116 research outputs found
Bicriteria food packaging process optimization in double-layered upright and diagonal multihead weighers
[EN] Double-layered multihead weighing machines contain twice the number of hoppers as present in a simple machine with the same number of heads, which enables additional objective optimization possibilities considering the increased number of combinations among hoppers. This research study deals with bicriteria optimization for double-layered upright and diagonal machines using brute force as the optimization criteria. One of the optimization objectives is related to the target weight; the target weight must be at least and as close as possible to the weight to pack. Furthermore, this study also aims to minimize the time for which a certain portion of a product remains in the hopper while waiting to be selected for package formation. This time is known as priority and is measured based on the number of iterations or the number of packages produced by the machine while the hopper waits to be discharged. For these purposes, Different strategies were tested for both machines, which simultaneously optimize the target weight and the priority of the hoppers, showing the reduction of the extraction of the process in addition to reducing the costs of excess product and its reprocessing.We express our gratitude for the support from Universidad Simon Bolivar, Colombia, and Universitat Politecnica de Valencia.Garcia-Jimenez, R.; García-Díaz, JC.; Pulido-Rojano, AD. (2023). Bicriteria food packaging process optimization in double-layered upright and diagonal multihead weighers. Journal of Computational and Applied Mathematics. 428:1-10. https://doi.org/10.1016/j.cam.2023.11516811042
Stereotactic MR-guided online adaptive radiation therapy (SMART) for ultracentral thorax malignancies: Results of a phase 1 trial
Estrategias de optimización Bi-Objetivo para el proceso de pesaje multicabezal
[EN] Multihead weighing processes are considered an important strategy in packaging companies. Multihead weighers are used for
dosing a wide range of products, from granules to large products. The packaging process consists of choosing a subset of
hoppers in the multihead weigher to form a product package. This paper proposes a set of filling strategies of hoppers to
reduce the variability in the weight of the produced packages. The strategies are evaluated through a bi-objective optimization
approach which aims to minimize the absolute difference between the target weight and the actual weight of the packages,
while trying to maximize the selection of those hoppers with more time in the packaging system. In the bi-objective approach,
the considered objectives are dynamically adjusted and managed in each packaging operation. In addition, the mathematical
model and the packing algorithm are developed and presented. The results of the process performance parameters are
obtained and analyzed to show the effectiveness of the proposed strategies. Also, conditions of minimum variability are
identified and those can be used by the packaging industry where multihead weighers are used.[ES] Los procesos de pesaje multicabezal son actualmente considerados una estrategia importante en empresas de envasado.
Maquinas pesadoras multicabezal son utilizadas para la dosificación de amplia gama de productos, desde granulados a
productos de gran tamaño. El proceso de envasado consiste en la selección de un subconjunto de tolvas en la pesadora
multicabezal para formar un paquete de producto. La presente investigación propone un conjunto de estrategias de llenado de
tolvas para reducir la variabilidad en el peso de los paquetes producidos. Las estrategias son evaluadas mediante un enfoque
de optimización bi-objeivo que busca minimizar la diferencia absoluta entre el peso objetivo y el peso real de los paquetes, al
tiempo que intenta maximizar la selección de aquellas tolvas con mayor tiempo en el sistema de envasado. En el enfoque biobjetivo, los objetivos considerados son dinámicamente ajustados y gestionados en cada operación de envasado. Además, el
modelo matemático que representa nuestro problema y el algoritmo de envasado son desarrollados y presentados. Los
resultados de los parámetros de rendimiento del proceso son obtenidos y analizados como una medida de la efectividad de las
estrategias propuestas. Asimismo, las condiciones de mínima variabilidad son identificadas para motivar su uso en la
industria de envasado de producto en donde se utilicen máquinas de pesaje multicabezal.Pulido-Rojano, AD.; García-Díaz, JC. (2019). Estrategias de optimización Bi-Objetivo para el proceso de pesaje multicabezal. Investigación Operacional. 40(3):362-373. http://hdl.handle.net/10251/157765S36237340
Contrast of a Quality Control Model for Sustainability in a Mexican Organization in Central Mexico
Often, the total quality has been instrumented before being weighted. The strategies even precede a diagnosis in Mexican organizations, but in an opposite sense, the present work set out to establish the reliability and validity of an instrument to measure the perception of total quality based on three indicators related to management. , production and transfer of knowledge. A nonperimental study was carried out with a non-probabilistic selection of 124 administrative staff and employees from an organization in central Mexico. From a structural model ⌠X2 = 123,24 (23df) p = 0,010; GFI = 0,990; CFI =,991; IFI = 0,993; RMSEA = 0,007⌡, it was found that management affects production (0,38) and this about the total perceived quality (0,35), although there are lines of research concerning empathy, commitment, entrepreneurship, satisfaction and happiness in relation to the implementation of continuous improvements to the quality of processes and products
Improving the processes of production through risk management and statistical tools
Los enfoques de prevención de riesgos en actividades, funciones o procesos se han convertido en
piezas fundamentales a la hora de minimizar la ocurrencia de eventos que son perjudiciales para las
compañías. Cada producto no conforme está estrechamente ligado con eventos no deseados relacionados
con uno o algunos de los factores que intervienen en el proceso. La identificación, análisis, evaluación,
tratamiento, comunicación y monitoreo de estos eventos no deseados garantizarán el incremento de la
calidad en los productos y la productividad en el proceso productivo. En este artículo, proponemos un
diseño metodológico para la prevención de riesgos en procesos productivos. La metodología propone
una forma novedosa de combinar el uso de herramientas estadísticas de calidad y la norma ISO 31000
de gestión de riesgos. La validación fue hecha sobre un proceso de envasado de productos lácteos. Las
conclusiones de esta investigación muestran que el diseño metodológico propuesto es suficientemente
flexible para ser adaptado a cualquier tipo de proceso de fabricación que se desea monitorear y mejorar.Risk prevention approaches on activities, functions or processes are fundamental elements to prevent
events that are harmful to companies. Each non-conforming product is related to undesirable events
associated with the factors intervened in the process. The identification, analysis, evaluation, treatment,
communication and monitoring of these unwanted events will help to increase the quality of the products
and productivity in the production process. In this paper, we proposed a methodological design for
the prevention of risks in production processes. The methodology proposes a novel way of combining
statistical quality tools and the ISO 31000 standard for risk management. The validation was performed
on a process of packaging of dairy products. The conclusions of this research show that the proposed
methodological design is sufficiently flexible to be adapted to any type of manufacturing process that is
desired to be monitored and improved
Two-and-a-half-year clinical experience with the world\u27s first magnetic resonance image guided radiation therapy system
Allergen Sensitization and Asthma Outcomes among World Trade Center Rescue and Recovery Workers
A large number of World Trade Center (WTC) rescue and recovery workers are affected by asthma. While physical and mental health comorbidities have been associated with poor asthma control in this population, the potential role of allergen sensitization is unknown. This study examined the association of indoor sensitization and exposure as a risk factor for increased asthma morbidity in WTC workers. We used data from a prospective cohort of 331 WTC workers with asthma. Sensitization to indoor allergens was assessed by measurement of antigen-specific serum immunoglobulin E (IgE) levels. We used validated tools to evaluate the exposure to indoor allergens. Asthma morbidity outcomes included level of control (Asthma Control Questionnaire, ACQ), quality of life (Asthma Quality of Life Questionnaire, AQLQ) and acute resource utilization. The prevalence of sensitization to cat, dog, mouse, dust mite, cockroach, and mold allergens were 33%, 21%, 17%, 40%, 17%, and 17%, respectively. Unadjusted and regression analyses showed no significant relationship between sensitization and increased asthma morbidity (p \u3e 0.05 for all comparisons), except for sensitization to Aspergillus Fumigatus, cat and mouse epithelium, which were associated with decreased morbidity
Tropheryma whipplei, the Whipple's disease bacillus, induces macrophage apoptosis through the extrinsic pathway
Tropheryma whipplei, the etiological agent of Whipple's disease, is an intracellular bacterium that infects macrophages. We previously showed that infection of macrophages results in M2 polarization associated with induction of apoptosis and interleukin (IL)-16 secretion. In patients with Whipple's disease, circulating levels of apoptotic markers and IL-16 are increased and correlate with the activity of the disease. To gain insight into the understanding of the pathophysiology of this rare disease, we examined the molecular pathways involved in T. whipplei-induced apoptosis of human macrophages. Our data showed that apoptosis induction depended on bacterial viability and inhibition of bacterial protein synthesis reduced the apoptotic program elicited by T. whipplei. Induction of apoptosis was also associated with a massive degradation of both pro- and anti-apoptotic mediators. Caspase-specific inhibition experiments revealed that initiator caspases 8 and 10 were required for apoptosis, in contrast to caspases 2 and 9, in spite of cytochrome-c release from mitochondria. Finally, the effector caspases 3 and 6 were mandatory for apoptosis induction. Collectively, these data suggest that T. whipplei induces apoptosis through the extrinsic pathway and that, beside M2 polarization of macrophages, apoptosis induction contributes to bacterial replication and represents a virulence trait of this intracellular pathogen
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