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Optimal design of a flying-wing aircraft inner wing structure configurationHuang, Haidong 01 1900 (has links)
Flying-wing aircraft are considered to have great advantages and potentials in
aerodynamic performance and weight saving. However, they also have many
challenges in design. One of the biggest challenges is the structural design of
the inner wing (fuselage). Unlike the conventional fuselage of a tube
configuration, the flying-wing aircraft inner wing cross section is limited to a
noncircular shape, which is not structurally efficient to resist the internal
pressure load. In order to solve this problem, a number of configurations have
been proposed by other designers such as Multi Bubble Fuselage (MBF),
Vaulted Ribbed Shell (VLRS), Flat Ribbed Shell (FRS), Vaulted Shell
Honeycomb Core (VLHC), Flat Sandwich Shell Honeycomb Core (FLHC), Y
Braced Box Fuselage and the modified fuselage designed with Y brace
replaced by vaulted shell configurations. However all these configurations still
inevitably have structural weight penalty compared with optimal tube fuselage
layout. This current study intends to focus on finding an optimal configuration
with minimum structural weight penalty for a flying-wing concept in a preliminary
design stage.
A new possible inner wing configuration, in terms of aerodynamic shape and
structural layout, was proposed by the author, and it might be referred as
‘Wave-Section Configuration’. The methodologies of how to obtain a structurally
efficient curvature of the shape, as well as how to conduct the initial sizing were
incorporated.
A theoretical analysis of load transmission indicated that the Wave-Section
Configuration is feasible, and this was further proved as being practical by FE
analysis. Moreover, initial FE analysis and comparison of the Wave-Section
Configuration with two other typical configurations, Multi Bubble Fuselage and
Conventional Wing, suggested that the Wave-Section Configuration is an
optimal design in terms of weight saving. However, due to limitations of the
author’s research area, influences on aerodynamic performances have not yet
been taken into account.
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Examining the Complexities of Fostering Social Inclusion in Elementary ClassroomsCleovoulou, Yiola 15 September 2011 (has links)
The purpose of this 1-year case study was to understand how 5 elementary school teachers in an inner-city school foster social inclusion. Through classroom observations and interviews, the study examined the variations of classroom practices the teachers used to create inclusive environments, the challenges they faced in the process, and the strategies they developed to address these challenges. How their work in the classroom interacted with the school's organizational structures was also explored.
Three concepts frame the study: a broad conception of social inclusion that addresses multiple aims for creating an environment of belonging and takes students of all social identities into account; a detailed conception of the practice of social inclusion from a range of theoretical perspectives and teachers' experiences; and a situated conception of context that interrelates the classroom with the school and the community. Three dimensions of pedagogy—content-based practices, relations, and structures—are used to identify and compare principles of inclusive practice. The study portrays the interactions of daily classroom life through cross-case analysis and reveals the complex decision-making processes that teachers use to foster social inclusion.
This study builds on growing scholarship in the field of social inclusion in education (Ainscow et al., 2006; Dei, 1996a; Kosnik & Beck, 2009; Kumashiro, 2002; Topping & Maloney, 2005) and on the increased interest in inclusive pedagogical practices. The in-depth portraits of the teachers’ classroom practices are compared to literature in 4 areas: citizen-based pedagogy, culture-based pedagogy, race-based pedagogy, and anti-oppression pedagogy. The teachers’ practices are analyzed in relation to 2 principles of social inclusion: connecting content to students’ lives and creating mutually supportive social spaces. The study revealed that the participants' practices were mainly associated with pedagogies based on citizenship and culture, with some connections to race-based and anti-oppression pedagogies. What differentiates this study from most other studies in this area is its detailed attention to the dynamic complexity of applying principles of social inclusion to practice. The portraits offer insights into inclusive work in classrooms that will benefit teachers, teacher educators, and researchers interested in expanding the field of social inclusion in education.
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The development of the neurosensory elements of the inner car: the role of sox2and notch signallingMendes Neves, Joana 11 December 2009 (has links)
The experiments described in this thesis report were aimed at studying the functions of Sox2 and Serrate1 during the development of the neurosensory elements of the inner ear. First, we have described the expression pattern of Sox2 during inner ear development and compared to that of Sox3 and Serate1. Secondly, we have shown the results of plasmid based in ovo electroporation experiments, designed to manipulate gene expression exogenously, and to study the gain of function of Sox2 and Serrate1. Effects on cell fate and downstream targets were assessed by in situ hybridization immunohistochemistry and quantitative real-time PCR (qRT-PCR).The results show that Sox2 is expressed in the neurosensory domain of the otic epithelium during the neurogenic period of otic development and, later on, during the development of the prosensory patches and sensory organs. As differentiation proceeds, Sox2 is excluded from differentiated neurones and hair cells, but remains expressed in the supporting cells of the sensory organs. Sox3 is co-expressed with Sox2 in the neurogenic domain of the otic cup. But Sox3 is then down-regulated and only Sox2 expression persists in the sensory precursors, where it is co-expressed with the Notch ligand Serrate1. The expression domain of Serrate1 is initially nested within Sox2, however, later in development Sox2 becomes restricted within the boundaries of Serrate1 expression, a process that is concomitant to the formation of the sensory patches. These expression patterns suggest: 1) that Sox2 correlates with neurosensory fate in the otic placode, 2) that neurogenesis is associated with Sox2 and Sox3 and 3) that sensory development is associated with Sox2 and Serrate1.Gain of function studies show that Serrate1 regulates prosensory fate and sensory organ development by maintaining Sox2 expression in restricted domains of the otocyst, without affecting neurogenesis. Serrate1 operates in a Notch-dependent manner, consistently with a mechanism of lateral induction that includes the induction of its own expression and downstream targets of the Notch signalling pathway Hes1, Hey1 and Hey2. Similar studies on Sox2 indicate that it specifies neurosensory fate in the otic epithelium. However, high concentrations of Sox2 suppress sensory fate and promote neuronal fate. Besides, Sox2 prevents cell differentiation though the cooperation with Notch and BMP signalling pathways.We like to propose a model in which an extended neural competence is early established in the otic placode with the early expression of Sox2 and Sox3 genes. The cooperation between Sox2 and Sox3 then provides a high concentration of SoxB1 protein and promote neuronal fate. In parallel, Serrate1 maintains Sox2 expression in restricted domains, after Sox3 down-regulation. These domains retain the neurosensory competence and thereby develop as sensory patches. / Los experimentos descritos en esta tesis tuvieron por objetivo estudiar la función de Sox2 y Serrate1 en el desarrollo de los elementos neurosensoriales del oído. En primer lugar describimos el patrón de expresión de Sox2 durante el desarrollo del oído y lo comparamos con el de Sox3 y Serrate1. En segundo lugar, mostramos los resultados de experimentos de electroporación in ovo, diseñados para manipular exógenamente la expresión génica y estudiar la ganancia de función de Sox2 y Serrate1. Los efectos sobre el destino celular y las dianas moleculares se analizaron mediante hibridación in situ, inmunocitoquímica y real-time PCR (qRT-PCR).Los resultados muestran que Sox2 se expresa en el dominio neurosensoerial del epitelio ótico durante la fase de neurogénesis y, más adelante, durante el desarrollo de los parches prosensoriales y los órganos sensoriales. Con la diferenciación, Sox2 es excluido de las neuronas diferenciadas y las células ciliadas, pero permanece expresado en las células de soporte. Sox3 se coexpresa con Sox2 en el dominio neurogénico de la copa ótica. Pero entonces, la expresión de Sox3 se reduce y sólo Sox2 persiste en los precursores sensoriales, en donde se co-expresa con el ligando de Notch Serrate1. El dominio de expresión de Serrate1 está inicialmente contenido en el de Sox2, sin embargo, más adelante, Sox2 se restringe dentro de los límites de Serrate1, un proceso que es concomitante con la formación de los parches sensoriales. Estos experimentos sugieren que : 1) Sox2 se correlaciona con el destino neurosensorial de la placoda ótica, 2) la neurogénesis está asociada con Sox2 y Sox3, y 3) el desarrollo sensorial está asociado a la expresión de Sox2 y Serrate1Los estudios de ganancia de función muestran que Serrate1 regula el destino prosensorial y el desarrollo de los órganos sensoriales mediante el mantenimiento de la expresión de Sox2 en dominios restringidos del otocisto, sin afectar a la neurogénesis. Serrate1 opera en un modo dependiente de Notch, consistente con un mecanismo de inducción lateral que comprende la inducción de su propia expresión y la de las dianas de Notch Hes1, Hey1 and Hey2. Estudios similares sobre Sox2 indican que Sox2 especifica el destino neurosensorial en el epitelio ótico. Sin embargo, las concentraciones altas de Sox2 suprimen el destino sensorial y promueven el destino neuronal. Además, Sox2 previene la diferencoiación celular mediante la cooperación con Notch y Bmp. Se propone un modelo en el cual la competencia neural se establece tempranamente en la placoda ótica mediante la expresión temprana de Sox2 y Sox3. La cooperación entre Sox2 y Sox3 provee una alta concentración de factores SoxB1 que promueven el destino neuronal de los progenitores. En paralelo, Serrate1 mantiene la expresión de Sox2 en dominios restringidos tras la supresión de Sox3. Estos dominios, retienen el potencial neurosensorial y, más adelante, se desarrollan como parches sensoriales.
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Barriers to Intensification: A Case Study of Regina's Warehouse DistrictGraham, Rylan R. January 2012 (has links)
This thesis examines the barriers that impede intensification (infill and redevelopment) within Regina’s Warehouse District (The District). In addition this study provides recommendations to overcome said barriers in order to facilitate residential development. This research expands upon two previous studies from 2002 and 2009, which were initiated by community stakeholders and that identified the need for additional residential development within The District. To date, success of the two previous plans in attracting new infill and redevelopment has been limited. This research looks to understand why this is, through the use of semi- structured interviews with key informants. Additional data from secondary documents and visual observations was collected to substantiate this approach. This research found that intensification in The District has been limited due to; unbalanced growth, existing municipal policies and zoning, a negative perception, proximity to noxious uses, an absence of amenities and services, unfavourable land development economics, and a soft demand amongst prospective residents. The second part of this research identified possibilities or factors to facilitate intensification within The District. Similarly these findings are grounded in the discussion with key informants. This data is corroborated by existing planning literature, as well as best practices from a number of North American jurisdictions. This study found that intensification could be facilitated in The District by; balancing growth, revising municipal policy and zoning, increasing public investment, improving the perception, having the city engaged in development, and with increased financial incentives. This research has explored intensification in two unique contexts, a mid-sized Canadian city and a historically industrial neighbourhood. It has contributed to the academic literature by establishing a better understanding of the barriers to intensification within both contexts. More specifically, it has explored intensification within Regina’s Warehouse District, a city that has been largely bypassed by academic planning literature.
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Adaptive Control of Systems in Cascade with SaturationKannan, Suresh Kumar 28 November 2005 (has links)
This thesis extends the use of neural-network-based model reference adaptive control to systems that occur as cascades. In general, these systems are not feedback linearizable. The approach taken is that of approximate feedback linearization of upper subsystems whilst treating the lower-subsystem states as virtual actuators. Similarly, lower-subsystems are also feedback linearized. Typically, approximate inverses are used for linearization purposes. Model error arising from the use of an approximate inverse is minimized using a neural-network as an adaptive element. Incorrect adaptation due to (virtual) actuator saturation and dynamics is avoided using the Pseudocontrol Hedging method. Using linear approximate inverses and linear reference models generally result in large desired pseudocontrol for large external commands. Even if the provided external command is feasible (null-controllable), there is no guarantee that the reference model trajectory is feasible. In order to mitigate this, nonlinear reference models based on nested-saturation methods are used to constrain the evolution of the reference model and thus the plant states. The method presented in this thesis lends itself to the inner-outer loop control of air vehicles, where the inner-loop controls attitude dynamics and the outer-loop controls the translational dynamics of the vehicle. The outer-loop treats the closed loop attitude dynamics as an actuator. Adaptation to uncertainty in the attitude, as well as the translational dynamics, is introduced, thus minimizing the effects of model error in all six degrees of freedom and leading to more accurate position tracking. A pole-placement approach is used to choose compensator gains for the tracking error dynamics. This alleviates timescale separation requirements, allowing the outer loop bandwidth to be closer to that of the inner loop, thus increasing position tracking performance. A poor model of the attitude dynamics and a basic kinematics model is shown to be sufficient for accurate position tracking. In particular, the inner-outer loop method was used to control an unmanned helicopter and has subsequently been applied to a ducted-fan, a fixed-wing aircraft that transitions in and out of hover, and a full-scale rotorcraft. Experimental flight test results are also provided for a subset of these vehicles.
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An Integrated Machine Iron Loss Estimation Scheme based on Steel Magnetizing Characteristics and Emulated Standard Test CircuitLin, Hsiu-Ying 15 August 2012 (has links)
The objective of this thesis is to provide a reliable and effective iron loss estimation scheme for the electromagnetic steel products in the design and on-line operation stages. To investigate the possible performance of electromagnetic steel products, proper iron loss information of the products that are constructed by different steels is one of the key concerns. Along with the various power electronic device applications and iron core structures, the magnetic fluxes flowing through the machine cores will be non-uniform and include harmonic terms. Unless excessive computation efforts in expensive software tools are performed, large discrepancies will be exhibited the estimated and actual values of machine iron losses. To overcome these drawbacks, a rational machine iron loss estimation scheme is proposed. By adopting the iterative magnetic equivalent circuits and the nonlinear magnetic characteristics of the electromagnetic steels, the preliminary operational flux information in the machine is first obtained, and then a numerical Epstein Frame test circuit with magnetizing inductance modeled by Preisach model is applied. With appropriate circuit input voltages devised from preliminary information, the detailed hysteresis inner-loop characteristics resulting from product structures and magnetization harmonics can be properly modeled. Based on the circuit results, the iron losses of electric machines with any operation can be rationally evaluated, and a valuable reference in machine designing can be provided.
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Studies on the morphology of the inner ear and semicircular canal endorgan projections of ha, a medaka behavior mutantIjiri, Kenichi, Yamamoto, Naoyuki, Ishikawa, Yuji, Ito, Hironobu, Noro, Shin-ichi January 2007 (has links)
No description available.
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IC Design and Implementation of Fast Bipolar Inner Product Processor and Analog to Digital ConverterHsueh, Ya-Hsin 20 June 2000 (has links)
This thesis is composed of three independent parts, which are respectively focused on three different applications.
1. A Circuit Design of Fast Bipolar Inner Product Processor for Neural Associative Memory Networks¡G
A novel and high-speed realization of the bipolar-valued inner product processor for associative memory networks is presented. The proposed design is verified to speed up the inner product computation compared with prior works.
2. An Area-Saving 8-bit A/D Converter Using A Binary Search Scheme¡G
A fast and area-saving analog-to-digital converter using DFFs and a digital-to-analog converter is proposed. This design provides a reasonably fast solution for the embedded ADC with the area penalty growing linearly with the data length.
3. A Smart Battery Monitor Emulator System¡G
An efficient smart battery monitor emulator system is designed by using the bq2018 IC of Benchmarq company. This system is aimed to improve the battery monitoring efficiency such that the exact remaining power and time of the battery can be estimated.
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Trafficking of integral membrane proteins of the inner nuclear membrane can be mediated by the ''sorting motif'' of autographa californica nucleopolyhedrovirus odv-e66Williamson, Shawn T 30 October 2006 (has links)
The amino-terminal 33 amino acids of the baculovirus integral membrane
protein, ODV-E66, are sufficient for localization of fusion proteins to viralinduced
intranuclear microvesicles (MV) and occlusion derived virus envelopes
during infection, and has been termed the sorting motif (SM). When abundantly
expressed, SM-fusions are also detected in the inner nuclear membrane (INM),
outer nuclear membrane and endoplasmic reticulum of infected cells, suggesting
proteins with the SM use the same trafficking pathway as cellular INM proteins
to traffic to nuclear membranes. This study identifies the essential
characteristics required for sorting of the SM to the INM of uninfected cells, and
the MV and ODV envelopes of infected cells. These features are an 18 amino
acid transmembrane sequence that lacks polar and charged amino acids (a.a.)
with a cluster of charged a.a. spaced 5-11 residues from the end of the
transmembrane sequence. A comparison of the a.a. sequence of these SM
features with cellular INM proteins shows the features are conserved.
The model of INM protein sorting and localization predicts the only known
sorting event during INM protein trafficking is immobilization/retention in the INM. This study uses confocal microscopy and fluorescence recovery after
photobleaching to compare the localization and mobility of lamin B receptor
(LBR) fusions (which contain SM-like sequences) to a viral SM fusion when
expressed in either mammalian or insect cells. The results show that
immobilization is not necessarily required for accumulation of proteins in the
INM. Furthermore, the results from infected cells show that an active sorting
event, likely independent of immobilization, can distinguish the viral SM from
cellular sequences similar to the SM.
The results of this study show that sorting of proteins to the INM can be
mediated by the viral SM or INM protein SM-like sequences that can function
either independent of, or in addition to, immobilization. These data combined
with recent reports suggest that in addition to diffusion:retention a signal
mediated mechanism for sorting and localization to the INM can occur.
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noneChen, Sian-jhang 24 June 2008 (has links)
Abstract
The purpose of this study was to investigate the drug-using behavioral patterns,
drug abusers¡¦ cognition and inner-containment, the causes of HIV infection, the
relationship between drug abuse and HIV infection, and the acceptable degree of
the government¡¦s harm reduction program.
This study adopted quantitative research design. A total number of 1083 (37.2%
samples had HIV-infected) male drug abusers, whom sampled correctional
institutions, including the drug treatment center, prison and detention house in
Taiwan, were surveyed with self-reported questionnaire. Statistical methods,
including descriptive analysis, Chi-square, t-test, Pearson correlation analysis and
one-way ANOVA, were applied to proof the hypothesis of this study.
The findings were as follows:
I. The proportion of drug-using kin of drug abusers was up to 23.8%. According
to the analysis, the proportion of drug-using siblings was 10.2%, cousins was
4.9%.
II. Non-injecting drug users (NIDUS) had lower tendency in drug craving than
injecting drug users (IDUS), but had higher tendency in inner-containment than
IDUS. Therefore, increasing IDUS¡¦ confidence and coping skills to deal with
craving is important element of relapse prevention program. IDUS had lower
ability of abstinence, so they should be the prior client of harm reduction
program to decrease the harm from drug injection.
III. 52% samples used to needle-sharing would still have needle-sharing
behaviors when facing drug craving. The key factor of sharing behaviors was
they don¡¦t know how to resist the craving and urge of using drugs. Correcting
drug users¡¦ irrational belief could aid in decreasing the craving for drug.
Therefore, drug abusers whom don¡¦t have strong coping response and
concept about the damage of drug abuse should be instructed stress
management abilities and cognitive modification in drug treatment to
effectively prevent relapse.
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