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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

EXTENSION OF A COMMON DATA FORMAT FOR REAL-TIME APPLICATIONS

Wegener, John A., Davis, Rodney L. 10 1900 (has links)
International Telemetering Conference Proceedings / October 18-21, 2004 / Town & Country Resort, San Diego, California / The HDF5 (Hierarchical Data Format) data storage family is an industry standard format that allows data to be stored in a common format and retrieved by a wide range of common tools. HDF5 is a widely accepted industry standard container for data storage developed by the National Center for Supercomputing Applications (NCSA) at the University of Illinois at Urbana-Champaign. The HDF5 data storage family includes HDF-Time History, intended for data processing, and HDF-Packet, intended for real-time data collection; each of these is an extension to the basic HDF5 format, which defines data structures and associated interrelationships, optimized for that particular purpose. HDF-Time History, developed jointly by Boeing and NCSA, is in the process of being adopted throughout the Boeing test community and by its external partners. The Boeing/NCSA team is currently developing HDF-Packet to support real-time streaming applications, such as airborne data collection and recording of received telemetry. The advantages are significant cost reduction resulting from storing the data in its final format, thus avoiding conversion between a myriad of recording and intermediate formats. In addition, by eliminating intermediate file translations and conversions, data integrity is maintained from recording through processing and archival storage. As well, HDF5 is a general-purpose wrapper, into which can be stored processed data and other data documentation information (such as calibrations), thus making the final data file self-documenting. This paper describes the basics of the HDF-Time History, the extensions required to support real-time acquisition with HDF-Packet, and implementation issues unique to real-time acquisition. It also describes potential future implementations for data acquisition systems in different segments of the test data industry.
2

THE USE OF HDF IN F-22 AVIONICS TEST AND EVALUATION

Barnum, Jil 10 1900 (has links)
International Telemetering Conference Proceedings / October 28-31, 1996 / Town and Country Hotel and Convention Center, San Diego, California / Hierarchical Data Format (HDF) is a public domain standard for file formats which is documented and maintained by the National Center for Super Computing Applications. HDF is the standard adopted by the F-22 program to increase efficiency of avionics data processing and utility of the data. This paper will discuss how the data processing Integrated Product Team (IPT) on the F-22 program plans to use HDF for file format standardization. The history of the IPT choosing HDF, the efficiencies gained by choosing HDF, and the ease of data transfer will be explained.
3

DEVELOPMENT OF NOVEL COPOLYOXETANES: ANTIMICROBIAL AGENTS

King, Allison 01 January 2011 (has links)
This thesis focuses on solution antimicrobial effectiveness for copolyoxetanes with quaternary ammonium and PEG-like side chains. Ring opening copolymerization of 3-((4-bromobutoxy)methyl)-3-methyloxetane (BBOx) and 3-((2-(2-methoxyethoxy) ethoxy) methyl)-3-methyloxetane (ME2Ox) yielded random copolymers with 14-100 (m) mole% BBOx designated P[(BBOx-m)(ME2Ox)]. Reaction of P[(BBOx-m)(ME2Ox)] with dodecyl dimethylamine gave the corresponding quaternary P[(C12-m)(ME2Ox)] polycation salts, designated C12-m. Mole ratios and molecular weights were obtained from 1H-NMR and end group analysis. Differential scanning calorimetry (DSC) studies showed Tg’s between 69 and -34 °C. Minimum inhibitory concentrations (MIC) against Staphylococcus aureus, Escherichia coli and Pseudomonas aeruginosa showed MIC decreasing with increasing C12 mole% reaching a minimum between C12-43 and C12-60. C12-43 had the lowest MIC for all strains. At 5× MIC (challenge:108 cfu/ml), C12 43 kills ≥ 99% of the tested strains within 1 hr. C12-m copolyoxetane cytotoxicity toward human red blood cells, HFF (Human Foreskin Fibroblast) and HDF (Human Dermal Fibroblast) was low, indicating good prospects for biocompatibility. Cx-m copolyoxetane antimicrobial efficacy, hemolytic activity and cytotoxicity were further explored by changing quaternary alkyl chain length. Copolyoxetanes are represented as Cx-50, where 50 is the mole percent quaternary repeat units and ‘x’ is quaternary alkyl chain length (2 to 16 carbons). Reaction of P[(BBOx-m)(ME2Ox)] with a series of tertiary amines yielded the desired quaternary ammonium segment. DSC studies showed Tg’s between -40 °C and -60 °C and melting endotherms for C14-50 and C16-50. A systematic dependence of alkyl chain length on MIC was found with C8-50 being the most effective antimicrobial. Kill kinetics for C8-50 (5× MIC, challenge: 108 cfu/ml) effected >99% kill in 1 hour for S. aureus (7 log reduction). C8-50 efficacy on biomass and cell viability of P. aeruginosa biofilms was investigated. Crystal violet (CV) staining assays demonstrate that C8-50 had no effect on adhesion of already established P. aeruginosa biofilms, but reduced biofilm formation by killing cells prior to attachment. For anti-adhesion assays, noticeable reduction in biofilm mass occurred at concentrations greater than 2× MIC. Viability studies show a substantial log reduction of 2.1 at MIC. The low cytotoxicity of Cx-m copolyoxetanes coupled with low MICs and favorable biofilm results indicate good prospects for therapeutic applications.
4

Photo-biomodulation of human skin fibroblast sub-populations : a systematic approach for the optimization of optical treatment parameters

Mignon, Charles January 2017 (has links)
The thesis presents a rational path for the optimization of the selection of optical treatment parameters in photobiomodulation of human skin fibroblasts. The project begins with an extensive analysis of 90 bibliographic reports in photobiomodulation published between 1985 and 2015, and revealed major inconsistencies in optical parameters selected for clinical applications. Seeking greater clarity for optimal parameter choice, a systematic approach to disentangle the multiple factors underpinning the response of human dermal fibroblasts in vitro to visible and near-infra red (NIR) light was employed. Light-based devices were constructed to specifically and systematically screen the optical parameter window (i.e. wavelength, irradiance and dose) observed in literature. Additionally, critical culture and treatment conditions that have dramatic impact on the outcome of specific light treatment of these human skin dermal cells were identified. In particular, environmental oxygen concentration, cell confluency and serum concentration were all found to have a great effect on the response of dermal fibroblasts to light. In parallel, the induction of reactive oxygen species (ROS) by short visible wavelengths on two dermal fibroblast sub-populations or lineage, reticular and papillary, was monitored by live-cell imaging. The ROS species were found to be created in or close to mitochondria. Lastly, gene expression studies revealed a strong impact of short visible wavelengths, as compared to long and NIR wavelengths on both subpopulations of human dermal fibroblasts. In particular, blue light (450 nm) specifically down-regulated proliferation, metabolism and protein synthesis molecular pathways. At the protein level, 450-nm light inhibited the production of procollagen I in human reticular and papillary fibroblasts in a dose-dependent manner. Gene expression results were in agreement i.e., the same light parameter down-regulated collagen fiber genes, integrins and up-regulated collagenase MMP1. This thesis concludes with a chapter presenting a characterization of the accuracy of a potential translation tool for the prediction of optical photon density inside human skin.
5

Photo-biomodulation of human skin fibroblast sub-populations: a systematic approach for the optimization of optical treatment parameters

Mignon, Charles January 2017 (has links)
The thesis presents a rational path for the optimization of the selection of optical treatment parameters in photobiomodulation of human skin fibroblasts. The project begins with an extensive analysis of 90 bibliographic reports in photobiomodulation published between 1985 and 2015, and revealed major inconsistencies in optical parameters selected for clinical applications. Seeking greater clarity for optimal parameter choice, a systematic approach to disentangle the multiple factors underpinning the response of human dermal fibroblasts in vitro to visible and near-infra red (NIR) light was employed. Light-based devices were constructed to specifically and systematically screen the optical parameter window (i.e. wavelength, irradiance and dose) observed in literature. Additionally, critical culture and treatment conditions that have dramatic impact on the outcome of specific light treatment of these human skin dermal cells were identified. In particular, environmental oxygen concentration, cell confluency and serum concentration were all found to have a great effect on the response of dermal fibroblasts to light. In parallel, the induction of reactive oxygen species (ROS) by short visible wavelengths on two dermal fibroblast sub-populations or lineage, reticular and papillary, was monitored by live-cell imaging. The ROS species were found to be created in or close to mitochondria. Lastly, gene expression studies revealed a strong impact of short visible wavelengths, as compared to long and NIR wavelengths on both subpopulations of human dermal fibroblasts. In particular, blue light (450 nm) specifically down-regulated proliferation, metabolism and protein synthesis molecular pathways. At the protein level, 450-nm light inhibited the production of procollagen I in human reticular and papillary fibroblasts in a dose-dependent manner. Gene expression results were in agreement i.e., the same light parameter down-regulated collagen fiber genes, integrins and up-regulated collagenase MMP1. This thesis concludes with a chapter presenting a characterization of the accuracy of a potential translation tool for the prediction of optical photon density inside human skin. / Marie Skłodowska-Curie Actions.
6

Numerická řešení problematiky EMC malých letadel / Numerical solutions of EMC problems of small airplanes

Šeděnka, Vladimír January 2013 (has links)
Disertace popisuje současné problémy v certifikaci malých letadel, které by se měly v budoucnu řešit numerickým modelováním. Tento postup má zefektivnit návrh a zlevnit certifikaci letadel. Práce je úzce spjata s projektem HIRF-SE, který se problematikou certifikace letadel numerickými metodami zabývá. Podstatná část práce je věnována popisu dvou modulů pro platformu HIRF-SE: řešič BUTFE založený na metodě konečných prvků v časové oblasti a budicí nástroj BUTFE_EXC. Práce popisuje řešení pohlcujících okrajových podmínek, modelování disperzních a anizotropních materiálů a aproximaci tenkých drátů. Speciální pozornost je věnována řešení aproximace tenkých drátů s ostrými ohyby, jejíž současná formulace způsobuje překryvy mezi jednotlivými segmenty drátu.
7

Deep observations of the GOODS-North field from the e-MERGE survey

Wrigley, Nicholas Howard January 2016 (has links)
The Great Observatories Origins Deep Survey North (GOODS-N) field, first surveyed by the HST, has been observed across numerous wavebands revealing populations of both Star Forming Galaxies (SFG) and Active Galactic Nuclei (AGN) over wide ranges of luminosities. It has been surmised that the evolution in the star forming population appears to diverge from that in the AGN population leading to a domination of SFGs at low flux densities. The number of starbursts can only be disentangled from the entire population if each source can be classified individually, which usually requires high angular resolution imaging. This is the motivation behind the e-MERLIN Galaxy Evolution survey, e-MERGE, which expands the depth of high resolution radio imaging in the GOODS-N field to increase the number of potentially classifiable sources. By use of wide-field imaging techniques, including a new high-speed mapping tool, together with a new semi-empirical primary beam-shape model for the e-MERLIN array, a deep wide-field high-resolution map is derived. This is the widest and deepest contiguous imaging yet obtained from e-MERLIN and JVLA observations, and yet contains less than 25% of the e-MERLIN data so far observed. The majority of the objects are shown to exhibit extended structure, and the angular size distribution place the median size around 1.2 arcsec, peaking between 0.5 and 0.7 arcsec. Automated algorithms are utilised to facilitate a new probabilistic classification tool based on multi-parameter correlations. 248 sources could be classified using the tool, each deriving a probability of AGN or SFG rather than forcing a binary category. Linear sizes of star-formation dominated sources are determined to lie in a range of 4 - 11 kpc, within the optical extent of galaxies. Differential source counting based on probabilistic classifications reveals that an increase in the luminosity evolution of SFGs is likely, although an apparent upturn in AGN may also exist to some lesser degree at low flux densities. The thesis establishes a clear roadmap for the remainder of the e-MERGE survey and a path to determine the star formation rate history of the Universe.
8

Evolving strategies to engineer tendon tissue in vitro

Chohan, Sundas January 2016 (has links)
Tendons are able to undergo repeated cyclic loading in vivo without permanent deformation or mechanical failure. However, diseased, traumatised and decellularised tendons gradually lose the ability to resist load and fail because of creep deformation. The molecular basis of the mechanical properties of tendon and how cells establish and maintain these properties is poorly understood. New knowledge in this area is required to develop novel medical strategies to improve tendon repair and regeneration. Recent advances in tissue bioengineering have led to the formation of fibrin-based tendon-like tissue (‘tendon constructs’) that display the mechanical properties and ultrastructure of embryonic tendon. This thesis presents the characterisation of the tendon constructs derived from primary fibroblasts to understand the relationship between the cells and matrix during tissue development, and to establish the standard of in vitro engineered tendons. These findings facilitated protocol development to engineer human tendon-like tissue derived from stem cells. Novel findings of constructs formed from differentiated human pluripotent stem cells in feeder and feeder-free systems are presented. Fibrin gels were seeded with human dermal fibroblasts (HDF), chick tendon fibroblasts (CTF), MAN5 (Manchester, embryonic stem) cells, human embryonic stem cells (HuES7) and induced pluripotent stem cells (iPS). The gels were cultured until isometric tendon-like constructs were formed (T0) or continued for four or ten days post-formation. The mechanical properties, histology and gene expression of the constructs were analysed and compared between the constructs seeded with the aforementioned cell types. Varying the initial cell number (tested in CTF-seeded fibrin and collagen based constructs) significantly affected the final cell count and the mechanical properties of the constructs differentially at T0 and T10. A non-linear relationship exists between the initial and final cell number, and, between the initial cell number and mechanical properties. However, the results showed that cell number impacted cell-matrix stabilisation as strength per se was strongly dependent on initial cell number. Collagen-based constructs showed a significantly lower stiffness compared with fibrin-based constructs at T0 and T10. The stem cells and primary cells reproducibly underwent morphogenesis to form a 3D tissue similar to embryonic tendon in vivo expressing ECM markers such as collagens type I and III. The tissue also exhibited the ultrastructural characteristics and biomechanical profile of immature tendons. RNA seq and qPCR results demonstrated the upregulation of tendon-specific genes. Tendon-like tissue generated from human stem cells and HDFs in vitro has the potential to replace functional tissue lost through disease and to advance the understanding of the molecular basis of human tenogenesis.
9

Manufacture of straw MDF and fibreboards

Halvarsson, Sören January 2010 (has links)
The purpose of this thesis was to develop an economical, sustainable, and environmentally friendly straw Medium Density Fibreboard (MDF) process, capable of full-scale manufacturing and to produce MDF of requested quality. The investigated straw was based on wheat (Triticum aestivum L.) and rice (Oryzae sativa L.). In this thesis three different methods were taken for manufacture of straw MDF; (A) wheat-straw fibre was blowline blended with melamine-modified urea-formaldehyde (MUF), (B) rice-straw fibre was mixed with methylene diphenyl diisocyanate (MDI) in a resin drum-blender, and (C) wheat-straw fibre was activated in the blowline by the addition of Fenton’s reagent (H2O2/Fe2+) for production of non-resin MDF panels.  The MUF/wheat straw MDF panels were approved according to the requirements of the EN standard for MDF (EN 622-5, 2006). The MDI/rice-straw MDF panels were approved according to requirements of the standard for MDF of the American National Standard Institute (ANSI A208.2-2002). The non-resin wheat-straw panels showed mediocre MDF panel properties and were not approved according to the requirements in the MDF standard. The dry process for wood-based MDF was modified for production of straw MDF. The straw MDF process was divided into seven main process steps. 1.       Size-reduction (hammer-milling) and screening of straw 2.       Wetting and heating of straw 3.       Defibration 4.       Resination of straw fibre 5.       Mat forming 6.       Pre-pressing 7.       Hot-pressing       The primary results were that the straw MDF process was capable of providing satisfactory straw MDF panels based on different types of straw species and adhesives. Moreover, the straw MDF process was performed in pilot-plant scale and demonstrated as a suitable method for producing straw MDF from straw bales to finished straw MDF panels. In the environmental perspective the agricultural straw-waste is a suitable source for producing MDF to avoid open field burning and to capture carbon dioxide (CO2), the biological sink for extended time into MDF panels, instead of converting straw directly into bio energy or applying straw fibre a few times as recycled paper. Additionally, the straw MDF panels can be recycled or converted to energy after utilization. A relationship between water retention value (WRV) of resinated straw fibres, the thickness swelling of corresponding straw MDF panels, and the amount of applied adhesive was determined. WRV of the straw fibre increased and the TS of straw MDF declined as a function of the resin content. The empirical models developed were of acceptable significance and the R2 values were 0.69 (WRV) and 0.75 (TS), respectively. Reduced thickness swelling of MDF as the resin content is increased is well-known. The increase of WRV as a function of added polymers is not completely established within the science of fibre swelling. Fortunately, more fundamental research can be initiated and likely a simple method for prediction of thickness swelling of MDF by analysis of the dried and resinated MDF fibres is possible. / Syftet med denna avhandling var att lägga grunden för en ekonomisk, hållbar och miljövänlig MDF process för halmråvara, kapabel för fullskalig produktion av MDF och goda skivegenskaper. Framställningen av MDF skivor utgick från halm av vete (Triticum aestivum L.) och ris (Oryzae sativa L.). Tre olika metoder användes för att producera MDF av halm; (A) fibrer av vetehalm belimmades i blåsledning med ett melaminmodifierat urea-formaldehydlim (MUF), (B) fibrer av rishalm belimmades i en limblandare med metylen difenyl diisocyanate (MDI), (C) Limfria MDF skivor av vetehalm framställdes med aktivering av fibrer genom tillsats av Fenton´s reagens (H2O2/Fe2+) i blåsledning utan någon tillsats av syntetiskt lim. Sammanfattningsvis kan det understrykas att framställda MDF-skivor av MUF/vetehalm var godkända enligt standard för MDF (EN 622-5, 2006). Dessutom var framställda MDF skivor av MDI/rishalm också godkända enligt krav i standard för MDF ”American National Standard Institute” (ANSI A2008.2-2002). Limfria vetehalmskivor visade på måttliga skivegenskaper och klarade inte kraven i MDF standard.   Fiberframställningsprocessen för MDF modifierades till en produktion utgående från halm. MDF processen för halm delades upp i sju primära processoperationer.   (1)            Storleksreducering och sållning av halm (2)            Vätning och uppvärmning av halm (3)            Defibrering (4)            Belimning av halmfiber (5)            Mattformning (6)            Förpressning (7)            Pressning   De viktigaste resultaten från denna studie är att MDF av halm kunde produceras utgående från olika typer av halmsorter och lim. Dessutom utfördes MDF-processen i pilotskala och visade på en lämplig metod för framställning av MDF-skivor från halmbalar till färdiga halmfiberskivor. Det miljömässiga perspektivet på att använda jordbruksavfall till framställning av halmskivor är att undvika förbränning av halm ute på fältet, men det är även möjligt att binda koldioxid (CO2) i halmskivor under längre tid än att omsätta halmråvaran omedelbart som bioenergi eller använda halmfiber som returpapper några få gånger. Dessutom kan MDF återanvändas eller bli omsatt till energi efter användning.   Ett förhållande mellan ”water retention value” (WRV), av belimmade halmfiber, tjocklekssvällning för motsvarande MDF av halmskivor och mängden av tillsatt lim vid olika nivåer har undersökts. Med ökande limhalt tilltog WRV fibersvällning, vidare minskade tjocklekssvällning för motsvarande MDF skivor. De framtagna empiriska modellerna var godtagbara och beräknade R2 värden var 0.69 (WRV) och 0.75 (TS). Minskad tjocklekssvällning med ökad limhalt är dokumenterad sen tidigare. Ökad fibersvällning WRV vid tillsats av polymerer (limmer) är inte fullständigt etablerad inom vetenskapen för fibersvällning. Lyckligtvis kan grundläggande forskning initieras och sannolikt föreligger en enkel metod för att prediktera tjocklekssvällning av MDF genom analyser av torkade och belimmad MDF fiber.
10

Vergleich dielektrisch behinderter Entladungen bezüglich der physikalischen Eigenschaften und der Wirkung auf Holz und Holzwerkstoffe / Comparison of dielectric barrier discharges regarding their physical properties and the influence on wood and wooden materials

Peters, Frauke 22 October 2018 (has links)
No description available.

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