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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.
291

Fair-Value Accounting of Derivatives and the Heterogeneity of Investor Beliefs

Dorminey, Jack 21 April 2009 (has links)
Using a sample of 51 banking organizations, I examine the effect of the Statement of Financial Accounting Standard 133 on the belief heterogeneity of market participants and how this heterogeneity affects abnormal trading volume surrounding earnings announcements. SFAS 133 is the first standard to require that all derivatives be recognized at fair-value and that the fluctuations in derivative fair-values be reported in either net income or other comprehensive income. The behavior of derivative instruments and the fair-valuation and treatment prescribed by SFAS 133 are complex. Due to the underlying complexity of both derivatives and the accounting treatment prescribed by the SFAS 133 standard, I expect that investors may have differing interpretations of the newly provided information. My hypothesis is that the income effects arising from the fair-value accounting for derivatives (SFAS 133) are associated with an increase in differing beliefs among individuals. I find that the income effects of SFAS 133 are significantly and positively related to belief heterogeneity among investors. The net income and other comprehensive income effects of SFAS 133 are significantly and positively related to increasing levels of abnormal trading volume surrounding earnings announcements. Additionally, levels of SFAS 133 net income is positively and significantly associated with three measures of belief heterogeneity derived from analysts’ forecasts. In an extended analysis I model the SFAS 133 income effects on abnormal volume using the three belief heterogeneity measures as the conduit. I find support for two of the three heterogeneity measures acting as a conduit for the effect of the SFAS 133 related income measures on abnormal volume. The results of this study indicate that, while the recognized fair-value of derivatives is value relevant to equity prices (Ahmed, Kilic, & Lobo, 2006), the income effects of the same financial standard causes heterogeneity in beliefs about the firm. This suggests that, at least in the case of derivative fair-values, there exists a trade-off between value relevance and the strength of consensus surrounding beliefs in the market.
292

Amélioration des techniques de volumétrie, tant au niveau technique et numérique, et étude des variations du volume cellulaire lors de chocs hypotoniques

Groulx, Nicolas January 2006 (has links)
Mémoire numérisé par la Direction des bibliothèques de l'Université de Montréal.
293

Regulation of Volume by Spermatozoa and Its Significance for Conservation Biology

Barfield, Jennifer 08 August 2007 (has links)
Reproductive science plays an important role in conservation biology. Quantitative studies of basic reproductive biology in wildlife are critical for the development of successful assisted reproductive technologies. Investigation of the volume regulatory mechanism of spermatozoa could produce options to improve the cryopreservation of spermatozoa and provide a non-hormonal contraceptive option for men, both of which could have significant impacts on global biodiversity preservation. Volume regulation of somatic cells involves the movement of osmolytes through various channels, including potassium channels. The potassium channels involved in volume regulation of human, monkey, and murine spermatozoa were investigated. Flow cytometry was used to gauge the sensitivity of the volume regulatory process of spermatozoa to various potassium channel inhibitors and a simultaneous hypotonic challenge. Channels potentially involved in regulatory volume decrease of spermatozoa varied with species but included voltage-gated (Kv) channels 1.4, 1.5, 1.7, 4.1, 4.2 and 4.3 as well as TWIK1, TWIK2, TASK1, TASK2, TASK3, TREK2 , and minK. The presence of some of these channels was confirmed by western blotting and immunocytochemistry. Changes in the motility patterns of human and monkey spermatozoa in the presence of potassium channel inhibitors during hypotonic stress were also observed, suggesting a relationship between volume regulation and motility. To evaluate potential organic osmolytes involved in, and compare effects of CPAs on, volume regulation, the isotonicity of murine epididymal spermatozoa was measured using a null point method. Spermatozoa were then exposed to high concentrations of various osmolytes and cryoprotective agents in isotonic medium to evaluate which compounds were able to penetrate the sperm plasma membrane. The osmotic responses of spermatozoa from strains of mice known to have spermatozoa of high (B6D2F1) and low (C57BL6) post-thaw fertility were compared during various osmotic challenges in various media. These experiments indicated that spermatozoa from B6D2F1 mice may have better volume regulation capabilities than spermatozoa from C57BL6 mice, suggesting that better post-thaw fertility of murine spermatozoa could be influenced by the volume regulatory process. The knowledge gained from these experiments could contribute to improved sperm handling and preservation techniques and be used to develop non-hormonal male contraceptives based on inhibiting volume regulation.
294

Investigation of volume and product mix flexibility in batch production

Arbabi, Mohammad Reza January 2015 (has links)
Abstract Today’s business environment involves a globalised market, greater than before competition and more challenging customers, all factors which contribute to higher uncertainty and variability. Manufacturing flexibility is becoming more important in order to cope with the complexity of products through frequency volume changes and evaluations of the technological requirements of products. The research for this thesis was performed within a subcontractor company, Laserkraft AB, who focus on laser cutting, turning and welding processes in their production. The company utilises a variety of volume and product mixes, which is in correlation with the objective of this study. The purpose of this research was to investigate the common source drivers in order to achieve volume and product mix flexibility on batch production systems. First, a literature review was conducted in order to build the framework of common source factors between volume and product mix flexibility. Then, a single case study was conducted to examine the outcomes of framework on batch production. In this case, qualitative techniques included interviews and an observation of the shop floor. The analysis of this study was conducted with empirical research on a case study and theoretical framework from literature. From the literature stand point; it was found that flexible manufacturing competencies (FMC) and strategic flexibility approaches are two main elements to determine internal source drivers between volume and product mix flexibility. The groups of common source factors were then analysed with respect to characteristics of batch production systems at the chosen company. A comparison between the framework and the empirical findings identified source drivers in order to achieve volume and product mix flexibility. Due to the limited nature of the study, all source factors that have an impact on achieving volume and product mix flexibility might not be presented in this thesis. Besides, it is difficult to generalise the result on a single case study. As a result, each organisation and industry refers to their product, process and type of layout, and requires a group of practices to achieve volume and product mix flexibility. This thesis concludes with the top three common source factors between volume and product mix flexibility such as: set-up time reduction, multi-trained employees and advanced manufacturing technology.
295

Revealing the Physics of Multiphase Galactic Winds Through Massively-Parallel Hydrodynamics Simulations

Schneider, Evan Elizabeth, Schneider, Evan Elizabeth January 2017 (has links)
This thesis documents the hydrodynamics code Cholla and a numerical study of multiphase galactic winds. Cholla is a massively-parallel, GPU-based code designed for astrophysical simulations that is freely available to the astrophysics community. A static-mesh Eulerian code, Cholla is ideally suited to carrying out massive simulations (> 2048 ³ cells) that require very high resolution. The code incorporates state-of-the-art hydrodynamics algorithms including third-order spatial reconstruction, exact and linearized Riemann solvers, and unsplit integration algorithms that account for transverse fluxes on multidimensional grids. Operator-split radiative cooling and a dual-energy formalism for high mach number flows are also included. An extensive test suite demonstrates Cholla's superior ability to model shocks and discontinuities, while the GPU-native design makes the code extremely computationally efficient - speeds of 5-10 million cell updates per GPU-second are typical on current hardware for 3D simulations with all of the aforementioned physics. The latter half of this work comprises a comprehensive study of the mixing between a hot, supernova-driven wind and cooler clouds representative of those observed in multiphase galactic winds. Both adiabatic and radiatively-cooling clouds are investigated. The analytic theory of cloud-crushing is applied to the problem, and adiabatic turbulent clouds are found to be mixed with the hot wind on similar timescales as the classic spherical case (4-5 t_cc) with an appropriate rescaling of the cloud-crushing time. Radiatively cooling clouds survive considerably longer, and the differences in evolution between turbulent and spherical clouds cannot be reconciled with a simple rescaling. The rapid incorporation of low-density material into the hot wind implies efficient mass-loading of hot phases of galactic winds. At the same time, the extreme compression of high-density cloud material leads to long-lived but slow-moving clumps that are unlikely to escape the galaxy.
296

Acute Endocrine Responses to Rest Redistribution with Heavier Loads in Resistance-Trained Men

Chae, Sungwon 08 1900 (has links)
The purpose of this study was to investigate endocrine responses to redistribution with heavier loads (RR+L) during back squat (BS) exercise in resistance-trained men. Ten men (mean±SE; 23±2 years, 175.6±2.0 cm, 78.0±3.4 kg, 4±1 training years) were assigned using randomization to either RR+L (4 sets of (2×5 repetitions) of BS with 30 s intra-set and 90 s inter-set rest using 75% of their 1RM) or traditional sets (TS; 4 sets of 10 repetitions of BS with 120 s inter-set rest using 70% of their 1RM). Fasted blood samples were collected pre-exercise (PRE), immediately post-exercise (IP), and 5 (+5), 15 (+15), and 30 (+30) minutes post-exercise to analyze the concentrations of testosterone (T), growth hormone (GH), cortisol (C), and blood lactate (BL). Two-way ANOVAs with repeated measures were used (p≤0.05). A main effect of condition (p=0.023) was observed for BL (RR+L; 5.9±0.5 vs TS; 6.7±0.4 mmol/L). A main effect of time point (p≤0.001) was observed for T, GH, C, and BL. T was greater at IP (8.8±1.1), +5 (9.0±1.1), +15 (8.5±1.0), and +30 (8.0±1.0) than PRE (7.1±0.8 ng/mL). GH was greater at IP (58.3±12.7), +5 (62.8±12.7), +15 (67.9±13.3), and +30 (52.8±11.2) than PRE (3.6±1.6 µIU/mL). C was greater at +15 (25.5±2.9) and +30 (25.6±2.7) than PRE (20.0±2.7 µg/dL). BL was greater at IP (8.6±0.6), +5 (8.2±0.6), +15 (7.4±0.5), and +30 (5.8±0.5) than PRE (1.4±0.2 mmol/L). RR+L resulted in lower BL but no differences in T, GH, and C responses compared to TS. Thus, practitioners may incorporate RR+L without affecting endocrine responses.
297

Volume rendering with Marching cubes and async compute

Tlatlik, Max Lukas January 2019 (has links)
With the addition of the compute shader stage for GPGPU hardware it has becomepossible to run CPU like programs on modern GPU hardware. The greatest benefit can be seen for algorithms that are of highly parallel nature and in the case of volume rendering the Marching cubes algorithm makes for a great candidate due to its simplicity and parallel nature. For this thesis the Marching cubes algorithm was implemented on a compute shader and used in a DirectX 12 framework to determine if GPU frametime performance can be improved by executing the compute command queue parallell to the graphics command queue. Results from performance benchmarks show that a gain is present for each benchmarked configuration and the largest gains are seen for smaller workloads with up to 52%. This information could therefore prove useful for game developers who want to improve framerates or decrease development time but also in other fields such as volume rendering for medical images.
298

Development of a Laboratory Test Method for Assessment of Crater Wear Volume on Inserts for Steel Turning

Sandberg, Joakim January 2019 (has links)
This thesis project was carried out at Sandvik Coromant in Västberga, Sweden with the purpose of developing a new laboratory test method for volumetric assessment of crater wear on inserts for steel turning. The test method was developed with the Sandvik Coromant´s existing crater wear measurement method as a starting point. Crater wear is currently measured as the projected area of exposed substrate, meaning where all coating layers have been removed. Based on earlier research on volume wear assessment, a focus variation microscope was selected to carry out 3D scans. To accurately measure the removed volume, an initial reference scan is required to capture individual variations existing on samples. The insert is then scanned after turning and compared with its reference. Factors affecting accuracy as well as possible improvements were identified as: Sample preparation, scan settings (resolution, quality) and data processing (alignment of scans, volume calculation etc.). Guiding alignment markers were created by laser ablation to help with alignment.  CloudCompare software was used to process the scanned 3D point clouds. A step by step routine was developed to ensure consistent results. The repeatability was assessed showing 8% standard deviation in volume for a shallow crater within the coating to 2% for a large crater worn into the substrate. The new method provides the possibility to measure wear while still inside the coating, which has been previously unavailable data. This enables measurement of the contribution of each specific coating layer on the wear resistance such as wear rate of a single layer instead of a combined wear rate for all layers. Detailed coating wear analysis is a valuable tool for development of optimized coatings. The developed wear measurement method was implemented on a case study which demonstrated the capabilities regarding its ability to resolve performance differences in experimental coatings. Additional wear parameters were used beside crater volume to support wear rate analysis and novel ways of representing volume wear parameters were presented.
299

Deadwood in managed and protected forest in southern Sweden : in the wake of storm

Jonsson, Paula January 2019 (has links)
Deadwood has increased over the last 25 years, but it remains unclear to what extent this is driven by forestry practices or storms. Therefore, I wanted to study the change in volume, decay stage and tree species during a 22-year period, to see if there was a correlation between increase of deadwood and storm. This study included data from southern Sweden, collected by the Swedish National Forest Inventory between 1994-2016. Deadwood in production forest have doubled over the last 25 years and almost quadrupled in protected forest. The increase does not depend on storm since much of the fallen wood was probably removed following year. In protected forest there was an increase in deadwood of broadleaved trees and a drastic decrease in Pinus sylvetstris. While in production forest, conifer trees dominate and there was no lasting effect due to the storm Gudrun (2005) on Picea abies. Hard deadwood decreased in production forest, possibly due to increased removal of branches and treetops, used as forest fuel in forest management. Possible reasons for the increase in deadwood could be the awareness in forestry, especially certification system and voluntarily set asides. Though, there is still necessary to increase the volume of deadwood in production forest, since it covers the largest parts of Swedish forests and does not seem to reach the national environment objective in 2030.
300

Avaliação da correlação entre a tomografia de impedância elétrica e o volume corrente aplicado durante o suporte ventilatório mecânico invasivo / Evaluation of the correlation between electrical impedance tomography and tidal volume applied during mechanical invasive ventilatory support

Hirota, Adriana Sayuri 12 December 2018 (has links)
Introdução: A tomografia de impedância elétrica (TIE) é uma técnica de imagem não invasiva que mensura o potencial elétrico na superfície torácica através de eletrodos colocados ao redor do tórax. Essas medidas são transformadas em uma imagem bidimensional da distribuição da impedância elétrica no tórax. Esse instrumento detecta modificações da densidade pulmonar e distribuição do volume corrente. Entretanto, é necessário melhor avaliação da sua eficiência em estimar o volume corrente (VT) a cada ciclo ventilatório. O objetivo do estudo é avaliar a correlação do volume estimado pela TIE com o VT aplicado durante o suporte ventilatório mecânico. Métodos: Inicialmente, foram estudados cinco suínos da raça Landrace. Os animais foram sedados, intubados e monitorados com a TIE. Foram aplicados volumes incrementais (100, 250, 500, 750 e 1000 mL) com a seringa de precisão em ZEEP e com PEEP de 5, 10 e 20 cmH2O, antes e depois da promoção de lesão pulmonar com lavagem com solução salina. Posteriormente, outros cinco animais foram monitorados com a tomografia computadorizada de tórax por raios X (TC) e a TIE. Foram aplicados volumes incrementais (250, 500 e 1000 mL) com a seringa de precisão em ZEEP e com PEEP de 10 e 20 cmH2O, também antes e depois da promoção de lesão pulmonar. A amplitude da variação de impedância mensurada pela TIE foi convertida em volume e foi calculado o volume de ar na TC. Análises de correlação e concordância foram realizadas com o programa \"R\" (© R Foundation for Statistical Computing). Resultados: Em ZEEP, o coeficiente de correlação entre os volumes estimado pela TIE e calculado pela TC foram, respectivamente, 0,90 e 0,96 na comparação com a seringa de precisão. O coeficiente de determinação entre a TIE e a seringa de precisão foi progressivamente reduzindo (0,90; 0,89 e 0,81 com PEEP de 5; 10 e 20, respectivamente) com o aumento do volume pulmonar promovido pela elevação da PEEP. A TC mostrou um deslocamento progressivo do conteúdo aéreo no sentido caudal com o aumento do volume pulmonar. Conclusões: Há uma boa correlação entre o volume estimado pela TIE e o VT aplicado durante o suporte ventilatório mecânico quando utilizados volumes e pressões usuais na prática clínica / Rationale: Electrical impedance tomography (EIT) is a noninvasive imaging tool that reconstructs a cross-sectional image of the lung\'s regional conductivity using electrodes placed circumferentially around the thorax. It is able to detect changes of lung air content and tidal volume (VT) distribution. However, better evaluation of its capacity to quantify VT variations is necessary. The aim of our study was to assess the correlation between volume estimated by EIT and tidal volume applied at different positive end-expiratory pressures (PEEP). Methods: Initially, in an experimental study five mechanically ventilated pigs monitored by EIT were studied. VT increments (100, 250, 500, 750 and 1000 mL) were applied with a calibrated syringe at zero end-expiratory pressure (ZEEP) and PEEP levels of 5, 10 and 20 cmH2O before and after lung-injury (induced by saline lavage). Another five pigs was monitored by EIT and x-ray computed tomography (CT). VT increments (250, 500 and 1000 mL) were applied with a calibrated syringe at zero end-expiratory pressure (ZEEP) and PEEP levels of 10 and 20 cmH2O before and after lung-injury. Lung air volume was calculated at CT scan and the amplitude of impedance change measured by EIT was converted to volume (mL). Correlation and agreement analysis was performed at \"R\" program (© R Foundation for Statistical Computing). Results: At ZEEP, volume estimated by EIT and volume calculated at CT obtained r2 = 0.90 and 0.96 respectively, when compared to calibrated syringe. The coefficient of correlation between EIT and calibrated syringe impaired (0.90; 0.89 and 0.81 with PEEP of 5; 10 and 20, respectively) with increase of the lung volume due to increased PEEP. CT showed a progressive displacement of the air content to the caudal thoracic levels with the increase of the lung volume. Conclusion: EIT is able to estimate tidal volume during mechanical ventilatory support when used volumes and pressures usually applied at bedside

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