762 resultados para Protocol controller


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Kandidaatintyössä toteutetaan OBD2 (On-Board Diagnostics 2) -lukija ajoneuvon päästöjenhallintajärjestelmän diagnostiikkatiedoille yleiskäyttöisellä mikro-ohjaimella. Lukija tukee tiedonsiirtoprotokollana SAE J1850 VPW protokollaa. Mikro-ohjaimena on Atmel Corporationin AVR ATMega328. Työn tavoitteena on havainnoida vastaantulevia käytännön ongelmia ja haasteita mikro-ohjaimen käytöllä tiedonsiirtoprotokollan toteutukseen, ja verrata toteutettua järjestelmää kaupallisiin OBD2-lukijoihin. Työn johtopäätöksenä havaitaan mikro-ohjaimen suorituskyvyn rajoitteet ja sen tuomat toiminnan epävarmuustekijät. Työssä myös todetaan, että mikro-ohjain soveltuu tiedonsiirtoprotokollan toteutukseen kun rajoitteet otetaan huomioon. Kaupallisiin lukijoihin verrattuna yleiskäyttöiseen mikro-ohjaimeen perustuva toteutettu järjestelmä on kalliimpi ja toiminnoiltaan suppeampi. Mikro-ohjaimeen perustuva järjestelmä on kuitenkin muokattavissa ja laajennettavissa tarvittaessa, jolloin toteutukseen voidaan saada kaupallisista järjestelmistä mahdollisesti puuttuvia ominaisuuksia, kuten valmistajakohtaisia protokollia ja toimintoja, joita ei ole määritelty OBD2:ssa. Yhtenä esimerkkinä tällaisesta toiminnosta voi mainita ajoneuvoissa yleistyvän sähköisen käsijarrun säätöä ohjaavat komennot jarruhuoltoa varten.

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Permanent bilateral occlusion of the common carotid arteries (2VO) in the rat has been established as a valid experimental model to investigate the effects of chronic cerebral hypoperfusion on cognitive function and neurodegenerative processes. Our aim was to compare the cognitive and morphological outcomes following the standard 2VO procedure, in which there is concomitant artery ligation, with those of a modified protocol, with a 1-week interval between artery occlusions to avoid an abrupt reduction of cerebral blood flow, as assessed by animal performance in the water maze and damage extension to the hippocampus and striatum. Male Wistar rats (N = 47) aged 3 months were subjected to chronic hypoperfusion by permanent bilateral ligation of the common carotid arteries using either the standard or the modified protocol, with the right carotid being the first to be occluded. Three months after the surgical procedure, rat performance in the water maze was assessed to investigate long-term effects on spatial learning and memory and their brains were processed in order to estimate hippocampal volume and striatal area. Both groups of hypoperfused rats showed deficits in reference (F(8,172) = 7.0951, P < 0.00001) and working spatial memory [2nd (F(2,44) = 7.6884, P < 0.001), 3rd (F(2,44) = 21.481, P < 0.00001) and 4th trials (F(2,44) = 28.620, P < 0.0001)]; however, no evidence of tissue atrophy was found in the brain structures studied. Despite similar behavioral and morphological outcomes, the rats submitted to the modified protocol showed a significant increase in survival rate, during the 3 months of the experiment (P < 0.02).

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Due to differences in study populations and protocols, the hemodynamic determinants of post-aerobic exercise hypotension (PAEH) are controversial. This review analyzed the factors that might influence PAEH hemodynamic determinants, through a search on PubMed using the following key words: “postexercise” or “post-exercise” combined with “hypotension”, “blood pressure”, “cardiac output”, and “peripheral vascular resistance”, and “aerobic exercise” combined only with “blood pressure”. Forty-seven studies were selected, and the following characteristics were analyzed: age, gender, training status, body mass index status, blood pressure status, exercise intensity, duration and mode (continuous or interval), time of day, and recovery position. Data analysis showed that 1) most postexercise hypotension cases are due to a reduction in systemic vascular resistance; 2) age, body mass index, and blood pressure status influence postexercise hemodynamics, favoring cardiac output decrease in elderly, overweight, and hypertensive subjects; 3) gender and training status do not have an isolated influence; 4) exercise duration, intensity, and mode also do not affect postexercise hemodynamics; 5) time of day might have an influence, but more data are needed; and 6) recovery in the supine position facilitates systemic vascular resistance decrease. In conclusion, many factors may influence postexercise hypotension hemodynamics, and future studies should directly address these specific influences because different combinations may explain the observed variability in postexercise hemodynamic studies.

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Lophius gastrophysus has important commercial value in Brazil particularly for foreign trade. In this study, we described the optimization of Random Amplified Polymorphic DNA (RAPD) protocol for identification of L. gastrophysus. Different conditions (annealing temperatures, MgCl concentrations, DNA quantity) were tested to find reproducible and adequate profiles. Amplifications performed with primers A01, ² A02 and A03 generate the best RAPD profiles when the conditions were annealing temperature of 36ºC, 25 ng of DNA quantity and 2.5 mM MgCl2. Exact identification of the species and origin of marine products is necessary and RAPD could be used as an accurate, rapid tool to expose commercial fraud.

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Tässä työssä tutkittiin kahden suomalaisen yrityksen omistamaa yhteisyritystä Venäjällä. Tavoitteena oli kehittää tasapainotettu mittaristo suorituskyvyn mittaukseen johtamisen tueksi. Lisäksi oli tarve parantaa materiaalinhallintaa kehittämällä controllerin työtä helpottava työkalu, sekä kehittää materiaalinhallinnan prosessia läpinäkyvämmäksi ja suoraviivaisemmaksi. Työ koostuu teoreettisesta ja empiirisestä osuudesta. Teoria koostuu raportoinnista, suorituskyvyn mittauksesta ja materiaalinhallinnan seurannasta. Työssä käytettiin laadullisia menetelmiä ja tutkimustyypiksi valikoitui toimintatutkimus. Teoreettinen aineisto on peräisin julkaisuista ja alan kirjallisuudesta. Empiirinen aineisto kerättiin pääosin haastatteluista, benchmarkkauksesta ja dokumenteista. Työn tuloksena saavutettiin päätavoite, eli kehitettiin Excel – pohjaiset työkalut suorituskyvyn mittaukseen ja materiaalinhallinnan seurantaan. Lisäksi kehitettiin kirjallinen ohjeistus näiden työkalujen käyttöön ja materiaalinhallintaprosessien suoraviivaistamiseksi. Diplomityö helpottaa yrityksen johtamista ja kontrollointia sekä sisäisesti että ulkoisesti omistajanäkökulmasta katsottuna. Venäjällä toimivan ulkomaalaisomisteisen yrityksen seuranta on haastavaa, jossa prosessien toimivuus ja läpinäkyvyys ovat olennaisessa roolissa.

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Validation ofan Ice Skating Protocol to Predict Aerobic Power in Hockey Players In assessing the physiological capacity of ice hockey players, researchers have often reported the outcomes from different anaerobic skate tests, and the general physical fitness of participants. However, with respect to measuring the aerobic power of ice hockey players, few studies have reported a sport-specific protocol, and currently there is a lack of cohort-specific information describing aerobic power based on evaluations using an on-ice protocol. The Faught Aerobic Skating Test (FAST) uses an on-ice continuous skating protocol to induce a physical stress on a participant's aerobic energy system. The FAST incorporates the principle of increasing workloads at measured time intervals during a continuous skating exercise. Regression analysis was used to determine the estimate of aerobic power within gender and age level. Data were collected on 532 hockey players, (males=384, females=148) ranging in age between 9 and 25 years. Participants completed a laboratory test to measure aerobic power using a modified Bruce protocol, and the on-ice FAST. Regression equations were developed for six male and female, age-specific cohorts separately. The most consistent predictors were weight and final stage completed on the FAST. These results support the application of the FAST to estimate aerobic power among hockey players with R^ values ranging from 0.174 to 0.396 and SEE ranging from 5.65 to 8.58 ml kg' min'' depending on the cohort. Thus we conclude that FAST to be an accurate predictor of aerobic power in age and gender-specific hockey playing cohorts.

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In 2003, prostate cancer (PCa) is estimated to be the most commonly diagnosed cancer and third leading cause of cancer death in Canada. During PCa population screening, approximately 25% of patients with a normal digital rectal examination (DRE) and intermediate serum prostate specific antigen (PSA) level have PCa. Since all patients typically undergo biopsy, it is expected that approximately 75% of these procedures are unnecessary. The purpose of this study was to compare the degree of efficacy of clinical tests and algorithms in stage II screening for PCa while preventing unnecessary biopsies from occurring. The sample consisted of 201 consecutive men who were suspected of PCa based on the results of a DRE and serum PSA. These men were referred for venipuncture and transrectal ultrasound (TRUS). Clinical tests included TRUS, agespecific reference range PSA (Age-PSA), prostate specific antigen density (PSAD), and free-to-total prostate specific antigen ratio (%fPSA). Clinical results were evaluated individually and within algorithms. Cutoffs of 0.12 and 0.15 ng/ml/cc were employed for PSAD. Cutoffs that would provide a minimum sensitivity of 0.90 and 0.95, respectively were utilized for %fPSA. Statistical analysis included ROC curve analysis, calculated sensitivity (Sens), specificity (Spec), and positive likelihood ratio (LR), with corresponding confidence intervals (Cl). The %fPSA, at a 23% cutoff ({ Sens=0.92; CI, 0.06}, {Spec=0.4l; CI, 0.09}, {LR=1.56; CI, O.ll}), proved to be the most efficacious independent clinical test. The combination of PSAD (cutoff 0.15 ng/ml/cc) and %fPSA (cutoff 23%) ({Sens=0.93; CI, 0.06}, {Spec=0.38; CI, 0.08}, {LR=1.50; CI, 0.10}) was the most efficacious clinical algorithm. This study advocates the use of %fPSA at a cutoff of 23% when screening patients with an intermediate serum PSA and benign DRE.

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The human neuromuscular system is susceptible to changes within the thermal environment. Cold extrinsic temperatures can significantly reduce muscle and nervous system function and communication, which can have consequences for motor performance. A repeated measures design protocol exposed participants to a 12°C cold water immersion (CWI) up to the ankle, knee, and hip to determine the effect that reduced skin and muscle temperature had on balance and strength task execution. Although a linear reduction in the ability to perform balance tasks was seen from the control condition through to the hip CWI, results from the study indicated a significant reduction in dynamic balance (Star Excursion Balance Test reach distance) performance from only the hip CWI (P<0.05). This reduced performance could have been due to an increase in joint stiffness, increased agonist-antagonist co-contraction, and/or reduced isokinetic muscular strength. Reduced physical performance due to cold temperature could negatively impact outdoor recreational athletics.

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L’augmentation du nombre d’usagers de l’Internet a entraîné une croissance exponentielle dans les tables de routage. Cette taille prévoit l’atteinte d’un million de préfixes dans les prochaines années. De même, les routeurs au cœur de l’Internet peuvent facilement atteindre plusieurs centaines de connexions BGP simultanées avec des routeurs voisins. Dans une architecture classique des routeurs, le protocole BGP s’exécute comme une entité unique au sein du routeur. Cette architecture comporte deux inconvénients majeurs : l’extensibilité (scalabilité) et la fiabilité. D’un côté, la scalabilité de BGP est mesurable en termes de nombre de connexions et aussi par la taille maximale de la table de routage que l’interface de contrôle puisse supporter. De l’autre côté, la fiabilité est un sujet critique dans les routeurs au cœur de l’Internet. Si l’instance BGP s’arrête, toutes les connexions seront perdues et le nouvel état de la table de routage sera propagé tout au long de l’Internet dans un délai de convergence non trivial. Malgré la haute fiabilité des routeurs au cœur de l’Internet, leur résilience aux pannes est augmentée considérablement et celle-ci est implantée dans la majorité des cas via une redondance passive qui peut limiter la scalabilité du routeur. Dans cette thèse, on traite les deux inconvénients en proposant une nouvelle approche distribuée de BGP pour augmenter sa scalabilité ainsi que sa fiabilité sans changer la sémantique du protocole. L’architecture distribuée de BGP proposée dans la première contribution est faite pour satisfaire les deux contraintes : scalabilité et fiabilité. Ceci est accompli en exploitant adéquatement le parallélisme et la distribution des modules de BGP sur plusieurs cartes de contrôle. Dans cette contribution, les fonctionnalités de BGP sont divisées selon le paradigme « maître-esclave » et le RIB (Routing Information Base) est dupliqué sur plusieurs cartes de contrôle. Dans la deuxième contribution, on traite la tolérance aux pannes dans l’architecture élaborée dans la première contribution en proposant un mécanisme qui augmente la fiabilité. De plus, nous prouvons analytiquement dans cette contribution qu’en adoptant une telle architecture distribuée, la disponibilité de BGP sera augmentée considérablement versus une architecture monolithique. Dans la troisième contribution, on propose une méthode de partitionnement de la table de routage que nous avons appelé DRTP pour diviser la table de BGP sur plusieurs cartes de contrôle. Cette contribution vise à augmenter la scalabilité de la table de routage et la parallélisation de l’algorithme de recherche (Best Match Prefix) en partitionnant la table de routage sur plusieurs nœuds physiquement distribués.

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A single-feed rectangular-ring microstrip antenna is proposed for indoor communication under the Bluetooth protocol. The dimensions of the antenna together with the location of the feed point are optimized through field simulations in order to cover the Bluetooth bandwidth and to avoid linear polarization. The performance and the efficiency of the antenna are illustrated in a real indoor environment

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Cluster based protocols like LEACH were found best suited for routing in wireless sensor networks. In mobility centric environments some improvements were suggested in the basic scheme. LEACH-Mobile is one such protocol. The basic LEACH protocol is improved in the mobile scenario by ensuring whether a sensor node is able to communicate with its cluster head. Since all the nodes, including cluster head is moving it will be better to elect a node as cluster head which is having less mobility related to its neighbours. In this paper, LEACH-Mobile protocol has been enhanced based on a mobility metric “remoteness” for cluster head election. This ensures high success rate in data transfer between the cluster head and the collector nodes even though nodes are moving. We have simulated and compared our LEACH-Mobile-Enhanced protocol with LEACHMobile. Results show that inclusion of neighbouring node information improves the routing protocol.

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In wireless sensor networks, the routing algorithms currently available assume that the sensor nodes are stationary. Therefore when mobility modulation is applied to the wireless sensor networks, most of the current routing algorithms suffer from performance degradation. The path breaks in mobile wireless networks are due to the movement of mobile nodes, node failure, channel fading and shadowing. It is desirable to deal with dynamic topology changes with optimal effort in terms of resource and channel utilization. As the nodes in wireless sensor medium make use of wireless broadcast to communicate, it is possible to make use of neighboring node information to recover from path failure. Cooperation among the neighboring nodes plays an important role in the context of routing among the mobile nodes. This paper proposes an enhancement to an existing protocol for accommodating node mobility through neighboring node information while keeping the utilization of resources to a minimum.

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Cooperative caching is an attractive solution for reducing bandwidth demands and network latency in mobile ad hoc networks. Deploying caches in mobile nodes can reduce the overall traffic considerably. Cache hits eliminate the need to contact the data source frequently, which avoids additional network overhead. In this paper we propose a data discovery and cache management policy for cooperative caching, which reduces the caching overhead and delay by reducing the number of control messages flooded in to the network. A cache discovery process based on location of neighboring nodes is developed for this. The cache replacement policy we propose aims at increasing the cache hit ratio. The simulation results gives a promising result based on the metrics of studies

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In Wireless Sensor Networks (WSN), neglecting the effects of varying channel quality can lead to an unnecessary wastage of precious battery resources and in turn can result in the rapid depletion of sensor energy and the partitioning of the network. Fairness is a critical issue when accessing a shared wireless channel and fair scheduling must be employed to provide the proper flow of information in a WSN. In this paper, we develop a channel adaptive MAC protocol with a traffic-aware dynamic power management algorithm for efficient packet scheduling and queuing in a sensor network, with time varying characteristics of the wireless channel also taken into consideration. The proposed protocol calculates a combined weight value based on the channel state and link quality. Then transmission is allowed only for those nodes with weights greater than a minimum quality threshold and nodes attempting to access the wireless medium with a low weight will be allowed to transmit only when their weight becomes high. This results in many poor quality nodes being deprived of transmission for a considerable amount of time. To avoid the buffer overflow and to achieve fairness for the poor quality nodes, we design a Load prediction algorithm. We also design a traffic aware dynamic power management scheme to minimize the energy consumption by continuously turning off the radio interface of all the unnecessary nodes that are not included in the routing path. By Simulation results, we show that our proposed protocol achieves a higher throughput and fairness besides reducing the delay