Web Acceptance and Usage Model: A Comparison between Goal-directed and Experiential Web Users

In this paper we analyse the Web acceptance and usage between goal-directed users and experiential users, incorporating intrinsic motives to improve the particular and explanatory TAM value –traditionally related to extrinsic motives-. A field study was conducted to validate measures used to operationalize model variables and to test the hypothesised network of relationships. The data analysis method used was Partial Least Squares (PLS).The empirical results provided strong support for the hypotheses, highlighting the roles of flow, ease of use and usefulness in determining the actual use of the Web among experiential and goal-directed users. In contrast with previous research that suggests that flow would be more likely to occur during experiential activities than goal-directed activities, we found clear evidence of flow for goal-directed activities. In particular the study findings indicate that flow might play a powerfulrole in determining the attitude towards usage,intention to useand, in turn,actual Web use among experiential and goal-directed users

Relapse of incisor crowding: a visit to the prince of salina

The management of the retention period after comprehensive orthodontic treatment is of great importance, as a primary goal of clinician. Considerable controversy still surrounds the problem of stability after the retention period. Many studies analyze factors associated to the presence of crowding or incisor irregularity and find predictive features on its relapse. Most studies have reported little o no correlation between the treatment changes in the biological parameters - clinical, biometric (irregularity index, intermolar width, intercanine width, arch length, overjet, overbite), or cephalometric variables- that ocurred and the posttretament and postretention changes that may predict their future development. This article provides a bibliographical overview on the relapse of dental alignment in treated cases. In a brief historical introduction, the first studies on the long-term stability of orthodontic results are analysed. The article then goes on to assess studies that focus attention on anteroinferior alignment before finally studying relapse of upper crowding. It concludes by making some final comments in the light of the bibliography provided and the differents schools regarding retention needs and methods

A procedure for accurate noise measurements of one port devices with high reflection coefficients

This work presents a procedure to reduce effectively the uncertainty of noise measurements of highly reflective one-port DUT's. This procedure consists of inserting an attenuator between the calibration reference plane and the DUT. The measurement RSS uncertainty has been calculated analytically and an excellent improvement of the accuracy and repeatability has been obtained when attenuations of moderate values were used

Noise performance of submicron HEMT channels under low power consumption operation

We have investigated the noise performance of HEMT devices for low noise operation with the aim of developing a noise model valid for low power biasing. Analytical expressions useful for CAD models have been derived for the calculation of the Pospieszalski gate and drain temperatures, and have been verified from near pinchoff conditions up to usual bias voltages. An overshoot in the drain temperature as a function of the drain voltage has been observed at low drain currents in deep submicron gate lenght devices

Advances in the modeling and dynamic simulation of reeving systems using the arbitrary Lagrangian–Eulerian modal method

This article is licensed under a Creative Commons Attribution 4.0 International License, which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons licence, and indicate if changes were made.This paper presents new advances in the arbitrary Lagrangian–Eulerian modal method (ALEM) recently developed for the systematic simulation of the dynamics of general reeving systems. These advances are related to a more convenient model of the sheaves dynamics and the use of axial deformation modes to account for non-constant axial forces within the finite elements. Regarding the sheaves dynamics, the original formulation uses kinematic constraints to account for the torque transmission at the sheaves by neglecting the rotary inertia. One of the advances described in this paper is the use of the rotation angles of the sheaves as generalized coordinates together with the rope-to-sheave no-slip assumption as linear constraint equations. This modeling option guarantees the exact torque balance at the sheave without including any nonlinear kinematic constraint. Numerical results show the influence in the system dynamics of the sheave rotary inertia. Regarding the axial forces within the finite elements, the original formulation uses a combination of absolute position coordinates and transverse local modal coordinates to account for the rope absolute position and deformation shape. The axial force, which only depends on the absolute position coordinates, is constant along the element because linear shape functions are assumed to describe the axial displacements. For reeving systems with very long rope spans, as the elevators of high buildings, the constant axial force is inaccurate because the weight of the ropes becomes important and the axial force varies approximately linearly within the rope free span. To account for space-varying axial forces, this paper also introduces modal coordinates in the axial direction. Numerical results show that a set of three modal coordinates in the axial direction is enough to simulate linearly varying axial forces.Unión Europea - Horizon 2020 Marie Skłodowska-Curie No 860124, THREAD

Dynamic simulation of reeving systems with the extension of the modal approach in the axial direction

Proceedings of the ASME 2021 International Design Engineering Technical Conferences and Computers and Information in Engineering Conference. Volume 9: 17th International Conference on Multibody Systems, Nonlinear Dynamics, and Control (MSNDC). Virtual, Online. August 17–19, 2021. V009T09A015. ASME.In this work, the simulation of reeving systems has been studied by including axial modes using the Arbitrary Lagrangian-Eulerian (ALE) description. The reeving system is considered as a deformable multibody system in which the rigid bodies are connected by the elastic wire ropes through sheaves and reels. A set of absolute nodal coordinates and modal coordinates is employed to describe the motion and deformation in the axial direction. This new method allows the analysis of elements with non-constant axial strain along its length. In addition, modal coordinates are employed to describe the dynamic motion in the transverse direction. The non-constant axial displacement within the wire rope is computed in terms of the absolute position coordinates, longitudinal material coordinates, and modal deformation coordinates. To derive the governing equations of motion, Lagrange's equation is employed. The formulation is validated for a simple pendulum-like motion actuated by an initial velocity. The simulation results are provided to trace the movements of the payload. It can be seen that by adding modal coordinates, the axial force within the element changes. Moreover, the effects of modal coordinates in the axial direction are presented for a different number of nodes, and the resulting axial forces are compared with reference solution.Unión Europea - Horizon 2020 Marie Skłodowska-Curie project No. 860124 (THREAD

EDMS Use in Local E-Government: Extent of Use and Overall Performance Mediated by Routinization and Infusion

This study analyzes the effects of several post-adoption behaviors (extent of use, routinization and infusion) on overall performance in using an Electronic Document Management System (EDMS). Furthermore, we test whether the routinization and infusion variables mediate the influence of the extent of use on overall performance. This research collects data from a survey answered by 2,175 employees (EDMS users) of Portuguese municipalities. The Partial Least Squares technique is applied to test the model. The results showed that routinization is directly predicted by the extent of use, whereas infusion is directly affected by the extent of use and also by routinization. Consequently, such post-adoptive behaviors are interrelated not only in a sequential process, but also in parallel. In addition, overall performance is directly influenced by routinization and infusion. Finally, an indirect effects analysis shows that routinization and infusion mediate the relationship between extent of use and overall performance

Uso eficiente y ahorro de energía eléctrica en el colegio Inem Felipe Pérez: una visión estratégica desde la educación ambiental

El uso inadecuado de los recursos naturales, ha repercutido especialmente en los recursos hídricos; cada vez es más evidente el agotamiento de las fuentes hídricas, como consecuencia de los múltiples factores climáticos, de contaminación y de consumo acelerado de energía eléctrica por el uso excesivo de aparatos electrónicos, equipos y electrodomésticos. Planteada dicha problemática ambiental y social, se han delegado funciones y soluciones impartidas desde la educación. Especialmente la educación dirigida a niños y jóvenes, a través de los proyectos ambientales escolares PRAES. Para el presente proyecto se realizo un diagnostico de consumo de energía en la institución educativa INEM FELIPE PÉREZ, buscando áreas de oportunidad en materia de ahorro de energía con el propósito de generar una propuesta en la que se ahorre electricidad, lo cual se traduce a una disminución de los impactos ambientales generados por dicho consumo, además de la sensibilización a la comunidad educativa involucrando dicho proyecto en el PRAES.Improper use of natural resources, has especially affected the water resources is increasingly evident depletion of water sources as a result of multiple climatic factors, pollution and energy consumption accelerated by overuse of electronics, computers and appliances. Raised environmental and social problems that have been delegated functions and taught from education solutions. Especially education to children and youth through school PRAES environmental projects. For this project a diagnosis of energy consumption in the school INEM FELIPE PÉREZ, looking for areas of opportunity in terms of energy saving for the purpose of generating a proposal that will save electricity, which translates to a was performed reduction of environmental impacts caused by energy consumption, in addition to raising the educational community project involving PRAES said

Long-term analysis of upper incisor crowding. A longitudinal study orthodontically treated patients

Introduction: Although there are numerous studies in the literature on alignment stability in the lower arch, there are few referring to the upper arch. Aims: To assess upper arch stability (irregularity index, widths and length of arch, overjet and overbite) in orthodontically treated patients by comparing late incisor stability with the initial malocclusion and type pf treatment undertaken. Study design: The study models of 51 patients, treated with or without extractions, were analysed at three different points in time: pre-treatment (T1), post-treatment (T2) and post-retention (T3) (average 5 years). The following parameters were measured: irregularity index, arch length, inter-canine and inter-molar widths, overjet and overbite. Results: The results showed that upper incisor crowding relapses, although a net improvement is noted in comparison to the initial state both in cases treated with or without extractions. The arch length also relapses in both cases. The inter-canine and inter-molar widths as well as the overjet and overbite are stable in the long term. The long-term response of maxillary incisor alignment is unpredictable. Conclusions: There is a statistically significant reduction in incisor irregularity, length and width of arch (inter-canine and inter-molar widths), whereas overjet and overbite undergo a reduction of little magnitude. No statistically significant correlation is noted between late incisor stability and the initial malocclusion or type of treatment