An Improved Hybrid Model for the Generic Hoist Scheduling Problem

Peer-reviewed

Field performance of hybrid aspen clones planted in summer

[Abstract]

Parasitic fauna in hybrid tambacu from fish farms

The objective of this work was to evaluate the parasitic fauna of hybrid tambacu (Colossoma macropomum x Piaractus mesopotamicus) from fish farms and the host-parasite relationship. A hundred and fourteen fish were collected from four fish farms in Macapá, in the state of Amapá, Brazil, 80.7% of which were infected by: Ichthyophthirius multifiliis (Ciliophora); Piscinoodinium pillulare (Dinoflagellida); Anacanthorus spatulatus, Notozothecium janauachensis, and Mymarothecium viatorum (Monogenoidea); Neoechinorhynchus buttnerae (Acanthocephala); Cucullanus colossomi (Nematoda); Perulernaea gamitanae (Lernaeidae); and Proteocephalidae larvae (Cestoda). A total of 8,136,252 parasites were collected from the examined fish. This is the first record of N. buttnerae, C. colossomi, N. janauachensis, M. viatorum, and Proteocephalidae for hybrid tambacu in Brazil. Ichthyophthirius multifiliis was the most prevalent parasite, whereas endohelminths were the less. A positive correlation was observed between number of I. multifiliis and total length and weight of fish, as well as between number of P. gamitanae and total length. The infection by I. multifiliis had association with the parasitism by Monogenoidea. Low water quality contributes to high parasitism of hybrid tambacu by ectoparasites, which, however, does not influence the relative condition factor of fish.

Hybrid model of a double-fed induction machine and back-to-back converter

This report details the port interconnection of two subsystems: a power electronics subsystem (a back-to-back AC/AC converter (B2B), coupled to a phase of the power grid), and an electromechanical subsystem (a doubly-fed induction machine (DFIM), coupled mechanically to a flywheel and electrically to the power grid and to a local varying load). Both subsystems have been essentially described in previous reports (deliverables D 0.5 and D 4.3.1), although some previously unpublished details are presented here. The B2B is a variable structure system (VSS), due to the presence of control-actuated switches: however from a modelling and simulation, as well as a control-design, point of view, it is sensible to consider modulated transformers (MTF in the bond-graph language) instead of the pairs of complementary switches. The port-Hamiltonian models of both subsystems are presents and coupled through a power-preserving interconnection, and the Hamiltonian description of the whole system is obtained; detailed bond-graphs of all the subsystems and the complete system are provided.

ML estimator and hybrid beamformer for multipath and interference mitigation in GNSS receivers

This paper addresses the estimation of the code-phase(pseudorange) and the carrier-phase of the direct signal received from a direct-sequence spread-spectrum satellite transmitter. Thesignal is received by an antenna array in a scenario with interferenceand multipath propagation. These two effects are generallythe limiting error sources in most high-precision positioning applications.A new estimator of the code- and carrier-phases is derivedby using a simplified signal model and the maximum likelihood(ML) principle. The simplified model consists essentially ofgathering all signals, except for the direct one, in a component withunknown spatial correlation. The estimator exploits the knowledgeof the direction-of-arrival of the direct signal and is much simplerthan other estimators derived under more detailed signal models.Moreover, we present an iterative algorithm, that is adequate for apractical implementation and explores an interesting link betweenthe ML estimator and a hybrid beamformer. The mean squarederror and bias of the new estimator are computed for a numberof scenarios and compared with those of other methods. The presentedestimator and the hybrid beamforming outperform the existingtechniques of comparable complexity and attains, in manysituations, the Cramér–Rao lower bound of the problem at hand.

Hybrid turbo FEC/ARQ systems and distributed space-time coding for cooperative transmission

Cooperative transmission can be seen as a "virtual" MIMO system, where themultiple transmit antennas are in fact implemented distributed by the antennas both at the source and the relay terminal. Depending on the system design, diversity/multiplexing gainsare achievable. This design involves the definition of the type of retransmission (incrementalredundancy, repetition coding), the design of the distributed space-time codes, the errorcorrecting scheme, the operation of the relay (decode&forward or amplify&forward) and thenumber of antennas at each terminal. Proposed schemes are evaluated in different conditionsin combination with forward error correcting codes (FEC), both for linear and near-optimum(sphere decoder) receivers, for its possible implementation in downlink high speed packetservices of cellular networks. Results show the benefits of coded cooperation over directtransmission in terms of increased throughput. It is shown that multiplexing gains areobserved even if the mobile station features a single antenna, provided that cell wide reuse of the relay radio resource is possible.

Els materials arqueològics del jaciment ibèric de la Serra de l’Espasa (Capçanes, Priorat) dipositats al Museu d’Arqueologia Salvador Vilaseca de Reus: evidències d’un santuari?

En aquest treball presentem una revisió del jaciment ibèric de la Serra de l’Espasa (Capçanes, Priorat) a partir de l’estudi, amb criteris actualitzats, del material conservat en el Museu Salvador Vilaseca de Reus. Els resultats són contrastats amb les darreres investigacions arqueològiques desenvolupades en el curs inferior de l’Ebre. A l’últim, s’analitzen les possibles interpretacions d’aquest conjunt, en particular la hipotètica existència d’un santuari, i les seves implicacions en el procés de romanització en aquesta zona.

Nou portal d'accés als materials en obert de la UdG : DUGi 2.0

La Biblioteca de la Universitat de Girona és l'encarregada de coordinar els repositoris digitals de la Universitat. A l'inici el repositori neix de la necessitat de difondre i preservar tota la recerca de la Universitat, però mica en mica el projecte va creixent i es creen diferents repositoris per a diferents tipus de continguts. Així es creen els repositoris DUGiDocs, DUGiMedia i DUGiFonsEspecials.L'objectiu d'aquest PFC és desenvolupar un portal web amb un sistema d'indexació que permeti la cerca per diferents criteris com, per exemple, autor, matèria i títol. L'entorn ha de tenir un disseny agradable per a l'usuari final i ha de permetre obtenir les dades del repositori que se li indiquin. També ha de ser capaç de detectar els possibles duplicats en els criteris de cerca i notificar-ho a l'administrador

Visual measurement of laser-arc hybrid welding

Tässä työssä raportoidaan hybridihitsauksesta otettujen suurnopeuskuvasarjojen automaattisen analyysijärjestelmän kehittäminen.Järjestelmän tarkoitus oli tuottaa tietoa, joka avustaisi analysoijaa arvioimaan kuvatun hitsausprosessin laatua. Tutkimus keskittyi valokaaren taajuuden säännöllisyyden ja lisäainepisaroiden lentosuuntien mittaamiseen. Valokaaria havaittiin kuvasarjoista sumean c-means-klusterointimenetelmän avullaja perättäisten valokaarien välistä aikaväliä käytettiin valokaaren taajuuden säännöllisyyden mittarina. Pisaroita paikannettiin menetelmällä, jossa yhdistyi pääkomponenttianalyysi ja tukivektoriluokitin. Kalman-suodinta käytettiin tuottamaan arvioita pisaroiden lentosuunnista ja nopeuksista. Lentosuunnanmääritysmenetelmä luokitteli pisarat niiden arvioitujen lentosuuntien perusteella. Järjestelmän kehittämiseen käytettävissä olleet kuvasarjat poikkesivat merkittävästi toisistaan kuvanlaadun ja pisaroiden ulkomuodon osalta, johtuen eroista kuvaus- ja hitsausprosesseissa. Analyysijärjestelmä kehitettiin toimimaan pienellä osajoukolla kuvasarjoja, joissa oli tietynlainen kuvaus- ja hitsausprosessi ja joiden kuvanlaatu ja pisaroiden ulkomuoto olivat samankaltaisia, mutta järjestelmää testattiin myös osajoukon ulkopuolisilla kuvasarjoilla. Testitulokset osoittivat, että lentosuunnanmääritystarkkuus oli kohtuullisen suuri osajoukonsisällä ja pieni muissa kuvasarjoissa. Valokaaren taajuuden säännöllisyyden määritys oli tarkka useammassa kuvasarjassa.

Hitsausmenetelmät ja niiden kehittämismahdollisuudet painelaitteiden valmistuksessa

Työn tavoitteena oli painelaitteiden hitsaustuotannon kehittäminen. Keinoina olivat käytössä olevien hitsausprosessienkehittäminen tai niiden käytön tehostaminen ja mahdollisesti muiden hitsausprosessien, kuten plasma-, laser- tai hybridihitsauksen, käyttöönotto. Työn teoriaosassa käsiteltiin painelaitteiden valmistuksessa käytettävät hitsausprosessit ja niiden kehittämiskeinot, hitsauskustannuksen muodostuminen sekä miten näihin kustannuksiin voidaan vaikuttaa. Lisäksi tarkasteltiin painelaitteiden valmistuksessa käytettävien materiaalien hitsattavuutta ja laadunvarmistusta. Tutkimusosuudessa käytiin läpi valmistuksen nykytila ja tehtiin tuotannon analysointi kehittämiskohteeksi valitulle lämmönsiirtimelle. Kehitysehdotuksenatuotannon tehostamiseksi ehdotettiin MAG-täytelanka- ja jauhekaarihitsauksen käytön lisäämistä. Lisäksi ehdotettiin juurituen käyttöä ja hitsauksen mekanisoinnin lisäämistä. Plasma- tai hybridihitsauksen käytöllä todettiin pystyttävän lyhentämään läpimenoaikoja. Ennen laitteistohankintojen tekoa täytyy tehdä lisäselvityksiä soveltuvuuden ja kannattavuuden varmistamiseksi.

Nou portal d'accés als materials en obert de la UdG : DUGi 2.0

La Biblioteca de la Universitat de Girona és l'encarregada de coordinar els repositoris digitals de la Universitat. A l'inici el repositori neix de la necessitat de difondre i preservar tota la recerca de la Universitat, però mica en mica el projecte va creixent i es creen diferents repositoris per a diferents tipus de continguts. Així es creen els repositoris DUGiDocs, DUGiMedia i DUGiFonsEspecials.L'objectiu d'aquest PFC és desenvolupar un portal web amb un sistema d'indexació que permeti la cerca per diferents criteris com, per exemple, autor, matèria i títol. L'entorn ha de tenir un disseny agradable per a l'usuari final i ha de permetre obtenir les dades del repositori que se li indiquin. També ha de ser capaç de detectar els possibles duplicats en els criteris de cerca i notificar-ho a l'administrador

Comparative study of the mandarin hybrid fruit characteristics: Nova, Murcott and Ortanique in Capão Bonito SP, Brazil

The Murcott tangor represent 20% of the tangerines trees in São Paulo State being the second more grown. Their fruits have good acceptance in the market cause of the good characteristics presented as: size, attractive internal and external color, transport resistance, high juice rate and industry potential. It is necessary to study the behavior of others varieties, in order to amplify the diversity of tangerine industry, which show suitable characteristics to the fresh fruit market and that make possible different harvest season. Many tangerine varieties, selected from the Citrus Germplasm Bank of the do Centro Avançado de Pesquisa Tecnológica do Agronegócio de Citros "Sylvio Moreira"/IAC, belong to trials carried out in 15 places in São Paulo State. The Capão Bonito area, south-west of the state, is one of this places where the Nova tangelo, the Ortanique and the Murcott tangors are showing quite good results about their fruit qualities. This paper had as an objective to compare the fruit characteristics of the Nova tangelo, the Murcott and the Ortanique tangors grafted on two rootstocks: Rangpur lime and Cleopatra mandarin. Accordingly to the gotten results, is possible to conclude that Nova and Ortanique had shown weight, width, fruit shape and juice percent, similar to the Murcott. In compliance with the harvest season, the Nova present suitable conditions to fresh fruit market in May and June. By the other hand the Murcott fruits can be harvested in July to August and the Ortanique in August to September. For this reason, is possible extend the harvest season of this mandarin-like, from two to five month, occurring inclusive in a period out of the crop at the north hemisphere.

Analysis of thermal properties of phase change materials (PCM) using differential scanning calorimeter (DSC)

Commercially available PCM RT 20, RT 27, SP 22, A17 and SP 25 A8. Were analyzed using dynamic and step method of heat flux DSC. The results of the dinamic and step method were compared with commercial valures. It was found that RT 20 & RT 27 showed good conforming of results with commercial values while SP 22 A17 & SP 25 A8 did not show conformity.

Improvement of the thermal performance of commercial freezers using phase change materials (PCM)

The aim of this work is to improve the thermal performance of commercial freezers using phase change materials (PCM) and the prove the importance of the correct PCM selection (melting temperature) for each application. To do this a vertical freezer with and without macro encapsulation PCM are used to assess the benefits of using PCM in minimizing temperature fluctuations and to maintain at the lowest possible temperature the freezer under heat of losses.