Fast computing ability
The work of electronic computer is based on the principle of electronic pulse circuit, and its functional components are composed of electronic circuits, in which the propagation of electric field plays a major role. We know that the electromagnetic field travels very fast, and today's high-performance computers can perform tens of billions of addition operations per second. If a person can complete an operation in one second, it will take more than 100 years for a person to work on an ordinary electronic computer for one hour. In many cases, the speed of operation plays a decisive role. For example, computer-controlled navigation requires "faster computing speed than aircraft"; Meteorological forecast needs to analyze a lot of data, such as manual calculation takes ten days and a half months, which loses the significance of forecast. With the computer, the weather forecast of an area in a few days can be worked out in a few minutes.
High enough calculation accuracy
The calculation accuracy of electronic computer is not limited in theory. Ordinary computers can reach 15 significant digits, and any accuracy requirements can be achieved by certain technical means. A famous mathematician in history, Jackson Yee, once spent 15 years to calculate pi, and only ranked 707th. Give it to the computer now, and it will be 65438+ million digits in a few hours.
Super memory ability
There are many storage units in the computer for memorizing information. Internal memory ability is an important difference between electronic computers and other computing tools. Because it has the ability of memory information, it doesn't need to fetch data from the outside every time in the operation process. It only needs to input the data into the memory unit in advance, and it can directly fetch data from the storage unit in the operation process, which greatly improves the operation speed. The capacity of computer memory can be made very large, and its memory is particularly strong.
Complex logic judgment ability
People are capable of thinking. Thinking ability is essentially a kind of logical judgment ability, which can also be said to be causal analysis ability. With the help of logical operation, the computer can make logical judgments, analyze whether the proposition is established, and make corresponding countermeasures according to whether the proposition is established. For example, there is a "four-color problem" in mathematics, which says that no matter how complicated a map is, only four colors are needed at most, so that adjacent areas can have different colors. 100 For many years, many mathematicians have been trying to prove it or overthrow it, but there has been no result, which has become a famous problem in mathematics. 1976, two American mathematicians used computers for very complicated logical reasoning, and finally verified this famous conjecture.
Ability to work automatically according to the program
Ordinary machines are controlled by people. When a person gives a command to a machine, the machine is completed and becomes an operation. The operation of the computer is also controlled by people, but because the computer has internal storage capacity, instructions can be input into the computer in advance and stored. After the computer starts to work, the instructions can be taken out from the storage unit in turn to control the operation of the computer, so that people can realize the automation of operation without interfering with the work of the computer. This working mode is called program control mode.
Electronic computers are generally divided into two categories: analog computers that process analog signals and digital computers that process digital signals. Most of them are digital computers at present. The electrical signals used by analog electronic computers to represent and process data are actual signals that simulate nature. For example, electrical signals can be used to simulate the temperature, humidity and so on that change continuously with time. This kind of electrical signal that simulates the actual signal in nature is called "analog electrical signal", and its main feature is "continuous change with time". Digital electronic computers internally process electrical signals called symbol signals or digital signals. The main feature of this signal is "discreteness", that is, there can be no third symbol between two adjacent symbols. What we usually call a computer refers to a digital electronic computer.
The application field of computer has penetrated into all walks of life, changed the traditional way of working, studying and living, and promoted the development of society. The main application fields of computers are as follows:
1. Scientific calculation (or numerical calculation)
Scientific calculation refers to the use of computers to calculate mathematical problems raised in scientific research and engineering technology. In the work of modern science and technology, the problems of scientific calculation are complicated. Using the computer's high-speed calculation, large storage capacity and continuous operation ability, various scientific calculation problems that can't be solved manually can be realized.
For example, in order to determine the size of components in architectural design, a series of complex equations are derived through elasticity, which can not be solved for a long time because the calculation method can not keep up. Computer can not only solve this kind of equation, but also cause a breakthrough in elasticity theory, and the finite element method appears.
2. Data processing (or information processing)
Data processing refers to a series of activities such as collection, storage, sorting, classification, statistics, processing, utilization and dissemination of various data. According to statistics, more than 80% of computers are mainly used for data processing, and this kind of workload is extensive, which determines the dominant direction of computer application.
Data processing has gone through three stages from simple to complex, namely:
① Electronic Data Processing (EDP), which realizes the single item management of a department based on the file system.
(2) Management Information System (MIS), which uses database technology as a tool to realize the overall management of a department and improve work efficiency.
(3) Decision Support System (DSS), based on database, model base and method base, helps management decision makers to improve their decision-making level and improve the correctness and effectiveness of business strategies.
At present, data processing has been widely used in office automation, enterprise computer-aided management and decision-making, information retrieval, book management, film and television animation design, accounting computerization and other fields. Information is forming an independent industry, and multimedia technology makes information not only appear as numbers and words, but also as sound and image information.
3. Assistive technology (or computer-aided design and manufacturing)
Computer-aided technology includes CAD, CAM and CAI.
(1) computer-aided design.
Computer-aided design is a technology that uses computer system to assist designers in engineering or product design, so as to achieve the best design effect. It has been widely used in airplanes, automobiles, machinery, electronics, architecture and light industry. For example, in the design process of electronic computer, CAD technology is used to simulate architecture, logic, plug-in division, automatic wiring and so on. , thus greatly improving the degree of automation of design work. For another example, in the process of architectural design, CAD technology can be used for mechanical calculation, structural calculation and drawing architectural drawings, which not only improves the design speed, but also greatly improves the design quality.
⑵ Computer Aided Manufacturing (CAM).
Computer-aided manufacturing is a process of managing, controlling and operating production equipment by computer system. For example, in the manufacturing process of products, computers are used to control the operation of machines, process the data needed in the production process, control and process the flow of materials, and detect products. Using CAM technology can improve product quality, reduce cost, shorten production cycle, improve productivity and improve working conditions.
Integrating CAD and CAM technology to realize design and production automation is called computer integrated manufacturing system (CIMS). Its realization will truly realize the unmanned chemical plant (or workshop).
⑶ Computer-aided teaching.
Computer-aided teaching is the use of computer systems to use courseware for teaching. Courseware can be developed and produced with writing tools or advanced languages, which can guide students to learn step by step and circularly, so that students can easily learn what they need from courseware. The main characteristics of CAI are interactive education, individual guidance and personalized teaching.
4. Process control (or real-time control)
Process control is to use computer to collect test data in time and quickly adjust or control the controlled object according to the optimal value. Using computer for process control can not only greatly improve the automation level of control, but also improve the timeliness and accuracy of control, thus improving working conditions and improving product quality and qualified rate. Therefore, computer process control has been widely used in machinery, metallurgy, petroleum, chemical industry, textile, hydropower, aerospace and other departments.
For example, in the automobile industry, using computers to control machine tools and control the whole assembly line can not only realize the automation of parts with high precision and complex shapes, but also make the whole workshop or factory realize automation.
5. Artificial intelligence (or intelligent simulation)
Artificial intelligence is a computer simulation of human intelligence activities, such as perception, judgment, understanding, learning, problem solving and image recognition. At present, the research of artificial intelligence has made many achievements, and some of them have begun to move towards the practical stage. For example, expert systems that can simulate senior medical experts for disease diagnosis and treatment, intelligent robots with certain thinking ability, and so on.
6. Network application
The combination of computer technology and modern communication technology constitutes a computer network. The establishment of computer network not only solves the communication between computers in a unit, a region and a country, but also greatly promotes the international transmission and processing of various data such as words, images, videos and sounds.
What are the characteristics of embedded computer system compared with general computer system? Provides you with a new embedded training.
1. Embedded system is usually an application-oriented embedded CPU. The biggest difference between embedded CPU and general CPU is that most of them work in systems designed for specific user groups. They usually have the characteristics of low power consumption, small size and high integration, and can integrate many tasks completed by the board card in the general CPU into the chip, which is beneficial to the miniaturization of embedded system design, greatly enhances mobility and is more closely coupled with the network.
2. Embedded system is the product of advanced computer technology, semiconductor technology and electronic technology combined with specific applications in various industries. This determines that it must be a technology-intensive, capital-intensive and highly decentralized innovative knowledge integration system.
3. The hardware and software of embedded system must be designed with high efficiency, customization and redundancy, and strive to achieve higher performance on the same silicon chip area, so as to be more competitive in the selection of processors in specific applications. 4. Embedded system is organically combined with specific applications, and its upgrade is also synchronized with specific products, so once embedded system products enter the market, their life cycle is very long.
5. In order to improve the execution speed and system reliability, the software in the embedded system is generally solidified in the memory chip or microcontroller itself, rather than stored in the disk and other carriers.
6. The embedded system itself does not have bootstrap development capability. Even after the design is completed, users usually cannot modify the program functions. Only one set of development tools and environment can be developed.
What are the aspects of computer system software? What are the computer system software? Computer software consists of system software, supporting software and application software. System software is the software closest to the hardware layer in a computer system, and other software generally plays a role through system software. It has nothing to do with specific application fields, such as compilers and operating systems. Compiler. Compilers translate programs written in high-level languages into equivalent executable programs written in low-level languages. The operating system is responsible for managing various resources of the system and controlling the execution of programs. In the design of any computer system, system software should be given priority. (The system software consists of compiler, operating system and system tool software. )
What is the main information security goal of financial computer system? 1. Ensure the integrity and confidentiality of information. The information transmission of online banking system is completely open on the Internet, and any legal user can exchange and obtain information here. In order to ensure the integrity and confidentiality of information, dynamic information can be signed to ensure the integrity of information, and key encryption can be used to ensure the confidentiality of information; Static information can be specially saved, and files can be locked by passwords to ensure the integrity and confidentiality of information.
2. Strictly authenticate the identity of network access users. Public key mechanism (PKI) can be used to authenticate access users.
3. Establish a network anti-virus mechanism. Establish a strict anti-virus system to monitor all servers, and at the same time establish a virus monitoring system to give early warning to mobile information infected with viruses, and have corresponding compulsory means.
4, illegal invasion of security audit and tracking. An important content of online banking is to prevent illegal intrusion. Although the firewall can play a certain role, it is impossible to stop all intrusions. Therefore, we should strengthen security audit and follow-up afterwards to stop and track intruders.
5. Information system security. It mainly solves the security problems of information system security design, production, testing, operation and maintenance, and its objects include integrated circuits, smart cards, computer equipment, communication equipment, video equipment, control equipment, control systems, network equipment, terminal equipment, operating systems, database systems and application systems.
What versions of the computer system are there? At present, the commonly used computer system is called Windows operating system. Windows operating system is divided into the following versions from old to new:
Windows 1.0: Based on the MS-DOS operating system, it is actually not an operating system itself, but only an application software based on DOS at most. After that, Windows 2.x and 3.x are still DOS-based operating systems. Windows 1.0 operating system is Microsoft's first attempt at user graphical interface of personal computer operating platform, which is based on MS-DOS operating system. Windows 1.0 essentially declared the end of the DOS operating system.
Windows 2.0:1987 65438+released on February 9, with an initial price of 100 USD. This is an operating system based on MS-DOS. Windows version of Microsoft Windows graphical user interface that looks like Mac OS. But this version is still not recognized by users. Later, Windows 386 and Windows 286 were introduced and some improvements were made, which laid a good technical foundation for the success of Windows 3.0. And it has more functions than Windows 1.0. It is a little improved because it is the more popular version 3.0.
Windows 3.x:Windows 3.x family of Windows series operating platforms is released between 1990 and 1994. Among them, version 3.0 is the first successful version in the world. Microsoft's operating system can compete with Apple's Macintosh and Commodore's Amiga in graphical interface. Windows 3.x was based on MS-DOS operating system and was later replaced by Windows 95.
Windows 95: 1995 operating system was launched on August 24th. Windows 95 is a mixed 16-bit /32-bit Windows system with version number 4.0 and development code name Chicago. Windows 95 is the first time to give up its support for the previous generation 16-bit x86, so it needs Intel's 80386 processor to run in protected mode, or a compatible faster processor. At the same time, it is also the first Windows version with a special version of DOS (Microsoft DOS 7.0). It brings a more powerful, stable and practical desktop graphical user interface, and also ends the competition among desktop operating systems. Within a year or two of its release, it became one of the most successful operating systems in history.
Windows 98: The mixed 16-bit /32-bit Windows operating system released by Microsoft Corporation on June 25th, 1998. Its version number is 4. 1, and its development code is Memphis. Windows 98 fully integrates the Inter standard, and unifies and simplifies the desktop with Inter technology, so that users can find and browse the information stored in personal computers and the Internet more quickly and simply. Second, it is faster and more stable. By providing brand-new self-maintenance and updating functions, Windows 98 can save users a lot of system management work, so that users can concentrate on their work or games.
Windows Me: Windows Me (Windows Millennium Edition) is a 16-bit /32-bit mixed Windows system, which was released on September 14, 2000. Windows Me is the last 9X series Windows based on DOS, version number: 4.9. Its name has three meanings. One is to commemorate the year 2000. Me means Millennium in English. Besides, I also mean myself. Me is the objective case of "I" in English. In addition, Me has the significance of multimedia application (English is Multimedia).
Windows 2000 is a 32-bit Windows operating system of Windows NT series. The English version of Windows NT5.0 was officially released in San Francisco on February 17, 2000, and the Chinese version was officially listed in Beijing, China on March 20th of the same year. Windows 2000 is an interruptible, business-oriented graphical operating system, which is designed for 32-bit Intel x86 computers with single processors or symmetric multiprocessors.
Windows XP: Microsoft introduced an operating system for personal computers, including commercial and home desktop computers. Its RTM version was released on August 24th, 20001year. The retail version of 20065438+010/kloc-0 was launched on October 25th. Its name "XP" means "experience" in English. It is the next generation Windows operating system after Windows 2000 and Windows ME, and it is also the first consumer-oriented operating system in Microsoft. On April 8, 20 14, 12, Windows XP was officially eliminated.
Windows Vista: Compared with the previous version of Windows Vista, Windows Vista has added hundreds of new functions, including a brand-new graphical user interface named "Aero", enhanced search function (Windows indexing service), new media creation tools (such as Windows DVD Maker) and redesigned network, audio, output (printing) and display subsystems. Vista also uses peer-to-peer technology to improve the display and communication capabilities of computer systems in home networks, which will make it easier for different computers or devices to share files and multimedia content. For developers, Vista uses. NET Framework makes it easier for developers to write high-quality programs than traditional Windows API. Microsoft has also improved the security of Vista. Compared with Windows XP, Vista adds user management mechanism (UAC) and built-in malware detection tool (Windows Defender).
Windows 7:Windows 7 continues the Aero style of Windows Vista, even better (version upgraded to 1. 1). It is divided into family basic edition, family advanced edition, professional edition, enterprise edition and flagship edition.
Windows 8: Developed by Microsoft, it was officially listed on 20 12, 10126, with revolutionary changes. The system's unique metro start screen interface and touch interactive system are designed to make people's daily computer operations simpler and faster, and provide people with an efficient and relaxed working environment. Windows 8 supports the chip architecture of Intel and AMD, and is applied to desktops, notebooks and tablets.
Windows 10: Microsoft is developing a new generation of cross-platform and cross-device application operating system. At present, the beta version of this operating system has been released, and public beta has begun. The official version was released on July 29th, 20 15.
What accessories does the computer system have? This system is actually a software.
If a computer has any accessories, it can be roughly said to be a central processing unit, a graphics card, a motherboard, a hard disk, and a memory handle.
Main technical indicators of computer system What are the main technical indicators and system configuration of computer system?
First, the main performance indicators of the computer
1) word length: word length is the number of binary data bits that CPU can directly process, which is directly related to the calculation accuracy, function and speed of computer. The longer the word length, the stronger the processing power. Common microcomputer word lengths are 8 bits, 16 bits and 32 bits.
2) Operation speed: Operation speed refers to the number of instructions that the computer can execute per second, generally in MIPS.
3) Main frequency: Main frequency refers to the clock frequency of the computer, expressed in MHz.
4) Memory capacity: Memory capacity refers to the total number of bytes that can store information in memory, generally in KB and MB.
5) Peripheral configuration: Peripheral refers to the input/output equipment of the computer.
6) Software configuration: including operating system, computer language, database language, database management system, network communication software, Chinese character support software and other various application software.
2. The main configuration of microcomputer system
The basic configuration of microcomputer mainly includes host, keyboard, disk drive, hard disk, display and so on.
What are the main technical measures to ensure the security of computer systems? Measure 1: Encrypt the whole hard disk.
Measure 2: Install anti-virus and anti-spyware software.
Step 3: Lock your computer (with hardware or software).
Measure 4: Install tracking software.
Measure 5: Install a software firewall.
Measure 6: Keep it updated.
Measure 7: Use a strong password.
Measure 8: Use the wireless network carefully.
Measure 9: Disable Windows services that users don't need.
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What are the common computer systems? disc operating system (DOS)
windows 95
windows98
Millennium operating system
windows 2000
windows 2003
Windows XP
Vesto Knicks
Linux operating system