516 research outputs found

    Industry 4.0 and Lean Six Sigma Integration in Manufacturing: A Literature Review, an Integrated Framework and Proposed Research Perspectives

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    This paper explores the literature on lean management (LM), Six Sigma (SS), Industry 4.0 (I4.0) and their relationship. A systematic literature review (SLR) combined with bibliometric analysis was conducted to identify, select and evaluate articles and was supported by content analysis to classify papers into group discussed clusters. A total of 134 articles were retrieved from relevant databases and publisher engines between 2011 and June 2022. The analysis of these articles enabled us to identify the impact of Industry 4.0 technologies on Lean Six Sigma; the relationship between LM, SS and Industry 4.0 and the implications of their combination on operational excellence. The results show that while a majority of researchers consider Industry 4.0 to be a driver of LSS and a prerequisite for helping companies access the data and analytics needed, others find them to be complementary and synergistic. Similarly, various authors support the idea that LSS could be a facilitator of Industry 4.0. This study provides an overview of the main research streams in this field and its shortcomings and presents an LSS4.0 framework integrating lean six sigma and Industry 4 which will be of great value to academics and practitioners working in this area

    Analysis of factors influencing Circular-Lean-Six Sigma 4.0 implementation considering sustainability implications: An exploratory study

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    In this study, we develop a new paradigm, Circular Lean Six Sigma 4.0 (CLSS4.0) to promote manufacturing sustainability. This paper aims to provide a practical and holistic view of the drivers and barriers that can help companies design an integrated CLSS4.0 model. The paper is based on a qualitative exploratory study using multiple case studies within 12 Moroccan manufacturing firms conducted through semi-structured interviews with top executive managers. The results show that the drivers are related to expected operational and environmental performance, increasing customer requirements, gaining competitive advantage and market growth while barriers are related to insufficient tangible (finance, human and equipment) and intangible (skills and techniques) resources, data privacy, technical issues and management support. The proposed framework identifies the assessment of drivers and barriers and their attributes as a starting point for managers to lead the CLSS4.0 transformation, thereby contributing to its successful implementation. To the best of our knowledge, this study is among the very first studies to discuss the CLSS4.0 drivers and barriers. It could be useful to managers as a diagnostic tool to assess their ability to implement CLSS4.0 before investing in the initiative

    THE TRUNK ORIENTATION DURING SPRINT START ESTIMATED USING A SINGLE INERTIAL SENSOR

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    Sprint start and block acceleration are two very important phases which could determine the result of a sprint. Tellez & Doolittle (1984) showed that these two phases account for 64% of the total result for a 100m sprint. Sprinters have to move from a crouch to a standing position, trying to reach their maximal velocity as fast as possible. Many authors have delved into the biomechanical factors concerning both phases (Fortier et al., 2005; Harland & Steele, 1997; Schot & Knutzen, 1992). Trunk orientation is considered by coaches one of the key elements in moving from the crouch to the upright position, however only a few studies focused specifically on this parameter (Čoh et al., 1998; Čoh et al., 2006; Natta et al., 2006). Moreover, the experimental setups used in the latter studies are quite cumbersome and limited in terms of acquisition volume (motion capture systems, high-speed cameras or optical contact time meters), therefore, they are hardly usable during everyday training sessions. Wearable inertial measurement units (IMU), that embed 3D linear acceleration and angular rate sensors (accelerometers and gyroscopes), can be effectively used to perform in-field biomechanical analysis of sprint running, providing information useful for performance optimisation and injury prevention. In particular, IMUs provide an estimate of body segment rotations relative to an inertia system of reference with one axis oriented as the gravitational field. The aim of this pilot study is to validate the use of a single IMU to estimate the trunk orientation angle in the progression plane during a sprint start from the blocks

    Microtubule actin cross-linking factor 1, a novel target in glioblastoma

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    Genetic heterogeneity is recognized as a major contributing factor of glioblastoma resistance to clinical treatment modalities and consequently low overall survival rates. This genetic diversity results in variations in protein expression, both intratumorally and between individual glioblastoma patients. In this regard, the spectraplakin protein, microtubule actin cross-linking factor 1 (MACF1), was examined in glioblastoma. An expression analysis of MACF1 in various types of brain tumor tissue revealed that MACF1 was predominately present in grade III-IV astroctyomas and grade IV glioblastoma, but not in normal brain tissue, normal human astrocytes and lower grade brain tumors. Subsequent genetic inhibition experiments showed that suppression of MACF1 selectively inhibited glioblastoma cell proliferation and migration in cell lines established from patient derived xenograft mouse models and immortalized glioblastoma cell lines that were associated with downregulation of the Wnt-signaling mediators, Axin1 and β-catenin. Additionally, concomitant MACF1 silencing with the chemotherapeutic agent temozolomide (TMZ) used for the clinical treatment of glioblastomas cooperatively reduced the proliferative capacity of glioblastoma cells. In conclusion, the present study represents the first investigation on the functional role of MACF1 in tumor cell biology, as well as demonstrates its potential as a unique biomarker that can be targeted synergistically with TMZ as part of a combinatorial therapeutic approach for the treatment of genetically multifarious glioblastomas

    Spray-dried plasma promotes growth, modulates the activity of antioxidant defenses, and enhances the immune status of gilthead sea bream (Sparus aurata) fingerlings

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    Terrestrial animal byproduct meals, including nonruminant blood meal and blood products, represent the largest and largely untapped safe source of animal protein available within the international market for the aquafeed industry. Spray-dried blood and spray-dried plasma (SDP) proteins have long been recognized as high-quality feed ingredients for farmed animals. In this study, we evaluated the inclusion of SDP from porcine blood (SDPP) in growing diets for gilthead sea bream. Three isonitrogenous (CP = 51.2%) and isolipidic (fat = 12.4%) diets manufactured by cold extrusion (0.8 to 1.5 mm pellet size) were prepared by substituting high-quality fish meal with 0, 3, and 6% SDPP. The diets were tested for a period of 60 d at 22°C with 4 replicates each (400-L cylindroconical tanks, 150 fish per tank, and initial density = 0.5 kg/ m3). The SDPP inclusion in diets for gilthead sea bream fingerlings were evaluated in terms of growth performance, feed utilization, histological organization of the intestinal mucosa, activity of oxidative stress enzymes (catalase, glutathione S-transferase, glutathione peroxidase, and glutathione reductase) in the intestine, and nonspecific serum immune parameters (lysozyme and bactericidal activity). Results from this study indicated that dietary SDPP promoted fish growth in terms of BW and length; fish fed 3% SDPP were 10.5% heavier (P < 0.05) than those fed the control diet. Spray-dried plasma from porcine blood modulated the activity of the antioxidative defenses in the intestine (P < 0.05) and increased the density of goblet cells in the intestine (P < 0.05) and benefited the host by providing an effective immune barrier against gut pathogenic microbiota. The nonspecific serum immune response in fish fed diets with SDPP was greater (P < 0.05) than in fish fed the control diet. These results indicated that the inclusion of SDPP in gilthead sea bream feed could be beneficial for the fish by enhancing intestinal and serum innate immune function and the activity of antioxidative stress enzymes of the intestine and promoting growth performance.info:eu-repo/semantics/publishedVersio

    Synthesis and reactivity of new heterocyclic systems derived from 5-chloro-1H-indole-2,3-dione

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    In this article, we described the synthesis of various derivatives of 5-Chloroisatin by the action of halogenated mono channels, benzyl chloride and methyl iodide under the conditions of phase transfer catalysis (PTC), which are widely used as a starting material for the synthesis of heterocyclic compounds and as substrates for the synthesis of drugs. In order to multiply the family heterocyclic compound from 5-Chloro-1H-indole-2,3-dione using the N-alkylation reaction which is answered in the field of organic chemistry and on which several studies were performed. The various products were determined by 1H NMR, and 13C NMR spectroscopy with good yield

    SYNTHESIS OF NEW 5-BROMO-1H-INDOLE-2,3-DIONE DERIVATIVES BY 1,3-DIPOLAR CYCLOADDITION

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    To contribute to the development of the chemistry of 5-bromo-isatin, we have synthesized new heterocyclic systems, using alkylation reactions under conditions of phase transfer catalysis to be then subjected to cycloaddition reactions dipolar involving 1,3-dipoles. The structures of the various products obtained were determined by 1H NMR, 13C NMR spectroscopy

    A mathematical model for fibro-proliferative wound healing disorders

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    The normal process of dermal wound healing fails in some cases, due to fibro-proliferative disorders such as keloid and hypertrophic scars. These types of abnormal healing may be regarded as pathologically excessive responses to wounding in terms of fibroblastic cell profiles and their inflammatory growth-factor mediators. Biologically, these conditions are poorly understood and current medical treatments are thus unreliable. In this paper, the authors apply an existing deterministic mathematical model for fibroplasia and wound contraction in adult mammalian dermis (Olsenet al., J. theor. Biol. 177, 113–128, 1995) to investigate key clinical problems concerning these healing disorders. A caricature model is proposed which retains the fundamental cellular and chemical components of the full model, in order to analyse the spatiotemporal dynamics of the initiation, progression, cessation and regression of fibro-contractive diseases in relation to normal healing. This model accounts for fibroblastic cell migration, proliferation and death and growth-factor diffusion, production by cells and tissue removal/decay. Explicit results are obtained in terms of the model processes and parameters. The rate of cellular production of the chemical is shown to be critical to the development of a stable pathological state. Further, cessation and/or regression of the disease depend on appropriate spatiotemporally varying forms for this production rate, which can be understood in terms of the bistability of the normal dermal and pathological steady states—a central property of the model, which is evident from stability and bifurcation analyses. The work predicts novel, biologically realistic and testable pathogenic and control mechanisms, the understanding of which will lead toward more effective strategies for clinical therapy of fibro-proliferative disorders

    Study of the inhibition of corrosion of mild steel in a 1M HCl solution by a new quaternary ammonium surfactant

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    The anticorrosive effect of surfactant, 12-(2,3-dioxoindolin-1-yl)-N,N,N-trimethyldodecanammonium bromide 3 on the corrosion of mild steel in 1M hydrochloric acid was assessed by gravimetric and electrochemical techniques (potentiodynamic polarization and electrochemical impedance spectroscopy). The results have shown that our synthesized surfactant is an excellent corrosion inhibitor for mild steel in 1 M HCl. Inhibitory efficacy of up to 95.9% was exhibited by surfactant 3 at a concentration of 1 mM after 6 h immersion at 298K. Based on the polarization curves, it is clear that the surfactant 3 can be considered as a mixed inhibitor with a predominantly anodic character. The inhibitory effectiveness increases with increasing concentration but decreases with increasing temperature. It was found that the adsorption of the inhibitor on the surface of the mild steel in 1M HCl followed the Langmuir adsorption isotherm. In this context, the main kinetic and thermodynamic parameters were determined and discussed
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