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Neurofuzzy: A Different Type of Neural Nets
-- Zaptron's High-Order Nonlinear Neural Networks

|Fuzzy logic|Neural Networks|Neurofuzzy|
|High-order Nonlinear Neural Networks|DataX|

Fuzzy Logic
What is fuzzy logic - Fuzzy inference  (or simply "fuzzy logic") is a powerful problem-solving methodology with wide applications in industrial control and information processing. It provides a simple way to draw definite conclusions from vague, ambiguous or imprecise information. It resembles human decision making with its ability to work from approximate data and find precise solutions.

Unlike classical logic which requires a deep understanding of a system, exact equations and precise numeric values, fuzzy logic incorporates an alternative way of thinking, which allows modeling complex systems using a higher level of abstraction originating from our knowledge and experience. Fuzzy Logic allows expressing this knowledge with subjective concepts such as "very good" and "a little bit satisfied" which are mapped into exact numeric ranges.

How does fuzzy logic work - it uses 3 simple steps defined below

fuzzification - to convert numeric data (e.g., $24.50 in sales) in real-world domain to fuzzy numbers in fuzzy domain

aggregation (rule firing) - computation of fuzzy numbers (all between 0.0 and 1.0) in fuzzy domain

defuzzification - convert the obtained fuzzy number back to the numeric data (e.g. 150.34% in total profitability) in the real-world domain.

Fuzzy logic advantages:

mimic human decision making to handle vague concepts
rapid computation due to intrinsic parallel processing nature
ability to deal with imprecise or imperfect information
resolving conflicts by collaboration, propagation and aggregation
improved knowledge representation and uncertainty reasoning
modeling of complex, non-linear problems
natural language processing/programming capability

Fuzzy logic limitations:

highly abstract and heuristic
need experts for rule discovery (data relationships)
lack of self-organizing & self-tuning mechanisms of NN

 

Neural Networks (NN)
Neural networks are modeless systems that learn from the underlying relationships of data. They are organized in a way to simulate the cells of human brain.
Advantages of NN
no need to know data relationships
self-learning capability
self-tuning capability
applicable to model various systems

Limitations of NN (some say NN is a "garbage in garbage out" system)
unable to handle linguistic information
unable to manage imprecise or vague information
unable to resolve conflicts
unable to combine numeric data with linguistic or logical data
difficult to reach global minimum even by complex BP learning
rely on trial-and-errors to determine hidden layers and nodes

 

Neurofuzzy Techniques
Neurofuzzy refers to the combination of fuzzy set theory and neural networks with the advantages of both:
handle any kind of information (numeric, linguistic, logical, etc.)
manage imprecise, partial, vague or imperfect information
resolve conflicts by collaboration and aggregation
self-learning, self-organizing and self-tuning capabilities
no need of prior knowledge of relationships of data
mimic human decision making process
fast computation using fuzzy number operations

 

ZAPTRON's Proprietary Technology -- High-Order Nonlinear Neural Networks.

Unlike classical, linear neural networks, the proprietary High-Order Nonlinear Neural Networks (HONLNN) by ZAPTRON have the following outstanding features:
Self-organizing ability: HONLNN traces model changes or variations (such as business rule, relationship or regulation changes). For given data the HONLNN system can automatically organize itself as an optimal model for the data, without human interaction.  This means, the number of hidden layers and the number of nodes on each layer are determined by the HONLNN itself, a significant improvement over the backward propagation (BP) networks.

Nonlinearity - the inter-node effect is added to each node's output, giving better approximation than that by linear networks.

Modeling of fuzzy information - fuzzy set theoretical method is incorporated in HONLNN to allow modeling of quantitative information expressed by linguistic or logical data, such as human, natural or environmental factors in finance and business management.

Fusion of incompatible information - HONLNN uses fuzzy log   to offer a way for combining numeric data with linguistic or logical data to achieve information propagation and knowledge aggregation.

Super-fast computation: input data are first transferred by a high-order nonlinear module before being used in NN learning.  By the equivalence of NN and Fourier series, a super-fast, real-time NN is thus produced.

Incorporating GMDH (Group Method for Data Handling): GMDH is a high-order, nonlinear method in system model identification.  Like Fourier series, GMDH can approximate any function with good accuracy.

Genetic algorithm-based generation - network layers and nodes are generated iteratively by genetic programming, giving the best solution.

Achieve global minimum quickly by using fewer layers

Applications of Neurofuzzy Technology
Business rule extraction and explanation process
Incorporation of personal preference
Model building
Fusion of numeric data and linguistic information

Tools in DataX™ Software Suite
Build business models
Market simulations
Model Validations
Fuzzy time series forecasting

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Copyright © 1997-2000 ZAPTRON Systems, Inc. Updated January 26, 1999