Pub Date : 2015-11-12DOI: 10.1109/RTSI.2015.7325087
C. D. Santi, M. D. Lago, M. Buffolo, M. Meneghini, G. Meneghesso, E. Zanoni
This paper describes one of the first studies of the degradation of retrofit light bulbs based on white GaN light emitting diodes. The results indicate that the lifetime of LED lamps depends mostly on the stability of the driver and optical elements, rather than on the degradation of the LED chips, that have a stable output over stress time. By comparing lamps from four different manufacturers stressed at room and high temperature, we found that (i) long-term stress causes a change of the chromatic properties of the lamps, which is ascribed to the degradation of the phosphors or to the inner LED reflector; (ii) during ageing the LED driver may degrade gradually and/or catastrophically, causing a reduction of the output optical power, or a complete failure; (iii) proper thermal management and heat dissipation reduce the degradation rate; (iv) spectral transmissivity measurements and visual inspection reveal the degradation of the diffusive optical elements, which is induced by the short wavelength side of the LED emission spectrum.
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Pub Date : 1900-01-01DOI: 10.1109/RTSI.2015.7325133
M. Cheminod, L. Durante, Marcello Maggiora, L. Seno, Carmela Troilo, A. Valenzano
The modeling and analysis of security properties in large and complex networked systems is more and more demanding for the availability of computer-assisted software tools able to help designers and engineers in describing and verifying their systems in an easy way. Indeed, on the one hand these tasks are usually cumbersome and error-prone when carried out manually, while on the other hand they have to be repeated during the whole system lifetime, starting with its conception and deployment and ending with the system final disposal. This paper presents a semi-automated framework which is conceived for the fine-grained description of networked systems from the security point of view. In particular, the paper shows how a simple graphical user interface allows the designer to largely ignore the syntax of the input language for the analysis tool and focus only on the implemented system characteristics.
{"title":"A semi-graphical modeling framework for the automated analysis of networked systems security","authors":"M. Cheminod, L. Durante, Marcello Maggiora, L. Seno, Carmela Troilo, A. Valenzano","doi":"10.1109/RTSI.2015.7325133","DOIUrl":"https://doi.org/10.1109/RTSI.2015.7325133","url":null,"abstract":"The modeling and analysis of security properties in large and complex networked systems is more and more demanding for the availability of computer-assisted software tools able to help designers and engineers in describing and verifying their systems in an easy way. Indeed, on the one hand these tasks are usually cumbersome and error-prone when carried out manually, while on the other hand they have to be repeated during the whole system lifetime, starting with its conception and deployment and ending with the system final disposal. This paper presents a semi-automated framework which is conceived for the fine-grained description of networked systems from the security point of view. In particular, the paper shows how a simple graphical user interface allows the designer to largely ignore the syntax of the input language for the analysis tool and focus only on the implemented system characteristics.","PeriodicalId":294825,"journal":{"name":"International Forum on Research and Technologies for Society and Industry Leveraging a better tomorrow","volume":"44 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114627443","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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