Humans in Work System Environment - Fundamentals and Assessment Tools for Occupational Ergonomics - page 78

takes up, for example, an advisory service. The substantial output of the work system can be, in this
case, immaterial and exist in additional knowledge, which the customer can acquire by the usage of
the advisory service.

5.3.2.4 Working Equipment and Operating Resources
A meaningful classification of technical systems, which are also called working equipment and operating
resources can be considered in accordance with Figure 5.7 on the basis of the system function and the
system output (Ropohl, 1979).
The categories “transformation,” “transport,” and “storage” can be differentiated regarding the system
function. Transformation means that the outputs of a system are quantitatively and

or qualitatively
different from the system inputs. Transport signifies that only the spatial and temporal coordinates
between inputs and outputs change while the material, energetic, and informational attributes remain
constant in quality and quantity. The function class “storage” is concerned; if only the temporal coordinates
of the output differ from those of the input while all other attributes (material, energy, information, space)
are not subject to change. These function classes can be assigned to the following three terms: production
technique, transport technique, and storage technique. The term of production is to be understood in close
technical sense.
The output of a technical system can be differentiated regarding material, energy, and information.
Material is everything that possesses mass and takes up physical space. Energy is defined as the ability
to carry out work in a physical sense. By information, a configuration or a series of symbols is understood
to which a certain meaning can be attached and which can lead to certain behavior.
Single technical subjects can be assigned to the individual fields of the pattern represented in
Figure 5.7. Thus, for example, the process engineering and the manufacturing technique are located
in the field of “material

/

transformation.” While process-engineering systems produce materials with
exactly defined chemical and physical characteristics, the output of manufacturing systems consists of
products with exactly defined material and geometrical characteristics. Complex technical systems,
which contain many subsystems in relation with each other can be assigned to a field regarding their

/

FUNCTION
CATEGORY

TRANSFORMATION TRANSPORT STORAGE

OUTPUT

production technique transport technique storage technique

process engineering materials handling

and conveying

warehouse engineering

manufacturing
technique

energy storage
technique

energy transformation
technique

energy transmission
technique

information processing
technique
metrology
control and feedback
control technique

information transfer
technique

information memory
technique

FIGURE 5.7 Classification of technical systems (in modification of Ropohl, G., Eine Systemtheorie der Technik — zur
Grundlegung der allgemeinen Technologie. Hanser, M¨nchen, 1979. With Permission).