Analysis and Test of the Effects of Single Event Upsets Affecting the Configuration Memory of SRAM-based FPGAs

SRAM-based FPGAs are increasingly relevant in a growing number of safety-critical application fields, ranging from automotive to aerospace. These application fields are characterized by a harsh radiation environment that can cause the occurrence of Single Event Upsets (SEUs) in digital devices. These faults have particularly adverse effects on SRAM-based FPGA systems because not only can they temporarily affect the behaviour of the system by changing the contents of flip-flops or memories, but they can also permanently change the functionality implemented by the system itself, by changing the content of the configuration memory. Designing safety-critical applications requires accurate methodologies to evaluate the system’s sensitivity to SEUs as early as possible during the design process. Moreover it is necessary to detect the occurrence of SEUs during the system life-time. To this purpose test patterns should be generated during the design process, and then applied to the inputs of the system during its operation. In this thesis we propose a set of software tools that could be used by designers of SRAM-based FPGA safety-critical applications to assess the sensitivity to SEUs of the system and to generate test patterns for in-service testing. The main feature of these tools is that they implement a model of SEUs affecting the configuration bits controlling the logic and routing resources of an FPGA device that has been demonstrated to be much more accurate than the classical stuck-at and open/short models, that are commonly used in the analysis of faults in digital devices. By keeping this accurate fault model into account, the proposed tools are more accurate than similar academic and commercial tools today available for the analysis of faults in digital circuits, that do not take into account the features of the FPGA technology.. In particular three tools have been designed and developed: (i) ASSESS: Accurate Simulator of SEuS affecting the configuration memory of SRAM-based FPGAs, a simulator of SEUs affecting the configuration memory of an SRAM-based FPGA system for the early assessment of the sensitivity to SEUs; (ii) UA2TPG: Untestability Analyzer and Automatic Test Pattern Generator for SEUs Affecting the Configuration Memory of SRAM-based FPGAs, a static analysis tool for the identification of the untestable SEUs and for the automatic generation of test patterns for in-service testing of the 100% of the testable SEUs; and (iii) GABES: Genetic Algorithm Based Environment for SEU Testing in SRAM-FPGAs, a Genetic Algorithm-based Environment for the generation of an optimized set of test patterns for in-service testing of SEUs. The proposed tools have been applied to some circuits from the ITC’99 benchmark. The results obtained from these experiments have been compared with results obtained by similar experiments in which we considered the stuck-at fault model, instead of the more accurate model for SEUs. From the comparison of these experiments we have been able to verify that the proposed software tools are actually more accurate than similar tools today available. In particular the comparison between results obtained using ASSESS with those obtained by fault injection has shown that the proposed fault simulator has an average error of 0:1% and a maximum error of 0:5%, while using a stuck-at fault simulator the average error with respect of the fault injection experiment has been 15:1% with a maximum error of 56:2%. Similarly the comparison between the results obtained using UA2TPG for the accurate SEU model, with the results obtained for stuck-at faults has shown an average difference of untestability of 7:9% with a maximum of 37:4%. Finally the comparison between fault coverages obtained by test patterns generated for the accurate model of SEUs and the fault coverages obtained by test pattern designed for stuck-at faults, shows that the former detect the 100% of the testable faults, while the latter reach an average fault coverage of 78:9%, with a minimum of 54% and a maximum of 93:16%

A configurable board-level adaptive incremental diagnosis technique based on decision trees

Functional diagnosis for complex electronic boards is a time-consuming task that requires big expertise to the diagnosis engineers. In this paper we propose a new engine for board-level adaptive incremental functional diagnosis based on decision trees. The engine incrementally selects the tests that have to be executed and based on the test outcomes it automatically stops the diagnosis as soon as one or more faulty candidates can be identified, thus allowing to reduce the number of executed tests. Moreover, we propose a configurable early stop condition for the engine that allows to further reduce the number of executed tests leveraging the diagnosis accuracy. The effectiveness of the proposed approach has been assessed using a set of synthetic but realistic boards and three industrial boards

Epstein-barr virus induced cellular changes in nasal mucosa

A 21-year-old man presented with nasal obstruction of the right nasal fossa of 1 year duration. Nasal endoscopy revealed in the right inferior turbinate head a rounded neoplasm about 1 cm in diameter. Cytologic study of a nasal scraping specimen disclosed numerous clusters containing columnar cells with cytomegaly, prominent multinucleation, markedly sparse shortened cilia; the cytoplasm contained an acidophil area and a small round area that stained poorly; cells with a large intracytoplasmic vacuole that was acidophil and PAS+. Serology tests using the nested polymer chain reaction (PCR) technique on serum, nasal and pharyngeal smears revealed an Epstein-Barr virus (EBV) infection that was confirmed at electron microscopy. The clinical and cytological features resolved 19 months after the initial evaluation. CONCLUSION: The authors advise carrying out clinical (endoscopy, serology, etc.) evaluation of all endonasal neoplasms and to routinely perform cytological study on nasal scraping specimens. When samples test positive for EBV, nasal and nasopharyngeal endoscopy should be performed regularly to detect possible evidence for nasopharyngeal carcinoma (NPC)

UA2TPG: An untestability analyzer and test pattern generator for SEUs in the configuration memory of SRAM-based FPGAs

This paper presents UA2TPG, a static analysis tool for the untestability proof and automatic test pattern generation for SEUs in the configuration memory of SRAM-based FPGA systems. The tool is based on the model-checking verification technique. An accurate fault model for both logic components and routing structures is adopted. Experimental results show that many circuits have a significant number of untestable faults, and their detection enables more efficient test pattern generation and on-line testing. The tool is mainly intended to support on-line testing of critical components in FPGA fault-tolerant systems

Palmitoylethanolamide dampens reactive astrogliosis and improves neuronal trophic support in a triple transgenic model of Alzheimer’s disease: in vitro and in vivo evidence

Alzheimer’s disease (AD) is a neurodegenerative disorder responsible for the majority of dementia cases in elderly people. It is widely accepted that the main hallmarks of AD are not only senile plaques and neurofibrillary tangles but also reactive astrogliosis, which often precedes detrimental deposits and neuronal atrophy. Such phenomenon facilitates the regeneration of neural networks; however, under some circumstances, like in AD, reactive astrogliosis is detrimental, depriving neurons of the homeostatic support, thus contributing to neuronal loss. We investigated the presence of reactive astrogliosis in 3×Tg-AD mice and the effects of palmitoylethanolamide (PEA), a well-documented anti-inflammatory molecule, by in vitro and in vivo studies. In vitro results revealed a basal reactive state in primary cortical 3×Tg-AD-derived astrocytes and the ability of PEA to counteract such phenomenon and improve viability of 3×Tg-AD-derived neurons. In vivo observations, performed using ultramicronized- (um-) PEA, a formulation endowed with best bioavailability, confirmed the efficacy of this compound. Moreover, the schedule of treatment, mimicking the clinic use (chronic daily administration), revealed its beneficial pharmacological properties in dampening reactive astrogliosis and promoting the glial neurosupportive function. Collectively, our results encourage further investigation on PEA effects, suggesting it as an alternative or adjunct treatment approach for innovative AD therapy

Poincaré-type inequality for Lipschitz continuous vector fields

open4noG. C. and M. M. are partially supported by MAnET Marie Curie Initial Training Networks (ITN). A. P. was supported by the Progetto CaRiPaRo “Nonlinear Partial Differential Equations: models, analysis, and control-theoretic problems” and now is supported by ERC ADG GeMeThNES n∘ 246923 and GNAMPA of INDAM. F. S.C. is supported by MIUR, Italy, GNAMPA of INDAM, University of Trento and MAnET Marie Curie Initial Training Networks (ITN) n∘ 607643.The scope of this paper is to prove a Poincaré type inequality for a family of nonlinear vector fields, whose coefficients are only Lipschitz continuous with respect to the distance induced by the vector fields themselves.openCitti, Giovanna; Manfredini, Maria; Pinamonti, Andrea; Serra Cassano, FrancescoCitti, Giovanna; Manfredini, Maria; Pinamonti, Andrea; Serra Cassano, Francesc

Acoustic pharyngometry: clinical and instrumental correlations in sleep disorders

Summary Matteo Gelardi 1 , Alessandro Maselli del Giudice 2 , Francesco Cariti 3 , Michele Cassano 4 , Aline Castelante Farras 5 , Maria Luisa Fiorella 6 , Pasquale Cassano 7 1 ENT specialist (Physician of the Bari University Otorhinolaryngology Department - Italy) 2 Physician (ENT Resident - Bari University - Italy) 3 Physician (ENT Resident - Bari University - Italy) 4 ENT specialist (Researcher of the Foggia University Otorhinolaryngology Department - Italy) 5 ENT specialist (Fellow of the Foggia University Otorhinolaryngology Department - Italy) 6 ENT specialist (Researcher of the Bari University Otorhinolaryngology Department - Italy) 7 ENT and Audiology specialist (Head of the Foggia University Otorhinolaryngology Department and Full Professor of Otorhinolaryngology at Foggia University - Italy)Bari University - Italy; Foggia University - ItalyDr. Michele Cassano Via: Crispi 34/C CEP: 70123 Bari - Italy. Telephone: 00xx39-080-5235508/ 00xx39-3388105268 Fax: 00xx39-080-5211318. Dra. Aline Castelante Farras Rua Sete de Setembro, 676 Centro Vila Velha - ES Telefone: 27-32393661 E-mail: [email protected] [email protected] Paper submitted to the ABORL-CCF SGP (Management Publications System) on July 29th, 2005 and accepted for publication on November 3th, 2006. cod. 567

ERA UMA VEZ UMA MENINA QUE NUNCA VIRA O MAR...QUANDO A TRADIÇÃO ORAL SE DEIXA RECRIAR PELA PALAVRA ESCRITA

Pretendemos, neste ensaio, refletir sobre a prática discursiva do conto O beijo da palavrinha, de autoria de Mia Couto. Isso significa dizer que discutiremos a importância do emprego simbólico de determinadas palavras na constituição de um espaço mítico e humano, ao mesmo tempo. Também serão analisadas as imagens de Malangatana que ilustram a obra, importantes na construção do sentido do texto

Bibliotecas públicas no Rio de Janeiro do século XIX: produção dos sentidos de língua, leitura e nação

Estudo das condições em que Biblioteca Nacional e Real Gabinete Português de Leitura se instituíram e discursivisaram durante o período imperial e configuraram-se como espaços enunciativos do português com repercussão no âmbito político. Fontes primárias, tais como regimentos, relatórios, atas e estatutos, constituíram nosso arquivo. Observamos em que medida BN e RGPL contribuíram para que noções como língua e leitura se construíssem e como tais construções afetaram e vêm afetando a formação do sujeito-leitor no país. Os pressupostos da Análise do Discurso francesa (Pêcheux; Orlandi) balizaram nossas análises