The incremental plan in practice is not allowed. It is strictly forbidden to reprint this column This paper is reproduced from the software engineering expert network www.21cmm.com. Do not reprint without CBS, thank you for the new increment of the system Careful design, overall goals, and constraints on the basis of incrementally achieved functions will gradually grow into a system. That is to say, a new function in an increment will insert an early increment of a predefined structure, and should meet a child specification consistent. This function allocation process is a practical application that references transparency in an incremental development plan. Therefore, logical allocation of the incremental function is based on the inter-functional relationship, which is the definition of incremental content from the attribute. For example, in a database system, adding data is usually prior to deleting a function of data. In the statistical system, the functions that mourn and input are usually the function of analytical data and report results. In a functional dependent system framework project, large-scale management and technical factors affect the increment plan. User needs users want some system functions to operate before the system is complete, which is generally arranged in an early increment plan. The common motivation behind the need for iterative development methods is based on this fact: the demand is rarely established in the beginning of the project. Using incremental development, users provide feedback to the executable increment, and relatively clear demand affects the increment plan in two ways. Easy demand is achieved in early increments, so it is easy to clarify. Alternatively, when the problem affecting the demand is determined, the unstable demand may plan to be reached later. For example, if the user interface is not well established, this method is an ideal choice for early increment (someone will say that the user interface is always the most variable in the system, and should be implemented in an early increment). On the other hand, the demand determined by consistent research may be arranged in later increments. Operation User Probability Function The distribution is part of the top-level clean room software specification. The probability of using system features is established by historical data and user estimation. The system feature that is expected to use probability is universally used in the system, so it is beneficial to test. Since the increment is gradually accumulated, the function is designed in an early increment, and when the new increment enters the test process, each time you need to test. Therefore, it is expected that the system functionality of the user's frequent use should be scheduled to be in an early increment, and some of the low usage can be considered optional. If time allows, it should be scheduled to be implemented in the final increment. Reliability management is gradually, the rooms are concerned about formal software reliability requirements. Poore, Mills and Mutchler (1993) describe the ways of incremental plan based on high-level designed subsystem reliability requirements. Given a renovation system reliability and transition probability between subsystems, the reliability requirements of each subsystem will be calculated. The highly reliable demand subsystem has a great impact on the reliability of the entire system and should be planned in early increments. System engineering control iteration is a key engineering theory in hardware design. Minimum machines are typically constructed in the earliest iteration, then repeat iteration until the full machine is manufactured, the software incremental development is completely like standard hardware design. Embedded software The machine must work coordinate between hardware engineers and software engineers, incremental development is the ideal architecture of this coordination. For example, the machine must energize before use. Therefore, the system startup software should be implemented in the early incremental function of the embedded software item. Technical challenges of novel or especially complex components may be a kind of adventure, even an adventure for the capacity of the project. If this work is arranged in an early increment, this practice will support existing plans or recommendations to modify the plan. If the project itself is novel, the complexity is reflected in the panel's practice, then the work and progress flexibility of the team should be evaluated as soon as possible. The effects of reuse and the function of the net chamber have emphasized that their economics is reflected in the reuse of components in the project, and the "common service" components that can be used in the system.
