Interconnects in computers

Another possible application for high temperature superconductors is as interconnects in computer systems with semiconducting devices (31). These could be called hybrid systems, since they involve both superconductors and semiconductors. In particular CMOS devices are well-known to have enhanced performance at 77 K and are thus potentially compatible with YBaCuO. 

At every clock tick, the developmental program of each cell (in the graph of interconnected cells) computes its next state and whether it will produce a new cell or not. Division produces a new cell with exactly the same (unchangeable) developmental program as the mother cell, but with a new location = location of the mother cell + 1. Because CGP and by extension DCGP only allow feed-forward graphs, the inputs of all cells will come from external inputs and/or the outputs of other cells, which are directly/indi-rectly connected to the external inputs. Hence, if the external inputs stay stable, then so will the outputs of all the cells in the graph. 

A business can be considered to comprise several large-scale use cases, each of which can be supported or ran by a computer system. Frequently, the importance of the major use cases has already been identified, and they have been reified as business departments. Usually, these functions operate continuously and are interconnected in some way (see Figure 16.1). 

The modern electronics era began at Bell Telephone Laboratories in 1948 with the invention of the solid-state transistor, which replaced the large thermionic vacuum tube, the mainstay of the electronics industry for the previous 40 years. Transistors were smaller and much more robust than their vacuum tube counterparts and required much less power to operate. Electronic circuits of the 1950s and early 1960s were assembled from discrete transistors, diodes, and resistors, for example, but rapid advances in circuit complexity and density, driven by developments in computer technology, soon led to an impasse, namely, how to approach the problem of interconnecting hundreds, perhaps thousands, (some visionaries would have said millions) of discrete devices into a complex circuit. 

The past decade has seen an extraordinary growth in novel new electronic structure methods and creative implementations of these methods. Concurrently, there have been important advances in middleware , software that enables the implementation of efficient electronic structure algorithms. Combined with continuing improvements in computer and interconnect hardware, these advances have extended both the accuracy of computations and the sizes of molecular systems to which such methods may be applied. 

In 1965, Gordon Moore postulated that the exponential growth in the number of transistors in an IC led to certain technical and economic advantages. Smaller transistors switch faster, allowing more operations per second. And more transistors with more interconnections enable computations of much greater complexity to be achieved. This postulate has since been codified as Moore s law, which states that the complexity of ICs as measured by the number of transistors approximately doubles every two years (see Fig. 1.1). This law has led to unprecedented growth in the computer industry. Technologies that were once available only in supercomputers are now commonly available in children s toys. Satellite communications networks that were once the domain of the mihtary now help drivers find their way to their locations. 

The essence of the material that follows is the use of a multitude of elemental nonlinear computing elements (called neurons) organized as networks reminiscent of the way in which neurons are believed to be interconnected in the brain. 

Alpert CJ, Devgan A, Quay ST (1999) Buffer insertion with accurate gate and interconnect delay computation. In DAC, pp 479 84... 

Grote, J. G., Optical interconnects for computer applications, in Tri-Service Photonics Coordinating Committee Proceedings from the DoD Photonics Conference, 1996, p. 253. 

The interconnection of computer components is critical to computer performance. The interconnection of components within a computer has been discussed, and is a key concern in the implementation of an architecture. The interconnection between computers is covered under the data and computer communications category in books and articles dealing with that topic. 

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