Data: Instrumentation Building a Smart Laboratory 2015
Data: Instrumentation
Tis chapter will look at analogue and digital data and how the conversion of analogue signals into a digital format is at the heart of laboratory informatics. It will also consider the different classes of instruments and computerised instrument systems to be found in laboratories and the role they play in computerised experiments and sample processing – and the steady progress towards all-electronic laboratories. However, the choice of best-of-breed laboratory instruments and instrument systems can present challenges when it comes to getting everything to work together in a seamless way. Te final part of this chapter will look at the issue of standard data interchange formats, the extent of the challenge, and some of the initiatives to address them.
Collecting data and observations has been part of laboratory work for centuries. One of the major changes is how fast we can acquire the data, and our ability to work with what we’ve collected. Trough the 19th century, data collection rates were a few data points per minute, it took time for the analogue- to-digital converter (the observer) to make a measurement and record it. In the 20th century, analogue electronics had advanced to the
10
point where signals from experiments could be recorded at a high rate on strip chart recorders connected to chromatographs, spectrometers, and seismographs. Electro-physiological measurements could record data spewing out paper at a couple of feet per second. Making quantitative measurements was another matter, limited by the experimenter’s ability to process the instrument’s output manually. Te development of electronic analogue-
to-digital converters (A/D) connected to computers changed all that: data acquisition provided the measurements in numerical form, plus the ability to process it. Tat simple step is the basis of the modern laboratory’s ability to handle everything from complex physics experiments, integrated hyphenated analytical techniques, high-throughput screening in life sciences, and automated sample preparation, with almost every piece of lab equipment now fitted with a computer chip.
Analogue vs. digital data
A casual glance around a lab at all the computers and devices with chips in them might raise a question about the relevance of discussions about analogue data. With the
possible exception of quantum effects, analogue data acquisition is highly relevant – there are no naturally occurring digital signals in the real world and every instrument that displays or works with digital data has an A/D in it. Balances, pH meters, thermometers and melting point equipment all follow the same basic model where time-critical
“ Collecting data and observations has been part of laboratory work for centuries”
measurements are not a factor (see Figure 2). In addition, a lot of experimental work isn’t supported by commercial products and has to be carried out with equipment developed by researchers. Tis may also include digital- to-analogue (D/A) converters to control equipment and devices. Tere is an important characteristic that
distinguishes the digital and analogue worlds: signals in the real world are continuous, whereas digital values occur in discrete steps. A microwave oven allows heating times to be set only in whole seconds, while fractions of a second exist in the real world. Consequently,
www.scientific-computing.com/BASL2015
Sergey Nivens/
Shutterstock.com
Page 1 |
Page 2 |
Page 3 |
Page 4 |
Page 5 |
Page 6 |
Page 7 |
Page 8 |
Page 9 |
Page 10 |
Page 11 |
Page 12 |
Page 13 |
Page 14 |
Page 15 |
Page 16 |
Page 17 |
Page 18 |
Page 19 |
Page 20 |
Page 21 |
Page 22 |
Page 23 |
Page 24 |
Page 25 |
Page 26 |
Page 27 |
Page 28 |
Page 29 |
Page 30 |
Page 31 |
Page 32 |
Page 33 |
Page 34 |
Page 35 |
Page 36 |
Page 37 |
Page 38 |
Page 39 |
Page 40 |
Page 41 |
Page 42 |
Page 43 |
Page 44