975 resultados para PERFORMANCES
Resumo:
In this work we study the classification of forest types using mathematics based image analysis on satellite data. We are interested in improving classification of forest segments when a combination of information from two or more different satellites is used. The experimental part is based on real satellite data originating from Canada. This thesis gives summary of the mathematics basics of the image analysis and supervised learning , methods that are used in the classification algorithm. Three data sets and four feature sets were investigated in this thesis. The considered feature sets were 1) histograms (quantiles) 2) variance 3) skewness and 4) kurtosis. Good overall performances were achieved when a combination of ASTERBAND and RADARSAT2 data sets was used.
Resumo:
Ultrasuodatus on tehokas entsyymiliuosten konsentrointi- ja puhdistusmenetelmä. Prosessin ongelmana on kuitenkin kalvojen likaantumisesta johtuva suodatuksen aikainen vuon pienentyminen ja kalvojen hankala puhdistaminen. Oikeilla kalvovalinnoilla ja optimaalisilla pesustrategioilla voidaan suodatus- ja pesuaikoja lyhentää ja nain parantaa suodatusprosessin tehokkuutta ja tuotteen laatua. Työn kirjallisessa osassa on käsitelty entsyymiliuosten ja polymeerikalvojen suodatusprosessiin vaikuttavia ominaisuuksia. Työssä on esitelty myös pesuaineiden ja pesukemikaalien ominaisuuksia sekä pesuprosessiin vaikuttavia tekijöitä. Työn kokeellinen osa koostui kahdesta osasta. Työn ensimmäisessä osassa etsittiin entsyymiliuosten ultrasuodatusprosessiin sopivaa kalvoa vertailemalla kalvojen permeabiliteetteja, hydrofiilisyytta, varausta ja peseytyvyyttä. Suodatuksissa käytettiin kahta Roal Oy:n tuottamaa entsyymiliuosta ja suodatukset tehtiin DSS Labstak M20-laitteistolla. Työn toisen osan tarkoituksena oli etsiä entsyymiliuosten suodatuksessa käytettävien kalvojen likaantumisen syyt sekä tehokas puhdistusaine kalvojen pesuun. Tehokasta pesuainetta etsittiin liotuskokeilla ja laboratoriomittakaavan poikkivirtauslaitteistolla. Analysointeja tehtiin muun muassa FTIR- spektroskoopilla, vuomittauksilla, pyyhkäisyelektronimikroskoopilla ja kontaktikulmamittauksilla. Entsyymiliuosten suodatuksiin sopivan kalvon etsinnässä testattujen kalvojen välillä oli suuria eroja niin permeabiliteeteissa kuin likaantumisessa ja puhdistumisessa, mutta mikään kalvoista ei erottunut ylivoimaisesti parhaaksi. Pesuaineista kaupalliset membraanien puhdistukseen tarkoitetut emäksiset pesuaineet osoittautuivat tehokkaimmiksi lian poistajiksi.
Resumo:
Ningú no dubte ja del canvi de mentalitat que s’ha produït en els darrers anys en els compradors pel què fa al mercat de l’automòbil. La seguretat i el respecte per el medi ambient, són actualment dos dels factors claus que el consumidor té en compte a l’hora de comprar un vehicle. D’altra banda en els darrers anys la Unió Europea, ha fixat tota una sèrie normatives per tal de reduir les emissions nocives a l’atmosfera. Així doncs, més seguretat i menys emissions, signifiquen vehicles que incorporin components i sistemas cada cop més sofisticats, els quals, a la vegada, necessiten de bancs d’assaig i equips de test per tal de ser validats. Aquest fet ha provocat una revolució dins dels sistemes de test per a vehicles, per als quals han augmentat enormement les exigències en quan a precisions i repetibilitat per tal d’intentar reproduir, amb la màxima fiabilitat possible, les condicions de treball que hauran de suportar els components durant el seu ús real. Les característiques dels motors elèctrics, resulten ideals per a accionar aquest tipus d’aplicacions, ja que permeten un control del parell molt acurat i una repetibilitat quasi perfecte enfront d’altres sistemas utilitzats fins no fa massa temps. Aquesta demanda creixent d’aquest tipus de màquines elèctriques, obra una nova oportunitat de negoci per a les empreses fabricants de motors elèctrics. L’objectiu principal d’aquest treball és identificar i satisfer les necessitats dels clients, dins d’un mercat industrial concret: el mercat dels motors elèctrics per a bancs de proves de components per a la indústria de l’automoció. La fita és doncs la de proporcionar les eines necessàries per tal de que una empresa, fabricant de motors elèctrics de velocitat variable, pugui realitzar el disseny, desenvolupament i llançament comercial d’un nou tipus de motor, específicament pensat per aquest mercat, amb les màximes garanties d’èxit. Com a principal conclusió, el treball argumenta que el nou producte representa una oportunitat de negoci força atractiva i rendible per a l’empresa, i permetrà diversificar la oferta de la companyia cap a un nou sector fins ara no explotat.
Resumo:
The performances of eight kinds of insulators from electrical distribution lines in Salvador-BA, Brazil, were evaluated considering the chemical and physical local environmental pollution. The parameters that were chosen as characteristic for the insulators' properties were leakage current and partial electrical discharge. A data storage processing system and a communication link to the lab were built for data acquisition. The results show that the main contribution to the poor performance of the insulators is settleable magnetite particulate matter on the insulator in addition to the long term wetness time, t4.
Resumo:
The environmental impact of landfill is a growing concern in waste management practices. Thus, assessing the effectiveness of the solutions implemented to alter the issue is of importance. The objectives of the study were to provide an insight of landfill advantages, and to consolidate landfill gas importance among others alternative fuels. Finally, a case study examining the performances of energy production from a land disposal at Ylivieska was carried out to ascertain the viability of waste to energy project. Both qualitative and quantitative methods were applied. The study was conducted in two parts; the first was the review of literatures focused on landfill gas developments. Specific considerations were the conception of mechanism governing the variability of gas production and the investigation of mathematical models often used in landfill gas modeling. Furthermore, the analysis of two main distributed generation technologies used to generate energy from landfill was carried out. The review of literature revealed a high influence of waste segregation and high level of moisture content for waste stabilization process. It was found that the enhancement in accuracy for forecasting gas rate generation can be done with both mathematical modeling and field test measurements. The result of the case study mainly indicated the close dependence of the power output with the landfill gas quality and the fuel inlet pressure.
Resumo:
The primary objective of this thesis was to research delivery reliability of mill business unit of a forest industry company, especially timely and quantitative accuracy of sales orders. Delivery reliability is an important factor of customer satisfaction, which has a great influence for success of a company. The secondary objective was to find out reasons for possible problems of delivery reliability and give propositions for improvable performances. The empirical part of the thesis based on reporting database of the forest industry company’s ERP-software and detailed information of the mill system. The delivery reliability results of the mill business unit were compared to delivery reliability of similar mill business unit inside the forest industry company. The research results expressed problems in the supply chain. The delivery reliability reporting should be also developed further. This would advance delivery reliability monitoring. The improvement propositions of the thesis were logistic operation mode estimation, particular benchmarking of the compared mill business unit and more detailed survey on production delivery reliability.
Resumo:
A diagnostic instrument was developed to evaluate the basic chemistry concepts held by freshmen students of the three Chemistry undergraduate courses offered by the University of São Paulo. The instrument minimizes the use of algorithms or memorization by students and values high-order cognitive skills. Analysis of the students' performances reveals systematic use of "displacement reaction" as an algorithm and a mechanical use of Le Chatelier's Principle. Failure in comprehending the chemical equation and chemical language drives students to alternative models for chemical reactions in aqueous solution. For instance, reaction would occur between "ionic pairs" and/or between species situated in separate compartments.
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“L’altre Segon Quintet. Anàlisi formal i rítmic de l’evolució de la interpretació del repertori en els concerts en directe del Segon Quintet de Miles Davis” és un estudi històric i analític de la música de Miles Davis i el seu famós “Segon Quintet”. A diferència de la majoria de publicacions sobre aquesta banda, es centra únicament en els concerts en directe i el repertori que hi tocaven. Per treure a la llum la “màgia” que hi havia, he fet unes transcripcions amb un mètode propi de diverses versions de les mateixes peces al llarg dels anys i he anotat tots els fets rellevants en aspectes d’arranjaments, plantejaments estètics i interacció entre solistes i secció rítmica. Finalment he comprovat que aquesta “màgia” és fruit d’unes fórmules pautades i no és tan espontània com sembla en una primera escolta. Per altra banda, tots els músics de la banda contribueixen al so del grup, demostrant així la seva condició d’indispensables per la banda.
Resumo:
The results obtained in several yield tests, at an international level (mainly the famous PISA 2003 report, by the OCDE), have raised a multiplicity of performances in order to improve the students' yield regarding problem solving. In this article we set a clear guideline on how problems should be used in Mathematics lessons, not for obtaining better scores in the yield tests but for improving the development of Mathematical thinking in students. From this perspective, the author analyses, through eight reflections, how the concept of problem, transmitted both in the school and from society, influences the students
Resumo:
This project addresses methodological and technological challenges in the development of multi-modal data acquisition and analysis methods for the representation of instrumental playing technique in music performance through auditory-motor patterning models. The case study is violin playing: a multi-modal database of violin performances has been constructed by recording different musicians while playing short exercises on different violins. The exercise set and recording protocol have been designed to sample the space defined by dynamics (from piano to forte) and tone (from sul tasto to sul ponticello), for each bow stroke type being played on each of the four strings (three different pitches per string) at two different tempi. The data, containing audio, video, and motion capture streams, has been processed and segmented to facilitate upcoming analyses. From the acquired motion data, the positions of the instrument string ends and the bow hair ribbon ends are tracked and processed to obtain a number of bowing descriptors suited for a detailed description and analysis of the bow motion patterns taking place during performance. Likewise, a number of sound perceptual attributes are computed from the audio streams. Besides the methodology and the implementation of a number of data acquisition tools, this project introduces preliminary results from analyzing bowing technique on a multi-modal violin performance database that is unique in its class. A further contribution of this project is the data itself, which will be made available to the scientific community through the repovizz platform.
Resumo:
Analytical laboratories are expected to produce reliable results. Decision makers are guided in their actions (financial, legal and environmental) using analytical data provided by numerous laboratories. This work aimed to evaluate the analytical performance of Brazilian laboratories on producing trustworthy results. Nineteen laboratories, accredited and non-accredited ones, were contracted to analyze a USGS (United States Geological Survey) certified water sample for 17 chemical elements (mostly metals) without knowing the origin of the sample. Considering all the results produced, only 35% of them were valid. Three laboratories present satisfactory performances, whereas the majority showed a very poor overall performance. The outcomes of this work show the need for a more effective analytical quality program to Brazilian laboratories.
Resumo:
Water-in-crude oil emulsions are formed during petroleum production and asphaltenes play an important role in their stabilization. Demulsifiers are added to destabilize such emulsions,however the demulsification mechanism is not completely known. In this paper, the performances of commercial poly(ethylene oxide-b-propylene oxide) demulsifiers were studied using synthetic water-in-oil emulsions and model-systems (asphaltenes in organic solvent). No change in the asphaltene aggregate size induced by the demulsifier was observed. The demulsification performance decreased as the asphaltene aggregate size increased, so it can be suggested that the demulsification mechanism is correlated to the voids between the aggregates adsorbed on the water droplets surface.
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Silica obtained from rice husk after acid leaching and calcination was compared to commercial silica as a catalyst support. CaO and SnO2 catalysts were prepared by impregnation and tested in the transesterification of soybean oil and the esterification of oleic acid. CaO catalysts showed basic character and were the most active for transesterification, whereas SnO2 catalysts were acid and the most effective for esterification. In both cases the performances of the catalysts prepared with rice husk ash and commercial silica were similar. These results demonstrate that rice husk is a cost-effective and environmentally-friendly source of silica that can be used as a catalyst support.
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In this paper studies based on Multilayer Perception Artificial Neural Network and Least Square Support Vector Machine (LS-SVM) techniques are applied to determine of the concentration of Soil Organic Matter (SOM). Performances of the techniques are compared. SOM concentrations and spectral data from Mid-Infrared are used as input parameters for both techniques. Multivariate regressions were performed for a set of 1117 spectra of soil samples, with concentrations ranging from 2 to 400 g kg-1. The LS-SVM resulted in a Root Mean Square Error of Prediction of 3.26 g kg-1 that is comparable to the deviation of the Walkley-Black method (2.80 g kg-1).
Resumo:
This work describes three C8-stationary phases for high performance liquid chromatography based on silica metallized with ZrO2, TiO2 or Al2O3 layers, having poly(methyloctylsiloxane) immobilized onto their surfaces. The stationary phases were characterized using XRF, XAS, FTIR, SEM and elemental analysis to determine the physical characteristics of the oxide and polysiloxane layers formed on the surfaces and chromatographically to evaluate the separation parameters. The results show the changes on the silica surface and allowed proposing a structure for the oxide layer, being observed tetrahedral and octahedral structures, what is completely new in the literature. The formation of a homogeneous layer of metallic oxide (TiO2 and ZrO2) was observed on the silica. The C8-titanized and C8-aluminized stationary phases presented good chromatographic performances, with good values of asymmetry and efficiency. All stationary phase presented few loss of the polymeric layer after the HPLC, indicating that this layer is well attached on the metalized support.