962 resultados para Built-in test
Resumo:
The FY 2006 budget we present to you today was built from the ground up and is the result of a budget process that focuses on priorities and results. Faced with difficult choices, we are heartened by the progress we have achieved with your cooperation and collaboration. Fulfilling our responsibility to Iowa children, together we have focused resources on cing class sizes and reversed an eight-year decline in test scores. As a result, Iowa students have reachieved four straight years of improved test scores, ranking among America’s best.
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BACKGROUND: The construct of "meaning in life" (MiL) has raised the interest of clinicians working in psycho-oncology and end-of-life care. It has become a topic of scientific investigation where diverse assessment approaches have been applied. Aims: We present a comprehensive systematic review of existing MiL assessment instruments. METHODS: Electronic searches of articles published in English peer-reviewed journals were performed in Psycinfo, Medline, Embase and Cinahl. Instruments are appraised with regard to ten measurement properties. RESULTS: In total, 59 nomothetic and idiographic MiL instruments were identified. Most instruments were developed in North America and meet basic psychometric criteria. They assess presence of and search for MiL, crisis and sources of MiL, meaning making, meaningful activity, MiL in the context of illness, breadth, depth, and other structural indicators. These aspects are largely consistent with existing MiL definitions. Nine out of 59 instruments included cancer populations in test development. CONCLUSIONS: This overview of available instruments underscores the complexity of the construct and might assist researchers to select an appropriate instrument for their research needs. Finally, it points to the need for more integrative theorizing and research on MiL. Copyright © 2012 John Wiley & Sons, Ltd.
Resumo:
The FY 2008 budget we present to you today was built from the ground up and is the result of a budget process that focuses on priorities and results. Faced with difficult choices, we are heartened by the progress we have achieved with your cooperation and collaboration. Fulfilling our responsibility to Iowa children, together we have focused resources on cing class sizes and reversed an eight-year decline in test scores. As a result, Iowa students have reachieved four straight years of improved test scores, ranking among America’s best.
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This study aims to provide a passive sampling approach which can be routinely used to investigate polychlorinated biphenyl (PCB) sources in rivers. The approach consists of deploying low density polyethylene (LDPE) strips downstream and upstream of potential PCB sources as well as in their water discharges. Concentrations of indicator PCBs (iPCBs) absorbed in samplers (Cs) from upstream and downstream sites are compared with each other to reveal increases of PCB levels. Cs measured in water discharges are used to determine if released amounts of PCBs are compatible with increases revealed in the river. As water velocity can greatly vary along a river stretch and influences the uptake at each site in a different way, differences in velocity have to be taken into account to correctly interpret Cs. LDPE strips were exposed to velocities between 1.6 and 37 cm s−1 using a channel system built in the field. Relationships between velocity and Cs were established for each iPCB to determine the expected change in Cs due to velocity variations. For PCBs 28 and 52, this change does not exceed a factor 2 for velocity variations in the range from 1.6 to 100 cm s−1 (extrapolated data above 37 cm s−1). For PCBs 101, 138, 153 and 180, this change only exceeds a factor 2 in the case of large velocity variations. The approach was applied in the Swiss river Venoge to first conduct a primary investigation of potential PCB sources and then conduct thorough investigations of two suspected sources.
Resumo:
This PhD thesis addresses the issue of scalable media streaming in large-scale networking environments. Multimedia streaming is one of the largest sink of network resources and this trend is still growing as testified by the success of services like Skype, Netflix, Spotify and Popcorn Time (BitTorrent-based). In traditional client-server solutions, when the number of consumers increases, the server becomes the bottleneck. To overcome this problem, the Content-Delivery Network (CDN) model was invented. In CDN model, the server copies the media content to some CDN servers, which are located in different strategic locations on the network. However, they require heavy infrastructure investment around the world, which is too expensive. Peer-to-peer (P2P) solutions are another way to achieve the same result. These solutions are naturally scalable, since each peer can act as both a receiver and a forwarder. Most of the proposed streaming solutions in P2P networks focus on routing scenarios to achieve scalability. However, these solutions cannot work properly in video-on-demand (VoD) streaming, when resources of the media server are not sufficient. Replication is a solution that can be used in these situations. This thesis specifically provides a family of replication-based media streaming protocols, which are scalable, efficient and reliable in P2P networks. First, it provides SCALESTREAM, a replication-based streaming protocol that adaptively replicates media content in different peers to increase the number of consumers that can be served in parallel. The adaptiveness aspect of this solution relies on the fact that it takes into account different constraints like bandwidth capacity of peers to decide when to add or remove replicas. SCALESTREAM routes media blocks to consumers over a tree topology, assuming a reliable network composed of homogenous peers in terms of bandwidth. Second, this thesis proposes RESTREAM, an extended version of SCALESTREAM that addresses the issues raised by unreliable networks composed of heterogeneous peers. Third, this thesis proposes EAGLEMACAW, a multiple-tree replication streaming protocol in which two distinct trees, named EAGLETREE and MACAWTREE, are built in a decentralized manner on top of an underlying mesh network. These two trees collaborate to serve consumers in an efficient and reliable manner. The EAGLETREE is in charge of improving efficiency, while the MACAWTREE guarantees reliability. Finally, this thesis provides TURBOSTREAM, a hybrid replication-based streaming protocol in which a tree overlay is built on top of a mesh overlay network. Both these overlays cover all peers of the system and collaborate to improve efficiency and low-latency in streaming media to consumers. This protocol is implemented and tested in a real networking environment using PlanetLab Europe testbed composed of peers distributed in different places in Europe.
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Water erosion is the major cause of soil and water losses and the main factor of degradation of agricultural areas. The objective of this work was to quantify pluvial water erosion from an untilled soil with crop rows along the contour, in 2009 and 2010, on a Humic Dystrupept, with the following treatments: a) maize monoculture; b) soybean monoculture; c) common bean monoculture; d) intercropped maize and bean, exposed to four simulated rainfall tests of on hour at controlled intensity (64 mm h-1). The first test was applied 18 days after sowing and the others; 39, 75 and 120 days after the first test. The crop type influenced soil loss through water erosion in the simulated rainfall tests 3 and 4; soybean was most effective in erosion control in test 3, however, in test 4, maize was more effective. Water loss was influenced by the crop type in test 3 only, where maize and soybean were equally effective, with less runoff than from the other crops. The soil loss rate varied during the runoff sampling period in different ways, demonstrating a positive linear relationship between soil and water loss, in the different rainfall tests.
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In recent years, ultra-thin whitetopping (UTW) has evolved as a viable rehabilitation technique for deteriorated asphalt cement concrete (ACC) pavement. Numerous UTW projects have been constructed and tested, enabling researchers to identify key elements contributing to their successful performance. These elements include foundation support, the interface bonding condition, portland cement concrete (PCC) overlay thickness, synthetic fiber reinforcement usage, joint spacing, and joint sealing. The interface bonding condition is the most important of these elements. It enables the pavement to act as a composite structure, thus reducing tensile stresses and allowing an ultra-thin PCC overlay to perform as intended. Although the main factors affecting UTW performance have been identified in previous research, neither the impact that external variables have on the elements nor the element interaction have been thoroughly investigated. The objective of this research was to investigate the interface bonding condition between an ultra-thin PCC overlay and an ACC base over time, considering the previously mentioned variables. Laboratory testing and full scale field testing were planned to accomplish the research objective. Laboratory testing involved monitoring interface strains in fabricated PCC/ACC composite test beams subjected to either static or dynamic flexural loading. Variables investigated included ACC surface preparation, PCC thickness, and synthetic fiber reinforcement usage. Field testing involved monitoring PCC/ACC interface stains and temperatures, falling weight deflectometer (FWD) deflection responses, direct shear strengths, and distresses on a 7.2 mile Iowa Department of Transportation (Iowa DOT) UTW project (HR-559). The project was located on Iowa Highway 21 between Iowa Highway 212 and U.S. Highway 6 in Iowa County, near Belle Plaine, Iowa. Variables investigated included ACC surface preparation, PCC thickness, synthetic fiber reinforcement usage, joint spacing, and joint sealing. This report documents the planning, equipment selection, and construction of the project built in 1994.
Resumo:
Methods for the extraction of features from physiological datasets are growing needs as clinical investigations of Alzheimer’s disease (AD) in large and heterogeneous population increase. General tools allowing diagnostic regardless of recording sites, such as different hospitals, are essential and if combined to inexpensive non-invasive methods could critically improve mass screening of subjects with AD. In this study, we applied three state of the art multiway array decomposition (MAD) methods to extract features from electroencephalograms (EEGs) of AD patients obtained from multiple sites. In comparison to MAD, spectral-spatial average filter (SSFs) of control and AD subjects were used as well as a common blind source separation method, algorithm for multiple unknown signal extraction (AMUSE). We trained a feed-forward multilayer perceptron (MLP) to validate and optimize AD classification from two independent databases. Using a third EEG dataset, we demonstrated that features extracted from MAD outperformed features obtained from SSFs AMUSE in terms of root mean squared error (RMSE) and reaching up to 100% of accuracy in test condition. We propose that MAD maybe a useful tool to extract features for AD diagnosis offering great generalization across multi-site databases and opening doors to the discovery of new characterization of the disease.
Use of Reagent Grade Versus Industrial Grade Trichlorethylene in Asphalt Recoveries, MLR-83-05, 1983
Resumo:
This is a continuation of a project initiated a year ago to determine any differences in test results on recovered asphalt cements caused by the use of industrial grade of solvent as compared with the reagent grade. AASHTO specifies the use of reagent grade of trichlorethylene, but the Laboratory uses industrial grade which costs much less. Last year this objective of the project was aborted when it was found that a larger difference in test results was obtained between the two distillation apparatuses than between the two solvents, Then all efforts were directed toward obtaining uniformity in test results between the apparatuses under the east hood as compared with that under the west hood. Considerable progress was made toward this end. (See report under this same title dated April 1982). The objective this year was to again evaluate the results when using both variables (apparatuses and solvents). Another objective developed later in this investigation; this was to determine any differences in test results on recovered asphalt cements caused by the use of reclaimed trichlorethylene (from the distillation process) as compared with the use of industrial grade of solvent. At the present time the reclaimed trichlorethylene is discarded. If the reclaimed solvent could be used for further recoveries, a considerable savings in solvent costs would result.
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The objective of this work was to build mock-ups of complete yerba mate plants in several stages of development, using the InterpolMate software, and to compute photosynthesis on the interpolated structure. The mock-ups of yerba-mate were first built in the VPlants software for three growth stages. Male and female plants grown in two contrasting environments (monoculture and forest understory) were considered. To model the dynamic 3D architecture of yerba-mate plants during the biennial growth interval between two subsequent prunings, data sets of branch development collected in 38 dates were used. The estimated values obtained from the mock-ups, including leaf photosynthesis and sexual dimorphism, are very close to those observed in the field. However, this similarity was limited to reconstructions that included growth units from original data sets. The modeling of growth dynamics enables the estimation of photosynthesis for the entire yerba mate plant, which is not easily measurable in the field. The InterpolMate software is efficient for building yerba mate mock-ups.
Resumo:
The imperial cult area of Tarraco was built in the 1st century AD in the highest part of the city and presided over the seat of the Concilium Prouinciae Hispaniae Citerioris. It was a temenos with a similar layout to that of the Forum Pacis and architectural decoration imitating that of the Forum Augustum in Rome, where the use of marble was a fundamental part of the architectural and sculptural decorative programme. An extensive assemblage of marble was recovered during the excavations carried out under the Tarragona Cathedral Master Plan. It reflects the use of imperial quarries in the decorative programme and has been analyzed at the Unitat d’Estudis Arqueomètrics (ICAC) facilities. This assemblage reflects the wide panorama of marmora imported and used in the decoration of the temenos. Local varieties of marmora have been identified in Tarraco, plus a series of foreign marmora from quarries all over the Roman Empire (Greece, Turkey, Egypt and North Africa). All this shows the involvement of the imperial power in the monumental architecture of the capital of the prouincia Hispania Citerior.
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Painelajittimien kyky poistaa epäpuhtauksia on parantunut erityisesti roottorien ja sihtirumpujen kehityksen myötä. Painelajittimella pystytään nykyisin poistamaan yhä pienempiä roskapartikkeleja, minkä ansiosta painelajittimilla pystytään korvaamaan pyörrepuhdistimia hienolajittelussa. Nykyään ratkaisevaa on lajittimen mahdollinen toimintasakeus ja energiankulutus, joihin voidaan vaikuttaa roottori- ja sihtiratkaisuin sekä laitteen ajotavalla. Lajittimen toimintasakeutta nostamalla voitaisiin saavuttaa etuja tuotantoprosessissa pienempien virtauksien ja prosessin paremman ajettavuuden vuoksi. Työssä tarkasteltiin painelajittimen rakenneparametreista roottorin ja sihtirummun sekä ajoparametreista syöttösakeuden, massarejektisuhteen, tuotantomäärän ja roottorin kehänopeuden vaikutusta painelajittimen toimintaan. Erityisesti tutkittiin mahdollisuuksia nostaa lajittelusakeutta ja sakeuden nostonvaikutusta lajittimen energiankulutukseen. Sellutehtaaseen rakennetussa koelajitinlinjassa pystyttiin perusrakenteeltaan nykyisenlaisella painelajittimella muuttamalla roottorin ja sihdin rakennetta sekä nostamalla roottorin kehänopeutta lajittelemaan laitteen mitoitustuotannossa massaa korkeimmillaan 4,8 %:n sakeudessa. Suurin saavutettu sakeus, jossa energiankulutusta voidaanpitää hyväksyttävänä oli 4,4%. Nykyisellä ajotavalla ja roottori- ja sihtirakenteella pystyttiin lajittelemaan massaa 3,2 %:ssa. Tuloksista voidaan päätellä, että massan lajittelu yli 5 %:n sakeudessa on mahdollista roottorirakennetta edelleen kehittämällä.
Resumo:
Työ tutkii yritysportaalin roolia organisaation tietojohtamisessa. Tutkimusongelman ratkaisemiseksi luodaan viitekehys, jossa yritysportaalin ja tietojohtamisen teoriat linkittyvät. Työn empiirisessä osassa viitekehys on pohjana case-yritykselle rakennettavalle yritysportaalille. Laadullinen tutkimus käsittää teoriaosuuden sekä osallistuvaan case-tutkimukseen perustuvan empiriaosuuden. Työn runko muodostuu kahden vastakkaisen tietojohtamisajattelun vuoropuhelusta, jotka ovat informaatioteknologiaan- ja strategiseen johtamiseen perustuvat näkökulmat. Toimivan tietojohtamismallin täytyy sisältää molemmat aspektit. Jokainen organisaatio tarvitsee informaation hallintaan liittyviä toiminnallisuuksia ja täten eksplisiittisen tiedon hallinta tietojärjestelmien avulla on onnistuneen tietojohtamisen kulmakiviä. Tätä perusinfrastruktuuria on mahdollista laajentaa hiljaisen tiedon hallintaan perustuvilla tietojohtamismenetelmillä. Työn ratkaisu näiden kahden näkemyksen, 'kovan' informaatioteknogiaan painottuvan sekä 'pehmeän' ihmisnäkökulman integrointiin, on yritysportaali. Työssä käytettävä yritysportaalin viitekehys rakentuu kolmeen päätoiminnallisuuteen; sisällönhallintaan, yhteistyöominaisuuksiin ja liiketoimintatiedon hallintaan. Työ todistaa yhteyden viitekehyksen sekä tietojohtamisen perusmallien, kuten tietojohtamisen prosessimallin sekä tietoympäristöjen välillä. Yritysportaali voi täten toimia, ei ainoastaan yksittäisten tietojohtamistyökalujen implementoinnissa, vaan tietojohtamisstrategian luomisen apuna tarjoten alustan tai 'katalyytin' kokonaisvaltaiselle tietojohtamiselle.
Resumo:
The present study was done with two different servo-systems. In the first system, a servo-hydraulic system was identified and then controlled by a fuzzy gainscheduling controller. The second servo-system, an electro-magnetic linear motor in suppressing the mechanical vibration and position tracking of a reference model are studied by using a neural network and an adaptive backstepping controller respectively. Followings are some descriptions of research methods. Electro Hydraulic Servo Systems (EHSS) are commonly used in industry. These kinds of systems are nonlinearin nature and their dynamic equations have several unknown parameters.System identification is a prerequisite to analysis of a dynamic system. One of the most promising novel evolutionary algorithms is the Differential Evolution (DE) for solving global optimization problems. In the study, the DE algorithm is proposed for handling nonlinear constraint functionswith boundary limits of variables to find the best parameters of a servo-hydraulic system with flexible load. The DE guarantees fast speed convergence and accurate solutions regardless the initial conditions of parameters. The control of hydraulic servo-systems has been the focus ofintense research over the past decades. These kinds of systems are nonlinear in nature and generally difficult to control. Since changing system parameters using the same gains will cause overshoot or even loss of system stability. The highly non-linear behaviour of these devices makes them ideal subjects for applying different types of sophisticated controllers. The study is concerned with a second order model reference to positioning control of a flexible load servo-hydraulic system using fuzzy gainscheduling. In the present research, to compensate the lack of dampingin a hydraulic system, an acceleration feedback was used. To compare the results, a pcontroller with feed-forward acceleration and different gains in extension and retraction is used. The design procedure for the controller and experimental results are discussed. The results suggest that using the fuzzy gain-scheduling controller decrease the error of position reference tracking. The second part of research was done on a PermanentMagnet Linear Synchronous Motor (PMLSM). In this study, a recurrent neural network compensator for suppressing mechanical vibration in PMLSM with a flexible load is studied. The linear motor is controlled by a conventional PI velocity controller, and the vibration of the flexible mechanism is suppressed by using a hybrid recurrent neural network. The differential evolution strategy and Kalman filter method are used to avoid the local minimum problem, and estimate the states of system respectively. The proposed control method is firstly designed by using non-linear simulation model built in Matlab Simulink and then implemented in practical test rig. The proposed method works satisfactorily and suppresses the vibration successfully. In the last part of research, a nonlinear load control method is developed and implemented for a PMLSM with a flexible load. The purpose of the controller is to track a flexible load to the desired position reference as fast as possible and without awkward oscillation. The control method is based on an adaptive backstepping algorithm whose stability is ensured by the Lyapunov stability theorem. The states of the system needed in the controller are estimated by using the Kalman filter. The proposed controller is implemented and tested in a linear motor test drive and responses are presented.
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The need for high performance, high precision, and energy saving in rotating machinery demands an alternative solution to traditional bearings. Because of the contactless operation principle, the rotating machines employing active magnetic bearings (AMBs) provide many advantages over the traditional ones. The advantages such as contamination-free operation, low maintenance costs, high rotational speeds, low parasitic losses, programmable stiffness and damping, and vibration insulation come at expense of high cost, and complex technical solution. All these properties make the use of AMBs appropriate primarily for specific and highly demanding applications. High performance and high precision control requires model-based control methods and accurate models of the flexible rotor. In turn, complex models lead to high-order controllers and feature considerable computational burden. Fortunately, in the last few years the advancements in signal processing devices provide new perspective on the real-time control of AMBs. The design and the real-time digital implementation of the high-order LQ controllers, which focus on fast execution times, are the subjects of this work. In particular, the control design and implementation in the field programmable gate array (FPGA) circuits are investigated. The optimal design is guided by the physical constraints of the system for selecting the optimal weighting matrices. The plant model is complemented by augmenting appropriate disturbance models. The compensation of the force-field nonlinearities is proposed for decreasing the uncertainty of the actuator. A disturbance-observer-based unbalance compensation for canceling the magnetic force vibrations or vibrations in the measured positions is presented. The theoretical studies are verified by the practical experiments utilizing a custom-built laboratory test rig. The test rig uses a prototyping control platform developed in the scope of this work. To sum up, the work makes a step in the direction of an embedded single-chip FPGA-based controller of AMBs.