6,064 research outputs found
1.25 mm Observations of a Complete Sample of IRAS Galaxies: (II) Dust Properties
We present 1.25 mm continuum data for a southern galaxy sample selected from
the IRAS PSC and complete to S_60=2 Jy. Two thirds of the galaxies have been
detected and significant limits on the remaining objects have been set. We
find, on a statistical basis, indications that the dust emission in these
galaxies is somewhat more centrally concentrated than that of the optical
light, possibly tracing a higher metal content in the inner galactic regions.
This result also allows to estimate the aperture corrections to the millimetric
data. The latter, together with IRAS photometric data, have been used to
compare the broad-band FIR/mm spectra with a simple dust model. According to
their far-IR/mm spectrum, the sample galaxies show a dichothomy: almost half of
the objects, those displaying bright 25-60um fluxes ascribed to warm dust
residing in 'starburst' regions, are characterized by higher values of the
bolometric (optical + FIR) luminosity, of the dust-to-gas mass ratio, of the
dust optical depths and of the overall extinction. A complementary class of
objects dominated by cold dust ('cirrus') shows opposite trends. Because of the
favourable observational setup, selection wavelength and completeness, we
believe these data provide an exhaustive and unbiased view of dust properties
in spiral galaxies.Comment: 9 pg Latex file (using mn.sty) gzip'd tar'd file including 7 ps
figures and 3 tables. to appear in MNRA
MM Observations of IRAS Galaxies: Dust Properties, Luminosity Functions and Contributions to the Sub-MM Background
We have studied the FIR/{\it mm} spectrum of IR galaxies by combining IRAS
photometry with new {\it mm} data on a complete southern IRAS galaxy sample.
The observed spectra and a dust model emphasize a dicothomy in the galaxy
population: half of the objects with a lot of warm dust are characterized by
higher values of the bolometric (UV-FIR) luminosity, of the dust-to-gas mass
ratio, of the dust optical depths and extinction, while those dominated by cold
({\it cirrus}) dust show opposite trends. From these data we derive the {\it
mm} luminosity function of galaxies and estimate their contribution to the
sub-{\it mm} background (BKG).Comment: 4 pg Latex file (using included crckapb.sty) gzip'd tar'd file
including 3 ps figures. Proceedings of 'Cold dust Morphology Conference',
Johannesburg, South Africa, January 21-26 1996 A wrong figure is replace
Publication and patent analysis of European researchers in the field of production technology and manufacturing systems
This paper develops a structured comparison among a sample of European researchers in the field of Production Technology and Manufacturing Systems, on the basis of scientific publications and patents. Researchers are evaluated and compared by a variegated set of indicators concerning (1) the output of individual researchers and (2) that of groups of researchers from the same country. While not claiming to be exhaustive, the results of this preliminary study provide a rough indication of the publishing and patenting activity of researchers in the field of interest, identifying (dis)similarities between different countries. Of particular interest is a proposal for aggregating analysis results by means of maps based on publication and patent indicators. A large amount of empirical data are presented and discusse
Outsourcing: guidelines for a structured approach
Outsourcing is a management approach by which an organization delegates some noncore functions to specialized and efÂźcient service providers. In the era of ÂȘglobal marketÂș and ÂȘe-economyÂș, outsourcing is one of the main pillars of the new way to conceive the relationships among companies. Despite outsourcing large diffusion, huge business cases and big deals of documentation available on network or press, there is no structured procedure able to support the govern of the evolution of a generic outsourcing process. In accordance with the principles of total quality management, this paper describes a proposal of a new approach for managing outsourcing processes. The model, which can be easily adapted to different application Âźelds, has been conceived with the main aim of managing strategic decisions, economic factors and human resources. The approach is supported by different decision and analysis tools, such as benchmarking techniques, multiple criteria decision aiding (MCDA) methods, cost analysis, and other process-planning methodologies. An application of the method to a real case is also provide
The Compact Linear ee Collider (CLIC): Physics Potential
The Compact Linear Collider, CLIC, is a proposed ee collider at the
TeV scale whose physics potential ranges from high-precision measurements to
extensive direct sensitivity to physics beyond the Standard Model. This
document summarises the physics potential of CLIC, obtained in detailed
studies, many based on full simulation of the CLIC detector. CLIC covers one
order of magnitude of centre-of-mass energies from 350 GeV to 3 TeV, giving
access to large event samples for a variety of SM processes, many of them for
the first time in ee collisions or for the first time at all. The high
collision energy combined with the large luminosity and clean environment of
the ee collisions enables the measurement of the properties of Standard
Model particles, such as the Higgs boson and the top quark, with unparalleled
precision. CLIC might also discover indirect effects of very heavy new physics
by probing the parameters of the Standard Model Effective Field Theory with an
unprecedented level of precision. The direct and indirect reach of CLIC to
physics beyond the Standard Model significantly exceeds that of the HL-LHC.
This includes new particles detected in challenging non-standard signatures.
With this physics programme, CLIC will decisively advance our knowledge
relating to the open questions of particle physics.Comment: Input to the European Particle Physics Strategy Update on behalf of
the CLIC and CLICdp Collaboration
Battery choice and management for New Generation Electric Vehicles
Different types of electric vehicles (EVs) have been recently designed with the aim of solving pollution problems caused by the emission of gasoline-powered engines. Environmental problems promote the adoption of new-generation electric vehicles for urban transportation. As it is well known, one of the weakest points of electric vehicles is the battery system. Vehicle autonomy and, therefore, accurate detection of battery state of charge (SoC) together with battery expected life, i.e., battery state of health, are among the major drawbacks that prevent the introduction of electric vehicles in the consumer market. The electric scooter may provide the most feasible opportunity among EVs. They may be a replacement product for the primary-use vehicle, especially in Europe and Asia, provided that drive performance, safety, and cost issues are similar to actual engine scooters. The battery system choice is a crucial item, and thanks to an increasing emphasis on vehicle range and performance, the Li-ion battery could become a viable candidate. This paper deals with the design of a battery pack based on Li-ion technology for a prototype electric scooter with high performance and autonomy. The adopted battery system is composed of a suitable number of cells series connected, featuring a high voltage level. Therefore, cell equalization and monitoring need to be provided. Due to manufacturing asymmetries, charge and discharge cycles lead to cell unbalancing, reducing battery capacity and, depending on cell type, causing safety troubles or strongly limiting the storage capacity of the full pack. No solution is available on the market at a cheap price, because of the required voltage level and performance, therefore, a dedicated battery management system was designed, that also includes a battery SoC monitoring. The proposed solution features a high capability of energy storing in braking conditions, charge equalization, overvoltage and undervoltage protection and, obviously, SoC information in order to optimize autonomy instead of performance or vice-versa
Combining Physical galaxy models with radio observations to constrain the SFRs of high-z dusty star forming galaxies
We complement our previous analysis of a sample of z~1-2 luminous and
ultra-luminous infrared galaxies ((U)LIRGs), by adding deep VLA radio
observations at 1.4 GHz to a large data-set from the far-UV to the sub-mm,
including Spitzer and Herschel data. Given the relatively small number of
(U)LIRGs in our sample with high S/N radio data, and to extend our study to a
different family of galaxies, we also include 6 well sampled near IR-selected
BzK galaxies at z~1.5. From our analysis based on the radiative transfer
spectral synthesis code GRASIL, we find that, while the IR luminosity may be a
biased tracer of the star formation rate (SFR) depending on the age of stars
dominating the dust heating, the inclusion of the radio flux offers
significantly tighter constraints on SFR. Our predicted SFRs are in good
agreement with the estimates based on rest-frame radio luminosity and the Bell
(2003) calibration. The extensive spectro-photometric coverage of our sample
allows us to set important constraints on the SF history of individual objects.
For essentially all galaxies we find evidence for a rather continuous SFR and a
peak epoch of SF preceding that of the observation by a few Gyrs. This seems to
correspond to a formation redshift of z~5-6. We finally show that our physical
analysis may affect the interpretation of the SFR-M* diagram, by possibly
shifting, with respect to previous works, the position of the most dust
obscured objects to higher M* and lower SFRs.Comment: 26 pages, 15 figures, 3 tables, accepted for publication in MNRAS on
Dec. 4th, 201
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