在欣欣向荣的中国南部城市深圳诞生的这台超级计算机被命名为“星云”(Nebulae)，星云是产生恒星的气体云。这台机器代表着中国在技术上挑战美国和其他发达国家的雄心壮志，但同时也凸显出中国成就的局限。
过去两年，中国在开发超级计算机方面所取得的出人意料的进展引起了美国的焦虑。超级计算机是现代科学的大脑，也是经济发展的引擎，而美国一直是这一领域无可争议的领跑者。中国在计算方面取得的进步对于中国建造宇宙飞船和先进战斗机的能力，以及中国在遗传学上的日益增长的实力至关重要。根据俄亥俄州哥伦布市的巴特尔纪念研究所(Battelle Memorial Institute)的数据，中国在2010年超过日本，成为研发投资第二多的国家。尽管中国在研发方面的支出仍远远落后于美国，但已经取得了长足的进展。
但是仔细观察就会发现，中国的超级计算机项目并没有像许多人认为的那样，对美国在技术上的领先地位造成威胁。中国的研究人员说，如何使用超级计算机通常由当地政府官员决定，而与突破性技术相比，当地政府官员对当地发展项目更有兴趣。
中国的官员同时也没有弄清楚如何实施与美国或欧洲的标准接近的项目。中国的科学家缺乏资金和自由，难以研究没有政府支持的技术，这样他们就可能落后于技术前沿。
结果就是，中国的超级计算机工程没有产生能够创造新产业的技术突破。相反，政府部署这些工程的目的仅仅是是帮助国家追上欧美，无论是在医疗保健领域、汽车设计还是航空领域。这对于经济发展至关重要，但是也提醒人们，中国仍然是发展中国家，其主要目标仍然是缩小同更富裕国家在经济和技术上的差距。
从事中国高级电脑项目开发工作长达数十年的北京航空航天大学研究员钱德沛说，我们的战略从来不是引领，而是跟随。因为这是经济效率最高的发展。
俄勒冈大学(University of Oregon)中国科学政策专家萨特梅尔(Richard Suttmeier)说，中国还没有弄清楚开拓新技术的正确方法，部分原因是研究人员的待遇取决于他们发表学术论文的数量，而不是他们工作的质量和创新。
在中国，超级计算机在很大程度上被看作是各地用来发展地方经济的工具。中国各地的市政府在制定超级计算机研发议程方面所发挥的作用远远超过美国市政府，因为这类项目的资金大多来自财政拨款。
深圳一家为“星云”研发应用程序的研究所的副所长冯圣中说，深圳并不关心气候变化和天体物理学(这些都是超级计算机的传统研究项目)，他们关心的是当地的问题。造价13亿美元的国家超级计算深圳中心有四分之三的投资来自深圳市政府。
冯圣中目前正在制定一个利用“星云”改善华南地区医疗服务的计划。改善医疗服务是一个有着重要社会意义的目标，但并非要利用运算速度居世界第四的超级计算机才能实现。
世界500台最快的超级计算机（每秒可进行数万亿次运算）中，74台为中国所有，而2007年中国只有10台。中国在这方面取得的飞速进展在一定程度上要归功于计算机设计的改变。
上世纪80年代，位于美国明尼阿波利斯的克雷研究公司(Cray Research)是全球超级计算机技术的领导者，当时这种计算机由几个功能非常强大的处理器驱动，而这些处理器在设计上有相当的难度。而且当时有很严格的出口管控。从90年代开始，超级计算机研发人员开始把数以万计的现成的微处理器连在一起，来执行单项任务。中国可以从英特尔公司(Intel Corp.)、高级微设备公司(Advanced Micro Devices Inc.)和其它公司购买这些计算机芯片，制造自己的计算机。
分析人士说，中国科学家曾在欧美顶级计算机中心接受培训，这令他们受益匪浅，此外他们还可获得来自海外的计算机芯片和其它零部件以及中国政府持续不断的资金保证和支持。研发超级计算机的努力不仅没有遭遇有关中国人盗窃外国技术的指控，反而有中国科学家说，美国对部分高科技产品实施出口限制让他们加倍努力进行自主研发。
尽管如此，中国在很大程度上仍然依靠美国生产的微处理器（即计算机的大脑），因此落后于领先水平。中国曾开发出一台使用国产微处理器的计算机，但这台计算机不运行商业软件。另外一个正在开发中的微处理器“龙芯”(Loongson)将使用现有软件，并可能最终成为英特尔等的竞争对手。
中国的一些超级计算机一直被用来设计中国隐形战斗机机翼（目前正处于测试阶段）以及中国首架商用飞机的部件。在这两个领域，中国都远远落后于美国。
在深圳，预计“星云”将用于改进暴风雨预警系统，并帮助医疗公司寻找致病原因。不过，它也将被用于更简单的任务，比如处理视频动画。目前“星云”仍处于测试阶段。
总部位于马萨诸塞州弗拉明哈姆(Framingham)的市场研究公司国际数据公司(IDC)超级计算机分析师康威(Steve Conway)说，在美国，各市和各州都向当地超级计算机中心提供资金，但通常在设定超级计算机任务上没有什么话语权。美国的超级计算机中心几乎总是专注于先进科学研究，比如为个人量身设计的药物。
尖端技术的研究风险很高，但可以带来巨大回报，使中国等竞争对手望尘莫及。俄勒冈大学的萨特梅尔说，美国的警惕性并非总是有根据的，重要的一点是不断制定战略，以便使美国在竞争中遥遥领先。
中国最大的劣势之一是软件开发，这个问题可能会带来破坏性的影响，因为超级计算机的有用与否取决于应用软件的质量。中国的研究员说，只有不到10%的超级计算机经费被用于开发应用软件。研究员抱怨说，政界领导人敦促他们建造能够引发媒体轰动的新型超级计算机，而不是专注于超级计算机是否发挥了全部功能。
美国在超级计算机上的投入约为中国的六倍。在美国，软件开发预算为硬件预算的约30%。计算机专家们说，就算是这个水平也不够。
中国科学家说，在中国，争夺软件开发资金的大战非常激烈，在长期软件项目上，研究员很少以团队的形式进行。
为形像地说明外界对中国超级计算机工作的偏颇看法，资深超级计算机研究员钱德沛把手掌放到屁股的位置。他说，一般来讲，我们处于这个水平，但所有人都认为我们要更高。他一边将手掌抬到肩膀的高度。
专升本考试通过之后的本科毕业论文需要撰写的字数与正常的本科生相同，都是在1万字以上。通常情况下，专升本考试通过的学生一般被认为是本科生之一，因此他们的毕业论文撰写标准与其他人相比并没有明显的区别，都是在1万字以上。
常规的价格区间在1000-3000不等。
计算机毕业设计，根据程序的难易程度，工作量等不同，因此，价格会有差别。
靠谱的都是代码保证你运行通过，代码给你讲解明白，原理给你写清楚，还能教给你怎样写作，让你顺顺利利写完，我就接触过一个同学，用一千多买了一个程序回来，不仅没达到想要的效果，还被原来的卖主抛弃了，后来花几百块找我帮她继续完成……
无论哪个专业，几百块说给你定做的基本都是骗子。
计算机程序，要知道，它的环境配置不同数据库不同等，稍微有点出入也就不能运行了。
至于论文，每个学校要求的字数不一样，而且。查重的范围以及标准所用的查重系统等都有所区别，因此这个价格也是不同的.。
更何况，目前，本科论文还有次年的抽检，不过是要撤销学位证书的。
总之一句话，不要贪小便宜。
A computer is a machine that manipulates data according to a list of instructions.
The first devices that resemble modern computers date to the mid-20th century (1940–1945), although the computer concept and various machines similar to computers existed earlier. Early electronic computers were the size of a large room, consuming as much power as several hundred modern personal computers.Modern computers are based on tiny integrated circuits and are millions to billions of times more capable while occupying a fraction of the space. Today, simple computers may be made small enough to fit into a wristwatch and be powered from a watch battery. Personal computers, in various forms, are icons of the Information Age and are what most people think of as "a computer"; however, the most common form of computer in use today is the embedded computer. Embedded computers are small, simple devices that are used to control other devices — for example, they may be found in machines ranging from fighter aircraft to industrial robots, digital cameras, and children's toys.
The ability to store and execute lists of instructions called programs makes computers extremely versatile and distinguishes them from calculators. The Church–Turing thesis is a mathematical statement of this versatility: any computer with a certain minimum capability is, in principle, capable of performing the same tasks that any other computer can perform. Therefore, computers with capability and complexity ranging from that of a personal digital assistant to a supercomputer are all able to perform the same computational tasks given enough time and storage capacity.
History of computing
Main article: History of computer hardware
The Jacquard loom was one of the first programmable devices.It is difficult to identify any one device as the earliest computer, partly because the term "computer" has been subject to varying interpretations over time. Originally, the term "computer" referred to a person who performed numerical calculations (a human computer), often with the aid of a mechanical calculating device.
The history of the modern computer begins with two separate technologies - that of automated calculation and that of programmability.
Examples of early mechanical calculating devices included the abacus, the slide rule and arguably the astrolabe and the Antikythera mechanism (which dates from about 150-100 BC). Hero of Alexandria (c. 10–70 AD) built a mechanical theater which performed a play lasting 10 minutes and was operated by a complex system of ropes and drums that might be considered to be a means of deciding which parts of the mechanism performed which actions and when.This is the essence of programmability.
The "castle clock", an astronomical clock invented by Al-Jazari in 1206, is considered to be the earliest programmable analog computer.It displayed the zodiac, the solar and lunar orbits, a crescent moon-shaped pointer travelling across a gateway causing automatic doors to open every hour,and five robotic musicians who play music when struck by levers operated by a camshaft attached to a water wheel. The length of day and night could be re-programmed every day in order to account for the changing lengths of day and night throughout the year.
The end of the Middle Ages saw a re-invigoration of European mathematics and engineering, and Wilhelm Schickard's 1623 device was the first of a number of mechanical calculators constructed by European engineers. However, none of those devices fit the modern definition of a computer because they could not be programmed.
In 1801, Joseph Marie Jacquard made an improvement to the textile loom that used a series of punched paper cards as a template to allow his loom to weave intricate patterns automatically. The resulting Jacquard loom was an important step in the development of computers because the use of punched cards to define woven patterns can be viewed as an early, albeit limited, form of programmability.
It was the fusion of automatic calculation with programmability that produced the first recognizable computers. In 1837, Charles Babbage was the first to conceptualize and design a fully programmable mechanical computer that he called "The Analytical Engine". Due to limited finances, and an inability to resist tinkering with the design, Babbage never actually built his Analytical Engine.
Large-scale automated data processing of punched cards was performed for the U.S. Census in 1890 by tabulating machines designed by Herman Hollerith and manufactured by the Computing Tabulating Recording Corporation, which later became IBM. By the end of the 19th century a number of technologies that would later prove useful in the realization of practical computers had begun to appear: the punched card, Boolean algebra, the vacuum tube (thermionic valve) and the teleprinter.
During the first half of the 20th century, many scientific computing needs were met by increasingly sophisticated analog computers, which used a direct mechanical or electrical model of the problem as a basis for computation. However, these were not programmable and generally lacked the versatility and accuracy of modern digital computers.
A succession of steadily more powerful and flexible computing devices were constructed in the 1930s and 1940s, gradually adding the key features that are seen in modern computers. The use of digital electronics (largely invented by Claude Shannon in 1937) and more flexible programmability were vitally important steps, but defining one point along this road as "the first digital electronic computer" is difficult (Shannon 1940). Notable achievements include:
EDSAC was one of the first computers to implement the stored program (von Neumann) architecture.Konrad Zuse's electromechanical "Z machines". The Z3 (1941) was the first working machine featuring binary arithmetic, including floating point arithmetic and a measure of programmability. In 1998 the Z3 was proved to be Turing complete, therefore being the world's first operational computer.
The non-programmable Atanasoff–Berry Computer (1941) which used vacuum tube based computation, binary numbers, and regenerative capacitor memory.
The secret British Colossus computers (1943), which had limited programmability but demonstrated that a device using thousands of tubes could be reasonably reliable and electronically reprogrammable. It was used for breaking German wartime codes.
The Harvard Mark I (1944), a large-scale electromechanical computer with limited programmability.
The U.S. Army's Ballistics Research Laboratory ENIAC (1946), which used decimal arithmetic and is sometimes called the first general purpose electronic computer (since Konrad Zuse's Z3 of 1941 used electromagnets instead of electronics). Initially, however, ENIAC had an inflexible architecture which essentially required rewiring to change its programming.
Several developers of ENIAC, recognizing its flaws, came up with a far more flexible and elegant design, which came to be known as the "stored program architecture" or von Neumann architecture. This design was first formally described by John von Neumann in the paper First Draft of a Report on the EDVAC, distributed in 1945. A number of projects to develop computers based on the stored-program architecture commenced around this time, the first of these being completed in Great Britain. The first to be demonstrated working was the Manchester Small-Scale Experimental Machine (SSEM or "Baby"), while the EDSAC, completed a year after SSEM, was the first practical implementation of the stored program design. Shortly thereafter, the machine originally described by von Neumann's paper—EDVAC—was completed but did not see full-time use for an additional two years.
Nearly all modern computers implement some form of the stored-program architecture, making it the single trait by which the word "computer" is now defined. While the technologies used in computers have changed dramatically since the first electronic, general-purpose computers of the 1940s, most still use the von Neumann architecture.
Microprocessors are miniaturized devices that often implement stored program CPUs.Computers that used vacuum tubes as their electronic elements were in use throughout the 1950s. Vacuum tube electronics were largely replaced in the 1960s by transistor-based electronics, which are smaller, faster, cheaper to produce, require less power, and are more reliable. In the 1970s, integrated circuit technology and the subsequent creation of microprocessors, such as the Intel 4004, further decreased size and cost and further increased speed and reliability of computers. By the 1980s, computers became sufficiently small and cheap to replace simple mechanical controls in domestic appliances such as washing machines. The 1980s also witnessed home computers and the now ubiquitous personal computer. With the evolution of the Internet, personal computers are becoming as common as the television and the telephone in the household.
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