【導(dǎo)讀】歡迎進(jìn)入模糊邏輯的精彩世界，你可以用新科學(xué)有力地實(shí)現(xiàn)一些東西。除此之外的其他人與物無(wú)法做到的事情。得越來(lái)越難，最終變得無(wú)法闡述。于是，終于到達(dá)了一個(gè)只有靠人類發(fā)明的模糊邏。程發(fā)展的時(shí)間；有時(shí)，在一些高度復(fù)雜的系統(tǒng)中，這是唯一可以解決問(wèn)題的方法。1963年，扎德博士成為加州大學(xué)伯克利分校電氣工程學(xué)院院長(zhǎng)。扎德博士認(rèn)為模糊控制是那時(shí)的熱點(diǎn)，不是以后的熱點(diǎn)，更不應(yīng)該受到輕視。目前已經(jīng)有了成千上萬(wàn)基于模糊邏輯的產(chǎn)品，從聚焦照相機(jī)到?？梢愿鶕?jù)衣服臟度自我控制洗滌方式的洗衣機(jī)等。如果你在美國(guó)，你會(huì)很容易找到。想一想，當(dāng)通用汽車告訴大眾，她生產(chǎn)的汽車其反剎車是根據(jù)模。糊邏輯而造成的時(shí)候，那會(huì)對(duì)其銷售造成多么大的影響。將車速控制在48M，他們用的就是模糊推理。你在城鎮(zhèn)中駕駛車輛的這個(gè)模糊推理能力，也曾被我們的祖先用于獲得食物，并且綜合它們而得到最好的行為方式。其當(dāng)一個(gè)非專業(yè)人士來(lái)主持重大工程項(xiàng)目的時(shí)候。

　　

【正文】 speed, very high speed, real slow speed, excessively high accelerator setting, accelerator setting about right, etc. A fuzzy variable bees a linguistic variable when we modify it with descriptive words, such as somewhat fast, very high, real slow, etc. The main function of linguistic variables is to provide a means of working with the plex systems mentioned above as being too plex to handle by conventional mathematics and engineering formulas. Linguistic variables appear in control systems with feedback loop control and can be related to each other with conditional, ifthen statements. Example: If the speed is too fast, then back off on the high accelerator setting. Universe of Discourse Let us make women the object of our consideration. All the women everywhere would be the universe of women. If we choose to discourse about (talk about) women, then all the women everywhere would be our Universe of Discourse. Universe of Discourse then, is a way to say all the objects in the universe of a particular kind, usually designated by one word, that we happen to be talking about or working with in a fuzzy logic solution. A Universe of Discourse is made up of fuzzy sets. Example: The Universe of Discourse of women is made up of professional women, tall women, Asian women, short women, beautiful women, and on and on. The World39。s First Fuzzy Logic Controller， In England in 1973 at the University of London, a professor and student were trying to stabilize the speed of a small steam engine the student had built. They had a lot going for them, sophisticated equipment like a PDP8 miniputer and conventional digital control equipment. But, they could not control the engine as well as they wanted. Engine speed would either overshoot the target speed and arrive at the target speed after a series of oscillations, or the speed control would be too sluggish, taking too long for the speed to arrive at the desired setting, The professor, E. Mamdani, had read of a control method proposed by Dr. Lotfi Zadeh, head of the electrical engineering department at the University of California at Berkeley, in the United States. Dr. Zadeh is the originator of the designation fuzzy, which everyone suspects was selected to throw a little pie in the face of his more orthodox engineering colleagues, some of whom strongly opposed the fuzzy logic concept under any name. Professor Mamdani and the student, S. Assilian, decided to give fuzzy logic a try. They spent a weekend setting their steam engine up with the world39。s first ever fuzzy logic control system ....... and went directly into the history books by harnessing the power of a force in use by humans for 3 million years, but never before defined and used for the control of machines. The controller worked right away, and worked better than anything they had done with any other method. The steam engine speed control graph using the fuzzy logic controller appeared 。 As you can see, the speed approached the desired value very quickly, did not overshoot and remained stable. It was an exciting and important moment in the history of scientific development. The Mamdani project made use of four inputs: boiler pressure error (how many temperature degrees away from the set point), rate of change of boiler pressure error, engine speed error and rate of change of engine speed error. There were two outputs: control of heat to the boiler and control of the throttle. They operated independently. A fuzzy logic system does not have to include a continuous feedback control loop as in the above described Mamdani system in order to be a fuzzylogic system, an impression you might receive from reading much of the fuzzy logic literature. There could be continuous feedback loop control, a bination of feedback loop control and onoff control or onoff control alone. A fuzzy logic control system could be as simple as: If the motor temperature feels like it is too hot, turn the motor off and leave it off. Or, If the pany39。s president and all the directors just sold every share of stock they own, then WE sell! A fuzzy logic system does not have to be directed toward electromechanical systems. The fuzzy logic system could be, for example, to provide buysell decisions to trade 30 million US dollars against the Japanese yen. Fuzzy logic controllers can control solenoids, stepper motors, linear positioners , etc., as well as, or concurrently with, continuous feedback control loops. Where there is continuous feedback control of a control loop, the response for varying degrees of error can be nonlinear, tailoring the response to meet unique or experience determined system requirements, even anomalies. Controllers typically have several inputs and outputs. The handling of various tasks, such as monitoring and manding a control loop and monitoring various inputs, with mands issued as appropriate, would all be sequenced in the puter program. The program would step from one task to the other, the program receiving inputs from and sending mands to the converter/controller. Inputs for a fuzzy logic controlled mechanical/physical system could be derived from any of thousands of real world, physical sensors/transducers. The Thomas Register has over 110 pages of these devices. Inputs for financial trading could e from personal assessments or from an ASCII data munication feed provided by a financial markets quote service. Progress in Fuzzy Logic， From a slow beginning, fuzzy logic grew in applications and importance, until now it is a significant concept worldwide. Intelligent beings on the other side of our galaxy and throughout the universe have probably noted and defined the concept. Personal puter based fuzzy logic control is pretty amazing. It lets novices build control systems that work in places where even the best mathematicians