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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.
411

Modeling of Multibody Dynamics in Formula SAE Vehicle Suspension Systems

Bansode, Swapnil Pravin 05 1900 (has links)
Indiana University-Purdue University Indianapolis (IUPUI) / Indiana University–Purdue University Indianapolis student team Jaguar has been participating in the electric Formula SAE (FSAE) vehicle competitions in the past few years. There is an urgent need to develop a design tool for improving the performance of the vehicle. In this thesis, multibody dynamics (MBD) models have been developed which allow the student team to improve their vehicle design, while reducing the required time and actual testing costs. Although there were some studies about MBD analyses for vehicles in literature, a detailed modeling study of key parameters is still missing. Specifically, the effect of suspension system on the vehicle performance is not well studied. The objective of the thesis is to develop an MBD based model to improve the FSAE vehicle’s performance. Based on the objective and knowledge gap, the following research tasks are proposed: (1) MBD modeling of current suspension systems; (2) Modification of suspension systems, and (3) Evaluation of performance of modified suspension systems. The models for the front suspension system, rear suspension system, and full assembly are created, and a series of MBD analyses are conducted. The parameters of the vehicle by conducting virtual tests on the suspension model and overall vehicle model are studied. In this work, two main virtual tests are performed. First, parallel wheel travel test on suspension system, in which the individual suspension system is subject to equal force on both sides. The test helps understand the variation in stability parameters, such as camber angle, toe angle, motion ratio, and roll center location. Second, skid-pad test on full assembly of the vehicle. The test assists in understanding the vehicle’s behavior in constant radius cornering and the tire side slip angle variation, as it is one of the important parameters controlling alignment of the vehicle in this test. Based on the vehicle’s dynamics knowledge obtained from the existing vehicle, a modified version of the FSAE vehicle is proposed, which can provide a better cornering performance with minimum upgrades and cost possible. Based on the results from the parallel wheel travel test and skid-pad test, the lateral load transfer method is used to control the vehicle slip, by making changes to the geometry of the vehicle and obtaining appropriate roll center height for both front and rear suspension system. The results show that the stiffness in front suspension system and rear suspension system are controlled by manipulating roll center height. This study has provided insightful understanding of the parameters and forces involved in suspension system and their variations in different events influencing vehicle stability. Moreover, the MBD approach developed in this work can be readily extended to other commercial vehicles and sports vehicles.
412

Development and validation of open-source software for DNA mixture interpretation based on a quantitative continuous model / 定量的連続性モデルに基づくDNA混合試料解析用オープンソースソフトウェアの開発と検証

Manabe, Sho 26 March 2018 (has links)
京都大学 / 0048 / 新制・課程博士 / 博士(医科学) / 甲第21024号 / 医科博第85号 / 新制||医科||6(附属図書館) / 京都大学大学院医学研究科医科学専攻 / (主査)教授 川上 浩司, 教授 黒田 知宏, 教授 森田 智視 / 学位規則第4条第1項該当 / Doctor of Medical Science / Kyoto University / DFAM
413

AN INVESTIGATION OF VARIABLES CONTRIBUTING TO DISORDERED GAMBLING AND SLOT MACHINE PLAY

Loukus, Amy Katherine 01 May 2017 (has links) (PDF)
Problem gambling is a growing social concern that results in debt, lost jobs, broken families, and at times, suicide. Slot machines are the most popular and most addictive form of gambling, generating nearly 70% of annual profits for the commercial casino industry in North America. Behavioral researchers have identified variables that establish and maintain problem gambling on slot machines, and the data reveal characteristics that influence preference for specific games, and subsequently, time spent engaged with specific machines. A degree of variability has been reported in the outcomes observed across participants and studies; such variability may be influenced by generic features of the games used by researchers utilizing a “one machine suits all” approach to slot research, i.e., within most studies a single machine is used for all participants rather than chosen according to participant preference for the machine or features therein. The following set of studies aimed to investigate variables related to slot machine selection, gambler preference for structural characteristics, and the reinforcing effectiveness of the machine on gambling behavior. The first of three experiments evaluated participant preference for functional and structural characteristics of popular three-, four- and five-reel electronic Vegas-style slot machines according to (a) a Likert rating scale of attitudes toward the machines, (b) forced ranking of most-preferred machines, and (c) a paired-stimulus preference assessment. Experiment II utilized a series of multiple schedules randomized across participants to examine differences in the rate of play when participants gambled on their most- and least-preferred machines. In Experiment III, the reinforcing effectiveness of the machines was evaluated. Participants engaged in an arbitrary task to gain access to their highest- and least-preferred machines as indicated in Experiment I. Response effort during the work task was evaluated under a progressive ratio schedule of reinforcement to determine the degree to which the individual would work to gain access to the machine. Participant break points were compared across the two conditions. Results of Experiment I yielded significant differences in the degree to which participants rated the machines: three-reel machines and those displaying a win were rated significantly higher in the attitude assessment when compared to four- or five-reel machines, and when compared to those with a loss, respectively. During the forced ranking procedure, participants again selected three-reel machines significantly more frequently in their “top five” favorite machines than four- or five-reel options. Last, when subjected to the paired stimulus preference assessment, participants selected three-reel machines on a significantly higher percentage of trials than five-reel alternatives. Results of Experiment II demonstrated that rate of play on high-preference machines is on average, faster than rate of play on lower-preference machines, and results from Experiment III yielded on average, higher break points in participant responding when offered the opportunity to gamble on high-preference slot machines following a response requirement than when offered a low-preference option; however, the average rate of response on the work task that led to machine access was lower during high-preference conditions than low-preference conditions. Implications of these findings for the gambling literature and for the effective prevention and treatment of disordered slot machine gambling are discussed.
414

Experimental Assessment of Butomus Umbellatus L. Growth and Expansion Using a Mesocosm Approach

Carter, Christian 15 August 2014 (has links)
Over the last century, flowering rush (Butomus umbellatus L.: Butomaceae) has escaped its native Eurasian range and has become a problematic species in North America. As an aquatic invasive species, flowering rush has degraded native wetlands and has interfered with human water usage. Although experimental work has been done regarding the reproductive biology of the species, few empirical studies regarding the ecology of the species have been conducted. The research reported here demonstrates that flowering rush is capable of aggressive clonal growth and propagation, and can perform well along a depth gradient from zero to 132cm. Proper management and control of invasive species relies on sound ecological knowledge of the target species, and this work aims to help gather that information.
415

Hedging the Price Risk of Crop Revenue Insurance through the Options Market

Tiwari, Sweta 11 August 2017 (has links)
Crop revenue insurance is an exception in the insurance industry offering a guarantee subsuming a highly systematic risk- price variability. This study examines whether crop insurance companies could use put and call options to hedge the price risk present in corn revenue insurance. The behavioral model used to examine hedging optimization behavior of a crop producer with crop insurance by Coble, Heifner, and Zuniga (2002) is modified to examine optimal hedge ratio of a company selling revenue insurance. The crop insurance summary of business from 1985-2015 for corn revenue policies was simulated. Corn futures prices were collected from the Commodity Research Bureau databases. Results show that net return from call and put options can hedge indemnities paid by corn RP and RP-HPE resulting from the price variability in some scenario. This suggests hedging the price risk of corn revenue insurance through options could be a viable practice for crop insurers.
416

An analysis of solution strategies and processing times in ratio and proportion problems /

Gajewski, Stanley January 1980 (has links)
No description available.
417

Classification of Copper Deposits Using Copper, Gold, Silver Ratios

Binney, W. Paul 05 1900 (has links)
An attempt was made in this study to classify copper deposits using the ratio of copper, gold and silver in the deposits. Data were accumulated from a literature search and neutron activation analysis of samples. Triangular diagrams were plotted and fields for each type of deposit were defined. Porphyry, volcanogenic, and sedimentary fields were most easily defined due to the amount and quality of data available for these deposits. It is found that the size of the field for any type of deposit is a function of its mineralogy. This is illustrated by the data spread for the copper and lead-zinc zones in volcanogenic deposits. A clear separation of deposit types could not be obtained due to a partial overlap of the data fields; however, it is suggested that further work using more metals might yield a clear separation of deposits. / Thesis / Bachelor of Science (BSc)
418

Assessing Structure-Function Relationships in a Mouse Model of Emphysema using Ventilation and Perfusion (V/Q) SPECT/CT

McCurry, Cory January 2015 (has links)
Emphysema is a condition of the lung characterized by abnormal, permanent enlargement of the airspaces distal to the terminal bronchiole, accompanied by a destruction of their walls. The primary pathogenesis of emphysema is poorly understood. One of the major issues of COPD is that no diagnostic tests are sensitive enough to detect early disease. Standard pulmonary function tests (PFTs) do not explain the underlying pathophysiology of airflow limitation, nor do they provide information on how COPD may be affecting pulmonary blood flow. Functional imaging, specifically ventilation and perfusion (V/Q) Single Photon Emission Computed Tomography (SPECT), is a sensitive tool that can provide information on pulmonary function in different lung regions. When V/Q images are co-registered to CT, regional analysis can be coupled to structural information. The objective of this study was to examine how emphysematous change identified and localized by CT density based thresholds affects lung function as measured by V/Q SPECT in a mouse model of the disease. A dose response study was conducted where Female BALB/c mice were exposed intranasally to 0.0, 0.5, 2.5 and 5.0 units (U) of porcine pancreatic elastase (PPE). V/Q SPECT/CT scanning was performed 45 days post exposure, followed by measurement of lung compliance using the Flexivent® rodent ventilator 46 days post exposure. Whole lung slice analysis software was used to quantify airspace enlargement and alveolar capillary density from histological sections of the lung. CT pulmonary angiography (CTPA) was also performed on controls and mice exposed to 5 U PPE to examine vascular density. In this mouse model of emphysema, V/Q SPECT was useful in quantitatively examining how ventilation and perfusion is affected in mild and severe emphysema while providing evidence of low log(V/Q) ratio in otherwise normal lung densities. This could be caused by airflow obstruction as a result of widespread narrowing or loss of small conducting airways. Low log(V/Q) ratio is caused by mild emphysema indicating airflow obstruction or dysfunctional hypoxic vasoconstriction in underventilated regions of the lung. The majority of severely emphysematous regions of the lung have matched but equally reduced log(V/Q), although low log(V/Q) is also present. Pulmonary hypertension in response to chronic hypoxia may explain our finding of reduced perfusion activity and vascular density in emphysematous lung, but further research is required to investigate the presence of this pathology. V/Q SPECT was also shown to be superior in the detection of emphysema compared to CT and Flexivent measured lung compliance providing evidence towards shifting the current assessment and monitoring paradigms. Due to the widespread availability of this imaging technique, it could be used to screen asymptomatic smokers for early disease and identify and locate pathology so therapies targeting the appropriate disease pathway can be prescribed. This will inevitably improve patient care. / Thesis / Master of Science (MSc)
419

Impacts of Independence Day Fireworks on Pollution Levels of Atmospheric Polycyclic aromatic Hydrocarbons (PAHs) in the U.S.

Jia, Chunrong, Xue, Zhuqing, Fu, Xianqiang, Sultana, Fariha, Smith, Larry J., Zhang, Yueqian, Li, Ying, Liu, Bian 15 November 2020 (has links)
Fireworks on Independence Day have been identified as a nationwide but short-term source of particulate matter in the U.S. No study has specifically examined their impacts on ambient polycyclic aromatic hydrocarbons (PAHs). Based on data between 1990 and 2019 in the Air Quality System, we identified 76 unique events that had PAH measurements on both July 4th days and control days (within 15 days before and after July 4th). We compared concentrations and diagnostic ratios of 16 priority PAHs between event and control days using Wilcoxon signed-rank tests and multivariable regressions. A local PAH monitoring campaign was conducted at eight sites in Memphis, Tennessee, to obtain a close observation of PAH changes. The national geometric mean (GM) concentrations of summed 16 PAHs (ΣPAHs) were similar between event and control days (48.1 ng/m3 vs. 52.8 ng/m3, p = 0.98). About a quarter of events had elevated PAH concentrations compared with control days. Higher diagnostic ratios were found on event days, suggesting more contributions from fireworks sources. PAHs on July 4th were unlikely to cause acute or chronic health effects. While the local monitoring showed a 15% increase of ΣPAHs on July 4th, the difference was not significant (p = 0.62). Elevated PAH concentrations occurred at sites near fireworks sources and without major traffics, but did not occur at those in remote areas or near major interstate highways. In conclusion, this study finds that Independence Day fireworks have negligible impacts on atmospheric PAHs at the national level, and are unlikely to pose significant health risks. The firework effect is localized within a limited geographic scale, suggesting potential needs for local monitoring and control programs.
420

Aktuální otázky vazby v českém trestním řízení / Current issues of custody within Czech criminal proceedings

Benediktová, Eliška January 2021 (has links)
Current issues of custody within Czech criminal proceedings Abstract This submitted thesis describes custody's current issues within Czech criminal proceedings. The custody is an established and irreplaceable institute that has been for a long time a traditional part of criminal proceedings. Due to the nature of this institute, representing a major interference with personal freedom of the individual, it is still widely discussed not only by experts but also attracts the attention of the general public. The thesis itself consists of five consecutive chapters. The first chapter defines the concept and purpose of the custody, considering its basic principles. The following second chapter includes a brief description of custody's historical development in the Czech Republic, but the chapter also serves as an introduction to understanding the current legislation. In addition, the valid regulation is the one of 1961, which has undergone several changes since its adoption. The third chapter deals with the material concept of custody law, i.e. the legal conditions for the custody imposition and the analysis of individual reasons for it, trying to capture the bottlenecks of the related law. The fourth chapter describes some aspects of formal custody law, which characterizes the processes of authorized bodies in...

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