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1.
从逻辑哲学观点看,在"符号化、公理化的模糊逻辑"与形式化的"人脑使用的模糊逻辑"(苗东升的说法)这两者之间,只是形式模型及其现实原型的关系,决不相互排斥.真正的问题不在于,现实生活中人脑所使用的实际上行之有效的模糊推理,是否应该和可能符号化、公理化,而是在于如何恰当地进行形式化.笔者采用苏珊·哈克(Susan Haack)的逻辑哲学观点,认为非经典逻辑可划分为扩展逻辑和异常(deviation)逻辑,模糊逻辑归属于异常逻辑.本文以模糊逻辑系统FZ为例,具体分析了虽然经典逻辑中一些较强的公理和推理规则均不成立,但是与之对应的较弱的"合经典的"(well-behaved)公理和推理则却仍然可以成立,由此导致一系列新奇性质.笔者采用了达·柯斯塔(da Costa)的形式化技巧,它是关睛"在虚设不矛盾律成立的前提下"(相应公式可以称为"合经典的")才能成立的逆否律.当我们撤除了"虚设不矛盾律为前提"的限定,它又重新回到了无条件成立的情况.笔者也推广了玻尔(N.Bohr)和冯·威扎克(von Weizsaecker)关于对应原理的思想,认为作为非经典逻辑的模糊逻辑与经典逻辑之间也应当遵守"对应原理":经典逻辑是模糊逻辑的前身,模糊逻辑将构成更为普遍的逻辑形式,经典逻辑作为模糊逻辑的极限形式,在局部情况下还保持自身的意义.  相似文献   

2.
论模糊逻辑的有效性   总被引:1,自引:0,他引:1  
为了符合经典有效性标准,我国学者王国俊教授和婓道武教授分别构造了模糊形式演绎系统L*和模糊谓词一阶形式系统K*,这反驳了模糊逻辑缺乏逻辑基础的谬论。然而随着现代科学日益进步和逻辑学分支学科的不断发展,经典逻辑过于狭隘的非此即彼的模式及其有效性标准显得越来越过时了。非形式逻辑通过对经典有效性标准的限制和修改,已形成归纳有效性、实质有效性等另类的有效性概念。模糊逻辑用发展了的有效性标准来评估更能体现其理论存在的价值和自身特点。  相似文献   

3.
针对工业调节阀中广泛存在的时滞现象,提出一种基于模糊原理的带有Smith预估器的智能阀门定位器控制方法。分析智能阀门定位器的结构和原理,通过设计Smith预估器补偿滞后时间,实现超前响应,克服时滞对系统性能的影响;通过模糊控制与PID控制结合,设计调整模糊规则,实现控制器参数的自整定。两者结合构成模糊Smith方法,提高了系统的动静态性能。模糊内模控制器对克服时滞、提高系统性能有良好的效果,将模糊Smith器与模糊内模控制器及PID控制器进行仿真研究对比。仿真结果表明,模糊Smith控制方法比模糊内模控制方法和传统PID方法更能有效地提高调节阀的快速性,克服时滞,改善系统性能。  相似文献   

4.
针对目前的扩展模糊描述逻辑缺乏TBox约束下的推理算法,提出TBox约束下扩展模糊描述逻辑EFALC截概念可满足性问题及其推理算法.该算法的设计参考用于经典描述逻辑的tab-leau算法;详细描述了EFALC的转化规则和推理算法的过程,并使用递归函数调用、分支裁减和引入中间结果集合这3种技术对算法进行优化.证明了该优化推理算法的最坏时间复杂性为指数,且具有完备性和正确性,同时证明了TBox约束下EFALC截概念可满足性问题的复杂性是指数时间完全的.  相似文献   

5.
轧机厚度控制系统是轧机最重要的部分之一。本文利用MATLAB模糊逻辑工具箱,建立了以辊缝位置为被控对象的参数自调节模糊PID厚度自动控制系统模型,对轧机自动控制系统进行模糊PID控制。仿真结果表明:模糊PID控制器控制误差小,适应范围广,可以满足生产要求。模糊PID控制技术为解决厚度自动控制提供一种有效途径,同时也为现代工业自动控制问题提供了新的解决方案。  相似文献   

6.
本文研究了一种新的基于模糊层次聚类与模糊推论技术的模糊信息检索方法。该方法通过对文件的聚类、构建模糊集群文件、建立集群中心文件的模糊逻辑规则来修改用户的查询信息,使查询结果更加符合用户的需求。这种模糊信息检索方法因为能够扩展用户的查询条件来使用一种更有效率的方式进行模糊检索,所以比现有的方法更加灵活化和智能化。  相似文献   

7.
评标过程中由于确定因素和模糊因素并存,应用现行评标方法,评标专家难以在较短时间里对模糊因素做出较准确的评判。为此,将模糊集合理论的思想和方法引入评标过程,首先提出了适合矿井建设项目的评标指标体系;其次建立了矿井建设工程项目评标模糊综合评价模型,最后给出具体实例予以验证。结果表明,提出的评标方法能够快速、有效、准确地选定最优投标方。  相似文献   

8.
水污染指数的模糊综合评价模型   总被引:1,自引:0,他引:1  
利用因素之间的相似性矩阵的最大特征值对应的特征向量确定因素的权重,建立水污染指数的模糊综合评价模型.该模型用国家水质评价标准确定权重,避免了评价结果的主观性.实验结果表明该模型可得到与其它经典方法相同的评价结果.  相似文献   

9.
在工业控制中,温度是一种很难被控制的被控对象.经典控制很难完成对这种系统的控制,因此需要一种智能化控制方法对温度进行控制.本文提出利用粒群优化模糊PID参数的方法来实现对温度的控制,仿真研究表明该控制方法在控制中表现出良好的效果.  相似文献   

10.
带模糊约束线性规划的关键是如何将其转化为经典的线性规划加以求解,文中基于Werners提出的Max-Min方法,通过对目标函数及约束条件的隶属函数进行加权,建立了一个新的(LP)模型,该方法从理论上证明了其解的模糊有效性,并用实例证明新模型下的解更有效.  相似文献   

11.
《海外英语》2007,(5):44-45
It is worthy of noting that, whilst Crookston Castle witnessed the earlier and happier portion of Mary's variegated life,  相似文献   

12.
《海外英语》2007,(4):36
There are numbers of crossroads on our long and unpredictable life journey where we totally have no idea about which direction to choose. No matter what our decision is, we should not turn back, but face the music and go ahead instead. I am this kind of girl who always does try without regretting, one example is how I dealt with my love.  相似文献   

13.
王菲 《华章》2007,(12):273-273
Migration occurs behind a variety of reasons and has a great effect on the whole world. People may migrate in order to improve their economic situation, or in order to escape civil strife, persecution, and environmental disasters. The impact of migration is complex, bringing both benefits anddisadvantages. This paper briefly talks about the causes of migration, the allocation of benefits, and the ways in which individual countries and the international community deal with this important subject.  相似文献   

14.
裴水妹 《华章》2007,(11):196
Sister Carrie is one of the most controversial characters in American literature.Thought as a "fallen woman" firstly,she was defined as a "new woman" by some critics later. However, by digging into the motivaton behind the whole process of Carrie's "success", the relationship between Carrie and her creator (the author), the social conditions of then American, it can be found that Carrie has never been free-standing on her thought and she has never found her real-sdf even after becoming a famous actress. In a society dominated by mass consumerism Carrie is only an adherent of her own desires. She also is a representative of all those country girls flooded into cities, a symbol and a sacrifice of the urbanization of America in a time countryside was overcome by cities.  相似文献   

15.
16.
1.IntroductionOne-cyclecontrolmethod,whichwasproposedaboutonedecadeago[1],hasbecomeanattractivemethodinspecialfieldssuchaspowerfactorcorrection[2-6],switchingamplifiers[7,8],etc.Themainideaofthiscontrollerisbasedonintegrationofdiodevoltageinone-cycleandforcesittobeexactlyequaltothereferencevalue.Themainadvantageofthiscontrollerisitsrealtimeabilitytorejectthevariationofinputvoltage[1].Despitethisgreatability,ithasnogoodperformancesinrejectingofloaddisturbanceandfollowingreferencecommands.Espec…  相似文献   

17.
Today, Sunday morning, I sit thinking and typing at my computer. My thoughts are in my homeland, India and my body is in China. The body is here and mind there for a good reason. Mr. Hu is president and I am resident and both are in each other's countries (what a difference the absence of one small letter makes!). Mr. Hu will return in a few days and I will stay on longer.  相似文献   

18.
STORIES     
正A One day a pig went to the stable(马棚)to see his good friend,an oldhorse,and was going to stay there forthenight.Night came and it was time forsleep.The pig went into the straw heap(稻草堆)and lay comfortably.A longtime passed,but the horse was stillstanding there and did not move.Thepig asked the horse why he did not go tosleep."Standing like this is the begin-ning ofsleeping,"answered the horse.  相似文献   

19.
正1.Any fool can count the seeds in an apple.Only God can count all the apples in one seed.2.Happy families are all alike;every unhappy family is unhappy in its own way.3.Memories are the key not to the past,but to the future.4.Sometimes in the dark you see what you want to see.5.There is a great difference between  相似文献   

20.
正Scope and Policy The Journal of Chongqing University-English Edition(JCQU-E)is a peerreviewed journal publishing research articles in multiple disciplines of science and technology,covering civil and environmental engineering,chemical engineering,biotechnology,mechanical and electrical engineering,computer and data processing,mining,metallurgy,materials science,and interdisciplines thereof.  相似文献   

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