Process (engineering)
Encyclopedia
In engineering
a process is a set of interrelated tasks that, together, transform inputs into outputs. These tasks may be carried out by people, nature, or machines using resources; so an engineering process must be considered in the context of the agents carrying out the tasks, and the resource attributes involved. Systems Engineering
normative documents and those related to Maturity Models are typically based on processes. For example, System Engineering processes of the EIA-632 and processes involved in the Capability Maturity Model Integration
(CMMI) institutionalization and improvement approach. Constraints imposed on the tasks and resources required to implement them are essential for executing the tasks mentioned.
s used to produce a material in large quantities.
In the chemical industry, chemical engineers
will use the following to define or illustrate a process:
The CPRET representation integrates the process Mission and Environment in order to offer an external standpoint. Several models may correspond to a single definition depending on the language used (UML or another language).
Note: process definition and modelling are interdependent notions but different the one from the other.
This definition requires a process description to include the Constraints, Products, Resources, input Elements and Transformations. This leads to the CPRET acronym to be used as name and mnemonic
for this definition.
>
Examples of processes
Examples of environment
Examples of mission
Examples of constraints
Examples of products
Examples of resources
Examples of elements as inputs
Examples of transformations
This definition states that environment is an external factor which cannot be avoided: as a matter of fact, a process is always interdependent with other phenomena including other processes.
Engineering
Engineering is the discipline, art, skill and profession of acquiring and applying scientific, mathematical, economic, social, and practical knowledge, in order to design and build structures, machines, devices, systems, materials and processes that safely realize improvements to the lives of...
a process is a set of interrelated tasks that, together, transform inputs into outputs. These tasks may be carried out by people, nature, or machines using resources; so an engineering process must be considered in the context of the agents carrying out the tasks, and the resource attributes involved. Systems Engineering
Systems engineering
Systems engineering is an interdisciplinary field of engineering that focuses on how complex engineering projects should be designed and managed over the life cycle of the project. Issues such as logistics, the coordination of different teams, and automatic control of machinery become more...
normative documents and those related to Maturity Models are typically based on processes. For example, System Engineering processes of the EIA-632 and processes involved in the Capability Maturity Model Integration
Capability Maturity Model Integration
Capability Maturity Model Integration is a process improvement approach whose goal is to help organizations improve their performance. CMMI can be used to guide process improvement across a project, a division, or an entire organization...
(CMMI) institutionalization and improvement approach. Constraints imposed on the tasks and resources required to implement them are essential for executing the tasks mentioned.
Semiconductor Industry
Semiconductor process engineers face a unique challenge: to transform raw materials into high-tech devices. Typical semiconductor devices include Integrated Circuits (ICs), Light-Emitting Diodes (LEDs), solar panels, and solid-state lasers. To produce these and other semiconductor devices, semiconductor process engineers rely heavily on interconnected physical and chemical processes. One such example is ultra-violet photolithography followed by wet etching, whereby an IC pattern is transferred onto an organic coating and etched onto the underlying semiconductor chip. Other examples include the ion implantation of dopant species to tailor the electrical properties of a semiconductor chip, and the electrochemical deposition of metallic interconnects (electroplating). Process Engineers may participate in the development of new semiconductor processes, scale-up of these processes from lab bench to manufacturing floor, and quality control on the manufacturing floor.Chemical engineering
A chemical process is a series of unit operationUnit operation
In chemical engineering and related fields, a unit operation is a basic step in a process.Unit operation involves bringing a physical change such as separation, crystallization, evaporation, filtration etc.. For example in milk processing, homogenization, pasteurization, chilling, and packaging are...
s used to produce a material in large quantities.
In the chemical industry, chemical engineers
Chemical engineering
Chemical engineering is the branch of engineering that deals with physical science , and life sciences with mathematics and economics, to the process of converting raw materials or chemicals into more useful or valuable forms...
will use the following to define or illustrate a process:
- Process Flow DiagramProcess Flow diagramA process flow diagram is a diagram commonly used in engineering to indicate the general flow of plant processes and equipment.The PFD displays the relationship between major equipment of a plant facility and does not show minor details such as piping details and designations...
(PFD) - Piping and instrumentation diagramPiping and instrumentation diagramA piping and instrumentation diagram/drawing is a diagram in the process industry which shows the piping of the process flow together with the installed equipment and instrumentation.-Contents and Function:...
(P&ID) - Simplified process description
- Detailed process description
- Project management
- Process simulationProcess simulationProcess simulation is used for the design, development, analysis, and optimization of technical processes and is mainly applied to chemical plants and chemical processes, but also to power stations, and similar technical facilities.- Main principle :...
CPRET
The Association Française d'Ingénierie Système has developed a process definition dedicated to Systems engineering (SE), but open to all domains.The CPRET representation integrates the process Mission and Environment in order to offer an external standpoint. Several models may correspond to a single definition depending on the language used (UML or another language).
Note: process definition and modelling are interdependent notions but different the one from the other.
- Process
- A process is a set of transformations of input elements into products: respecting constraints,
- requiring resources,
- meeting a defined mission, corresponding to a specific purpose adapted to a given environment.
- Environment
- Natural conditions and external factors impacting a process.
- Mission
- Purpose of the process tailored to a given environment.
This definition requires a process description to include the Constraints, Products, Resources, input Elements and Transformations. This leads to the CPRET acronym to be used as name and mnemonic
Mnemonic
A mnemonic , or mnemonic device, is any learning technique that aids memory. To improve long term memory, mnemonic systems are used to make memorization easier. Commonly encountered mnemonics are often verbal, such as a very short poem or a special word used to help a person remember something,...
for this definition.
- Constraints
- Imposed conditions, rules or regulations.
- Products
- All what is generated by transformations. The products can be of the desired or not desired type (e.g., the software system and bugs, the defined products and waste).
- Resources
- Human resources, energy, time and other means required to carry out the transformations.
- Elements as inputs
- Elements submitted to transformations for producing the products.
- Transformations
- Operations organized according to a logic aimed at optimizing the attainment of specific products from the input elements, with the allocated resources and on compliance with the imposed constraints.
CPRET through examples
The purpose of the following examples is to illustrate the definitions with concrete cases. These examples come from the Engineering field but also from other fields to show that the CPRET definition of processes is not limited to the System Engineering context. <Examples of processes
- An engineering (EIA-632, ISO 15288ISO 15288The ISO/IEC 15288 is a Systems Engineering standard covering processes and life cycle stages. Initial planning for the ISO/IEC 15288:2002 standard started in 1994 when the need for a common Systems Engineering process framework was recognised. The first edition was issued on the 1st of November...
, etc.) - A concert
- A polling campaign
- A certification
Examples of environment
- Various levels of maturity, technicality, equipment
- An audience
- A political system
- Practices
Examples of mission
- Supply better quality products
- Satisfy the public, critics
- Have candidates elected
- Obtain the desired approval
Examples of constraints
- Imposed technologies
- Correct acoustics
- Speaking times
- A reference model (ISO, CMMI, etc.)
Examples of products
- A mobile telephone network
- A show
- Vote results
- A quality label
Examples of resources
- Development teams
- An orchestra and its instruments
- An organization
- An assessment team
Examples of elements as inputs
- Specifications
- Scores
- Candidates
- A company and its practices
Examples of transformations
- Define an architecture
- Play the scores
- Make people vote for a candidate
- Audit the organization
Conclusions
The CPRET formalized definition systematically addresses the input Elements, Transformations and Products but also the other essential components of a Process, namely the Constraints and Resources. Among the resources, note the specificity of the Resource-Time component which passes inexorably and irreversibly, with problems of synchronization and sequencing.This definition states that environment is an external factor which cannot be avoided: as a matter of fact, a process is always interdependent with other phenomena including other processes.