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Understanding food safety knowledge, attitude, and practices of consumers and vendors : an umbrella review
No full textFood safety is a global health issue, leading to foodborne illnesses and economic burdens worldwide. Ensuring high food safety standards is challenging because of the variations in knowledge, attitudes, and practices (KAP) among consumers and vendors. This umbrella review synthesizes reviews on consumer and vendor food safety KAP research from the last 20 years. Therefore, a comprehensive Web of Science, Scopus, and Google Scholar search was conducted. The eligibility of the review studies was assessed using the Population, Concept, and Context (PCC) framework, targeting systematic, scoping, and integrative reviews that examined one or more KAP components related to food safety. The quality assessment was accomplished using the ROBIS tool, with findings synthesized narratively. The review incorporates 20 review studies, covering 839 primary articles on food safety KAP across diverse contexts and regions. The quality assessment revealed a low risk of bias in most studies. Findings show that consumers are generally more knowledgeable and better adherent to food safety guidelines, driven by personal health motivations. However, vendors often exhibit inconsistent practices due to limited education and resources. Both groups exhibit positive attitudes but fail to apply safe practices consistently. The inadequacy of food safety KAP highlights the influence of regional, cultural, economic, and socio-demographic factors on practices. Future research should focus on underrepresented regions, improve methodologies, and explore vendor-consumer relationships. Emphasizing longitudinal studies, qualitative research and crossregional comparisons will enhance understanding of food safety KAP. Key recommendations include continuous training, community awareness, policy improvements, enhanced enforcement, increased investment in education, and public-private partnerships to strengthen food safety standards and safeguard public health.Food safety is a global health issue, leading to foodborne illnesses and economic burdens worldwide. Ensuring high food safety standards is challenging because of the variations in knowledge, attitudes, and practices (KAP) among consumers and vendors. This umbrella review synthesizes reviews on consumer and vendor food safety KAP research from the last 20 years. Therefore, a comprehensive Web of Science, Scopus, and Google Scholar search was conducted. The eligibility of the review studies was assessed using the Population, Concept, and Context (PCC) framework, targeting systematic, scoping, and integrative reviews that examined one or more KAP components related to food safety. The quality assessment was accomplished using the ROBIS tool, with findings synthesized narratively. The review incorporates 20 review studies, covering 839 primary articles on food safety KAP across diverse contexts and regions. The quality assessment revealed a low risk of bias in most studies. Findings show that consumers are generally more knowledgeable and better adherent to food safety guidelines, driven by personal health motivations. However, vendors often exhibit inconsistent practices due to limited education and resources. Both groups exhibit positive attitudes but fail to apply safe practices consistently. The inadequacy of food safety KAP highlights the influence of regional, cultural, economic, and socio-demographic factors on practices. Future research should focus on underrepresented regions, improve methodologies, and explore vendor-consumer relationships. Emphasizing longitudinal studies, qualitative research and crossregional comparisons will enhance understanding of food safety KAP. Key recommendations include continuous training, community awareness, policy improvements, enhanced enforcement, increased investment in education, and public-private partnerships to strengthen food safety standards and safeguard public health.A
Speckle tracking echocardiography in twin pregnancies and the role of global longitudinal strain and peak systolic strain : a systematic review and meta-analysis
No full textIntroduction: Twin pregnancies are associated with an increased risk of perinatal morbidity and mortality. Pregnancy complications related to twins, such as fetal growth restriction, and twin-to-twin transfusion syndrome (TTTS), are associated with hemodynamic changes in the fetal heart. Two-dimensional speckle tracking echocardiography (2D STE) is a tool to evaluate fetal cardiac function. This paper aims to review the literature regarding global longitudinal strain (rate) and peak systolic strain (rate) assessed with 2D STE in twin pregnancies. Feasibility, frame rate, and angle of the fetal heart at the time of measurement were selected as secondary outcomes. Methods: The databases Medline, Embase, Scopus, and Web of Science were searched. Results: Seven articles met the inclusion criteria and selected all monochorionic diamniotic (MCDA) twins with TTTS as the study population. The global longitudinal strain in the right and left ventricle and the peak systolic strain in the right ventricle of the recipient MCDA twin are significantly decreased compared to the donor MCDA twin. 2D STE assessment was shown feasible and reproducible in MCDA pregnancies. Large heterogeneity in technical characteristics between the articles induces inconsistent results. Conclusion: Although feasible, the knowledge of 2D STE is very limited in twin pregnancy. Prospective studies are needed to evaluate the 2D STE assessment in uncomplicated twin pregnancies considering its possible additive value in the diagnostics of pregnancy-related pathologies.Introduction: Twin pregnancies are associated with an increased risk of perinatal morbidity and mortality. Pregnancy complications related to twins, such as fetal growth restriction, and twin-to-twin transfusion syndrome (TTTS), are associated with hemodynamic changes in the fetal heart. Two-dimensional speckle tracking echocardiography (2D STE) is a tool to evaluate fetal cardiac function. This paper aims to review the literature regarding global longitudinal strain (rate) and peak systolic strain (rate) assessed with 2D STE in twin pregnancies. Feasibility, frame rate, and angle of the fetal heart at the time of measurement were selected as secondary outcomes. Methods: The databases Medline, Embase, Scopus, and Web of Science were searched. Results: Seven articles met the inclusion criteria and selected all monochorionic diamniotic (MCDA) twins with TTTS as the study population. The global longitudinal strain in the right and left ventricle and the peak systolic strain in the right ventricle of the recipient MCDA twin are significantly decreased compared to the donor MCDA twin. 2D STE assessment was shown feasible and reproducible in MCDA pregnancies. Large heterogeneity in technical characteristics between the articles induces inconsistent results. Conclusion: Although feasible, the knowledge of 2D STE is very limited in twin pregnancy. Prospective studies are needed to evaluate the 2D STE assessment in uncomplicated twin pregnancies considering its possible additive value in the diagnostics of pregnancy-related pathologies.A
Susceptibility of perivenous macrophages to PRRSV and ASFV and search for PRRSV/ASFV entry mediators by the use of monoclonal antibodies
No full textThe global swine industry suffers from significant economic losses due to porcine reproductive and respiratory syndrome virus (PRRSV) and African swine fever virus (ASFV) outbreaks. PRRSV, a positive-strand RNA virus, leads to reproductive failure in sows and respiratory problems across all age groups. ASFV, a double-stranded DNA virus, causes severe disease marked by high fever and hemorrhages, with mortality rates reaching up to 100%. Both PRRSV and ASFV exhibit a tropism for porcine macrophages, relying on specific entry mediators. This cell tropism is determined by the specific receptors expressed on susceptible cells, and the distribution of these susceptible cells helps in explaining the pathogenesis of each virus. A more comprehensive understanding of the interaction between viruses and susceptible cells, including the identification of these cells and the receptors essential for viral entry, may contribute to the development of antiviral drugs and more effective vaccines, as well as a more thorough understanding of the pathogenesis. In this thesis, we developed a novel in vitro vein explant model with which we identified a new macrophage subset, the perivenous macrophage, and analyzed its susceptibility to PRRSV and ASFV. In addition, we identified three new monoclonal antibodies (mAbs) which effectively block PRRSV and ASFV infections and that specifically recognize the macrophage proteins Siglec1, ANXA1 and MYH9.Public defense: 2025-02-24The global swine industry suffers from significant economic losses due to porcine reproductive and respiratory syndrome virus (PRRSV) and African swine fever virus (ASFV) outbreaks. PRRSV, a positive-strand RNA virus, leads to reproductive failure in sows and respiratory problems across all age groups. ASFV, a double-stranded DNA virus, causes severe disease marked by high fever and hemorrhages, with mortality rates reaching up to 100%. Both PRRSV and ASFV exhibit a tropism for porcine macrophages, relying on specific entry mediators. This cell tropism is determined by the specific receptors expressed on susceptible cells, and the distribution of these susceptible cells helps in explaining the pathogenesis of each virus. A more comprehensive understanding of the interaction between viruses and susceptible cells, including the identification of these cells and the receptors essential for viral entry, may contribute to the development of antiviral drugs and more effective vaccines, as well as a more thorough understanding of the pathogenesis. In this thesis, we developed a novel in vitro vein explant model with which we identified a new macrophage subset, the perivenous macrophage, and analyzed its susceptibility to PRRSV and ASFV. In addition, we identified three new monoclonal antibodies (mAbs) which effectively block PRRSV and ASFV infections and that specifically recognize the macrophage proteins Siglec1, ANXA1 and MYH9.D
Strategic honey bee hive placement improves honey bee visitation but not pollination in northern highbush blueberry
No full textCommercial blueberry Vaccinium spp. (Ericales: Ericaceae) production relies on insect-mediated pollination. Pollination is mostly provided by rented honey bees, Apis mellifera L. (Hymenoptera: Apidae), but blueberry cropyields can be limited dueto pollination deficits.Various hive placementstrategies have been recommended to mitigate pollination shortfalls, butthe effect of hive placement has received limited formal investigation.This study explores the effects of clumped and dispersed hive placement strategies on honey bee visitation and pollination outcomes in Bluecrop and Duke fields over 2 years (2021 and 2022) within 2 economically important regions of production in the United States-the Midwest (Michigan) and Pacific Northwest (Oregon and Washington). Clumping hives consistently increased honey bee visitation rate but did not result in higher fruit set, fruit weight, or seed count. Increases in honey bee visitation through clumping could perhaps improve pollination outcomes in more pollination-limited blueberry cultivars and other pollination-dependent crops. Clumping hives is substantially more efficient and cost-effective for beekeepers due to fewer drop locations and could lead to cost savings for both beekeepers and blueberry growers without growers sacrificing pollination levels and crop yields.Commercial blueberry Vaccinium spp. (Ericales: Ericaceae) production relies on insect-mediated pollination. Pollination is mostly provided by rented honey bees, Apis mellifera L. (Hymenoptera: Apidae), but blueberry cropyields can be limited dueto pollination deficits.Various hive placementstrategies have been recommended to mitigate pollination shortfalls, butthe effect of hive placement has received limited formal investigation.This study explores the effects of clumped and dispersed hive placement strategies on honey bee visitation and pollination outcomes in Bluecrop and Duke fields over 2 years (2021 and 2022) within 2 economically important regions of production in the United States-the Midwest (Michigan) and Pacific Northwest (Oregon and Washington). Clumping hives consistently increased honey bee visitation rate but did not result in higher fruit set, fruit weight, or seed count. Increases in honey bee visitation through clumping could perhaps improve pollination outcomes in more pollination-limited blueberry cultivars and other pollination-dependent crops. Clumping hives is substantially more efficient and cost-effective for beekeepers due to fewer drop locations and could lead to cost savings for both beekeepers and blueberry growers without growers sacrificing pollination levels and crop yields.A
Urban Workers' Assembly Halls since 1890: the Architectural Heritage and Social Memory of People’s Houses.
No full textAt the end of the nineteenth century, European cities witnessed the emergence of a new type of building: the workers' assembly hall. These so-called 'people's houses' not only provided the labour movement with spaces for political, social and cultural events, but they also symbolised the growing power of the labour movement.This presentation will discuss an ongoing research project on the history of people’s houses in Brussels, Paris, Vienna and Leipzig. Taking a ‘biographical’ approach of buildings, the research focuses on different stages in the life of a people’s house: its founding and the interactions with the political context, its architectural features and embeddedness in the urban landscape, the various uses of the people’s house and its symbolic significance for the labour movement, and finally its current role as a site of memory. Drawing on a wide range of archival sources – from police reports to postcards – and combining approaches from social, cultural and architectural history, this research seeks to provide a new understanding of people’s houses as a transnational phenomenon.At the end of the nineteenth century, European cities witnessed the emergence of a new type of building: the workers' assembly hall. These so-called 'people's houses' not only provided the labour movement with spaces for political, social and cultural events, but they also symbolised the growing power of the labour movement.This presentation will discuss an ongoing research project on the history of people’s houses in Brussels, Paris, Vienna and Leipzig. Taking a ‘biographical’ approach of buildings, the research focuses on different stages in the life of a people’s house: its founding and the interactions with the political context, its architectural features and embeddedness in the urban landscape, the various uses of the people’s house and its symbolic significance for the labour movement, and finally its current role as a site of memory. Drawing on a wide range of archival sources – from police reports to postcards – and combining approaches from social, cultural and architectural history, this research seeks to provide a new understanding of people’s houses as a transnational phenomenon.
Spectral Doppler of aortic and carotid blood flow in horses with aortic valve regurgitation
No full textA
Genetic counseling in veterinary medicine : towards an evidence-based definition for the small animal practice
No full textBackgroundIn human medicine, questions regarding heritable disorders are dealt with by clinical geneticists and genetic counselors and both the field, their roles and the tools they use are well-defined. Even though the prevalence of diseases is far higher and scientific literature agrees on expectations towards an increased importance, this does not seem to be the case in veterinary medicine. While we hypothesize that there will be an overlap, some characteristics uniquely linked to veterinary medicine might not be covered.MethodsTo investigate this in-depth and in an attempt to define the field, we compared the internationally accepted definitions and its subparts on genetic counseling in human medicine with what is found in veterinary literature and what was seen in cats and dogs presented at our dedicated small animals clinical genetics/genetic counseling clinic. The results were used in a stepwise analysis that lead to a set of three potential definitions (i.e. on what genetic counseling is, who provides it and which tools are used) that fullfill four criteria (i.e. definitions have to be clear/self-explanatory, minimally sufficient, complete and valid).ResultsThe short version of the definition of genetic counseling in veterinary medicine is: "Genetic counseling is the process of helping animal owners and breeders understand - and adapt to - the medical, psychological, familial implications of genetic contributions to disease." Genetic counseling in small animal practice is currently provided by veterinarians and the tools that are used, can be divided in five categories. The signalment of the patients revealed that both cats (30%) and dogs (70%) and various breeds, the two sexes (37% males, 63% females) and all age categories (puppy/kitten-senior) were represented. Furthermore, 73% of the patients were referred by or needed to be referred to other disciplines.ConclusionThese definitions are derived from human and veterinary literature, and an evaluation based on patient data has demonstrated that these definitions meet all the criteria of a correct definition (i.e. clear, minimally sufficient, complete and valid). With these definitions and case descriptions, our aim is to contribute to the formal foundation of genetic counseling in veterinary medicine.BackgroundIn human medicine, questions regarding heritable disorders are dealt with by clinical geneticists and genetic counselors and both the field, their roles and the tools they use are well-defined. Even though the prevalence of diseases is far higher and scientific literature agrees on expectations towards an increased importance, this does not seem to be the case in veterinary medicine. While we hypothesize that there will be an overlap, some characteristics uniquely linked to veterinary medicine might not be covered.MethodsTo investigate this in-depth and in an attempt to define the field, we compared the internationally accepted definitions and its subparts on genetic counseling in human medicine with what is found in veterinary literature and what was seen in cats and dogs presented at our dedicated small animals clinical genetics/genetic counseling clinic. The results were used in a stepwise analysis that lead to a set of three potential definitions (i.e. on what genetic counseling is, who provides it and which tools are used) that fullfill four criteria (i.e. definitions have to be clear/self-explanatory, minimally sufficient, complete and valid).ResultsThe short version of the definition of genetic counseling in veterinary medicine is: "Genetic counseling is the process of helping animal owners and breeders understand - and adapt to - the medical, psychological, familial implications of genetic contributions to disease." Genetic counseling in small animal practice is currently provided by veterinarians and the tools that are used, can be divided in five categories. The signalment of the patients revealed that both cats (30%) and dogs (70%) and various breeds, the two sexes (37% males, 63% females) and all age categories (puppy/kitten-senior) were represented. Furthermore, 73% of the patients were referred by or needed to be referred to other disciplines.ConclusionThese definitions are derived from human and veterinary literature, and an evaluation based on patient data has demonstrated that these definitions meet all the criteria of a correct definition (i.e. clear, minimally sufficient, complete and valid). With these definitions and case descriptions, our aim is to contribute to the formal foundation of genetic counseling in veterinary medicine.A
Rejection of an emerging small neutral organic micropollutant by in-situ nanofiltration membrane modification for water treatment
No full textNanofiltration (NF) membranes are recognized for their potential in removing organic micropollutants (OMPs). However, the limited efficiency of commercial NF membranes in removing small and neutral emerging OMPs has impeded its wide use. This study explores the effectiveness of in-situ modification of commercial NF270 membranes using two monomers for the removal of 1H-benzotriazole (BTA). For the first time, this work investigates the physicochemical properties of commercial NF270 membranes grafted with these two monomers, 3-(trimethoxysilyl)propyl methacrylate and 2-(diethylamino)ethyl methacrylate, using different surface characterization techniques. The study also evaluates the performance of both unmodified and modified membranes in the rejection of BTA and compares the results with state-of-the-art monomers. The 2-(diethylamino)ethyl methacrylate-grafted membranes show a modest enhancement of 12 % in BTA rejection. In contrast, the 3-(trimethoxysilyl)propyl methacrylate-modified membranes exhibit a remarkable 107 % improvement in BTA rejection compared to the virgin NF270 membrane, achieving the highest increase in OMP removal among current state-of-the-art monomer-modified membranes reported in previous research. This approach effectively removes BTA primarily through the mechanisms of size exclusion and hydrophobic interactions. This research presents a comprehensive strategy for surface modification of NF membranes, offering potential improvements in the rejection of small and neutral OMPs for water treatment.Nanofiltration (NF) membranes are recognized for their potential in removing organic micropollutants (OMPs). However, the limited efficiency of commercial NF membranes in removing small and neutral emerging OMPs has impeded its wide use. This study explores the effectiveness of in-situ modification of commercial NF270 membranes using two monomers for the removal of 1H-benzotriazole (BTA). For the first time, this work investigates the physicochemical properties of commercial NF270 membranes grafted with these two monomers, 3-(trimethoxysilyl)propyl methacrylate and 2-(diethylamino)ethyl methacrylate, using different surface characterization techniques. The study also evaluates the performance of both unmodified and modified membranes in the rejection of BTA and compares the results with state-of-the-art monomers. The 2-(diethylamino)ethyl methacrylate-grafted membranes show a modest enhancement of 12 % in BTA rejection. In contrast, the 3-(trimethoxysilyl)propyl methacrylate-modified membranes exhibit a remarkable 107 % improvement in BTA rejection compared to the virgin NF270 membrane, achieving the highest increase in OMP removal among current state-of-the-art monomer-modified membranes reported in previous research. This approach effectively removes BTA primarily through the mechanisms of size exclusion and hydrophobic interactions. This research presents a comprehensive strategy for surface modification of NF membranes, offering potential improvements in the rejection of small and neutral OMPs for water treatment.A
Excelleren in humane wetenschappen : de authentieke leraren
No full textExcelleren in Humane Wetenschappen: de authentieke leraren In een tijd waarin onderwijs vaak negatief belicht wordt, onderzochten we succesvolle onderwijspraktijken binnen de Humane Wetenschappen. Door middel van casussen bieden we inzichten in deze door de Vlaamse onderwijsinspectie positief beoordeelde praktijken, evenals in de didactische aanpakken van deze leraren die bijdragen aan het excelleren van hun klaspraktijken. In de afgelopen jaren wordt onderwijs vaak negatief belicht door de voortdurende aandacht voor de uitdagingen en tekortkomingen binnen het systeem. Toch zijn er tal van voorbeelden van uitmuntende onderwijspraktijken, waaronder ook in Humane Wetenschappen. Deze studie richt zich op succesvolle onderwijspraktijken in Humane Wetenschappen binnen het Vlaams secundair onderwijs, die positief zijn beoordeeld door de Vlaamse onderwijsinspectie. Ondanks de negatieve perceptie rond onderwijs wordt er weinig onderzoek gedaan naar de didactische strategieën die leraren Humane Wetenschappen in staat stellen om excellent te presteren en positieve evaluaties te ontvangen. Deze studie heeft als doel om deze succesvolle onderwijspraktijken te identificeren, en te onderzoeken welke concrete handelingen en keuzes bijdragen aan de onderwijskwaliteit in Humane Wetenschappen. Om deze vraag te beantwoorden, werd gebruik gemaakt van casestudieonderzoek (Yin, 2009). Acht secundaire scholen werden geselecteerd op basis van openbaar toegankelijke inspectieverslagen. In november 2023 werden vijf van deze scholen bezocht, waarbij in elke school semi-gestructureerde interviews werden afgenomen met de directeur en minstens twee leraren van de vakgroep Humane Wetenschappen. Daarnaast werd in elke school een focusgroepgesprek georganiseerd met ongeveer 10 leerlingen leerlingen uit de derde graad, en werd een lesobservatie uitgevoerd in een vak binnen de Humane Wetenschappen. De verzamelde gegevens werden verticaal geanalyseerd per school aan de hand van een vast format, gebaseerd op de ontwikkelingsschalen van de Vlaamse onderwijsinspectie. Vervolgens werd een horizontale analyse (Eisenhardt, 1989) uitgevoerd om overeenkomsten en verschillen tussen de scholen te identificeren. Uit deze analyses kwamen meerdere belangrijke bevindingen naar voren. Ten eerste bleek dat de meeste scholen een goed opgebouwde leerlijn voor Humane Wetenschappen volgen, waarbij leraren er vaak in slagen de vastgestelde leerdoelen te overstijgen door bijvoorbeeld onderzoeksvaardigheden te integreren. Opmerkelijk is dat de meeste leraren, geen handboek volgen maar eigen lesmateriaal ontwikkelen. Daarnaast leggen deze leraren een sterke focus op de verbinding tussen de leerinhouden en het dagelijks leven van de leerlingen, wat zorgt voor een hoge betrokkenheid. Verder blijkt dat leraren die uitblinken in de Humane Wetenschappen veel waarde hechten aan een positieve relatie met hun leerlingen, gekenmerkt door openheid, authenticiteit en wederzijds respect.Excelleren in Humane Wetenschappen: de authentieke leraren In een tijd waarin onderwijs vaak negatief belicht wordt, onderzochten we succesvolle onderwijspraktijken binnen de Humane Wetenschappen. Door middel van casussen bieden we inzichten in deze door de Vlaamse onderwijsinspectie positief beoordeelde praktijken, evenals in de didactische aanpakken van deze leraren die bijdragen aan het excelleren van hun klaspraktijken. In de afgelopen jaren wordt onderwijs vaak negatief belicht door de voortdurende aandacht voor de uitdagingen en tekortkomingen binnen het systeem. Toch zijn er tal van voorbeelden van uitmuntende onderwijspraktijken, waaronder ook in Humane Wetenschappen. Deze studie richt zich op succesvolle onderwijspraktijken in Humane Wetenschappen binnen het Vlaams secundair onderwijs, die positief zijn beoordeeld door de Vlaamse onderwijsinspectie. Ondanks de negatieve perceptie rond onderwijs wordt er weinig onderzoek gedaan naar de didactische strategieën die leraren Humane Wetenschappen in staat stellen om excellent te presteren en positieve evaluaties te ontvangen. Deze studie heeft als doel om deze succesvolle onderwijspraktijken te identificeren, en te onderzoeken welke concrete handelingen en keuzes bijdragen aan de onderwijskwaliteit in Humane Wetenschappen. Om deze vraag te beantwoorden, werd gebruik gemaakt van casestudieonderzoek (Yin, 2009). Acht secundaire scholen werden geselecteerd op basis van openbaar toegankelijke inspectieverslagen. In november 2023 werden vijf van deze scholen bezocht, waarbij in elke school semi-gestructureerde interviews werden afgenomen met de directeur en minstens twee leraren van de vakgroep Humane Wetenschappen. Daarnaast werd in elke school een focusgroepgesprek georganiseerd met ongeveer 10 leerlingen leerlingen uit de derde graad, en werd een lesobservatie uitgevoerd in een vak binnen de Humane Wetenschappen. De verzamelde gegevens werden verticaal geanalyseerd per school aan de hand van een vast format, gebaseerd op de ontwikkelingsschalen van de Vlaamse onderwijsinspectie. Vervolgens werd een horizontale analyse (Eisenhardt, 1989) uitgevoerd om overeenkomsten en verschillen tussen de scholen te identificeren. Uit deze analyses kwamen meerdere belangrijke bevindingen naar voren. Ten eerste bleek dat de meeste scholen een goed opgebouwde leerlijn voor Humane Wetenschappen volgen, waarbij leraren er vaak in slagen de vastgestelde leerdoelen te overstijgen door bijvoorbeeld onderzoeksvaardigheden te integreren. Opmerkelijk is dat de meeste leraren, geen handboek volgen maar eigen lesmateriaal ontwikkelen. Daarnaast leggen deze leraren een sterke focus op de verbinding tussen de leerinhouden en het dagelijks leven van de leerlingen, wat zorgt voor een hoge betrokkenheid. Verder blijkt dat leraren die uitblinken in de Humane Wetenschappen veel waarde hechten aan een positieve relatie met hun leerlingen, gekenmerkt door openheid, authenticiteit en wederzijds respect.C
A deep neural network approach to predict dimensional accuracy of thin-walled tubes in backward flow forming plasticity process
No full textFlow forming is a cold forming method that significantly enhances the mechanical properties of the workpiece. The main goal of this study is to perform a new prediction method for flow formed part dimensional accuracy based on Deep Neural Network (DNN) and Finite Element Analysis (FEA). The DIN 1.7220 steel is generated in this work because it is used in the automotive and aerospace industries due to its high fatigue strength and abrasion resistance. The selection of flow forming parameters, including the feed rate and spindle speed, is essential to guarantee that the dimensional specifications of the component design are fulfilled. Potential defects, such as material build-up, bulge, and diametrical growth, are predicted using FEA. This research addresses the limited literature on flow-forming operations, particularly the absence of studies integrating DNN with the flowforming process to compare dimensional accuracy against FEA. This methodological innovation aims at leveraging Machine Learning (ML) to enhance precision in predicting outcomes based on critical parameters such as feed rate and mandrel speed, directly influencing wall thickness variation and mean inner diameter of the parts in a fixed reduction ratio and roller dimensions. Although variable hidden layers and neurons are generated, the most accurate results are found in three hidden layers with eight neurons compared to FEA outcomes. Rectified Linear Unit (ReLU) activation function is used in the model. Based on this DNN model configuration, the overall error in wall thickness and mean inner diameter is less than 0.01 % across all five groups. The Root Mean Square (RMS) error is used to show the differences between wall thickness and mean inner diameters predicted by the DNN model and the actual values. The minimum wall thickness RMS error among all the groups is 0.013, and the lowest mean inner diameter is found to be 0.001. A comparative analysis demonstrates that the newly proposed DNN method can accurately predict the final dimensions of flow formed tubes with low computational costs. The predictive precision and reliability are significantly enhanced compared to the theoretical framework based on FEA results. The integration of DNN with FEA enhances dimensional predictions, offering high accurate results while reducing computation time.Flow forming is a cold forming method that significantly enhances the mechanical properties of the workpiece. The main goal of this study is to perform a new prediction method for flow formed part dimensional accuracy based on Deep Neural Network (DNN) and Finite Element Analysis (FEA). The DIN 1.7220 steel is generated in this work because it is used in the automotive and aerospace industries due to its high fatigue strength and abrasion resistance. The selection of flow forming parameters, including the feed rate and spindle speed, is essential to guarantee that the dimensional specifications of the component design are fulfilled. Potential defects, such as material build-up, bulge, and diametrical growth, are predicted using FEA. This research addresses the limited literature on flow-forming operations, particularly the absence of studies integrating DNN with the flowforming process to compare dimensional accuracy against FEA. This methodological innovation aims at leveraging Machine Learning (ML) to enhance precision in predicting outcomes based on critical parameters such as feed rate and mandrel speed, directly influencing wall thickness variation and mean inner diameter of the parts in a fixed reduction ratio and roller dimensions. Although variable hidden layers and neurons are generated, the most accurate results are found in three hidden layers with eight neurons compared to FEA outcomes. Rectified Linear Unit (ReLU) activation function is used in the model. Based on this DNN model configuration, the overall error in wall thickness and mean inner diameter is less than 0.01 % across all five groups. The Root Mean Square (RMS) error is used to show the differences between wall thickness and mean inner diameters predicted by the DNN model and the actual values. The minimum wall thickness RMS error among all the groups is 0.013, and the lowest mean inner diameter is found to be 0.001. A comparative analysis demonstrates that the newly proposed DNN method can accurately predict the final dimensions of flow formed tubes with low computational costs. The predictive precision and reliability are significantly enhanced compared to the theoretical framework based on FEA results. The integration of DNN with FEA enhances dimensional predictions, offering high accurate results while reducing computation time.A