Attached processors

Atomic natural orbitals, use, 18 Attached processors FPS-164, 238-239 IBM hosts, 239 Aufbau principle, 51-52 Axial momentum, conservation of, CVD reactor, 337... 

The use of concurrence or parallelism in chemistry applications is not new. In the 1980s chemistry applications evolved to take advantage of multiple vector registers on vector supercomputers and attached processors by restructuring the software to utilize matrix—vector and matrix—matrix operations. In fact, once the software had been adapted to vector supercomputers, many applications ran faster on serial machines because of improved use of these machines memory hierarchies. The use of asynchronous disk operations (overlapped computation and disk reads or writes) and a few loosely coupled computers and workstations are other concurrency optimizations that were used before the development of current MPP technology. The challenge of the... 

Recently relatively cheap special purpose "attached processors" have become available, and this paper describes an evaluation which is being carried out at Cornell on the applicability of one such processor to large-scale scientific calculations such as the simulations described earlier. The particular machine is a Floating Point Systems 190-L Array Processor (AP). The AP features include ... 

The full cost-recovery rate for the AP-190L at Cornell, based on a three-year amortization schedule, is 40/hour. Since the previous benchmarks have shown that the AP can run at from 1.5-2.5 times the speed of the IBM 370/168, this yields a cost-comparison of about 80 1 in the Cornell environment. It is important to note that this ratio uses the prime-time 370 rates, and can be reduced by a factor of about 0.4 for overnight turnaround. The comparison may also be substantially less favorable to the AP for a partially-subsidized host computer. However, this is still a dramatic demonstration of the potential cost advantage of carrying out large-scale scientific calculations on such an attached processor. 

One-Step Cameras and Processors. The eadiest one-step cameras used roU film and completed processing inside a dark chamber within the camera (9). The first instant color film, Polacolor, was provided in roU film format to fit these cameras. Flat-pack film cameras (Fig. 2), introduced in 1963, permitted the film to be drawn between processing rollers and out of the camera before processing was completed (10). Film holders for instant 10 X 13 cm (4x5 in.) film packets contain retractable rollers that permit the film to be loaded without mpturing the pod (11). For 20 x 25 cm (8 x 10 in.) films, the processing rollers are part of a tabletop processor. The exposed film, contained in a protective black envelope, and a positive sheet with pod attached are inserted into separate slots of a tray that leads into the processor. The film passes through the rollers into a covered compartment within which processing is completed. 

Mathematical models require computation to secure concrete predictions. Successes in relatively simple cases spurs interest in more complex situations. Somewhat specialized computer hardware and software have emerged in response to these demands. Examples are the high-end processors with vector architecture, such as the Cray series, the CDC Cyber 205, and the recently announced IBM 3090 with vector attachment. When a computation can effectively utilize vector architecture, such machines will out-perform even the most powerful conventional scalar machine by a substantial margin. Such performance has given rise to the term supercomputer. ... 

Xeotron also uses a DMD processor to produce arrays in microchannels (Figure 2.6). Standard oligonucleohde phosphoramidite-based S5mthesis is performed. The virtual masking is directed instead toward deprotechon of a pho-tolabile acid. The process is called PGA or photogenerated acid. Once the acid is liberated, the trityl group on the attached base can be removed to allow base extension to occur. Stepwise pelds of 98.5% are reported for the XeoGhip. 

Infrared spectra were recorded on the resist film spun onto a silicon wafer using a JASCO IR-810 spectrometer equipped with a JASCO BC-3 beam condenser or a JASCO A-3 spectrometer. In the measurements on the latter spectrometer an uncoated silicon wafer was placed in the reference beam in order to balance the silicon absorption band. The subtraction between the spectra was carried out on a built-in micro-processor attached to the IR-810 spectrometer, and the resulting difference spectrum was used to detect structural changes in the polymer molecule upon exposure. The subtraction technique was also used to balance the silicon absorption band. 

In screw extruders, as we have seen, the processing takes place in the helical channel formed between the screw and the barrel. In a co-rotating disk processor (CDP), on the other hand, processing takes place in flat doughnut-shaped processing chambers formed by two neighboring disk surfaces, the inner surface of the barrel, the shaft to which the disks are attached, and the channel block attached to the barrel, with very small clearance to the disk surfaces. It thus blocks the channel and separates inlet from outlet, as shown in Fig. 9.44. Processing chambers can be connected in series, parallel, or any other... 

An HgCdTe slice which has been cleaned and polished is anodically selenidized. The slice is then attached with epoxy to a silicon processor chip and MIS detectors are formed similar to the MIS detectors presented in EP-A-0137988 above. 

VAX 11-70 with attached Floating Point Systems Array Processor... 

Ostlund, N. S. "Attached Scientific Processors for Chemical Computations A report to the Chemistry Community", NRCC report (1980). 

As indicated earlier, the operator has several variables under his control to selectively tailor the products. There are two types of selectivity the processor is most concerned with, these being preferential and orientation selectivity. Preferential selectivity refers to the double-bond position the hydrogen atom attaches itself to during the saturation process. The study of orientation selectivity is centered on the fact that during contact with the catalyst, some of the double bonds may be twisted... 

The brain of any computer is the Central Processing Unit (CPU). This component does all of the calculations and performs 90 percent of all the functions of a computer. There are many different types of processors for computers. So many, in fact, that you will learn about them later in this chapter in The CPU section. Typically, in today s computers, the processor is the easiest component to identify on the motherboard. It is usually the component that has either a fan or a heat sink (or sometimes both) attached to it (as shown in Figure 2.7). These devices are used to draw away the heat a processor generates. This is done because heat is the enemy of microelectronics. Theoretically, a Pentium (or higher) processor generates enough heat that, without the heat sink, it would self-destruct in a matter of hours. 

The most unique thing about the Pentium II compared to earlier Intel processors is that it uses a Single Edge Connector (SEC) to attach to the motherboard instead of the standard PGA package that was used with the earlier processor types. The processor is on a card that can be easily replaced. Simply shut off the computer, pull out the old processor card and insert a new one. 

The most important device of any computer system is the keyboard. In fact, on Macintosh systems, if a keyboard is not hooked up the computer will not start. Actually, on any computer if a keyboard is not attached, there isn t a whole lot one can do with the computer. (It can be used as a good doorstop.) On computers that do run without a keyboard (i.e., most PCs), if the keyboard is missing an error message will occur at startup (usually a 301—Keyboard Missing error). It is the basic component used to enter information or data to the processor and storage device, so it s very important to have it connected. A standard 101-key keyboard has four separate areas ... 

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