Computer links

However, optical fiber communications are not useful only for long-distance communication links. Fiber-optic data links are also used in a variety of short-distance systems, for example in computer—computer links and for internal communications on ships and aircraft. Figure 16 shows some possible appHcations for fiber-optic communications, with respect to length and bit rate. The common carrier appHcations, like telephone links. He to the upper right of the dashed line labeled 100 MHzkm. However, a wide variety of other lower performance appHcations, illustrated to the lower left of the dashed line, are in use or under development. 

If data gathering is also computer-linked, then the problem is to check out the correctness of the program. Hand calculation of one rated point for How head, efficiency, and horsepower will serve as verification. 

In Figure 0-5, the area under each peak is proportional to the quantity of compound passing through the detector. The best way to measure area is with a computer that receives output from the chromatography detector. Denby and Scott did not have a computer linked to their chromatograph, so they measured the height of each peak instead. 

This method of luminescence quantum yield measurement against a standard emitter is simple and easy to implement with computer-linked fluorimeters, in particular for the integration of the spectra. Its accuracy should however not be over-rated. It is, in the best cases, of the order of 5% (and often far worse). It remains at this time the most widely used technique in photophysics. 

Millar, B and Broughton, R. A Preliminary PK Experiment with a Novel Computer-Linked High-Speed Random Number Generator. In J. Morris, W. Roll, and R. Morris (eds.). Research in Parapsychology, 1975. Metuchen, N.J. Scarecrow Press, 1976, pp. 83-84. 

When considering automating the sample preparation steps and interfacing with chromatographic systems, laboratory robotics has been the method of choice. A laboratory robotics system has a robotic arm and controller, a computer linked to a controller or connected directly to the robotic arm, and application peripherals for performing specific functions in the application process. 

Commercial data systems are now available for all the principal GC-MS instruments although a number of independent centres have developed their own systems to suit individual requirements [44]. These range from low cost off-line systems to dedicated mini computers linked to time-shared central computers. Many of these systems are in advance of commercial packages but the different capabilities of their configurations are outside the scope of this article. (For a review of computerised data acquisition and handling see [45]). However it is useful to consider some of the hardware components and requirements of a small on-line computer system (Figure 1.8) for low resolution GC-MS work. 

This BLAST Quickstart chapter illustrates the use of the principal BLAST programs to solve problems that arise in the analysis of protein and nucleotide sequences. Each section provides a succinct description of a protocol with two problems that serve as practical examples. Relevant theory is given when it affects the selection of a search strategy or search parameter, however, the emphasis is on the procedure itself. The sections follow closely the structure of the BLAST QuickStart Mini-Course found at www.ncbi.nlm.nih.gov/Class/minicourses. The BLAST QuickStart is one of 10 2-h format Mini-Courses offered by NCBI on campus at the National Institutes of Health and at locations around the country to over 4000 students a year. The courses use a paired problems approach in which the first of two similar problems or problem sets is solved by the instructor during the first hour on a computer linked to a projection system, while the students watch in the second hour, the students tackle the second problem, or set of problems at their... 

Scientists use a variety of tools and technologies to perform tests, collect and display data, and analyze relationships. Examples of commonly used tools include computer-linked probes, spreadsheets, and graphing calculators. 

Scientists use computer-linked probes to measure various environmental factors including temperature, dissolved oxygen, pH, ionic concentration, and pressure. The advantage of computer-linked probes, as compared to more traditional observational tools, is that the probes automatically gather data and present it in an accessible format. This property of computer-linked probes eliminates the need for constant human observation and manipulation. 

Large libraries have been replaced by small massive digital memory storage units governed by a central computer linked to a vast terminal network. These are the so-called data banks or data bases , a homogeneous collection of information Items stored on magnetic media and accessible by computers. They differ from other Information media In three essential aspects, namely ... 

Takahashi, T., and Kobatake, Y. (1982) Computer-linked automated method for measurement of the reversal frequency in phototaxis of Elalobacterium halobium. Cell Struct. Eunct. 7,183-192. 

The behavior can be videotaped or scored by one or two observers, or automated versions are computer linked for data acquisition, storage, and retrieval (Fig. 2). 

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