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21.
In this paper a reaction-diffusion CNN is implemented to generate and adaptively control locomotion in a biologically inspired walking robot. In particular a dedicated CNN development system has been realised to make the mechatronic device able to select, based on sensory stimuli, the most suitable locomotion type according to the environment. The first example of analog implementation of the biological paradigm of the Central Pattern Generator is therefore presented.  相似文献   
22.
The catalytic pattern of several oxide carriers (MgO, Al2O3, ZrO2, TiO2, SiO2, HY zeolite) and supported V2O5 (4.7–5.3 wt%) catalysts in the oxidative dehydrogenation of propane to propylene (PODH) has been comparatively investigated. The fundamental role of the oxide support on both reducibility and reactivity of vanadia catalysts has been assessed. A direct relationship between the specific surface activity of oxide carriers and that of vanadia catalysts is discussed. The inverse relationship between the specific activity and the onset temperature of reduction marks the prevailing redox behaviour of V2O5 catalysts in the PODH reaction. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   
23.
Vanadium pentoxide (V2O5) nanocrystals having few tens nanometers average size, are obtained from ammonium metavanadate (NH4VO3) in the presence of oleic acid, and treating the reaction product at 400 °C. Nanocrystalline films, deposited from stable ethanol suspensions of the V2O5 nanopowder, adhere strongly to different kinds of substrates, without the need of any thermal post processing. At room temperature, the films are found to bleach when exposed to ammonia. Bleaching originates from the formation of ammonium metavandate, and is reversible, as after annealing in air at 350 °C, ammonium metavanadate converts back to V2O5. Formation of ammonium metavanadate, clearly evidenced by remarkable changes in infrared spectrum of V2O5 films exposed to ammonia, is a valuable detection mechanism, promising in view of developing highly selective ammonia sensors operating at room temperature.  相似文献   
24.
The novel rhodium complex [Rh(S)‐Phanephos(cod)]‐catalyzed hydrogenation of disubstituted (E)‐enol acetate carboxylic acids is reported. The catalytic cycle works under 30 bar of hydrogen under conventional heating giving different 3‐acetoxy‐2,3‐disubstituted carboxylic acids with ee ≥90%. Hydrogenation occurred also under microwave dielectric heating without eroding the enantioselectivity but improving the overall efficiency of the process. With microwaves, hydrogen pressure and reaction time required for complete hydrogenation dropped to 5 bar and 30 min, respectively. The best performance of this catalyst under microwave irradiation was TON 100, TOF 196 h−1 with ee 99% on a 6‐g scale.  相似文献   
25.
BACKGROUND: Lactobacillus hilgardii, a wine lactic acid bacterium, is able to use arginine, through the arginine deiminase pathway with the formation of citrulline, a precursor of the carcinogen ethyl carbamate. The influence of different Argentine wine varieties (Merlot, Cabernet Sauvignon and Malbec), on bacterial growth and arginine metabolism was examined. Furthermore, the effect of different components normally present in wines on the enzyme activities of the arginine deiminase system was determined. RESULTS: Malbec wine under all conditions assayed (33, 50 and 100% supplemented wine:basal media) showed higher arginine consumption and citrulline production than the other wines, as well as the highest bacterial growth and survival of Lactobacillus hilgardii X1B. Glucose and L ‐malic inhibited both arginine deiminase enzymes while fructose and citric acid only inhibited arginine deiminase. The red wines assayed in this study had different composition, and this is an explanation for the different behavior of the bacterium. CONCLUSION: The highest citrulline production in Malbec wine could be correlated with its lower concentrations of glucose, fructose, citric and phenolic acid than the other wines. Therefore, a wine with lower concentration of these sugars and acids could be dangerous due to the formation of ethyl carbamate precursors. Copyright © 2012 Society of Chemical Industry  相似文献   
26.
This paper describes a microcontroller-based multichannel telemetry system, suitable for in vivo monitoring of physiological parameters. The device can digitalize and transmit up to three analog signals coming from different sensors. The telemetry transmission is obtained by using a carrier frequency of 433.92 MHz and an amplitude-shift keying modulation. The signal data rate is 13 kb/s per channel. The digital microcontroller provides good flexibility and interesting performance, such as the threshold monitoring, the transmission error detection, and a low power consumption, thanks to the implementation of a sleep mode. The small overall size (less than 1 cm3), the power density compatible with current regulations for the design of implantable devices, and the dedicated packaging make the system suitable for in vivo monitoring in humans. The design, fabrication, operation, packaging, and performance of the system are described in this paper. An in vivo pressure monitoring case study is described as well.  相似文献   
27.
Twenty patients with histologically documented superficial bladder cancer (Ta, T1, Tis) were treated with intravesical administration of TNF 400-1800 micrograms. Of 18 patients with a marker lesion, 2 obtained a complete response for 8+ and 18 months. Two had a partial response and were given other intravesical therapies after 5 and 7 months. No or minimal systemic absorption of TNF was observed and documented in 4 of 20 patients by pharmacokinetic studies, and no patients developed antibodies to intravesically administered TNF. TNF was well tolerated in doses up to 1800 micrograms. No systemic or local side effects were observed. Modest activity was attained with intravesical TNF, even in pretreated patients.  相似文献   
28.
CO adsorption on high loading Ni/MgO samples treated at 800 and 900°C has been studied by using IR spectroscopy. Linear and bridged monocarbonyls are produced under low CO pressure and the Boudouard reaction occurs producing C, adsorbed on the metal particles, and CO2, stabilized on the MgO matrix. Effects of hydrogen and carbon on surface reactivity have been studied. The morphology of the catalysts and of carbonaceous deposits produced by heating in CO at high temperature are examined by HRTEM.  相似文献   
29.
The paper presents a set of experiments on the Rolling Horizon Technique (RHT), applied to the management of a multi-reservoir, multipurpose water resources system with over-year behaviour. In the RHT, decisions on releases from reservoirs are taken for a number of time steps ahead (the Forecasting Horizon – FH) through an optimization model, based on the present water availability in reservoirs and on some forecasts of future inflows over the FH. Only the decision concerning the first time step (the current month) is then implemented, as new information on reservoir levels and forecasts becomes available so that the process can start again with updated information. The paper investigates how the quality of forecasts and the length of the FH impact on the effectiveness of the decisions taken. The evaluation exercise is carried out in two different demand scenarios considering some deficit-related indices, such as TSSD, the Sum of Squared Standardized Deficits, over an Operation Horizon (OH) of forty years. The scenarios are designed to evaluate the role of different demand levels (corresponding to higher/lower stress) on system’s behaviour. Results show that in systems with over-year behaviour, effective forecasts (here simulated through the best possible: actually occurred inflows from the current month up to the end of water year) seem to add little value to system’s operation compared to the most naive forecast (average monthly values), especially in contexts characterized by high pressure on resources. Where there is less pressure on resources, good-quality forecasts are more effective to improve operation. A FH of 24 months seems to enhance significantly system’s performances compared to a FH of 12 months, while FHs longer than two years produce no improvements in system’s performances. The paper also tries to define the limits of a finite-horizon operation technique such as the RHT by benchmarking it with an idealistic release schedule obtained by a model that performs allocation with Perfect Foresight over the whole Operation Horizon.  相似文献   
30.
The industrial domain is experiencing a so-called fourth industrial revolution in which the evergrowing complexity of manufacturing information, the increasing amount of knowledge and the use of web-oriented techniques, represent three crucial factors that are accelerating the growth of complexity of industrial systems. On the other hand, continuous-evolving requirements in industrial environments, due to technology outbreaks and a new global marketplace, have led to an on-going evolution of human resource management through the creation and adoption of alternative business models. In the past decade, semantic models such as ontologies have been proven to be effective for many knowledge-intensive applications, since they provide formal models of domain knowledge that can be exploited in different ways. For all these reasons, an innovative human resource optimisation (HRO) engine is introduced, which employs semantically enhanced information and conditional random field (CRFs) probabilistic models with knowledge derived from industrial shop floor level, and proposes the right person for the right job in real-time shop floor operations towards optimising decisions on how to implement and schedule either repeatedly or non-occurring tasks. Industrial information data flow and semantic enrichment were ensured through the combined use of a common interface data exchange model (CIDEM) and ontologies, after which a feasibility study at a chemical plant presented interesting preliminary results.  相似文献   
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