800 resultados para DISTRIBUTED STRAIN
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Video transcoding refers to the process of converting a digital video from one format into another format. It is a compute-intensive operation. Therefore, transcoding of a large number of simultaneous video streams requires a large amount of computing resources. Moreover, to handle di erent load conditions in a cost-e cient manner, the video transcoding service should be dynamically scalable. Infrastructure as a Service Clouds currently offer computing resources, such as virtual machines, under the pay-per-use business model. Thus the IaaS Clouds can be leveraged to provide a coste cient, dynamically scalable video transcoding service. To use computing resources e ciently in a cloud computing environment, cost-e cient virtual machine provisioning is required to avoid overutilization and under-utilization of virtual machines. This thesis presents proactive virtual machine resource allocation and de-allocation algorithms for video transcoding in cloud computing. Since users' requests for videos may change at di erent times, a check is required to see if the current computing resources are adequate for the video requests. Therefore, the work on admission control is also provided. In addition to admission control, temporal resolution reduction is used to avoid jitters in a video. Furthermore, in a cloud computing environment such as Amazon EC2, the computing resources are more expensive as compared with the storage resources. Therefore, to avoid repetition of transcoding operations, a transcoded video needs to be stored for a certain time. To store all videos for the same amount of time is also not cost-e cient because popular transcoded videos have high access rate while unpopular transcoded videos are rarely accessed. This thesis provides a cost-e cient computation and storage trade-o strategy, which stores videos in the video repository as long as it is cost-e cient to store them. This thesis also proposes video segmentation strategies for bit rate reduction and spatial resolution reduction video transcoding. The evaluation of proposed strategies is performed using a message passing interface based video transcoder, which uses a coarse-grain parallel processing approach where video is segmented at group of pictures level.
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This bachelor’s thesis, written for Lappeenranta University of Technology and implemented in a medium-sized enterprise (SME), examines a distributed document migration system. The system was created to migrate a large number of electronic documents, along with their metadata, from one document management system to another, so as to enable a rapid switchover of an enterprise resource planning systems inside the company. The paper examines, through theoretical analysis, messaging as a possible enabler of distributing applications and how it naturally fits an event based model, whereby system transitions and states are expressed through recorded behaviours. This is put into practice by analysing the implemented migration systems and how the core components, MassTransit, RabbitMQ and MongoDB, were orchestrated together to realize such a system. As a result, the paper presents an architecture for a scalable and distributed system that could migrate hundreds of thousands of documents over weekend, serving its goals in enabling a rapid system switchover.
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The capabilities and thus, design complexity of VLSI-based embedded systems have increased tremendously in recent years, riding the wave of Moore’s law. The time-to-market requirements are also shrinking, imposing challenges to the designers, which in turn, seek to adopt new design methods to increase their productivity. As an answer to these new pressures, modern day systems have moved towards on-chip multiprocessing technologies. New architectures have emerged in on-chip multiprocessing in order to utilize the tremendous advances of fabrication technology. Platform-based design is a possible solution in addressing these challenges. The principle behind the approach is to separate the functionality of an application from the organization and communication architecture of hardware platform at several levels of abstraction. The existing design methodologies pertaining to platform-based design approach don’t provide full automation at every level of the design processes, and sometimes, the co-design of platform-based systems lead to sub-optimal systems. In addition, the design productivity gap in multiprocessor systems remain a key challenge due to existing design methodologies. This thesis addresses the aforementioned challenges and discusses the creation of a development framework for a platform-based system design, in the context of the SegBus platform - a distributed communication architecture. This research aims to provide automated procedures for platform design and application mapping. Structural verification support is also featured thus ensuring correct-by-design platforms. The solution is based on a model-based process. Both the platform and the application are modeled using the Unified Modeling Language. This thesis develops a Domain Specific Language to support platform modeling based on a corresponding UML profile. Object Constraint Language constraints are used to support structurally correct platform construction. An emulator is thus introduced to allow as much as possible accurate performance estimation of the solution, at high abstraction levels. VHDL code is automatically generated, in the form of “snippets” to be employed in the arbiter modules of the platform, as required by the application. The resulting framework is applied in building an actual design solution for an MP3 stereo audio decoder application.
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Poster at Open Repositories 2014, Helsinki, Finland, June 9-13, 2014
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Presentation at Open Repositories 2014, Helsinki, Finland, June 9-13, 2014
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Presentation at Open Repositories 2014, Helsinki, Finland, June 9-13, 2014
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Tutkimuksen tarkoituksena oli analysoida vanhusten ympärivuorokautisen hoidon yksiköissä työskentelevien työntekijöiden työn fyysistä ja psyykkistä kuormittavuutta ja työhön liittyviä fyysisiä riskejä. Lisäksi haluttiin selvittää, millaisia vaikutuksia fyysisen kuormittavuuden vähentämistä tavoitelleella ergonomisella kehittämisinterventiolla saadaan aikaan. Tutkimuksessa hyödynnettiin Turun kaupungin vanhuspalveluissa vuosina 2010–2012 toteutuneessa ergonomisessa kehittämisinterventiossa (47 työyksikköä) kertynyttä ja vuosien 2010 ja 2012 Kunta10-kyselyn (120 työyksikköä) tuottamaa tietoa. Intervention ydin oli Työterveyslaitoksen Fyysisten riskien hallintamalli hoitoalalla -mallin käyttööotto. Käytetyt mittarit olivat seuraavat: Työn kuormitus- ja työtyytyväisyyskysely työntekijöille, asiakkaiden toimintakykyä mittaava RAVATM -indeksi, fyysistä kuormitusta ja työn riskejä mittava Care ThermometerTM-menetelmä, potilassiirtojen turvallisuusjohtamisen (PHOQS) arviointi sekä esimies- ja ergonomiavastaavien kysely. Lisäksi käytössä olivat Kunta10-kyselyn tulokset valittujen muuttujien osalta kaikista tutkimukseen osallistuvista kaupungeista sekä ympärivuorokautisen hoidon asiakkaita ja hoitohenkilöstöä kuvaavia tilastoja. Työ vanhusten ympärivuorokautisessa hoidossa on fyysisesti ja psyykkisesti kuormittavaa. Interventiotoimenpiteistä huolimatta koettu fyysinen ja psyykkinen kuormittavuus kasvoivat, tosin fyysinen psyykkistä vähemmän. Kuormittavuus vaihteli toimintamuodoittain ja ammattiryhmittäin. Fyysisesti kuormittavimmaksi työ koettiin pitkäaikaissairaanhoidossa, psyykkinen kuormitus kasvoi eniten tehostetussa palveluasumisessa. Vanhainkodit sijoittuivat näiden väliin. Lähihoitajat kokivat työnsä fyysisesti kuormittavimmaksi, kun taas sairaanhoitajien työ oli psyykkisesti lähihoitajien työtä kuormittavampaa. Ergonomiakoulutus vähensi eniten koettua fyysistä kuormittavuutta. Kehityskeskustelut ja aiempaa paremmaksi arvioitu työkyky vähensivät mutta tyytymättömyys työhön lisäsi koettua fyysistä ja psyykkistä kuormittavuutta. Työntekijöiden ikä, RAVATM -indeksi, Care ThermometerTM -mittaukset ja PHOQS-pisteet eivät olleet tilastollisesti merkitsevästi yhteydessä kuormittavuuden muutoksiin. Työn kuormittavuuden vähentäminen ja turvallisen työskentelyn edistäminen vaativat pitkäkestoista toimintaa ja hyvää johtamista erityisesti lähiesimiehiltä. Fyysisten riskien hallintamallin käyttöönotto ja ergonomiavastaavien toiminnan vakiinnuttaminen tukevat tavoitteiden saavuttamista.
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Denna avhandling handlar om metoder för att hitta begränsningar för det asymptotiska beteendet hos en förväntad uthoppstid från ett område omkring en xpunkt för processer som har normalfördelad störning. I huvudsak behandlas olika typer av autoregressiva processer. Fyra olika metoder används. En metod som använder principen för stora avvikelser samt en metod som jämför uthoppstiden med en återkomsttid ger övre begränsningar för den förväntade uthoppstiden. En martingalmetod och en metod för normalfördelade stokastiska variabler ger undre begränsningar. Metoderna har alla både förtjänster och nackdelar. Genom att kombinera de olika metoderna får man de bästa resultaten. Vi får fram gränsvärdet för det asymptotiska beteendet hos en uthoppstid för den multivariata autoregressiva processen, samt motsvarande gränsvärde för den univariata autoregressiva processen av ordning n.
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An expression plasmid (pCFA-1) carrying the cfaB gene that codes for the enterotoxigenic Escherichia coli (ETEC) fimbrial adhesin colonization factor antigen I (CFA/I) subunit was constructed and used to transform a derivative of the attenuated Salmonella typhimurium aroA vaccine strain SL3261 carrying an F'lacIq. Treatment of the transformed strain with isopropyl-ß-D-thiogalactopyranoside (IPTG) resulted in elevated in vitro expression of the CFA/I subunit. Although flagellar function and lipopolysaccharide (LPS) synthesis were similar in both the parental and the recombinant strains, spleen colonization was reduced in the recombinant strain. All BALB/c mice parenterally inoculated with the recombinant strain developed significant anti-CFA/I and anti-LPS serum antibody titers (P<0.05). Moreover, 2 of 5 mice orally inoculated with the engineered Salmonella strain developed anti-CFA/I intestinal IgA (P>0.05) while 4/5 of the same mice developed anti-LPS IgA (P<0.05). The results indicate that the vaccine strain elicited an antibody response against the bacterial host both after oral and intravenous immunization while the response against the CFA/I antigen was significant only after inoculation by the intravenous route
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A constitutive alkaline phosphatase was purified to apparent homogeneity as determined by polyacrylamide gel electrophoresis from mycelia of the wild strain 74A of the mold Neurospora crassa, after growth on acetate and in the presence of saturating amounts of inorganic phosphate (Pi) for 72 h at 30ºC. The molecular mass was 58 kDa and 56 kDa as determined by exclusion chromatography and SDS-PAGE, respectively. This monomeric enzyme shows an apparent optimum pH ranging from 9.5 to 10.5 and Michaelis kinetics for the hydrolysis of p-nitrophenyl phosphate (the Km and Hill coefficient values were 0.35 mM and 1.01, respectively), alpha-naphthyl phosphate (the Km and Hill coefficient values were 0.44 mM and 0.97, respectively), ß-glycerol phosphate (the Km and Hill coefficient values were 2.46 mM and 1.01, respectively) and L-histidinol phosphate (the Km and Hill coefficient values were 0.47 mM and 0.94, respectively) at pH 8.9. The purified enzyme is activated by Mg2+, Zn2+ and Tris-HCl buffer, and is inhibited by Be2+, histidine and EDTA. Also, 0.3 M Tris-HCl buffer protected the purified enzyme against heat inactivation at 70ºC(half-life of 19.0 min, k = 0.036 min-1) as compared to 0.3 M CHES (half-life of 2.3 min, k = 0.392 min-1) in the same experiment.
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Two attenuated bacillus Calmette-Guérin (BCG) preparations derived from the same Moreau strain, Copenhagen but grown in Sauton medium containing starch and bacto-peptone (onco BCG, O-BCG), or asparagine (intradermal BCG, ID-BCG), exhibited indistinguishable DNA sequences and bacterial morphology. The number of viable bacilli recovered from spleen, liver and lungs was approximately the same in mice inoculated with the vaccines and was similarly reduced (over 90%) in mice previously immunized with either BCG vaccine. The humoral immune response evoked by the vaccines was, however, distinct. Spleen cell proliferation accompanying the growth of bacilli in tissue was significantly higher in mice inoculated with O-BCG. These cells proliferated in vitro upon challenge with the corresponding BCG extract. Previous cell treatment with mAb anti-CD4 T cells abolished this effect. Anti-BCG antibodies, as assayed either in serum by ELISA or by determining the number of antibody-producing spleen cells by the spot-ELISA method, were significantly higher in mice inoculated with ID-BCG. Anti-BCG antibodies were detected in all immunoglobulin classes, but they were more prevalent in IgG with the following distribution among its isotypes: IgG1>(IgG2a = IgG2b)>IgG3. When some well-characterized Mycobacterium tuberculosis antigens were used as substitutes for BCG extracts in ELISA, although antibodies against the 65-kDa and 96-kDa proteins were detected significantly, antibodies against the 71-kDa, 38-kDa proteins and lipoarabinomannan were only barely detected or even absent. These results indicate that BCG bacilli cultured in Sauton-asparagine medium permitted the multiplication of bacilli, tending to induce a stronger humoral immune response as compared with bacilli grown in Sauton-starch/bacto-peptone-enriched medium.
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The 5-HT2B/2C receptor antagonist SB 206553 exerts anxiolytic effects in rat models of anxiety. However, these effects have been reported for standard rat strains, thus raising the issue of SB 206553 effects in rat strains displaying different levels of anxiety. Herein, the effects of SB 206553 in a 5-min elevated plus-maze test of anxiety were compared to those of the reference anxiolytic, diazepam, in two rat strains respectively displaying high (Lewis rats) and low (spontaneously hypertensive rats, SHR) anxiety. Diazepam (0.37, 0.75, or 1.5 mg/kg; 30 min before testing) increased in a dose-dependent manner the behavioral measures in SHR, but not in Lewis rats. On the other hand, SB 206553 (1.25, 2.5, or 5 mg/kg; 30 min before testing) failed to alter the anxiety parameters in both strains, whereas it increased closed arm entries in Lewis rats, suggesting that it elicited hyperactivity in the latter strain. Accordingly, the hypolocomotor effect of the nonselective 5-HT2B/2C receptor agonist m-chlorophenylpiperazine (1.5 mg/kg ip 20 min before a 15-min exposure to an activity cage) was prevented by the 1.25 and 2.5 mg/kg doses of SB 206553 in Lewis rats and SHR, respectively. Compared with SHR, Lewis rats may display a lower response to benzodiazepine-mediated effects and a more efficient control of locomotor activity by 5-HT2B/2C receptors.
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Distributed storage systems are studied. The interest in such system has become relatively wide due to the increasing amount of information needed to be stored in data centers or different kinds of cloud systems. There are many kinds of solutions for storing the information into distributed devices regarding the needs of the system designer. This thesis studies the questions of designing such storage systems and also fundamental limits of such systems. Namely, the subjects of interest of this thesis include heterogeneous distributed storage systems, distributed storage systems with the exact repair property, and locally repairable codes. For distributed storage systems with either functional or exact repair, capacity results are proved. In the case of locally repairable codes, the minimum distance is studied. Constructions for exact-repairing codes between minimum bandwidth regeneration (MBR) and minimum storage regeneration (MSR) points are given. These codes exceed the time-sharing line of the extremal points in many cases. Other properties of exact-regenerating codes are also studied. For the heterogeneous setup, the main result is that the capacity of such systems is always smaller than or equal to the capacity of a homogeneous system with symmetric repair with average node size and average repair bandwidth. A randomized construction for a locally repairable code with good minimum distance is given. It is shown that a random linear code of certain natural type has a good minimum distance with high probability. Other properties of locally repairable codes are also studied.
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Measles virus is a highly contagious agent which causes a major health problem in developing countries. The viral genomic RNA is single-stranded, nonsegmented and of negative polarity. Many live attenuated vaccines for measles virus have been developed using either the prototype Edmonston strain or other locally isolated measles strains. Despite the diverse geographic origins of the vaccine viruses and the different attenuation methods used, there was remarkable sequence similarity of H, F and N genes among all vaccine strains. CAM-70 is a Japanese measles attenuated vaccine strain widely used in Brazilian children and produced by Bio-Manguinhos since 1982. Previous studies have characterized this vaccine biologically and genomically. Nevertheless, only the F, H and N genes have been sequenced. In the present study we have sequenced the remaining P, M and L genes (approximately 1.6, 1.4 and 6.5 kb, respectively) to complete the genomic characterization of CAM-70 and to assess the extent of genetic relationship between CAM-70 and other current vaccines. These genes were amplified using long-range or standard RT-PCR techniques, and the cDNA was cloned and automatically sequenced using the dideoxy chain-termination method. The sequence analysis comparing previously sequenced genotype A strains with the CAM-70 Bio-Manguinhos strain showed a low divergence among them. However, the CAM-70 strains (CAM-70 Bio-Manguinhos and a recently sequenced CAM-70 submaster seed strain) were assigned to a specific group by phylogenetic analysis using the neighbor-joining method. Information about our product at the genomic level is important for monitoring vaccination campaigns and for future studies of measles virus attenuation.
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Purification and characterization of individual antigenic proteins are essential for the understanding of the pathogenic mechanisms of mycobacteria and the immune response against them. In the present study, we used anion-exchange chromatography to fractionate cell extracts and culture supernatant proteins from Mycobacterium bovis to identify T-cell-stimulating antigens. These fractions were incubated with peripheral blood mononuclear cells (PBMC) from M. bovis-infected cattle in lymphoproliferation assays. This procedure does not denature proteins and permits the testing of mixtures of potential antigens that could be later identified. We characterized protein fractions with high stimulation indices from both culture supernatants and cell extracts. Proteins were identified by two-dimensional gel electrophoresis followed by N-terminal sequencing or MALDI-TOF. Culture supernatant fractions containing low molecular weight proteins such as ESAT6 and CFP10 and other proteins (85B, MPB70), and the novel antigens TPX and TRB-B were associated with a high stimulation index. These results reinforce the concept that some low molecular weight proteins such as ESAT6 and CFP10 play an important role in immune responses. Also, Rv3747 and L7/L12 were identified in high stimulation index cell extract fractions. These data show that protein fractions with high lymphoproliferative activity for bovine PBMC can be characterized and antigens which have been already described and new protein antigens can also be identified in these fractions.