Each optical component of the interferometric gravitational wave detector VIRGO is suspended from a cascade of mechanical filters designed to suppress the transmission of seismic vibrations. Each ...mechanical filter supports the weight of the filters below it by means of a set of steel cantilever blade springs. The stress from the load acting on the blades was found to induce a drooping of the blade tips of several microns per day due to a series of microscopic yielding events (micro-creep). This process induces a mechanical displacement shot-noise on the optical component which can dominate the small displacements produced by gravitational waves. The use of a special precipitation hardened steel (Maraging C250), instead of common spring steel, allows the construction of blades that show an acceptable stability under stress.
Craft beer is an authentic product characterised by unique sensory features that distinguish it from industrially produced beers. The typical consumer also closely associates craft beers with the ...concept of traditional products, also in terms of consumption habits and the manner in which they are packaged. In this research, 482 beer consumers were interviewed face-to-face using a paper questionnaire during the Oktoberfest (Piedmont-Northwest Italy), a traditional beer festival that draws thousands of craft beer fans. Two consumer samples were defined on the basis of individual statements regarding their preferred method of beer packaging: The “traditional” consumer, loyal to the conventional beer packaging material (glass bottle) and the “innovative” consumer more inclined to packaging innovation (the use of aluminium cans). The preference scores towards beer attributes of the two identified samples were assessed using a 5-points Likert scale. In addition, the individual socio-demographic characteristics, together with craft beer consumption habits were recorded during the data collection phase. Significant differences between the two consumer samples were found using a non-parametric test; the Mann-Whitney Wilcoxon. In particular, traditional and innovative consumer groups expressed different preference levels towards beer clarity, colour, bitterness and body. For both samples, taste intensity resulted as the top attribute for beer evaluation, highlighting that, even when canned, the consumer is able to evaluate and appreciate the aromatic and quality characteristics of the product. Therefore, although glass remains the preferred packaging material for craft beer consumers, given the increasing acceptance of canned packaging by the traditional consumer, brewers could conceivably focus on canned product lines in order to exploit the inherent logistical and marketing advantages (i.e. graphical communications).
Deep inelastic electron-photon scattering is studied in the $Q^2$ range from 1.2 to 30 GeV$^2$ using the LEP1 data taken with the ALEPH, L3 and OPAL detectors at centre-of-mass energies close to the ...mass of the Z boson. Distributions of the measured hadronic final state are corrected to the hadron level and compared to the predictions of the HERWIG and PHOJET Monte Carlo models. For large regions in most of the distributions studied the results of the different experiments agree with one another. However, significant differences are found between the data and the models. Therefore the combined LEP data serve as an important input to improve on the Monte Carlo models.
Marval 18 is a precipitation hardened steel with particularly high hardness and low creep, presently used for constructing parts of the interferometers for the detection of gravitational waves in the ...experiments VIRGO and LIGO. The elastic moduli have been measured in samples subjected to the same treatments as the parts of the interferometer VIRGO. In addition, the anelastic spectra of samples subjected to different thermal treatments have been measured between 50 and 350 K. It is found that, in the absence of plastic deformation, the elastic energy loss coefficient under flexural vibrations around 1 kHz can vary by more than one order of magnitude depending on the thermal treatments, and is dominated by the thermoelastic effect. The main reason for such strong variations is supposed to be the dependence of the thermal conductivity on the average sizes and distances between the precipitate particles.
In this Report, QCD results obtained from a study of hadronic event structure in high energy
e
+
e
-
interactions with the
L3 detector are presented. The operation of the
LEP collider at many ...different collision energies from 91 to 209
GeV offers a unique opportunity to test QCD by measuring the energy dependence of different observables. The main results concern the measurement of the strong coupling constant,
α
s
, from hadronic event shapes and the study of effects of soft gluon coherence in charged particle multiplicity and momentum distributions.
Fresh-cut salads are ready-to-eat foodstuffs with a growing market share and increasingly popular with consumers. However, a significant part of public opinion considers that bagged salad production ...processes have an effect on sustainability. In parallel, fresh-cut salads producers implement high resources and innovation strategies to improve the production process and product sustainability, highlighting an increasing awareness of their responsibility. The objective of this study was to investigate whether a correspondence exists between consumer preferences and the fresh-cut salad sustainability attributes (environmental, economic and social), indicated by producers (on their packaging and/or company website). Consumer preference analysis of 12 attributes of fresh-cut salads was made using the Best-Worst scaling methodology. Among the selected attributes, 9 were related to sustainability issues and 3 to the intrinsic product characteristics. A paper questionnaire was developed and submitted directly to consumers (n = 216), at different points of sale of several large retail chains in the Turin metropolitan area (Northwest Italy). The analysis of the results highlights that no direct correspondence can be found between the companies’ communications regarding sustainability and the real interest of consumers of fresh-cut salads towards these attributes. Moreover, in contrast to the growing ‘green’ attitude among consumers, the lack of consumer interest in the attributes of environmental sustainability underlines the need to increase consumer awareness of the issue. Thus, this research could contribute to the development of more targeted and accessible communication strategies towards consumers.
The measurement of the finesse and the longitudinal locking of a 100 μm long plane mirrors Fabry-Perot cavity is described. a finesse of up to 5400 has been found. If attached to the Virgo antenna ...suspension (SA), a similar device is sensitive enough to detect the thermal displacement noise of the SA test mass, which is expected to limit the Virgo antenna sensitivity between 10 and 600 Hz. Reducing the Virgo noise floor is a challenge for future antenna development, as this region is the most promising one for coalescing binary stars and pulsar signals.
Single- and multi-photon events with missing energy are selected in 619 pb−1 of data collected by the L3 detector at LEP at centre-of-mass energies between 189 and 209 GeV. The cross sections of the ...process e+e−→νν̄γ(γ) are found to be in agreement with the Standard Model expectations, and the number of light neutrino species is determined, including lower energy data, to be Nν=2.98±0.05±0.04. Selection results are given in the form of tables which can be used to test future models involving single- and multi-photon signatures at LEP. These final states are also predicted by models with large extra dimensions and by several supersymmetric models. No evidence for such models is found. Among others, lower limits between 1.5 and 0.65 TeV are set, at 95% confidence level, on the new scale of gravity for the number of extra dimensions between 2 and 6.
An ultralow resonant frequency vertical seismic activity attenuation filter prototype has been designed and built as the vertical component of a Pre-Isolation Stage (PIS) for low-frequency Seismic ...Attenuation (SA) chains. The task of the PIS is to reduce the excitation of the chain payload's resonant residual motions. A characterization and the performance of the prototype are reported along with some design considerations. An attenuation of 45
dB has been achieved in the region of interest (the SA chain resonant frequency band) and an upgrade to more than 50
dB attenuation is easily achievable. Tests of active feedback loop attenuation driven by electro magnetic actuators and controlled by a Digital Signal Processor reading a precision vertical accelerometer have been successfully performed. The filter also effectively acts as a precision positioner for the suspended payload.
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