958 resultados para transmission grid


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Few data are available in the literature concerning the efficacy of standard hysteroscope disinfection procedures to prevent hepatitis B transmission. The aim of the present study was to determine the risk of hepatitis B virus (HBV) transmission during hysteroscopy among anti-HBc-seropositive women. Serum and hysteroscopic samples were collected from 62 women after diagnostic hysteroscopy. All samples were tested for serologic HBV markers. Polymerase chain reactions (PCR) were carried out to amplify regions C and S of the viral genome and only samples amplified by both pairs of primers were considered to be positive. Anti-HBc was repeatedly reactive in 48 (77%) of 62 serum samples, and HBsAg was detected in 8 (13%). At least one HBV serologic marker was found in 49 (79%) samples. Only one sample was HBsAg positive and anti-HBc negative. HBV-DNA was detected by PCR in 7 serum samples but in only 3 hysteroscopic samples obtained just after hysteroscopy. It is noteworthy that high levels of anti-HBc IgM were detected in one HBsAg-negative patient who showed an HBV-DNA-positive hysteroscopic sample. An elevated sample/cut-off ratio for anti-HBc IgM suggests recent infection and reinforces the need for testing for HBsAg and anti-HBc before hysteroscopy, since acute hepatitis B can be clinically asymptomatic. Viral DNA was not detected in any hysteroscopic samples collected after washing and disinfecting procedures with glutaraldehyde. We conclude that HBV-DNA can be found in the hysteroscope soon after hysteroscopy, but standard disinfecting procedures are effective in viral removal.

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Social enterprises apply the best of business for the pursuit of social or environmental mission while also generating revenues. Globally, nearly 1,3 billion people lack access to electricity, as well as another billion having access to only low quality and infrequent electricity. Off-grid renewable energy, like solar, will increasingly have a key role in the solution of the energy access issue. The pioneer gap in off-grid renewable energy consists of financing (or funding) gaps and capacity gaps, to do with both the early stage of the enterprises in question, as well as the early stage of the whole industry. The gaps are emphasised by specific characteristics of off-grid renewable energy business models and the requirements of operating in bottom-of-the-pyramid markets. The marketing perspective to fundraising is chosen to uncover the possible role enterprises themselves have in bridging the pioneer gap. The purpose of this thesis is to study how social enterprises operating in off-grid renewable energy in Africa utilise marketing activities in their investor relations in bridging the pioneer gap. This main research question is divided into the following sub-questions:  How does the pioneer gap affect fundraising for these enterprises?  How are the funding needs for these enterprises characterised?  How do these enterprises build trust in their investor relations? The theoretic framework is built on relationship marketing and investor relations, with an emphasis on creation of trust. The research is conducted as a thematical case study. Primary data is gathered via semi-structured interviews with six solar energy companies and two accelerators. According to the findings, the main components affecting trust-creation are diminished information asymmetry and perceived risk, mission alignment as well as a personal fit or relationship with the investor. Therefore, an enterprise can utilise e.g. the following marketing activities in their investor relations to bridge the pioneer gap: ensuring investor material, the enterprise story and presenting of them is clear, concise and complete to “package” the enterprise as an investment; taking investor needs and motivations into account as well as utilising existing investors as ambassadors.

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Tässä työssä tutkitaan asiakaslähtöisyyttä tuotekehityksessä ja piilevien asiakastarpeiden selvittämistä ja hyödyntämistä asiakaslähtöisyydessä. Tavoitteena on selvittää asiakaslähtöisyyden tärkeyttä ja etuja tuotekehityksessä, sekä käydä läpi erilaisia asiakastarpeiden selvittämismetodeja erityisesti keskittyen repertory grid –tekniikkaan (RGT). Asiakaslähtöisyys tuo yrityksille merkittävää kilpailuetua tuotekehityksen alkupäähän. Erityisesti piilevät asiakastarpeet voivat mahdollistaa tuoteinnovaatioita, joilla saavutetaan huomattavasti parempaa asiakastyytyväisyyttä ja etulyöntiasemaa kilpailijoihin nähden. Piileviä asiakastarpeita voi tunnistaa repertory grid –tekniikalla, jota on avattu tässä työssä. Tekniikka mahdollistaa piilevien asiakastarpeiden tunnistamisen, mikä osaltaan edistää etulyöntiaseman antavia asiakaslähtöisiä tuoteinnovaatioita, joilla yritys voi differoitua muista markkinoilla olevista yrityksistä. Asiakaslähtöisyyden tulee tuotekehityksen lähtökohdan lisäksi olla osa yrityksen strategiaa ja kulttuuria, jotta yritys voi menestyä asiakaslähtöisyydellä.

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The objective of this study was to investigate the occurrence of vancomycin-resistant Enterococcus (VRE) cross-transmission between two patient groups (long-term dialysis and kidney transplant patients). Molecular typing, by automated ribotyping with the RiboPrinter Microbial Characterization System (Qualicon, USA), was used to analyze VRE isolates from 31 fecal samples of 320 dialysis patients and 38 fecal samples of 280 kidney transplant patients. Clonal spread of E. faecalis and E. casseliflavus was observed intragroup, but not between the two groups of patients. In turn, transmission of E. gallinarum and E. faecium between the groups was suggested by the finding of vancomycin-resistant isolates belonging to the same ribogroup in both dialysis and transplant patients. The fact that these patients were colonized by VRE from the same ribogroup in the same health care facility provides evidence for cross-transmission and supports the adoption of stringent infection control measures to prevent dissemination of these bacteria.

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The aim of this study was to determine the effects of intermittent passive manual stretching on various proteins involved in force transmission in skeletal muscle. Female Wistar weanling rats were randomly assigned to 5 groups: 2 control groups containing 21- and 30-day-old rats that received neither immobilization nor stretching, and 3 test groups that received 1) passive stretching over 3 days, 2) immobilization for 7 days and then passive stretching over 3 days, or 3) immobilization for 7 days. Maximal plantar flexion in the right hind limb was imposed, and the stretching protocol of 10 repetitions of 30 s stretches was applied. The soleus muscles were harvested and processed for HE and picrosirius staining; immunohistochemical analysis of collagen types I, III, IV, desmin, and vimentin; and immunofluorescence labeling of dystrophin and CD68. The numbers of desmin- and vimentin-positive cells were significantly decreased compared with those in the control following immobilization, regardless of whether stretching was applied (P<0.05). In addition, the semi-quantitative analysis showed that collagen type I was increased and type IV was decreased in the immobilized animals, regardless of whether the stretching protocol was applied. In conclusion, the largest changes in response to stretching were observed in muscles that had been previously immobilized, and the stretching protocol applied here did not mitigate the immobilization-induced muscle changes. Muscle disuse adversely affected several proteins involved in the transmission of forces between the intracellular and extracellular compartments. Thus, the 3-day rehabilitation period tested here did not provide sufficient time for the muscles to recover from the disuse maladaptations in animals undergoing postnatal development.

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The liberalisation of the wholesale electricity markets has been considered an efficient way to organise the markets. In Europe, the target is to liberalise and integrate the common European electricity markets. However, insufficient transmission capacity between the market areas hampers the integration, and therefore, new investments are required. Again, massive transmission capacity investments are not usually easy to carry through. This doctoral dissertation aims at elaborating on critical determinants required to deliver the necessary transmission capacity investments. The Nordic electricity market is used as an illustrative example. This study suggests that changes in the governance structure have affected the delivery of Nordic cross-border investments. In addition, the impacts of not fully delivered investments are studied in this doctoral dissertation. An insufficient transmission network can degrade the market uniformity and may also cause a need to split the market into smaller submarkets. This may have financial impacts on market actors when the targeted efficient sharing of resources is not met and even encourage gaming. The research methods applied in this doctoral dissertation are mainly empirical ranging from a Delphi study to case studies and numerical calculations.

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Recent Storms in Nordic countries were a reason of long power outages in huge territories. After these disasters distribution networks' operators faced with a problem how to provide adequate quality of supply in such situation. The decision of utilization cable lines rather than overhead lines were made, which brings new features to distribution networks. The main idea of this work is a complex analysis of medium voltage distribution networks with long cable lines. High value of cable’s specific capacitance and length of lines determine such problems as: high values of earth fault currents, excessive amount of reactive power flow from distribution to transmission network, possibility of a high voltage level at the receiving end of cable feeders. However the core tasks was to estimate functional ability of the earth fault protection and the possibility to utilize simplified formulas for operating setting calculations in this network. In order to provide justify solution or evaluation of mentioned above problems corresponding calculations were made and in order to analyze behavior of relay protection principles PSCAD model of the examined network have been created. Evaluation of the voltage rise in the end of a cable line have educed absence of a dangerous increase in a voltage level, while excessive value of reactive power can be a reason of final penalty according to the Finish regulations. It was proved and calculated that for this networks compensation of earth fault currents should be implemented. In PSCAD models of the electrical grid with isolated neutral, central compensation and hybrid compensation were created. For the network with hybrid compensation methodology which allows to select number and rated power of distributed arc suppression coils have been offered. Based on the obtained results from experiments it was determined that in order to guarantee selective and reliable operation of the relay protection should be utilized hybrid compensation with connection of high-ohmic resistor. Directional and admittance based relay protection were tested under these conditions and advantageous of the novel protection were revealed. However, for electrical grids with extensive cabling necessity of a complex approach to the relay protection were explained and illustrated. Thus, in order to organize reliable earth fault protection is recommended to utilize both intermittent and conventional relay protection with operational settings calculated by the use of simplified formulas.

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Wind turbines based on doubly fed induction generators (DFIG) become the most popular solution in high power wind generation industry. While this topology provides great performance with the reduced power rating of power converter, it has more complicated structure in comparison with full-rated topologies, and therefore leads to complexity of control algorithms and electromechanical processes in the system. The purpose of presented study is to present a proper vector control scheme for the DFIG and overall control for the WT to investigate its behavior at different wind speeds and in different grid voltage conditions: voltage sags, magnitude and frequency variations. The key principles of variable-speed wind turbine were implemented in simulation model and demonstrated during the study. Then, based on developed control scheme and mathematical model, the set of simulation is made to analyze reactive power capabilities of the DFIG wind turbine. Further, the rating of rotor-side converter is modified to not only generate active rated active power, but also to fulfill Grid Codes. Results of modelling and analyzing of the DFIG WT behavior under different speeds and different voltage conditions are presented in the work.

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Aims: The aim of this work was to assess the ultrastructural changes, cellular proliferation, and the biofilm formation ability of F. nucleatum as defense mechanisms against the effect of HNP-1. Materials and methods: The type strain of F. nucleatum (ssp. nucleatum ATCC 25586) and two clinical strains (ssp. polymorphum AHN 9910 and ssp. nucleatum AHN 9508) were cultured and incubated with four different test concentrations of recombinant HNP-1 (1, 5, 10 and 20 µg/ml) and one control group (0 µg/ml). Bacterial pellets from each concentration were processed for TEM imaging. Planktonic growth was assessed and colony forming units (CFU) were measured to determine the cellular proliferation. Scrambled HNP-1 was used for confirmation. Results: TEM analyses revealed a decrease in the outer membrane surface corrugations and roughness of the strain AHN 9508 with increasing HNP-1 concentrations. In higher concentrations of HNP-1, the strain AHN 9910 showed thicker outer membranes with a number of associated rough vesicles attached to the outer surface. For ATCC 25586, the treated bacterial cells contained higher numbers of intracellular granules with increasing the peptide concentration. Planktonic growth of the two clinical strains were significantly enhanced (P<0.001) with gradually increased concentrations of HNP-1. None of the planktonic growth results of the 3 strains incubated with the scrambled HNP-1 was statistically significant. HNP-1 decreased the biofilm formation of the two clinical strains, AHN 9910 and 9508, significantly (P<0.01 and P<0.001; respectively). Conclusions: The present in vitro study demonstrates that F. nucleatum has the ability to withstand the lethal effects of HNP-1 even at concentrations simulating the diseased periodontium in vivo. The increase in planktonic growth could act as defense mechanisms of F. nucleatum against HNP-1.

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Kuitukomposiitista valmistettuja juurikanavanastoja käytetään apuna, kun restauroidaan juurihoidettuja ja kruunuosastaan runsaasti kudosta menettäneitä hampaita. Kliinisen kestävyyden kannalta on tärkeää että nasta kiinnittyy hampaaseen hyvin. Tarvittavan valomäärän saattaminen valokovetuksella pimeään juurikanavaan on vaikeaa ja sen vuoksi nastojen kiinnittämiseen suositellaan kaksoiskovetteista yhdistelmämuovisementtiä, joka kovettuu vain osittain valolla. Jotta nasta ja sementti polymeroituisivat hyvin, nastan hyvä valonläpäisy- ja sirontakyky olisi eduksi. Tehdasvalmisteisten nastojen valonläpäisykyvyn on todettu heikkenevän niiden pituuden kasvaessa. Yksilöllisesti muotoilluilla kuitukomposiittinastoilla, joilla on osittaislomittaismuoviverkostorakenne (semi-IPN) polymeerimatriisi, on todettu tehdasvalmisteisia kuitunastoja parempi sidos nastan ja yhdistelmämuovisementin välillä. Yksilöllisesti muotoilluilla kuitunastoilla näyttäisi myös olevan hyvä valonjohtamiskyky, mutta lisätutkimuksia tarvitaan. Tässä tutkimuksessa selvitettiin yksilöllisesti muotoillun kuitukomposiittinastan (EverStick Post) ja kahden tehdasvalmisteisen (Relyx Fiber Post ja GC Fiber Post) kuitukomposiittina stan valonläpäisevyyttä sekä pituuden vaikutusta niiden valonläpäisykykyyn laboratorio- olosuhteissa. Tutkimushypoteesi oli, että nastojen valonläpäisykyky heikkenee niiden pidentyessä. Tutkimuksessa kaikista nastatyypeistä valmistettiin eripituisia nastoja (4, 8, 12 ja 16 mm). Nastoille tehtiin samanpituiset testikappaleet muoviputkesta ja polyvinyylisiloksaanista, ja nastat asetettiin niiden sisään. Tämän jälkeen nastoja kovetettiin valokovettimella 10 sekuntia, ja läpi päässyt valo mitattiin MARC Resin Calibrator -laitteella. Kontrollina käytettiin tyhjää testikappaletta ilman nastaa. Keskeiseksi tulokseksi saatiin, että yksilöllisesti muotoillulla kuitukomposiittinastalla oli kaikissa pituusryhmissä muita nastoja merkitsevästi parempi valonläpäisykyky. Tulokset osoittivat myös, että kaikkien nastojen valonläpäisevyys laski merkitsevästi nastan pituuden lisääntyessä aina 12 millimetriin asti. Tulosten perusteella yksilöllisesti muotoillulla kuitukomposiittinastalla on tehdasvalmisteista nastaa parempi valonläpäisykyky. Kuitukomposiittinastojen valonläpäisykyky heikkenee niiden pituuden kasvaessa aiempien tutkimusten mukaisesti. Jatkotutkimuksissa tulisi selvittää, miten valonläpäisevyys ja siroaminen vaikuttavat nastan ja sementin polymeroitumiseen ja siten kliiniseen lopputulokseen.

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This project aims to design and manufacture a mobile robot with two Universal Robot UR10 mainly used indoors. In order to obtain omni-directional maneuverability, the mobile robot is constructed with Mecanum wheels. The Mecanum wheel can move in any direction with a series of rollers attached to itself. These rollers are angled at 45º about the hub’s circumference. This type of wheels can be used in both driving and steering with their any-direction property. This paper is focused on the design of traction system and suspension system, and the velocity control of Mecanum wheels in the close-loop control system. The mechanical design includes selection of bearing housing, couplers which are act as connection between shafts, motor parts, and other needed components. The 3D design software SolidWorks is utilized to assemble all the components in order to get correct tolerance. The driving shaft is designed based on assembled structure via the software as well. The design of suspension system is to compensate the assembly error of Mecanum wheels to guarantee the stability of the robot. The control system of motor drivers is realized through the Robot Operating System (ROS) on Ubuntu Linux. The purpose of inverse kinematics is to obtain the relationship among the movements of all Mecanum wheels. Via programming and interacting with the computer, the robot could move with required speed and direction.

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Tässä kandidaatintyössä selvitetään kirjallisuustutkimuksena sähkön yleissiirtohinnat Suomessa vuonna 2015. Työssä vertaillaan sähkön siirtohintoja erilaisilla kotitalouskuluttajilla ja tutkitaan sähkönsiirron hinnoitteluun vaikuttavia tekijöitä. Työssä esitetään myös tulevaisuudessa mahdollisesti käytettäviä siirtotariffeja. Työ tuo esiin sähkön siirtohinnan komponenttien osuudet sähkönsiirron kokonaishinnasta, sekä havainnollistaa visuaalisesti komponenttien maantieteellistä vaihtelua. Siirtomaksujen vaihtelua erilaisilla kulutuksilla havainnollistetaan käyttämällä kolmea esimerkkikuluttajaa, sekä vertailemalla esimerkkikuluttajien siirtomaksuja keskenään. Siirtomaksujen kokonaiskustannusten maantieteellistä vaihtelua havainnollistetaan kuvien avulla. Energiaviraston regulaation vaikutuksia siirtohintaan tarkastellaan verkkoyhtiöiden yli- ja alijäämien avulla. Tulevaisuuden siirtotariffeista huomio kiinnittyy kaistahinnoitteluun. Kaistahinnoittelua tarkastellaan kuluttajan kannalta ja samalla tuodaan esiin kaistahinnoittelun etuja nykyisin käytössä oleviin siirtotariffeihin. Työn perusteella voidaan tehdä johtopäätös, että sähkön kulutuksen kasvaessa siirtomaksu kulutettua energiayksikköä kohden pienenee. Toisin sanoen perusmaksun osuus on merkittävä pienillä kulutusmäärillä ja sen suhteellinen osuus siirtomaksuista pienenee kulutuksen kasvaessa.

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The objective of this study was to identify the fungi associated with the fruit and seeds of Blepharocalyx salicifolius and verify their transmission and pathogenicity to seeds and seedlings. Fungal identification on seeds was made using the blotter test and potato-dextrose-agar but only the blotter test was used for fruit. Fungal transmission to seedlings was evaluated using four replications of 50 seeds planted in vermiculite. The pathogenicity of the fungi, Colletotrichum sp., Curvularia sp., Cladosporium sp. Pestalotia sp. and Macrophomina sp. was tested. Potentially pathogenic and saprophytic fungi were found on the fruits and seeds. The transmission of Cladosporium sp. from seeds to seedlings was verified, and Cladosporium sp. Pestalotia sp. and Macrophomina sp. were found to be pathogenic to B. salicifolius seedlings.

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Hammaslääketieteessä käytetettävien komposiittien valonläpäisevyys vaihtelee. Samoin LED-valokovettimet eroavat toisistaan valotehonsa ja muotoilunsa perusteella. On yleisesti tiedossa, että valokovettimesta tulevan valon intensiteetti pinta-alayksikköä kohden heikkenee, kun kovettimen etäisyys kasvaa. Toisaalta ei ole tiedossa, miten valokovetettavan kohteen ja valokovettimen kärjen väliin sijoitettu materiaali tarkalleenottaen vaikuttaa valon intensiteettiin eri etäisyyksiä käytettäessä. Tämän tutkimuksen tarkoituksena on selvittää, miten valokovetettavan kohteen ja valokovettimen kärjen väliin asetettava etukäteen polymerisoitu materiaali vaikuttaa valon intensiteettiin eri etäisyyksillä. Tutkimus suoritettiin käyttämällä kahta eri valokovetinta. Jotta etäisyyden vaikutusta valotustehoon voitiin demonstroida, vaihdettiin kovettimen etäisyyttä sensorista 0,2,4,6,8,10mm välillä. Valotehot rekisteröitiin MARC resin calibrator -laitteella. Sensorin ja valokovettimen kärjen väliin asetettavat erilaiset komposiittilevyt olivat valmiiksi kovetettuja,1mm paksuisia, filleripitoisuuksiltaan neljää erilaista muovia. Valotehot rekisteröitiin jokaiselta etäisyydeltä komposiitin ollessa sensorin päällä. Rinnakkaisesti verrattiin myös etäisyyden vaikutusta valotehoon ilman esikovetettua materiaalia kovettimen kärjen ja valoa mittaavan sensorin välissä. Vertailun suorittamiseksi laskettiin intensiteettisuhdeluku muovillisen ja muovittoman arvon välillä aina tietyllä etäisyydellä Valokovettimen kärjen etäisyyden kasvattaminen sensorista (eli valokovetettavasta kohteesta) odotusten mukaisesti pienensi valotehoa. Laittamalla sensorin ja kovettimen väliin komposiittilevy, valoteho pieneni odotetusti vielä enemmän. Tutkittaessa intensiteettisuhdetta (valoteho muovin kanssa : valoteho ilman muovia) kuitenkin huomattiin, että 4-6mm:n kohdalla suhdeluku oli suurempi kuin 0,2,8 ja 10mm kohdalla. Johtopäätöksenä oli, että suurin mahdollinen valokovetusteho saavutetan laittamalla kovetuskärki mahdollisimman lähelle kohdetta. Jos valokovetettavan kohteen ja valokovettimen kärjen välissä oli kiinteä komposiittipalanen, suurin mahdollinen valokovetusteho kohteeseen saavutetaan edelleen laittamalla kovetuskärki kiinni muoviin. Jos etäisyyttä muovin pinnasta sen sijaan kasvatettiin, valokovetusteho ei laskenutkaan niin nopeasti kuin oli odotettu. Tämä voi liittyä siihen, että tehokkaan valokeilan halkaisijan koko on suurempi verrattuna komposiitin sekä sensorin halkaisian kokoon. Toiseksi on arvioitu, että resiinikomposiitin täyteaineet voisivat fokusoida läpi kulkevaa valoa sensoriin. Se, pitääkö tämä ilmiö paikkansa, vaatii kuitenkin enemmän tutkimusta