Spec/ refinement operator

Operation refinement, then, means to write code that conforms to an effects spec, which can be tested by writing the spec in executable form. Operational is the form of abstraction having the longest history, dating back to Turing. Those who crave mathematical certainty that their code conforms to the spec are referred to [Morgan] or [Hoare]. 

When we design a procedure that refines an operation spec, we can focus on the receiving object and devolve subtasks to other objects we send messages to. If we change the design, we are changing this one object. 

Refining an operation is like designing a computer monitor You have the specs of the signals that come along the wires and their required manifestations on the screen. Your work is to define the insides of the box you may involve others by specifying parts you will use inside. Your design talks about the specifications of the constituent parts and how they are wired together. 

Type model plus system specs The system context is defined, and the primary actions that the system participates in are first specified as abstract actions, and then refined to a level of an approximately atomic interaction with the system. Atomic interactions are those that, unless completed, would not constitute meaningful or useful operations on the system. 

Components in Catalysis need not be built using object technology. The concept of a type model and operation spec can be applied equally to a Java, C++, COBOL, or assembler implementations—and therefore to legacy systems—thanks to refinement. 

Water can cause severe operational problems in services which are not meant to handle it. One refiner (296) stated that 99 percent of his fractionator upsets are due to water other refiners (296) agreed with this evaluation. Most problems occur when the column separates water-insoluble materials such as hydrocarbons. The main adverse effects of water in such services are pressure surges, flooding, cycling, corrosion, hydrates, and off-spec products. Typical sources of water in this t5q>e of services are... 

In September 1963, the USAF released MIL-S-38130. This specification broadened the scope of the system safety effort to include aeronautical, missile, space, and electronic systems. This increase of applicable systems and the concept s growth to a formal Mil-Spec were important elements in the growth of system safety during this phase of evolution. Additionally, MIL-S-38130 refined the definitions of hazard analysis. These refinements included system safety analyses system integration safety analyses, system failure mode analyses, and operational safety analyses. These analyses resulted in the same classification of hazards, but the procuring activity was given specific direction to address catastrophic and critical hazards. 

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