994 resultados para MB-OFDM
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This master’s thesis is focused on the active magnetic bearings control, specifically the robust control. As carrying out of such kind of control used mixed H2/Hinf controller. So the goal of this work is to design it using Robust Control Toolbox™ in MATLAB and compare it performance and robustness with Hinf robust controller characteristics. But only one degree-of-freedom controller considered.
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Painettu uudelleen: Matthiae Calonii opera omnia I. Holmiae 1829. S. 345-362
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@450 wireless broadband service is Digita’s mobile wireless broadband network service. In @450 network Digita acts as the network operator offering network capacity to service operators. For Digita it is important to know what kind of services its network is capable of and what are the network’s service parameters. The knowledge of the network parameters and the behaviour can be used in advance in the development of new service products. Before a new service product can be offered to service operators a lot of work has to be done. The basic testing is necessary to get an understanding of the basic functionality. The requirement specification has to be done and a new product has to be created. The new product has to be tested. The test results have to be analysed in order to find out if the new product is suitable for real use and with which limitations. The content of this Thesis is the development of wireless technologies, @450 service and network, FLASH-OFDM technology, FLASH-OFDM performance testing and the development of a new service product.
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Dentre os sinais sistêmicos causados pelo envenenamento por veneno de sapo (bufotoxina) em cães, os efeitos cardiotóxicos são um dos mais importantes. O objetivo deste estudo foi avaliar as potenciais alterações no músculo cardíaco de cães envenenados experimentalmente por veneno de sapo e observar as alterações eletrolíticas que podem ocorrer nesse tipo de envenenamento. Utilizaram-se 20 cães divididos em grupo controle (n=5) e grupo envenenado (n=15). O veneno de sapo foi extraído por meio de compressão manual das glândulas paratóides. Após anestesia geral, os cães do grupo controle receberam placebo (solução fisiológica) e os do grupo envenenado uma alíquota do veneno por sonda orogástrica. As colheitas de sangue para dosagem dos marcadores cardíacos foram realizadas seis e 24 horas após o envenenamento. As colheitas de sangue para dosagem dos eletrólitos foram realizadas antes e duas, quatro, seis e 12 horas após o envenenamento. A análise estatística empregada foi o teste não-paramétrico de Mann-Withney (P<0,05). Os cães envenenados por veneno de sapo apresentaram elevação dos níveis dos marcadores cardíacos CK-MB e TnIc, confirmando a cardiotoxicidade do veneno. Hipocalemia e hipocalcemia foram também observadas nos cães envenenados.
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Abstract: Although frequently in humans, hypoxic and ischemic heart diseases are poorly documented in dogs, with only few reports of acute myocardial infarction (AMI) in this species. Some electrocardiographic findings might suggest myocardium hypoxia/ischemia, like ST segment elevation or depression, but there are no studies showing whether deviations in ST segment are associated to myocardial injury and serum increase of creatine phosphokinase (CPK-MB). In order to investigate possible myocardial cells injury in poor perfusion conditions, 38 dogs were studied, 20 with normal electrocardiogram and 18 with ST segment elevation or depression, recorded in lead II, at a paper speed of 50 mm/sec and N sensibility (1mV=1cm). Serum measurement of creatine phosphokinase isoenzyme MB (CPK-MB) in normal dogs (group 1) determined control values (in ng/mL), which were compared to those obtained from dogs with deviation (group 2), which allowed confirmation or not of myocardial injury. CPK-MB mean values obtained from dogs in groups 1 and 2 were 0.540ng/ml (SD±0.890)ng/mL and 0.440ng/mL (SD±1.106), respectively. At a significance level of 5%, the relation of CPK-MB with age, mass and total creatine phosphokinase (CPK-T) was not significant in groups 1 and 2. CPK-MB showed no difference, at 5% level, between groups 1 and 2. In conclusion, it is possible to use the human chemiluminescent immunometric assay kit in canine species and that hypoxia/ischemia revealed by ST segment deviation does not mean significant myocardium injury.
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The creatine kinase-isoenzyme MB (CK-MB) mass assay is one of the laboratory tests used for the diagnosis of myocardial infarction. It is recommended, however, that reference limits should take gender and race into account. In the present study, we analyzed the plasma CK-MB mass and troponin levels of 244 healthy volunteers without a personal history of coronary artery disease and with no chronic diseases, muscular trauma or hypothyroidism, and not taking statins. The tests were performed with commercial kits, CK-MB mass turbo kit and Troponin I turbo kit, using the Immulite 1000 analyzer from Siemens Healthcare Diagnostic. The values were separated according to gender and showed significant differences by the Mann-Whitney test. Mean (± SD) CK-MB mass values were 2.55 ± 1.09 for women (N = 121; age = 41.20 ± 10.13 years) and 3.49 ± 1.41 ng/mL for men (N = 123; age = 38.16 ± 11.12 years). Gender-specific reference values at the 99th percentile level, according to the Medicalc statistical software, were 5.40 ng/mL for women and 7.13 ng/mL for men. The influence of race was not considered because of the high miscegenation of the Brazilian population. The CK-MB values obtained were higher than the 5.10 mg/mL proposed by the manufacturer of the laboratory kit. Therefore, decision limits should be related to population and gender in order to improve the specificity of this diagnostic tool, avoiding misclassification of patients
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Brown sediment with clasts ranging from small to large in size. The clast shape ranges from angular to sub-rounded. Rotation structures are the most commonly seen micro-structure in this sample. Necking structures, comet structures, grain crushing and lineations can also be seen in minor amounts throughout the sample.
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Brown sediment with clasts ranging from small to large. The clast shape ranges from sub-angular to rounded. Rotation structures and necking structures can commonly be seen throughout the sample. Lineations, comet structures, and grain crushing is also present throughout the sample.
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Dark brown sediment with clasts ranging from small to large in size. The clast shape ranges from angular to sub-rounded. Clasts appear fractured, weathered, and are well dispersed. Lineations and rotation structures are commonly seen throughout the sample. A few comet structures and grain stacks can also be seen.
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Dark clay matrix. Generally structure-less with a few small clasts.
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Clay matrix with a variation in colour (light brown and dark brown). Generally structure-less with a few small clasts.
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Dark clay matrix with a few small and large clasts. The clasts range from angular to sub-rounded. Generally structure-less.
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La relation entre l’obésité et le cancer, bien qu’établie par des études épidémiologiques, est peu connue. Pourtant, environ 25 % des cancers pourraient y être attribuables. Parmi les cancers reliés à l’obésité, les cancers du côlon, du sein chez les femmes ménopausées et de la prostate sont les plus fréquents. Des études sur modèles animaux ont suggéré une association positive entre une diète riche en gras et le développement du cancer mammaire et de la prostate. Nous avons étudié les mécanismes moléculaires par lesquels les acides gras influencent le devenir de lignées de cellules cancéreuses du sein et de la prostate. Ces travaux ont montré que les acides gras insaturés, dont l’oléate, induisent la prolifération cellulaire tandis que les acides gras saturés, dont le palmitate, diminuent la prolifération. Un traitement à l’oléate stimule la formation de gouttelettes lipidiques dans le cytoplasme des cellules de cancer du sein MDA-MB-231 et de la prostate DU145 alors qu’un traitement au palmitate entraîne l’apoptose. Le mécanisme d’action de l’oléate sur la prolifération a été étudié de façon plus approfondie. L’utilisation d’inhibiteurs pharmacologiques nous a permis de déterminer que l’effet prolifératif de l’oléate implique la voie PI3K/Akt, la voie ERK1/2 et l’activation d’un ou de plusieurs récepteur(s) couplé(s) aux protéines G (GPCR). L’oléate induit la phosphorylation rapide des protéines Akt et ERK1/2 dans les cellules de cancer du sein MDA-MB-231 et de la prostate DU145. Au cours des dernières années, deux GPCRs ont été identifiés comme étant activables par des acides gras à moyennes et à longues chaînes, GPR40 et GPR120. GPR40 étant exprimé dans plusieurs lignées cellulaires de cancer du sein et de la prostate contrairement à l’expression de GPR120 qui était inexistante dans la plupart des lignées, nous avons étudié l’implication de GPR40 dans l’effet prolifératif de l’oléate. Ces deux récepteurs n’étant pas exprimés dans les cellules épithéliales mammaires humaines en culture primaire, ces cellules ne répondent pas aux effets de l’oléate sur la prolifération et l’activation des voies de signalisation. L’activation des voies Akt et ERK1/2 par l’oléate dans les cellules MDA-MB-231 et DU145 est potentialisée par la surexpression du récepteur GPR40 et inhibée par l’utilisation d’un siRNA dirigé contre ce récepteur. Cependant, la prolifération induite par l’oléate ne semble pas affectée par la présence d’un siRNA dirigé contre GPR40. L’oléate étant un acide gras, il est capable d’entrer librement dans les cellules et une partie de ses effets sur la prolifération pourrait être attribuée à sa métabolisation. Un agoniste de GPR40, le GW9508, est en mesure d’activer GPR40 sans toutefois entrer dans les cellules ni activer le métabolisme de l’oléate. Le GW9508 stimule la phosphorylation des protéines Akt et ERK1/2 dans les cellules du cancer du sein MDA-MB-231 et de la prostate DU145, mais il n’est pas en mesure d’induire la prolifération cellulaire comme le fait l’oléate. Ces résultats nous permettent de mieux comprendre le mécanisme d’action de l’oléate sur les cellules de cancer du sein et de la prostate. L’oléate induit la signalisation de GPR40 qui est impliquée dans l’activation rapide des voies de signalisation Akt et ERK1/2. De son côté, l’effet prolifératif induit par l’oléate s’effectue par un mécanisme GPR40-indépendant, possiblement lié au métabolisme de l’oléate.
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The modern telecommunication industry demands higher capacity networks with high data rate. Orthogonal frequency division multiplexing (OFDM) is a promising technique for high data rate wireless communications at reasonable complexity in wireless channels. OFDM has been adopted for many types of wireless systems like wireless local area networks such as IEEE 802.11a, and digital audio/video broadcasting (DAB/DVB). The proposed research focuses on a concatenated coding scheme that improve the performance of OFDM based wireless communications. It uses a Redundant Residue Number System (RRNS) code as the outer code and a convolutional code as the inner code. The bit error rate (BER) performances of the proposed system under different channel conditions are investigated. These include the effect of additive white Gaussian noise (AWGN), multipath delay spread, peak power clipping and frame start synchronization error. The simulation results show that the proposed RRNS-Convolutional concatenated coding (RCCC) scheme provides significant improvement in the system performance by exploiting the inherent properties of RRNS.
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Coded OFDM is a transmission technique that is used in many practical communication systems. In a coded OFDM system, source data are coded, interleaved and multiplexed for transmission over many frequency sub-channels. In a conventional coded OFDM system, the transmission power of each subcarrier is the same regardless of the channel condition. However, some subcarrier can suffer deep fading with multi-paths and the power allocated to the faded subcarrier is likely to be wasted. In this paper, we compute the FER and BER bounds of a coded OFDM system given as convex functions for a given channel coder, inter-leaver and channel response. The power optimization is shown to be a convex optimization problem that can be solved numerically with great efficiency. With the proposed power optimization scheme, near-optimum power allocation for a given coded OFDM system and channel response to minimize FER or BER under a constant transmission power constraint is obtained