia, 1st edition © HarperCollins Publishers 2005

scan

[skan]

(computer science)

To examine information, following a systematic, predetermined sequence, for some particular purpose.

(electronics)

The motion, usually periodic, given to the major lobe of an antenna; the process of directing the radio-frequency beam successively over all points in a given region of space.

(engineering)

To examine an area, a region in space, or a portion of the radio spectrum point by point in an ordered sequence; for example, conversion of a scene or image to an electric signal or use of radar to monitor an airspace for detection, navigation, or traffic control purposes.

One complete circular, up-and-down, or left-to-right sweep of the radar, light, or other beam or device used in making a scan.

scan

Two of the techniques for scanning primary flight instruments.

Scanning by lobe comparison.

i. To search the sky for any hostile aircraft. The area of the scan for a typical two-aircraft formation is indicated in the illustration. In flight, the term means “Search the sector indicated and report any contacts.”
ii. To make a sweep of selected flight instruments or an external scene with the eyes.
iii. The path periodically followed by a radiation beam. See helical scan and conical scanning.
iv. The motion of an electronic beam through space looking for a target. Scanning is carried out by the motion of the antenna or by lobe switching.

SCAN

(1)

["A Parallel Implementation of the SCAN Language", N.G. Bourbakis, Comp Langs 14(4):239-254 (1989)].

SCAN

(2)

A real-time language from DEC.

scan

(3)

(computer peripheral) See scanner.

scan

(4)

(circuit design) See scan design.

scan

(5)

(functional programming) See scanl, scanr.

scan

(storage, algorithm)

An algorithm for scheduling multiple accesses to a disk. A number of requests are ordered according to the data's position on the storage device. This reduces the disk arm movement to one "scan" or sweep across the whole disk in the worst case. The serivce time can be estimated from the disk's track-to-track seek time, maximum seek time (one scan), and maximum rotational latency.

Scan-EDF is a variation on this.

This article is provided by FOLDOC - Free Online Dictionary of Computing (foldoc.org)

scan

(1) To make an electronic comparison of a signal, pixel or data structure as described in the following definitions.

(2) In optical technologies, to read a printed form a line at a time in order to convert images into bitmapped representations or convert characters into text. See OCR.

(3) In video, to move across a picture frame a line at a time, either to detect the image in an analog or digital camera, or to refresh a CRT display.

(4) To search a data file sequentially for specific content.

(5) To search an executable file for a particular pattern. See antivirus program.

(6) To sequentially search for peripheral devices attached to the computer.

Copyright © 1981-2025 by The Computer Language Company Inc. All Rights reserved. THIS DEFINITION IS FOR PERSONAL USE ONLY. All other reproduction is strictly prohibited without permission from the publisher.

Mentioned in

References in periodicals archive

(2) Able to scan precious books or delicate documents easily

Fujitsu Launches ScanSnap SV600: Digitize Entire Books and Newspapers with Ease

Electro Scan products are designed in accordance with ASTM Standard 2550-06 to assess non-conductive pipe materials (e.g.

WEF names Electro Scan 'best Innovative Technology'

One challenge is that there is still debate within the medical community about just how much long term cancer risk the scans carry, she said.

Many people unaware of radiation risk from CT scans

The positives of aerial photographs were scanned applying professional photogrammetric scanner Vexell Ultra Scan and non- professional scanner Microtec ScanMaker8700 employing the format smaller than A3.

Scanning aerial photos using a non-professional scanner

Last night Dr Mark Pearce, the lead researcher at Newcastle University, said the scans were a "life-saving tool", but called for "better justification" for the use of the equipment.

CT scan threat exposed; But the absolute risk is still small, insist researchers

Secondly, cutting GP access to scans wastes time, in which the cancer can grow and spread.

No price on scans

The patients had undergone PET scans before their deaths, and their diagnoses were confirmed by autopsy.

PET scans have high error rate in the diagnosis of non-alzheimer's dementia

"In the more the distant future, once it becomes possible to put all of this processing on one chip and then put that in a iPad or iPod, one could scan just using that chip.

Speedy scanner re-writes book on publishing technology

"We have been told there are hardly any sonographers available because of a change in provider and that scans are being delayed.

Hospital scan delay for mothers; Pregnant women face 23rd week wait for ultrasound Hospital says clinical care not affected

The success of boundary scan testing depends directly upon the implementation of test structures in ICs.

10 boundary scan tips optimize test coverage

Single test strategies are often insufficient, leading to the array of test solutions we see today: ICT, MDA, AOI, AXI, AOXI, benchtop, bare board, on-board, flying probe, vectorless test and boundary scan. The earlier a fault is detected, the cheaper it is to repair.

The boundary scan buzz at Apex: new products are leveraging existing technologies - and receiving much broader adoption

The scanner uses software capable of creating a solid model from a casting scan and comparing it to the casting model supplied by the customer.

Grede-Iron Mountain gains edge with 3-D scanning