Search results for "force"
showing 10 items of 3423 documents
Discotic Twin and Triple Molecules with Charge-Transfer Interactions in Langmuir−Blodgett Films
1996
X-ray and atomic force microscopy observations reveal features of the surface morphology of Langmuir-Blodgett (LB) films from discotic donor-acceptor molecules with strong core-to-core interactions caused by a charge-transfer (CT) complexation. The compounds are designed to be twin and triple molecules composed of chemically connected donor (triphenylene) and acceptor (trinitrofluorenone) fragments which display liquid crystalline structure in the bulk state. The LB films from these compounds possess edge-on orientation of molecules within monolayers with a smooth surface on a submicron scale but with substantial macroscopic imperfections. These imperfections are represented by the micron s…
Le niveau de compétences de base peut-il expliquer le déclassement ou le surclassement sur le marché du travail ?
2013
Documents de travail de l'IREDU, n°2013-3; Cet article porte sur le lien entre le déclassement et le surclassement sur le marché du travail et les compétences de base qu'ont pu acquérir les individus au cours de leurs parcours scolaire et professionnel. En observant une certaine hétérogénéité des compétences de base par niveau de diplôme, nous faisons l'hypothèse que ces différences peuvent expliquer les situations de déclassement ou de surclassement. Nos travaux, à partir des données de l'enquête nationale " Information et Vie Quotidienne " (2004), montrent effectivement que les situations de déclassement (surclassement), pour un même niveau de diplôme, peuvent résulter d'un plus faible (f…
La Direttiva 2014/104/UE sul risarcimento dei danni per violazione della normativa antitrust dell'Unione Europea e la sua attuazione in Italia
2019
Con il d.lg. 13 gennaio 2017, n. 3, è stata data attuazione alla direttiva 2014/104/UE del Parlamento e del Consiglio del 26 novembre 2014, relativa a determinate norme che regolano le azioni per il risarcimento del danno ai sensi del diritto nazionale per violazioni delle disposizioni del diritto della concorrenza degli Stati membri e dell'Unione europea. Il saggio esamina criticamente le novità e le principali questioni interpretative poste dal nuovo testo. With the legislative decree 13 January 2017, n. 3, has been implemented in Italy the 2014/104 / EU directive of the Parliament and of the Council of 26 November 2014 , concerning certain rules governing actions for damages under nation…
On the feasibility of personal audio systems over a network of distributed loudspeakers
2018
Los sistemas de reproducción de audio personal se ocupan de la creación de zonas sonoras personales dentro de una habitación sin necesidad de utilizar auriculares. Estos sistemas utilizan un conjunto de altavoces y diseñan los filtros necesarios en cada altavoz con el fin de que la señal de audio deseada llegue a cada persona en la sala lo más libre de interferencias posible. Existen propuestas muy interesantes en la literatura que hacen uso de arrays circulares o lineales, pero en este trabajo estudiamos el problema considerando una red de altavoces distribuidos controlados por un conjunto de nodos acústicos, que pueden intercambiar información a través de una red. Enunciamos el modelo de …
Multitasking in Driving as Optimal Adaptation Under Uncertainty
2021
Objective The objective was to better understand how people adapt multitasking behavior when circumstances in driving change and how safe versus unsafe behaviors emerge. Background Multitasking strategies in driving adapt to changes in the task environment, but the cognitive mechanisms of this adaptation are not well known. Missing is a unifying account to explain the joint contribution of task constraints, goals, cognitive capabilities, and beliefs about the driving environment. Method We model the driver’s decision to deploy visual attention as a stochastic sequential decision-making problem and propose hierarchical reinforcement learning as a computationally tractable solution to it. The…
Simplified analytical model for moment–axial force domain in the presence of shear in R.C. members externally strengthened with steel cages
2015
Equations for a hand calculation of moment–axial force domain in the presence of shear for R.C. beam/column externally strengthened with steel angles and strips are developed. The analytical derivation is made assuming, for axial load and flexure, the equivalent stress-block parameters for internal forces, considering the confinement effects induced in the concrete core by external cages both in the cases of strips or angles yielding. Limit states due to bond failure, concrete crushing and yielding of steel angles and strips in flexure and in shear, including moment-to-shear interaction, are considered. The proposed model gives results in a good agreement with available experimental data an…
Microwave-Assisted Organocatalytic Enantioselective Intramolecular aza-Michael Reaction with α,β-Unsaturated Ketones
2011
An organocatalytic enantioselective intramolecular aza-Michael reaction of carbamates bearing conjugated ketones as Michael acceptors is described. By using 9-amino-9-deoxy-epi-hydroquinine as the catalyst and pentafluoropropionic acid as a co-catalyst, a series of piperidines, pyrrolidines, and the corresponding benzo-fused derivatives (indolines, isoindolines, tetrahydroquinolines, and tetrahydroisoquinolines) can be obtained in excellent yields and enantioselectivities. In addition, the use of microwave irradiation at 60 °C improves the efficiency of the process giving rise to the final products with comparable yields and enantiomeric excesses. Some mechanistic insights are also consider…
Generic Method for Modular Surface Modification of Cellulosic Materials in Aqueous Medium by Sequential Click-Reaction and Adsorption
2012
A generic approach for heterogeneous surface modification of cellulosic materials in aqueous medium, applicable for a wide range of functionalizations, is presented. In the first step, carboxymethyl cellulose (CMC) modified with azide or alkyne functionality, was adsorbed on a cellulosic substrate, thus, providing reactive sites for azide–alkyne cycloaddition click reactions. In the second step, functional units with complementary click units were reacted on the cellulose surface, coated by the click-modified CMC. Selected model functionalizations on diverse cellulosic substrates are shown to demonstrate the generality of the approach. The concept by sequentially combining the robust physic…
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…
Accessibility of eGovernment Web Sites: Towards a Collaborative Retrofitting Approach
2010
Published version of a chapter from the book: Computers Helping People with Special Needs.The original publication is available at www.springerlink.com: http://dx.doi.org/10.1007/978-3-642-14097-6_75 Accessibility benchmarking is efficient to raise awareness and initiate competition. However, traditional benchmarking is of little avail when it comes to removing barriers from eGovernment web sites in practice. Regulations and legal enforcement may be helpful in a long-term perspective. For more rapid progress both vendors and web site maintainers are willing to take short-term action towards improvements, provided that clear advise is available. The approach of the eGovernment Monitoring pro…