Realization phase software

During the concept and realization phase, requirements are derived from the collected use-cases and business as well as administration services are formulated. A functional architecture of the SE environment is to be defined, in which supporting services are considered. The methods of the different disciplines involved are to be aligned in order to take a higher benefit of SE. Thus, the concept considers not only the necessary software, but also the methodological way of working. 

Figure 11 - Application software safety life cycle (in realization phase)...

Software specification (Clause 7.2) As seen from the previous table, the first part in realization phase of software starts with the requirements of software specification. Specification, including terminologies, shall be clear, precise, verifiable, testable, maintainable, and feasible, and detailed enough to allow... 

Software safety life cycle in process industries. (A) Software in realization phase (B) safety life cycle relation between software and safety instrumented system. 

The first objective of this sub-phase is to develop a software architectural design that realizes the software safety requirements... 

Note the stages of the lEC model. The first 4 phases are concerned with design, then the realization phase is reached. This term describes in very general terms the job of actually building the safety system and implementing any software that it contains. 

Large sections of lEC 61508 are concerned with the details of the realization phase and there are whole life cycle models for the activities contained within this stage. Some sections of the lEC standard are dedicated to these specialized tasks. Bear in mind that some of the deeper parts of this standard will be applicable to manufacturers of certified safety PLCs and their associated software packages. A process engineering project would not be expected to dive into such depths. 

The H-NMR spectra of FCC feeds were recorded on a Bruker DRX 400 MHz NMR spectrometer. The concentration of the samples of 5 wt% in CDCI3 was recommended by Molina, Navarro Uribe, and Murgich [2] to avoid concentration dependence of the chemical shift. A 30° pulse sequence was applied, with 4.089 s acquisition time, 2 s pulse delay [2], 8012.8 Hz spectral width, and 64 scans. Hexamethyldisiloxane (HMDSO) was used as a reference. NMR processing was realized using MestReNova software. The phase and baseline of the resulting spectra were manually adjusted and corrected. The spectra were integrated six times and average values were taken for the purpose of calculations. The spectra were divided... 

The required SIL designates the methods and measures that have to be executed during the overall safety lifecycle phases. The SIL is a probabilistic quantitative concept. If certain techniques and measures are applied one expects on average that a certain reliability of the safety functions is realized. Besides statistic and systematic hardware errors this concept also takes systematic software failures into account. 

Realization (requirements) phase for E/E/PEs safety related software Yes Yes ... 

Similar schemes [7, 11] exist for the Eq. (3). However, ealeulations of phase transitions using Eq. (3) always need regularization and a small time step. Because of a quasilinear character of Eq. (3) systems of linear equations appear when using implicit schemes. This allows to build an implicit scheme called a double-sweep method of variable directions. Consumption of machine time for realization of one time step here is of the same orders that in the explicit schemes. However, the inclusion of the additional calculated objects, which should be provided with the boundary conditions in this scheme, makes the algorithm much more complicated. For this reason explicit schemes are used in the software. 

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