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991.
Organizational Variables for Developing Collective Creativity in Business: A Case from an Italian Fashion Design Company 下载免费PDF全文
Stefano Cirella 《Creativity & Innovation Management》2016,25(3):331-343
The goal of this article is to propose a theoretical framework for collective creativity within an organizational design perspective and to help clarify this concept and how collective creativity can be purposefully managed. In particular, this study identifies relevant organizational variables for enhancing collective creativity and examines the relationship between collective creativity and organizational performance. The research draws upon a survey developed in the context of an in‐depth collaborative research study with an Italian fashion design company. As the theory on collective creativity is quite dispersed, the first part of the article attempts to define collective creativity and integrate different theoretical perspectives. Then, method and empirical findings are described. In the last part, the discussion illustrates why it is important for researchers and practitioners to be aware of the concept of collective creativity and its purposeful management. 相似文献
992.
Elson Agastra Claude Dedeban Giacomo Guarnieri Stefano Maddio Giuseppe Pelosi Christian Pichot Stefano Selleri 《国际射频与微波计算机辅助工程杂志》2011,21(5):551-559
In this article, an algorithm able to deal at the same time with wire frame and surface patch models for the method of moments in time domain is presented. After a unified theory combining both models, attention is focused on stability dependence issues on the time basis function chosen and on other algorithm parameters. An accurate analysis of time interpolation functions and of their time filtering properties is provided. © 2011 Wiley Periodicals, Inc. Int J RF and Microwave CAE, 2011. 相似文献
993.
Bernhard A. Schrefler Francesco Pesavento Lorenzo Sanavia Giuseppe Sciume Stefano Secchi Luciano Simoni 《Frontiers of Architecture and Civil Engineering in China》2011,5(1):41-52
Many problems are linked with the long-term behavior of both earthdams and concrete dams. They range from hydraulic fracturing
to alkali-silica reaction (ASR) and to repair work in concrete dams, from seismic behavior to secondary consolidation in earthdams.
A common framework for the simulation of such systems is shown, based on the mechanics of multiphase porous media. The general
model is particularized to specific situations and several examples are shown. 相似文献
994.
We investigate if while experiencing an intensely negative industry-specific shock, skilled entrepreneurs may decide to leave the firm they founded, whereas founders who are less endowed with human capital may decide to continue their activity. Developing a stylised theoretical framework of the issue intended to derive the necessary and sufficient conditions for the emergence of this phenomenon, this study explores its occurrence in Italy during the ICT industry crisis from early 2000–2003 by analysing the individual stay/leave decision of a sample of 201 founders of 79 start-ups operating in the ICT services market. 相似文献
995.
996.
Alessandra Colombo Andrea Schievano Stefano P. Trasatti Raffaele Morrone Nicola DAntona Pierangela Cristiani 《International Journal of Hydrogen Energy》2017,42(3):1841-1852
A microbial fuel cell (MFC) is an anaerobic bioreactor where soluble metabolites liberated by hydrolysis and fermentation of macromolecules are simultaneously available for anode respiring bacteria (ARB). ARB can be influenced by chemical imbalances in the liquid phase of the bioreactor. The objective of the work was to explore the trend of electric signals generated by MFCs, in relation to anaerobic biodegradation of four different solid food-industry residual substrates. Four sets of membraneless single-chamber MFCs were operated in batch mode, with solid waste substrates characterized by a different base component: i) mixed kitchen waste (fibers), ii) whey from dairy industries (sugar), iii) fisheries residues previously processed to recover oils (proteins), iv) pulp waste from citrus juice production (acidic).All the tested MFCs were able to produce an electric output with different trends, depending on the principal component of the solid substrate. MFC potential varied as function of the COD and the feeding cycle, as well as of the substrate.The pH variability during the fermentative process significantly affected the electric output. Citrus (acidic) pulp fed MFCs started to operate only when the pH raised up 6.5. MFCs fed with mix kitchen wastes had a relatively stable electric signal; fish based waste caused spiking in the MFC signal and an averaging in the COD degradation trend. This phenomenon was attributed to a pH instability induced by proteins degradation forming ammonia.The fermentation process was strongly predominant with respect the electrochemical process in MFCs and the coulombic efficiency (CE) was low, ranging between 2 and 10%. This result call for a deeper exploration of harvesting power from solid wastes and pointed also to the possibility of using a MFC to monitor important parameters of fermentation processes in biotech production plants. 相似文献
997.
Stefano Colombo 《The Annals of Regional Science》2011,46(2):397-416
We ask whether the tendency of Hotelling duopolists to choose uniform pricing (discriminatory pricing) when the pricing policy
is chosen before (after) the location is robust to the case of imperfect or third-degree price discrimination. By using a
general framework encompassing both perfect and imperfect price discrimination for any degree of imperfectness, we show that
both firms choose uniform pricing when the pricing policy is chosen before the location for any degree of imperfectness of
price discrimination. When the pricing policy is chosen after the location and price discrimination is precise enough both
firms choose price discrimination; if price discrimination is highly imprecise, an equilibrium exists where both firms commit
not to price discriminate. 相似文献
998.
Raffaele Graziano Valentina Preziosi Giovanna Tomaiuolo Karl Braeckman Stefano Guido 《加拿大化工杂志》2020,98(9):2008-2015
Foam formation in porous media is a topic of growing scientific and industrial interest due to its range of applications, from daily life consumer products to oil recovery. Despite the work done so far on foams flowing through complex structures, such as rigid porous media, this subject still needs to be fully elucidated. An additional complexity to the problem arises when the porous medium is deformable, a situation which has only been faced, to our knowledge, from a modelling point of view. In this work, the investigation of foam formation in deformable porous media is carried out by using commercial sponges as a deformable porous media system, with special emphasis on the effect of confinement on foam bubble size distribution. Foam is formed by wetting the sponge with an aqueous surfactant solution and then squeezing the sponge either between two glass cover slides or between a plastic net and a cover slide. Our experimental data reveal that the latter system allows the formation of drier foams (ie, with lower liquid fraction, fL < 0.3), more similar to the ones obtained in dish-washing applications. Moreover, the effect of sponge type, in terms of material and microstructure, on final foam is presented. Our results are of potential interest for the optimization of foams in complex structures, such as in deformable porous media. 相似文献
999.
Elena Crespi Paolo Colbertaldo Giulio Guandalini Stefano Campanari 《International Journal of Hydrogen Energy》2021,46(26):13691-13708
The increasing penetration of intermittent renewable sources, fostering power sector decarbonization, calls for the adoption of energy storage systems as an essential mean to improve local electricity exploitation, reducing the impact of distributed power generation on the electric grid. This work compares the use of hydrogen-based Power-to-Power systems, battery systems and hybrid hydrogen-battery systems to supply a constant 1 MWel load with electricity locally generated by a photovoltaic plant. A techno-economic optimization model is set up that optimizes the size and annual operation of the system components (photovoltaic field, electrolyzer, hydrogen storage tanks, fuel cell and batteries) with the objective of minimizing the annual average cost of electricity, while guaranteeing an imposed share of local renewable self-generation. Results show that, with the present values of investment costs and grid electricity prices, the installation of an energy storage system is not economically attractive by itself, whereas the installation of PV panels is beneficial in terms of costs, so that the baseline optimal solution consists of a 4.2 MWp solar field capable to self-generate 33% of the load annually. For imposed shares of self-generation above 40%, decoupling generation and consumption becomes necessary. The use of batteries is slightly less expensive than the use of hydrogen storage systems up to a 92% self-generation rate. Above this threshold, seasonal storage becomes predominant and hybrid storage becomes cheaper than batteries. The sale of excess electricity is always important to support the plant economics, and a sale price reduction sensibly impacts the results. Hydrogen storage becomes more competitive when the need for medium and long terms energy shift increases, e.g. in case of having a cap on the available PV capacity. 相似文献
1000.
Elvezia Maria Paraboschi Giulia Cardamone Valeria Rimoldi Donato Gemmati Marta Spreafico Stefano Duga Giulia Soldà Rosanna Asselta 《International journal of molecular sciences》2015,16(10):23463-23481
Abnormalities in RNA metabolism and alternative splicing (AS) are emerging as important players in complex disease phenotypes. In particular, accumulating evidence suggests the existence of pathogenic links between multiple sclerosis (MS) and altered AS, including functional studies showing that an imbalance in alternatively-spliced isoforms may contribute to disease etiology. Here, we tested whether the altered expression of AS-related genes represents a MS-specific signature. A comprehensive comparative analysis of gene expression profiles of publicly-available microarray datasets (190 MS cases, 182 controls), followed by gene-ontology enrichment analysis, highlighted a significant enrichment for differentially-expressed genes involved in RNA metabolism/AS. In detail, a total of 17 genes were found to be differentially expressed in MS in multiple datasets, with CELF1 being dysregulated in five out of seven studies. We confirmed CELF1 downregulation in MS (p = 0.0015) by real-time RT-PCRs on RNA extracted from blood cells of 30 cases and 30 controls. As a proof of concept, we experimentally verified the unbalance in alternatively-spliced isoforms in MS of the NFAT5 gene, a putative CELF1 target. In conclusion, for the first time we provide evidence of a consistent dysregulation of splicing-related genes in MS and we discuss its possible implications in modulating specific AS events in MS susceptibility genes. 相似文献