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641.
Silvia Cantarello Antonella Martini Anna Nosella 《Creativity & Innovation Management》2012,21(1):28-48
Innovation is one of the most critical means in supporting and improving the competitive position of the firm, in particular, and a firm's survival and growth depend greatly on its ability to balance the exploitation of existing knowledge with the exploration of new possibilities, by building ambidexterity capability. While different alternatives to realize the simultaneous reconciliation of exploration and exploitation at an operational level have been proposed, how organizations build ambidexterity capability is not fully understood. The aim of this paper is thus to explore how exploration and exploitation balancing can be achieved in practice. We decided to focus on the early phase of the process where firms search for new ideas with which to renew themselves. To this end, we analysed the search phase of a highly innovative technology‐based company by investigating structural design choices combined with the presence of specific roles and searching practices. The results show how the exploration and exploitation balancing act can actually be achieved and maintained through a multi‐level approach that integrates both the operational and the strategic levels. Our findings thus contribute to the organizational ambidexterity literature, by proposing a first interpretative model for dealing with ambidexterity in the search phase of the innovation process. 相似文献
642.
Gian Paolo Incremona Michele Cucuzzella Antonella Ferrara 《International journal of control》2016,89(9):1849-1867
ABSTRACTThis paper deals with the design of adaptive suboptimal second-order sliding mode (ASSOSM) control laws for grid-connected microgrids. Due to the presence of the inverter, of unpredicted load changes, of switching among different renewable energy sources, and of electrical parameters variations, the microgrid model is usually affected by uncertain terms which are bounded, but with unknown upper bounds. To theoretically frame the control problem, the class of second-order systems in Brunovsky canonical form, characterised by the presence of matched uncertain terms with unknown bounds, is first considered. Four adaptive strategies are designed, analysed and compared to select the most effective ones to be applied to the microgrid case study. In the first two strategies, the control amplitude is continuously adjusted, so as to arrive at dominating the effect of the uncertainty on the controlled system. When a suitable control amplitude is attained, the origin of the state space of the auxiliary system becomes attractive. In the other two strategies, a suitable blend between two components, one mainly working during the reaching phase, the other being the predominant one in a vicinity of the sliding manifold, is generated, so as to reduce the control amplitude in steady state. The microgrid system in a grid-connected operation mode, controlled via the selected ASSOSM control strategies, exhibits appreciable stability properties, as proved theoretically and shown in simulation. 相似文献
643.
Social Conduct,Learning and Innovation: An Abductive Study of the Dark Side of Agile Software Development 下载免费PDF全文
Maria Carmela Annosi Mats Magnusson Antonella Martini Francesco Paolo Appio 《Creativity & Innovation Management》2016,25(4):515-535
Agile methodologies have been adopted by an increasing number of organizations to improve their responsiveness. However, few studies have empirically analysed the effect of Agile on long‐term organizational goals such as learning and innovation. Using an abductive approach, this study examines the relationships between self‐regulated teams' social conduct and their resulting learning and innovation. Results indicate that the time pressure induced by the implementation of Agile impedes team engagement in learning and innovation activities. Time pressure is affected by a set of different control strategies, more specifically concertive, belief, diagnostic and boundary controls, and these need to be adequately addressed in order to minimize the potential dark side of Agile. 相似文献
644.
Iera Antonio Marano Salvatore Molinaro Antonella 《International Journal of Wireless Information Networks》1997,4(4):233-247
The management of multimedia teleservices inthird-generation mobile radio environments is achallenging task due to the multicomposite andmultirequirement nature of this kind of traffic.Following the choice of carrying multimedia information onmultiple bearers over the air interface of a wirelesspersonal communication system, and after the selectionof a TDMA-like multiple access protocol based on the bandwidth reservation, the system isrequired to provide for an interstream synchronizationamong components of the multimedia service. This paperpresents an architecture for guaranteeing that temporal relationships among components at thetransmitter side can be maintained, after crossing theair interface, at the receiver side, regardless ofdifferent bearers' delay constraints and delays sufferedin the buffer of the base station. The attentionis focused on a kind of roughsynchronization to be performed on the system MAC leveland refined by higher protocol layers. Static anddynamic priorities concepts are exploited to achieve the targetsynchronization degree among components. Simulationresults, carried out in a case of a video-audioconnection, confirm the effectiveness of the proposedmechanism. 相似文献
645.
Graziella L. Turdean Ionel Catalin Popescu Antonella Curulli Giuseppe Palleschi 《Electrochimica acta》2006,51(28):6435-6441
Iron(III) protoporphyrin IX (Fe(III)P), adsorbed either on single-walled carbon nanotubes (SWCNT) or on hydroxyl-functionalized SWCNT (SWCNT-OH), was incorporated within a Nafion matrix immobilized on the surface of a graphite electrode. From cyclic voltammetric measurements, performed under different experimental conditions (pH and potential scan rate), it was established that the Fe(III)P/Fe(II)P redox couple involves 1e−/1H+. The heterogeneous electron transfer process occurred faster when Fe(III)P was adsorbed on SWCNT-OH (11 s−1) than on SWCNT (4.9 s−1). Both the SWCNT-Fe(III)P- and SWCNT-OH-Fe(III)P-modified graphite electrodes exhibit electrocatalytic activity for H2O2 and nitrite reduction. The modified electrodes sensitivities were found varying in the following sequences: SSWCNT-OH-Fe(III)P = 2.45 mA/M ≈ SSWCNT-Fe(III)P = 2.95 mA/M > SFe(III)P = 1.34 mA/M for H2O2, and SSWCNT-Fe(III)P = 3.54 mA/M > SFe(III)P = 1.44 mA/M > SSWCNT-OH-Fe(III)P = 0.81 mA/M for NO2−. 相似文献
646.
Alessandra Soriente Ines Fasolino Maria Grazia Raucci Christian Demitri Marta Madaghiele Antonella Giuri Alessandro Sannino Luigi Ambrosio 《Journal of materials science. Materials in medicine》2018,29(5):62
The present work is focused on the design of a bioactive chitosan-based scaffold functionalized with organic and inorganic signals to provide the biochemical cues for promoting stem cell osteogenic commitment. The first approach is based on the use of a sequence of 20 amino acids corresponding to a 68–87 sequence in knuckle epitope of BMP-2 that was coupled covalently to the carboxyl group of chitosan scaffold. Meanwhile, the second approach is based on the biomimetic treatment, which allows the formation of hydroxyapatite nuclei on the scaffold surface. Both scaffolds bioactivated with organic and inorganic signals induce higher expression of an early marker of osteogenic differentiation (ALP) than the neat scaffolds after 3 days of cell culture. However, scaffolds decorated with BMP-mimicking peptide show higher values of ALP than the biomineralized one. Nevertheless, the biomineralized scaffolds showed better cellular behaviour than neat scaffolds, demonstrating the good effect of hydroxyapatite deposits on hMSC osteogenic differentiation. At long incubation time no significant difference among the biomineralized and BMP-activated scaffolds was observed. Furthermore, the highest level of Osteocalcin expression (OCN) was observed for scaffold with BMP2 mimic-peptide at day 21. The overall results showed that the presence of bioactive signals on the scaffold surface allows an osteoinductive effect on hMSC in a basal medium, making the modified chitosan scaffolds a promising candidate for bone tissue regeneration. 相似文献
647.
Cinzia Montemurro Antonella Pasqualone Rosanna Simeone Wilma Sabetta Antonio Blanco 《European Food Research and Technology》2008,226(6):1439-1444
Olive oil traceability becomes instrumental to ensure the consumer’s protection, particularly for extra virgin olive oil,
the quality of which is highly related to the cultivars employed. The aim of this investigation was to evaluate the possibility
of identifying the cultivar used to obtain the derived olive oil by the analysis of amplified fragment length polymorphism
(AFLP) markers. To this purpose, ten virgin olive oils were prepared in the laboratory from ten different very common Italian
cultivars and were then analysed using six AFLP primer combinations. The technique was optimised for fragmented DNA of oil
in order to enhance the intensity of the bands in the AFLP patterns. The obtained results indicated a percentage of polymorphism
ranging from 16% for Pst-AGC/Mse-AGT to 43% for Pst-AGC/Mse-ACA. The diversity index was comprised between 90.2% for Pst-AGC/Mse-AGT and 95.2% for Pst-AGG/Mse-AGG. One of the six primer combination analysed, namely Pst-AGG/Mse-AGG, was able to distinguish all the olive oil examined, and a similarity tree of the samples was elaborated. 相似文献
648.
In the history of stone traditional architecture there are constructive solutions which, with the same climatic conditions and materials used, produce a different final result. This result, which apparently is only a formal and figurative one, actually involves different physical–technical implications that inevitably determine, for these solutions, a different system of actions/reactions due to the change of stress of the physical environment they interact with. Starting from a constructive approach, linked to the Mediterranean culture and, in particular, to a specific declination represented by architecture from the Islamic architectural culture, the aim of the research work is to estimate how the logical–formal and physical operation of the walls of the traditional architecture, interacting with the outdoors, can be used and re-interpreted in order to assure a condition of visual comfort into internal spaces. Therefore, the attempt is that of a re-interpretation in a contemporary key, i.e. the possibility to use these solutions with the purpose of pointing out a methodological procedure which, even if referring to particular special configurations and specific visual duty in its experimental application, can be used in all types of environments; a methodology which contemplates and appraises all of the dynamics and problems linked to the sight and comfort of the average user. 相似文献
649.
Lucio D'Ilario Iolanda Francolini Andrea Martinelli Antonella Piozzi 《Dyes and Pigments》2009,80(3):343-348
Heparin–Toluidine Blue (C.I. Basic Blue 17) interaction was studied using UV–vis spectroscopic analysis of the titration of the functional groups present on the polyanion chain. The study took into consideration both the pH and relative amount of the dye as a function of the Heparin repeat unit number; formation of a dye/polysaccharide aggregate was studied under the same conditions and structural models of the two types of aggregates were proposed. As a consequence of such an investigation a new Heparin determination methodology was developed. 相似文献
650.
Biological and cultural inheritance deeply influence daily human behavior. However, individuals actively interact with bio-cultural information. Throughout their lives, they preferentially cultivate a limited subset of activities, values, and personal interests. This process, defined as psychological selection, is strictly related to the quality of subjective experience. Specifically, cross-cultural studies have highlighted the central role played by optimal experience or flow, the most positive and complex daily experience reported by the participants. It is characterized by high involvement, deep concentration, intrinsic motivation, and the perception of high challenges matched by adequate personal skills. The associated activities represent the basic units of psychological selection. Flow can therefore influence the selective transmission of biocultural information and the process of biocultural evolution. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献