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Systems Engineering of the Global L-Band Observatory for Water Cycle StudiesSmith, James Nathan 12 April 2022 (has links)
The Global L-band Observatory for Water Cycle Studies (GLOWS) is designed as a follow-on to the Soil Moisture Active Passive (SMAP) observatory launched in 2015. While GLOWS is essentially copying many aspects of the SMAP mission, a key change has been made in the antenna technology. SMAP uses a reflector antenna and to reduce mission costs GLOWS uses a metamaterial lens antenna. This type of antenna is less efficient, so it must be proven that GLOWS can achieve the same uncertainty levels in soil moisture measurements as SMAP. In this work, a unified framework for modeling and analyzing GLOWS' ability to meet all mission and measurement requirements is developed. A model for the uncertainty effects of the lens antenna is developed and used to show that so long as the lens efficiency is above a threshold determined by the accuracy of the lens physical temperature knowledge, GLOWS will also be able to achieve all measurement requirements. It is shown that GLOWS is able to copy the design parameters of SMAP and achieve the same mission requirements.
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Elevers reflektioner om subtraktionsstrategier : En intervjustudie med elever i årskurs 4-6 / Students' reflections on subtraction strategies : An interview study with students in grades 4 and 6Mattsson, Ellinore January 2021 (has links)
Under mina verksamhetsförlagda utbildningar har jag uppmärksammat att flera elever endast behärskar en huvudräkningsstrategi och att de därav inte anpassar strategin utefter uppgiftens utformning. Således är syftet med den här studien att bidra med insikt om elevers subtraktionsstrategier vid huvudräkning. Det här syftet avser jag att uppfylla genom att karaktärisera elevernas reflektioner om subtraktionsstrategier i förhållande till olika aspekter inom det teoretiska ramverket six-lens framework. Studien bygger på en kvalitativ metod. Datainsamlingsmetoden har bestått av intervjuer som har inletts med att eleverna har fått lösa en subtraktionsuppgift med hjälp av en huvudräkningsstrategi. Vid intervjuerna har studien inte fokuserat på huruvida eleverna svarar rätt eller fel på uppgiften, inte heller om eleverna väljer rätt eller fel huvudräkningsstrategi. Istället inriktar sig studien på hur eleverna reflekterar och tänker. Studiens resultat visar att en övervägande del av eleverna inte tillämpar en lämplig huvudräkningsstrategi, de värderar inte heller den valda strategins relevans utifrån hur uppgiften är utformad. Det här innebär att de inte uppnår två av de totalt fem förmågorna inom matematikämnet.
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A Vision-Based Distance Estimation System for Flying CoptersLi, Zetong 16 September 2020 (has links)
Currently, as one of the most popular technologies being discussed and experimented, the application of flying copters in different industries is facing an obvious barrier; which is how to avoid obstacles while flying. One of the industries among all is small-sized package delivery business, which is also the master topic of a series of experiments. The most popular designs that have used for the Flying Copter Obstacle Avoidance System such as lidar scanners and infrared rangefinders are significantly accurate. However, with the heavyweight, expensive price and higher power consumption, these systems cannot be put into mass production. To reduce the cost and power consumption of the Obstacle Avoidance System, an innovative vision-based low-cost Obstacle Distance Estimation System for flying copters is demonstrated in this thesis. The Fisheye Lens Camera is used to provide a broader detection range and accurate results.
Compared to other standard vision-based systems, the Fish Lens Camera Distance Estimation System can provide (around 360 degrees) extensive view for obstacle detection. Through the parallax pictures captured by the camera and the trigonometric rules, the system can estimate the distance to the target obstacle with reasonable results.
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The role of adaptor proteins Crk and CrkL in lens developmentCollins, Tamica N. 04 May 2016 (has links)
Indiana University-Purdue University Indianapolis (IUPUI) / Cell shape changes and signaling pathways are essential for the development and function
of the lens. During lens development proliferating epithelial cells will migrate down to the
equator of the lens, differentiate into lens fiber cells, and begin to elongate along the lens
capsule. The Fibroblast Growth Factor (FGF) signaling pathway has been extensively
studied for its role in lens fiber cell differentiation and elongation. However, the main
mediators of FGF stimulated lens fiber cell elongation have not been identified. Adaptor
proteins Crk and CrkL are SH2- and SH3-containing proteins that transduce signals from
upstream tyrosine phosphorylated proteins to downstream effectors, including Ras, Rac1
and Rap1, which are important for cell proliferation, adhesion and migration. Underlying
their diverse function, these two adaptor proteins have been implicated in receptor tyrosine
kinase signaling, focal adhesion assembly, and cell shape. To explore the role of Crk and
CrkL in FGF signaling-dependent lens development and fiber elongation, we employed
Cre/LoxP system to generate a lens specific knockout of Crk/CrkL. This led to extracellular
matrix defects, disorganization of the lens fiber cells, and a defect in lens fiber cell
elongation. Deletion of Crk and CrkL in the lens also mitigated the gain-of-function
phenotype caused by overexpression of FGF3, indicating an epistatic relationship between
Crk/CrkL and FGF signaling during lens fiber cell elongation. Further studies, revealed
that the activity of Crk and CrkL in FGF signaling is controlled by the phosphatase Shp2
and the defect observed in lens fiber cell elongation can be rescued by constitutive
activation of the GTPases Ras and Rac1 in the Crk and CrkL mutant lens. Interestingly,
the deletion of the GTPases Rap1 in the lens showed no obvious phenotype pertaining to lens fiber cell elongation. These findings suggest that Crk and CrkL play an important role
in integrating FGF signaling and mediating lens fiber cell elongation during lens
development.
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A Novel Catadioptric Ray-Pixel Camera Model and its Application to 3D Reconstruction / 反射屈折撮像系の新たなカメラモデルと3次元形状復元への応用Kawahara, Ryo 25 March 2019 (has links)
京都大学 / 0048 / 新制・課程博士 / 博士(情報学) / 甲第21910号 / 情博第693号 / 新制||情||119(附属図書館) / 京都大学大学院情報学研究科知能情報学専攻 / (主査)講師 延原 章平, 教授 西野 恒, 准教授 飯山 将晃 / 学位規則第4条第1項該当 / Doctor of Informatics / Kyoto University / DFAM
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Contact Lens, Academics, and Self-Perception (CLASP) Study: Study Design and Initial ResultsCoates, Zachary Alan 30 July 2019 (has links)
No description available.
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Compliance and Education in Soft Contact Lens WearersWolfe, Jessica Taylor 02 October 2020 (has links)
No description available.
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Optical Fluid-based Photonic And Display DevicesXu, Su 01 January 2012 (has links)
Conventional solid-state photonic devices exhibit an ultra-high optical performance and durability, but minimal adaptability. Recently, optical fluid-based photonic and display devices are emerging. By dynamically manipulating the optical interface formed by liquids, the optical output can be reconfigured or adaptively tuned in real time. Such devices exhibit some unique characteristics that are not achievable in conventional solid-state photonic devices. Therefore, they open a gateway for new applications, such as image and signal processing, optical communication, sensing, and lab-on-a-chip, etc. Different operation principles of optical fluidbased photonic devices have been proposed, for instance fluidic pressure, electrochemistry, thermal effect, environmentally adaptive hydrogel, electro-wetting and dielectrophoresis. In this dissertation, several novel optical fluid-based photonic and display devices are demonstrated. Their working principles are described and electro-optic properties investigated. The first part involves photonic devices based on fluidic pressure. Here, we present a membrane-encapsulated liquid lens actuated by a photo-activated polymer. This approach paves a way to achieve non-mechanical driving and easy integration with other photonic devices. Next, we develop a mechanical-wetting lens for visible and short-wavelength infrared applications. Such a device concept can be extended to longer wavelength if proper liquids are employed. In the second part, we reveal some new photonic and display devices based on dielectrophoretic effects. We conceive a dielectric liquid microlens with well-shaped electrode for fixing the droplet position and lowering the operating voltage. To widen the dynamic range, we demonstrate an approach to enable focus tuning from negative to positive or vice versa in a single dielectric lens without any moving part. The possibility of fabricating microlens arrays iv with different aperture and density using a simple method is also proposed. Furthermore, the fundamental electro-optic characteristics of dielectric liquid droplets are studied from the aspects of operating voltage, frequency and droplet size. In addition to dielectric liquid lenses, we also demonstrate some new optical switches based on dielectrophoretic effect, e.g., optical switch based on voltage-stretchable liquid crystal droplet, variable aperture or position-shifting droplet. These devices work well in the visible and near infrared spectral ranges. We also extend this approach to display and show a polarizer-free and color filter-free display. Simple fabrication, low power consumption, polarization independence, relatively low operating voltage as well as reasonably fast switching time are their key features.
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Structure and Property Relationship of Oriented Polymers by Solid- State Cross-RollingYang, Yankai 16 March 2011 (has links)
No description available.
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Lens and retina regeneration in amphibian modelsVergara, Maria Natalia 30 April 2008 (has links)
No description available.
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