It 345 final test review Benefit of auto id Provide visibility Less waste Reducing resources Better customer service Just in time manufacturing Different types of aids technologies-list them Barbados Biometrics Card technologies Optical technologies Radio frequency identification Evaluate transit tickets- what technology is best (refold, tokens, smart cards) Aids technologies are complementary or not? Linear Barbados What is a linear barded?
A linear barded encodes data on the x axis (bottom) so it doesn’t matter where on the y axis the bar code is scanned, the data will always be the same describe an element An element is either a bar or a space Narrowest element is a module -x dimension The width of a module is called an X dimension vertical redundancy Linear barded encodes data in the x axis. Therefore the data is the same regardless of where on the y axis the data is scanned. This is called vertical redundancy. Understand relationship between modulus elements and x dimension The width of a module is called an X dimension…
Measured in mils… XX is wide…. X is narrow Width of a module is an x dimension understand the inter character gap Interchanger spacing is between the characters Ill (gap) Ill (gap) ill inter character gap serves as a break between the characters of a discrete encoded bar code… The width of the gaps should not be more than xx dimensions understand the relationship of barded and bar code data density and continuous, discrete Barbados.. One has something that the other doesn’t Discrete barded for example (code 39) has a very limited data density which is a drawback..
Continuous has greater data density -determination bar. What type of symbol has one of these? PUC? Is there a relationship between discrete, width, delta continuous encoding?? Which symbol is that? Continuous 4 widths discrete 2 widths PDF PDF 417 can withstand high levels to destruction at times Relationship between error detection and code words and destruction Higher the error detection more code words and destruction it can withstand Rule of thumb- certain amount of Max characters you can encode in a linear barded.. Has to deal with length Data density is the amount of characters you can encode in a barded.. Harassers re inch Code 128 high density ? greater data density ABACI 230 Less data density A B CLC 230 – # of start/stop characters for code 128 code 128 3 start characters 1 stop character Limitations of linear bar code check digit Describe the differences between stacked and linear bar code Stacked addresses many limitations of linear bar code More data capacity Able to store information Can be connected together Error correction and detection Know the maximum # of rows and columns in a PDF 417 COLUMNS- 30 maximum ROWS-90 is maximum
Understand which matrix code is used in package sending (Amazon) Maxi code Which barded is used mostly Which matrix barded was used in the automotive sector now appears pre dominantly in the mobile sector Cry code itty CRY code, maxi code, data matrix trot a line up CRY code- 3 squares in the corner Maxi code- bulls eye in the middle Data matrix- 1 solid border 1 broken border Diagram that relates to optical throw, depth of field, operating range, focal length, SCANNING TECHNOLOGIES powerboat Calculate operating range (A+B=C) Operating range = Optical throw + depth of field
Barded table 5 7 1 5 range size, scanning technologies (similar to slide) 7. 5 mil scans 2-10 inch example question will 7. 5 mil scan 11 inch away? Answer: no Which wavelength red reflects at? 660-670 NanoMeter Omni directional bar code scanner Where is it normally found? Grocery store, retail Know how an imagery works (scanner in lab) USE LED light to illuminate the barded. Similar to digital camera. Decoder software locates barded in the image and then uses image-processing algorithms to decode the barded Tell the relationship between bars and spaces with respect to reflectance
Dark bars absorb and white spaces reflect light in Barbados What reflects and what absorbs? Scanning technologies module – Bar code scanner spec sheet- review this Performance characteristics- most important Depth of field Physical characteristics Selecting a particular scanner,AAA Grocery— PUC/MEAN Barbados read by OMNI DIRECTIONAL SCANNER Logistics- VEHICLE MOUNTED SCANNERS verification module- there are several wavelength scanner analysis Recreate the barded symbol analysis sheet 25 min 11/14 lecture Quiet zones Global threshold above are spaces below are bars
Determine wavelength, # of times a bar code needs to be verified to be recorded, Should be able to tell the global threshold Usually colored Line, through the middle of the results on the graph Should be able to tell the grade decidability on the scan profile Should be able to tell if the message format passed If it fails any of the quiet zone or pattern test it fails Should be able to report the values from the specification sheet Calculate symbol contrast, print contrast signal, x mom Print Contrast signals, signal contrast give conflicting results- is that true
Measurement of ratio of repetitiveness between bars and spaces of a Sybil Symbol contrast = RSI- R b Difference between the highest and the lowest reflectance value Question 5 Tell why it is true or not What does quiet zone failing mean If the quiet zone fails the barded may be unreadable or only readable in one direction due to not being of the right size. The barded fails Modulation issue- how would you fix it Make them uniform What happens if it is fixed? What problems still exist once fixed in certain ways Affect the global threshold
Be able to tell the symbol from the scan profile Identify the wavelength of the scanner from the verification sheet Identify the single scan grade from the verification sheet Lowest grade for any of the 9 attributes Be able to determine what the global threshold pass is Know the effect that happens if the global threshold doesn’t pass Know the number of scans that make an ANSI grade.. What is the grade? 10 scans Grade, Aperture, wavelength Overall symbol grade 60 We will be Given Barbados, what are the problems? Questions on the projects 1 question per each project