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151.
Although many firms report large benefits from lean implementation, a lot of scepticism still remains regarding attainable results and the possibility to apply Lean approach outside high-volume manufacturing and stable context. In this work, combining field interviews with literature review, theoretical connections have been developed among Lean manufacturing techniques, operational responsiveness and company growth performances. A conceptual model has been proposed for investigating the network of influences among lean practices (supplier management, human resource management, just-in-time and total quality management practices), operational responsiveness (Product mix variety, Product innovation and Time effectiveness) and company growth performances in Italian companies. Using structural equation modelling, a second-order confirmatory factor analysis has been used to test the hypothesised relationships in the structural models. This study highlights that the operational responsiveness is only partially connected to a Lean strategy of a company. Indeed, the lean practices implementations are negatively influenced by product mix variety and innovation, while positively influenced by time effectiveness variables. Moreover, product mix variety and time effectiveness are the main characteristics of the operational responsiveness that positively influences company growth performances. So time effectiveness could be considered as a mediator between Lean best practices and firm growth. Moreover, no direct relationship has been found between lean bundles and firm’s performances. Lack of resources and mainly poor communication and managers’ commitment and support seem to be the main obstacles of lean implementation and success. 相似文献
152.
Michele Melchionna Paolo Fornasiero Maurizio Prato 《Advanced materials (Deerfield Beach, Fla.)》2019,31(13)
One of the recent trends in electrocatalytic reactions involves the oxygen reduction reaction (ORR), where a new paradigm has been shaped to exploit this reaction for the synthesis of hydrogen peroxide (H2O2). H2O2 is a very versatile chemical of high commercial value, prepared currently through poorly sustainable processes. The emergence of metal‐free carbon catalysts for the selective synthesis of H2O2 is expected to revolutionize ORR research, beckoning at the development of new industrial schemes. The complexities of the mechanism and the factors dominating the selectivity of the process have been unveiled through a combination of theoretical and experimental studies. 相似文献
153.
154.
Gaia Mosconi Matthias Korn Christian Reuter Peter Tolmie Maurizio Teli Volkmar Pipek 《Computer Supported Cooperative Work (CSCW)》2017,26(4-6):959-1003
In recent years, social media have increased the resources that individuals and organizations are able to mobilize for the development of socially innovative practices. In this article, we engage with a naturally occurring development in a Trentinian neighbourhood to examine the cooperative interactions amongst members of a local community. The first author and local residents of the neighbourhood participated in online discussions, decision making, and physical activities that led to material changes in the area. The interventions are motivated by and based on the concept of Social Street that combines online interactions in a closed Facebook group with face-to-face meetings seeking to practically engage the collective in accomplishing certain immediate or ongoing needs. Over the course of two years, we studied this local instantiation of Social Street in Trento, Italy by way of an action-oriented (digital) ethnography. Through this work, we demonstrate how urban neighbourhoods might benefit from hybrid forms of community engagement that are enacted through a constant back and forth between online and face-to-face interactions. We further argue that the infrastructuring of local urban collectives should follow strategies that pay attention to the multiple issues in urban neighbourhoods and people’s attachments to them. Overall, the paper reflects upon the challenges and configurations of participation that this form of community-work entails. 相似文献
155.
Physical properties of straw lignin-based polymer blends 总被引:1,自引:0,他引:1
Rachele Pucciariello Vincenzo Villani Carlo Bonini Maurizio D'Auria Teresa Vetere 《Polymer》2004,45(12):4159-4169
Lignin powder, obtained from an abundant and low cost source, straw, through a low environmental impact process, the steam explosion, is used for the preparation of blends with low-density polyethylene (LDPE), linear low-density polyethylene (LLDPE), high-density polyethylene (HDPE) and atactic polystyrene (PS).The obtained blends are processable through the conventional techniques used for thermoplastics; the modulus slightly increases for most lignin-polymer blends, while the tensile stress and elongation reduce. Moreover, lignin acts as a stabilzer against the UV radiation for PS, LDPE and LLDPE. 相似文献
156.
Maurizio?ServiliEmail author Roberto?Selvaggini Agnese?Taticchi Sonia?Esposto Gianfrancesco?Montedoro 《Journal of the American Oil Chemists' Society》2003,80(7):685-695
The time of exposure of olive pastes to air contact (TEOPAC) during malaxation was studied as a processing parameter that
could be used to control endogenous oxidoreductases, such as polyphenoloxidase, peroxidase, and lipoxygenase, which affect
virgin olive oil quality. Phenolic and volatile compounds were analyzed in the oils obtained using progressive TEOPAC at three
ripening stages of olives. Multivariate statistical analysis was applied to the raw data. The phenolic concentration of virgin
olive oil progressively decreased with increasing IEOPAC. On the contrary, a positive relationship was found with the concentration
of several volatile compounds responsible for virgin olive oil aroma. The effect of TEOPAC, however, was strictly related
to fruit ripening. 相似文献
157.
Sanità Di Toppi L Musetti R Vattuone Z Pawlik-Skowrońska B Fossati F Bertoli L Badiani M Favali MA 《Microscopy research and technique》2005,66(5):229-238
In this work, we tried to go deeper inside distribution and toxicity of cadmium (Cd) in the macrolichen Xanthoria parietina (L.) Th. Fr. Thalli of this species were treated with 0 (control), 4.5, 9, 18, or 36 muM Cd for 24 or 48 hours. Transmission electron microscopy, X-ray microanalysis, and electron energy loss spectroscopy were exploited to study distribution and ultrastructural effects of Cd in thalli; spectrophotometric techniques were utilized for measuring Cd effects on chlorophyll (Chl) content; light fluorescence microscopy was used to evaluate Chl autofluorescence. The highest Cd concentration caused ultrastructural alterations both in the mycobiont and in the photobiont, more severe in the latter, decreased total Chl content and progressively quenched Chl autofluorescence. Cell wall immobilization was observed in both bionts, and evidence pointing to a Cd-binding ability by the concentric bodies in the mycobiont was also obtained. Lower Cd concentrations led to slight or even no effects on thallus structures and on Chl content and autofluorescence. The results obtained suggest that: (1) among the two bionts, the algal partner appears to be more susceptible to Cd stress, probably because of the presence of delicate and sensitive components such as the chloroplast and photosynthetic pigments; (2) a concentration threshold exists for the occurrence of evident structural and functional damage in X. parietina thalli exposed to Cd. 相似文献
158.
The time–space distribution of eigen-stresses and residual deformations of a plane plate which reaches its final solid state through a given transition process of non-uniform cooling is described here by means of a simple visco-elastic rheological model.
The aging processes of the elastic and viscous properties are supposed to be temperature dependant in order to directly control the influence of the thermal history on the final stress and deformation conditions of the solid.
The model is able to reproduce qualitatively well the development of eigen-stresses in the spatially symmetrical cooling processes of tempering or toughening, as well as the formation of eigen-stresses and permanent bending in the spatially asymmetrical cooling processes of heat curving. 相似文献
159.
Dr. Riccardo Martini Dr. Francesca Esposito Dr. Angela Corona Dr. Roberto Ferrarese Dr. Elisa Rita Ceresola Dr. Laura Visconti Dr. Cristina Tintori Dr. Alessandro Barbieri Dr. Andrea Calcaterra Dr. Valentina Iovine Dr. Filippo Canducci Prof. Enzo Tramontano Prof. Maurizio Botta 《Chembiochem : a European journal of chemical biology》2017,18(4):374-377
160.