Thermal control of transparent elements onboard artificial satellites

Temperature control of transparent elements onboard artificial satellite

“Epiphanic” peripheries, re-appropriation of the city and dwelling quality. Periferie epifaniche, riappropriazione della città e qualità dell’abitare

Le periferie, e soprattutto quelle romane, sono spesso associate all’idea del degrado. In realtà, la realtà delle periferie è molto più complessa. In primo luogo esistono molte situazioni diverse di periferia. Inoltre è superata la semplice dicotomia centro-periferia e l’idea di Roma come un centro storico circondato da una corona di periferie degradate. Ancor più bisogna discutere l’idea stessa di degrado e la sua associazione automatica alle periferie. Le periferie sono luoghi molto vitali, ricchi di iniziative e di protagonismo sociale, dove il senso di appartenenza può essere molto forte, così come le progettualità e le capacità di autorganizzazione. Sono, allo stesso tempo, laboratori sociali della convivenza e luoghi di produzione culturale. La qualità dell’abitare è qui associata alla qualità delle relazioni sociali. I problemi e i conflitti però non mancano, spesso associati ad una assenza delle istituzioni e della politica. Non bisogna quindi cadere in un “romanticismo” della periferia, quanto lavorare per una valorizzazione delle energie sociali, delle progettualità locali e del protagonismo degli abitanti al fine di superare i grandi problemi ancora esistenti. Questo pone compiti impegnativi all’urbanistica ed un suo ripensamento

Distribution Free Estimation of Spatial Autoregressive Binary Choice Panel Data Models

This paper proposes a semiparametric estimator for spatial autoregressive (SAR) binary choice models in the context of panel data with fixed effects. The estimation procedure is based on the observational equivalence between distribution free models with a conditional median restriction and parametric models (such as Logit/Probit) exhibiting (multiplicative) heteroskedasticity and autocorrelation. Without imposing any parametric structure on the error terms, we consider the semiparametric nonlinear least squares (NLLS) estimator for this model and analyze its asymptotic properties under spatial near-epoch dependence. The main advantage of our method over the existing estimators is that it consistently estimates choice probabilities. The finite-dimensional estimator is shown to be consistent and root-n asymptotically normal under some reasonable conditions. Finally, a Monte Carlo study indicates that the estimator performs quite well in finite samples

Electron cloud and ion effects

The significant progress in the understanding and control of machine impedances has allowed obtaining beams with increasing brilliance. Dense positively charged beams generate electron clouds via gas ionization, photoemission and multipacting. The electron cloud in turn interacts with the beam and the surrounding environment originating fast coupled and single bunch instabilities, emittance blow-up, additional loads to vacuum and cryogenic systems, perturbation to beam diagnostics and feedbacks and it constitutes a serious limitation to machine performance. In a similar way high brilliance electron beams are mainly affected by positively charged ions produced by residual gas ionization. Recent observations of electron cloud build-up and its effects in present accelerators are reviewed and compared with theory and with the results of state-of-the-art computer simulations. Two-stream instabilities induced by the interaction between electron beams and ions are discussed. The implications for future accelerators and possible cures are addressed [1]

Intensity (and brightness) limitations in the LHC proton injectors

The presently known intensity and brightness limitations in the LHC Proton Injectors are reviewed and the possible cures are outlined

Ultimate LHC beam

The present status of the nominal LHC beam in the LHC injector complex and the limitations towards the achievement of the ultimate brightness are outlined

What do we know from the literature on public e-services?.

Public e-services are a broad and growing research field in which scholars and practitioners from different domains are involved. However, the increasing attention devoted to public e-services only partially captures the extreme variety of aspects and implications of the diffusion of information and communication technologies at all levels of public administrations. The paper aims to develop a meta-analysis of the literature on the delivery, diffusion, adoption and impact of public e-services and examines current research trends in terms of differences in methodologies, approaches and key indicators across five service platforms: eGovernment, eEducation, eHealth, Infomobility and eProcurement. We examined 751 articles appeared in 2000-2010 in the top international academic journals listed in the Social Science Citation Index (SSCI) of the Institute for Scientific Information (ISI), as classified in the following fields: Communication, Economics, Education, Environmental Studies, Geography, Health Policy & Services, Information Science & Library Science, Law, Management, Planning & Development, Public Administration, Transportation and Urban Studies. We highlight a significant heterogeneity in scientific production across service domains, countries covered by empirical analyses, indicators used, and affiliation of authors. We also show an increasing diffusion of quantitative methods applied to different research fields which still appears to be constrained by data limitations. The overall picture emerging from the analysis is one characterized by largely unexplored service domains as well as scarcely analyzed issues both across and within individual service platforms (e.g. front vs. back office issues). Thus many research opportunities seem to emerge and need to be exploited from different disciplinary perspectives in this field of analysis.eGovernment, eEducation, eHealth, Infomobility, eProcurement, Bibliometrics, Metaanalysis, Innovation in services, Public e-services

A simulation of remote sensor systems and data processing algorithms for spectral feature classification

A computational model of the deterministic and stochastic processes involved in multispectral remote sensing was designed to evaluate the performance of sensor systems and data processing algorithms for spectral feature classification. Accuracy in distinguishing between categories of surfaces or between specific types is developed as a means to compare sensor systems and data processing algorithms. The model allows studies to be made of the effects of variability of the atmosphere and of surface reflectance, as well as the effects of channel selection and sensor noise. Examples of these effects are shown