Theoretical And Experimental Research On Uncertainty Based On Cloud Model

Uncertainty research has become a research subject of academia, which has been widely used. For example, probability theory which describes the law of random uncertainty has become a tool for describing micro material world; Fuzzy mathematics which describes the law of fuzzy uncertainty has become a powerful tool for artificial intelligence computing.Cloud model theory proposed by academician Deyi.Li is a new method which is used for transforming qualitative to qualitative based on the randomness and fuzziness theory. It is widely used in many fields, however, why it has been set up, and whether there is any objective experimental basis is still a problem to be solved. In this thesis, we give an objective experiment for cloud model theory. The experiment verifies that as random experiment for probability and membership experiment for fuzzy, cloud model also has its experimental basis, it is a theory established on the existence of fuzzy’s fuzzy phenomena, random’s fuzzy phenomena and fuzzy’s random phenomena.This thesis uses a typical fuzzy concept "young people" as the research object, through a new statistical method, get the cloud model of the "young people" concept, verify objective existence of cloud model, besides,conclude some meaningful conclusions that haven’t been given. Through "young people" age range questionnaire survey on more than one thousand three hundred people which are from different age groups, we got much real and effective data. Then the data should be preprocessed, calculated and analyzed until get conclusions. Besides, this thesis also discusses its future application field. The thesis’ s main innovation points are:1. Comprehensive coverage of all ages. Investigated from kindergarten, first grade, second grade...to undergraduate, postgraduate and old college students, about 1306 people, a total of 13 classes, age structure more comprehensive, more investigation number. Experimental questionnaire form was designed with two versions of the random sequence form from 1 to 64, this method has two advantages: firstly, with two different versions alternately given to the investigators, smaller age investigators cannot copy each other’s questionnaire, then, the data is reliable and effective. Second, each person’s concept on each age can be observed clearly as well as the fuzzy degree of certain ages.2. Statistics found that the membership functions of "young people" the concept by people with different ages have a range of drift, which is consistent with the cloud model theory, proves the cloud model has a solid experimental basis.3. The experimental results show that for each one the fuzzy concept of "young people" is not a born concept. Kindergarten stage(about 4 to 8 years old or so), people have no right complete concept of "young people", and with time going on the right concept can be established.4. Find cloud model of "young people" is an asymmetric structure which distributed densely on the left side and loosely on the right.5. From the experimental data to its cloud model, it gives the parameters of the cloud generator and backward cloud generator, and discusses its application in practice, for example, it can be used to determine the membership function of fuzzy control.People of different ages may have different judge on fuzzy concepts. This research fills the blank of the experimental study of this point, proves that the cloud model has objective experimental basis, and put forward the experimental standard for application of membership function selection, in the meanwhile, it provides a reference basis for the future research in this direction.