3,241 research outputs found

    Multi-sensor system using plastic optical fibers for intrinsically safe level measurements

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    A system for measuring liquid level in multiple tanks using optical fibe technology has been developed. Oil fiel service industry or any sector requiring liquid level measurements in flammabl atmospheres can be benefite from this intrinsically safe technology. The device used a single lens for the emitting and receiving fibe and it is based on amplitude variations as a function of the liquid distance and not in time of fligh or phase detection. Being the firs fiber-opti liquid level sensor with those characteristics for long ranges (>200 cm). A simple model to describe their behavior has been derived and tested on two prototypes. A Monte-Carlo method is used to fi the experimental data and obtain the model parameters. High accuracy between experimental data and fitte curve is obtained. The prototypes have a good linearity, better than 1.5% FS (full scale). Sensor heads are made of plastic optical fiber (POF) that are easy to handle, flexible and economical. They are excited by 650 nm lasers, housed in ST-connectors to obtain compact and rough prototypes. Optical multiplexing is used to increase the measuring safety area. Frequency division multiplexing is used to address each sensor head. A discussion about the influenc of tilts and aberrations is also included.Publicad

    Empowerment in the Public Sector: Testing the Influence of Goal Orientation

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    Empowerment has emerged as an important new issue in the public sector organization setting in the wake of mainstream new public management (NPM). Nevertheless, few studies in this frame have combined structural (managerial) and psychological (individual) approaches in an integrative study of empowerment. There is also a need to examine the moderating variables involved in this relationship, as well as to extend research on work motivation in public management. This study explores the effect of structural empowerment on psychological empowerment, and it also draws on goal orientation (GO) theory to examine the moderating role of employees’ GO in this link. The model is tested on a sample of 521 Spanish local authority employees. The results do not confirm the direct link between structural and psychological empowerment, but show that learning GO has considerable moderating power in this relationship, and its interaction with structural empowerment affects employees’ psychological empowerment levels

    Multi-Sensor System For Level Measurements With Optical Fibres

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    A system for measuring liquid level in multiple tanks using optical fibre technology has been developed. The oil field service industry can benefit from this intrinsically safe technology. Plastic optical fibre (POF) sensor heads are excited by a 650 nm laser. Laser diodes are housed in ST connectors to obtain compact and rough prototypes and these connectors are also used in the fibre pigtails. Optical multiplexing is used to increase the measuring safety area. POF splitters and connectors are used to combine all the receiving sensor head fibres in a single one. Frequency division multiplexing is used to address each sensor head. The global system is controlled through a user friendly software application running in a PC connected to the system via an RS-232 port. A scalable prototype with a range greater than 2 meter, good linearity, better than 1.5% FS (full scale), high accuracy and resolution is developed using a unique lens to collimate and focus the light. Measurements are taken to validate the designs. Up to 8 sensor heads can be connected in the present implementation. But a greater number of sensors can be allocated with minor modifications in the electronics.Universidad Carlos III de MadridPublicad

    Prediction of destructive properties using descriptive analysis of nd measurements

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    Three groups of measurements related to peach maturity were acquired through destructive (D) mechanical tests (Magness Taylor Firmness, MTF), mechanical non destructive (ND) tests, and ND optical spectroscopy (Optical indexes). The relationship between these groups of variables was studied in order to estimate D mechanical measurements (MTF, with higher instrumental and sampling variability, time consuming, generally used as a reference for the assessment of peach handling), from ND measurements (quick, applicable on line, dealing better with the high variability found in fruit products). Multivariate exploratory analysis was used to extract the structure of the data. The information about the data structure of ND measurements, the relationship of MTF with the space defined by ND variables, and the expert knowledge regarding to the dataset was then used for modelling MTF (R 2 =0.72 and standard error on validation 5.73 N

    Análisis del error sistemático en la sustracción

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    En este artículo presentamos resultados de investigación relacionados con la tipología, naturaleza y evolución de los errores en la sustracción. El objetivo principal de la investigación trata de indagar sobre si en nuestro contexto escolar se producen errores sistemáticos y si disminuyen a lo largo de la escolaridad. Asimismo, comparamos los resultados obtenidos con los aportados por autores de referencia en este campo de investigación. Para ello, efectuamos un análisis sobre 7.140 restas realizadas por niños/as escolarizados en 2º, 3º, 4º, 5º y 6º de Educación Primaria. Los resultados demuestran la existencia de errores sistemáticos y tipología concreta de los mismos, hecho de indudable valor a la hora de programar didácticamente el proceso de enseñanza.In this article, we presented results related to the typology, nature and evolution of the errors in subtraction. The main aim, is to examine if in our school context systematic errors take place and if these decrease throughout schooling. Also, we compared our results with the ones contributed by authors of reference in this field of research. To do so, we carried out an analysis on 7140 subtractions made by children in our educational system. The results demonstrate the existence of systematic errors in our scholastic context, a fact of doubtless value when programming the learning process didactically

    Potential Use of Wild Einkorn Wheat for Wheat Grain Quality Improvement: Evaluation and Characterization of Glu-1, Wx and Ha Loci

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    Wild einkorn (Triticum monococcum L. ssp. aegilopoides (Link) Thell.) is a diploid wheat species from the Near East that has been classified as an ancestor of the first cultivated wheat (einkorn; T. monococcum L. ssp. monococcum). Its genome (Am), although it is not the donor of the A genome in polyploid wheat, shows high similarity to the Au genome. An important characteristic for wheat improvement is grain quality, which is associated with three components of the wheat grain: endosperm storage proteins (gluten properties), starch synthases (starch characteristics) and puroindolines (grain hardness). In the current study, these grain quality traits were studied in one collection of wild einkorn with the objective of evaluating its variability with respect to these three traits. The combined use of protein and DNA analyses allows detecting numerous variants for each one of the following genes: six for Ax, seven for Ay, eight for Wx, four for Gsp-1, two for Pina and three for Pinb. The high variability presence in this species suggests its potential as a source of novel alleles that could be used in modern wheat breeding

    Allelic Variation of Puroindolines Genes in Iranian Common Wheat Landraces

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    Wheat is one of the most widely grown crops in the world. One of the traits that defines wheat quality is grain hardness, which is determined by puroindolines (PINA and PINB) proteins encoded with Pina-D1 and Pinb-D1 genes. In this study, the diversity of Pina-D1 and Pinb-D1 was evaluated in a collection of 271 Iranian common wheat (Triticum aestivum L. ssp. aestivum) landraces, whose kernels had previously been classified as hard or semi-hard based on PSI analysis. Three alleles previously described as associated with hard grain were detected in the collection: Pinb-D1b in 11 accessions, Pinb-d1ab in 175 accessions, and Pinb-d1p in 80 accessions. In addition, a novel allele tentatively named Pinb-d1ak was detected in Pinb-D1 and was characterized by a change at position 140 of the deduced protein (cysteine/tyrosine). On average, the accessions with this allele showed a lower PSI value than the accessions with other Pin allele. This means that this novel allele may be associated with harder grains than other Pin alleles and could be used by breeding programs targeting different grain hardness levels. This study highlights the importance of conserving and characterizing wheat genetic resources that could be used as sources of genetic variability in breeding programs

    Virtual restitution of the parietal decoration in the Sala del Mosaico de los Amores, Cástulo Archaelogical site (Linares, Spain)

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    The use of photogrammetry in the field of archaeology is increasingly widespread. In the case of restoration, the use of 3D contributes to facilitating the complex process of an intervention and bringing the artwork closer to the general public. This paper describes the application of 3D modelling techniques in the specific case of the Roman wall paintings from the Sala del Mosaico de los Amores, in Castulo Archaeological Site (Linares, province of Jaén). These paintings were found in 2011, collapsed over the mosaic pavement, and they were moved to the University of Granada for their restoration. After the intervention, the photogrammetric surveys of the different fragments and of the room to which they belong were developed, and the virtual restitution was generated, therefore making it possible for the general public to reliably appreciate how the room would look like with the parietal decoration located in-situ.Ministry of Economy and CompetitivenessEuropean Regional Development Fund (MINECO/FEDER, UE) HAR2015-66139-PResearch project "Chromatic treatments in architecture of Islamic tradition. Techniques and Conservation" by the Andalusian Regional Government, Department of Economy, Innovation, Science and Employment P12 HUM 1941German Research Foundation (DFG
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