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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.
41

Multi-vehicle Stochastic Fundamental Diagram Consistent with Transportations Systems Theory

Cantarella, Giuio Erberto, Cipriani, Ernesto, Gemma, Andrea, Giannattasio, Orlando, Mannini, Livia 23 June 2023 (has links)
This paper describes a general approach to the specification the stable regime speed-flow function, for motorways, as a part of the stable regime Stochastic Fundamental Diagram consistent with main assumptions of Transportation Systems Theory. Main original elements are: • Specification of speed-flow functions consistent with travel time function, such as BPR-like functions; • Calibration from disaggregate data, say data from single vehicle trajectories; • Specification of the speed r. v. distribution consistent with those used in RUT for route choice behavior modelling, such as Gamma, Inv-Gamma.
42

Investigating conformational changes of proteins using Förster Resonance Energy Transfer

Balloi, Eleonora January 2015 (has links)
Förster Resonance Energy Transfer (FRET)-based techniques are gaining an increasing importance in cell biology and cell-matrix adhesion studies because they allow both the detection of conformational changes of target proteins and their localisation in cells. Frequency Domain-Fluorescence Lifetime Microscopy (FD-FLIM) is currently considered one of the most reliable methods to measure FRET in live cells. However, due to its dependence on many technical prerequisites, its use is not yet widespread. The purpose of this work was to first establish FD-FLIM measurements of FRET on a new FD-FLIM microscope module. Then we aimed to apply FD-FLIM-FRET measurements to the study of conformational changes of the cell matrix-adhesion proteins vinculin and integrin and of the growth factor receptor Tie-2. In the first part of the work, published FRET probes including distance-sensors and two sets of vinculin-based probes were extensively tested with FD-FLIM, sensitised emission and ratiometric FRET. FD-FLIM was shown to be the most accurate method in approximating molecular distances between fluorophores. Moreover this study unveiled specific caveats associated with both existing vinculin FRET probes. FD-FLIM was then used to study conformational changes of the extracellular matrix receptor alphavβ3 integrin and of the angiopoietin receptor Tie-2 using specific FRET probes designed by us. While data showed that the alphav-integrin-FRET probe localised to adhesion sites, more experiments will be required to evaluate its full functionality. The Tie-2-FRET probe was fully functional and, upon ligand binding, allowed the detection of a bending movement of the extracellular domain towards the cell membrane. Finally, a combination of FRET, immunofluorescence and tension release experiments were used to show that intracellular tension is not required to maintain integrins in their activated conformation. However, intracellular tension is required to recruit other key proteins such as vinculin, talin and tensin to adhesions sites. Overall this work demonstrates the importance of FD-FLIM-FRET as a tool to investigate conformational changes of adhesion proteins and transmembrane receptors within the cell environment.
43

Psychopathy: correlates of the MMPI-2-RF and the three-factor model of psychopathy

Hall, Katherine Achsah Lisa 01 August 2018 (has links)
Psychopathy is a personality disorder characterized by antisocial deviance in the context of interpersonal and emotional detachment. The study of psychopathy in non-forensic samples is an area of growing interest, but one that is limited by the fact that most large-scale epidemiological studies, which collect a wealth of data that could further elucidate the phenotypic correlates, constructs, assessments, and etiologic mechanisms in psychopathy, typically do not include direct assessment of psychopathy construct or measurements. However, if facets of psychopathy could be predicted from other measures, such as broadband inventories of normal personality that are often administered in large-scale investigations, data from college epidemiological studies could be brought to bear light on the study of psychopathy. This study is two-fold in the investigation of psychopathy. First, the present study replicated the work of Sellbom and colleagues (2012) three-psychopathy scales derived from the Minnesota Multiphasic Personality Inventory-2-Restructured Form (MMPI-2-RF). These scales were developed to assess psychopathy as conceptualized in the PPI-R and include Global Psychopathy (Py-T), Impulsive-Antisociality (Py-IA) and Fearless-Dominance (Py-FD). Second, the present study built upon the three-psychopathy scales by investigating psychopathy’s construct in relation to Cooke and Michie’s (2001) three-facto model. A sample of 151 participants from a Midwestern university were administrated the PPI-R and MMPI-2-RF. The MMPI-2-RF three scales and construct of psychopathy were evaluated using bivariate correlations. Results support previous studies, regarding the Py-T, Py-IA, and Py-FD scales and the three-factor model of psychopathy.
44

Quantitative Measurement of Cerebral Hemodynamics During Activation of Auditory Cortex With Single- and Multi-Distance Near Infrared Spectroscopy

Mohammad, Penaz Parveen Sultana 29 June 2018 (has links)
Functional Near Infrared Spectroscopy (fNIRS) is a safe, low-cost, non-invasive opti-cal technique to monitor focal changes in brain activity using neurovascular coupling and measurements of local tissue oxygenation, i.e., changes in concentrations of oxygenated hemoglobin (HbO) and deoxygenated hemoglobin (HbR)[42]. This thesis utilizes two fNIRS approaches to measure hemodynamic changes associated with functional stimulation of the human auditory cortex. The first approach, single-distance continuous wave NIRS (CW-NIRS) utilizes relatively simple instrumentation and the Modified-Beer Lambert (MBL) law to estimate activation induced changes in tissue oxygenation (∆CHbO and ∆CHbR)[17]. The second more complex approach, frequency domain NIRS (FD-NIRS), employs a photon diffusion model of light propagation through tissue to measure both baseline (CHbO and CHbR), and stimulus induced changes in oxygenated and deoxygenated hemoglobin[10]. FD-NIRS is more quantitative, but requires measurements at multiple light source-detector separations and thus its use in measuring focal changes in cerebral hemodynamics have been limited. A commercial FD-NIRS instrument was used to measure the cerebral hemodynamics from the right auditory cortex of 9 adults (21 ± 35 years) with normal hearing, while presented with two types of auditory stimuli: a 1000 Hz Pure tone, and Broad band noise. Measured optical intensities were analyzed using both MBL and photon diffusion approaches. Oxygenated hemoglobin was found to increase by 0.351 ± 0.116 µM and 0.060 ± 0.084 µM for Pure tone and Broad band noise stimuli, when analyzed by the MBL method at the ‘best’ source-detector separation. On average (across all sources), MBL analysis estimated an increase in CHbO of 0.100±0.075 µM and 0.099±0.084 µM respectively for Pure tone and Broad band noise stimulation. In contrast, the frequency domain analysis method estimated CHbO to increase by −0.401 ± 0.384 µM and −0.031 ± 0.358 µM for Pure tone and Broad band noise stimulation respectively. These results suggest that although more quantitative, multi-distance FD-NIRS may underestimate focal changes in cerebral hemodynamics that occur due to functional activation. Potential reasons for this discrepancy, including the partial volume effect, are discussed.
45

Hybrid Time-Domain Methods and Wire Models for Computational Electromagnetics

Ledfelt, Gunnar January 2001 (has links)
No description available.
46

A “Divide-by-Odd Number” Injection-Locked Frequency Divider.

Asghar, Malik Summair January 2013 (has links)
The use of resonant CMOS frequency dividers with direct injection in frequencysynthesizers has increased in recent years due to their lower power consumptioncompared to conventional digital prescalers. The theoretical and experimentalaspects of these dividers have received great attention. This masters thesis workis a continuation of earlier work, based on the fundamentals of Injection-LockedFrequency Dividers (ILFD’s). The LC CMOS ILFD with direct injection is wellknownfor its divide-by-2 capability. However, it does not divide well by oddnumbers. The goal of this master thesis work is to modify the LC CMOS ILFDwith direct injection so that it can divide equally well by odd and even integers.In this master thesis report, an introduction to the basic concepts behindInjection-Locked frequency dividers is first presented. Some of the previous workand the background of a reference LC CMOS ILFD design are studied. The author,studied the reference design, and the experimental setup used for characterizingit’s locking behavior. The algorithm used to characterize the locking behavior ofthis ILFD are explored to reproduce the results for divide-by-even numbers for theexisting ILFD topology. Using a Spice model these results are also reproduced insimulations.Over the years, numerous ILFD circuit topologies have been proposed, most ofwhich have been optimized for division by even numbers, especially divide-by-2.It has been more difficult to realize division by odd numbers, such as divide-by-3.This master thesis work develops a simple modification to an LC CMOS injectionlocked frequency divider (ILFD) with direct injection, which gives it a wide lockingrange both in the “divide-by-odd number” mode and in the conventional “divideby-even number” regime, thereby opening up applications which require frequencydivision by an odd number. The work presents the circuit architecture, SPICEsimulations and experimental validation.
47

Millisecond H/D Exchange Combined with Electrospray Ionization Mass Spectrometry to Study Protein¡¦s Structure

Lin, Hsuan-Chung 03 August 2004 (has links)
none
48

Fabrication of Integrated Nebulizer Nozzle Plate Utlizing Micro-molding for FD- ESI Mass Spectrometry

Chang, Chien-chung 01 July 2005 (has links)
This study presents a novel concept to integrated nebulizer nozzle plate for FD-ESI (Fused-droplet Electrospary Ionization Mass Spectrometry) using modified LIGA process. This fabrication technique can reduce the production cost of current nozzle plate. It comprises of multi-exposure and single develop (MESD) process, the extra-hard Ni-Co (Nickel-Cobalt) electroforming and thin-wall plastic microinjection molding. The template of nozzle plate is patterned using dry film and MESD process. Later, the template is transferred into metal Ni-Co mold by electroplating. In this study, the technique of extra-hard Ni-Co alloy electroplating process with Hardness of Vickers over (HV) 550 is developed. Then with the stiffness of Ni-Co mold, it can withstand high injection speed. Thin-wall microinjection molding process with short cycle time to fabricate nozzle plate can be finished. Liquid crystal polymer (LCP) is used for thin-wall microinjection molding process. In order to make efficiently atomization, we used ANSYS to optimize PZT actuator. Besides, the work of nebulizer with FD-ESI was demonstrated in this study. a novel design of nozzle plate.
49

Selective Listening Point Audio Based on Blind Signal Separation and Stereophonic Technology

TAKEDA, Kazuya, NISHINO, Takanori, NIWA, Kenta 01 March 2009 (has links)
No description available.
50

Application and Development of Fused-Droplet Electrospray Mass Spectrometry

Chang, Der-Yeou 29 June 2000 (has links)
none

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