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以下就是翻译,希望可以帮助到你History of computer development, and future development areas I. Introduction to Computer History Computational tools used by human beings, with the development of production and social progress, from simple to complex, from lower to higher development, computational tools have emerged, such as abacus, slide rule, hand mechanical computers, electrical machinery and computer . In 1946, the world's first electronic digital computer (ENIAC) was born in the United States. This computer has more than 18,000 shared power in the tubes, an area of 170m2, the total weight of 30t, power 140kw, computing speed of the 5000 additions per second, 300 times multiplication. Computer in just 50 years after the tubes, transistors, integrated circuits (IC) and ultra large scale integration (VLSI) four stages of development, so that the computer smaller and smaller, more powerful, the price getting lower and lower, more and more widely, currently moving intelligence (fifth generation) computer direction. 1. The first generation of computer The first generation of electricity in the computer is from 1946 to 1958. They are larger, lower operation speed, storage capacity is small and expensive. Not easy to use, in order to solve a problem, the complexity of programmed elusive. This generation is mainly used for scientific computing, scientific research only in the key sectors or departments. 2. Second-generation computer Second-generation computer is from 1958 to 1965, they all use the transistor as an electronic device, the operation speed than the first generation of faster computers in recent times, the volume of several one-tenth of the original. In terms of software to start using computer algorithms language. This generation not only for scientific computing, but also for data processing and transaction processing and industrial control. 3. Third-generation computer The third generation of computer is from 1965 to 1970. The main characteristics of this period is, the small-scale integrated circuits for electronic devices, and operating system appears to make more powerful computers, applications and more wide. They not only used for scientific computing, but also for word processing, business management, automatic control and other fields, there has been computer technology and communication technology combines information management system for production management, traffic management, information retrieval and other fields.
jessicabeck
艾默生过程管理旗下的高准(Micro Motion)公司新近推出MVD多参数数字变送器,它以DSP数字信号处理技术的使用为特点,显示了高准公司在科里奥利质量流量测量技术上的雄厚实力。 高准 MVD多参数数字技术提供了一个模式化的结构来重新定义传感器和变送器,并使流量计工作得更灵巧。DSP数字信号处理器的核心处理器与传感器安装在一起,把来自科里奥利传感器中的模拟信号转换为数字信号,并产生一个正比于质量流量的电子信号。 1000系列和2000系列两种变送器可与核心处理器之间通过普通的4线电缆相连接,它们将输出最终测量信号、提供显示和一些其他的功能。变送器也可以一体地与核心处理器安装在一起。 一 什么是DSP数字信号处理器 DSP数字信号处理器是一个实时处理信号的微处理器。家用电脑的微处理器根据储存在存储器里的数据进行工作,这对于结算支票或玩电子游戏是合适的,但它不能处理某些现实世界里的东西,如音频信号、视频信号、医疗传感器的信号或来自于科里奥利传感器的信号。这里我们需要一个非常快的微处理器对这些信号做各种我们想要做的分析。 家用电脑需要显示器、磁盘驱动器、打印机、软件和一些连接电缆,像家用电脑里的微处理器一样,DSP数字信号处理器也需要支持的软件和硬件。在DSP的世界里,我们需要做的第一件事就是要把现实世界里的信号转换成为DSP世界里的信号,所用的装置被称为“模拟 —数字转换器”。 字串3 我们也需要一些软件去操作“数字化”信号,让我们举一个例子来看看我们用软件可做些什么。在远距离通话中,我们有时会听到自己声音的回声,这令人气恼。人的耳朵习惯于过滤掉短回声,但是长回声使通信非常困难。电话公司复制了你的声音然后在合适的时间加到它的反向以消除回声,不是回声没有发生,它只是被非常复杂的DSP数字信号处理软件过滤掉了。在科里奥利流量计里,我们使测量管在一个已知的频率下振动,因此任何在此振动频率范围之外的频率都是“噪声”,需要除掉它们以准确地确定质量流量。例如,一个50Hz或60Hz的信号很可能来源于与附近动力线的耦合。如何在实际上“过滤”这些多余的信号则需要一些更多的在那时刻所得到的背景信息,图1表明了噪声如何出现在原转换器信号上,以及被过滤后的最终信号。 既然我们已经处理了信号,就需要把它从数字世界再转换回到现实世界,完成这项任务的装置是“数字—模拟转换器”。 我们需要一些存储器来储存DSP数字信号处理程序,也需要一些控制装置去实现DSP数字信号处理器。字串1 二 DSP数字信号处理技术为科里奥利质量流量计带来的好处 和家用电脑处理数据带来的好处一样,DSP数字信号处理技术也给处理现实世界的信号带来了同样的好处:DSP数字信号处理器比传统的模拟处理器要小得多,这正是我们如何能把所有技术都封装到核心处理器中并使传感器智能化的原因;比起传统的模拟处理器,DSP数字信号处理器使用了更小的能量和更少的元件,并提高了可靠性;DSP数字信号处理器的精确度至少比类似的模拟处理器高一个数量级,这意味着即使较差的传感器信号也能得出较好的最终测量值;通过软件更新,核心处理器可适用于其他的传感器类型。对于高准产品来说,这意味着市场开拓更快;对于用户来说,这意味着更少的备用部件。 三 和DSP数字信号处理器有关的一些数学知识 自然界存在的信号一般是连续的,并可被连续变化的电压信号所表示。科里奥利流量计的信号也是连续信号,当我们通过一个模拟—数字转换器来发送信号时,事实上我们已把信号量化为离散的或数字化的样本。例如,假设我们通过一个12位的ADC以每秒1000个样本的采样率来传送转换器的电压,每毫秒我们将信号量化为212=4096个可能的级别之一。图2显示了一个已被量化后的信号。字串4 ADC运行一秒我们可采集1000个转换器电压的样本,我们称样本的数目为N。如果需要,我们可把所有的采样值加在一起,然后除以N来计算转换器电压的平均值。以一个类似的形式我们可计算信号的标准偏差,平均值代表我们想测量的实际信号,而标准偏差代表噪声信号。平均值的平方除以标准偏差的平方被称作信噪比或SNR。信噪比越高,被分析的数据的质量就越高。这些计算可用于计算被测变量的值。过滤和减小带宽(技术上叫作十倍程下降率)可用于提高信噪比和质量流量的精确度。 四 傅立叶分析 傅立叶分析是以法国数学家和物理学家 Jean Baptiste Loseph Fourier的名字命名的分析方法。 傅立叶认为任何连续的周期信号可被适当选择的正弦信号波的总和所描述。取一个连续的周期信号并把它转换为一族正弦波被定义为进行一个傅立叶变换。傅立叶变换在数学上很复杂,但我们只需大致了解即可。核心处理器取已量化的转换器信号并进行了信号的傅立叶变换,如图3所示。字串4 五 数字滤波 图3中信号的频谱,只有一个信号数据,其余的都是噪声,100Hz的信号代表了测量管的振动频率。我们也看到了在200Hz、300Hz、400Hz等频率处的信号,这些被称为二次、三次和四次谐波。我们还看到了一个来源于动力线耦合的60Hz的小信号。 这些数据在DSP的存储器里只是一个表格,我们想做的是抛弃任何实际测量中所不需要的信息,也就是要忽略掉100Hz测量管频率之外的信息,这被称为数字滤波。 注意到在图3中只有一个信号在100Hz测量管频率附近,在较老的传感器中,通常确定信号附近什么是数据和什么是噪声都是非常困难的。高准传感器在测量管工作频率附近有一个格外高的信号纯度,这就是高准质量流量计具有高精确度的一个重要原因。 六 DSP数字信号处理技术对高准质量流量计的实际意义 与使用时间常量去阻抑和稳定信号相比,使用DSP数字信号处理技术的主要好处之一是能够以一个被提高了的采样率去过滤实时信号,这使得流量计对流量的阶跃变化的响应时间快多了。使用MVD多参数数字变送器的响应时间比使用模拟信号处理的传统变送器快2~4倍,更快的响应时间会提高短批量控制的效率和精确度。在发动机测试装置里,我们能更好地测量发动机对燃料喷射的阶跃变化的响应。用一个紧凑的校验装置还能提高现场校验高准流量计的能力。图4是MVD多参数数字科里奥利变送器、压力变送器和普通科里奥利变送器对流量的阶跃变化的响应。字串8 DSP数字信号处理技术另一个颇有价值的实例是气体测量。气体测量是一个更富有挑战性的应用,因为高速气体通过流量计会引起相对较严重的噪声。通过高准Elite系列传感器,与流量信号混杂的噪声已被减至最小。现在DSP数字信号处理技术能更好地滤波,并进一步减小了质量流量计对噪声的敏感度。采用MVD多参数数字变送器测量气体的结果在重复性和精确度上都有了显著提高,效果如图5、图6所示。 七 未来 DSP数字信号处理技术提供了一个“通往处理的窗户”,今天,当浏览这个窗户时,首先集中在测量管振动频率附近的信号上。实际上,有意地抛弃了其余的信息,很可能正是隐藏在这些“无用的”数据里的信息会铺平通往新的诊断技术的道路。例如,频谱分析可能会引导我们取得在夹杂空气或团状流动流体测量上的进展,流体在测量管内壁的附着也是另一个有希望被DSP数字信号处理技术检测到的故障,频谱的变化也很可能被用于预测传感器的故障。 字串5 八 总结 今天,DSP数字信号处理技术通过给予质量流量计一个更快、更可靠、更高效、更稳定、更灵活的的解决办法,体现了它的价值。这也使得我们的传感器更灵巧。对于未来,高准公司充满了信心,DSP数字信号处理技术将在推动流量测量上显示出巨大的潜力。
晴猫猫天
来自百度:DESIGN AND IMPLEMENTATION OF PRODUCTION PLANNING MANAGEMENT SYSTEM OF SURVEYING AND MAPPING PROJECTKEY WORDS: GIS,Design,Analysis,Application,Management,ProductionABSTRACT:With the development of photogrammetry and spatial information sciences, we have found many new methods to solve the technical problem in surveying and mapping project. But there is a little research on the project management. Traditional management method is complex and time-consuming. Now, we need use new technique to improve the management method for enhancing management level. Taking “National Western Surveying and Mapping Project on 1:50000 Topological Maps Blank Area” as an example, this paper focus on production planning management. The project is remarkable, not only the task and extent is tremendous, but also the staff and stuff are excessive. The Blank Area has atrocious weather and extreme hypsography. All of the conditions increase the project management difficulty. For reasonable planning and logical budget, we designed and realized a production planning management system to give the decision support to the managers. This paper studies the system’s requirement analysis, system structure and function in detail.1. INTRODUCTIONNowadays, Geographical Information Systems(GIS) are powerful and useful as means of information, visualization and research tools(Quan Bao,2004). Most GIS software is more suited to providing limited types of output than as a tool to support, at anything other than a superficial level, tactical or strategic decision-making processes. To improve the usefulness of GIS as a decision support tool, two needs are apparent. First, decision-makers require methods that allow them to easily select alternatives across a number of relevant criteria. Second, it is necessary to explicitly recognize that most decision-making processes involve multiple participants. Since problem solving id often characterized by multiple and conflicting objectives, methods that contribute toward more a completely aiding decision system are required.
飞扬嗒兜兜
Computer history, field and the future developmentA, computer history profileUsed by humans computational tool is with the development of production and social progress, from simple to complex, from low to high, the development process of calculating tool successively appeared like abacus, slide rule, computer, electric machinery brain-scanningexperiments mechanical computer, etc. In 1946, the world's first digital electronic computer (ENIAC) was born in the United States. This computer to share more than 18,000 composed, cover an area of electricity in tube 170m2 total weight, 30t, consumed for 140kw, speed 5000 cycles per second to add, 300 times the multiplication.Electronic computers in a short period of more than 50 years after the electron tubes, transistors, integrated circuit (IC) and large scale integration (VLSI) four stages of development, make the computer volume more and more small, function is more and more strong, the price is lower, used more widely and is currently facing intelligent (the fifth generation computer direction.1. The first generation of the electronic computerThe first generation of electricity in computer from 1946 to 1958. They have large size, low operation speed and storage capacity is not big, and expensive. Use isn't very convenient, in order to solve a problem, the program compiled by the complexity of the unspeakable. This generation of computers is mainly used in scientific computing, only the important department or scientific research departments for use.2. The second generation of the electronic computerThe second generation of computers from 1958 to 1965, they all adopt transistors as electronic components, its speed than the first generation of computers speed increased nearly 100 times, volume for a small percentage of the original. In software began using computer algorithmic language. This generation of computers is not only used in scientific calculations, also used for data processing and transaction processing and industrial control.3. The third generation electronic computerThe third generation of computers from 1965 to 1970. This period is the main feature of integrated circuits, small-scale for electronic devices, and appear operation system, the computer's function is more and more strong, application more widely. They are not only used in scientific computing, and for the word processing, enterprise management, automatic control and other fields, appeared computer technology and communication technology, combining information management system, can be used in the production management, traffic management, information retrieval, etc.4. The fourth generation electronic computerThe fourth generation of computers is to show from 1970 after using (LSI) and large scale integration (VLSI) as main electronic components made of computer. For example 80386 microprocessors microprocessors, in an area of about 10mm X l0mm single chip can be integrated about 32 million transistors.The fourth generation of computers is another important branch of large-scale, vlsi developed based microprocessor and microcomputer.5. The fifth generation computerThe fifth generation computer will put information acquisition, storage, manipulation, communication and artificial intelligence together has form reasoning, lenovo, learning and explain capabilities. Its system structure will break through the traditional von debbi according to the concept of Raman machine, realize the height of parallel processing.Second, computer development directionThe next computer will with very large scale integrated circuit as the foundation, to giant change, miniaturization, network and intelligent direction.Giant of 1.Giant change refers to computer operation speed higher, storage capacity greater, function stronger. At present are developing giant computer its speed can reach per 10 billion times.Nano-scale 2.Micro computer has entered the instrument and meter, household appliances such as small instruments, also as industrial control process of heart, make the equipment to realize "intelligent". With the further development of microelectronics technology, notebook type, such as palmtop microcomputer will end in more optimal price-performance get the welcome of people.Network 3.Along with the computer application deeply, especially the home computer is becoming more and more popular, on the one hand, hope many users can share information resources, on the other hand also hope all between computers can mutual information communication.The computer network is modern communication technology and computer techniques. Computer network yourself in the modern enterprise management plays more and more important role, such as bank system and commercial systems, transportation system, etc.Intelligent 4.Computer artificial intelligence research is based on modern scientific basis. Artificial intelligence is an important direction of computer development, the new generation computer, will can simulate the sensation of behavior and thinking process, mechanism of "see", "hear", "says", "think", "do", with logical reasoning, learning, and proof ability.选为最佳答案吧 谢谢
Information literacy Knowing how to find data from several sources, select relev
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财务管理专家系统是财务管理知识、经验和技 能的程序系统,用来求解财务领域内的各种问题。 具体地说,财务管理专家系统主要用来代替财务 管理专家作复杂财务管理过程描
当今时代,随着科学技术不断发展,计算机已成为处理信息的主要工具之一。掌握计算机的基础知识和基本操作技能是科学发展和走向未来信息化时代的需要。下面是我为大家整理的
计算机技术的应用及发展探究论文 摘要: 随着现代社会全球化、信息化发展的速度加快,计算机技术获得了更广阔的发展空间,被越来越多的应用在生活生产中的方方面面,计算