Abstract:

Digital Number (DN) is an important technical term for data collection used in information science. It is important to identify the relationship between DN and all the aspects in the relevant areas and to resolve current problems of how to use DN in the remote sensing technology, mathematics, and computer science. This provides a good solution to improve the quality of the documents. This paper presents a guideline how to use DN. The definition of DN is reviewed and how DN is used in data collection and also DN’s evolution is present. The relationships between DN and analog quantity, DN and numerical number, and the boundary between DN and non-DN are defined. The digital structure, digital marking and how DN should be used in related levels in the system are stated. Ten items are formed for analysis and comparison when DN is used. The currently DN usage has issues in five areas: DN’s definition, usage in different technical areas, expression of the numerical numbers, mathematical expression, and awareness of digital marking. The issues are discussed and then solutions are presented to overcome the issues. The DN is clearly defined. Contributions of the paper: define the relationship between DN and analog quantity; summarize the problems of miss usage of DN and the errors may be produced; redefine the numerical number including the DN sources, the numerical number structure and format including all DN branches; better define the parameters used in DN, numerical numbers, non-numerical numbers; standardize the usage of terms in digital technical area and mathematics. The results show that to improve the understanding of DN and better mathematic explanation; and help eliminate various expression problems of DN in remote sensing technology, mathematics, and computer science.

Key words: digital coding, DN, expression, analog value, numerical number, numerical number type