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An attitude estimation algorithm for a floated inertial referenceSifferlen, Stephen G January 1980 (has links)
Thesis (M.S.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 1980. / MICROFICHE COPY AVAILABLE IN ARCHIVES AND ENGINEERING. / Includes bibliographical references. / by Stephen G. Sifferlen. / M.S.
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Cidade flutuante: uma Manaus sobre as águas (1920-1967)Souza, Leno José Barata 14 May 2010 (has links)
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Previous issue date: 2010-05-14 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / This work search expects to understand the city of Manaus enters the years of 1920 and 1967 from a specific subject: " The Floating City of Manaus" that, inside of this period, it was gradual if forming for the vast coast of the city, if becoming, in middle of the decade of fifty, a social and urban phenomenon produced by a proper culture of the place in which the relation with fluvial waters was always a strong characteristic in the life of the inhabitants of a certain region of amazonian hinterlândia.
Talking with old inhabitants of the city of Manaus, over all with the former inhabitants of the floating city , the research looks for to rediscuss the Manaus of the period, just exit of gomífera its belle époque, traditionally clipped times, from a hegemonic memory, as maximum example of civilization and amazonense progress in contraposition to the historical time of this work, officially retaken for the lode of the lethargic and declining economic crisis.
However, this exactly projected period, for example, to the light of the culture of the floating, while territories of the most varied sociabilities, can be surprised a vibrant and intriguing city that, through the most different experiences of housings, works and recreation was daily complained for its inhabitants.
In this direction, the floating city , was without a doubt, the impactante social experience of this city in transformation. Almost unknown experiences for the Brazilian society, exactly the amazonense, little touched by a local official speech and/or rare contemplated by intellectual works, are classic or current they.
Historiográfics gaps and silence that this work, throughout our reflections, tries to minimize e, especially for intermediary of the verbal narratives, look for to construct new histories and to project other times, always having as reference the culture of the floating housings that if it showed alive and present in the current days of the Manaus / Este trabalho busca compreender a cidade de Manaus entre os anos de 1920 e 1967 a partir de um tema específico: "A Cidade Flutuante de Manaus" que, dentro deste período, foi gradativamente se formando pelo vasto litoral da cidade, se tornando, em meados da década de cinqüenta, um fenômeno social e urbano produzido por uma cultura própria do lugar na qual a relação com as águas fluviais foi sempre uma característica marcante na vida dos ribeirinhos da hinterlândia amazônica.
Conversando com antigos moradores da cidade de Manaus, sobretudo com os ex- moradores da cidade flutuante , a pesquisa procura rediscutir a Manaus do período, recém saída de sua belle époque gomífera, tempos tradicionalmente pinçados, a partir de uma memória hegemônica, como exemplo máximo de civilização e progresso amazonense em contraposição ao tempo histórico deste trabalho, oficialmente retomados pelo veio da crise econômica paralisante e decadente.
No entanto, este mesmo período projetado, por exemplo, à luz da cultura dos flutuantes, enquanto territórios das mais variadas sociabilidades, pode-se surpreender uma cidade pulsante e intrigante que, através das mais diferentes experiências de moradias, trabalhos e lazeres era cotidianamente reclamada pelos seus moradores.
Neste sentido, a cidade flutuante , foi sem dúvida, a mais impactante experiência social desta cidade em transformação. Experiências quase desconhecidas pela sociedade brasileira, mesmo a amazonense, pouco tocada por um discurso oficial local e/ou raramente contemplada por trabalhos intelectuais, sejam eles clássicos ou atuais.
Lacunas e silêncios historiográficos que este trabalho, ao longo de nossas reflexões, tenta minimizar e, especialmente por intermédio das narrativas orais, procura construir novas histórias e projetar outros tempos, sempre tendo como referência a cultura das moradias flutuantes que se mostrou viva e presente nos dias atuais de Manaus
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Demand analysis and privacy of floating car dataCamilo, Giancarlo 13 September 2019 (has links)
This thesis investigates two research problems in analyzing floating car data (FCD): automated segmentation and privacy. For the former, we design an automated segmentation method based on the social functions of an area to enhance existing traffic demand analysis. This segmentation is used to create an extension of the traditional origin-destination matrix that can represent origins of traffic demand. The methods are then combined for interactive visualization of traffic demand, using a floating car dataset from a ride-hailing application. For the latter, we investigate the properties in FCD that may lead to privacy leaks. We present an attack on a real-world taxi dataset, showing that FCD, even though anonymized, can potentially leak privacy. / Graduate
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A hardware MP3 decoder with low precision floating point intermediate storage / En hårdvarubaserad MP3-avkodare som använder flyttal med låg precision för mellanlagringEhliar, Andreas, Eilert, Johan January 2003 (has links)
<p>The effects of using limited precision floating point for intermediate storage in an embedded MP3 decoder are investigated in this thesis. The advantages of using limited precision is that the values need shorter word lengths and thus a smaller memory for storage. </p><p>The official reference decoder was modified so that the effects of different word lengths and algorithms could be examined. Finally, a software and hardware prototype was implemented that uses 16-bit wide memory for intermediate storage. The prototype is classified as a limited accuracy MP3 decoder. Only layer III is supported. The decoder could easily be extended to a full precision MP3 decoder if a corresponding increase in memory usage was accepted.</p>
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Evaluation of a Floating Point Acoustic Echo Canceller ImplementationDahlberg, Anders January 2007 (has links)
<p>This master thesis consists of implementation and evaluation of an AEC, Acoustic Echo Canceller, algorithm in a floating-point architecture. The most important question this thesis will try to answer is to determine benefits or drawbacks of using a floating-point architecture, relative a fixed-point architecture, to do AEC. In a telephony system there is two common forms of echo, line echo and acoustic echo. Acoustic echo is introduced by sound emanating from a loudspeaker, e.g. in a handsfree or speakerphone, being picked up by a microphone and then sent back to the source. The problem with this feedback is that the far-end speaker will hear one, or multiple, time-delayed version(s) of her own speech. This time-delayed version of speech is usually perceived as both confusing and annoying unless removed by the use of AEC. In this master thesis the performance of a floating-point version of a normalized least-mean-square AEC algorithm was evaluated in an environment designed and implemented to approximate live telephony calls. An instruction-set simulator and assembler available at the initiation of this master thesis were extended to enable; zero-overhead loops, modular addressing, post-increment of registers and register-write forwarding. With these improvements a bit-true assembly version was implemented capable of real-time AEC requiring 15 million instructions per second. A solution using as few as eight mantissa bits, in an external format used when storing data in memory, was found to have an insignificant effect on the selected AEC implementation’s performance. Due to the relatively low memory requirement of the selected AEC algorithm, the use of a small external format has a minor effect on the required memory size. In total this indicates that the possible reduction of the memory requirement and related energy consumption, does not justify the added complexity and energy consumption of using a floating-point architecture for the selected algorithm. Use of a floating-point format can still be advantageous in speech-related signal processing when the introduced time delay by a subband, or a similar frequency domain, solution is unacceptable. Speech algorithms that have high memory use and small introduced delay requirements are a good candidate for a floating-point digital signal processor architecture.</p>
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Ode to the Temple of Sound, Floating World-Ukiyo and Meditation on Zeami: An Analysis of Three Works by Alan HovhanessPark, Chung Hoon 02 May 2008 (has links)
This essay, through a thorough examination of primary and secondary sources, presents analyses of three orchestral works from Hovhaness' "fourth-period," a period of time spanning approximately ten years, from 1960 to 1970. This essay focuses on three works from this period: Meditation on Zeami, Floating World, and Ode to the Temple of Sound, written in 1963, 1964 and 1965, respectively. This essay gathers information from various primary and secondary sources in order to provide performers who are preparing works from this period with a single source of information, bringing clarity to theoretical and musicological problems. Analyses of this sort are made all the more necessary by the fact that there are currently no extant recordings of any of the works being studied here, and that two of the works, Meditation on Zeami and Floating World, have never been commercially recorded. Without an aural precedent and guide to follow, analyses of these musics will be a welcome resource for the conductor preparing a performance.
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Development and evaluation of sustained-release floating minitablets/Développement et évaluation de mini-comprimés flottants à libération prolongéeGoole, Jonathan 02 July 2008 (has links)
Parmi toutes les voies d’administration, la voie orale a toujours suscité un grand intérêt. Les formes prises par voie orale présentent une grande facilité d’administration pour le patient, tandis que pour les chercheurs, la physiologie du système gastro-intestinal peut être facilement modélisable. Malheureusement, son importante variabilité, liée principalement au temps de vidange gastrique, peut conduire à une mauvaise reproductibilité des effets thérapeutiques et à une diminution de la biodisponibilité. Ce problème est surtout rencontré dans le cas des principes actifs présentant une fenêtre d’absorption étroite au niveau de l’intestin supérieur [Deshpande et col., 1996]. Une solution a été de développer des formes galéniques à libération prolongée caractérisées par un temps de résidence gastrique accru. Ainsi, le principe actif est libéré progressivement en amont de sa fenêtre d’absorption. Dans cette optique, plusieurs systèmes ont été développés : des formes bioadhésives, expansibles, gonflantes ou à hautes densités [Singh et Kim, 2000]. Mais parmi toutes ces formes, ce sont les systèmes flottants qui semblent offrir la protection la plus efficace contre une vidange gastrique précoce [Moës, 1989]. Seth et Tossounian ont ainsi développé une gélule flottante à libération prolongée, basée sur le gonflement d’un dérivé cellulosique. Etant une forme monolithique, sa vidange gastrique était soumise au phénomène de tout ou rien. De plus, cette forme présentait un inconvénient majeur puisqu’elle était sujette à des fractionnements intra-gastriques, diminuant de ce fait la reproductibilité inter- et intra-individuelle [Seth et Tossounian, 1984].
Afin de résoudre ces problèmes de variabilité, des mini-comprimés flottants à libération prolongée ont été développés. Notre but était donc de développer des mini-comprimés capables de flotter dans l’estomac pendant une période de temps prolongée tout en assurant la délivrance progressive du principe actif. Ces mini-comprimés devaient fournir une bonne flottaison et une libération prolongée pour diverses substances actives. Nous avons également essayé d’augmenter au maximum la teneur en principe actif afin de faciliter l’administration de la gélule contenant les mini-comprimés en réduisant le volume nécessaire pour contenir la dose désirée. L’utilisation de la granulation thermoplastique [Hamdani et col., 2002] suivie d’une compression directe a permis d’obtenir un procédé de fabrication simple, rapide et peu coûteux. Les mini-comprimés contenaient au minimum un agent actif, un agent liant et un mélange effervescent. La levodopa a d’abord été sélectionnée comme modèle de principe actif hydrosoluble.
La première forme développée renfermait un agent gélifiant cellulosique capable de retenir le dioxyde de carbone généré tout en assurant la libération prolongée du principe actif. En incorporant 17% (m/m) d’agents effervescents et 25% (m/m) d’agent gélifiant au sein des mini-comprimés matriciels, la libération de la levodopa s’est étendue sur une période de 8 heures. Contrairement à la Prolopa® HBS 125, ils n’ont jamais présenté de problème de fragmentation ou de « désintégration » lors des essais de dissolution. Les mini-comprimés matriciels étaient caractérisés par un faible délai de flottaison (± 1 min.) quel que soit le pH (1.2 ou 3.0), des forces de flottaison élevées et une durée totale de flottaison supérieures à 13 heures. Une évaluation par la technique du poids résultant a montré qu’ils généraient des forces de flottaison supérieures – ex. PRmax = 70mg/100mg - à la spécialité commerciale Prolopa® HBS 125 – ex. PRmax = 45mg/100mg.
Suite aux bons résultats obtenus in vitro, une étude préliminaire in vivo a été effectuée sur des sujets volontaires sains. La riboflavine a été préférée à la levodopa comme modèle hydrosoluble en raison du caractère non invasif des prélèvements. L’hypothèse selon laquelle les mini-comprimés flottants offraient une rétention gastrique supérieure à celle obtenue avec les mini-comprimés non flottants semblait avoir été vérifiée. En effet, la quantité totale de riboflavine excrétée après administration concomitante des mini-comprimés flottants et d’un repas était supérieure à celle excrétée avec une forme flottante prise à jeun, ainsi qu’à celle excrétée lors de l’administration de la forme non flottante prise en même temps que le repas. De plus, quel que soit le régime alimentaire, la vitesse d’excrétion urinaire maximale et le temps nécessaire pour l’atteindre ont toujours été supérieurs après administration de la forme flottante.
Une seconde technologie a ensuite permis de remplacer l’agent gélifiant par un enrobage capable de maintenir le dioxyde de carbone à l’intérieur de la forme tout en assurant la libération prolongée de la levodopa. Le but de cette substitution était de pouvoir augmenter le pourcentage de principe actif contenu dans la forme. Un dérivé acrylique insoluble – Eudragit® RL30D – a été utilisé comme agent filmogène. Un agent plastifiant peu hydrosoluble – ATEC – a permis d’obtenir un film élastique résistant aux tensions engendrées par la génération du dioxyde de carbone. En appliquant une teneur équivalente à 20% (m/m) d’enrobage autour du noyau, la libération de la levodopa n’a pas été retardée et s’est prolongée pendant plus de 20 heures. Ces mini-comprimés enrobés ont flotté en 20 minutes à pH 1.2 et ont conservé leurs propriétés de flottaison pendant plus de 13 heures.
L’incorporation de lactose (10% m/m) au sein de l’enrobage a permis de libérer l’entièreté de la levodopa en 18 heures. De plus, en augmentant la teneur en acide tartrique dans le mélange permettant de générer le dioxyde de carbone (de 3 à 15 % m/m), le délai de flottaison, identique quel que soit le pH (1.2 ou 3.0), a été réduit de 20 à 8 minutes.
L’influence des propriétés physico-chimiques de la levodopa et de la ciprofloxacine sur les profils de dissolution et de flottaison obtenus à partir des mini-comprimés matriciels et enrobés a ensuite été évaluée. En l’absence de ciprofloxacine dans la composition de l’enrobage, un retard de libération d’une heure est apparu. Il n’a pu être supprimé qu’en incorporant 10% (m/m) de principe actif au sein de l’enrobage. Aucun problème de ce type ne s’est présenté avec la levodopa.
Quel que soit le principe actif incorporé, les mini-comprimés matriciels et enrobés ont flotté en moins de 10 minutes et pendant plus de 13 heures. Toutefois, les valeurs maximales de poids résultant obtenues ont été supérieures en présence de ciprofloxacine - 220 mg/100mg - qu’après incorporation de levodopa – 90 mg/100mg.
Une étude pharmacocinétique sur volontaires sains a finalement été réalisée sur les mini-comprimés matriciels et enrobés contenant une association de levodopa et de carbidopa. Le but de cette investigation était de comparer les profils pharmacocinétiques de la levodopa et des inhibiteurs de décarboxylases périphériques obtenus à partir des mini-comprimés avec ceux relevés après administration de la spécialité commerciale Prolopa® HBS 125. Une étude scintigraphique a également été réalisée afin d’évaluer le temps de résidence gastrique des 3 formes flottantes. Cette étude a démontré que les mini-comprimés – matriciels et enrobés – présentaient un temps de rétention gastrique supérieure à 4 heures. Ils ont également fourni des concentrations plasmatiques soutenues en levodopa et carbidopa pendant plus de 12 heures. La courbe plasmatique de la levodopa obtenue à partir des mini-comprimés enrobés était similaire à celle obtenue après administration de la Prolopa® HBS 125. Dans les 2 cas, les concentrations plasmatiques en levodopa ont augmenté rapidement après 3 heures. Ce phénomène est sans doute dû aux phénomènes de désintégration observés in vitro et par scintigraphie. Les mini-comprimés matriciels ont fourni des résultats moins variables en fonction du sexe. Ils n’ont présenté aucune désintégration intra-gastrique, ce qui a évité l’apparition d’effet de pic au niveau des concentrations plasmatiques en levodopa. Comparativement à la carbidopa, les concentrations plasmatiques en bensérazide étaient inférieures et présentaient d’importantes variations en fonction du sexe.
Le développement de ces nouveaux types de mini-comprimés a également requis l’examen de leur stabilité temporelle. Pour ce faire, ils ont été conservés à différentes conditions de température et d’humidité relative (25±2°C / 60±5% HR ; 30±2°C / 65±5% HR ; 40±2°C / 75±5% HR). A 25°C et 30°C, aucune diminution significative des teneurs en levodopa et carbidopa n’a été observée à partir des 2 types de mini-comprimés. De même, le profil de dissolution des 2 principes actifs sont restés similaires à celui relevé au temps zéro. Après 12 mois de stockage, les mini-comprimés matriciels et enrobés flottaient endéans 10 min et pendant plus de 13 heures. A 40°C, le profil de dissolution de la levodopa et de la carbidopa, ainsi que les propriétés de flottaison des mini-comprimés matriciels et enrobés sont restés similaires à ceux relevés juste après production. Par contre, après 6 mois de stockage, les teneurs en PA ont diminué de façon significative (p < 0.05) lorsqu’ils étaient contenus dans les mini-comprimés matriciels./
Oral sustained-drug-delivery formulations show some limitations connected with the gastric emptying time. In particular, a too rapid gastrointestinal (GI) transit can result in incomplete drug release from the device above the absorption zone, leading to diminish effectiveness of the administered dose, especially when the drug presents a narrow absorption window. A prolongation of gastric residence time of a rate-controlled oral dosage form (DF) can overcome these problems. Thus, the design of sustained-release (SR) DF requires in some cases both prolongation of GI transit time of the DF as well as controlled drug release. In this way, SR floating granulates, made by melt granulation and containing at least an active drug, a meltable lipidic binder and gas-generating agents, and compressed into minitablets (MT), were developed and evaluated in vitro. The first floating system developed contained Methocel® K15M as a swellable polymer both to trap the generated carbon dioxide and to sustain the release of the drug. For the second floating system developed, Methocel® K15M was completely replaced by the drug and a coating step was introduced in the manufacturing process in order to provide a coating capable of maintaining the generated carbon dioxide inside the DF for a prolonged period of time. Levodopa was used as a model drug. Precirol® was used as a meltable binder. Tartaric acid, sodium bicarbonate and calcium carbonate were employed as carbon dioxide-generating agents. Methocel® K15M was used as a gel-forming polymer. The insoluble polymer used to make the gas-trapping membrane was Eudragit® RL30D. Acetyl-triethyl citrate was used as plasticizer. Granulates were prepared by melt granulation, in a vertical small laboratory scale high-shear mixer. MT were prepared by direct compression. The coating was realized into a fluidized bed coating apparatus. A resultant-weight apparatus was used to determine the buoyancy capabilities of the floating minitablets (FMT). A Disteck 2100C USP 29 dissolution apparatus Type II was used for the dissolution tests. The best floating properties of the uncoated FMT were obtained with 3 mm minitablets prepared at low compression forces ranging between 50 and 100 N. When the FMT were filled into gelatin capsules, no sticking was observed. By evaluating the dissolution profiles of levodopa at different pH values, it was found that dissolution profiles depend more on the prolonged-release ability of Methocel® K15M than on the pH-dependent solubility of levodopa.
On the other hand, the optimized 3mm coated FMT floated within 10 min and remained buoyant for more than 13 h, regardless of the pH of the test medium. By evaluating the dissolution profiles of levodopa at different pH, it was found that the release of levodopa was sustained for more than 12 h regardless of the pH, even if the coating did not cancel the effect of the pH-dependant solubility of the active drug.
Finally, the robustness of the uncoated and the coated FMT was assessed by testing the drug release variability in function of the stirring conditions during dissolution tests.
Two formulations -uncoated and coated - of new FMT were developed with success. The floating lag time of the FMT was ranged between 1 and 10 min and the FMT remained buoyant for more than 13 hours. Their ability to sustain the drug release for more than 8 hours was also demonstrated. Pharmacoscintigraphic studies were conducted on the FMT and the following in vivo results assess those obtained in vitro.
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Marknadsföring på ett djupare plan : En fallstudie av Aqua Floating i KalmarFalk, Lina, Filipovic, Nina January 2010 (has links)
Floating innebär att man ligger i en tank med tempererat saltvatten som gör att man blir tyngdlös och flyter. Floating kan bland annat minska ner stressymptom. Kundens konsumtionsbeteende styrs i hög grad av varumärken. För att stärka ett varumärke måste relationer skapas med hjälp av värdeskapande aktiviteter. Sinnesmarknadsföring är ett sätt att nå ut till kunderna på ett djupare plan och stärka deras relation till varumärket och varumärkets identitet genom att integrera de fem sinnena i marknadsföringen. Servicelandskapet är en viktig del sinnesmarknadsföring. Syftet med denna kandidatuppsats är att undersöka hur sinnen kan integreras i marknadsföringen för att stärka varumärket Aqua Floating och på sätt skapa värde för kunden. Uppsatsen utförs som ett konsultarbete för Aqua Floating i Kalmar och innefattar ett ledarperspektiv som visar på hur ett företag kan använda sig av sensoriella strategier i praktiken. Fallstudien bygger på ett kvalitativt tillvägagångssätt med en huvudsakligen induktiv ansats där den insamlade empirin utgjort grunden för det fortsatta arbetet. Vi har genomfört djupintervjuer, fokusgrupp och webbanalys samt egna observationer. Eftersom vi genomfört en fallstudie har vi ingen möjlighet att generalisera och våra slutsatserna behandlar därför endast företaget Aqua Floating. Sinnesmarknadsföring kan användas för att nå ut till kunderna på ett djupare plan och för att stärka varumärkets identitet. För att detta ska fungera väl krävs dock att företaget etablerar goda relationer med sina kunder och att kunderna upplever att värde skapats. I kapitel 9 sammanfattas författarnas slutsatser som visar på hur Aqua Floating kan stärka sitt varumärke med hjälp av att implementera sinnesmarknadsföring i sitt servicelandskap.
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Time-domain Simulation of Multibody Floating Systems based on State-space Modeling TechnologyYu, Xiaochuan 2011 August 1900 (has links)
A numerical scheme to simulate time-domain motion responses of multibody floating systems has been successfully proposed. This scheme is integrated into a time-domain simulation tool, with fully coupled hydrodynamic coefficients obtained from the hydrodynamic software - WAMIT which solves the Boundary Value Problem (BVP). The equations of motion are transformed into standard state-space format, using the constant coefficient approximation and the impulse response function method. Thus the Ordinary Differential Equation (ODE) solvers in MATLAB can be directly employed. The time-domain responses of a single spar at sea are initially obtained. The optimal Linear Quadratic Regulator (LQR) controller is further applied to this single spar, by assuming that the Dynamic Positioning (DP) system can provide the optimized thruster forces. Various factors that affect the controlling efficiency, e.g., the time steps ∆τ and ∆t, the weighting factors(Q,R), are further investigated in detail. Next, a two-body floating system is studied. The response amplitude operators (RAOs) of each body are calculated and compared with the single body case. Then the effects of the body-to-body interaction coefficients on the time-domain responses are further investigated. Moreover, the mean drift force is incorporated in the DP system to further mitigate the motion responses of each body. Finally, this tool is extended to a three-body floating system, with the relative motions between them derived.
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Algorithms and architectures for decimal transcendental function computationChen, Dongdong 27 January 2011
Nowadays, there are many commercial demands for decimal floating-point (DFP) arithmetic operations such as financial analysis, tax calculation, currency conversion, Internet based applications, and e-commerce. This trend gives rise to further development on DFP arithmetic units which can perform accurate computations with exact decimal operands. Due to the significance of DFP arithmetic, the IEEE 754-2008 standard for floating-point arithmetic includes it in its specifications. The basic decimal arithmetic unit, such as decimal adder, subtracter, multiplier, divider or square-root unit, as a main part of a decimal microprocessor, is attracting more and more researchers' attentions. Recently, the decimal-encoded formats and DFP arithmetic units have been implemented in IBM's system z900, POWER6, and z10 microprocessors.<p>
Increasing chip densities and transistor count provide more room for designers to add more essential functions on application domains into upcoming microprocessors. Decimal transcendental functions, such as DFP logarithm, antilogarithm, exponential, reciprocal and trigonometric, etc, as useful arithmetic operations in many areas of science and engineering, has been specified as the recommended arithmetic in the IEEE 754-2008 standard. Thus, virtually all the computing systems that are compliant with the IEEE 754-2008 standard could include a DFP mathematical library providing transcendental function computation. Based on the development of basic decimal arithmetic units, more complex DFP transcendental arithmetic will be the next building blocks in microprocessors.<p>
In this dissertation, we researched and developed several new decimal algorithms and architectures for the DFP transcendental function computation. These designs are composed of several different methods: 1) the decimal transcendental function computation based on the table-based first-order polynomial approximation method; 2) DFP logarithmic and antilogarithmic converters based on the decimal digit-recurrence algorithm with selection by rounding; 3) a decimal reciprocal unit using the efficient table look-up based on Newton-Raphson iterations; and 4) a first radix-100 division unit based on the non-restoring algorithm with pre-scaling method. Most decimal algorithms and architectures for the DFP transcendental function computation developed in this dissertation have been the first attempt to analyze and implement the DFP transcendental arithmetic in order to achieve faithful results of DFP operands, specified in IEEE 754-2008.<p>
To help researchers evaluate the hardware performance of DFP transcendental arithmetic units, the proposed architectures based on the different methods are modeled, verified and synthesized using FPGAs or with CMOS standard cells libraries in ASIC. Some of implementation results are compared with those of the binary radix-16 logarithmic and exponential converters; recent developed high performance decimal CORDIC based architecture; and Intel's DFP transcendental function computation software library. The comparison results show that the proposed architectures have significant speed-up in contrast to the above designs in terms of the latency. The algorithms and architectures developed in this dissertation provide a useful starting point for future hardware-oriented DFP transcendental function computation researches.
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