THE LEARNING PROCESS

We learn from data. Therefore, the way we prepare the data for the learning process will crucially condition the quality of learning and the reliability of the extracted knowledge. 

The quality and the relationship of the data to the information and knowledge are crucial points in the learning process... 

Just like humans, ANNs learn from examples. The examples are delivered as input data. The learning process of an ANN is called training. In the human brain, the synaptic connections, and thus the connections between the neurons. 

Classification describes the process of assigning an instance or property to one of several given classes. The classes are defined beforehand and this class assignment is used in the learning process, which is therefore supervised. Statistical methods and decision trees (cf. Section 9.3) are also widely used for classification tasks. 

The structure of a neural network forms the basis for information storage and governs the learning process. The type of neural network used in this work is known as a feed-forward network the information flows only in the forward direction, i.e., from input to output in the testing mode. A general structure of a feed-forward network is shown in Fig. I. Connections are made be-... 

In different places in the outlines of teachers reflective diaries there are statements indicating that students interest in learning about chemical reactions has increased in comparison to previous years. Teachers mentioned the increase of students interest in the context of all three main factors that are incorporated in the LON approach, i.e. (1) Eveiyday life situations as the foundation of the learning process. (2) The learning process involves many students activities. (3) Chemical reactions are consistently presented in all three types of representation. Consequently, we assnme that those three factors are the main reasons for the increased interest of students in learning about chemical reactions. Each of the listed factors is described in detail below ... 

Everyday life situations are the foundation of the learning process Stndents understood that chemical reaction go on in everyday life and are therefore of interest to them. That point seemed to be important to all of the participating teachers since in many places in their reflective diaries they made statements like e.g. ... 

The learning process involves many students"activities Students interest increased because they liked playing an active role in the learning process (e.g. hands on experiments, constraction of representations of chemical reactions with the use of models). Those who were not used to such an approach from earlier teaching also improved their experimental skills and gained experiences through the work with models. In the reflective diaries of all the teachers, statements to support this point could be found as follows ... 

Some tasks in the Test of Gained Knowledge required students to connect observations about the macro course of chemical reactions with their notations in the submicro and/or symbolic types of representation. The results indicate that most students were able to rearticulate the information about reactants and products of a chemical reaction from the textual description of chemical reaction into the form of word chemical equation (textual description of macros word equation of macro Task 8.2, f(o/ )=89.82% Task 9.1, f(o/ )=87.61%). This action corresponds to the first step in learning to write down chemical equation in the LON approach. It can easily be explained, because teachers described the learning process to be very efficient to this point, as is illustrated below ... 

Students interest in learning about chemical reactions increased, which is due to three main factors that ate incorporated in the LON approach (1) Everyday life situations ate the foundation of the learning process. (2) The learning process involves mat r students activities. (3) Chemical reactions are consistently presented in all three types of representation. 

Arrow pushing is much like riding a bike. If you have never done it before, watching someone else will not make you an expert. You have to leam how to balance yourself. Watching someone else is a good start, but you have to get on the bike if you want to leam. You will probably fall a few times, but that s part of the learning process. The same is trae with arrow pushing. The only way to leam is with practice. 

The only way to traly master problem-solving is to practice problems every day, consistently. You will never learn how to solve problems by just reading a book. You must try, and fail, and try again. You must learn from your mistakes. You must get frustrated when you can t solve a problem. That s the learning process. Whenever you encounter an exercise in this book, pick up a pencil and work on it. Don t skip over the problems They are designed to foster skills necessary for problem-solving. 

In the bottom-up approach the initiative to start the learning process is taken by one of the infimal decision units. Since solutions found at this unit may include connection variables, the request for given values of these variables is propagated backward, to unit A + 1, through temporary loss functions. After successive backpropagation steps, the participation of several other fhe operators associated with them, a final decision... 

On the other hand, the top-down approach starts the learning process at the supremal decision unit, DUq, and only on a second stage does it move down to the infimal decision units for approval and validation. 

In the top-down approach the supremal decision unit, DUq, starts the learning process by itself, and identifies a decision policy, X p. Then, in a... 

The learning process was initiated at the top-digester infimal decision unit, leading to a solution, Xjj, that involves local decision variables and a range of white liquor sulfidity (fraction of active reactants in the white... 

The learning process with respect to the problem of the origin of life took place in a manner similar to the three stages described by the French philosopher Auguste Comte (1798-1857) for the linear history of progress in human culture. These three stages are ... 

The networks can adapt themselves to produce a desired output. This adaptation is usually achieved by changing the synaptic weights, and this process is defined as learning. Some networks carry out the learning process by relying on task examples. 

NN applications, perhaps more important, is process control. Processes that are poorly understood or ill defined can hardly be simulated by empirical methods. The problem of particular importance for this review is the use of NN in chemical engineering to model nonlinear steady-state solvent extraction processes in extraction columns [112] or in batteries of counter-current mixer-settlers [113]. It has been shown on the example of zirconium/ hafnium separation that the knowledge acquired by the network in the learning process may be used for accurate prediction of the response of dependent process variables to a change of the independent variables in the extraction plant. If implemented in the real process, the NN would alert the operator to deviations from the nominal values and would predict the expected value if no corrective action was taken. As a processing time of a trained NN is short, less than a second, the NN can be used as a real-time sensor [113]. 

In mice, exposure to DDT during gestation and in the neonatal stage has also caused developmental neurotoxicity, in the form of behavioral deficits in the learning process, that persisted into adulthood. Human studies have suggested that alterations in functions that are hormonally controlled such as duration of lactation, maintenance of pregnancy, and fertility may occur from DDT exposure. ... 

To further assist the learning process, readers may find it useful to consult other textbooks or literature references. Several particular texts are recommended for additional reading, further details, or simply an alternative point of view. They include the following (in each case, the abbreviated name used in this text is given following the proper reference) ... 

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