54 research outputs found
On the Capacity of Low-Density Parity-Check Codes
No full textThe first author would like to express his appreciation to
Thomas .I. Richardson and Riidiger Urbanke for their many
helpful comments and suggestions on this paper
Recommended from our members
Hospitality Students' Attitudes and Behavioral Intentions toward Learning and Using Computer Technology
No full textFollowing Ajzen/Fishbein's 1980 Theory of Reasoned Action, influences of hospitality students' external variables (age, gender, university classification, and work experience) on computer attitudes, and relationships between computer attitudes and intentions to learn and use computers were tested. A sample of 412 hospitality students completed two measurements: Loyd/Gressard's 1984 Computer Attitude Scale, and Behavioral Intentions to Learn and Use Computers. Males and females had positive computer attitudes. Graduates had more positive computer attitudes. No interaction effect existed between gender and classification. No relationships existed between age and work experience on computer attitudes. Computer attitudes positively correlated with intentions to learn and use computers. Results supported the Theory of Reasoned Action. External variables partially influence attitudes and attitudes influence intentions
Diffusion in an absorbing porous medium : from microscopic geometry to macroscopic transport
No full textThesis (S.M.)--Massachusetts Institute of Technology, Dept. of Mechanical Engineering, 2007.This electronic version was submitted by the student author. The certified thesis is available in the Institute Archives and Special Collections.Includes bibliographical references (p. 71-73).Two physical models of diffusion in absorbing porous media are proposed on two length scales. One models diffusion in the pore space of a random medium with absorbing interfaces while the other is a reaction diffusion model where particles are absorbed in the bulk. Typical particle traveling distances and a bulk absorption coefficient are described in terms of general geometrical characteristics of a random medium and the analytical relations are found to compare well with numerical experiments. For the case of geometries consisting of randomly placed cubes, absorption in the bulk scales with the solid fraction to the two-thirds power. The statistical distribution of reaction rates in these models is found to be inversely related to the reaction rate. A quasi-static Monte-Carlo model is also investigated. The more complex problem of microbial extracellular enzyme distributions in marine sediment was an inspiration for this work.by David C. Forney, III.S.M
Cardiac biomarker profiles in dogs with naturally occurring precapillary pulmonary hypertension
No full textIntroduction/objectives: This study evaluated circulating amino-terminal pro-B-type natriuretic peptide (NT-proBNP), amino-terminal pro-A-type natriuretic peptide (NT-proANP), and cardiac troponin I (cTnI) concentrations in dogs with precapillary pulmonary hypertension (Pre-PH) and control dogs with respiratory clinical signs but no Pre-PH.
Animals: Twenty-six dogs (17 affected, and 9 controls) were involved in the study.
Materials and methods: This was a sub-study of a large prospective single-center observational study. Dogs underwent blood sample collection, physical examination, and echocardiographic evaluation. Pre-PH was diagnosed when a calculated right ventricular-to-right atrial pressure gradient (RV:RA PG) measuring ≥40 mmHg was identified echocardiographically, barring right ventricular outflow obstruction and/or left-sided cardiac disease.
Results: Two, nine, and six dogs had mild, moderate, and severe Pre-PH, respectively. Plasma concentrations of NT-proBNP, NT-proANP, and cTnI were significantly higher in the affected group than in the control group (P=0.020, P=0.009, P=0.011, respectively). There was a positive correlation between RV:RA PG and NT-proBNP (r = 0.52), NT-proANP (r = 0.54), and cTnI (r = 0.67) concentrations.
Discussion: Pre-PH should be included in the differential diagnosis list of elevated cardiac biomarker concentrations in dogs with respiratory signs.
Study limitations: Strict selection criteria reduced group sizes. There were rare missing data points. The diagnosis of Pre-PH was obtained from Doppler echocardiographic RV:RA PG. The disease process causing Pre-PH was not evaluated histopathologically.
Conclusions: Circulating cardiac biomarker concentrations are increased in dogs with Pre-PH and there is a positive correlation between RV:RA PG and NT-proBNP, NT-proANP, and cTnI concentrations.
Keywords: Amino-terminal pro-A-type natriuretic peptide (NT-proANP); Amino-terminal pro-B-type natriuretic peptide (NT-proBNP); Respiratory disease; Right ventricle; Troponin I
Pragmatism, Neo-Pragmatism, Language and \u27Truth\u27
No full textThis article takes a look at the place and significance of Rorty’s neo-pragmatism. The author makes an effort to parse out how Rorty fits into the history of pragmatism, philosophies of language, science, and history, and in connection to such explicitly related philosophers as Dewey, James, Davidson, and Kuhn. The author covers a great deal of ground, discussing pragmatist topics such as verification, truth, and culture, as well as Rorty-specific conceptions of semantics, ethnocentrism, post-Kuhn paradigms, and a metaphysics that bears resemblance to Kant’s divided realms
A Simple Construction for the Barnes-Wall Lattices
No full textA certain family of orthogonal groups (called "Clifford groups " by G. E. Wall) has arisen in a variety of different contexts in recent years. These groups have a simple definition as the automorphism groups of certain generalized Barnes-Wall lattices. This leads to an especially simple construction for the usual Barnes-Wall lattices. {This is based on the third author's talk at the Forney-Fest, M.I.T., March 2000, which in turn is based on our paper "The Invariants of the Clifford Groups " Designs, Codes, Crypt., 24 (2001), 99-121, to which the reader is referred for further details and proofs.
Peak power reduction algorithms in asymmetric digital subscriber line modems
No full textThesis (M.Eng.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 2000.Includes bibliographical references (leaves 94-96).This electronic version was submitted by the student author. The certified thesis is available in the Institute Archives and Special Collections.This thesis investigates peak-to-average ratio (PAR) reduction techniques for multicarrier modulation systems, such as discrete multitone (DMT) modems and orthogonal frequency-division multiplexed (OFDM) terrestrial broadcast transmitters. Through simulation and test implementation on a state-of-the-art programmable ADSL development platform, this thesis pursues a suitable solution for minimizing PAR given the resources of a programmable platform. This solution is integrated as a prototype implementation into a fully-functional ADSL modem and optimized for maximum PAR reduction performance within modem complexity constraints.by Athanasios Dimitri Dousis.M.Eng
The crazy (female) artist: iconographies of art, mental illness and gender in Ellen Forney's Marbles
No full textDissertação (mestrado) ? Universidade Federal de Santa Catarina, Centro de Comunicação e Expressão, Programa de Pós-Graduação em Inglês, Florianópolis, 2024.Este estudo procura investigar a graphic memoir Marbles: Mania, Depression, Michelangelo + Me: A Graphic Memoir (2012), de Ellen Forney, que chegou ao Brasil em 2014 sob o título de Parafusos: Mania, depressão Michelangelo e eu: Memórias em quadrinhos. Trata-se de uma graphic memoir, ou seja, memórias contadas como história em quadrinhos em que Forney conta sua narrativa de vida, relatando sua trajetória de vida desde quando recebeu o diagnóstico de Transtorno Bipolar. Para representar sua vivência com doença mental, a autora lança mão de metáforas e recursos possibilitados pela linguagem própria das HQs, uma mídia onde palavras e imagens se mesclam para contar uma história. Ademais, Forney traz em sua obra o conceito de ?Crazy Artists?, uma categoria na qual ela se vê inserida uma vez que foi diagnosticada com Transtorno Bipolar e temia que sua criatividade fosse podada pela medicação que tinha a função de controlar a doença. No presente estudo, pretende-se adicionar uma camada extra a esta discussão: A intenção é estudar em consonância com a análise da linguagem gráfica de Marbles, a história por trás de um estereótipo que une artistas femininas, como Georgia O?Keeffe e Sylvia Plath, retratadas em Marbles, e relaciona a arte dessas mulheres às suas doenças mentais. A hipótese proposta é de que a linguagem das HQs possibilita a diversificação da forma como a percepção da figura dessas artistas femininas pode ser representada através de uma nova iconografiaAbstract: This study seeks to investigate the graphic memoir Marbles: Mania, Depression, Michelangelo + Me: A Graphic Memoir (2012), by Ellen Forney. It is a graphic memoir in which Forney recounts her life trajectory since being diagnosed with Bipolar Disorder. To represent her experience with mental illness, the author uses metaphors and resources made possible by the language of comics, a medium where words and images mix to tell a story. Furthermore, Forney brings in her work the concept of ?Crazy Artists,? a category in which she finds herself inserted since she was diagnosed with Bipolar Disorder and feared that her creativity would be curtailed by the medication that had the function of controlling the illness. In the present study, I intend to add an extra layer to this discussion: the intention is to study, in line with the analysis of Marbles? graphic language, the story behind a stereotype that unites female artists, such as Georgia O?Keeffe and Sylvia Plath, who are portrayed in Marbles, and relates the art of these women to their mental illnesses. The proposed hypothesis is that the language of comics makes it possible to diversify the way in which the perception of the figure of these female artists can be represented through a new iconography
THE INFRARED SPECTRA OF AND ISOLATED IN SOLID NEON
No full textAuthor Institution: Optical Technology Division, National Institute of Standards and TechnologyStudies of the infrared absorptions shown by samples codeposited in a large excess of neon at 5 K with a beam of neon atoms excited in a microwave discharge will be presented. Analysis of the data results in the identification of and of . The previously reported infrared spectral assignment for is revised, and information is obtained regarding the structure of
- …
