Search results for "equivalent"
showing 10 items of 308 documents
Elective partial nephrectomy is equivalent to radical nephrectomy in patients with clinical T1 renal cell carcinoma: results of a retrospective, comp…
2012
Study Type - Therapy (cohort) Level of Evidence 2b What's known on the subject? and What does the study add? Few studies supported the expanded indications for nephron-sparing surgery (NSS) in selected patients with 4.1 cm renal tumours in the size range (T1b). However, all these comparative studies included both imperative and elective partial nephrectomy and patient selection for analysis was based on pathological stage (pT1) and not on clinical stage (cT1). Patients with clinically organ-confined RCC (cT1) who are candidates for elective PN have a limited risk of clinical understaging. NSS is not associated with an increased risk of recurrence and cancer-specific mortality both in cT1a a…
Sensitivity of external resources to cash flow under financial constraints
2014
Abstract This paper explores the external financing–cash flow relationship in capital structure theory by comparing unlisted (financially constrained) and listed (financially unconstrained) companies. We postulate that investment is determined endogenously in the case of unlisted firms, as they are strongly dependent on internally generated funds (cash flow). Consequently, unlisted firms invest their cash flow in profitable projects, using any residual cash flow to increase their holdings of safe assets. In turn, listed companies determine their investment exogenously and may reduce leverage if they raise an excess of cash flow. As a result, listed companies would react more negatively to s…
Definition of diagonal Poisson's ratio and elastic modulus for infill masonry walls
2014
The prediction of the response of infilled frames through the simplified approach of substituting the infill with an equivalent pin-jointed strut is treated. In this framework the results of an experimental study for the mechanical characterization of different types of masonry infills having the aim of estimating strength, Young modulus and Poisson's ratio are presented. Four types of masonry were investigated and subjected to ordinary compressive tests orthogonally to the mortar beds and along the directions of the mortar beds. The experimental campaign confirmed the possibility of using an orthotropic plate model for prediction of the Poisson's ratio and Young modulus along the diagonal …
Infilled frames: developments in the evaluation of the stiffening effect of infills
2003
In order to consider the modified seismic response of framed structures in the presence of masonry infills, proper models have to be formulated. Because of the complexity of the problem, a careful definition of a diagonal pin-jointed strut, able to represent the horizontal force-interstorey displacement cyclic law of the actual infill, may be a solution. In this connection the present paper shows a generalized criterion for the determination of the ideal cross-section of the strut mentioned before. The procedure is based on the equivalence between the lateral stiffness of the actual infilled frame scheme during the conventional elastic stage of the response and the lateral stiffness of the …
Ultrasonic inspection for the detection of debonding in CFRP-reinforced concrete
2017
Fibre-reinforced plastic (FRP) composites are extensively used to retrofit civil structures. However, the quality and the characteristics of the bond between the FRP and the structure are critical to ensure the efficacy of the retrofit. For this reason, effective non-destructive evaluation (NDE) methods are often necessary to assess the bonding conditions. This article presents an ultrasonic technique for detecting defects at the FRP-substrate interface. The technique uses the Akaike Information Criterion, to detect automatically the onset of the ultrasonic signals, and the novel Equivalent Time Lenght (ETL) parameter, to quantify the energy of the propagating ultrasonic signals along the i…
Analysis of the electromagnetic radiation generated by a multipactor discharge occurring within a microwave passive component
2010
International audience; Multipactoring is a non-linear phenomenon that appears in highpower microwave equipments operating under vacuum conditions and causes several undesirable effects. In this manuscript, a theoretical and experimental study of the RF spectrum radiated by a multipactor discharge, occurring within a realistic microwave component based on rectangular waveguides, is reported. The electromagnetic coupling of a multipactor current to the fundamental propagative mode of a uniform waveguide has been analyzed in the context of the microwave network theory. The discharge produced under a single-carrier RF voltage regime has been approached as a shunt current source exciting such a…
Atomic Layer Deposition and Characterization of Erbium Oxide-Doped Zirconium Oxide Thin Films
2010
ZrO 2 films doped with Er 2 O 3 were grown by atomic layer deposition from tris(2,2,6,6-tetramethyl-3,5-heptanedionato)erbium, bis(methylcyclopentadienyl)methoxymethylzirconium, and ozone as precursors at 350°C. The erbium content was 1―5 cation %. The films were uniform in thickness. The ZrO 2 :Er 2 O 3 films were crystallized already in the as-deposited state. Upon annealing at 650°C, they were stabilized in the form of cubic or tetragonal polymorph of ZrO 2 . Enhancement in capacitance required intense crystallization that was observed when the film thickness exceeded 4.4 nm. The permittivity of the ZrO 2 :Er 2 O 3 films could reach 31. The capacitors based on the doped ZrO 2 possessed l…
Anodic growth of passive layers on steel rebars in an alkaline medium simulating the concrete pores
2006
Electrochemical impedance spectroscopy (EIS) and cyclic voltammetry (CV) techniques have been used to study passive layers anodically grown on steel rebars in an aqueous alkaline solution simulating the electrolyte of the concrete pores. Nyquist diagrams recorded by EIS at the different stabilization potentials show a diffusional tail at low frequencies. The analysis of the impedance measurements has been made by means of an equivalent circuit with a Warburg component and within the framework of the point defect model (PDM) theory. It is observed that the calculated concentration of vacancies is a function of the potential in accordance with the theoretical prediction of the PDM.
Series resistance determination and further characterization of c-Si PV modules
2012
Abstract This paper presents a new algorithm for determination of the series resistance of crystalline-Si PV modules from individual illuminated I–V curves. The ideality factor and the reverse saturation current are then extracted in the classic way. The approach is applied to in-situ measured data from modules based on two types of mc-Si feedstock. The results indicate that the method yields physically meaningful parameters. An improved definition of local ideality factor is suggested, resulting in m-V plots unaffected by the series resistance. In addition, m-I plots are introduced for the first time. The novel differential techniques reveal an unexpected rise of the ideality factor at ope…
High voltage vacuum-deposited CH3NH3PbI3-CH3NH3PbI3 tandem solar cells
2018
The recent success of perovskite solar cells is based on two solid pillars: the rapid progress of their power conversion efficiency and their flexibility in terms of optoelectrical properties and processing methods. That versatility makes these devices ideal candidates for multi-junction photovoltaics. We report an optically optimized double junction CH3NH3PbI3–CH3NH3PbI3 tandem solar cell where the matched short-circuit current is maximized while parasitic absorption is minimized. The use of an additive vacuum-deposition protocol allows us to reproduce calculated stack designs, which comprise several charge selective materials that ensure appropriate band alignment and charge recombination…