Search results for "number"
showing 10 items of 3939 documents
Modeling of the Shear Connection Capacity of Hybrid Steel Trussed Composite Beams
2019
Hybrid Steel Trussed Composite Beams represent a technical solution in use in numerous countries since many years. They are able to join the advantages of prefabrication with those of cast in place structures: they are easy to manufacture, fast to realize, monolithic and with no need of formwork. The behavior of these beams has been recently topic of discussion in the scientific community because the knowledge both related to the reinforced concrete structures and that of composite constructions cannot be straightforwardly extended to this typology, which is intermediate between one and another technology. This paper provides a contribution towards a better understanding of the mechanism of…
Fibre fragment distribution in a single-fibre composite tension test
2001
Abstract Single fibre fragmentation tests are performed for brittle fibres with Weibull strength distribution and different surface treatments. The fragmentation process is modelled and closed-form expressions for break spacing distribution are obtained. The model accounts for the effect of finite fibre length on the initial fragmentation as well as for break interaction on the advanced fragmentation stage. It is assumed that the exclusion zone due to fibre–matrix interface failure and stress recovery in the fibre is linearly dependent on the applied load. This assumption is validated experimentally. The derived theoretical average fragment length dependence on applied load is used to deter…
Assessing the profitability of investment projects using ordered fuzzy numbers
2019
Wstęp: U podstaw rozważań leży stwierdzenie, że większość podejść do budżetowania kapitałowego ma charakter deterministyczny. W rzeczywistości problemowi budżetowania towarzyszy niepewność i ryzyko związane z przetwarzaniem nieprecyzyjnych danych. Uwzględnienie tej niepewności nie tylko pomaga lepiej zmierzyć efektywność projektów inwestycyjnych, ale także rozszerzyć zastosowanie metod budżetowania kapitałowego w warunkach rzeczywistych lub niepewnych. Głównym celem artykułu jest opracowanie nowatorskiego podejścia do oceny opłacalności projektu inwestycyjnego w warunkach niepewności. Metody: Prezentujemy nowatorskie podejście uwzględniające niepewność w ocenie opłacalności projektów inwest…
Podejście do analizy zaangażowania interesariuszy w projekcie wykorzystujące skierowane liczby rozmyte
2016
Celem artykułu jest przedstawienie autorskiego podejścia do zagadnienia szacowania zaangażowania interesariuszy w projekcie. W pracy zaprezentowano możliwości zastosowania aparatu matematycznego w postaci skierowanych liczb rozmytych do opisu parametrów oceny ich dynamiki zmian w cyklu życia projektu.
Charge radius changes of even-even neutron-rich Tellurium isotopes
2005
Laser spectroscopy based on resonant ionization of laser-desorbed atoms has been used to study the neutron-rich tellurium isotopes with the COMPLIS facility at ISOLDE-CERN. The isotope shift and the hyperfine structure of several neutron-rich Te isotopes: $^{120–136}$Te and $^{123m–133m}$Te have been measured. From the hyperfine structure and the isotope shift we can extract the magnetic and quadrupole moments and the change in the mean square charge radius respectively. The mean square charge radii of the even-even isotopes have been deduced and their comparison with the known data for the other elements near Z=50 is presented. The experimental $\delta$ is compared with that obtained from …
Toxicity of Dental Amalgams vs Composite Resins
2016
Ideal qualities of dental materials should include, in terms of biocompatibility, passivity towards oral tissues, so the material should not contain any leachable toxic and diffusible substances, neither release any harmful substance that can cause in time side effects, locally or generally. Even if amalgams are a group of dental materials with a long recorded history, many practitioners blame them, in contradiction with composite resins, especially for releasing free mercury into the body. On the other side, composite resins have reached great biocompatibility specifications, but also have many qualities that need more research, especially long term type.
Influence of the Resin Layer Thickness at the Interface of Hybrid Metal-composite Co-cured Joints
2011
As discussed in literature, the accurate analysis of the modern co-cured joints between composite materials or between a metal and a composite material (hybrid joints) is complicated by the influence of the interface resin layer on the interface singular stress field. In such joints, in fact, there is not a proper adhesive layer and the thickness of the resin layer, that plays the role of the adhesive, is not constant due to the presence of the reinforcing fibers in the composite adherent. For this reason several authors assume that a generic co-cured joint can not be studied as a simple bi-material joint, without considering the particular characteristics of the actual resin layer. This pr…
Stress in emergency telephone number operators during the COVID-19 pandemic: the role of self-efficacy and Big Five personality traits
2022
BackgroundEmergency telephone number operators experience many challenges in their work during the COVID-19 pandemic. Their personality traits and self-efficacy may act as important factors in their level of perceived stress. The aim of this study was to determine the relationship between Big Five personality traits, self-efficacy and perceived stress among emergency tele-phone number operators during the COVID-19 pandemic.Participants and procedureOne hundred emergency telephone number operators participated in the study. The Perceived Stress Scale (PSS-10), Ten Item Personality Inventory (TIPI) and Generalized Self Efficacy Scale (GSES) were used.ResultsEmergency telephone number operator…
Discussing Mathematical Learning and Mathematical Praxeologies from a Subject Scientific Perspective
2018
International audience; This programmatic contribution discusses the link between concepts from Anthropological Theory of Didactics (ATD) and the “subject-scientific point of view” according to Holzkamp (1985, 1993). The main common concern of ATD and the subject-scientific approach is to conceptualize and analyse “objects” like “institutionalized mathematical knowledge” and “university” not as conditions that cause reactions but essentially as meanings in the sense of generalized societal reified action possibilities. The link of both approaches is illustrated by the issue of “real numbers” in the transition from school to university: Hypotheses are derived for further actual-empirical res…
In situ measurements of background aerosol and subvisible cirrus in the tropical tropopause region
2002
[1] In situ aerosol measurements were performed in the Indian Ocean Intertropical Convergence Zone (ITCZ) region during the Airborne Polar Experiment-Third European Stratospheric Experiment on Ozone (APE-THESEO) field campaign based in Mahe, Seychelles between 24 February and 6 March 1999. These are measurements of particle size distributions with a laser optical particle counter of the Forward Scattering Spectrometer Probe (FSSP)-300 type operated on the Russian M-55 high-altitude research aircraft Geophysica in the tropical upper troposphere and lower stratosphere up to altitudes of 21 km. On 24 and 27 February 1999, ultrathin layers of cirrus clouds were penetrated by Geophysica directly…