In the previous chapter, we saw that nonlinear dynamical systems (NLDS) are subject to complex behaviors. They are “programmable networks” whose functions and interactions are not necessarily linear. We encounter them in all fields: industrial, financial, economic, social, political, etc.
When we have qualitative systems, it is relatively easy to build a mathematical model of the phenomenon or system evolution, to evaluate it and study its behavior. When we have quantitative information, the development of the model is much more difficult; so is the study of the model.
In a manufacturing system dedicated to the assembly and testing of complex technological sets, the problem is what will determine the quality of the product and the performance of the manufacturing process: “will it remain stable? Will productivity be optimal? Does the production system remain under control?” So many questions that a production manager asks himself or herself.
First, it should be noted that in a conventional system, most tasks are often performed directly. These same tasks to be performed are under the control of a human being and several elements must be taken into account to characterize the level and nature of an organization in which human resources are involved, namely:
The functioning and behavior of such an organization depends of course on these three elements and their combination. The French mathematician René Thom examined this problem through his theory of “catastrophes”, which allowed him to highlight transition phenomena and discontinuities, of which we will mention only two examples:
As we have just seen, the effectiveness and efficiency of an organization carries with it the skills, culture and motivation of the system. A good distribution between these skills and good coordination between the different entities is based on a system of links with the four main characteristics.
This is synonymous with responsiveness and adaptability. Processes must be able to be linked and interact with each other as quickly as possible. The definition of needs and their characteristics must be rapid and lead to the immediate design and development of the required products and services. Current IT tools combined with customer relationship management (CRM), technology monitoring, computerized and integrated modeling and design techniques make it possible to meet this demand. This is currently the case in the automotive industry, electronics, high technologies, etc. Large companies such as Dell, IBM, Peugeot, Renault or even the Airbus EEIG consortium, etc. are structured in this way and can ensure a rapid introduction of new products to the market.
Computer technologies and the Internet have brought about two major advantages:
These properties are those that we classify under the headings “lean” and “agile manufacturing”.
This criterion is also the credibility of the system in which we operate. Parameters such as quality, reliability, performance, availability or even serviceability help to achieve this. However, according to an IBM internal quote, “the product involves its organization”. Indeed, any dysfunction, weakening or abnormal behavior of a production system will have an impact, immediately or in the long term, on the quality and performance of the resulting product or service.
As we have seen previously, the evolution of a product throughout its lifecycle is highly dependent on the system’s situation that generates or transforms it. The observation is all the more critical as a production organization behaves like a nonlinear programmable network, with feedback loops and dynamic and time-varying interactions. This implies positioning control systems at the interaction level, knowing that due to the presence of phenomena sensitive to the initial conditions, the priority is no longer at the function level, but at the interaction level.
Companies must communicate and operate in a distributed way, in “network of networks” mode. The quality of communications and interactions is essential. It is therefore a question of having mobile teams (on the intellectual, cultural and physical levels, etc.) adaptable to unexpected situations, with non-selected partners, in innovative and unforeseen fields. This implies the formation of instant, multidisciplinary teams, which must operate without friction, using their creation, around common global objectives, in limited areas of freedom. The mobilization of such teams requires “sociable” entities, capable of working as a team in a spirit of cooperation and unfailing competition.
In self-organized systems, adaptability and the emergence of new orders are the strong points that allow them to react dynamically to changing demand conditions and needs.
With the advent of the Internet, this reactivity is permanent and responds to a constraint that is becoming more pressing every day and that we have great difficulty integrating into our processes: “faster, faster, etc.”. In this case, how can we find the right balance between the “credibility” of systems (the reliability and quality of systems are always built according to learning curves, well determined and which require time!) and the change in “disaster” mode (in the mathematical sense of the term which implies the notion of discontinuity and revolution by going through successive cycles or phases: disorder-reconfiguration-order)?
One approach is therefore to use the “dynamic stability” model, which is very well known in large companies. We will limit ourselves here to describing some aspects related to our new economic, social and cultural paradigm.
We all know that changes and innovations are the result of the profound control of transversal processes in a network of networking companies (a much more powerful concept than that of an extended company). More explicitly:
These particular constraints are difficult to address simultaneously. We will therefore be obliged to simplify the process by identifying the necessary subcultures, the criteria of competition and cooperation that will lead us to coopetition or comperation between vertical and transversal processes and by making subtle and balanced aggregations.
We mentioned the fact that the quality and performance of a process always requires time and effort.
The challenge is to reconcile these imperatives with those of e-business. This concerns the rapid implementation of a quality assurance and certification system (required for large volumes) or a global and total quality approach (as part of continuous process improvement and a dynamic customer-focused approach through mass customization).
In the first two cases, and to a lesser extent in the third case, it is a question of “hardening” and strictly controlling processes, using techniques such as six-sigma. This makes it difficult to adapt in a reactive and dynamic way to unstable and changing contexts.
Technologies are evolving rapidly, and there is a growing difficulty in adapting not only skills but also structures and infrastructure. How then can we reconcile resource adaptability, return on investment, dynamic reconfiguration of organizations and process control? How can all stakeholders be quickly involved in a global approach? This requires homogeneous and coherent modes of communication, thought, action, cooperation, creation, design, etc. How can we manage in real-time distributed production systems, process and workshop reconfigurations, relocations and company restructuring in a global and international environment? Dynamic stability requires a fine management of time, logistics and environmental constraints.
Taking into account all the constraints mentioned above, the implementation of the “dynamic stability” model must closely involve and integrate all the actors involved in the life-cycle of a product or service, whether they are R&D centers, clients, suppliers, distributed production systems, logistics, finance, or social and political actors.
In a didactic context, sociability (this word dates from the 17th Century) refers to the ability of a system to associate and bring together a number of similar entities and make them live agreeably and harmoniously at all times. By extension, sociability expresses the character of a group of living beings that promotes human relationships, particularly intellectual or social relationships [WIL 00]. This founding father of sociobiology explains in his book that most of the behavioral components of living organisms, and of course the conduct of human or social groups such as ants, have a genetic predestination. Thus, the sociability of groups of living beings is statically embedded in genes and becomes an integral part of their nature.
However, sociability can be seen as the manifestation of a dynamic process and the belonging of an entity to a larger group, and therefore to a social body, because there are mutual influences. These profoundly transform their own functioning and behavior. The emerging properties of this living group are of considerable power. Indeed:
The evolution of a complex system obeys a global objective, and it will therefore be organized to best meet its objectives in a given context and environment. This emergence of order corresponds to an attractor and it can be said, in another way, that the sociability of the system is considered as a sociobiological attractor.
Just as the notion of “interaction” is more important than that of “function” at the level of an agent, the emergence of a stable state or order takes precedence over the notion of predetermined order. In the first case, these are unpredictable events, and in the other case, these are calculable and predictable systems.
Thus, the concept of emergence is a fundamental part of the science of complexity and characterizes complex adaptive systems. This concept of the emergence and progressive and coherent organization of the parts of an interconnected system is based on two different approaches to the evolution of systems, the Platonicians and the Aristotelians:
However, in the life sciences, the proponents of each theory are opposed to the constitutive and emergent nature of phenomena related to complex systems. Indeed, thanks to molecular biology, the DNA of living organisms is observed in its smallest detail, genes are also isolated and attractive sites are identified. However, we are not yet able to explain, through the laws we know, how global properties emerge from such complex systems. Similarly, by focusing on the phenomena of organization and self-organization of organisms, we are still unable to explain certain points:
However, even though obscure points remain, everyone agrees that, in the phenomena of self-organization, if complex dynamic systems and living systems allow the emergence of structural patterns or stable forms, this is the result of the same mechanisms. Thus, the evolutionary models that have been developed by scientists are important to explain how orders are developed in Nature and in our industrial systems. Such models are fundamental to understanding the meaning of an organization, how a complex system is expressed and how global orders are organized, or to simulating the impact of a structural configuration on emerging orders and properties. However, they do not in any way allow us to understand and explain the profound meaning of emerging property, the meaning of life for example, but rather to understand and demystify the theory of self-organization.
Two possibilities are considered on how order emerges, on the genesis of biological or complex forms and on the theory of order and evolution:
This shows us that there are several ways to understand and envisage the evolution of a complex system, but that nothing should be neglected. In fact, the notions of self-organization, selection and evolution that we have described above are complementary and conclusive and this is what we do in everyday life:
The difficulty is therefore to know how an order is established in a complex structure. Everything depends of course on the behavior of nonlinear dynamic systems. Two theories are then evoked:
Complexity theory has a certain universality in that, in Nature, we are surrounded by complex systems with nonlinear functions and interactions. Such systems have the property of evolving in a divergent way, but in a limited space. For example, the number of states that a chaotic system can achieve may or may not be limited, but the extreme values are in a limited space. Similarly, a fractal structure has a dimension represented by a real number, but this is within certain limits. For example, a quasi-volume has a real dimension between integers 2 and 3.
In all complex systems, there is a powerful intrinsic dynamic. The objective is to migrate a system to the border of chaos to turn it upside down and acquire new properties, which we have also called orders. Indeed, these systems evolve according to an internal dynamic in an unpredictable way (because they cannot be calculated) and converge towards an emerging global structure. These considerations therefore lead us to define the following schema of principle in which two totally different approaches to complex system management are included.
These are in fact two visions of the world and two ways of understanding it:
In practice, it would be a mistake to apply only one of the approaches described above. These complement each other and highlight a feedback loop that operates accurately and continuously. The above diagram taken as a whole (right and left sides) forms a dynamic structural whole: one the left, being reductionist, the diversity of the system is reduced while defining strategies and tactics (optimal action plans), while one the right, concerning new forms, configurations and orders are generated. The dynamic is therefore intrinsic and comes from the internal evolution of the whole.
To study the self-organization mechanism, we consider systems whose purpose is not known a priori. More specifically, the notion of chance is integrated into the system, and disruption is part of the system’s constraints. The basic principle is that agents, or elements of the system, do not self-organize to ensure that a particular result is achieved, but only to adapt to external disturbances and to facilitate the achievement of an overall objective at the system-wide level. The elements that make up the system pursue an individual, not a global, objective. Cooperation between these elements provides an overall result that can be judged by an observer outside the system who knows the reasons why the system was designed. These lead to the development of robust, adaptive and tolerant systems.
Before analyzing the properties related to self-organization, it is necessary to recall notions related to its usefulness:
A concrete structure corresponds to a system’s stable state, i.e. a particular organization. Self-organization allows the transition, in an autonomous and reactive way, from one stable structure to another. The stability of a system’s structure depends on how long it remains stable despite disruptions that tend to destabilize it. Self-organization sometimes highlights phenomena of convergence towards particular structures. In this sense, it uses the concepts of attractors and basins of attraction, as defined in the chaos theory. This can be illustrated as follows:
In conclusion, a system with the capacity for self-organization has several states of equilibrium, i.e. particular organizations. Each particular organization is characterized by a set of different initial conditions that, when verified, converge the system to a corresponding stable organization. Most of the time, the self-organization system is between one or the other of its equilibrium states at the end of a time cycle that can be determined. It moves from one organizational state to another under the disorganizing pressure of its environment. The system that can adapt to changing circumstances by modifying the interaction structures between its components has the potential to achieve some consistency in environments with a high degree of uncertainty or change.
In a simple system, i.e. with a reduced number of elements, feedback loops ensure homeostasis. As a reminder, homeostasis is the property of a system to be able to stabilize around a given operating point. For example, a simple temperature sensor or detector, combined with a temperature controller, can act to keep the temperature of an enclosure between two limit values. The actual temperature value is then compared to a predefined threshold value and any excess is used to activate or deactivate the heating or cooling system.
More sophisticated and progressive approaches are also available, such as those used in the human body. The latter wishes to stabilize certain physiological constants at a given value, for example, to keep the temperature of the human body at a stable temperature of 37°C. Temperature sensors (neurons in the hypothalamus) can detect variations in the order of 0.01°C. Any excessive deviation makes it possible to activate compensation mechanisms that are not simply of the “go-no go” type but graduated according to the situation. Excessive body temperature triggers sweating and dilation of capillaries and certain blood vessels. Too low a temperature causes opposite effects, as well as shivering and an acceleration of the metabolism.
Many similar examples exist in chemistry, metabolism, the immune system, etc. where the system is able to regulate itself, i.e. to regulate its own functioning. In social systems, communication techniques between agents, based on game theory, make it possible to define very elaborate strategies whose evolutions and results are impossible to guess. Indeed, several elements specific to a complex system are taken into account:
Which advantages can we advocate for the method presented in this chapter?
Firstly, that tackling complexity is an opportunity to design and develop the sustainability function in complex systems. Secondly, that it leads to reaching a global and best fit objective by means of local rules. In fact, tackling complexity is a way to get a system evolving towards a chaotic attractor. While this obeys simple principles, it leads to disruptive change.
As a result, new patterns may emerge through the disruptions. Thanks to the diversity and adaptive properties at the local level, associated with aggregation ability, the system can eventually reach stable patterns.
Finally, thanks to interaction and feed-back loops within the system under development, it is possible to generate more sustainable and stable systems. And the benefits can be expressed in terms of flexibility, stability, reliability and controllability.