Search results for "CONST"
showing 10 items of 7706 documents
Mobile information systems - executives' view
1997
The concepts of travelling executive and executives' mobile information system are first defined in this paper. The main findings are in the form of collected data and opinions concluded from our personal discussions with 49 executives in the United Kingdom, France, Italy and Finland concerning the nature of the work of executives and the usage of information technology (IT) to support their work today. The near future expectations of the executives are also analysed, especially concerning the mobile use of IT services in order to construct executives' holistic view of mobile computing. The use of IT services was found to be very widespread. Big differences were found: some of the executive…
Human Simulation: A Transdisciplinary Approach to Studying Societal Problems
2019
In this chapter, we present a transdisciplinary framework where humanities scholars, social scientists, and engineers can work together to tackle large and complex societal problems. We identify the steps required to construct a human simulation model and the concerns and issues that must be addressed to ensure success. We also present some basic definitions and assumptions inherent to developing this sort of model.
Tentative Reflections on Construction of Assessment Models for Buildings’ Sustainability Certification
2017
All over the word several rating systems have been produced to certificate the sustainability level of buildings. Experts agree on considering sustainability a typical field for multicriteria decision analysis, but buildings’ rating systems do not comply in a consistent manner this assessment approach. Proposals for using classical and hybrid ranking procedures are aimed to quantify the relative attractiveness of buildings, but do not give information on their absolute attractiveness. While several studies propose suitable application of multicriteria decision making techniques for assessing buildings’ sustainability with the purpose of choosing the best solution or obtaining a ranking on a…
A comparative account of quantum dynamics of the H+ + H2 reaction at low temperature on two different potential energy surfaces
2014
Rotationally resolved reaction probabilities, integral cross sections, and rate constant for the H+ + H2 (v = 0, j = 0 or 1) → H2 (v′ = 0, j′) + H + reaction are calculated using a time-independent quantum mechanical method and the potential energy surface of Kamisaka et al. [J. Chem. Phys.116, 654 (2002)] (say KBNN PES). All partial wave contributions of the total angular momentum, J, are included to obtain converged cross sections at low collision energies and rate constants at low temperatures. In order to test the accuracy of the KBNN PES, the results obtained here are compared with those obtained in our earlier work [P. Honvault et al. , Phys. Rev. Lett.107, 023201 (2011)] using the ac…
Estimation of peak capacity based on peak simulation.
2018
Peak capacity (PC) is a key concept in chromatographic analysis, nowadays of great importance for characterising complex separations as a criterion to find the most promising conditions. A theoretical expression for PC estimation can be easily deduced in isocratic elution, provided that the column plate count is assumed constant for all analytes. In gradient elution, the complex dependence of peak width with the gradient program implies that an integral equation has to be solved, which is only possible in a limited number of situations. In 2005, Uwe Neue developed a comprehensive theory for the calculation of PC in gradient elution, which is only valid for certain situations: single linear …
Answering Schrödinger's "What Is Life?"
2020
In his &ldquo
Peak dispersion in gradient elution: An insight based on the plate model.
2020
Gradient elution in liquid chromatography reduces the analysis time, improves the efficiency and increases the peak capacity. The study of this chromatographic mode has been based mainly on kinetic dispersion models. The plate model has been applied to a lesser extent, despite being the basis for the concepts of plate height and chromatographic efficiency. In this work, a general equation describing peak dispersion in HPLC gradient elution is derived from the plate model. This equation is studied and validated for three types of gradients: (i) a reference gradient without ramp in which the retention factor varies with time identically throughout the column, (ii) a gradient of stationary pha…
A thermodynamically consistent cohesive-frictional interface model for mixed mode delamination
2016
Abstract A new interface constitutive model based on damage mechanics and frictional plasticity is presented. The model is thermodynamically consistent, it is able to accurately reproduce arbitrary mixed mode debonding conditions and it is proved that the separation work is always bounded between the fracture energy in mode I and the fracture energy in mode II. Analytical results are given for proportional loading paths and for two non-proportional loading paths, confirming the correct behavior of the model for complex loading histories. Numerical and analytical solutions are compared for three classical delamination tests and frictional effects on 4ENF are also considered.
In-process tool rotational speed variation with constant heat input in friction stir welding of AZ31 sheets with variable thickness
2017
In the present work, friction stir welding experiments on AZ31 magnesium alloy sheets, characterized by a variable thickness along the welding line, were carried out. The approach adapted during welding consisted in maintaining constant the heat input to the joint. To this purpose, the rotational speed of the pin tool was increased with decreasing thickness and decreased with increasing thickness in order to obtain the same temperatures during welding. The amount by which the rotational speed was changed as a function of the sheet thickness was defined on the basis of the results given by FEM simulations of the FSW process. Finally, the effect of the in-process variation of the tool rotatio…
Size control of InAs∕InP(001) quantum wires by tailoring P∕As exchange
2004
The size and emission wavelength of self-assembled InAs∕InP(001) quantum wires (QWrs) is affected by the P∕As exchange process. In this work, we demonstrate by in situ stress measurements that P∕As exchange at the InAs∕InP interface depends on the surface reconstruction of the InAs starting surface and its immediate evolution when the arsenic cell is closed. Accordingly, the amount of InP grown on InAs by P∕As exchange increases with substrate temperature in a steplike way. These results allow us to engineer the size of the QWr for emission at 1.3 and 1.55 μm at room temperature by selecting the range of substrate temperatures in which the InP cap layer is grown.