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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.
371

Use of near-infrared spectroscopy to identify trends in regional cerebral oxygen saturation in horses

McConnell, Emma Jane January 2013 (has links)
This dissertation focuses on the use of near-infrared spectroscopy (NIRS) to identify trends in regional cerebral oxygen saturation (rSO2) in both conscious and anaesthetised healthy horses. A cerebral/somatic oximeter sensor recorded rSO2 from the dorsal sagittal sinus of 6 healthy horses. Values for rSO2, arterial and venous oxygen and carbon dioxide tensions (PaO2, PvO2, PaCO2 and PvCO2 respectively), along with arteriovenous oxygen saturations (SavO2) were recorded in unsedated (recording period [RP] 1), sedated (RP2), and anaesthetised horses (RP3-5); and during recovery (RP6-8). During anaesthesia, horses were ventilated to achieve states of normo- (RP3), hyper- (RP4) and hypocapnoea (RP5). Overall mean ± s.d. values for rSO2, PaO2, PvO2, PaCO2, SavO2 and mean arterial pressure (MAP) varied significantly by RP. Significant decreases in rSO2 were identified between RP1 and the post-anaesthetic periods however no significant differences in rSO2 values were identified between RP1 and the intra-anaesthesia periods. Regional cerebral oxygen saturation was significantly correlated with PaO2, PvO2 and SavO2. No correlation was identified between rSO2 and lactate concentration. This is the first study to identify trends in rSO2 in horses using NIRS. A significant positive correlation was identified between rSO2 and PvO2, suggesting that alterations in cerebral oxygenation may be reflected in jugular PvO2. Results of this study demonstrate that NIRS can be used during general anaesthesia to monitor trends in rSO2 in healthy horses, and has the potential to alert clinicians to cerebral desaturation events when used in a clinical setting. / Dissertation (MMedVet)--University of Pretoria, 2013. / gm2014 / Companion Animal Clinical Studies / unrestricted
372

Phase retrieval for object and probe in the optical near-field

Robisch, Anna-Lena 08 September 2015 (has links)
No description available.
373

Quantitative evaluation of starch determination in feed samples using Near Infra-red Reflectance

Mapekula, Nwabisa Nolwazi. January 2012 (has links)
In an attempt to reduce the costs and turn around times experienced with outsourcing starch analysis in finished feed products, the company decided to invest in a NIR instrument to carry out such analyses in house. The particular instrument purchased by the company comes with a build in calibration for specific finished feed products and the main objective of this investigation was to evaluate whether the instrumentation and build in calibration gives reliable analyses of a finished poultry feed. The results obtained showed that : - The NIR results obtained have a positive bias compared to the theoretical (formulation specified value) and also to the value obtained by enzymatic starch analysis. - Despite the positive bias, the starch values were well within the allowable limits - Repeatability measurements on the data generated by two different analysts showed that while the percentage relative standard deviations obtained (< 1.0 percent) were well within the company specifications of percentage RSD < 5.0 percent, the inter sample repeatability showed small, but significant variation. - The results for intermediate precision showed that there is no statistically significant difference between the results obtained by two different analysts, nor was there any difference in the results of the same samples analysed at different time periods. - Reproducibility could not be evaluated due to the lack of another instrument within the company that were similarly set up as the instrument used for the investigation. This investigation has shown that, given the restrictions enforced by the build incalibration of the NIR instrument, the use of NIR for the analyses of the finished feed product is valid, but will require that careful attention be paid to data collection procedures.
374

Near field communication in smart phones using MIFARE standards for illiterate patients

Mareli, Mahlaku 17 September 2014 (has links)
M.Ing. (Electrical And Electronic Engineering) / Patient safety in healthcare is sometimes compromised due to medical and clerical errors. These errors can increase the operational cost of healthcare if not identified and rectified speedily. They can also result in misdiagnosis, wrong treatment options being provided to patients and in the worst case may result in fatalities. Healthcare errors in medication documentation, administration, and prescription can cause incorrect medicine administration and dosage instructions for patients. Sub-Saharan Africa has the lowest percentage (adults is 59% and youth is 70%) of literacy compared to other regions of the world sitting at (adults is 84% and youth is 89%). The challenge facing illiterate patients is that they can easily make the same mistakes and may not take their medication correctly. The application of Near Field Communication (NFC) technology in healthcare has demonstrated some advantages of security, accuracy and effectiveness over other technologies. The availability of NFC in some smartphones has also encouraged the development of more applications. The main objective of this thesis is to present a solution using an Android based NFC application that enables a NFC enabled smartphone to read NFC tags placed on medication containers and be able to play the audio instructions to illiterate patients. Based on a comprehensive review of the literature on NFC applications in healthcare, this solution is the first of its kind. A set of experiments were done in an effort to understand the operation of NFC phones under different environments. The proposed application reads the NFC tag placed on the medicine container. The data read from the NFC tag is used to identify the audio file corresponding to the particular patient’s medicine instructions. If the audio instructions are not available, on the phone, it is fetched from a remote server database using an Internet connection. The application automatically plays the audio file to the patient. Three research hypotheses were tested and it was confirmed that (H1), modified NFC antenna can reduce the level of induced power in it; (H2), the NFC technology is faster and more accurate in reading tag code that Barcode technology reading the barcode; (H3), the NFC reading process of NFC tag code is not negatively affected by the amount of light in the environment it is operated in. The Barcode reading accuracy was 10% errors when operating in the environment with light brightness of 128000 lumens. When the light brightness was reduced to 8900 lumens, the Barcode accuracy errors increased to 45%.
375

Effects of a Near-Death Experience Learning Module on Grief

Foster, Ryan D. 08 1900 (has links)
The researcher examined the effectiveness of a near-death experience (NDE) learning module on reducing distressing aspects and enhancing a growth aspect of grief among bereaved adults. Participants were 22 females and 2 males; 2 identified as African American, 3 as Asian, 2 as Latina/o, and 17 as White; aged 20 to 71 years with mean age 35.3 years. In this experimental design, the researcher randomly assigned 12 participants to the experimental group and 12 participants to the waitlist no treatment control group. Participants in the experimental group received the NDE learning module intervention, which consisted of 3 sessions over consecutive weeks. Six research questions were explored. A two-factor repeated measures analysis of variance was performed on five dependent variables to determine if the two groups performed differently across time according to the pretest and posttest results of the Despair, Panic Behavior, Personal Growth, Detachment, and Disorganization subscales of the Hogan Grief Reaction Checklist (HGRC). A one-way analysis of covariance was performed on one dependent variable to determine if the groups were statistically different according to the posttest results of the Blame and Anger subscale of the HGRC. Additionally, univariate eta squared was hand calculated to determine practical significance. Findings indicated that bereaved adults who participated in the NDE learning module showed small effect size for interaction on Panic Behavior (&#951;2 = .05) and Personal Growth (&#951;2 = .05), large effect size for interaction on Detachment (&#951;2 = .15), large effect size for treatment type on Blame and Anger (&#951;2 = .15), and negligible effect size for interaction on Despair (&#951;2 < .01) and Disorganization (&#951;2 < .01). Although no statistically significant results were found for any of the dependent variables (p > .05), effect size findings indicated modest to substantial benefits of the NDE learning module intervention for bereaved adults in the form of decreased panic behavior, blame and anger, and detachment, and increased personal growth. Implications for further research beyond this initial investigation are discussed.
376

Temporal Mapping and Connectivity using NIRS for Language Related Tasks

Hall, Michael A 09 February 2012 (has links)
Near infrared spectroscopy (NIRS) is an emerging neuroimaging modality with high temporal and good spatial resolution. In this thesis, NIRS was applied to understand functionality of the fronto-temporal cortex in response to language-related tasks. A 32-channel NIRS system (Imagent ISS Inc.) was used to perform experimental studies on 15 right-handed normal adults. Block-design based Word Expression and Word Reception paradigms were independently presented to participants. Activation, functional connectivity and cortical lateralization analyses were performed. From word expression studies, results showed left anterior region (encompassing Broca) is majorly involved over right homologue and posterior regions. From the word reception studies, results showed that right posterior region (encompassing right homologue of Wernicke) is highly involved in language reception, with right anterior region (encompassing right homologue of Broca) also involved. The current study has potential future applications in surgical evaluation of language regions in populations with neurological disorders such as epilepsy, and schizophrenia.
377

Government administration in the kingdom of Saudi Arabia

Fitzgerald, George T. 01 January 1983 (has links)
No description available.
378

Evaluating motion processing algorithms for use with fNIRS data from young children

Delgado Reyes, Lourdes Marielle 01 December 2015 (has links)
Motion artifacts are often a significant component of the measured signal in functional near-infrared spectroscopy (fNIRS) experiments. A variety of methods have been proposed to address this issue, including principal component analyses (PCA), Kalman filtering, correlation-based signal improvement (CBSI), wavelet filtering, spline interpolation, and autoregressive algorithms. The efficacy of these techniques has been compared using simulated data; however, our understanding of how these techniques fare when dealing with task-based cognitive data is limited. Recently, Brigadoi et al. (2014) quantitatively compared 6 motion correction techniques in a sample of adult data measured during a simple cognitive task. Wavelet filtering showed the most promise as an optimal technique for motion correction. Because fNIRS is often used with infants and young children, it is critical to evaluate the effectiveness of motion correction techniques directly with data from these age groups. Here we examined which techniques are most effective with data from young children. The efficacy of each technique was compared quantitatively using objective metrics related to the physiological properties of the hemodynamic response using two different sets of parameters to ensure maximum retention of included trials. Results showed that targeted PCA (tPCA) and CBSI retained a higher number of trials. These techniques also performed well in direct head-to-head comparisons with the other approaches using both quantitative metrics and a qualitative assessment. The CBSI technique corrected many of the artifacts present in our data; however, this technique was highly influenced by the parameters used to detect motion. The tPCA technique, by contrast, was robust across changes in parameters while also performing well across all comparison metrics. We conclude, therefore, that tPCA is an effective technique for the correction of motion artifacts in fNIRS data from young children.
379

3D Near Isotropic Antenna in Package for IoT Applications

Su, Zhen 11 1900 (has links)
Internet of Things (IoT) is an emerging paradigm about building a massive internet to link billions of non-living things to make smart decisions for humans and improve their quality of life. For many of IoT devices, such as wireless sensor nodes dispersed in the environment, there is not much control over their placements or orientations. Thus, there is a need to develop orientation insensitive antennas that ensure reliable data transmission irrespective of devices’ positions or orientations. As billions of such IoT devices required in the future, a low-cost fabrication process suitable for mass manufacturing must be adapted. Antenna in package (AiP) concept is beneficial that the package is utilized to realize the antennas, not only saving space but also reducing the overall cost. For orientation insensitivity, antennas must be near isotropic and even have to maintain their radiation pattern for multi-bands or wide bandwidths in most applications. However, there is a dearth in the literature about design methodologies for near isotropic antennas, particularly for multi-bands near isotropic AiP designs. In addition, a near isotropic behavior is also important for polarization, particularly for CP antennas. To have simultaneous isotropy in radiation pattern and circular polarization is challenging. In the nut shell, this thesis presents theoretical models and derives conditions for wire AiP design for different specifications, single-band and dual-band near isotropic antennas, null free near isotropic antenna with wide CP coverage, and a full CP antenna with decent near isotropy (with very narrow null beam). The single-band AiP has only 5.05 dB gain variation at WiFi/BLE band and the dual-band AiP has a decent near isotropic radiation property and covers both GSM900 and GSM1800 bands. The theoretical model for null-free near isotropic antenna with wide CP coverage is presented with particle swarm optimization (PSO). The full CP antenna has a measured CP coverage of 70% with a small null in the radiation pattern. The results are promising and indicate that the conditions and methods proposed are useful for the future near isotropic AiP design. Also, this work provides designers flexibility to adjust the AiP design according to their own applications.
380

Realizace zařízení pro měření rozptylu elektromagnetického záření ve struktuře solárních článků / Realization of the device for measurement of electromagnetic waves scattering from structure of solar cells

Brilla, Pavol January 2010 (has links)
The master thesis discusses the principles, design and realization of the original device for measuring of the electromagnetic radiation scattering in the structure of solar cells. It follows the results of a previous project "Analýza optických vlastností solárných článku" (ev.n.FT-TA3/142) and as well as knowledge gained from Ing. Vladimir Grundling’s master thesis, which has been done under this project. The subject of this thesis was to make a device for measuring of the electromagnetic radiation scattering in the visible spectrum. The aim of this work is an innovation of the previous device, so that the electromagnetic radiation scattering in the near infrared spectrum can be studied. This makes the possibility to qualify the influence of the rear surface of an active part of solar cell on electromagnetic radiation scattering, i.e., on the conversion efficiency of solar energy into electric. For this reasons it was necessary to modify the device, so that we can change the radiation source and detector because of the transparency of silicon wafers for the near infrared area. The work is supported by the project „Barevné solární články s vysokou účinností pro architektonické aplikace“ (FRTI1/168) in cooperation with Solartec s.r.o.

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