[pt] O objetivo desta dissertação é compreender o trabalho do historiador, segundo Walter Benjamin, como a construção de uma interpretação. Apesar de construída, a interpretação não é arbitrária - ela deve ser capaz de apresentar a verdade histórica. Para tanto, ela é aproximada da contemplação filosófica. O objeto da contemplação é a idéia, que não deve ser entendida como algo restrito ao âmbito do pensamento, mas sim como Ser. A idéia é Ser porque arrasta consigo elementos materiais. Isso não significa, todavia, que ela possa então ser encontrada no mundo empírico. Pelo contrário, os elementos materiais só se apresentam para a faculdade mimética. Ela é capaz de perceber semelhanças entre elementos aparentemente heterogêneos, colocando-os em um estado de tensão. A idéia é a imagem formada por essa configuração, na qual encontramos a verdade histórica. / [en] The objective of this dissertation is to understand the task of the historian, according to Walter Benjamin, as the construction of an interpretation. Although constructed, interpretation is not arbitrary - it must be capable to present historical truth. To accomplish such task, the interpretation should get closer to philosophical contemplation. The object of contemplation is the idea, that should not be understood as something restricted to the scope of thought, but as Being. The idea is Being because it carries material elements inside. This does not mean, however, that it could be found in empirical world. On the contrary, material elements appears only for the mimetic faculty. This faculty is capable to perceive similarities between elements apparently heterogeneous, placing them in a tension state. The idea is the image formed by this configuration, in which it is found historical truth.

DNA similarity studies were used to determine the species of thirty-one strains of bacteria isolated from the hemolymph of infected larvae from Mexico and throughout Central and South America. Twenty-one of the strains were determined to be <I>Paenibacillus popilliae</I> and ten were found to be more closely related to <I>Paenibacillus lentimorbus</I>. Only one of the <I>P. popilliae</I> strains, an isolate from Mexico, was resistant to the antibiotic vancomycin, a trait characteristic of <I>P. popilliae</I> strains from other geographic areas. As expected, all <I>P. lentimorbus</I> strains were sensitive to vancomycin. The polymerase chain reaction (PCR) was used to amplify a portion of a ligase gene necessary for vancomycin resistance in the Mexican strain. Sequencing of the amplicon revealed a sequence identical to that obtained from a North American strain of <I>P. popilliae</I> previously described. The ability of <I>P. popilliae</I> and the inability of <I>P. lentimorbus</I> to grow on medium supplemented with 2% sodium chloride has been used as a phenotypic trait for differentiating between the two species. Approximately 86% of the <I>P. popilliae</I> strains were capable of growth on medium supplemented with 2% sodium chloride and 60% of the <I>P. lentimorbus</I> strains were not capable of growth on this medium. Microscopic examination revealed that all of the Mexican and Central and South American strains of <I>P. popilliae</I> and <I>P. lentimorbus</I> produced a parasporal body. PCR was used to amplify two different regions of the <I>cry18Aa1</I> gene encoding the paraspore in all of the isolates. One primer pair, CryBP2, detected the <I>cry18Aa1</I> gene in 17 of the 21 <I>P. popilliae</I> strains and in all ten of the <I>P. lentimorbus</I> strains. The second primer pair, CryBP4, detected the parasporal gene in 20 of the 21 <I>P. popilliae</I> strains and in all ten of the <I>P. lentimorbus</I> strains. Thirty of the thirty-one <I>P. popilliae</I> and <I>P. lentimorbus</I> strains produced amplicons of approximately 616 bp with the CryBP4 primers. The CryBP4 primers did not detect the paraspore gene in one of the <I>P. popilliae</I> strains. The CryBP2 primer pair produced amplicons of three different sizes, indicating possible variability in the parasporal proteins of <I>P. popilliae</I> and <I>P. lentimorbus</I>. Eleven of the <I>P. popilliae</I> strains produced CryBP2 amplicons approximately 660 bp in size and six of the <I>P. popilliae</I> strains produced CryBP2 amplicons approximately 1100 bp in size. The <I>cry</I> gene was not detected in four of the <I>P. popilliae</I> strains with the CryBP2 primers. The <I>P. lentimorbus</I> strains produced CryBP2 amplicons approximately 750 bp in size. Three PCR products representing the variable CryBP2 amplicon sizes were sequenced and compared to the published <I>cry18Aa1</I> gene sequence. Sequencing data revealed that the Central and South American CryBP2 amplicons are similar to the published <I>cry18Aa1</I> sequence, however, the 1100 bp amplicon has a 453 bp insert that is not found in the published <I>cry18Aa1</I> gene sequence. Paraspores are produced by <I>P. popilliae</I> and <I>P. lentimorbus</I> and is not a reliable phenotypic trait for differentiation between the two species. The ability of Mexican and Central and South American strains of <I>P. lentimorbus</I> to produce paraspores supports the previous findings of a North American group of <I>P. lentimorbus</I> strains that were also capable of producing paraspores. Except for one Mexican strain of <I>P. popilliae</I>, the Central and South American strains of <I>P. popilliae</I> are sensitive to vancomycin. This was unexpected since all North American strains of <I>P. popilliae</I> are vancomycin resistant. Vancomycin resistance could be useful in identifying strains of <I>P. popilliae</I> from North America but not for identifying strains of <I>P. popilliae</I> from Central and South America. So far, no vancomycin resistant strains of <I>P. lentimorbus</I> have been identified. There was variability in the ability of these organisms to grow on medium supplemented with 2% sodium chloride so the usefulness of this trait is debatable. However, the majority of <I>P. popilliae</I> strains from Mexico and Central and South America will grow on medium supplemented with 2% sodium chloride and the majority of the <I>P. lentimorbus</I> strains from these same areas will not grow on this medium. North American strains of <I>P. popilliae</I> and <I>P. lentimorbus</I> also showed variability of growth on medium supplemented with 2% sodium chloride. / Master of Science

The only way to simplify and promote the effective use of an alerting system that must be comprehensive in its coverage of hazardous or non-normal conditions is to convey top level information that provides an indication of criticality and identity. In order to prevent the continued proliferation of aural alerting signals presented in the flight deck, a simple aural alert categorization scheme that provides flight deck function and urgency level information was proposed and evaluated in this study. Specifically, the present investigation examined the ability of a population having "normal" hearing to: 1) distinguish among four sets of aural alerting signals having distinctive rhythmic patterns and pitch contours, 2) perceive three urgency levels having distinctive tempos within each alerting set, and 3) associate each alerting set and its related urgency levels with one of the four major flight deck functions. Magnitude estimation ratings revealed that subjects perceived differences between low urgency level alerts and moderate urgency level alerts and between low urgency level alerts and high urgency level alerts. Pair comparison ratings of similarity revealed that subjects differentiated among the four within of the alerting sets relatively well after participating in a brief training session. alerting sets. A sound identification task revealed that subjects were able to associate functional categories with four aural alerting sets and were also able to simultaneously distinguish among and perceive three urgency levels within each of the alerting sets relatively well after participating in a brief training session. / Master of Science

Episodic memories are neurally coded records of personally experienced events across a lifetime. These records are encoded via medial temporal lobe structures in the brain, including the hippocampus, and are commonly called "representations" or "memory traces". Existing studies indicate that information about the neural signal corresponding to a memory representation can be found in functional magnetic resonance imaging (fMRI) data when the pattern across its smallest units (voxels, often 3mm3 sections of the brain) is measured. Many prior studies have measured these voxel patterns in response to stimuli as if they are a spontaneous brain function, regardless of cognitive factors. These studies sometimes find that similarity in the voxel patterns across repetition of a to-be-remembered event predicts later memory retrieval, but the results are inconsistent. The current fMRI study investigated the possibility that cognitive goals during encoding affect the type of neural representation (voxel pattern) that will later support memory retrieval. This seems likely because prior behavioral studies indicate that cognitive variability across repetitions of an event benefits later memory retrieval, which is difficult to reconcile with the common finding that voxel pattern variability across repetitions of an event harms later memory. We tested this hypothesis by comparing voxel patterns that support later memory retrieval to those associated with forgotten items in the medial temporal lobe, including the hippocampus, and lateral occipital cortex. Overall, as previously demonstrated, the behavioral results showed that exposure to variable cognitive goals across repetition of events during encoding benefited subsequent memory retrieval. Voxel patterns in the hippocampus indicated a significant interaction between cognitive goals (variable vs. consistent) and memory (remembered vs. forgotten) such that less voxel pattern similarity for the repeated events with variable cognitive goals, but not consistent cognitive goals, supported later memory success. In other words, variable hippocampal neural activations for the same events under different cognitive goals predicted better later memory performance. However, there was no significant interaction in neural pattern similarity between cognitive goals and memory success in medial temporal cortices or lateral occipital lobe. Instead, higher similarity in voxel patterns in right medial temporal cortices was associated with later memory retrieval, regardless of cognitive goals. In the lateral occipital lobe, the main effects of cognitive goals, hemisphere, and memory success were found but no interactions. In conclusion, we found that the relationship between pattern similarity and memory success in the hippocampus (but not the medial temporal lobe cortex) changes when the cognitive goal during encoding does or does not vary across repetitions of the event. / Master of Science / Episodic memory is a long-term memory of personal experiences which are encoded via the medial temporal lobe in the brain, primarily in the hippocampus. The records of personal experiences in these areas are commonly called "patterns", "representations", or "memory traces". Prior investigations indicate that the way of measuring the neural signals corresponding to personal events is functional magnetic resonance imaging (fMRI). The brain images taken by an fMRI scanner represent the patterns of the smallest unit (voxels, often 3mm3 sections of the brain). Many prior investigations of episodic memory used the voxel patterns but showed mixed results in whether similarity in the voxel patterns across repetition of a repeated event leads to subsequent memory retrieval. One of the possible explanations for mixed results is that the cognitive factors during encoding were neglected. Therefore, the current fMRI study examined how cognitive goals during encoding influence the voxel patterns that later support memory retrieval. During encoding, participants were shown an image repeated with the same or different questions and answered the question on the screen in an fMRI scanner. After 10 days, they were invited to the item memory test on the images that they were given during the encoding phase. The voxel patterns in the medial temporal lobe, including the hippocampus, and the lateral occipital lobe were compared across the repetitions of each image. The behavioral results showed that variable cognitive goals across repeated events during encoding benefited later memory retrieval. Furthermore, less similar voxel patterns in the hippocampus for the images repeated with different questions, but not the same questions, during encoding predicted better later memory success. In the right medial temporal cortices, higher similarity in voxel patterns was significantly associated with later memory retrieval, regardless of cognitive goals. In the lateral occipital lobe, higher voxel pattern similarity was found in the right hemisphere, for images repeated with the same question, and for images successfully retrieved later. In conclusion, we found that the relationship between voxel pattern similarity and memory success in the hippocampus (but not the medial temporal lobe cortex) changes when the cognitive goal during encoding does or does not vary across repetitions of the event.

Efficiency in algorithms is important, especially in terms of execution time, as it directly impacts user experience. For example, when a customer visits a website, even a mere one-second delay can significantly reduce their patience, and the likelihood of them abandoning the site increases. This principle applies to search algorithms as well. This project is about implementing a time-efficient tree-based search algorithm that focuses on finding similarities between search input and stored data. The objective is to achieve an execution time as close to O(1) regardless of the data size. The implemented algorithm will be compared with a linear search algorithm, which has an execution time that grows along with the data size. By measuring the executiontimes of both search methods, the project aims to demonstrate the superiority of the tree-based search algorithm in terms of time efficiency.

The U.S. Coast Guard maintains a network structure to connect its nation-wide assets. This paper analyzes and models four highly aggregate traces of the traffic to/from the Coast Guard Data Network ship-shore nodes, so that the models may be used to predict future system demand. These internet traces (polled at 5â 40â intervals) are shown to adhere to a Gaussian distribution upon detrending, which imposes limits to the exponential distribution of higher time-resolution traces. Wavelet estimation of the Hurst-parameter is shown to outperform estimation by another common method (Sample-Variances). The First Differences method of detrending proved problematic to this analysis and is shown to decorrelate AR(1) processes where 0.65< phi1 <1.35 and correlate AR(1) processes with phi1 <-0.25. The Hannan-Rissanen method for estimating (phi,theta) is employed to analyze this series and a one-step ahead forecast is generated. / Master of Science

No / Many recent studies have convincingly demonstrated that network traffic exhibits a noticeable self-similar nature which has a considerable impact on queuing performance. However, the networks used in current multicomputers have been primarily designed and analyzed under the assumption of the traditional Poisson arrival process, which is inherently unable to capture traffic self-similarity. Consequently, it is crucial to reexamine the performance properties of multicomputer networks in the context of more realistic traffic models before practical implementations show their potential faults. In an effort toward this end, this paper proposes the first analytical model for wormhole-switched k-ary n-cubes in the presence of self-similar traffic. Simulation experiments demonstrate that the proposed model exhibits a good degree of accuracy for various system sizes and under different operating conditions. The analytical model is then used to investigate the implications of traffic self-similarity on network performance. This study reveals that the network suffers considerable performance degradation when subjected to self-similar traffic, stressing the great need for improving network performance to ensure efficient support for this type of traffic.

Yes / This work presents a methodology to optimize the selection of multiple parameter levels of an image acquisition, degradation, or post-processing process applied to stimuli intended to be used in a subjective image or video quality assessment (QA) study. It is known that processing parameters (e.g. compression bit-rate) or techni- cal quality measures (e.g. peak signal-to-noise ratio, PSNR) are often non-linearly related to human quality judgment, and the model of either relationship may not be known in advance. Using these approaches to select parameter levels may lead to an inaccurate estimate of the relationship between the parameter and subjective quality judgments – the system’s quality model. To overcome this, we propose a method for modeling the rela- tionship between parameter levels and perceived quality distances using a paired comparison parameter selection procedure in which subjects judge the perceived similarity in quality. Our goal is to enable the selection of evenly sampled parameter levels within the considered quality range for use in a subjective QA study. This approach is tested on two applications: (1) selection of compression levels for laparoscopic surgery video QA study, and (2) selection of dose levels for an interventional X-ray QA study. Subjective scores, obtained from the follow-up single stimulus QA experiments conducted with expert subjects who evaluated the selected bit-rates and dose levels, were roughly equidistant in the perceptual quality space - as intended. These results suggest that a similarity judgment task can help select parameter values corresponding to desired subjective quality levels. / Parts of this work were performed within the Telesurgery project (co-funded by iMinds, a digital research institute founded by the Flemish Government; project partners are Unilabs Teleradiology, SDNsquare and Barco, with project support from IWT) and the PANORAMA project (co-funded by grants from Belgium, Italy, France, the Netherlands, the United Kingdom, and the ENIAC Joint Undertaking).

<p>The present study investigates lexical similarity perceptions by students of Swedish as a foreign language (L3) with a good yet non-native proficiency in English (L2). The general theoretical framework is provided by studies in transfer of learning and its specific instance, transfer in language acquisition.</p><p>It is accepted as true that all previous linguistic knowledge is facilitative in developing proficiency in a new language. However, a frequently reported phenomenon is that students see similarities between two systems in a different way than linguists and theoreticians of education do. As a consequence, the full facilitative potential of transfer remains unused.</p><p>The present research seeks to shed light on the similarity perceptions with the focus on the comprehension of a written text. In order to elucidate students’ views, a form involving similarity judgements and multiple choice questions for formally similar items has been designed, drawing on real language use as provided by corpora. 123 forms have been distributed in 6 groups of international students, 4 of them studying Swedish at Level I and 2 studying at Level II. </p><p>The test items in the form vary in the degree of formal, semantic and functional similarity from very close cognates, to similar words belonging to different word classes, to items exhibiting category membership and/or being in subordinate/superordinate relation to each other, to deceptive cognates. The author proposes expected similarity ratings and compares them to the results obtained. The objective measure of formal similarity is provided by a string matching algorithm, Levenshtein distance.</p><p>The similarity judgements point at the fact that intermediate similarity values can be considered problematic. Similarity ratings between somewhat similar items are usually lower than could be expected. Besides, difference in grammatical meaning lowers similarity values significantly even if lexical meaning nearly coincides. Thus, the obtained results indicate that in order to utilize similarities to facilitate language learning, more attention should be paid to underlying similarities.</p>

The present study investigates lexical similarity perceptions by students of Swedish as a foreign language (L3) with a good yet non-native proficiency in English (L2). The general theoretical framework is provided by studies in transfer of learning and its specific instance, transfer in language acquisition. It is accepted as true that all previous linguistic knowledge is facilitative in developing proficiency in a new language. However, a frequently reported phenomenon is that students see similarities between two systems in a different way than linguists and theoreticians of education do. As a consequence, the full facilitative potential of transfer remains unused. The present research seeks to shed light on the similarity perceptions with the focus on the comprehension of a written text. In order to elucidate students’ views, a form involving similarity judgements and multiple choice questions for formally similar items has been designed, drawing on real language use as provided by corpora. 123 forms have been distributed in 6 groups of international students, 4 of them studying Swedish at Level I and 2 studying at Level II.  The test items in the form vary in the degree of formal, semantic and functional similarity from very close cognates, to similar words belonging to different word classes, to items exhibiting category membership and/or being in subordinate/superordinate relation to each other, to deceptive cognates. The author proposes expected similarity ratings and compares them to the results obtained. The objective measure of formal similarity is provided by a string matching algorithm, Levenshtein distance. The similarity judgements point at the fact that intermediate similarity values can be considered problematic. Similarity ratings between somewhat similar items are usually lower than could be expected. Besides, difference in grammatical meaning lowers similarity values significantly even if lexical meaning nearly coincides. Thus, the obtained results indicate that in order to utilize similarities to facilitate language learning, more attention should be paid to underlying similarities.