Notes on Introduction to computing science (1)

 

The book name is actually an excerpt from some of the useful words in the book. Introduction to computing science is a book written by Dr. Zhao zhizhuo of Xiamen University to students majoring in computer science. After my graduate students, I have been thinking about the connotation of computer science and the path I should choose. After reading this book, I have a deep understanding of the history, status quo, and connotation of computer science. On the basis of a clear understanding of computer science, my sense of direction has also increased. In particular, this book emphasizes the computer theory and mathematical basics that are easy to be ignored by computer learners. The connotation of computer science is mathematics, and computer science is as elegant and colorful as mathematics. When I graduated from high school, I had nothing to know about computers and thought that computers were very fun. After four years of study, I felt that computers were very boring and very clever. After I went deep into computer science, I deeply realized what is "the beauty of the palace room, the wealth of hundreds of officials ". Computer science is really great. This discipline is based on rigorous mathematics and quickly becomes a magnificent building, it will become the third perfect scientific system for mankind after mathematics and physics. Moreover, computer science, with "computing" as its soul, will surely survive forever, because the thoughts, methods, and content of this subject do not depend on the specific technical environment.

1) Disadvantages of Computer Science Education: "... Teachers and students put too much teaching energy into simple computer practice, and tend to expand the development of knowledge, ignoring the objective requirements of the subject that should have taken the path of connotation development for classroom teaching and experimental teaching, we have relaxed the learning of basic theoretical knowledge ..."

2) experience tells us that it is even more difficult to learn computer science than to study basic mathematics, because many of its theoretical courses are not as simple as Mathematics Courses in depth, and at the same time, students must learn a lot of practical content, the knowledge update cycle is short. Combining theory with practice, the unification of theory and practice is a major feature of computer science, which determinesDuring learning, students must constantly switch their learning methods between rigorous logical thinking and image experiment operations.This is not easy for most people. Moreover, the development of computing science is extremely fast, and the task of supplementing and updating the knowledge organizational structure in the work is overwhelming, making people breathless.

3) when it comes to computing models and mathematics, there is always a need to involve the concept of formal methods.FormIs the sum of the external methods, shapes, and structures of the content of a thing. The so-calledFormalizationIt is to separate the content and form of a thing and express it in a certain form of thing.Formal MethodIt is the general term for the whole method of describing the laws of changes of things by studying the laws of the forms of things.

4) The Turing machine has proved to have a strong computing capability. It was developedRecursive Function Theory(A theory capable of computing) One of the most common computeable functions (some recursive functions or some computeable functions) is equivalent in terms of computing expression ability.

5) according to the Turing Machine and computing theory, in fact,An abstract computer requires only a few basic computing commands to have powerful computing capabilities.. What technology is used to express this computing capability depends entirely on the development level of industrial technology in the society at that time... Stored program computers can be manufactured by mechanical or electronic technology, and may even be manufactured by other new technologies in the future .... A computing process can be implemented either by a program or by a circuit. That is to say, electronic technology and program technology are only two basic forms of computing science.
The core content that truly constitutes the basic computing science is a large amount of regular knowledge around computing, rather than a specific implementation technology.

6) in computational science research, there is actually a rule: a problem, when it can be described as a solution or a processConstructive Mathematical DescriptionIn addition, if the universe involved in this problem is poor, or if it is infinite but there is a poor representation, the problem must be solved by a computer. In turn, any problem that can be solved by a computer, the process of solving the problem must be mathematical, and the mathematical process is constructive.

7) the parity principle tells us that in the parallel computing model, the computing time and space can be exchanged. If an algorithm reduces the complexity of computing time, it can often be replaced by sacrificing space complexity, and vice versa. (Why? Is there a theoretical basis ?)