EDACs and test integration strategies for NAND flash memories

Mission-critical applications usually presents several critical issues: the required level of dependability of the whole mission always implies to address different and contrasting dimensions and to evaluate the tradeoffs among them. A mass-memory device is always needed in all mission-critical applications: NAND flash-memories could be used for this goal. Error Detection And Correction (EDAC) techniques are needed to improve dependability of flash-memory devices. However also testing strategies need to be explored in order to provide highly dependable systems. Integrating these two main aspects results in providing a fault-tolerant mass-memory device, but no systematic approach has so far been proposed to consider them as a whole. As a consequence a novel strategy integrating a particular code-based design environment with newly selected testing strategies is presented in this pape

Palliation of complex cardiac anomalies with subaortic obstruction: New operative approach

AbstractThe modified Fontan operation for complex cardiac anomalies associated with subaortic obstruction entails a high surgical risk. It is likely that ventricular hypertrophy secondary to chronic pressure overload plays a significant role. This problem was approached with a new type of palliative operation comprising both a proximal pulmonary artery to ascending aorta anastomosis and a bidirectional cavopulmonary anastomosis.This operation was performed in six children ranging in age from 26 to 63 months. There was one intraoperative death due to hemorrhage. In one patient, a pulmonary to aorta conduit caused compression of the right coronary artery; the problem was solved by lengthening the conduit with a second period of cardiopulmonary bypass.The five survivors experienced an uneventful postoperative course. Repeat cardiac catheterization in these five patients showed low pressure in the cavopulmonary system (mean 10 mm Hg), absence of a gradient at rest between the systemic ventricle and aorta and fair arterial oxygenation (mean 82%). A technetium-99m perfusion lung scan visualized a slight prevalence of pulmonary blood flow ipsilateral to the shunt in three cases, whereas in one case preferential flow to the right lung was associated with a narrowing at the site of the cavopulmonary anastomosis. Mild hypoperfusion of the anterior pulmonary segments was observed in two cases.Both pressure and volume overload are abolished with this procedure and a satisfactory oxygenation is provided. Low venous pressure in the coronary, hepatic and renal areas as well as the short bypass time may explain the smoothness of the postoperative course in our patients. It is conceivable that oxygenation can be improved by a modified Fontan operation at a lower operative risk than is obtained with a single stage procedure because of regression of ventricular hypertrophy. Long-term follow-up indicates the value of this operation as a form of definitive palliation

First examples of pyran based colorants as sensitizing agents of p-Type Dye-Sensitized solar cells

Three different pyran based dyes were synthesized and tested for the first time as photosensitizers of NiO based p-type dye-sensitized solar cells (p-DSSC). The molecules feature a similar molecular structure and are based on a pyran core that is functionalized with electron acceptor groups of different strength and is symmetrically coupled to phenothiazine donor branches. Optical properties of the dyes are deeply influenced by the nature of the electron-acceptor group, so that the overall absorption of the three dyes covers the most of the visible spectrum. The properties of devices based on the NiO electrodes sensitized with the investigated dyes were evaluated under simulated solar radiation: the larger short circuit current density exceeded 1mA/cm2 and power conversion efficiency as high as 0.04% could be recorded. The performances of the fabricated p-DSSC have been compared to a reference cell sensitized with P1, a high level benchmark, which afforded a photoelectrochemical activity similar to the best example of our pyran sensitized devices (1.19 mA/cm2 and 0.049%)

Comparison of two different debonding techniques in orthodontic treatment

The purpose of this research is to investigate whether and how the adhesive bond failure site varied in relation to the material used for the orthodontic bonding and debonding technique applied

Docimologic approach for the evaluation of teachers’ digital and didactic competences

El presente trabajo constituye una reflexión sobre la evaluación de la educación en los entornos virtuales universitarios. Pretende dar cuenta de las características generales los principales elementos implicados en la presente cuestión y las relaciones entre ellos. A tal fin, se parte de una perspectiva docimológica para establecer vínculos con la evaluación de las competencias didácticas y digitales requeridas en profesores universitarios que desempeñan sus actividades en los entornos instructivos virtuales, ya sea en su totalidad o parcialmente. Se plantean algunos avances en los estudios sobre las definiciones de las competencias involucradas y se exponen diversas consideraciones y cuestionamientos sobre su evaluación. Aparecen así los estándares de desempeño como factores claves para el diseño curricular y los criterios de evaluación. No obstante, parece ser necesario establecer indicadores en niveles básico y específico, para poder evaluar de una manera más integral la competencia digital. Este escrito aporta a la teoría sobre el conocimiento de la evaluación de las competencias digitales y didácticas del docente universitario y ofrece un sustento a la construcción de marcos para investigaciones presentes y potenciales futuras.Este trabalho é uma reflexão sobre a avaliação da educação em ambientes virtuais da Universidade. Pretende-se dar conta das características gerais os principais elementos envolvidos na questão presente e as relações entre eles. Para tal, é uma perspectiva docimológica estabelecer vínculos com a avaliação de competências digitais e ensino exigido por professores universitários que realizam suas atividades em ambientes virtuais com instrução, na totalidade ou parcialmente. Surgem alguns progressos nos estudos sobre as definições das competências envolvidas e define várias considerações e perguntas sobre a sua avaliação. Assim, aparecem os padrões de desempenho como fatores-chave para os critérios de concepção e avaliação de currículo. No entanto, parece necessário estabelecer indicadores em níveis Basic e específico, para avaliar a competência digital de forma mais abrangente. Este ensaio traz a teoria do conhecimento de competências digitais e didáticas da Universidade avaliação docente e fornece uma subsistência para a construção de quadros de actuais e potenciais futuras pesquisas.This work is a reflection about the assessment in virtual environments of higher education. Seeks to explain the general characteristics of the main elements involved in this issue and the relations between them. To this end, we consider a docimologic view to establish links with the assessment of digital and didactic competences required by scholars who are active in virtual instructional environments, either in whole or in part. We discuss some advances in studies on the definitions of the competences involved and we present some considerations and questions about their assessment. The performance standards show up as key factors in curriculum design and assessment criteria. However, it seems necessary to establish indicators in basic and specific levels, in order to assess the digital competence in a more comprehensive way. This paper contributes to theory on knowledge of digital and didactic competences assessment of the scholars in higher education and provides support to frameworks for present and potential future researches

GaN-based modulation doped FETs and UV detectors

Abstract GaN based modulation doped field effect transistors (MODFETs) and ultraviolet detectors are critically reviewed. AlGaN/GaN MODFETs with CW power levels of about 6 W (in devices with 1 mm gate periphery) and a minimum noise figure of 0.85 dB with an associated gain of 11 dB have been obtained at 10 GHz. As a precursor to solar-blind detectors that will be operative around 280 nm, where the solar radiation is absorbed by the ozone layer surrounding the earth, detector arrays with pixel sizes of 32×32 operative near the solar-blind region have been achieved. One does not have to rely on imagination to predict that devices with much improved performance will continue to be developed

The Building Information Model and the IFC standard: analysis of the characteristics necessary for the acoustic and energy simulation of buildings

The new European Directive 2014/24 / EU requires for all member States the use of BIM procedures in the construction of public buildings. The countries belonging to the European Union shall be obliged to transpose the Directive and adapt their procedures to that effect. The paper analyzes the IFC format, the only recognized by the European Directive Standards for BIM procedures, in order to assess its use for simulations of buildings. IFC, described by the ISO 16739 (2013), is today a standard that describes the topology of the constructive elements of the building and what belongs to it overall. The format includes geometrical information on the room and on all building components, including details of the type for performance (transmittance, fire resistance, sound insulation), in other words it is an independent object file for the software producers to which, according to the European Directive, it will be compulsory to refer in the near future, during the different stages of the life of a building from the design phase, to management and possible demolition at the end of life. The IFC initiative began in 1994, when an industry consortium invested in the development of a set of C ++ classes that can support the development of integrated applications. Twelve US companies joined the consortium: these companies that were included initially are called the consortium "Industry Alliance for Interoperability". In September 1995 the Alliance opened up membership to all interested parties, and in 1997 changed its name to "International Alliance for Interoperability". The new alliance was reconstituted as a non-profit organization, with the aim of developing and promoting the '' Industry Foundation Class "(IFC) as a neutral data model for the building product that were useful to gather information throughout the life cycle of a building facility. Since 2005 the Alliance has been carrying out its activities through its national chapters called SMART building. The present study aims at evaluating the IFC, comparing the information and data contained in it, with other formats already used for energy simulations of buildings such as the gbXML (Green Building XML), highlighting the missing required information and proposing the inclusion of new ones to issue the energy and acoustic simulation. More generally the attention is focused to building physics simulation software devoted to exploit the BIM model potential enabling interoperability

Nefrocoloptosis : Tratamiento por la técnica de Alberto Guntierrez

Desde que Dowel de Nueva Orleans en 1877 realizó la primer fijación de riñón con resultado poco feliz, numerosas técnicas se han propuesto para corregir la nefroptosis. Relacionadas con la vía de abordaje, pueden reunirse en dos grandes grupos: las que siguen la vía lumbar y las que se realizan por vía abdominal. En el transcurso del tiempo también los cirujanos al mostrar su preferencia por determinado procedimiento, formaron dos frentes en relación con la disciplina quirúrgica cultivada: los urólogos inclinados hacia la vía lumbar y los cirujanos generales hacia la via abdominal. El procedimiento de Alberto Gutierrez marcó una nueva época en el tratamiento de la ptosis renal. Su estudio sobre la embriología, la anatomía y la fisiopatología de la celda renal y su contenido, lo llevaron a la realización de la técnica que hoy conocemos con su nombre y a la que el tiempo ha consagrado.Tesis digitalizada en SEDICI gracias a la colaboración de la Biblioteca de la Facultad de Ciencias Médicas (UNLP).Facultad de Ciencias Médica

A Community-Structure-Based Method for Estimating the Fractal Dimension, and its Application to Water Networks for the Assessment of Vulnerability to Disasters

AbstractMost real-world networks, from the World-Wide-Web to biological systems, are known to have common structural properties. A remarkable point is fractality, which suggests the self-similarity across scales of the network structure of these complex systems. Managing the computational complexity for detecting the self-similarity of big-sized systems represents a crucial problem. In this paper, a novel algorithm for revealing the fractality, that exploits the community structure principle, is proposed and then applied to several water distribution systems (WDSs) of different size, unveiling a self-similar feature of their layouts. A scaling-law relationship, linking the number of clusters necessary for covering the network and their average size is defined, the exponent of which represents the fractal dimension. The self-similarity is then investigated as a proxy of recurrent and specific response to multiple random pipe failures – like during natural disasters – pointing out a specific global vulnerability for each WDS. A novel vulnerability index, called Cut-Vulnerability is introduced as the ratio between the fractal dimension and the average node degree, and its relationships with the number of randomly removed pipes necessary to disconnect the network and with some topological metrics are investigated. The analysis shows the effectiveness of the novel index in describing the global vulnerability of WDSs