Search results for "character"
showing 10 items of 2956 documents
Wooden Surface Investigation: an Optical Approach Based on Shadow Moiré
2007
The interest in the mechanical behaviour of wood is a very important task due to the increasing role played by wood structures in modern architecture as well as its applicability in restoration of ancient buildings. The behaviour of wooden surfaces experiencing variable humidity conditions is of great importance both with concern to performances of wooden building’s structures and to ensure correct restoration and conservation of art works like wooden sculptures and panel paintings [1]. In literature there are only a few studies dealing with the influence of moisture on the physical properties of wood [1,2]. The characterization of wooden behaviour related to changes in the humidity level c…
The Ambivalence of Revenge and of the Avenger's Role in HAMLET: The Function of Letters and Emblematic Allusions
2011
Electro Thermo Mechanical Characterization of NiTi Actuator Wire
2010
A smeared seismicity constitutive model
2004
The classical application of rate and state dependent frictional constitutive laws has involved the instabilities developed between two sliding surfaces. In such a situation, the behaviour and evolution of asperities is the controlling mechanism of velocity weakening. However, most faults have a substantial thickness and it would appear that it is the bulk behaviour of the fault gouge, at whatever scale, that is important. The purpose of this paper is to explore how bulk frictional sliding behaviour may be described. We explore here the consequences of applying the rate and state framework initially developed to describe the frictional behaviour at the interface between two interacting slid…
Shock formation in the dispersionless Kadomtsev-Petviashvili equation
2016
The dispersionless Kadomtsev-Petviashvili (dKP) equation $(u_t+uu_x)_x=u_{yy}$ is one of the simplest nonlinear wave equations describing two-dimensional shocks. To solve the dKP equation we use a coordinate transformation inspired by the method of characteristics for the one-dimensional Hopf equation $u_t+uu_x=0$. We show numerically that the solutions to the transformed equation do not develop shocks. This permits us to extend the dKP solution as the graph of a multivalued function beyond the critical time when the gradients blow up. This overturned solution is multivalued in a lip shape region in the $(x,y)$ plane, where the solution of the dKP equation exists in a weak sense only, and a…
GaN and SiC Device Characterization by a Dedicated Embedded Measurement System
2023
This work proposes a comparison among GaN and SiC device main parameters measured with a dedicated and low-cost embedded system, employing an STM32 microcontroller designed to the purpose. The system has the advantage to avoid the use of expensive laboratory measurement equipment to test the devices, allowing to obtain their behavior in operating conditions. The following KPIs (Key Performance Indicators) are measured and critically compared: threshold voltage, on-resistance and input capacitance. All the measurements are carried out in a short time interval and on a wide range of switching frequencies, ranging from 10 kHz to 1 MHz. This investigation is focused on the deviation of the figu…
Cornicioni e sistemi di smaltimento delle acque meteoriche nell’architettura tradizionale mediterranea. Conoscenza, durabilità e recupero compatibile…
2020
The essay explores the construction aspects of cornices that, from elements of protection, they can also become elements of degradation and instability due to their shape. We would analyze formal and material values of a cornice: it presents complex characters and summarizes problems deriving from construction requirements of building envelope, due to the double value of ornamentation (crowning of building) and functional component (removal system of meteoric water from façade). This study suggests a repertoire of “rules of art”: deriving from treatises and manuals and constituting points of reference for historical construction. We would indicate the main degradations that the shape of cor…
On the experimental validation of an improved five-parameter model for silicon photovoltaic modules
2012
Abstract This paper presents the experimental validation of a new five-parameter model capable of analytically describing the I–V characteristic of a silicon photovoltaic module for each generic condition of operative temperature and solar irradiance. The operating current calculated with the model was validated on the basis of a series of experimental measurements performed in the field on two commercial silicon photovoltaic panels connected to a set of nine constant values of the electrical load. In order to examine the panels working in almost steady-state conditions only the data-sets of the sunniest days from sunrise to sunset were used. Unfortunately the production spread of photovolt…
Synthesis and reactivity of .sigma.-bonded silicon metalloporphyrins. Spectroscopic characterization and electrochemistry of (P)Si(R)2, (P)Si(R)X, an…
1988
Surface AFM microscopy of unworn and worn samples of silicone hydrogel contact lenses
2008
Abstract: Purpose. To evaluate the qualitative and quantitative topographic changes in the surface of worn contact lenses (CLs) of different materials using atomic force microscopy (AFM). Methods. The topography of five different CL materials was evaluated withAFM over a surface of 25 lm2 according to previously published experimental setup. Average roughness (Ra) and root mean square (Rms) values were obtained for unworn and worn samples. Results. The Ra value increased for balafilcon A (11.62–13.68 nm for unworn and worn samples, respectively), lotrafilcon A (3.67–15.01 nm for unworn and worn samples, respectively), lotrafilcon B (4.08–8.42 nm for unworn and worn samples, respectively), g…