• Refine Query
  • Source
  • Publication year
  • to
  • Language
  • 42
  • 24
  • 17
  • 11
  • 8
  • 8
  • 4
  • 4
  • 4
  • 3
  • 1
  • 1
  • 1
  • Tagged with
  • 149
  • 19
  • 16
  • 16
  • 15
  • 15
  • 14
  • 13
  • 12
  • 12
  • 12
  • 11
  • 11
  • 10
  • 10
  • 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.
131

Developing a methodology to account for commercial motor vehicles using microscopic traffic simulation models

Schultz, Grant George 30 September 2004 (has links)
The collection and interpretation of data is a critical component of traffic and transportation engineering used to establish baseline performance measures and to forecast future conditions. One important source of traffic data is commercial motor vehicle (CMV) weight and classification data used as input to critical tasks in transportation design, operations, and planning. The evolution of Intelligent Transportation System (ITS) technologies has been providing transportation engineers and planners with an increased availability of CMV data. The primary sources of these data are automatic vehicle classification (AVC) and weigh-in-motion (WIM). Microscopic traffic simulation models have been used extensively to model the dynamic and stochastic nature of transportation systems including vehicle composition. One aspect of effective microscopic traffic simulation models that has received increased attention in recent years is the calibration of these models, which has traditionally been concerned with identifying the "best" parameter set from a range of acceptable values. Recent research has begun the process of automating the calibration process in an effort to accurately reflect the components of the transportation system being analyzed. The objective of this research is to develop a methodology in which the effects of CMVs can be included in the calibration of microscopic traffic simulation models. The research examines the ITS data available on weight and operating characteristics of CMVs and incorporates this data in the calibration of microscopic traffic simulation models. The research develops a methodology to model CMVs using microscopic traffic simulation models and then utilizes the output of these models to generate the data necessary to quantify the impacts of CMVs on infrastructure, travel time, and emissions. The research uses advanced statistical tools including principal component analysis (PCA) and recursive partitioning to identify relationships between data collection sites (i.e., WIM, AVC) such that the data collected at WIM sites can be utilized to estimate weight and length distributions at AVC sites. The research also examines methodologies to include the distribution or measures of central tendency and dispersion (i.e., mean, variance) into the calibration process. The approach is applied using the CORSIM model and calibrated utilizing an automated genetic algorithm methodology.
132

Acculturation and health outcomes among Vietnamese immigrant women in Taiwan

Yang, Yung-Mei January 2008 (has links)
Background Recently, Taiwan has been faced with the migration of numbers of women from Southeast Asian (SEA) countries. It was estimated that the aggregate number of SEA wives in Taiwan was more than 131,000 in 2007 (Ministry of Foreign Affairs, 2006).These women are often colloquially called, “foreign brides” or “alien brides”; most of them are seen as commodities of the marriage trade, whose marriages are arranged by marriage brokers. Some women can be regarded as being sold for profit by their families. These young Vietnamese immigrant women come to Taiwan alone, often with a single suitcase, and are culturally and geographically distinct from Taiwanese peoples; the changes in culture, interpersonal relationships, personal roles, language, value systems and attitudes exert many negative impacts on their health, so greater levels of acculturation stress can be expected. This particular group of immigrant women are highly susceptible and vulnerable to health problems, due to language barriers, cultural conflicts, social and interpersonal isolation, and lack of support systems. The aims of this study were to examine the relationships between acculturation and immigrantspecific distress and health outcomes among Vietnamese transnational married women in Taiwan. This study focuses on Vietnamese intermarriage immigrants, the largest immigrant group in the period from1994 through to 2007. Methodology The quantitative study was divided into two phases: the first was a pilot study and the second the main study. This study was conducted in a communitybased health centre in the south of Taiwan, targeting Taiwanese households with Vietnamese wives, including the Tanam, Kaohsiung, and Pentong areas. This involved convenience sampling with participants drawn from registration records at the Public Health Centre of Kaohsiung and used the snowball technique to recruit 213 participants. The instruments included the following measures: (1) Socio-demographic information (2) Acculturation Scale (3) Acculturative Distress Scale, and (4) HRQOL. Questions related to immigrant women’s acculturation level and health status were modified. Quantitative data was coded and entered into the SPSS and SAS program for statistical analysis. The data analysis process involved descriptive, bivariate, multivariate multiple regression, and classification and regression trees (CART). Results Six hypotheses of this study were validated. Demographic data was presented and it revealed that there are statically significant differences between levels of acculturation and years of residency in Taiwan, number of children, marital status, education, religion of spouse, employment status of spouse and Chinese ethnic background by Pearson correlation and Kendall’s Tau-b or Spearman test. The correlations of daily activity, language usage, social interaction, ethnic identity, and total of acculturation score with DI tend to be negatively significant. In addition, the result of the one-way ANOVA supported the hypothesis that the different types of acculturation had a differential effect on immigrant distress. The marginalized group showed a greater immigrant distresses in comparison with the integrated group. Furthermore, the comparison t-test revealed that the Vietnamese immigrant women showed a lower score than Taiwanese women in HRQOL. The result showed higher acculturative stress associated with lower score of HRQOL on bodily pain, vitality, social functioning, mental health, and mental component summary. The CART procedure to the conclusion that the predictive variables for the physical component of the SF-36 (PCS) were: alienation, occupation, loss, language, and discrimination (predicted 28.8% of the total variance explained). The predictive variables for the mental component of the SF-36 (MCS) were: alienation, occupation, loss, language, and novelty (predicted 28.4% of the total variance explained). Conclusion As these Vietnamese immigrant women become part of Taiwanese communities and society, the need becomes apparent to understand how they acculturate to Taiwan and to the health status they acquire. The findings have implications for nursing practice, research, and will assist the Taiwanese government to formulate appropriate immigrant health policies for these SEA immigrant women. Finally, the application of this research will positively contribute to the health and well being of thousands of immigrant women and their families.
133

PHARMACOLOGICAL TARGETING OF FGFR SIGNALING TO INHIBIT BREAST CANCER RECURRENCE AND METASTASIS

Saeed Salehin Akhand (8771426) 29 April 2020 (has links)
Breast cancer (BC) is one of the deadliest forms of cancers with high incidence and mortality rates, especially in women. Encouragingly, targeted therapies have improved the overall<br>survival and quality of life in patients with various subtypes of BC. Unfortunately, these first-line therapies often fail due to inherent as well as acquired resistance of cancer cells. Treatment evading cancer cells can exhibit systemic dormancy in patients over a long period of time without manifesting any symptoms. In a suitable environment, these undetected disseminated tumor cells can relapse in the form of metastasis. Therefore, it is essential to understand the mechanisms of<br><div>BC recurrence and to develop durable therapeutic interventions to improve patient’s survival. In this dissertation work, we studied fibroblast growth factor receptors (FGFR), as therapeutic targets to treat the recurrence of drug-resistant and immune-dormant BC metastasis. <br></div><div><br></div><div>The HER2 subtype of BC is characterized by the overexpression of human epidermal growth factor receptor 2 (HER2), which drives elevated downstream signaling promoting tumorigenesis. Trastuzumab emtansine (T-DM1) is an antibody-drug conjugate in which an anti-HER2 antibody targets HER2 overexpressing tumor cells and delivers a highly potent microtubule inhibitor. Using novel models of minimal residual disease (MRD) following T-DM1 treatments, we found that epithelial to mesenchymal transition is a critical process for cells to persist the TDM1 treatments. The upregulation of FGFR1 may facilitate insensitivity to T-DM1. Our data also showed that FGFR1 overexpression in HER2+ tumors leads to a higher incidence of recurrence, and these recurrent tumors show sensitivity towards covalent inhibition of FGFR. <br></div><div><br></div><div>In addition to drug-induced MRD in the primary tumor sites, disseminated tumor cells (DTCs) can demonstrate dormant phenotype via maintaining an equilibrium with immunemediated tumor clearance. Factors affecting such equilibrium may contribute to the recurrence of breast cancers metastasis. We show that such immune-mediated dormancy can be modeled with the 4T07 tumors. These tumors display immune-exclusion phenotypes in metastatic pulmonary organs. The inhibition of FGFR modulates the immune cell compositions of pulmonary organs favoring anti-tumor immunity. However, inhibition of FGFR may also affect T cell receptor downstream signaling, resulting in the inhibition of cytolytic T cell’s function. Finally, we report that combination therapy using the FGFR kinase inhibitor and an immune checkpoint blockade showed effective targeting of metastatic 4T07 tumors. <br></div><div><br></div><div>FGFR signaling as a therapeutic target in various tumors has been an active focus of cancer research. In this dissertation work, we have expanded our understanding of the role of FGFR in the recurrence of drug-resistant breast cancers as well as in the maintenance of an immune evasive microenvironment promoting pulmonary growth of tumors. Moreover, we presented evidence that it is possible to repurpose FGFR targeted therapy alone or in combination with checkpoint blockades to target recurrent metastatic BCs. In the future, our novel models of minimal residual diseases and systemic immune dormancy may act as valuable biological tools to expand our understanding of the minimal residual disease and dormant tumor cells.</div>
134

Assessment of Machine Learning Applied to X-Ray Fluorescence Core Scan Data from the Zinkgruvan Zn-Pb-Ag Deposit, Bergslagen, Sweden

Simán, Frans Filip January 2020 (has links)
Lithological core logging is a subjective and time consuming endeavour which could possibly be automated, the question is if and to what extent this automation would affect the resulting core logs. This study presents a case from the Zinkgruvan Zn-Pb-Ag mine, Bergslagen, Sweden; in which Classification and Regression Trees and K-means Clustering on the Self Organising Map were applied to X-Ray Flourescence lithogeochemistry data derived from automated core scan technology. These two methods are assessed through comparison to manual core logging. It is found that the X-Ray Fluorescence data are not sufficiently accurate or precise for the purpose of automated full lithological classification since not all elements are successfully quantified. Furthermore, not all lithologies are possible to distinquish with lithogeochemsitry alone furter hindering the success of automated lithological classification. This study concludes that; 1) K-means on the Self Organising Map is the most successful approach, however; this may be influenced by the method of domain validation, 2) the choice of ground truth for learning is important for both supervised learning and the assessment of machine learning accuracy and 3) geology, data resolution and choice of elements are important parameters for machine learning. Both the supervised method of Classification and Regression Trees and the unsupervised method of K-means clustering applied to Self Organising Maps show potential to assist core logging procedures.
135

Návrh a realizace demonstračního modelu dvojítého kyvadla / Design and implementation of demonstration model "double inverted pendulum"

Slabý, Vít January 2018 (has links)
This thesis describes the process of rebuilding an experimental model of a single pendulum on a cart into the double pendulum on a cart. The control algorithm in MATLAB/Simulink environment for stabilization of the pendulum in the inverse position is designed. For this purpose, LQR state feedback control was implemented. Also method for swinging the pendulum into inverse position from stable state (swing-up) was designed. Feedforward method was utilised for swing-up control. In the thesis, functionality of these algorithms is shown.
136

Návrh a řízení modelu laboratorního dvojitého kyvadla / Design and control of laboratory double pendulum model

Kirchner, Tomáš January 2020 (has links)
Improvement of the current double inverted pendulum model on a cart as well as a new LQG control and swing-up realization are the main goal of this thesis. Movement of the cart is driven by DC motor and gear belt mechanism. At first the control algorithms were simulated in Simulink program and then also implemented into the real system with MF624 card.
137

Návrh konstrukčního řešení automatického podavače tablarů pro skladovací systém SLL LogiMat / Design of automatic feeder of movable shelfs of storage system SSL LogiMat

Stoklásek, Tomáš January 2016 (has links)
The aim of this thesis is automatic movable shelves feeder design. the feeder is part of vertical lift storage system Logimat Total weight of movable shelf is 760 kg. The technical report contains feeder design calculation, feeder’s main parts strength calculation and the design of the way of picking the movable shelf from the storage lift. The report also contains feeder’s frame strength analysis using finite element method and sensor design for motion control.
138

Rule-based analysis of throughfall kinetic energy to evaluate biotic and abiotic factor thresholds to mitigate erosive power

Goebes, Philipp, Schmidt, Karsten, Stumpf, Felix, von Oheimb, Goddert, Scholten, Thomas, Härdtle, Werner, Seitz, Steffen 17 September 2019 (has links)
Below vegetation, throughfall kinetic energy (TKE) is an important factor to express the potential of rainfall to detach soil particles and thus for predicting soil erosion rates. TKE is affected by many biotic (e.g. tree height, leaf area index) and abiotic (e.g. throughfall amount) factors because of changes in rain drop size and velocity. However, studies modelling TKE with a high number of those factors are lacking. This study presents a new approach to model TKE. We used 20 biotic and abiotic factors to evaluate thresholds of those factors that can mitigate TKE and thus decrease soil erosion. Using these thresholds, an optimal set of biotic and abiotic factors was identified to minimize TKE. The model approach combined recursive feature elimination, random forest (RF) variable importance and classification and regression trees (CARTs). TKE was determined using 1405 splash cup measurements during five rainfall events in a subtropical Chinese tree plantation with five-year-old trees in 2013. Our results showed that leaf area, tree height, leaf area index and crown area are the most prominent vegetation traits to model TKE. To reduce TKE, the optimal set of biotic and abiotic factors was a leaf area lower than 6700mm2, a tree height lower than 290 cm combined with a crown base height lower than 60 cm, a leaf area index smaller than 1, more than 47 branches per tree and using single tree species neighbourhoods. Rainfall characteristics, such as amount and duration, further classified high or low TKE. These findings are important for the establishment of forest plantations that aim to minimize soil erosion in young succession stages using TKE modelling.
139

Étude du réservoir cellulaire du VIH-1 en fonction du traitement chez l’enfant infecté par transmission verticale

Canape, Jade 08 1900 (has links)
Contexte : Notre incapacité à guérir le VIH/SIDA vient au moins en partie du fait que le VIH établit et maintient des réservoirs cellulaires à l'abri des effets de la thérapie antirétrovirale combinée (cART) et de l'immunité de l'hôte. Alors que les composantes des réservoirs sont bien connues chez les adultes, la composition et l'évolution de ces réservoirs chez les enfants infectés verticalement sont moins bien comprises. Notre objectif était d'examiner les effets de l’âge de l’enfant au moment de l’initiation de la cART et de l'obtention d'une suppression virale soutenue (SVS) sur la taille et la nature du réservoir du VIH chez les enfants et les adolescents. Méthodes : À l'aide de la méthode HIV-Flow, la taille et la distribution des sous-types cellulaires du réservoir viral compétent pour la traduction ont été évaluées dans les cellules T CD4+ purifiées obtenues d'enfants et d'adolescents infectés verticalement (n=34) qui participaient à l'étude EPIC4 et qui ont été groupés selon l'âge (0-5, 5-10, 10-18 ans) et l’atteinte de la SVS. Résultats : Les différences de taille de réservoir entre les participants masculins et féminins ou entre les groupes d'âge n'étaient pas statistiquement significatives (p=0.5003, p=0.9410). Les cellules T CD4+ naïves étaient les principales contributrices au réservoir de cellules productrices de p24 dans tous les groupes d'âge, comparé aux cellules à mémoire centrale (CM), à mémoire effectrice (EM) et terminalement différenciées (TD) (p=0.001, p<0.0001, p<0.0001). La forte représentation des cellules T CD4+ naïves dans le pool total de cellules T CD4+ (⁓68% à >80%) peut expliquer cette contribution. Les cellules CM avaient tendance à présenter des fréquences plus élevées de cellules p24+ chez les adolescents par rapport aux groupes d'âge plus jeunes. Une corrélation négative a été observée entre la fréquence des cellules p24+ et la proportion de vie sous SVS (r=-0.3215, p=0.0318) ainsi que la proportion de vie sous cART efficace (r=-0.3197, p=0.0327). Conclusion : Contrairement aux adultes infectés par le VIH, le réservoir cellulaire hébergeant le VIH compétent pour la traduction chez les enfants et les adolescents infectés verticalement est principalement composé de cellules T CD4+ naïves, avec un profil de distribution se rapprochant progressivement avec l’âge de celui des adultes. Ces résultats éclairent et renforcent les orientations fondées sur des données probantes pour la prise en charge clinique et le traitement de l'infection verticale par le VIH. / Background: Our inability to cure HIV/AIDS stems at least in part from the fact that HIV establishes and maintains cellular reservoirs where it shelters from the effects of combination antiretroviral therapy (cART) and host immunity. Whereas reservoir components are well known in adults, the composition and evolution of these reservoirs in vertically infected children are incompletely understood. Our objective was to examine the effects of the timing of cART initiation and achievement of sustained viral suppression (SVS) on the size and nature of the HIV reservoir in children and adolescents. Methods: Using the HIV-Flow method, size and cell subset distribution of the translation competent viral reservoir were assessed in purified CD4+ T cells from vertically infected children and adolescents (n=34) with and without SVS, who were enrolled in the EPIC4 study and stratified according to age (0-5, 5-10, 10-18 years) and achievement/duration of SVS. Results: Differences in reservoir size between male and female participants or across age groups were not statistically significant (p=0.5003, p=0.9410). Naïve CD4+ T cells were the main contributor to the pool of p24-producing cells in all age groups as compared to central memory (CM), effector memory (EM), and terminally differentiated (TD) (p=0.001, p<0.0001, p<0.0001). The large representation of naïve CD4+ T cells in the total CD4+ T cells pool (⁓68% to >80%) can explain this contribution. CM cells tended to carry higher frequencies of p24+ cells in adolescents compared to younger age groups. A negative correlation was observed between the frequency of p24-positive cells and the proportion of life under SVS (r=-0.3215, p=0.0318) as well as the proportion of life under effective cART (r=-0.3197, p=0.0327). Conclusion: Unlike HIV-infected adults, the cellular reservoir harboring translation competent HIV in vertically infected children and adolescents is mostly comprised of naïve CD4+ T cells, with a distribution profile progressively transitioning to that of adults. These results inform and reinforce evidence-based guidance for the management of vertical HIV infection.
140

A Data-driven Approach to Identify Opportunities to Reduce Missing Doses

Lydick, Jaide E. 21 September 2016 (has links)
No description available.

Page generated in 0.0166 seconds