Boundary controllability for finite-differences semi-discretizations of a clamped beam equation

This article deals with the boundary observability properties of a space finite-differences semi-discretization of the clamped beam equation. We make a detailed spectral analysis of the system and, by combining numerical estimates with asymptotic expansions, we localize all the eigenvalues of the corresponding discrete operator depending on the mesh size $h$. Then, an Ingham's type inequality and a discrete multiplier method allow us to deduce that the uniform (with respect to $h$) observability property holds if and only if the eigenfrequencies are filtered out in the range $O(1/hˆ4)$

NUMERICAL MODELING AND DESIGN OF LOW-RISE CONCENTRICALLY BRACED FRAMES WITH DOUBLE-PIN DISSIPATIVE CONNECTIONS

Concentrically braced frames, CBFs, are the most popular systems used in seismic areas in Canada, due to their large stiffness. However, after braces buckle in compression, their stiffness is significantly reduced and their hysteresis response, displayed in terms of force-displacement, shows an asymmetric behavior. To overcome this drawback, researchers proposed to add fuses that were conceived to be installed either in braces or brace-to-frame connections. The purpose of these fusses is to dissipate the earthquake input energy, while preserving braces to respond in elastic range. In this thesis, a new type of fuse, designed to be installed in brace-to-frame connections, is proposed. This device is labeled dissipative pin connection. Depending on the level of axial tension/ compression force that has to be transferred from the brace to the connection, this device can be manufactured in single-pin, double-pin and multi-pin configurations. The objective of this thesis was two-fold: i) to develop design rules for double-pin connections displayed in-line and in-parallel and ii) to study the seismic response of a 4-storey CBF building with and without dissipative connections, located in Victoria, BC. In this thesis, the computations were carried out by means of OpenSees (open system for earthquake engineering simulation). The numerical model developed for single-pin connection was calibrated based on experimental tests carried out at the Technical University of Lisbon. Similarly, the double-pin connection was calibrated using the same approach. Based on experimental test results conducted on single pin connections, design rules were proposed. It was concluded that by doubling the pin member and employing the parallel configuration, the load-carrying capacity of the dissipative connection increases two times, while the deflection is similar to that experienced by an equivalent single-pin device. The second part of this thesis emphasizes comparative results, in terms of seismic response of a 4-storey CBF building with and without dissipative connections. Building design was conducted according to S16-2009 and NBCC 2010 provisions. The seismic response was studied under two sets of ground motions that are representative for Victoria, BC: crustal and subduction events. The results have shown that forces generated in structural members were reduced due to an increase in building period and system ductility. Thus, by lowering the axial force developed in the CBF columns, a reduction of foundation size can be achieved which implies reduction in the overall building cost. The effect of earthquake type on the building response is also discussed. However, to prove the efficiency of double-pin connections displayed in-line and in-parallel, further experimental tests are required

Considerations on the criteria, parameters and tax implications of depreciation

The literature presents several methods of depreciation. In Romania, not all depreciation methods are recommended by existing legislation. In this paper we propose to address through the income tax three methods of depreciation of assets, which are recommended by our country's legislation, and to highlight the tax benefits of their application within the entities. In the first part we propose to define what are the criteria for evaluating of a assets depreciation and accounting parameters of the assets depreciation. In the second part of the paper will be presented depreciation methods as linear, diminishing and accelerating with the tax implications

AUTOMATIC RECOGNITION OF DENTAL PATHOLOGIES AS PART OF A CLINICAL DECISION SUPPORT PLATFORM

The current work is done within the context of Romanian National Program II (PNII) research project "Application for Using Image Data Mining and 3D Modeling in Dental Screening" (AIMMS). The AIMMS project aims to design a program that can detect anatomical information and possible pathological formations from a collection of digital imaging and communications in medicine (DICOM) images. The main function of the AIMMS platform is to provide the user with the opportunity to use an integrated dental support platform, using image processing techniques and 3D modeling. From the literature review, it can be found that for the detection and classification of teeth and dental pathologies existing studies are in their infancy. Therefore, the work reported in this article makes a scientific contribution in this field. In this article it is presented the relevant literature review and algorithms that were created for detection of dental pathologies in the context of research project AIMMS

Utilizarea panelurilor de consumatori in cercetarea de marketing

In legatura cu aplicarea unor metode indirecte de cercetare stiintifica a pietei, in general, precum si referitor la utilizarea unor metode directe, in literatura de specialitate se gasesc numeroase detalii, astfel incat, neconstituind scopul nostru, nu vom starui asupra prezentarii lor. Cu toate acestea, intrucat folosirea unor metode directe de investigare este, de regula, relativ laborioasa si caracteristica unor organisme specializate, consideram utile cateva consideratii teoretice si practice privind modalitatea calitativ superioara de investigare a comportamentului consumatorului prin intermediul sondajului statistic. Este vorba de conceperea, organizarea si exploatarea cercetarilor de tip panel, a caror aplicabilitate constituie in prezent o conditie sine-qua-non a lucrarilor de investigare riguros stiintifica a comportamentului consumatorului, indeosebi prin posibilitatile pe care le ofera pe plan predictiv – latura agreata cu predilectie de factorii de decizie.cercetari de marketing, analiza cantitativa, panel de consumatori, managementul cercetarii

Modelling of the Flow and Deformation Fields at the Profiles Rolling by Field Lines Method

This paper presents a method for modeling of the rolling process based at the deformable continuous medium mechanics, the theory of field lines. The rolling of the profiles and plates may be evaluated as the plane strain state process. Using the equations of the continuous medium and the initial conditions and the limits conditions we solved the speed field, the strain rate field, the strain field. Applying an adequate computation program we obtained the values of the field factors of modeling process. The results are showed into this paper

Experimental Results at Modeling of the Flow and Deformation Fields at the Profiles Rolling

This paper presents the results for modeling of the rolling process based at the deformable continuous medium mechanics, the theory of field lines. The rolling of the profiles and plates may be evaluated as the plane strain state process. Using the equations of the continuous medium and the initial conditions and the limits conditions we solved the speed field, the strain rate field, the strain field. Applying an adequate computation program we obtained the values of the field factors of modeling process. The results are showed into this paper

A Good Earthquake Concave Behaviour of a Seismic Isolator Which Supports a Metallic Roof

We combine some important theoretical mathematical results with practical aspects from engineering in a nice framework of K-spiders, which forms a space with global nonpositive curvature. Some concavity properties into such framework are derived. As an application, we consider a mathematical model for an engineering problem. More precisely, we are trying to model the behaviour of tension forces appearing in a metallic roof supported on seismic isolators. In fact, we are looking to find the properties of good seismic isolators in order to reduce the destructive power of an earthquake. The answer consists of a concave behaviour in terms of the displacements on the 3D axes of the Cartesian system