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81.
New evidence and theoretical discussion on the complementarity relationships concerning different networking activities and
R&D in a local SME oriented system is presented. R&D arises a main driver of innovation and productivity, even without the
association to networking. The complementarity between diversified networking activities and R&D/innovation is generally found,
in a discrete setting. Non-strict complementarity nevertheless prevails. On the innovation side, complementarity among performance
drivers is more crucial for product/radical innovation, relatively to process innovation, which also witnesses substitutability
signals. Networking can be a complementary factor in situations where cooperation and networking are needed to achieve economies
of scale and/or to merge and integrate diverse skills, technologies and competencies. Managers and policy makers should be
aware that in order to exploit asset complementarity, possibly transformed into competitive advantages, both R&D and networking
are to be sustained and favoured. Networking elements are crucially linked to innovation dynamics; it is nevertheless innovation
that explains and drives networking, and not the often claimed mere existence of local spillovers or of a civic associative
culture in the territory. Such public good factors are likely to evolve with and be sustained by firm innovative dynamics. 相似文献
82.
83.
Kariluoto S Aittamaa M Korhola M Salovaara H Vahteristo L Piironen V 《International journal of food microbiology》2006,106(2):137-143
Fermentation of rye dough is often accompanied with an increase in folate content. In this study, three sourdough yeasts, Candida milleri CBS 8195, Saccharomyces cerevisiae TS 146, and Torulaspora delbrueckii TS 207; a control, baker's yeast S. cerevisiae ALKO 743; and four Lactobacillus spp., L. acidophilus TSB 262, L. brevis TSB 307, L. plantarum TSB 304, and L. sanfranciscensis TSB 299 originally isolated from rye sourdough were examined for their abilities to produce or consume folates. The microorganisms were grown in yeast extract-peptone-d-glucose medium as well as in small-scale fermentations that modelled the sourdough fermentation step used in rye baking. Total folate contents were determined using Lactobacillus rhamnosus (ATCC 7469) as the growth indicator organism. The microorganisms studied did not excrete folates into the media in significant amounts. Yeasts increased the folate contents of sterilised rye flour-water mixtures from 6.5 microg/100 g to between 15 and 23 microg/100 g after 19-h fermentation, whereas lactic acid bacteria decreased it to between 2.9 and 4.2 microg/100 g. Strains of Lactobacillus bulgaricus, L. casei, L. curvatus, L. fermentum, L. helveticus, Pediococcus spp., and Streptococcus thermophilus that were also tested gave folate contents after fermentation that varied between 2 and 10.4 microg/100 g. Although the four Lactobacillus spp. from sourdough consumed folates their effect on folate contents in co-cultivations was minimal. It was concluded that the increase of folate content during fermentation was mainly due to folate synthesis by yeasts. Fermentation of non-sterilised flour-water mixtures as such resulted in three-fold increases in the folate contents. Two folate producing bacteria were isolated from the non-sterilised flour and identified as Enterobacter cowanii and Pantoea agglomerans. 相似文献
84.
Alberto Gómez-Barea Bo Leckner Angel Villanueva Perales Susanna Nilsson Diego Fuentes Cano 《Applied Thermal Engineering》2013,50(2):1453-1462
Methods to increase the conversion of char and tar in fluidized bed gasifiers (FBG) are discussed, with the focus on small to medium-size biomass/waste gasifiers for power production (from 0.5 to 10 MWe). Optimization of such systems aims at (i) maximizing energy utilization of the fuel (maximizing char conversion), (ii) minimizing secondary treatment of the gas (by avoiding complex tar cleaning), and (iii) application in small biomass-to-electricity gasification plants. The efficiency of various measures to increase tar and char conversion within a gasification reactor (primary methods) is discussed. The optimization of FBG by using in-bed catalysts, by addition of steam and enriched air as gasification agent, and by secondary-air injection, although improving the process, is shown to be insufficient to attain the gas purity required for burning the gas in an engine to produce electricity. Staged gasification is identified as the only method capable of reaching the targets mentioned above with reasonable simplicity and cost, so it is ideal for power production. A promising new stage gasification process is presented. It is based on three stages: FB devolatilization, non-catalytic air/steam reforming of the gas coming from the devolatilizer, and chemical filtering of the gas and gasification of the char in a moving bed supplied with the char generated in the devolatilizer. Design considerations and comparison with one-stage FBG are discussed. 相似文献
85.
Roberto M. Amadio Charles Meyssonnier 《Electronic Notes in Theoretical Computer Science》2002,52(1):66-82
We study the decidability of a reachability problem for various fragments of the asynchronous π-calculus. We consider the combination of three main features: name generation, name mobility, and unbounded control. We show that the combination of name generation with either name mobility or unbounded control leads to an undecidable fragment. On the other hand, we prove that name generation without name mobility and with bounded control is decidable by reduction to the coverability problem for Petri Nets. 相似文献
86.
Svea Becker Jeffrey Momoh Ilaria Biancacci Diana Möckel Qingbi Wang Jan-Niklas May Huan Su Lena Susanna Candels Marie-Luise Berres Fabian Kiessling Maximilian Hatting Twan Lammers Christian Trautwein 《Small (Weinheim an der Bergstrasse, Germany)》2023,19(43):2208042
Fasting has many health benefits, including reduced chemotherapy toxicity and improved efficacy. It is unclear how fasting affects the tumor microenvironment (TME) and tumor-targeted drug delivery. Here the effects of intermittent (IF) and short-term (STF) fasting are investigated on tumor growth, TME composition, and liposome delivery in allogeneic hepatocellular carcinoma (HCC) mouse models. To this end, mice are inoculated either subcutaneously or intrahepatically with Hep-55.1C cells and subjected to IF for 24 d or to STF for 1 d. IF but not STF significantly slows down tumor growth. IF increases tumor vascularization and decreases collagen density, resulting in improved liposome delivery. In vitro, fasting furthermore promotes the tumor cell uptake of liposomes. These results demonstrate that IF shapes the TME in HCC towards enhanced drug delivery. Finally, when combining IF with liposomal doxorubicin treatment, the antitumor efficacy of nanochemotherapy is found to be increased, while systemic side effects are reduced. Altogether, these findings exemplify that the beneficial effects of fasting on anticancer therapy outcomes go beyond modulating metabolism at the molecular level. 相似文献
87.
We study a highly simplified version of the proposed mobility support in version 6 of Internet Protocols (IP). We concentrate on the issue of ensuring that messages to and from mobile agents are delivered without loss of connectivity. We provide three models, of increasingly complex nature, of a network of routers and computing agents that are interconnected via the routers: the first is without mobile agents and is treated as a specification for the next two; the second supports mobile agents, and the third additionally allows correspondent agents to cache the current location of a mobile agent. Following a detailed analysis of the three models to extract invariant properties, we show that the three models are related by a suitable notion of equivalence based on barbed bisimulation. Finally, we report on some experiments in simulating and verifying finite state versions of our model. 相似文献
88.
Design and implementation of mechanical resonators for optimized inertial electromagnetic microgenerators 总被引:1,自引:1,他引:0
Christophe Serre Alejandro Pérez-Rodríguez Nuria Fondevilla Emile Martincic Susanna Martínez Joan Ramon Morante Josep Montserrat Jaume Esteve 《Microsystem Technologies》2008,14(4-5):653-658
This work describes the design and implementation of an electromagnetic inertial microgenerator for energy scavenging from
ambient vibrations. The structure of the device is based in a mechanical resonator formed by a permanent magnet (inertial
mass) mounted on a polymeric membrane, in combination with a fixed micromachined coil. ANSYS simulations are carried out to
investigate the influence of the resonator geometry on the resonant frequency and on the parasitic damping, and to analyze
the optimum geometry of the coil for optimization of the electromagnetic coupling in the devices. Generator prototypes have
been fabricated with a modular manufacturing process in which the electromagnetic converter and the mechanical resonator are
manufactured separately, diced and then assembled. The experimental results show the ability of these devices to generate
power levels in the range of 50 μW with output voltages in the range of hundreds of mV. The parasitic damping of the resonator
structures is estimated from the fitting of the experimental data, and suggests the existence of an intrinsic limitation of
the polymers related to spring stiffening effects at large excitation amplitudes. The comparison of the simulations and the
experimental results indicate that further optimizations of this parameter and of the coil series resistance would allow increasing
the generated power in more than one order of magnitude. 相似文献
89.
Nilsson S Johansson BJ Jönsson A 《IEEE transactions on visualization and computer graphics》2011,17(10):1380-1392
This paper presents a study where Augmented Reality (AR) technology has been used as a tool for supporting collaboration between the rescue services, the police and military personnel in a crisis management scenario. There are few studies on how AR systems should be designed to improve cooperation between actors from different organizations while at the same time supporting individual needs. In the present study, an AR system was utilized for supporting joint planning tasks by providing organization specific views of a shared map. The study involved a simulated emergency event conducted in close to real settings with representatives from the organizations for which the system is developed. As a baseline, a series of trials without the AR system was carried out. Results show that the users were positive toward the AR system and would like to use it in real work. They also experience some performance benefits of using the AR system compared to their traditional tools. Finally, the problem of designing for collaborative work as well as the benefits of using an iterative design processes is discussed. 相似文献
90.