991 resultados para Rosenthal Compact


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Vacuum pumps are very useful in physical, chemical and biological experiments. In this communication it is described the design of a compact and low cost water recirculating system employing a water-jet aspirator pump as the vacuum source. The system requires only a water pump, water-jet aspirator pump, commercial PVC water tubes and a drain connection.

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This study evaluates the application of an intelligent hybrid system for time-series forecasting of atmospheric pollutant concentration levels. The proposed method consists of an artificial neural network combined with a particle swarm optimization algorithm. The method not only searches relevant time lags for the correct characterization of the time series, but also determines the best neural network architecture. An experimental analysis is performed using four real time series and the results are shown in terms of six performance measures. The experimental results demonstrate that the proposed methodology achieves a fair prediction of the presented pollutant time series by using compact networks.

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The objectives of this work were to investigate the microstructure, crystallinity and thermal stability of nanofibrillated cellulose obtained from oat hulls using bleaching and acid hydrolysis at a mild temperature (45 ºC) followed by ultrasonication. The oat hulls were bleached with peracetic acid, and after bleaching, the compact structure around the cellulosic fibers was removed, and the bundles became individualized. The extraction time (30 or 60 min) did not affect the properties of the nanofibrillated cellulose, which presented a higher crystallinity index and thermal stability than the raw material (oat hulls). The nanocellulose formed interconnected webs of tiny fibers with diameters of 70-100 nm and lengths of several micrometers, producing nanofibers with a relatively high aspect ratio, thus indicating that these materials are suitable for polymer reinforcement.

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Tässä työssä arvioidaan kotitalouksien energiansäästöpotentiaalia valaistuksen osalta Suomessa. Euroopan Unioni on ratifioinut päästövähennystavoitteen 20 % koskien kaikkia primäärienergiantuotantomuotoja. Päästövähennystavoite on tarkoitus toteuttaa vuoteen 2020 mennessä. Tässä kandidaatintyössä arvioidaan saavutettavissa olevaa energiansäästöpotentiaalia Suomessa kotitalouksissa laitesähkön osalta. Energiansäästöpotentiaalin arviointi perustuu hehkulampun korvaamismahdollisuuksien vertailuun. Valaistuksessa voidaan saavuttaa jopa 75 % sähkönsäästö, kun korvataan yksi 60 W hehkulamppu vastaavan valomäärän tuottavalla energiansäästölampulla. Kokonaisuudessa kotitalouksien valaistuksessa on tehostamispotentiaalia noin 60 %. Valaistuksen tehostamisella saavutetaan noin 1,5 TWh säästö Suomen kokonaissähkökulutuksessa. Saavutettavat säästöt voivat olla jopa suuremmatkin, jos käytetään lisäksi älykästä valonohjausta. Johtopäätöksenä voidaan todeta, että tehostamispotentiaalia on merkittävästi ja tehostaminen on yksittäiselle kotitaloudelle taloudellisesti kannattavaa. Energiansäästöpotentiaalin toteuttamisen vaikutuksia kansantalouteen ei ole arvioitu.

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Diplomityössä on selvitetty Etelä-Karjalan maakunnan energian käyttöä nyt ja tulevaisuudessa. Tavoitteena on selvittää eri energialähteiden hankintavaihtoehtoja, sekä eri energialähteiden käytön kehittymissuunnat seuraavan 10 - 20 vuoden kuluessa. Diplomityö on tehty Etelä-Karjalan liiton toimeksiannosta ja sitä tullaan käyttämään taustaselvityksenä maakuntakaavan laadinnassa sekä maakunnan aluevarauksia määriteltäessä. Tarkoituksena on arvioida miten energiahuollon rakenne tulee muuttumaan tulevaisuudessa ja mikä merkitys tulevaisuuden energiaratkaisuilla on alueiden käyttöön ja aluerakenteeseen liittyen. Etelä-Karjala on osa Euroopan suurinta metsäteollisuuskeskittymää ja maakunta on Suomen suurimpia teollisuuden energian- ja sähkönkäyttäjiä. Etelä-Karjalan vahva metsäteollisuus ja sen käyttämät puupolttoaineet sekä sijainti Venäjän maakaasuvarojen läheisyydessä ja kattava maakaasuverkko vaikuttavat merkittävästi maakunnan energiataseeseen. Vuonna 2007 Etelä-Karjalan primäärienergiankäyttö oli 24,3 TWh, tästä uusiutuvien energialähteiden osuus oli 68 % ja fossiilisten energialähteiden osuus 22 %. Etelä-Karjalan energiatalouden tulevaisuuteen vaikuttaa merkittävästi maakunnan metsäteollisuuden tulevaisuus. Tiukentuvan energia- ja ilmastopolitiikan ja ympäristömääräysten myötä maakunnan energiatehokkuutta on parannettava kaikilla sektoreilla. Maakunnan energiankulutusta voidaan vähentää tehostamalla energiantuotantoa, tiivistämällä yhdyskuntarakennetta ja lisäämällä bioenergian käyttöä energiantuotannossa. Etelä-Karjalassa on myös potentiaalia lisätä vaihtoehtoisten energialähteiden osuutta maakunnan energiatalouden tulevaisuudessa.

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Yritysten vastuullisuudesta on tullut yhä tärkeämpi aihe sekä länsimaalaisille kuluttajille että yrityksille itselleen. Tämän tutkielman aiheeksi valikoituikin yritysten ympäristövastuu ja -raportointi sekä ympäristöraportoinnin laatu. Tutkielman teoriaosuudessa tarkastellaan lähemmin yritysten ympäristöraportointia sekä hieman sen taustalla vaikuttavaa ympäristövastuuta. Ympäristöraportoinnin kohdalla tutkitaan, kuinka ympäristöraportointia on säädelty. Lähemmän tarkastelun kohteena ovat lakisääteinen ympäristöraportointi, GRI -raportointiohjeisto sekä Global Compact toimintaperiaate. Tutkielman empiriaosuudessa puolestaan tutkitaan, kuinka suuret suomalaiset paperiteollisuusyhtiöt ovat noudattaneet teoriaosuudessa tarkasteltuja ympäristöraportoinnin säätelyjä. Empirian tavoitteena onkin saada vastaus tutkielman tutkimusongelmaan: ”Kuinka laadukkaasti suuret suomalaiset paperiteollisuusyritykset raportoivat ympäristöasioistaan?”.

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Local features are used in many computer vision tasks including visual object categorization, content-based image retrieval and object recognition to mention a few. Local features are points, blobs or regions in images that are extracted using a local feature detector. To make use of extracted local features the localized interest points are described using a local feature descriptor. A descriptor histogram vector is a compact representation of an image and can be used for searching and matching images in databases. In this thesis the performance of local feature detectors and descriptors is evaluated for object class detection task. Features are extracted from image samples belonging to several object classes. Matching features are then searched using random image pairs of a same class. The goal of this thesis is to find out what are the best detector and descriptor methods for such task in terms of detector repeatability and descriptor matching rate.

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O presente trabalho teve por objetivo avaliar o comportamento da canafistula (Peltophorumdubium), em semeadura direta a campo, em área de capoeira originada após o abandono do local utilizado com cultivos agrícolas sucessivos. No local foram roçadas faixas de 1,5 m, a cada 3 m. A semeadura foi realizada em setembro de 1997. Visando proteger os pontos semeados, foram utilizados diferentes tipos de protetores (copos de plástico e copos de papel, sem fundo e laminado de madeira), fixados sobre os pontos semeados com três sementes cada. As sementes foram escarificadas mecanicamente a 1.725 rpm, durante 60 segundos, com lixa Norton 60. O delineamento foi em blocos casualizados, com seis repetições. As variáveis avaliadas foram emergência, sobrevivência, número de pontos com plantas, densidade a 1 ano e altura das plantas aos 18 meses. Os resultados obtidos aos nove meses demonstraram que a utilização de qualquer um dos protetores físicos contribuiu para o estabelecimento de plantas em mais de 80% dos pontos semeados, e em mais de 75%, um ano após a semeadura, quando utilizado o laminado, o que indica que a semeadura direta é uma alternativa de implantação para a espécie, possibilitando transformar as áreas de capoeiras em um sistema agroflorestal ou mesmo silvipastoril, no futuro.

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Hehkulamput tullaan kieltämään Euroopan Unionin alueella vuoden 2016 syyskuuhun mennessä. Hehkulamput korvataan suurimmaksi osaksi pienloistelampuilla, jotka omaavat hehkulamppuihin verrattuna paremman hyötysuhteen. Pienloistelamput aiheuttavat kuitenkin häiriöitä niitä syöttävään sähköverkkoon. Tässä kandidaatin työssä mitattiin 15 erilaisen pienloistelampun aiheuttamat johtuvat RF-taajuiset häiriöt. Tuloksia verrattiin CISPR 15 – standardissa esitettyihin raja-arvoihin, joita pienloistelamppujen tulisi noudattaa. Mittaukset suoritettiin käyttämällä CISPR 16 –standardin kanssa yhteensopivaa mittavastaanotinta (Rohde & Schwarz ESHS30) sekä myöskin CISPR 16 yhteensopivaa keinoverkkoa (Rohde & Schwarz ESH2Z5). Lamput mitattiin CISPR 15 –standardin mukaisesti, muutamia poikkeuksia lukuun ottamatta. Lamppuja ei mitattu käyttämällä CISPR 15 –standardissa vaadittua lampun pidintä. Eikä lamppuja myöskään esikäytetty ollenkaan. Lukuun ottamatta yhtä pienloistelamppua, kaikki jäivät raja-arvon alapuolelle. Rajan ylittäneen lampun tulos tosin mahtuu mittavastaanottimen mittavirheeseen. Joten kyseessä ei ollut suuren suuri ylitys. Muiden tutkittujen pienloistelamppujen johtuvat RF-häiriöt ovat hyväksyttävällä tasolla ja ne tuskin tulevat aiheuttamaan ongelmia.

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One of the targets of the climate and energy package of the European Union is to increase the energy efficiency in order to achieve a 20 percent reduction in primary energy use compared with the projected level by 2020. The energy efficiency can be improved for example by increasing the rotational speed of large electrical drives, because this enables the elimination of gearboxes leading to a compact design with lower losses. The rotational speeds of traditional bearings, such as roller bearings, are limited by mechanical friction. Active magnetic bearings (AMBs), on the other hand, allow very high rotational speeds. Consequently, their use in large medium- and high-speed machines has rapidly increased. An active magnetic bearing rotor system is an inherently unstable, nonlinear multiple-input, multiple-output system. Model-based controller design of AMBs requires an accurate system model. Finite element modeling (FEM) together with the experimental modal analysis provides a very accurate model for the rotor, and a linearized model of the magneticactuators has proven to work well in normal conditions. However, the overall system may suffer from unmodeled dynamics, such as dynamics of foundation or shrink fits. This dynamics can be modeled by system identification. System identification can also be used for on-line diagnostics. In this study, broadband excitation signals are adopted to the identification of an active magnetic bearing rotor system. The broadband excitation enables faster frequency response function measurements when compared with the widely used stepped sine and swept sine excitations. Different broadband excitations are reviewed, and the random phase multisine excitation is chosen for further study. The measurement times using the multisine excitation and the stepped sine excitation are compared. An excitation signal design with an analysis of the harmonics produced by the nonlinear system is presented. The suitability of different frequency response function estimators for an AMB rotor system are also compared. Additionally, analytical modeling of an AMB rotor system, obtaining a parametric model from the nonparametric frequency response functions, and model updating are discussed in brief, as they are key elements in the modeling for a control design. Theoretical methods are tested with a laboratory test rig. The results conclude that an appropriately designed random phase multisine excitation is suitable for the identification of AMB rotor systems.

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Kirjallisuusarvostelu

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Software systems are expanding and becoming increasingly present in everyday activities. The constantly evolving society demands that they deliver more functionality, are easy to use and work as expected. All these challenges increase the size and complexity of a system. People may not be aware of a presence of a software system, until it malfunctions or even fails to perform. The concept of being able to depend on the software is particularly significant when it comes to the critical systems. At this point quality of a system is regarded as an essential issue, since any deficiencies may lead to considerable money loss or life endangerment. Traditional development methods may not ensure a sufficiently high level of quality. Formal methods, on the other hand, allow us to achieve a high level of rigour and can be applied to develop a complete system or only a critical part of it. Such techniques, applied during system development starting at early design stages, increase the likelihood of obtaining a system that works as required. However, formal methods are sometimes considered difficult to utilise in traditional developments. Therefore, it is important to make them more accessible and reduce the gap between the formal and traditional development methods. This thesis explores the usability of rigorous approaches by giving an insight into formal designs with the use of graphical notation. The understandability of formal modelling is increased due to a compact representation of the development and related design decisions. The central objective of the thesis is to investigate the impact that rigorous approaches have on quality of developments. This means that it is necessary to establish certain techniques for evaluation of rigorous developments. Since we are studying various development settings and methods, specific measurement plans and a set of metrics need to be created for each setting. Our goal is to provide methods for collecting data and record evidence of the applicability of rigorous approaches. This would support the organisations in making decisions about integration of formal methods into their development processes. It is important to control the software development, especially in its initial stages. Therefore, we focus on the specification and modelling phases, as well as related artefacts, e.g. models. These have significant influence on the quality of a final system. Since application of formal methods may increase the complexity of a system, it may impact its maintainability, and thus quality. Our goal is to leverage quality of a system via metrics and measurements, as well as generic refinement patterns, which are applied to a model and a specification. We argue that they can facilitate the process of creating software systems, by e.g. controlling complexity and providing the modelling guidelines. Moreover, we find them as additional mechanisms for quality control and improvement, also for rigorous approaches. The main contribution of this thesis is to provide the metrics and measurements that help in assessing the impact of rigorous approaches on developments. We establish the techniques for the evaluation of certain aspects of quality, which are based on structural, syntactical and process related characteristics of an early-stage development artefacts, i.e. specifications and models. The presented approaches are applied to various case studies. The results of the investigation are juxtaposed with the perception of domain experts. It is our aspiration to promote measurements as an indispensable part of quality control process and a strategy towards the quality improvement.

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The 'Niagara Rosada' grape is the main Brazilian table grape belonging to the Labrusca family. It develops medium, cylindrical and compact bunches with berries presenting a pinkish skin and a foxy flavor that is valued in the Brazilian market. These berries are tender and have a pedicel-berry connection provided by the vascular bundles and surrounding skin. This cultivar is very susceptible to berry drop mainly caused by vibration and senescence. The objective of this study was to evaluate the temporal mechanical behavior of the pedicel-berry detachment, using resistance indexes extracted from traction force-deformation curves. Test results showed two different detachment types. In the first one, which exhibited higher average resistance, a considerable portion of the vascular bundle came out attached to the pedicel and in the second type; the vascular bundle was retained inside the berry. The proposed indexes based on maximum detachment force, force at 0.2; 0.5; 1.0 and 1.2 mm, and maximum force to corresponding deformation ratio did not discriminate the senescence of the berry.

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The spatial distribution of illuminance and the electric consumption of artificial lighting system is one of the main problems related to broiler production. Therefore, the aim of this study was to evaluate the spatial distribution of luminance level and energy efficiency of different lighting systems for broiler houses. Six types of lamps were tested in two different configurations to find the minimum illuminance of 20 and 5 lux. The tested lamps were incandescent (IL) 100 W, compact fluorescent (CFL) 34 W, mixed (ML) 160 W, sodium vapor (SVL) 70 W, T8 fluorescent tube (T8 FTL) 40 W and T5 fluorescent tube (T5 FTL) 28 W. The first four were evaluated with and without reflective light fixture and the latter two without light fixture. It was observed that the tested system with light fixtures negatively affected the spatial distribution of illuminance inside the house. The systems composed by IL and ML without light fixture led to better results in meeting the minimum illuminance of 20 lux and 5 lux, respectively. T5 FTL presented the lowest energy demand.

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The aim of this study was to develop a an automated bench top electronic penetrometer (ABEP) that allows performing tests with high rate of data acquisition (up to 19,600 Hz) and with variation of the displacement velocity and of the base area of cone penetration. The mechanical components of the ABEP are: a supporting structure, stepper motor, velocity reducer, double nut ball screw and six penetration probes. The electronic components of ABEP are: a "driver" to control rotation and displacement, power supply, three load cells, two software programs for running and storing data, and a data acquisition module. This penetrometer presented in compact size, portable and in 32 validation tests it proved easy to operate, and showed high resolution, high velocity in reliability in data collection. During the validation tests the equipment met the objectives, because the test results showed that the ABEP could use different sizes of cones, allowed work at different velocities, showed for velocity and displacement, were only 1.3% and 0.7%, respectively, at the highest velocity (30 mm s-1) and 1% and 0.9%, respectively for the lowest velocity (0.1 mm s-1).