999 resultados para Reading log


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A simple but effective technique to improve the performance of the Max-Log-MAP algorithm is to scale the extrinsic information exchanged between two MAP decoders. A comprehensive analysis of the selection of the scaling factors according to channel conditions and decoding iterations is presented in this paper. Choosing a constant scaling factor for all SNRs and iterations is compared with the best scaling factor selection for changing channel conditions and decoding iterations. It is observed that a constant scaling factor for all channel conditions and decoding iterations is the best solution and provides a 0.2-0.4 dB gain over the standard Max- Log-MAP algorithm. Therefore, a constant scaling factor should be chosen for the best compromise.

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The iterative nature of turbo-decoding algorithms increases their complexity compare to conventional FEC decoding algorithms. Two iterative decoding algorithms, Soft-Output-Viterbi Algorithm (SOVA) and Maximum A posteriori Probability (MAP) Algorithm require complex decoding operations over several iteration cycles. So, for real-time implementation of turbo codes, reducing the decoder complexity while preserving bit-error-rate (BER) performance is an important design consideration. In this chapter, a modification to the Max-Log-MAP algorithm is presented. This modification is to scale the extrinsic information exchange between the constituent decoders. The remainder of this chapter is organized as follows: An overview of the turbo encoding and decoding processes, the MAP algorithm and its simplified versions the Log-MAP and Max-Log-MAP algorithms are presented in section 1. The extrinsic information scaling is introduced, simulation results are presented, and the performance of different methods to choose the best scaling factor is discussed in Section 2. Section 3 discusses trends and applications of turbo coding from the perspective of wireless applications.

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May Sinclair was one of the most widely read and successful English women novelists of the first half of the twentieth century. She had interests and themes in common with many of those now considered to have been at the heart of English modernism. In terms of formal experimentation too her concerns chime with the aesthetic innovations of, for example, pound, Eliot and Woolf. Her early interest in psychoanalysis and support for the suffrage campaign also mark her out as a modern. Despite some work from feminist literary critics and her partial categorisation as modernist, however, her work still lacks a critical framework within which it can be read. Indeed, some of the work done by feminist critics on her has paradoxically re-marginalised her. In this thesis I aim to provide one critical framework through which Sinclair's work can be read. My contention is that the occluding of one aspect of her work and thought- its movement toward intellectual, emotional and aesthetic wholeness - has marred previous critical readings of her. By paying attention to this through a focus on discourses of cure, this thesis reads Sinclair's work with an awareness of its language, cultural context and intertextual relations. Early twentieth-century medical discourse, psychoanalysis, mysticism, the chivalric and the psychical are all used to read the works. At the same time, my aim is to read Sinclair's work without eliding its difficulties. Rather, I aim to read her in a way that acknowledges the difficulties of and fraught moments in her writing as markers of its significance.

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Thesis (Ph.D.)--University of Washington, 2015

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As Tennyson's “little Hamlet ,” Maud (1855) posits a speaker who, like Hamlet, confronts the ignominious fate of dead remains. Maud's speaker contemplates such remains as bone, hair, shell, and he experiences his world as one composed of hard inorganic matter, such things as rocks, gems, flint, stone, coal, and gold. While Maud's imagery of “stones, and hard substances” has been read as signifying the speaker's desire “unnaturally to harden himself into insensibility” (Killham 231, 235), I argue that these substances benefit from being read in the context of Tennyson's wider understanding of geological processes. Along with highlighting these materials, the text's imagery focuses on processes of fossilisation, while Maud's characters appear to be in the grip of an insidious petrification. Despite the preoccupation with geological materials and processes, the poem has received little critical attention in these terms. Dennis R. Dean, for example, whose Tennyson and Geology (1985) is still the most rigorous study of the sources of Tennyson's knowledge of geology, does not detect a geological register in the poem, arguing that by the time Tennyson began to write Maud, he was “relatively at ease with the geological world” (Dean 21). I argue, however, that Maud reveals that Tennyson was anything but “at ease” with geology. While In Memoriam (1851) wrestles with religious doubt that is both initiated, and, to some extent, alleviated by geological theories, it finally affirms the transcendence of spirit over matter. Maud, conversely, gravitates towards the ground, concerning itself with the corporal remains of life and with the agents of change that operate on all matter. Influenced by his reading of geology, and particularly Charles Lyell's provocative writings on the embedding and fossilisation of organic material in strata in his Principles of Geology (1830–33) volume 2, Tennyson's poem probes the taphonomic processes that result in the incorporation of dead remains and even living flesh into the geological system.

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O presente artigo teve origem num texto escrito para o programa do espectáculo Frei Luís de Sousa, com encenação de Carlos Avilez, no Teatro Nacional D. Maria II, na abertura das Comemorações do Bicentenário do nascimento de Almeida Garrett.

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A backside protein-surface imprinting process is presented herein as a novel way to generate specific synthetic antibody materials. The template is covalently bonded to a carboxylated-PVC supporting film previously cast on gold, let to interact with charged monomers and surrounded next by another thick polymer. This polymer is then covalently attached to a transducing element and the backside of this structure (supporting film plus template) is removed as a regular “tape”. The new sensing layer is exposed after the full template removal, showing a high density of re-binding positions, as evidenced by SEM. To ensure that the templates have been efficiently removed, this re-binding layer was cleaned further with a proteolytic enzyme and solution washout. The final material was named MAPS, as in the back-side reading of SPAM, because it acts as a back-side imprinting of this recent approach. It was able to generate, for the first time, a specific response to a complex biomolecule from a synthetic material. Non-imprinted materials (NIMs) were also produced as blank and were used as a control of the imprinting process. All chemical modifications were followed by electrochemical techniques. This was done on a supporting film and transducing element of both MAPS and NIM. Only the MAPS-based device responded to oxLDL and the sensing layer was insensitive to other serum proteins, such as myoglobin and haemoglobin. Linear behaviour between log(C, μg mL−1) versus charged tranfer resistance (RCT, Ω) was observed by electrochemical impedance spectroscopy (EIS). Calibrations made in Fetal Calf Serum (FCS) were linear from 2.5 to 12.5 μg mL−1 (RCT = 946.12 × log C + 1590.7) with an R-squared of 0.9966. Overall, these were promising results towards the design of materials acting close to the natural antibodies and applied to practical use of clinical interest.

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Sulfamethoxazole (SMX) is among the antibiotics employed in aquaculture for prophylactic and therapeutic reasons. Environmental and food spread may be prevented by controlling its levels in several stages of fish farming. The present work proposes for this purpose new SMX selective electrodes for the potentiometric determination of this sulphonamide in water. The selective membranes were made of polyvinyl chloride (PVC) with tetraphenylporphyrin manganese (III) chloride or cyclodextrin-based acting as ionophores. 2-nitrophenyl octyl ether was employed as plasticizer and tetraoctylammonium, dimethyldioctadecylammonium bromide or potassium tetrakis (4-chlorophenyl) borate was used as anionic or cationic additive. The best analytical performance was reported for ISEs of tetraphenylporphyrin manganese (III) chloride with 50% mol of potassium tetrakis (4-chlorophenyl) borate compared to ionophore. Nersntian behaviour was observed from 4.0 × 10−5 to 1.0 × 10−2 mol/L (10.0 to 2500 µg/mL), and the limit of detection was 1.2 × 10−5 mol/L (3.0 µg/mL). In general, the electrodes displayed steady potentials in the pH range of 6 to 9. Emf equilibrium was reached before 15 s in all concentration levels. The electrodes revealed good discriminating ability in environmental samples. The analytical application to contaminated waters showed recoveries from 96 to 106%.

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This paper examines academic reading difficulties Angolan second year ELT students have at ISCED (Instituto Superior de Ciências da Educação) in Benguela and focuses on a variety of reading strategies and techniques as well as models for reading materials to help improve academic reading skills. Finally, it recommends the use of appropriate reading strategies and techniques, materials, and the adoption of a more student-centred approach in teaching reading to encourage the development of a reading culture for academic purposes.

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Purpose: Emergency room reading performances have been a point of interest in recent studies comparing radiologists to other physician groups. Our objective was to evaluate and compare the reading performances of radiologists and surgeons in an emergency room setting of non-traumatic abdominal CTs. Methods and materials: A total of ten readers representing four groups participated in this study: three senior radiologists and visceral surgeons, respectively, and two junior radiologists and surgeons, respectively. Each observer blindedly evaluated a total of 150 multi-slice acute abdominal CTs. CTs were chosen representing established proportions of acute abdomen pathologies in a Level I trauma centre from 2003 to 2005. Each answer was interpretated as right or wrong regarding pathology location, diagnosis and need for operation. Gold standard was the intraoperative result, and the clinical patient follow-up for non-operated patients. Significance was assumed at a p <.05 level. Results: Senior radiologists had a mean score of 2.38 ± 1.14, junior radiologists a score of 2.34 ± 1.14, whereas senior surgeons scored 2.07 ± 1.30 and junior surgeons 1.62 ± 1.42. No significant difference was found between the two radiologist groups, but results were significantly better for senior surgeons as compared to junior surgeons and better for the two radiologist groups as compared to each of the surgeon groups (all p <.05). Conclusion: Abdominal CT reading in an acute abdomen setting should continue to rely on an evaluation by a radiologist, whether senior or junior. Satisfying reading results can be achieved by senior visceral surgeons, but junior surgeons need more experience for a good reading performance.

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The exposure to dust and polynuclear aromatic hydrocarbons (PAH) of 15 truck drivers from Geneva, Switzerland, was measured. The drivers were divided between "long-distance" drivers and "local" drivers and between smokers and nonsmokers and were compared with a control group of 6 office workers who were also divided into smokers and nonsmokers. Dust was measured on 1 workday both by a direct-reading instrument and by sampling. The local drivers showed higher exposure to dust (0.3 mg/m3) and PAH than the long-distance drivers (0.1 mg/m3), who showed no difference with the control group. This observation may be due to the fact that the local drivers spend more time in more polluted areas, such as streets with heavy traffic and construction sites, than do the long-distance drivers. Smoking does not influence exposure to dust and PAH of professional truck drivers, as measured in this study, probably because the ventilation rate of the truck cabins is relatively high even during cold days (11-15 r/h). The distribution of dust concentrations was shown in some cases to be quite different from the expected log-normal distribution. The contribution of diesel exhaust to these exposures could not be estimated since no specific tracer was used. However, the relatively low level of dust exposure dose not support the hypothesis that present day levels of diesel exhaust particulates play a significant role in the excess occurrence of lung cancer observed in professional truck drivers.