Classification of Robustness and Resilience in Changeability

Turbulenzen im Fabrikumfeld stehen seit den Neunzigerjahren für einen permanenten Strukturwandel durch kontinuierliche Veränderungen, die Megatrends wie die Digitalisierung verstärken. Da die Prognosefähigkeit von Entwicklungen praktisch nicht mehr gegeben ist, basiert die Fabrikplanung auf Annahmen und geht im Gegensatz zu Entscheidungen unter Sicherheit mit Planungsrisiken einher. Um in diesem unsicheren Umfeld erfolgreich am Markt zu bestehen, benötigen Unternehmen veränderungsfähige Fabriken. Auf-grund der zunehmenden Organisation von Fabriken in Produktionsnetzwerken und einer steigenden Komplexität von Produktionsprozessen ist die Unsicherheit im Fabrikbetrieb zunehmend mit Risiken verbunden. Die Anzahl an störenden Ereignissen hat zugenommen, die zu einer Betriebsunterbrechung führen können. Deshalb haben vermehrt die Begriffe Robustheit und Resilienz Einzug in den Produktionskontext gehalten. Aktuell bleibt es unklar, wie genau die Fabrikplanung gestalterisch tätig werden kann, um dem Fabrikbetrieb den notwendigen Handlungsspielraum zu übertragen. Das Ziel dieses Artikels ist es deshalb, die Robustheit und Resilienz in den Kontext der Veränderungsfähigkeit einzuordnen, deren Konzepte bisher ausreichten, um Fabriken als elementares Strukturelement eines Produktionsnetzwerkes auf den Umgang mit turbulenten Einflüssen einzustellen.Turbulences in the factory environment have represented permanent structural transformation since the nineteen nineties through continuous changes that are intensified by megatrends such as digitalization. As the ability to forecast developments is practically non-existent, factory planning is based on assumptions and is associated with planning risks, in contrast to decisions made under certainty. In order to compete successfully on the market in this uncertain environment, companies need changeable factories. Due to the increasing organization of factories in production networks and a growing complexity of production processes, uncertainty in factory operation is increasingly associated with risks. The number of disturbing events has increased, which can lead to a business disruption. Therefore, the concepts of robustness and resilience have increasingly entered the production context. Currently, it remains unclear how exactly factory planning can take formative measures to give factory operation the necessary scope for action. Therefore, the goal of this article is to classify robustness and resilience in the context of changeability, whose concepts have been sufficient so far to adapt factories as an elementary structural element of a production network to handle turbulent influences

Utility of Cardiac Magnetic Resonance to assess association between admission hyperglycemia and myocardial damage in patients with reperfused ST-Segment Elevation Myocardial Infarction

International audienceAbstract: Aims: to investigate the association between admission hyperglycemia and myocardial damage in patients with ST-segment elevation myocardial infarction (STEMI) using Cardiac Magnetic Resonance (CMR). Methods: We analyzed 113 patients with STEMI treated with successful primary percutaneous coronary intervention. Admission hyperglycemia was defined as a glucose level >= 7.8 mmol/l. Contrast-enhanced CMR was performed between 3 and 7 days after reperfusion to evaluate left ventricular function and perfusion data after injection of gadolinium-DTPA. First-pass images (FP), providing assessment of microvascular obstruction and Late Gadolinium Enhanced images (DE), reflecting the extent of infarction, were investigated and the extent of transmural tissue damage was determined by visual scores. Results: Patients with a supramedian FP and DE scores more frequently had left anterior descending culprit artery (p = 0.02 and < 0.001), multivessel disease (p = 0.02 for both) and hyperglycemia (p < 0.001). Moreover, they were characterized by higher levels of HbA(1c) (p = 0.01 and 0.04), peak plasma Creatine Kinase (p < 0.001), left ventricular end-systolic volume (p = 0.005 and < 0.001), and lower left ventricular ejection fraction (p = 0.001 and < 0.001). In a multivariate model, admission hyperglycemia remains independently associated with increased FP and DE scores. Conclusion: Our results show the existence of a strong relationship between glucose metabolism impairment and myocardial damage in patients with STEMI. Further studies are needed to show if aggressive glucose control improves myocardial perfusion, which could be assessed using CMR

The best of non-invasive cardiac imaging in 1999.

International audienceThe term non-invasive and non-echographic myocardial imaging is used to describe the advances in nuclear cardiology and magnetic resonance imaging underlying the most recent developments in investigating the myocardium. The value of new techniques such as rapid CT scan and cardiological applications of the synchroton are described. The main clinical applications of these techniques in the present and future are reviewed, especially with regards to ischaemic heart disease

Welcome to the First International Workshop on Requirements Engineering for Explainable Systems (RE4ES)

Welcome to the First International Workshop on Requirements Engineering for Explainable Systems (RE4ES), where we aim to advance requirements engineering (RE) for explainable systems, foster interdisciplinary exchange, and build a community. On the one hand, we believe that the methods and techniques of the RE community can add much value to explainability research. On the other hand, we have to ensure that we develop techniques fitted to the needs of other communities.This first workshop explores synergies between the RE community and other communities already researching explainability.To this end, we have based our agenda on a mix of paper presentations from authors of different domains, one keynote from industry and one from research, as well as interactive activities to stimulate lively discussions

Muscle metabolism assessed by phosphorus-31 nuclear magnetic resonance spectroscopy after myocardial infarction in rehabilitated patients: a 1-year follow-up.

International audienceAbstract: BACKGROUND: The most common effect of postmyocardial infarction (post MI) rehabilitation is an increase of peak maximal oxygen consumption correlated with changes in calf muscle metabolism, but there are few data on follow-up after rehabilitation on skeletal muscle and maximal oxygen consumption. The purpose of this study was to investigate the respective modifications in skeletal muscle metabolism and peak oxygen consumption (VO2) occurring during a supervised rehabilitation program and 1 year after MI in patients free of heart failure. METHODS: Fifteen outpatients were studied prospectively after the acute phase of the MI, at the end of the rehabilitation program (2 months after the MI), and 1 year after. The rehabilitation comprised 20 sessions with three sessions per week. The program consisted of exercise training with bicycle, arm ergometer, and treadmill. The program also included respiratory exercises, psychological support, and counseling for secondary prevention of cardiovascular diseases. At each visit, a stress test on a bicycle ergometer was performed and the peak VO2 was measured. Phosphorus magnetic resonance spectroscopy of the gastrocnemius muscle was performed at rest and during a plantar flexion-type exercise against an adjustable load. Data were analyzed using analysis of variance and post-hoc test when appropriate. RESULTS: The mechanical power output measured during the bicycle exercise increased from 111 +/- 28 watts at the post MI test to 136 +/- 40 watts after rehabilitation (post rehab) and decreased to 125 +/- 36 watts at 1 year. The peak VO2 increased significantly (P < 0.05) from 22 +/- 7 ml/kg-1/min-1 (post MI) to 27 +/- 9 ml/kg-1/min-1 (post rehab), and decreased significantly to 24 +/- 8 ml/kg-1/min-1 (1 year). The mechanical power output measured in the magnet during the stress test increased from 2.22 +/- 0.13 watts (post MI) to 2.85 +/- 1.24 (post rehab), and stabilized at 2.78 +/- 1.10 watts at 1 year. At the highest workload attained in the three successive tests, the phosphocreatine/(phosphocreatine + inorganic phosphate) ratio rose significantly (P < 0.05) from 0.46 +/- 0.13 (post MI) to 0.51 +/- 0.13 (post rehab) and remained at 0.51 +/- 0.13 at 1 year. CONCLUSION: The improvement of the peak VO2 after training post MI is not maintained 1 year later. This decline is not accompanied by muscular metabolic abnormalities. This suggests that the muscle metabolism after MI remains normal, and that the long-term decrease of the peak VO2 reflects a global deconditioning that should be avoided by maintaining a long-term phase III rehabilitation program

Automatic fuzzy classification of the washout curves from magnetic resonance first-pass perfusion Imaging after myocardial infarction

International audienceAbstract: Objectives: We sought to investigate the diagnostic ability of cardiac magnetic resonance imaging (MRI) perfusion in acute reper-fused myocardial infarction. The study used fuzzy logic to automatically classify signal intensity-time curves from myocardial segments into 3 categories: normal, hypointense, and Hyperintense. Materials and Methods: Thirty-eight patients with myocardial infarction underwent short-axis cine-MRI and contrast-enhanced MRI to provide data on wall thickening and the transmural extent of infarction. Of these, 17 had a second cardiac MRI to ascertain the functional recovery in each segment. Results: The fuzzy logic based classification performs well (kappa = 0.87, P < 0.01) in comparison with a visual approach. Segments providing "hypo" curves do not recover (Delta = 0.11 SD = 0.96) whereas segments demonstrating the other curve types recover (Delta = 1 SD = 1.98 for "hyper" curves and Delta = 1.54 SD = 1.77 for "normal" curves). Conclusions: The proposed automatic signal intensity-time curve classification has a prognostic value when studying the functional recovery of pathologic segments and clearly identifies the no-reflow phenomenon known to induce poor recovery

Incomplete resolution of ST-segment elevation is associated with severe microvasculatory dysfunction evaluated by magnetic resonance imaging

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Comparison of the extent of dielayed-enhancement cardiac magnetic resonance imaging with and without phase-sensitive reconstruction at 3.0 T

International audienceAbstract: Objectives: To evaluate phase-sensitive reconstructed images versus magnitude images generated by an inversion recovery pulse sequence for the determination of myocardial infarct size in delayed-enhancement cardiac magnetic resonance (DE-CMR) at 3 T. Materials and Methods: Thirty patients were examined at 3 T and DE images were obtained 10 minutes after contrast agent administration using a phase-sensitive breath-hold segmented inversion recovery gradient echo sequence. From magnitude and phase images, the percentage of hyperenhanced myocardium was expressed. Contrast-to-noise ratio (CNR) measurements were performed in hyperenhanced and normal myocardium. Results: We observed excellent correlation and concordance between hyperenhanced myocardium determined on phase-sensitive reconstructed and magnitude images. The mean CNR values were significantly higher in phase-sensitive reconstructed images compared with magnitude images (10.5 +/- 5.4 vs. 6.1 +/- 4.8; P < 0.001). Conclusions: DE-CMR with phase-sensitive reconstruction at 3.0 T provides similar results to magnitude images, but with a significantly greater CNR between infarcted and normal myocardium

Visual estimation of the global myocardial extent of hyperenhancement on delayed contrast-enhanced MRI

International audienceAbstract: MRI with paramagnetic contrast agent allows the assessment of the extent of myocardial tissue injury after infarction. Visual segmental scoring has been widely used to define the transmural extent of myocardial infarction, but no attempt has been made to use visual scores in order to assess the percentage of the whole myocardium infarcted. By summing all the segmental scores using a 17-segment model, a global index of the size of the infarcted myocardium is easily obtained. The entire left ventricle of 60 patients with a recent myocardial infarction was scanned using an ECG-gated gradient echo sequence after injection of gadolinium contrast agent. The global score was defined as the sum of the scores on each segment, and expressed as a percentage of the maximum possible score. This index was compared with a planimetric evaluation of hyperenhancement, expressed as a percentage of the left ventricle myocardial volume. There is a good correlation between the two methods (r=0.91; y=1.06x+0.20), and the Bland-Altman plot shows a high concordance between the two approaches (mean of the differences =1.45%). A visual approach based on a 17-segment model can be used to evaluate the global myocardial extent of the hyperenhancement with similar results to planimetry

Should aortic stiffness be evaluated in thoracic aortic aneurysm/dissection relatives to prevent risks?

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