Proposition pour une Démarche de Modélisation des Processus

Le secteur aéronautique voit actuellement arriver de nouveaux types d'entrants, des systémiers innovants, en majorité des Petites et Moyennes Entreprises (PME), souhaitant développer et commercialiser de nouveaux moyens de transport. Des projets comme les dirigeables, les drones civils de transports de marchandises, les drones dits « taxi aérien », deviennent ainsi des préoccupations sérieuses pour tous les acteurs du marché où la sécurité des personnes et des infrastructures est un enjeu majeur. Dans ce cadre, le processus de certification, cœur de l'activité aéronautique, demeure une activité critique. Le secteur aéronautique est une industrie très structurée, organisée selon de nombreuses règles, normes et standards qui ne facilitent pas l'arrivée de ces nouveaux acteurs. Les PME concernées requièrent un support méthodologique pour les accompagner dans leurs développements et faire face à la complexité du marché. Nous proposons d'aborder la problématique par une approche d'ingénierie système basée sur les modèles et une modélisation hiérarchisée des processus d'entreprise

Systems Engineering and Project Management Process Modeling in the Aeronautics Context: Case Study of SMEs

The aeronautics sector is currently living an unprecedented growth largely due to innovative projects. In several cases, such innovative developments are being carried out by Small and Medium sized-Enterprises (SMEs). For instance, in Europe, a handful of SMEs are leading projects like airships, large civil drones, or flying cars. These SMEs have all limited resources, must make strategic decisions, take considerable financial risks and in the same time must take into account the constraints of safety, cost, time and performance as any commercial organization in this industry. Moreover, today, no international regulations fully exist for the development and certification of this kind of projects. The absence of such a precise and sufficiently detailed regulatory framework requires a very close contact with regulatory instances. But, SMEs do not always have sufficient resources and internal knowledge to handle this complexity and to discuss these issues. This poses additional challenges for those SMEs that have system integration responsibilities and that must provide all the necessary means of compliance to demonstrate their ability to design, produce, and operate airships with the expected level of safety and reliability. The final objective of our research is thus to provide a methodological framework supporting SMEs in their development taking into account recent innovation and institutional rules of the sector. We aim to provide a contribution to the problematic by developing a specific Model-Based Systems Engineering (MBSE) approach. Airspace regulation, aeronautics standards and international norms on systems engineering are taken on board to be formalized in a set of models. This paper presents the on-going research project combining Systems Engineering and Project Management process modeling and taking into account the metamodeling problematic

Une approche basée sur les modèles pour les PMEs innovantes de l’industrie aéronautique

Le marché de l'aviation fait face aujourd'hui à une croissance rapide des technologies innovantes. Les drones cargo, les taxis drones, les dirigeables, les ballons stratosphériques, pour n'en citer que quelques-uns, pourraient faire partie de la prochaine génération de transport aérien. Dans le même temps, les Petites et Moyennes Entreprises (PMEs) s'impliquent de plus en plus dans la conception et le développement de nouvelles formes de système aéroporté, passant du rôle traditionnel de fournisseur à celui de concepteur et intégrateur. Cette situation modifie considérablement la portée de la responsabilité des PMEs. En tant qu'intégrateurs, elles deviennent responsables de la certification des composants et du processus de fabrication, domaine dans lequel elles n’ont encore que peu d'expérience. La certification, qui requiert une connaissance très spécifique des réglementations, des normes et standards, demeure un processus obligatoire et une activité critique pour les entreprises de l'industrie aéronautique. C’est aussi un défi majeur pour les PMEs qui doivent assumer cette responsabilité de certification avec des moyens limités. Dans cette thèse, deux besoins majeurs sont identifiés: le soutien méthodologique n'est pas facilement disponible pour les PMEs; et les exigences de certification ne sont pas facilement compréhensibles et adaptables à chaque situation. Nous examinons donc des voies alternatives pour réduire la complexité de la situation des PMEs. L'objectif est de fournir un soutien afin qu'elles puissent être plus efficaces pour comprendre et intégrer les règles, les législations et les lignes directrices à leurs processus internes de manière plus simple. Cette thèse propose ainsi une approche méthodologique pour soutenir ces organisations. Développée en étroite collaboration avec une PME française, l'approche est composée d'un ensemble de modèles (métamodèle, modèles structurels et comportementaux) couverts par un mécanisme de gouvernance.The aviation market is facing nowadays a fast growth of innovative airborne systems. Drone cargo, drone taxi, airships, stratospheric balloons, to cite a few, could be part of the next generation of air transportation. In the same time, Small and Medium-sized Enterprises (SMEs) are becoming more and more involved in designing and developing new forms of air transportation, transitioning from the traditional role of supplier to those of system designer and integrator. This situation changes drastically the scope of SMEs' responsibility. As integrators they become responsible for certification of the components and the manufacturing process, an area in which they have little experience. Certification mandates very specific knowledge, regarding the regulations, norms and standards. Certification is a mandatory process and a critical activity for the enterprises in the aerospace industry. It constitutes a major challenge for SMEs who have to take on this certification responsibility with only limited resources. In this thesis, two major needs are identified: methodological support is not easily available for SMEs; and certification requirements are not easily comprehensive and adaptable to each situation. We examine alternate paths, reducing the complexity and bringing one step closer to solving the problem for the innovative SMEs. The objective is to provide support so that they can be more efficient to comprehend and integrate rules, legislations and guidelines to their internal processes in a simpler way. This thesis proposes then a methodological approach to support such organisation. Developed in close cooperation with a French SME in this situation, the approach is composed of a set of models (metamodel, structural, and behavioural models) covered by a certification governance mechanism

Modélisation des processus de développement pour les petites et moyennes entreprises du secteur aéronautique

Récemment, des Petites et Moyennes Entreprises (PME) innovent en proposant de nouveaux moyens de transport aériens. Ces projets posent des questions importantes par rapport à la réglementation alors que celle-ci n’est pas complètement disponible pour ces types de développement. Le processus de certification, activité critique pour toute entreprise du marché aéronautique, demeure un enjeu pour ces entreprises non familières avec l’ensemble des contraintes imposées. Les PME concernées, démunies face à la complexité du marché, requièrent un support méthodologique. Nous proposons dans notre recherche de répondre à cette demande spécifique par une approche d'ingénierie système basée sur les modèles et une modélisation hiérarchisée des processus d'entreprise

Severity of COVID-19 and survival in patients with rheumatic and inflammatory diseases: data from the French RMD COVID-19 cohort of 694 patients

International audienceObjectives: There is little known about the impact of SARS-CoV-2 on patients with inflammatory rheumatic and musculoskeletal diseases (iRMD). We examined epidemiological characteristics associated with severe disease, then with death. We also compared mortality between patients hospitalised for COVID-19 with and without iRMD.Methods: Individuals with suspected iRMD-COVID-19 were included in this French cohort. Logistic regression models adjusted for age and sex were used to estimate adjusted ORs and 95% CIs of severe COVID-19. The most significant clinically relevant factors were analysed by multivariable penalised logistic regression models, using a forward selection method. The death rate of hospitalised patients with iRMD-COVID-19 (moderate-severe) was compared with a subset of patients with non-iRMD-COVID-19 from a French hospital matched for age, sex, and comorbidities.Results: Of 694 adults, 438 (63%) developed mild (not hospitalised), 169 (24%) moderate (hospitalised out of the intensive care unit (ICU) and 87 (13%) severe (patients in ICU/deceased) disease. In multivariable imputed analyses, the variables associated with severe infection were age (OR=1.08, 95% CI: 1.05-1.10), female gender (OR=0.45, 95% CI: 0.25-0.80), body mass index (OR=1.07, 95% CI: 1.02-1.12), hypertension (OR=1.86, 95% CI: 1.01-3.42), and use of corticosteroids (OR=1.97, 95% CI: 1.09-3.54), mycophenolate mofetil (OR=6.6, 95% CI: 1.47-29.62) and rituximab (OR=4.21, 95% CI: 1.61-10.98). Fifty-eight patients died (8% (total) and 23% (hospitalised)). Compared with 175 matched hospitalised patients with non-iRMD-COVID-19, the OR of mortality associated with hospitalised patients with iRMD-COVID-19 was 1.45 (95% CI: 0.87-2.42) (n=175 each group).Conclusions: In the French RMD COVID-19 cohort, as already identified in the general population, older age, male gender, obesity, and hypertension were found to be associated with severe COVID-19. Patients with iRMD on corticosteroids, but not methotrexate, or tumour necrosis factor alpha and interleukin-6 inhibitors, should be considered as more likely to develop severe COVID-19. Unlike common comorbidities such as obesity, and cardiovascular or lung diseases, the risk of death is not significantly increased in patients with iRMD

Severity of COVID-19 and survival in patients with rheumatic and inflammatory diseases: data from the French RMD COVID-19 cohort of 694 patients

International audienceObjectives: There is little known about the impact of SARS-CoV-2 on patients with inflammatory rheumatic and musculoskeletal diseases (iRMD). We examined epidemiological characteristics associated with severe disease, then with death. We also compared mortality between patients hospitalised for COVID-19 with and without iRMD.Methods: Individuals with suspected iRMD-COVID-19 were included in this French cohort. Logistic regression models adjusted for age and sex were used to estimate adjusted ORs and 95% CIs of severe COVID-19. The most significant clinically relevant factors were analysed by multivariable penalised logistic regression models, using a forward selection method. The death rate of hospitalised patients with iRMD-COVID-19 (moderate-severe) was compared with a subset of patients with non-iRMD-COVID-19 from a French hospital matched for age, sex, and comorbidities.Results: Of 694 adults, 438 (63%) developed mild (not hospitalised), 169 (24%) moderate (hospitalised out of the intensive care unit (ICU) and 87 (13%) severe (patients in ICU/deceased) disease. In multivariable imputed analyses, the variables associated with severe infection were age (OR=1.08, 95% CI: 1.05-1.10), female gender (OR=0.45, 95% CI: 0.25-0.80), body mass index (OR=1.07, 95% CI: 1.02-1.12), hypertension (OR=1.86, 95% CI: 1.01-3.42), and use of corticosteroids (OR=1.97, 95% CI: 1.09-3.54), mycophenolate mofetil (OR=6.6, 95% CI: 1.47-29.62) and rituximab (OR=4.21, 95% CI: 1.61-10.98). Fifty-eight patients died (8% (total) and 23% (hospitalised)). Compared with 175 matched hospitalised patients with non-iRMD-COVID-19, the OR of mortality associated with hospitalised patients with iRMD-COVID-19 was 1.45 (95% CI: 0.87-2.42) (n=175 each group).Conclusions: In the French RMD COVID-19 cohort, as already identified in the general population, older age, male gender, obesity, and hypertension were found to be associated with severe COVID-19. Patients with iRMD on corticosteroids, but not methotrexate, or tumour necrosis factor alpha and interleukin-6 inhibitors, should be considered as more likely to develop severe COVID-19. Unlike common comorbidities such as obesity, and cardiovascular or lung diseases, the risk of death is not significantly increased in patients with iRMD

COVID-19 outcomes in patients with inflammatory rheumatic and musculoskeletal diseases treated with rituximab: a cohort study

International audienceBackground: Various observations have suggested that the course of COVID-19 might be less favourable in patients with inflammatory rheumatic and musculoskeletal diseases receiving rituximab compared with those not receiving rituximab. We aimed to investigate whether treatment with rituximab is associated with severe COVID-19 outcomes in patients with inflammatory rheumatic and musculoskeletal diseases.Methods: In this cohort study, we analysed data from the French RMD COVID-19 cohort, which included patients aged 18 years or older with inflammatory rheumatic and musculoskeletal diseases and highly suspected or confirmed COVID-19. The primary endpoint was the severity of COVID-19 in patients treated with rituximab (rituximab group) compared with patients who did not receive rituximab (no rituximab group). Severe disease was defined as that requiring admission to an intensive care unit or leading to death. Secondary objectives were to analyse deaths and duration of hospital stay. The inverse probability of treatment weighting propensity score method was used to adjust for potential confounding factors (age, sex, arterial hypertension, diabetes, smoking status, body-mass index, interstitial lung disease, cardiovascular diseases, cancer, corticosteroid use, chronic renal failure, and the underlying disease [rheumatoid arthritis vs others]). Odds ratios and hazard ratios and their 95% CIs were calculated as effect size, by dividing the two population mean differences by their SD. This study is registered with ClinicalTrials.gov, NCT04353609.Findings: Between April 15, 2020, and Nov 20, 2020, data were collected for 1090 patients (mean age 55·2 years [SD 16·4]); 734 (67%) were female and 356 (33%) were male. Of the 1090 patients, 137 (13%) developed severe COVID-19 and 89 (8%) died. After adjusting for potential confounding factors, severe disease was observed more frequently (effect size 3·26, 95% CI 1·66-6·40, p=0·0006) and the duration of hospital stay was markedly longer (0·62, 0·46-0·85, p=0·0024) in the 63 patients in the rituximab group than in the 1027 patients in the no rituximab group. 13 (21%) of 63 patients in the rituximab group died compared with 76 (7%) of 1027 patients in the no rituximab group, but the adjusted risk of death was not significantly increased in the rituximab group (effect size 1·32, 95% CI 0·55-3·19, p=0·53).Interpretation: Rituximab therapy is associated with more severe COVID-19. Rituximab will have to be prescribed with particular caution in patients with inflammatory rheumatic and musculoskeletal diseases