|
Digital Electronic Computer
In computer science, a digital electronic computer is a computer machine which is both an electronic computer and a digital computer. Examples of digital electronic computers include the IBM PC, the Apple Macintosh, and modern smartphones. When computers that were both digital and electronic appeared, they displaced almost all other kinds of computers, but computation has historically been performed in various non-digital and non-electronic ways: the Lehmer sieve is an example of a digital non-electronic computer, while analog computers are examples of non-digital computers which can be electronic (with analog electronics), and mechanical computers are examples of non-electronic computers (which may be digital or not). An example of a computer which is both non-digital and non-electronic is the ancient Antikythera mechanism found in Greece. All kinds of computers, whether they are digital or analog, and electronic or non-electronic, can be Turing complete if they have sufficient ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lehmer Sieve
Lehmer sieves are mechanical devices that implement sieves in number theory. Lehmer sieves are named for Derrick Norman Lehmer and his son Derrick Henry Lehmer. The father was a professor of mathematics at the University of California, Berkeley at the time, and his son followed in his footsteps as a number theorist and professor at Berkeley. A sieve in general is intended to find the numbers which are remainders when a set of numbers are divided by a second set. Generally, they are used in finding solutions of Diophantine equations or to factor numbers. A Lehmer sieve will signal that such solutions are found in a variety of ways depending on the particular construction. Construction The first Lehmer sieve in 1926 was made using bicycle chains of varying length, with rods at appropriate points in the chains. As the chains turned, the rods would close electrical switches, and when all the switches were closed simultaneously, creating a complete electrical circuit, a solution had ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Stored Program Computer
A stored-program computer is a computer that stores program instructions in electronically or optically accessible memory. This contrasts with systems that stored the program instructions with plugboards or similar mechanisms. The definition is often extended with the requirement that the treatment of programs and data in memory be interchangeable or uniform. Description In principle, stored-program computers have been designed with various architectural characteristics. A computer with a von Neumann architecture stores program data and instruction data in the same memory, while a computer with a Harvard architecture has separate memories for storing program and data. However, the term ''stored-program computer'' is sometimes used as a synonym for the von Neumann architecture. Jack Copeland considers that it is "historically inappropriate, to refer to electronic stored-program digital computers as 'von Neumann machines'". Hennessy and Patterson wrote that the early Harvard m ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Abacus
The abacus (''plural'' abaci or abacuses), also called a counting frame, is a calculating tool which has been used since ancient times. It was used in the ancient Near East, Europe, China, and Russia, centuries before the adoption of the Hindu-Arabic numeral system. The exact origin of the abacus has not yet emerged. It consists of rows of movable beads, or similar objects, strung on a wire. They represent digits. One of the two numbers is set up, and the beads are manipulated to perform an operation such as addition, or even a square or cubic root. In their earliest designs, the rows of beads could be loose on a flat surface or sliding in grooves. Later the beads were made to slide on rods and built into a frame, allowing faster manipulation. Abacuses are still made, often as a bamboo frame with beads sliding on wires. In the ancient world, particularly before the introduction of positional notation, abacuses were a practical calculating tool. The abacus is still used to te ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Beowulf Cluster
A Beowulf cluster is a computer cluster of what are normally identical, commodity-grade computers networked into a small local area network with libraries and programs installed which allow processing to be shared among them. The result is a high-performance parallel computing cluster from inexpensive personal computer hardware. The name ''Beowulf'' originally referred to a specific computer built in 1994 by Thomas Sterling and Donald Becker at NASA. The name "Beowulf" comes from the Old English epic poem of the same name. No particular piece of software defines a cluster as a Beowulf. Typically only free and open source software is used, both to save cost and to allow customisation. Most Beowulf clusters run a Unix-like operating system, such as BSD, Linux, or Solaris. Commonly used parallel processing libraries include Message Passing Interface (MPI) and Parallel Virtual Machine (PVM). Both of these permit the programmer to divide a task among a group of networked computers, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cluster Computer
A computer cluster is a set of computers that work together so that they can be viewed as a single system. Unlike grid computers, computer clusters have each node set to perform the same task, controlled and scheduled by software. The components of a cluster are usually connected to each other through fast local area networks, with each node (computer used as a server) running its own instance of an operating system. In most circumstances, all of the nodes use the same hardware and the same operating system, although in some setups (e.g. using Open Source Cluster Application Resources (OSCAR)), different operating systems can be used on each computer, or different hardware. Clusters are usually deployed to improve performance and availability over that of a single computer, while typically being much more cost-effective than single computers of comparable speed or availability. Computer clusters emerged as a result of convergence of a number of computing trends including t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Supercomputer
A supercomputer is a computer with a high level of performance as compared to a general-purpose computer. The performance of a supercomputer is commonly measured in floating-point operations per second ( FLOPS) instead of million instructions per second (MIPS). Since 2017, there have existed supercomputers which can perform over 1017 FLOPS (a hundred quadrillion FLOPS, 100 petaFLOPS or 100 PFLOPS). For comparison, a desktop computer has performance in the range of hundreds of gigaFLOPS (1011) to tens of teraFLOPS (1013). Since November 2017, all of the world's fastest 500 supercomputers run on Linux-based operating systems. Additional research is being conducted in the United States, the European Union, Taiwan, Japan, and China to build faster, more powerful and technologically superior exascale supercomputers. Supercomputers play an important role in the field of computational science, and are used for a wide range of computationally intensive tasks in var ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Multiple Instruction, Multiple Data
In computing, multiple instruction, multiple data (MIMD) is a technique employed to achieve parallelism. Machines using MIMD have a number of processors that function asynchronously and independently. At any time, different processors may be executing different instructions on different pieces of data. MIMD architectures may be used in a number of application areas such as computer-aided design/computer-aided manufacturing, simulation, modeling, and as communication switches. MIMD machines can be of either shared memory or distributed memory categories. These classifications are based on how MIMD processors access memory. Shared memory machines may be of the bus-based, extended, or hierarchical type. Distributed memory machines may have hypercube or mesh interconnection schemes. Examples An example of MIMD system is Intel Xeon Phi, descended from Larrabee microarchitecture. These processors have multiple processing cores (up to 61 as of 2015) that can execute different instr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Parallel Computer
Parallel computing is a type of computation in which many calculations or processes are carried out simultaneously. Large problems can often be divided into smaller ones, which can then be solved at the same time. There are several different forms of parallel computing: bit-level, instruction-level, data, and task parallelism. Parallelism has long been employed in high-performance computing, but has gained broader interest due to the physical constraints preventing frequency scaling.S.V. Adve ''et al.'' (November 2008)"Parallel Computing Research at Illinois: The UPCRC Agenda" (PDF). Parallel@Illinois, University of Illinois at Urbana-Champaign. "The main techniques for these performance benefits—increased clock frequency and smarter but increasingly complex architectures—are now hitting the so-called power wall. The computer industry has accepted that future performance increases must largely come from increasing the number of processors (or cores) on a die, rather than ma ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
ARM Architecture
ARM (stylised in lowercase as arm, formerly an acronym for Advanced RISC Machines and originally Acorn RISC Machine) is a family of reduced instruction set computer (RISC) instruction set architectures for computer processors, configured for various environments. Arm Ltd. develops the architectures and licenses them to other companies, who design their own products that implement one or more of those architectures, including system on a chip (SoC) and system on module (SOM) designs, that incorporate different components such as memory, interfaces, and radios. It also designs cores that implement these instruction set architectures and licenses these designs to many companies that incorporate those core designs into their own products. There have been several generations of the ARM design. The original ARM1 used a 32-bit internal structure but had a 26-bit address space that limited it to 64 MB of main memory. This limitation was removed in the ARMv3 series, which ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Intel Core I7
The following is a list of Intel Core i7 brand microprocessors. Introduced in 2008, the Core i7 line of microprocessors are intended to be used by high-end users. Desktop processors Nehalem microarchitecture (1st generation) "Bloomfield" (45 nm) * All models support: MMX, SSE, SSE2, SSE3, SSSE3, SSE4.1, SSE4.2, Enhanced Intel SpeedStep Technology (EIST), Intel 64, XD bit (an NX bit implementation), Intel VT-x, Hyper-threading, Turbo Boost, Smart Cache. * FSB has been replaced with QPI. * Transistors: 731 million * Die size: 263 mm * Steppings: C0, D0 "Lynnfield" (45 nm) * All models support: MMX, SSE, SSE2, SSE3, SSSE3, SSE4.1, SSE4.2, Enhanced Intel SpeedStep Technology (EIST), Intel 64, XD bit (an NX bit implementation), TXT, Intel VT-x, Intel VT-d, Hyper-threading, Turbo Boost, Smart Cache. * Core i7-875K features an unlocked multiplier and does not support Intel TXT and Intel VT-d. * FSB has been replaced with DMI. *Moves the QPI link and ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
AMD FX
AMD FX was a series of high-end AMD microprocessors for personal computers which debuted in 2011, claimed as AMD's first native 8-core desktop processor. The line was introduced with the Bulldozer microarchitecture at launch (codename Zambezi), and was then succeeded by its derivative Piledriver in 2012 (codename Vishera). The line aimed at competing with the Intel Core line of desktop processors, and in particular the Sandy Bridge and Ivy Bridge architectures. AMD's successor architecture, Zen, was released in 2017 under the Ryzen brand, replacing the FX series and competing with Intel's Skylake architecture. History Prior to FX Launch In the years prior to the AMD FX range of processors, the AMD Phenom II and Athlon II lineup of processors, while not beating Intel's Core lineup in raw performance, were generally competitive when their price was taken into account. By the end of Phenom's lifespan, however, Intel's Sandy Bridge architecture could provide performance th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Central Processing Unit
A central processing unit (CPU), also called a central processor, main processor or just processor, is the electronic circuitry that executes instructions comprising a computer program. The CPU performs basic arithmetic, logic, controlling, and input/output (I/O) operations specified by the instructions in the program. This contrasts with external components such as main memory and I/O circuitry, and specialized processors such as graphics processing units (GPUs). The form, design, and implementation of CPUs have changed over time, but their fundamental operation remains almost unchanged. Principal components of a CPU include the arithmetic–logic unit (ALU) that performs arithmetic and logic operations, processor registers that supply operands to the ALU and store the results of ALU operations, and a control unit that orchestrates the fetching (from memory), decoding and execution (of instructions) by directing the coordinated operations of the ALU, registers and other co ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
.svg "Click for more on -> Intel Core I7")
