Search results for "Measurement"
showing 10 items of 2918 documents
Applying system dynamics modeling to foster a cause-and-effect perspective in dealing with behavioral distortions associated with a city's performanc…
2015
This paper aims to show how applying system dynamics methodology to performance management can provide a powerful modeling perspective enabling public sector organizations to prevent, detect, and counteract behavioral distortions associated with performance measurement. A dynamic performance management approach is able to support performance management system designers in outlining and implementing a consistent set of measures that can allow public sector decision-makers to pursue sustainable organizational learning and development. This perspective implies a major shift from a static to a dynamic picture of organizational processes and results. It means framing delays between causes and ef…
Clinical efficacy of a computerised device (STA™) and a pressure syringe (VarioJect INTRA™) for intraligamentary anaesthesia.
2014
Introduction To evaluate the impact of experience whilst using different devices for intraligamentary anaesthesia, dental students tested clinical anaesthetic efficacy of a mechanical (PDL-S) and a computer-controlled (CCLAD) application system in restorative patients. Material and methods In a prospective study, 41 Patients in need of restorative treatment in lower posterior mandible were randomised into three groups (PDL-S: teeth n = 22; CCLAD: teeth n = 20; inferior alveolar nerve block (IANB): teeth n = 20). Dental last year students conducted anaesthesia and dental treatment. Primary objectives were differences in pain during treatment [numeric rating scale (NRS)] as well as in anaesth…
Reference-Plane Invariant Method for Measuring Electromagnetic Parameters of Materials
2010
This paper presents a simple and effective wideband method for the determination of material properties, such as the complex index of refraction and the complex permittivity and permeability. The method is explicit (non-iterative) and reference-plane invariant: it uses a certain combination of scattering parameters in conjunction with group-velocity data. This technique can be used to characterize both dielectric and magnetic materials. The proposed method is verified experimentally within a frequency range between 2 to 18 GHz on polytetrafluoroethylene and polyvinylchloride samples. A comprehensive error and stability analysis reveals that, similar to other methods based on transmission/re…
Structural and in depth characterization of newly designed conducting/insulating TiN O /TiO2 multilayers obtained by one step LP-MOCVD growth
2001
Abstract TiNxOy/TiO2 multilayers have been grown by LP-MOCVD using titanium isopropoxide (TIP) precursor during the whole growth, but with an ammonia flow interrupted for the TiO2 layers. The one step growth process used to grow these structures allowed to stack the conducting and insulating layers without any growth breakdown. SIMS and TEM analyses showed the presence of an alternated insulating/conducting layers structure. Moreover, electrical measurements allowed to measure the dielectric part of insulating TiO2 stacked in these structures, whose permittivity was found to be about 80 for a MOS structure. Thus, such multilayers may lead to very promising applications in the microelectroni…
Permittivity Measurements of Lossy Liquids at Millimeter-Wave Frequencies
1983
A measurement system is described which allows the determination of the complex permittivity of high-loss liquids at millimeter waves. Basically, the setup consists of a waveguide interferometer whose unknown arm embodies a liquid holder irradiated by an open-ended rectangular waveguide. The sample thickness is varied by means of a piston driven by a micrometer screw. The bridge output then is read as a function of the liquid thickness. Best fitting between experimental and computed data through a suitable model of the system enables the permittivity to be determined. The system can operate, with high sensitivity, over the whole frequency range of the dominant mode propagating in the wavegu…
Machine-learned selection of psychological questionnaire items relevant to the development of persistent pain after breast cancer surgery
2018
Background: Prevention of persistent pain after breast cancer surgery, via early identification of patients at high risk, is a clinical need. Psychological factors are among the most consistently proposed predictive parameters for the development of persistent pain. However, repeated use of long psychological questionnaires in this context may be exhaustive for a patient and inconvenient in everyday clinical practice. Methods: Supervised machine learning was used to create a short form of questionnaires that would provide the same predictive performance of pain persistence as the full questionnaires in a cohort of 1000 women followed up for 3 yr after breast cancer surgery. Machine-learned …
Math homework : Parental help and children’s academic outcomes
2019
In the present study, we examined the longitudinal relations between child-perceived parental help with math homework (i.e., support and control), children's math skills, and mother-reported task persistent behavior in homework situations. A total of 624 mother–child dyads were followed across Grade 6 and Grade 9, controlling for Grade 3 variables. At each measurement point, children completed math tests, and their mothers evaluated task persistence during homework. In Grades 6 and 9, children reported their perceptions of their parents’ help with math homework. First, the results showed that perceived support in Grade 6 predicted an increase in persistence during homework in Grade 9. Secon…
Local hydrogen-clearance and 257-01257-01257-01- measurements in micro-areas of the rat brain
1970
La pression partielle de l'oxygene et la «clearance» de l'hydrogene ont ete mesurees dans des regions circonscrites. Les deux valeurs sont enregistrees par la meme microelectrode de platine (diametre de la pointe 10μ). Cette methode nouvelle est appliquee dans des experiences faites sur le cerveau de Rats narcotises et on est capable d'evaluer les inhomogenites locales de l'apport d'oxygene dependant du flux du sang.
Formation of Layers of Diverse Stoichiometric and Phase Composition in Lithium Tantalate Crystals at Treatment by Vapour Transport Equilibration
2012
Layers from tens to hundreds of microns thick of a different phase composition and stoichiometry are shown to form in lithium tantalate crystals subjected to treatment by vapor transport equilibration in lithium vapour. The 500 microns thick stoichiometric (Li/Ta ≈ 1) layers have ten times lower values of the coercive field compared with congruent lithium tantalate. As electrical measurements suggest, a new polar structure of phase transition at ∼120°C is possibly formed within a thin (30 μm) surface layer of the lithium tantalate sample after vapour transport equilibration treatment.
Low temperature measurements by infrared spectroscopy in $CoFe_2O_4$ ceramic
2012
In this paper results of new far-infrared and middle-infrared measurements (wavenumber range of 4000cm-1 - 100cm-1) in the range of the temperature from 300K to 8K of the CoFe2O4 ceramic are presented. The bands positions and their shapes are the same in the wide temperature range. The quality of the sample was investigated by X-ray, EDS and EPMA studies. The CoFe2O4 reveals the cubic structure (Fd-3m) in the temperature range from 85K to 360 K without any traces of distortion. On the current level of knowledge the polycrystalline CoFe2O4 does not exhibit phase transition in the temperature range from 8 K to 300 K.