Search results for: Frédérique Roffet
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 4

Search results for: Frédérique Roffet

4 Validating Condition-Based Maintenance Algorithms through Simulation

Authors: Marcel Chevalier, Léo Dupont, Sylvain Marié, Frédérique Roffet, Elena Stolyarova, William Templier, Costin Vasile

Abstract:

Industrial end-users are currently facing an increasing need to reduce the risk of unexpected failures and optimize their maintenance. This calls for both short-term analysis and long-term ageing anticipation. At Schneider Electric, we tackle those two issues using both machine learning and first principles models. Machine learning models are incrementally trained from normal data to predict expected values and detect statistically significant short-term deviations. Ageing models are constructed by breaking down physical systems into sub-assemblies, then determining relevant degradation modes and associating each one to the right kinetic law. Validating such anomaly detection and maintenance models is challenging, both because actual incident and ageing data are rare and distorted by human interventions, and incremental learning depends on human feedback. To overcome these difficulties, we propose to simulate physics, systems, and humans -including asset maintenance operations- in order to validate the overall approaches in accelerated time and possibly choose between algorithmic alternatives.

Keywords: degradation models, ageing, anomaly detection, soft sensor, incremental learning

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3 Foodborne Pathogens in Different Types of Milk: From the Microbiome to Risk Assessment

Authors: Pasquali Frederique, Manfreda Chiara, Crippa Cecilia, Indio Valentina, Ianieri Adriana, De Cesare Alessandra

Abstract:

Microbiological hazards can be transmitted to humans through milk. In this study, we compared the microbiome composition and presence of foodborne pathogens in organic milk (n=6), organic hay milk (n=6), standard milk (n=6) and high-quality milk (n=6). The milk samples were collected during six samplings between December 2022 to January 2023 and between April and May 2024 to take into account seasonal variations. The 24 milk samples were submitted to DNA extraction and library preparation before shotgun sequencing on the Illumina HiScan™ SQ System platform. The total sequencing output was 600 GB. In all the milk samples, the phyla with the highest relative abundances were Pseudomonadota, Bacillota, Ascomycota, Actinomycetota and Apicomplexa, while the most represented genera were Pseudomonas, Streptococcus, Geotrichum, Acinetobacter and Babesia. The alpha and beta diversity indexes showed a clear separation between the microbiome of high-quality milk and those of the other milk types. Moreover, in the high-quality milk, the relative abundance of Staphylococcus (4.4%), Campylobacter (4.5%), Bacillus (2.5%), Enterococcus (2.4%), Klebsiella (1.3%) and Escherichia (0 .7%) was significantly higher in comparison to other types of milk. On the contrary, the relative abundance of Geotrichum (0.5%) was significantly lower. The microbiome results collected in this study showed significant differences in terms of the relative abundance of bacteria genera, including foodborne pathogen species. These results should be incorporated into risk assessment models tailored to different types of milk.

Keywords: raw milk, foodborne pathogens, microbiome, risk assessment

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2 Shelf Life of Frozen Processed Foods for Extended Durability

Authors: Manfreda Gerardo, Pasquali Frederique, Pepe Tiziana, Anastasio Aniello, Ianieri Adriana

Abstract:

The aim of the research was to evaluate the shelf life of a REPFED’s product (lasagna alla bolognese), developed as a product to be marketed fresh after defrosting. Three different samples were prepared: A, B and C, which presented differences in relation to the recipe, pasteurization technique and packaging on which the trend of the shelf-life indicator parameters was evaluated during a period of prolonged shelf life. The analytical plan involved the measurement of microbiological, chemical-physical and organoleptic parameters over 7 moments of storage selected in a period of 33 days. CBT, LAB, enterobacteria, E. coli, yeasts, molds, S. coagulase positive, B. cereus, Salmonella spp and L. monocytogenes, pH, Aw, Kreiss test, peroxides, atmosphere inside the packages, and organoleptic characteristics were determined. The results demonstrated the effect of post-packaging pasteurization on the shelf life of fresh from frozen products. However, the products pasteurized at 95°C in the absence of steam showed microbiological parameters that were not appropriate for an extended shelf life of up to 60 days. On the contrary, the samples pasteurized at 98°C with steam saturation and counterpressure showed values compatible with an extended shelf life. The results of the chemical-physical analyses highlighted how recipe and packaging affect the chemical-physical and organoleptic parameters. In conclusion, this preliminary study confirmed the effectiveness of post-packaging pasteurization treatments aimed at extending the shelf life of the product, helping the food company to occupy market niches even very distant from the production sites.

Keywords: shelf life, REPFED’s product, extended durability, pasteurization

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1 Belonging without Believing: Life Narratives of Six Social Generations of Members of the Apostolic Society

Authors: Frederique A. Demeijer

Abstract:

This article addresses the religious beliefs of members of the Apostolic Society –a Dutch religious community wherein the oldest living members were raised with very different beliefs than those upheld today. Currently, the Apostolic Society is the largest liberal religious community of the Netherlands, consisting of roughly 15,000 members. It is characterized by its close-knit community life and the importance of its apostle: the spiritual leader who writes a weekly letter around which the Sunday morning service is centered. The society sees itself as ‘religious-humanistic’, inspired by its Judeo-Christian roots without being dogmatic. Only a century earlier, the beliefs of the religious community revolved more strongly around the Bible, the apostle is a link to Christ. Also, the community believed in the return of the Lord, resonating with the millenarian roots of community in 1830. Thus, the oldest living members have experienced fundamental changes in beliefs and rituals, yet remained members. This article reveals how members experience(d) their religious beliefs and feelings of belonging to the community, how these may or may not have changed over time, and what role the Apostolic Society played in their lives. The article presents a qualitative research approach based on two main pillars. First, life narrative interviews were conducted, to work inductively and allow different interview topics to emerge. Second, it uses generational theory, in three ways: 1) to select respondents; 2) to guide the interview methodology –by being sensitive to differences in socio-historical context and events experienced during formative years of interviewees of different social generations, and 3) to analyze and contextualize the qualitative interview data. The data were gathered from 27 respondents, belonging to six social generations. All interviews were recorded, transcribed, coded, and analyzed, using the Atlas.ti software program. First, the elder generations talk about growing up with the Apostolic Society being absolutely central in their daily and spiritual lives. They spent most of their time with fellow members and dedicated their free time to Apostolic activities. The central beliefs of the Apostolic Society were clear and strongly upheld, and they experienced strong belonging. Although they now see the set of central beliefs to be more individually interpretable and are relieved to not have to spend all that time to Apostolic activities anymore, they still regularly attend services and speak longingly of the past with its strong belief and belonging. Second, the younger generations speak of growing up in a non-dogmatic, religious-humanist set of beliefs, but still with a very strong belonging to the religious community. They now go irregularly to services, and talk about belonging, but not as strong as the elderly generations do. Third, across the generations, members spend more time outside of the Apostolic Society than within. The way they speak about their religious beliefs is fluid and differs as much within generations as between: for example, there is no central view on what God is. It seems the experience of members of the Apostolic Society across different generations can now be characterized as belonging without believing.

Keywords: generational theory, individual religious experiences, life narrative history interviews, qualitative research design

Procedia PDF Downloads 109