Industrial gases HS code verification

List of the table of contents of this article:

• 1,Industrial gases HS code verification What is system analysis and system design?
• 2, Catalog of Software System Analysis and Design
• 3, Key points of systematic structured analysis and design
• 4, What is the difference between system analysis and system design

What is system analysis and system design?

1. System analysis is to decompose the user's ideas through task decomposition, and analyze the user's relatively general needs into needs that can be understood by research and development. System analysts are closer to users than system designers, mainly demand analysis and business analysis. System design is based on the needs of users, and the system needs to be designed to meet the needs of the analysis.

2. In general, system analysis and system design are two different but closely related stages in software engineering. System analysis is mainly to understand and describe user needs and problems and provide a basis for system design; while system design is to solve these needs and problems and design a system that meets the needs.

3. System analysis is regarded as an important procedure and core component of system engineering, as well as an application of system theory. In the life cycle of system development, the system analysis stage predes the system design, which is an indispensable work in the early stage of system development.

4. The method of systematic analysis has been widely applied. System design is the physical design stage of a new system. According to the logical model and functional requirements of the new system determined by the system analysis stageUnder the environmental conditions provided by the user, design a scheme that can be implemented in the computer network environment, that is, establish a physical model of a new system.

5. The content determined by system analysis is the basis for future system design and system realization. Elements: (1) Information. Completely describe all the information processed in the system; (2) Behavior. Fully describe the processing or function (3) representation required for system state changes. Describe the external interface and interface of the system in detail.

6. System analysis is also known as "system method". With the overall optimality of the system as the goal, qualitative and quantitative analysis of all aspects of the system is carried out.

Catalogue of Software System Analysis and Design

Understanding the basis of the operating systemThis concept, main function, main component, master the design method and implementation technology of each component of the operating system. Be able to use the operating system principles, methods and technologies learned to analyze and solve relevant problems.

Software architecture focuses on the global organizational form of the software system, grasps the intrinsic connection between the parts of the system at a higher level, and shifts the focus of software development from hundreds of codes to the design of larger-grained architecture elements and their interactions.

User view is the page style that software users (including end users and management users) can see, which contains many operational processes and conditions. The data dictionary refers to the logical relationship of the data and sorts it out. After completing the data dictionary, more than half of the design of the database is completed.

The JSD method is actually a set of continuous technical steps that support software analysis and design: (1) Entity action analysis: from the description of the problem, extract the entity (people, objects or organizations) to be generated and used by the software system, as well as the actions (events) that the real world acts on the entity.

Key points of systematic structured analysis and design

The basic points of structured programming methods are: (1) Adopt a top-down and step-by-step program design method. In requirements analysis and outline design, the top-down and layer-by-layer refinement method is adopted.

The overall structure design of the system is to roughly design the overall structural form and available resources of the new system according to the requirements of system analysis and the actual situation of the organization, which is a kind of macro and overall design and planning.

The basic points of the constructive programming method are as follows: any complex algorithm can consist of three basic structures: sequential structure, selective (branch) structure and circular structure.

I think the code obtained in the end according to these two analysis and design methods should be so similar that it is difficult to see the style of system analysis.

What is the difference between system analysis and system design

System analysis and system design are two important stages in the development process of information system, which have different goals and contents: system analysis: system analysis It is the first stage of information system development. Its main goal is to comprehensively and deeply understand user needs and problems, and to determine system solutions to solve problems.

System designers are closer to technology than system analysts. They are technical experts and senior technicians. Contact system analysis and system design are both advanced abstraction levels. As a senior software title qualification, it is a leader and technical consultant for programmers and software designers.

Users of mobile applications needThe difference between definition and traditional system analysis is that the system requirements are different, the focus and the angle are different. Different system requirements details User requirements definition: There is no clear and meaningless system requirements in the definition of user requirements.

Analysts prefer demand analysis, while architects mainly do system architecture design and technology. Analysts usually also need strong technical ability to work in small and medium-sized systems, and analysts can replace the work of architects. On the other hand, if it is not a highly professional field, architects can also do the work of analysts.