Transmission of data

The various parts of a computer have different functions to deal with peripherals (the viewing screen, the mouse, the keyboard, and inputs and outputs for transmission of data), and all of these... 

At the lowest level, the aetwork is the physical medium that connects the various pieces of equipmeat. This can be copper wire, often known as Ethernet, or optical fiber, ie, fiber-distributed data iaterface (EDDI). Networks allow transmission of data at nominal speeds of 10 to 100 megabits per second, depending on the physical medium used. 

The first transmission of data during drilling using mud pulses was commercialized by B.J. Hughes Inc. in 1965 under the name of teledrift and teleorienter. Both tools are purely mechanical. A general sketch of principle is given in Figure 4-239. The tool is now operated by Teledrift Inc. 

The transmission of data between an ADC or DAC and a computer is usually accomplished by sending one byte at a time along a multiway ribbon cable external bus). The IEEE 488 standard bus has been widely used for this purpose, but other buses are also used. As all bits are handled simultaneously this is known as parallel I/O transmission, the data entering or leaving the computer via a parallel port or by direct connection to the computer s internal bus. Alternatively, one bit at a time can be transmitted along a single line serial I/O transmission). Data enter or leave the computer via a serial port, usually an RS-232C. Serial I/O ports are used for... 

Wireless data communications devices are used to enable transmission of data between computer systems and/or between a SCADA server and its sensing devices, without individual components being physically linked together via wires or cables. In industrial chemical processing systems, these devices are often used to link remote monitoring stations (i.e., SCADA components) or portable computers (i.e., laptops) to computer networks without using physical wiring connections. 

Serial output ports (RS-232) are usually provided for serial transmission of data— usually in ASCII code as previously shown in Fig. 5. 

High transmission rates can be achieved, if necessary, over the relatively short distances required in a process plant. The PCM equivalent of the 4-20 mA analog transmission system shown in Fig. 6.1 can operate at up to 9,600 baud for distances up to 3000 m. The standard RS-232C transmission link is limited to about 15 m at rates up to 20,000 baud. Higher speed interfaces (such as versions of the IEEE-488 connection) used for computer control systems can handle up to 20,000 bytes/s (which for an 8-bit system is about 1.6 x 105 baud). However, in this case, the distance between devices is limited to about 2 m(4). The more recent RS-422A standard allows the transmission of data rates of 107 baud over distances not exceeding 16.4 m and 105 baud over distances not exceeding 1220 m(9S). 

Telemetry. Telemetering in a broad sense involves the transmission of data by any means from a remote and usually inaccessible point to... 

Telemetry system. Telemetry involves the transmission of data from a remote location. The typical implant telemetered data might be the confirmation of the parameters that have been commanded into it, the battery voltage, and the rate of infusing medication both in real time and as stored data. 

Paralleling the growth and developments in the storage and transmission of data by electronic means and the ready availability of personal computers, the way in which information is accessed by chemist has undergone a revolutionary change in the last decade. 

Terminals tied to a computer through RS232C or 20 mA connections are an example of loosely coupled devices. The serial ASCII transmission of data is adequate for applications where dynamics or animation are not a factor (the VT125 and GIGI can be used to a only very limited extent here). This approach has been used in both classes of equipment, our own terminals for example in raster work and Tektronix or IMLAC terminals in vector systems. 

If a result is not received or accessed, it wiU not contribute to an improved outcome. In a systematic study, Kilpatrick and Holding found when they introduced an electronic transmission of data to the emergency department and admissions unit that a notable number of results were never accessed. 

For all transfer modes, the transmission of data within a small number of large packets is the most efficient method. 

One further component has to be taken into consideration, when dealing with computerised systems, namely the nature and extent of the communication system between several computers or between computers and peripheral components. It has to be recognised that all communication links, on whatever level, are potential sources of error, and faulty transmission of data may result in their loss or corruption. This is true of personal communication links, e.g. between Study Director and Principal Investigator, but in the case of communication links between and within computer systems the problem may appear... 

Final Comment. The advent of the information and technology age requires quick and reliable transmission of data and information. Methods such as check digit schemes ensure that this is done confidentially and without error. Today s computer-reliant society uses the material developed in this book on a daily basis in all walks of life. This is illustrated by the simple procedure of sending a credit card number over the Internet. Not only do credit card numbers use the IBM check digit scheme presented in Chapter 3. but the RSA public key cryptography system is used to send the number from the buyer, via the Internet, to the merchant. 

Most implantable systems for neuromuscular application consist of an external and an implanted component. Between the two, an inductive radio-frequency link is established, consisting of two tightly coupled resonant coils. The link allows transmission of power and information, through the skin, from the external device to the implanted pulse generator. In more advanced systems, a back-telemetry link is also established, allowing transmission of data outwards, from the implanted to the external component. 

The BMS ensures transmission of data to a host computer or an external device. There the data can be stored or plotted in a graphical user interface. 

Wireless connection to sensors and transmission of data from an ambulance... 

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