543 research outputs found
In the Person of Mankind Attempting to Depict Womanhood
Ben Jonson was by no means a minor character of the early seventeenth century. His writings ranged from plays like Sejanus and Every Man in His Humor to poems like Song: To Celia and To the Memory of My Beloved , The Author , Mr. William Shakespeare , and What He Hath Left Us. He was bold in his attempts. As a result, while many of his works are extremely popular, there are several that proved to be not so successful. Jonson\u27s attempt at speaking as a woman in his In the Person of Womankind (In Defense of their Inconstancy) is one example. Jonson fails in his use of words to embody a woman\u27s feelings
A conceptual design of a propulsion system for an autonomous underwater vehicle
The need for developing propulsion systems to support missions of increased endurance for autonomous underwater vehicles is investigated and a conceptual system is proposed, based on currently available technology and desired system characteristics.
The investigation evaluates and ranks alternative energy sources and proposes the use of a closed Brayton cycle gas turbine power plant using a chemical energy heat source with a metallic fuel. A thruster system using electric propulsion motors and screw propellers is selected. Evaluation factors include reliability, depth independent operation, weight, endurance, quietness and efficiency. Reliability of the proposed system is analyzed and the design modified to meet proposed reliability requirements. A knowledge-based system is developed to manage the operation of the propulsion plant in an autonomous manner. A simulation system is developed using Common Lisp and the operation of the propulsion plant and its knowledge-based management system are evaluated using the simulator
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Love, Life and Photographs: a Look at Creativity and Community in Adult Literacy
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A noção de mundo científico como instrumento de análise epistemológica conforme Thomas S. Kuhn /
Dissertação (Mestrado) - Universidade Federal de Santa Catarina, Centro de Filosofia e Ciências Humanas
Factors affecting the teaching of grade 9 locally developed mathematics
This qualitative study explores the factors affecting the teaching of Grade 9 Locally
Developed mathematics. This analysis focuses on what factors teachers perceived as having an
effect on their teaching, as well as how they value these factors in regards to their ability to
effectively teach this particular level of mathematics. I conducted this study by observing two
regional Locally Developed Compulsory Credit (LDCC) mathematics classrooms on a weekly
basis over the course of two academic semesters within a secondary school context in Ontario. I
conducted regular check-ins with each classroom teacher and formally interviewed the two
teachers at the end of the term.
I analysed these observations and interviews using the framework of axiology to explore
what values teachers assigned to various aspects of teaching LDCC mathematics. My analysis
indicates that these particular teachers valued non-curricular factors, such as a safe classroom
environment and the creation of healthy student relationships, as being equally as important as
curriculum factors, and perhaps even more so. Additionally, teachers expressed a strong need for
additional resources to better teach LDCC students. These resources include: teaching resources,
knowledgeable personnel support, and financial resources to supply students with a more
enriching and supportive classroom experience. My analysis suggests that the values that these
teachers held had notable effects on the teachers’ respective practices, suggesting implications
for Locally Developed mathematics courses being taught by other teachers in other contexts
UWB localization for autonomous indoor position control of VTOL UAVs
As the popularity of quadrotor Vertical Take-Off and Landing (VTOL) Unmanned Aerial Vehicles (UAVs) grows, the need for reliable position estimation and control grows as well. Furthermore, with the size of these quadrotors decreasing and indoor use becoming possible, the need for indoor position estimation methods where Global Position System (GPS) measurements are unavailabe, is a growing topic to which many solutions have been suggested. Herein a method fusing Ultra-Wideband (UWB) range measurements and Inertial Measurement Unit (IMU) measurements is implemented to produce reliable position and velocity estimates.
The position and velocity estimates from this system are then used as inputs to a position controller for the VTOL UAV system. Due to the underactuated nature of the system the position cannot be directly controlled, as such an intermediary control signal is defined. This intermediary control is used to determine the desired orientation and thrust of the UAV, which can then be controlled to achieve the desired position control. As the true orientation of the UAV is not directly measurable an observer using the available IMU measurements is utilized to estimate the orientation of the UAV.
Simulation and implementation results for the position estimation system, as well as the position control system are given
Fauna, idade e ambiente deposicional do geossítio Bacia Sedimentar de Curitiba (GBSC1) : formação Guabirotuba, Bacia de Curitiba
Orientador: Prof. Dr. Rodolfo José AnguloTese (doutorado) - Universidade Federal do Paraná, Setor de Ciências da Terra, Programa de Pós-Graduação em Geologia. Defesa : Curitiba, 10/08/2023Inclui referênciasÁrea de concentração: Geologia ExploratóriaResumo: A Bacia de Curitiba é uma bacia sedimentar continental localizada na porção mais meridional do Sistema de Rifte Continental Cenozoico do Sudeste do Brasil. A Formação Guabirotuba é a unidade mais expressiva desta bacia e o Geossítio Bacia Sedimentar de Curitiba (GBSC1) é o único afloramento fossilífero com fósseis de vertebrados conhecido em toda a bacia. As principais fácies sedimentares correspondem areias com estratificação cruzada. A areia é mal selecionada e apresenta teor variado de cascalho e lama. A associação de fácies sedimentares corresponde a depósitos de canais, barras e planícies de areia com dunas subaquáticas e leitos planos e, provavelmente com ilhas de vegetação em um sistema fluvial entrelaçado. As características sedimentares indicam transporte curto e intemperismo químico baixo ou moderado. A ocorrência de intervalos com cimentação de carbonato de cálcio em algumas fácies sugere que a bacia esteve sob um clima semiárido em pelo menos em algum período. Neste geossítio foi encontrada uma diversificada fauna do Eoceno médio superior, denominada Fauna Guabirotuba que inclui: xenartros (Cingulata), ungulados nativos sulamericanos (Interatheriidae, Oldfieldthomasiidae, Astrapotheria e Pyrotheria), e metatérios (Sparassodonta, Palaeothentoidea e Argyrolagoidea). A presença de Utaetus buccatus (Cingulata) na Fauna Guabirotuba é confirmada e reforça a Idade Barrancano para a Formação Guabirotuba. Os osteodermos semimóveis e a presença de um escudo peitoral foram descritos pela primeira vez. A distribuição geográfica de U. buccatus, anteriormente restrita à Patagônia argentina, foi ampliada para menores latitudes, do que se pensava anteriormente. O material anteriormente atribuído a um m3 de Pyrotheria foi revisado e reinterpretado como um p3, e com outros três molares incompletos permitiram a sua atribuição a cf. Propyrotherium saxeum (Pyrotheriidae). No Brasil, Pyrotheria era conhecido apenas para a Bacia de Taubaté (Oligoceno), mas agora sua ocorrência também foi confirmada para a Formação Guabirotuba. O estudo do espécime atribuído a uma espécie indeterminada de Nemolestes? sp. apresenta características exclusivas, sugerindo que se trata de um novo gênero e nova espécie de Sparassodonta basal para o Eoceno da América do Sul. O significativo aporte do conhecimento sobre a Fauna Guabirotuba ocorrido em pouco mais de uma década de estudos, tem demonstrado sua relevância para esclarecer aspectos relativos à origem e evolução da fauna continental paleógena sul-americanaAbstract: The Curitiba Basin is a continental sedimentary basin located in the southernmost portion of the Cenozoic Continental Rift System in Southern Brazil. The Guabirotuba Formation is the most expressive unit of this basin and the Geosite Basin Sedimentary of Curitiba (GBSC1) is the only vertebrate fossiliferous outcrop known in the entire basin. The main sedimentary facies are (i) stratified sands (St) and (ii) parallel laminated sand (Sh) with incipient stratification. The sand is poorly sorted and has a variable gravel and mud content. The association of sedimentary facies corresponds to channels, bars, and sand flats with underwater dunes and flat beds, and probably with islands of vegetation in an braided river system. Sedimentary features indicate short transport and moderate chemical weathering. Calcium carbonate cementation in some facies suggests that the basin was under a semi-arid climate. In this geosite, a diversified fauna of the upper middle Eocene was found, called Fauna Guabirotuba, which includes: xenarthrans (Cingulata), south american native ungulates (Interatheriidae, Oldfieldthomasiidae, Astrapotheria and Pyrotheria), and metatherians (Sparassodonta, Palaeothentoidea, and Argyrolagoidea). Utaetus buccatus (Cingulata) in the Guabirotuba Fauna is confirmed and reinforces the Barrancano Age for the Guabirotuba Formation. Semi-movable osteoderms and the presence of a pectoral shield are described for the first time. The geographic distributional range of U. buccatus, previously restricted to Argentine Patagonia, was extended to lower latitudes than previously thought during the Eocene. The material once assigned to a Pyrotheria m3 was revised and reinterpreted as a p3, and with another three incomplete molars allowed its assignment to cf. Propyrotherium saxeum (Pyrotheriidae). In Brazil, Pyrotheria was known only for the Taubaté Basin (Oligocene), but now its occurrence has also been confirmed for the Guabirotuba Formation. The study of the specimen attributed to an undetermined species of Nemolestes? sp. revealed exclusive characteristics, suggesting it is a new genus and species of basal Sparassodonta for the Eocene of South America. The significant contribution of knowledge about the Guabirotuba Fauna occurred in just over a decade of studies; it demonstrated its relevance to clarifying aspects related to the origin and evolution of the South American Paleogene continental faun
Analysis of the effect of hemodialysis on peripheral and central arterial pressure waveforms
Analysis of the effect of hemodialysis on peripheral and central arterial pressure waveforms.BackgroundArterial stiffening is very pronounced in renal patients. Carotid artery stiffening is a powerful predictor of future cardiovascular mortality, and measures of arterial compliance correlate much better with left ventricular mass (LVM) in dialysis patients than does brachial artery blood pressure (BP). The aim of our study was to describe the influence of a hemodialysis (HD) session on arterial cushioning function and to correlate the potential different types of behavior with echocardiographic derived parameters.MethodsRadial artery pressure waveforms were measured and recorded noninvasively by applanation tonometry in 51 healthy patients on regular three times weekly HD. The data were then converted into aortic pressure waveforms using a regression equation (SphymoCor™ apparatus). Measurements were done pre- and post-HD in order to ascertain the effect of a single HD session on arterial hemodynamics. The augmentation index (AGI; the difference between early and late pressure peaks divided by the pulse pressure amplitude) was used as an index for vascular compliance. Reproducibility was assessed in 20 young healthy subjects by determining the aortic pulse wave augmentation index twice from radial artery BP measurements one minute apart. Intraobserver error was 2.4%. For 10 dialysis patients similarly studied, the intraobserver error was 1.6%.ResultsAGI was correlated with subjects' height (r = -0.37, P = 0.009), weight (r = -0.41, P = 0.002), and BP levels: radial systolic BP (r = 0.33, P = 0.018), radial diastolic BP (r = 0.29, P = 0.036), and central systolic BP (r = 0.51, P < 0.001). Comparing the pre- with the post-HD AGI values, four patterns of evolution became apparent: (1) The AGI was negative before the HD session and became even more negative afterward (N = 3 out of 51). (2) The AGI was positive before the HD session but became negative after dialysis (N = 19 out of 51). (3) The AGI was positive before the HD session and, although diminished afterward, remained positive (N = 23 out of 51). (4) The AGI was positive before the HD session and increased afterward (N = 6 out of 51). We also found that in some patients, AGI remained at lower than predialysis levels for at least 24 hours. Significant relationships between echocardiographic parameters and pulse wave contour (PWC) variables included pre-HD AGI and LVM (r = 0.47, P < 0.001). There was better correlation between LVM and derived predialysis aortic systolic BP (r = 0.56, P < 0.001) than measured brachial (peripheral) systolic BP (r = 0.35, P = 0.04). Patients whose waveform remained abnormal (AGI remained positive) after HD had a more dilated LV (LV-EDD = 52.07 ± 3.48 mm) than did those patients for whom HD restored “normal” arterial hemodynamics (LV-EDD 46.86 ± 4.06 mm, P < 0.05).ConclusionsA standard HD session profoundly affected aortic BP waveform characteristics, with a reduction in wave reflection in 88% of patients. However, restoration by HD of a normal aortic waveform was unusual. Patients whose waveform remained abnormal after HD had larger more dilated LV chambers than did those patients for whom HD restored “normal” arterial hemodynamics
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