Humans in Work System Environment - Fundamentals and Assessment Tools for Occupational Ergonomics - page 64

5.1 Objectives and Structure of the Article
System theories are closely connected to the development of individual branches of science. Thus, system-
theoretical approaches can be found in numerous scientific fields like biology, ecology, pedagogy, business
administration, organization theory, engineering science, and political science. System-theoretical realiz-
ations are integrated into the own scientific field — with the concept of the work system.
The starting point of various system-theoretical developments was formed by the system-theoretical-
cybernetic approach. This mathematical approach contributed, considerably, to the fact that the system
idea is applied to a set of scientific subjects. Individual scientific fields, in turn, provided impulses for the
advancement of system theories. Due to various system-theoretical realizations an overview of system
theories and approaches — how it is given in the first part of this article — can, inevitably, be only
one interpretation of the manifold literature. The depiction of individual system-theoretical approaches
in the first part of this article orients itself primarily towards several branches of science. Thus, the
socio-technical system approach originating from social psychology is introduced as it corresponds
with its own conception of a work system. The theory of social systems — originating from
sociology — provides several impulses for other scientific fields. As a result, the individual develop-
ment stages of the theory of social systems are outlined. This theory and other branches of science
like business administration in turn took up realizations from the evolution theory. For this reason,
this theory — originating from biology — will also be explained. Furthermore, this part exemplifies
how system-theoretical realizations were integrated into engineering science. The single system-theoretical
approaches are constituted in conjunction with the appropriate idea of man in each case. This should help
when comparing the individual approaches with the own normative requirement of designing work in a
human and economic way.
In another part of the article the work system concept is described in detail as an entry to the systema-
tic analysis, common in ergonomic literature. This part deals with the term “work system,” the com-
ponents of a typical work system, and its substantial reciprocal effects.
The last part of the article is dedicated to the systematic design of work systems. First of all general
strategies of work system design are explained. Subsequently, models and methods are presented, exem-
plarily, based on a level scheme for the systematical order of work-referred realizations. These models and
methods are able to support a systematical proceeding with the anticipating and prospective work system
design. These approaches and methods are the result of research projects, which were accomplished by
the Institute of Industrial Engineering and Ergonomics (IAW) and by the Research Institute for Oper-
ations Management (FIR) at the RWTH Aachen. The exemplarily cited research results are supposed
to show that the use of the work system approach is possible and reasonable on different levels of ergo-
nomic research.
5.2 Overview of Selected System Approaches
5.2.1 General System Theory and Cybernetics
Ludwig von Bertalanffy (1949) is considered as an important founder of the “General System Theory.” He
defines systems as whole units, which consist of interconnected parts. He explains the proportion of
whole units to their parts with the help of a holistic axiom. Referring to this, the characteristics and beha-
viors of higher levels are not explainable by the summation of the characteristics and behaviors of their
components, as long as these are regarded in isolation. Only if the ensemble of the components and the
relations, which exist between them are realized — so the axiom — the higher levels are derivable from
their components. The whole — so the central theorem — is more than the sum of its parts.
During the investigation of the development of individual fields of science, Ludwig von Bertalanffy
(1951) discovered “the remarkable phenomenon that similar general problems and viewpoints appear
in the different branches of science.” Among others, he cites the exponential law as an example. This
law “applies to radioactive decay, to the breakdown of a chemical compound in monomolecular reaction,