Paulien M. Herder

System and Actor Perspectives on Sociotechnical Systems

This paper addresses the complexity of analyzing and designing sociotechnical systems: systems that involve both complex physical-technical systems and networks of interdependent actors. It is shown that, although a hard system perspective and an actor perspective differ greatly in terms of terminology, methods, and applicability, they also show surprisingly many similarities. By building upon the similarities and differences of the two dominant perspectives, this paper then goes on to show that the modeling and intervention possibilities in both perspectives differ to a great extent. The emerging systems-of-systems discipline generally calls for an ldquointegrationrdquo of both perspectives in order to model and design these complex sociotechnical systems, but in this paper, it is argued and shown that full integration is not the preferred way to go. Instead, the emerging discipline should strive to facilitate the use of both perspectives alongside each other in a sensible way and, thereby, not discard the strengths of either perspective.

Integrating reliability optimization into chemical process synthesis

Abstract The growing need to achieve high availability for large integrated chemical process systems demands higher levels of system reliability at the operational stage. In these circumstances, it has become critical to consider the reliability aspects of a system and its components at the design stage. Traditional reliability/availability analysis methods and maintenance optimization frameworks, commonly applied at the design stage, are limited in their application, as in most of these methods the designer is required to specify the process system components, their connectivity and their reliabilities a priori . As a result, these traditional methods do not provide the flexibility to reconfigure a process or select initial reliabilities of equipment in a way that maximizes the inherent plant availability at the design stage. In this paper, we developed an optimization framework by combining the reliability optimization and process synthesis challenges and the combined optimization problem is posed as a mixed integer non-linear programming optimization problem. The proposed optimization framework features an expected profit objective function, which takes into account the trade-off between initial capital investment and the annual operational costs by supporting appropriate estimation of revenues, investment cost, raw material and utilities cost, and maintenance cost as a function of the system and its component availability. The effectiveness and usefulness of the proposed optimization framework is demonstrated for the synthesis of the hydrodealkylation process (HDA) process.

Designing Socio-Technical Systems

Publisher Summary A diverse body of research in engineering and the social sciences documents the working of systems that require technical artifacts and social arrangements to function. Single plants, firms, or entire industrial sectors constitute socio-technical systems if technological components and social arrangements are so intertwined that their design requires the joint optimization of technological and social variables. Social and technical subsystems are intertwined and each has multiple layers that are designed and evolve on different time scales. Multi-level systems have been more widely studied by social scientists than by engineers in institutional approaches. Design decisions are made at all layers but the scope for such choices is generally broader at the lower layers. Consequently, in higher layers of the socio-technical system, deliberate design decisions become less prevalent and emergent characteristics become more important. Continuous and specific design choices are made at the operational and management layer. These design decisions are constrained by design choices at the governance layer. Design decisions are made at that layer although the decision-makers typically are different.

Follow the rainbow: a knowledge management framework for new product introduction

This paper describes the development of a knowledge management framework for the “new product introduction process” of Motorola. Motorola operates in a very dynamic business with short product cycles, and has a clear need, therefore, to leverage the knowledge available worldwide. After developing a theoretical framework that reflected Motorola’s business processes, a large‐scale survey among workers at different locations in the world was conducted. The survey results were used for the design of a knowledge management framework, which supports sharing of various types of knowledge on different business levels.

A concurrent engineering approach to chemical process design

Abstract Much confusion still surrounds the concurrent engineering design concept in the chemical engineering world. The conventional hierarchical design method is compared to the concurrent engineering concept, and it is shown that the CE concept particularly improves the way a chemical design engineer deals with “external factors” that influence a process design. A framework is introduced to easily identify and classify these external factors. Through a number of industrial case studies, the current design methods have been analyzed, and improvements are identified. The flexibility of the plant can be improved by using a concurrent approach.

Industrial application of RAM modeling: Development and implementation of a RAM simulation model for the Lexan® plant at GE Industrial, Plastics

A RAM (reliability, availability and maintenance) model has been built for the GE Industrial, Plastics Lexan® plant in Bergen op Zoom, The Netherlands. It was based on a Reliability Block Diagram with a Monte Carlo simulation engine. The model has been validated against actual plant data from two different sources, and against local expert opinions, resulting in a satisfactory simulation model. The model was used to assess two key decisions that were (to be) made by GE Industrial, Plastics concerning operation and shutdown policies of the plant. The model results showed that the operation and maintenance could be further improved, and that in doing so the annual production loss could be reduced further.

An Evaluation of the Pugh Controlled Convergence Method

This paper evaluates a method known as Pugh Controlled Convergence and its relationship to recent developments in design theory. Computer executable models are proposed simulating a team of people involved in iterated cycles of evaluation, ideation, and investigation. The models suggest that: 1) convergence of the set of design concepts is facilitated by the selection of a strong datum concept; 2) iterated use of an evaluation matrix can facilitate convergence of expert opinion, especially if used to plan investigations conducted between matrix runs; and 3) ideation stimulated by the Pugh matrices can provide large benefits both by improving the set of alternatives and by facilitating convergence. As a basis of comparison, alternatives to Pugh’s methods were assessed such as using a single summary criterion or using a Borda count. The models we developed suggest that Pugh’s method, under a substantial range of assumptions, results in better design outcomes than those from these alternative procedures.© 2007 ASME

Long term optimization of asset replacement in energy infrastructures

In the western energy distribution systems, the assets are relatively old. Distribution companies expect a large number of assets to fail because they reach their end of life in 10 to 30 years from now. Those failed assets will have to be replaced, which would potentially double the total workload in this 20 year period. Unfortunately, half of the work force is expected to retire in the next 10 years. This combination of trends presents the distribution companies with a number of questions. What is the expected number of assets to fail due to age problems? What would be the cost-optimal preventive replacement strategy for those assets? What is the feasibility of this strategy, given the constraints caused by the employee shortage? What are alternatives to overcome those limitations? We have explored those questions with a System Dynamics model, based on real data from a distribution company. We determined that an increase in the number of failures is to be expected in the coming 10-20 years, even under a cost-optimal replacement strategy. However, because of employee shortages, this cost-optimal strategy cannot be executed with the current Human Resource policies, worsening the problem. Hence, optimal strategies would not only have to define asset replacement programs but also a matching HR policy.

Quality criteria for process design in the design process — industrial case studies and an expert panel

Abstract Research into the design processes at industrial operating companies and engineering contractors revealed that no explicit, well-defined set of quality criteria is available to judge the final design. A well-defined set of quality factors might reduce the number of iteration loops in the design process and might also support the designer in achieving a better final design. A number of industrial case studies and a meeting with an expert-panel provided useful insights into a possible set of quality criteria, and revealed explicit as well as implicit, ill-defined quality criteria. The criteria as stated in the ‘Basis of Design’ were seen as the most important quality criteria in industrial practice, however many other implicit and ill-defined criteria were also found to play an important role. The expert-panel, which consists of professionals from industry and from academia, discussed the subject thoroughly using an electronic meeting room. Many quality criteria were formulated and many ill-defined and qualitative aspects were mentioned. The expert-panel established a ranking of the quality criteria and ill-defined criteria ranked high in the established hierarchy. An indication was given of when the most important quality criteria were introduced into the design process. This resulted in identifying a need to consider quality criteria earlier in the design process. According to the expert panel, this is still very hard to achieve in practice, therefore a system, which will be implemented as a software tool, is being developed. The tool is designed to support the designer in defining the set of relevant explicit and implicit quality criteria, and in considering these quality criteria from the beginning to the end of the design process.

Recycling industrial waste heat for sustainable district heating: a multi-actor perspective

Addressing the climate change and energy scarcity problems are two of the most complex sustainability challenges facing not only scientists, but also policy makers. Attempts at tackling these issues should be approached from two fronts: by increasing the energy efficiency (demand side) and by promoting the usage of renewables and non-Greenhouse Gases emitting energy sources (supply side). Usually, there is an agreement among stakeholders about sustainability in general, but there is a notable disagreement about how to achieve it. Thus, this paper proposes a multi-actor modelling and analysis approach as a way forward in systematically studying the system and actors dynamics – this is necessary in order to garner cooperation that will not only get such sustainability projects started, but that will also keep them going. A case study was employed to study the feasibility of using residual industrial heat for sustainable District Heating System. The result of the multi-actor analysis reveals that the Municipality (the initiator of the project) will have far greater success if it includes the perspectives of all the different stakeholders and encourage their participation from the early phases of project design and development.