Bioprocess development generates extensive datasets from different unit operations and sources (e.g. time series, quality measurements). The development of such processes can be accelerated by ...evaluating all data generated during the experimental design. This can only be achieved by having a clearly defined data logging and analysis strategy. The latter is described in this manuscript. It consists in a combination of a feature based approach along with principal component analysis and partial least square regression.
Application of this combined strategy is illustrated by applying it in an upstream processing (USP) case study. Data from the development and optimization of an animal component free USP of Sabin inactivated poliovirus vaccine (sIPV) was evaluated. During process development, 26 bioreactor runs at scales ranging from 2.3 to 16 L were performed. Several operational parameters were varied, and data was routinely analyzed following a design of experiments (DoE) methodology.
With the strategy described here, it became possible to scrutinize all data from the 26 runs in a single data study. This included the DoE response parameters, all data generated by the bioreactor control systems, all offline data, and its derived calculations. This resulted in a more detailed, reliable and exact view on the most important parameters affecting bioreactor performance.
In this case study, the strategy was applied for the analysis of previously produced data. Further development will use this data analysis methodology for continuous enhancing and accelerating process development, intensified DoE and integrated process modelling.
Many open source software (OSS) products today are market leaders, 1 which suggests that the development of OSS is key to the growth of the software industry. OSS projects increasingly tend to be ...incorporated in large-scale projects or "software ecosystems" to reduce effort and accelerate innovation.
Purpose
The purpose of this paper is to apply the Six Sigma DMAIC methodology in order to reduce the rejections experienced in the manufacturing of the doors belonging to a telecommunication cabinet.
...Design/methodology/approach
The process involved joining of sheet metal and hinge using welding operations with the help of a fixture. The methodology used is the structured DMAIC method in order to identify the root cause for the rejections and solve it.
Findings
The paper provides insights about the identification of the root cause for the defects and the solution to overcome it, and also the benefits that were obtained as a result of the application of the solution.
Research limitations/implications
This methodology has been applied to the variation observed in the dimensions of a particular component to be welded with a main part. This approach can be used to find such dimensional variations.
Practical implications
This study has been successfully carried out in a medium-scale industry which has total quality management in practice.
Originality/value
Six Sigma DMAIC was necessary for the identification and reduction of the defects which arose in the sheet metal and welding operations, and had to be resolved in order to increase the bottom-line.
Background
As lignite mining protests and #FridaysForFuture demonstrations gained momentum in Germany and further protests have been developing over time, this paper investigates the various causes ...and effects of the country’s energy transition. Society and politics alongside economic, environmental, and technological developments have led to a profound and continuous transformation of the energy system, a transformation which is remarkable in terms of reach and speed for an economy of the size of Germany’s. Pressure to transform the country’s entire energy system even faster has recently been levelled due to the Russian invasion of Ukraine.
Results
From the perspective of the different pillars of sustainability and various stakeholder groups, this paper discusses the influences and their interdependencies towards the status quo of the German energy sector. We have used the cause-and-effect analysis method to answer the question of why major energy generators in Germany are still struggling with the energy transition, as well as the question of why a strategy towards more sustainability is needed to maintain Germany’s industrial strength in the long run. We found that energy transition in Germany is substantially driven by society, which pushes political decisions that lead to an economic transition, while environmental incidents are only triggers for further societal and political doings. Furthermore, technological developments fulfil only needs and do not necessarily hurry ahead of time.
Conclusions
Overall, the article creates a profound understanding of the factors influencing the German energy transition which is deeply embedded in the European energy system.
Purpose - The paper seeks to support a better understanding of the types (or processes) of reflexivity which may be involved in the practice of organizational research, and the implications of ...reflexive practice for organizational researchers.Design methodology approach - A characterization of reflexivity as a process is developed from extant research, in four steps. First, the principal dimensions of reflexivity - reflection and recursion - are identified and delineated. Second, recursion is shown to have two modes, active and passive. Third, reflection is shown to have both closed, self-guided and open, relational modes. Fourth, through integrating the detailed characterizations of each of the dimensions, different types of reflexivity are identified and defined.Findings - The paper shows how different types of reflexivity may be experienced sequentially, as a progressive process, by organizational researchers. Implications for research practice are derived from a consideration of this process.Originality value - The paper develops a novel conceptualization of reflexivity as a process with individual and relational aspects. This conceptualization supports important insights for the conduct and legitimation of reflexive research.
Mergers and acquisitions (M&A) are an internationally adopted expansion strategy, but not every case can be successfully executed nor achieved the intended post-expansion results. Most studies focus ...on M&A wave or post-M&A integration, yet this article focuses on pre-M&A analysis and planning. An M&A evaluation and prioritization model (MAEPM) is proposed to assist decision makers in a more objective and effective manner so that to implement and execute each M&A deal with the aim of maximizing the success rate rather than any other irrelevant reasons. Risk analysis, fuzzy critical path analysis, cost–benefit evaluation, as well as decision rule and prioritization were developed and integrated, which provide insight into M&A evaluation and serve as indicators. Eleven case studies were conducted to verify the MAEPM and the results generated from the MAEPM were compared with the actual results that confirmed the MAEPM is significant and plausible. The novel MAEPM is confirmed to be reliable that enables firms to select the most winning M&A deal(s) to be made according to the availability of resources and capital and thus enhance the success rate of M&A.
Purpose - The adoption of the ISO 9001 Quality Management Systems Standard has proven to be a persistent and growing phenomenon in services and manufacturing, yet to date little research has been ...done that can indicate how far improved business performance can be attributed to it rather than counter-intuitive causes. The paper aims to examine the evidence for the causal links between quality management system certification and improved performance in the empirical literature.Design methodology approach - A method is proposed for testing how far performance improvement can be attributed to quality management system certification and how far attribution to other causes applies. This method is illustrated on a longitudinal study and then utilised to interpret the findings of other longitudinal studies.Findings - It is concluded that although there is some evidence to indicate that quality management system certification has some causal influence on business performance, there is also evidence for the existence of a substantial mechanism whereby better performing firms self-select to adopt certification. Possible causes for this mechanism are discussed.Research limitations implications - The existence of a self-select mechanism has profound implications for interpreting business performance achievements associated with quality management system certification because the benefits found may well be inflated by its presence. The authors suggest that richer theory is needed that can incorporate bi-directional influences and new research is needed to explore the underlying causes of adoption selection effects.Originality value - The paper provides researchers with a method for testing and discussing causation influences on results. It provides evidence that a substantial part of the association found in the research on quality management system certification and business benefits may be due to counterintuitive causes.
Based on available sources, the frequency of explosions in the marine engine’s starting air manifolds is determined under real conditions. A cause-and-effect analysis of these explosions and their ...root causes are identified. A probabilistic model of an explosion in the starting air manifold of a marine engine is built using a fault tree analysis (FTA). Using a stochastic simulation (Monte Carlo) and an exact reliability availability calculation (ERAC) algorithm applied to the developed FTA model, selected reliability measures are calculated to describe an incident of the top event, which involves an explosion in the starting air manifold. For such an event, several factors are calculated, including the availability, the unavailability, the failure frequency, and the mean time to failure. Based on the simulations, the relative frequency of the top event is determined in relation to the number of events that can simultaneously occur and lead to an explosion. The significance of each basic event is assessed to determine their individual impact on the explosion incident. The following measures are used: the Vesely–Fussell measure of importance, the criticality measure of importance, the Birnbaum measure of reliability importance, and the Birnbaum measure of structural importance. The results of the analysis show that defective starting air valves are most responsible for the explosion incident in the starting air manifold. During the first year of the ship’s operation, the reliability does not fall below the value of 0.65, while the mean time to failure and the top event frequency are statistically at the level of one explosion per approximately 2.28 years of continuous engine operation.
Sustainability is a growing concern for manufacturing companies, as they are major contributors to pollution and consume a substantial portion of the world´s natural resources. Sustainable ...manufacturing can reduce waste, conserve energy and increase resource efficiency. However, one of the main challenges facing manufacturing organisations to put sustainability into practice is the lack of understanding of the cause-and-effect relationships between critical indicators of sustainable manufacturing. To overcome this challenge, a novel, rigorous and integrated framework, composed of four quantitative methods, is proposed to analyse critical indicators of sustainable manufacturing. The analysis is based on responses from both academic and industry experts. These four methods including DEMATEL (decision-making trial and evaluation laboratory), the MMDE (maximum mean de-entropy) algorithm, ISM (interpretive structural modelling) and SEM (structural equation modelling) are uniquely integrated to present statistically validated relationships between critical indicators using information on varying degrees of relationship between them. The final cause-and-effect models for the respondent groups (i.e., researchers and industry experts) are further validated through gathering the viewpoints of a researcher and an industry practitioner for its robustness. The novelty of our research lies in: (1) proposing a novel and integrated rigorous quantitative framework combined with qualitative research method; (2) applying the proposed framework to analyse contextual relationships between critical indicators of implementing sustainability, in the manufacturing sector as a whole, which to the best of authors’ knowledge is the first of its kind; and (3) comparing and contrasting results of researchers and industry practitioners’ groups along with a check of their validation and robustness.
Air–liquid interface (ALI) systems have been widely used in recent years to investigate the inhalation toxicity of many gaseous compounds, chemicals, and nanomaterials and represent an emerging and ...promising in vitro method to supplement in vivo studies. ALI exposure reflects the physiological conditions of the deep lung more closely to subacute in vivo inhalation scenarios compared to submerged exposure. The comparability of the toxicological results obtained from in vivo and in vitro inhalation data is still challenging. The robustness of ALI exposure scenarios is not yet well understood, but critical for the potential standardization of these methods. We report a cause-and-effect (C&E) analysis of a flow through ALI exposure system. The influence of five different instrumental and physiological parameters affecting cell viability and exposure parameters of a human lung cell line in vitro (exposure duration, relative humidity, temperature, CO2 concentration and flow rate) was investigated. After exposing lung epithelia cells to a CeO2 nanoparticle (NP) aerosol, intracellular CeO2 concentrations reached values similar to those found in a recent subacute rat inhalation study in vivo. This is the first study showing that the NP concentration reached in vitro using a flow through ALI system were the same as those in an in vivo study.
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