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991.
The aim of the present study is to analyse factors affecting worries, coping strategies and decisions of young drivers regarding the risk of sleep-related car crashes. Furthermore, the study also analyses whether framing the same information about sleepiness in two different linguistic forms influences: (1) the evaluation of the level of risk associated to a specific level of drowsiness (Attribute Framing problem); (2) the willingness to enact strategies to "prevent" sleepiness before night-time driving (Goal Framing problem); (3) the choice between two different ways, both of equal expected efficacy, of lowering drowsiness (Risky decision-making Framing problem). Six hundred and ninety-five young drivers [(57.6% females, 42.4% males); mean age 20.85 years (S.D.=1.2)] answered questions on drive risk perception and sleepiness, on nocturnal driving experience and on the strategies to deal with driver sleepiness, responding to one of the two different versions of the framed problems. A sub-sample of 130 participants completed the framed problems in both versions. The results show that experiences of sleep attacks and nocturnal driving frequency in the past 6 months affect both risk perception and the preventive strategies adopted. Furthermore, the manipulation on two out of the three problems (attribute and risky decision-making frames) significantly affected the respondents' evaluation.  相似文献   
992.
We present a new retrieval model designed to analyze the observations of the Michelson Interferometer for Passive Atmospheric Sounding (MIPAS), which is on board the ENVironmental SATellite (ENVISAT). The new geo-fit multitarget retrieval model (GMTR) implements the geo-fit two-dimensional inversion for the simultaneous retrieval of several targets including a set of atmospheric constituents that are not considered by the ground processor of the MIPAS experiment. We describe the innovative solutions adopted in the inversion algorithm and the main functionalities of the corresponding computer code. The performance of GMTR is compared with that of the MIPAS ground processor in terms of accuracy of the retrieval products. Furthermore, we show the capability of GMTR to resolve the horizontal structures of the atmosphere. The new retrieval model is implemented in an optimized computer code that is distributed by the European Space Agency as "open source" in a package that includes a full set of auxiliary data for the retrieval of 28 atmospheric targets.  相似文献   
993.
A Portland cement process was taken into consideration and monitored for one month with respect to polluting emissions, fuel and raw material physical-chemical properties, and operative conditions. Soft models, based on linear (partial least-squares, PLS, and principal component regression, PCR) and nonlinear (artificial neural networks, ANNs) approaches, were employed to predict the polluting emissions. The predictive ability of the three regression methods was evaluated by means of the partition of the dataset by Kohonen self-associative maps into both a training and a test set. Then, a "leave-more-out" approach, based on the use of a training set, a test set, and a production set, was adopted. The training set was used to build the models, the test set was used to select the number of latent variables or the neural network training endpoint, and the production set was used to produce genuine predictions. ANNs proved to be much more effective in prediction with respect to PLS and PCR and, at least in the case of SO2 and dust, provided a predictive ability comparable with the experimental estimated uncertainty of the response. This showed that it is possible to satisfactorily predict the two responses. Such a prediction will result in the prevention of environmental and legal problems connected to the polluting emissions.  相似文献   
994.
The aim of this paper is to analyze how the uncertainties in modelling the geometry and the material properties of a human bone affect the predictions of a finite-element model derived from computed tomography (CT) data. A sensitivity analysis, based on a Monte Carlo method, was performed using three femur models generated from in vivo CT datasets, each subjected to two different loading conditions. The geometry, the density and the mechanical properties of the bone tissue were considered as random input variables. Finite-element results typically used in biomechanics research were considered as statistical output variables, and their sensitivity to the inputs variability assessed. The results showed that it is not possible to define a priori the influence of the errors related to the geometry definition process and to the material assignment process on the finite-element analysis results. The errors in the geometric representation of the bone are always the dominant variables for the stresses, as was expected. However, for all the variables, the results seemed to be dependent on the loading condition and to vary from subject to subject. The most interesting result is, however, that using the proposed method to build a finite-element model of a femur from a CT dataset of the quality typically achievable in the clinical practice, the coefficients of variation of the output variables never exceed the 9%. The presented method is hence robust enough to be used for investigating the mechanical behavior of bones with subject-specific finite-element models derived from CT data taken in vivo.  相似文献   
995.
996.
Summary: Organic‐inorganic nanocomposite hybrid coatings were prepared through a dual‐cure process involving cationic photopolymerization of a hyperbranched epoxy functionalized resin and subsequent condensation of an alkoxysilane inorganic precursor. All the formulations investigated gave rise to photocured films characterized by high gel content values. An increase in glass transition temperature and an increase in storage modulus above Tg in the rubbery plateau is observed with increasing TEOS content in the photocurable formulation. The important role of GPTS on reducing the inorganic domain size and avoiding macroscopic phase separation was demonstrated by TEM analyses.

TEM obtained for one of the cured films in the presence of GPTS.  相似文献   

997.
A method for the parallel solid-phase synthesis of peptide aldehydes has been developed. Protected amino acid aldehydes obtained by the racemization-free oxidation of amino alcohols with Dess-Martin periodinane were immobilized on threonyl resins as oxazolidines. Following Boc protection of the ring nitrogen to yield the N-protected oxazolidine linker, peptide synthesis was performed efficiently on this resin. A peptide aldehyde library was designed for targeting the SARS coronavirus main protease, SARS-CoV M(pro)(also known as 3CL(pro)), on the basis of three different reported binding modes and supported by virtual screening. A set of 25 peptide aldehydes was prepared by this method and investigated in inhibition assays against SARS-CoV M(pro). Several potent inhibitors were found with IC(50) values in the low micromolar range. An IC(50) of 7.5 muM was found for AcNSTSQ-H and AcESTLQ-H. Interestingly, the most potent inhibitors seem to bind to SARS-CoV M(pro) in a noncanonical binding mode.  相似文献   
998.
A GIS-based procedure for predicting pesticide exposure in surface waters has been applied on a pilot river basin characterized by intensive agricultural activity. The predictive approach has been validated through experimental monitoring, performed by collecting manual and automatic water samples during the productive season. Five active ingredients (terbuthylazine, metolachlor, alachlor, linuron, fenitrothion) were selected for analysis to validate the predictive approach. Comparison between predicted and experimental values showed good agreement for terbuthylazine and metolachlor (used in large volumes within the basin), demonstrating the reliability of the approach. However, some anomalous results were obtained for some of the other chemicals, which serve to highlight the difficulties in getting reliable input data, in particular on application patterns (rate and time). Furthermore, the value of mapping pesticide exposure on the medium-large scale is described, and the limitations of the reported predictive approach are discussed.  相似文献   
999.
Fast echographic multiparameter multi-image novel apparatus (FEMMINA), is a hardware and software platform dedicated to ultrasonic signal and image processing. FEMMINA is able to operate with sequences of radiofrequency (RF) frames. Its architecture is designed to be modular, expandable, and aimed at implementing different ultrasonic investigation techniques. The first experimental characteristic of this system is in its capability to operate in real time with ultrasonic RF signals, starting from acquisition up to processing, storage, and visualization. The second characteristic is the user-system interactivity that allows one to modify the operation appropriately while observing results. Currently, FEMMINA works in both typical experimental situations to study novel investigation techniques and clinical field to validate the proposed methods in different human districts.  相似文献   
1000.
This paper presents a theoretical and experimental comparison between two charge pump architectures commonly used in CMOS integrated circuits, namely the Dickson scheme and the cascade of voltage doublers. The comparison is carried out considering power efficiency as the main feature of interest. To compare the two topologies, two charge pumps were integrated in 0.18-μm triple-well CMOS technology. The two charge pumps were designed with the same operating clock frequency, the same storage capacitance per stage, and the same number of stages (and, thus, approximately the same area). The theoretical and the experimental comparison showed that the power efficiency of the voltage doubler scheme is higher (by about 13% at ), mainly thanks to the lower parasitic capacitance associated to the boosted nodes.  相似文献   
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