The next generation of macroergonomics: Integrating safety climate

To date little research has examined safety climate in relation to macroergonomics and how the two distinct sub-disciplines can be integrated to affect safety outcomes. The purpose of macroergonomics is to design a fully “harmonized” work system that improves numerous aspects of organizational performance and effectiveness, and this is accomplished by incorporating the foundational theoretical framework of sociotechnical systems theory (STS). Two broad subsystems within such a system are the personnel subsystem, the ways individuals perform tasks, and the technological subsystem, the tasks to be performed. Management is an important aspect of the personnel subsystem, and there is a growing body of research regarding supervisors’ influence over employee safety. One such area of research is safety climate, which is based on the perception of workers regarding safety and organizational practices. Two major factors of safety climate are management commitment to safety and communication pertaining to safety as a true priority from both top management and direct supervisors. This article describes the conceptual overlaps of macroergonomics and safety climate in order to present a conceptual model that integrates these domains using the framework of mesoergonomics. In conclusion, we discuss how this model can serve as a framework to guide the analysis and design of work systems and subsequent organizational interventions.     

Analysis of -omics data: Graphical interpretation- and validation tools in multi-block methods

As systems biology develops, various types of high-throughput -omics data become rapidly available. An increasing challenge is to analyze such massive data, interpret the results and validate the findings. Data analysis for most of the omics-techniques is in a fledgling immature stage. Alone the dimensionality of the data tables calls for new ways to reveal structure in the data, without cognitive overflow and excessive false discovery rate. Multi-block methods have been developed and adapted in order to find common variation patterns in data and depict these findings on graphical displays while providing tools to enhance the interpretation of the outcomes. In particular, multi-block methods based on latent variables are powerful tools to study block and global variation patterns, e.g. by inspecting block and global score plots. These methods can be used to achieve a graphical overview over sample and variable variation patterns in an efficient way. However, a visual detection of patterns may be subjective and, therefore, there is a need for validation tools. In this paper tools for validation of visually identified patterns in multi-block results are presented. Cross-validated estimates of Root Mean Square Error (RMSE) for block results are introduced for estimating the number of relevant PCs of the Consensus Principal Component Analysis (CPCA) models. Furthermore, important variables are identified by approximate t-tests based on Procrustes-corrected jackknifing. For the assessment of the stability of score patterns, block stability plots are introduced. Outliers can be revealed graphically on block and global level by stability plots.     

Validation of design methods: lessons from medicine

This paper discusses the validation of design methods. The challenges and opportunities in validation are illustrated by drawing an analogy to medical research and development. Specific validation practices such as clinical studies and use of models of human disease are discussed, including specific ways to adapt them to engineering design. The implications are explored for three active areas of design research: robust design, axiomatic design, and design decision making. It is argued that medical research and development has highly-developed, well-documented validation methods and that many specific practices such as natural experiments and model-based evaluations can profitably be adapted for use in engineering design research.     

Probabilistic design of water defense systems in The Netherlands

After the disaster in 1953, a statistical approach to the storm surge levels was chosen and an extrapolated storm surge level would be the basis for dike design. In recent decades, the development of reliability theory made it possible to assess the flooding risks taking into account the multiple failure mechanisms of a dike section and the length effect. It is pointed out that economic activity in the protected areas has grown considerably since the 1950s and that even more ambitious private and public investments, particularly in infrastructure, are planned. Moreover, the safety of a growing population is at stake. These considerations justify a fundamental reassessment of the acceptability of the flood risks.     

The elementary flux modes of a manufacturing system: a novel approach to explore the relationship of network structure and function

Elementary flux modes (EFMs) are a concept from Systems Biology, where they serve as an indicator of component relevance in metabolic networks. An elementary flux mode is a functionally relevant, non-decomposable path through a given network. In this paper, we apply elementary flux mode analysis to manufacturing systems, with the aim of using the number of EFMs as a predictor for resource significance in the manufacturing system. For this, we formulate a network representation of a manufacturing process, which allows us to define the manufacturing equivalent of a stoichiometric matrix to draw an analogy between metabolic and manufacturing systems. This, in turn, allows the computation of EFMs, which we conduct in a case-study for a real manufacturing system. We further show that the change of EFMs under resource breakdown is a good indicator of the average order lateness in the manufacturing system. In this way, EFMs provide insight into the relationship of network structure and function in manufacturing.     

Selection of porous materials in marine system design: The case of heat exchanger aboard ships

Porous materials are processed in various areas of material science and manufacturing. Furthermore, the varieties of porous materials ensure great advantages to designers. This paper proposes a decision aid mechanism based on fuzzy axiomatic design (FAD) to select adequate form of porous materials in marine systems design. It enables elimination and choice of suitable material alternatives in respect to two sets of attributes: generic material selection attributes (GMSA) and specific material selection attributes (SMSA). Furthermore, the paper specifically addressed use of porous materials in plate type heat exchanger design to demonstrate the proposed model. It is expected that the paper ensures a novel procedure for marine engineers and naval architectures in conceptual design process of marine systems.