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Chapter 12 
AUTOMATIC IDENTIFICATION AND DATA CAPTURE 
REVIEW QUESTIONS 
12.1 What is automatic identification and data capture? 
Answer: The definition given in the text is the following: Automatic identification and data capture (AIDC) 
refers to the technologies that provide direct entry of data into a computer or other microprocessor controlled 
system without using a keyboard. 
12.2 What are the drawbacks of manual collection and entry of data? 
Answer: Three drawbacks are identified in the text: (1) Errors. Errors occur in both data collection and 
keyboard entry of the data when accomplished manually. (2) Time factor. Manual methods are inherently 
more time consuming than automated methods. Also, when manual methods are used, there is a time delay 
between when the activities and events occur and when the data on status are entered into the computer. (3) 
Labor cost. The full-time attention of human workers is required in manual data collection and entry, with the 
associated labor cost. 
12.3 What are the three principal components in automatic identification technologies? 
Answer: The three components given in the text are (1) Data encoder. The data are translated into a machine-
readable code. A label or tag containing the encoded data is attached to the item that is to be later identified. 
(2) Machine reader or scanner. This device reads the encoded data, converting them to alternative form, 
usually an electrical analog signal. (3) Data decoder. This component transforms the electrical signal into 
digital data and finally back into the original alphanumeric characters. 
12.4 Name four of the six categories of AIDC technologies that are identified in the text. 
Answer: The six categories of AIDC technologies identified in the text are (1) optical, such as bar codes and 
optical character recognition, (2) electromagnetic, such as RFID, (3) magnetic, used in plastic credit cards, (4) 
smart cards, which are imbedded with microchips capable of containing large amounts of data, (5) touch 
techniques, such as touch screens, and (6) biometric, such as voice recognition and fingerprint analysis. 
12.5 Name five common applications of AIDC technologies in production and distribution? 
Answer: The applications listed in the text are (1) receiving, (2) shipping, (3) order picking, (4) finished goods 
storage, (5) manufacturing processing, (6) work-in-process storage, (7) assembly, and (8) sortation. 
12.6 There are two forms of linear bar codes. Name them, and indicate what the difference is. 
Answer: The two forms of linear bar codes are (a) width-modulated, in which the symbol consists of bars and 
spaces of varying width; and (b) height-modulated, in which the symbol consists of evenly spaced bars of 
varying height. 
12.7 What was the major industry to first use the Universal Product Code (UPC)? 
Answer: The major industry to first use the Universal Product Code was the grocery industry, starting in 1973. 
12.8 What are the two basic types of two-dimensional bar codes? 
Answer: The two basic types of two-dimensional bar codes are (1) stacked bar codes and (2) matrix 
symbologies. 
12.9 What does RFID stand for? 
Answer: RFID stands for radio frequency identification. 
12.10 What is a transponder in RFID? 
Answer: The RFID identification tag is a transponder. A transponder is defined as a device that emits a signal 
of its own when it receives a signal from an external source. 
12.11 What is the difference between a passive tag and an active tag? 
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Answer: A passive tag has no internal power source; it derives its electrical power for transmitting a signal 
from radio waves generated by the reader when in close proximity. An active tag includes its own battery 
power packs. 
12.12 What are the relative advantages of RFID over bar codes? 
Answer: The relative advantages of RFID over bar codes are (1) read-write capability, (2) large storage capacity, 
(3) line-of sight reading is not required, (4) not susceptible to dirt or scratching that would destroy the label, and 
(5) the tags can be reused. 
12.13 What are the relative advantages of bar codes over RFID? 
Answer: The relative advantages of bar codes over RFID are (1) lower cost and (2) the technology is widely 
available. 
12.14 What are the reasons why magnetic stripes are not widely used in factory floor operations? 
Answer: Three reasons are given in the text: (1) The magnetic stripe must be in contact with the scanning 
equipment for reading to be accomplished, (2) unavailability of convenient shop floor encoding methods to 
write data into the stripe, and (3) the magnetic stripe labels are more expensive than bar code labels. 
12.15 What is the advantage of optical character recognition technology over bar code technology? 
Answer: The advantage is that OCR symbols can be read by humans, whereas bar codes cannot. 
12.16 What is the principal application of machine vision in industry? 
Answer: The principal application of machine vision is automated inspection.