Inter-Process Communication

IPC Inter Process Communication, unbuffered and synchronous. Utilises blocking and timeout facilities. Short messages of 8-bytes can be implemented using registers alone. 

This section describes methods for representing processes and inter-process communication mechanisms in ISPS and the Workbench, and two methods that could be used for implementing those processes and their communication in hardware. A transformation for creating these processes is described in the next section, along with its effect on the VT and on the final design. 

In the field of computer science, processes, concurrency, and interprocess communication are well understood [Dijkstra68, Hoare78, Andrews83]. The execution of a set of sequential statements is called a process, and the parallel execution of two or more processes is referred to as concurrent execution. The transfer of data between two processes is called inter-process communication, and insuring that inter-process communication takes place at a mutually-agreed-upon time is called synchronization. 

The crucial problem of conversation placement has received somewhat less attention. In effect the designer must identify the extent of process corruption and error migration through inter-process communication for all faults in the system. The objective of this fault effect analysis is the identification of a boundary or set of properly nested boundaries, which define known entry (recovery line) and exit (acceptance) states for the system. This allows the entry and exit state for each component process to be determined. Software must be designed to save recovery line entry states, and to implement and synchronise the acceptance tests on all processes in the conversation. Attempts to identify recovery lines and acceptance points dynamically are prone to progressive collapse (20). 

Increasingly fruitful, as common concern in meeting society s legimitate needs for practical detection capabilities bind us together, and as we each invest our efforts in our respective areas of expertise. Mutual education and inter-cultural communication can only accelerate this process. 

Maturity levels of information system are presented in Fig. 22.4. At the first level a product data management (PDM) system needs to be introduced. A PDM/PLM system is a meeting point for project team members where all project-related documents are available. At the second level an advanced level of visualisations tools is requested. Clear presentation of components and assemblies with 3D models and viewers is necessary for inter-team communication, especially in a spatially distributed environment. At the advanced level of PLM implementation PDP specific workflows are available for change management and for milestones approval. This level also involves external team members. At the top level the PDP is integrated with other business processes. 

The expected time to execute home appliances development projects in man-year is longer than for modules or elements. Bigger core teams should be collocated in the same office to enable smooth inter-team communication. Some of the activities for vacuum cleaner motor development, which were managed before by external team members located in functional departments, are now managed by core team members. For example, industrial designers inside a core team communicate directly with end users, a specialist for process planning has direct contact with tool suppliers. Direct communication reduces the probability of wrong data interpretation and improves the transfer of information inside the core team. It is known that increased physical distance between employees workplaces dramatically reduce the frequency of informal communication and data transfer [2]. 

Quality consists of two elements quality of conformance (have we met specifications ) and quality of design (are the specifications correct ). In the case of the behaviour-based approach, such specifications are expressed in terms of specific, observable and measurablebehaviours.Ratherthan being a somewhat abstract truism, quality is, in effect, defined for sub-units of the overall process in terms of specific units of behaviour. The previous use of this approach for safety improvement suggests that it would work equally well for quality of conformance. Quality of design, however, is dependent on increasing levels of inter-departmental communication and the establishment of an internal quality model. Therefore, the approach should facilitate both a team model and an internal customer approach to quality improvement. Before this structure is discussed in detail, it is important to consider the issue of gaining commitment to a quality improvement process. 

These message groups can be constructed using any of the above communication primitives. However, detailed study is required to ensure that the logical structure of the inter-process action (the transaction level) is not disrupted should the lower level communication primitives fail in a particular application (14). Single failure detection systems, such as time-outs, can only be applied at process level on a per-process basis and this does not necessarily provide protection at the... 

Inter-partition communication is performed through the ARINC-653 transport mechanism. This transport is based on the definition of sampling and/or queuing ports which are statically connected by means of communication channels. All these communication entities are entirely defined through a configuration file, and the same configuration scheme can be used for ports allocated to the same or a different node. Therefore, this process decouples applications from system and partition configuration. 

Demand in the lead market, however, is sophisticated enough to already take pairt in the development process and can give feedback for improving and refining a product. Traditionally, test markets are often selected because of their isolated situations in order to avoid interference with non-resident customers. Hong Kong and formerly Western Berlin are such ideal test markets. Isolation, however, supports idiosyncratic demand. Dense inter-regional communication, which facilitates worldwide diffusion of innovations and the influx of outside market information, is one of the features of the lead market. The traditional criteria of test market selection should therefore not be applied to lead markets. On the contrary, a lead market concept can be a powerful method to select test markets. 

The importance of consensus in terminology was highlighted by a misunderstanding of the analytical procedures employed, because of a differential use of the labels, primary, secondary and circumpulpal dentine, by different research groups. This indicated one area where improvements in inter-study communication could be made with ease. Exchange of personnel between study groups to observe analytical procedures, or a video-recording to demonstrate the process, would resolve such differences. The latter procedure would also provide a record which could be kept for reference purposes. 

---