Search results for "component"
showing 10 items of 1682 documents
Correction of Long Vehicle Off Tracking by Multiple Axle Steering
2019
When planning the road vehicles for the transport of passengers or goods, engineers should take care to contrast some undesirable phenomena in the lateral dynamics, such as high-speed instability or off tracking. While the former is less troubling in the slow heavy vehicles, the latter is a serious problem due to the risk of invading the neighbouring lanes. The use of multi-wheel steering may completely cancel this drawback and, pursuing an optimized correlation among the steering angles, a functional inter-dependence based on the cubic “witch of Agnesi” is found to be very promising. Simple control systems with electromechanical or electronic components may be easily implemented for the mu…
The Low-Affinity ATP Binding Site of the Escherichia coli SecA Dimer Is Localized at the Subunit Interface
1997
The homodimeric SecA protein is the ATP-dependent force generator in the Escherichia coli precursor protein translocation cascade. SecA contains two essential nucleotide binding sites (NBSs), i.e., NBS1 and NBS2 that hind ATP with high and low affinity, respectively. The photoactivatable bifunctional cross-linking agent 3'-arylazido-8-azidoadenosine 5'-triphosphate (diN(3)ATP) was used to investigate the spatial arrangement of the nucleotide binding sites of SecA, DiN(3)ATP is an authentic ATP analogue as it supports SecA-dependent precursor protein translocation and translocation ATPase, UV-induced photo-cross-linking of the diN(3)ATP-bound SecA results in the formation of stable dimeric s…
Application of PGPB Combined with Variable N Doses Affects Growth, Yield-Related Traits, N-Fertilizer Efficiency and Nutritional Status of Lettuce Gr…
2022
Nitrogen (N) fertilization is a crucial agricultural practice for boosting production traits in vegetables. However, N synthetic fertilizers—commonly adopted by farmers—have several counterproductive effects on the environment and on humans. The research was performed to assess the combined influence of plant growth promoting bacteria (PGPB) (Azospirillum brasilense DSM 1690, A. brasilense DSM 2298 and Pseudomonas sp. DSM 25356) and various N fertilization doses (0, 30, 60 or 120 kg ha−1) on growth, yield, quality and nitrogen indices of lettuce in protected cultivation. Plant height, root collar diameter, number of leaves and fresh weight were enhanced by A. brasilense DS…
Latitudinal- and local-scale variations in a rocky intertidal interaction web
2015
Natural assemblages are structured by a complex combination of positive and negative interactions, and the relative importance of each interaction can vary across spatial scales. By using a simple interaction web (barnacles-grazers-microphytobenthos) in a rocky intertidal system, we tested the hypothesis that the relative strength of positive and negative interactions would vary as a function of different environmental stress between 2 latitudinal levels and local environmental conditions. We manipulated the cover of barnacles and the presence of limpets at 2 sites in northern and southern Italy and non-destructively examined the response of microphyto - benthos (MPB) (photosynthetic biomas…
Service discovery protocols in D2D-enabled cellular networks: Reactive versus proactive
2014
Device-to-Device (D2D) communication, which allows access services offered by nearby devices bypassing the base station, has been regarded as an essential component of the emerging 5G mobile networks. Many advantages can be provided by this direct communication paradigm such as high data rate, traffic offloading, range extension, as well as proximity services and social networking. In such a context, service discovery approaches need to be investigated. In this paper, we propose two protocols for service discovery, namely, reactive (pull) discovery and proactive (push) discovery in infrastructure-coordinated D2D networks. The protocol overhead is calculated and numerical results are provide…
An adaptive-PCA algorithm for reflectance estimation from color images
2008
This paper deals with the problem of spectral reflectance estimation from color camera outputs. Because the reconstruction of such functions is an inverse problem, stabilizing the reconstruction process is highly desirable. One way to do this is to decompose reflectance function on a basis functions like PCA. The present work proposes an algorithm making PCA adaptive in reflectance estimation from a color camera output. We propose to adapt the PCA basis derivation by selecting, for each sample, the more relevant elements from the training set elements. The adaptivity criterion is achieved by a likelihood measurement. Finally, the spectral reflectance estimation results are evaluated with th…
Numerical and experimental validation of a LiFePO<inf>4</inf> battery model at steady state and transient operations
2013
In the paper some of the battery models proposed in literature are analysed in order to predict the battery performance and, then, make sure that the Battery Management System (BMS) that is a key component to check and control the status of the batteries within their specified safe operating conditions, works in best conditions. In fact to reach an extended battery lifetime and increase the reliability of the system, is necessary to guarantee an accurate evaluation of the state of the whole stack of batteries to track their operations. Therefore, an accurate battery model that captures the dynamics of the battery is required. Lithium batteries are in particular considered because of their h…
Tunable antenna system for plug&amp;play satellite avionics: Prototyping and test
2014
In the framework of an ESA program, a new architecture for plug&play compact antenna systems in the X band has been investigated and experimentally verified by many prototypes. The proposed antenna system takes inspiration from the LEGO building toys: the basic component of the new architecture is a 2.7cm-cube complex module that integrates a three-dimensional local network and a programmable mechanism based on the bonding-wire technology to select one among three polarization options. Elemental blocks can be augmented by accessories to shape the beam and may be used in array configuration over boards provided with cluster-level beamforming networks. Measurements have been performed for bot…
Combined spike-related functional MRI and multiple source analysis in the non-invasive spike localization of benign rolandic epilepsy.
2007
Abstract Objective To localize the irritative zone in children by combined spike-related fMRI and EEG multiple source analysis (MSA) in children with benign rolandic epilepsy. Methods Interictal spikes were averaged and localized using MSA, and source locations were displayed in the anatomical 3D-MRI in 11 patients (5–12 yrs, median 10). Interictal spikes were additionally recorded during the fMRI acquisition (EEG-fMRI), and the fMRI sequences were correlated off-line with the EEG spikes. Results MSA revealed an initial central dipole in all patients, including the face or hand area. A second dipolar source was mostly consistent with propagated activity. BOLD activations from EEG-fMRI, cons…
Estimation of total electricity consumption curves of small areas by sampling in a finite population
2016
International audience; Many studies carried out in the French electricity company EDF are based on the analysis of the total electricity consumption curves of groups of customers. These aggregated electricity consumption curves are estimated by using samples of thousands of curves measured at a small time step and collected according to a sampling design. Small area estimation is very usual in survey sampling. It is often addressed by using implicit or explicit domain models between the interest variable and the auxiliary variables. The goal here is to estimate totals of electricity consumption curves over domains or areas. Three approaches are compared: the rst one consists in modeling th…