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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.
21

I skuggan av sociala medier : En studie om sociala mediers inverkan på unga kvinnors uppfattningar om ätstörningar / In the shadow of social media : A study on the impact of social media on young women’s perceptions of eating disorders

Iregren, Cassandra, Lind, Julia January 2020 (has links)
Bakgrund: Ätstörningar är vanligt hos unga kvinnor och etologin är okänd, biologiska och sociala faktorer kan påverka. Sociala medier används dagligen av unga kvinnor och innehållet kan framkalla negativa känslor vilka försämrar ätstörningen. Kvinnor med ätstörningar upplever ohälsa och lidande. För sjuksköterskan är det en utmaning att lindra lidande och sträva efter hälsa hos unga kvinnor med ätstörning. Syfte: Syftet var att belysa hur sociala medier inverkar på bloggande och vloggande unga kvinnors ätstörningar. Metod: I studien användes kvalitativ innehållsanalys för att analysera bloggar och vloggar producerade av unga kvinnor med ätstörning. Sju bloggkonton och två vloggkonton analyserades. Resultat: Sociala medier inverkar på unga kvinnors ätstörningar både positivt och negativt. Till stor del beror det på kvinnornas förmåga att identifiera triggers och att sluta följa konton som triggar. Sociala medier kan användas för att uttrycka känslor och tankar och vid ett sunt användande kan det stötta kvinnor till att förändra sitt beteende kring mat. Slutsats: Unga kvinnor med ätstörningar har ett stort behov av stöd och uppmuntran vilket de söker efter på sociala medier. Sjuksköterskan bör samtala med den unga kvinnan om sociala mediers inverkan på ätstörningsbeteendet. / Background: Eating disorders are common among young women and the ethology is unknown, biological and social factors can affect. Social media is used daily by young women and the content can evoke negative emotions which worsen the eating disorder. Women with eating disorders experience ill health and suffering, for the nurse it is a challenge to alleviate suffering and strive for health in young women with eating disorders. Purpose: The aim was to clarify social medias impact on blogging and vlogging young women´s eating disorders. Method: This study used qualitative content analysis to analyze blogs and vlogs produced by young women with eating disorder. Seven blog accounts and two vlog accounts were analyzed. Results: Social medias affects young women´s eating disorders both positively and negatively. This is largely due to women´s ability to identify triggers and to stop following accounts that trigger. Social media can be used to express feelings and thoughts and with healthy use it can support women to change their behavior around food. Conclusion: Young women with eating disorders have a great need for support and encouragement, which they are looking for on social media. The nurse should talk to the young woman about the impact of social media on eating disorder behavior.
22

Sphingosine kinase 1-interacting protein is a novel regulator of glucose-stimulated insulin secretion. / Sphingosine kinase 1-interacting protein はグルコース応答性インスリン分泌の新たな調節分子である。

Wang, Yu 24 July 2017 (has links)
京都大学 / 0048 / 新制・課程博士 / 博士(医学) / 甲第20616号 / 医博第4265号 / 新制||医||1023(附属図書館) / 京都大学大学院医学研究科医学専攻 / (主査)教授 長船 健二, 教授 渡邊 直樹, 教授 岩田 想 / 学位規則第4条第1項該当 / Doctor of Medical Science / Kyoto University / DFAM
23

Event-Triggered Attitude Stabilization of a Quadcopter

Almeida, Diogo January 2014 (has links)
There are many possible ways to perform the attitude control of a quadcopter and, recently, the subject of event-triggered control has become relevant in the scientic community. This thesis deals with the analysis and implementation of a saturating attitude controller for a quadcopter system, together with the derivation of an event-triggering rule to work with it. Two distinct rules are presented, one that ensures the stability of the closed loop system, the other, a linearised version that does not. The way those were derived consists in the use of a Lyapunov based approach. The stability of the system when under these rules was veried experimentally.
24

Triggering Relationships that Contextualize the Pathway for Student Success

Eckton, Darin R. 11 April 2012 (has links) (PDF)
America invests large amounts of money in K-12 education to develop its human capital. As such, K-12 student success is vital to the human capital development and future of America's children and adolescents. There is significant concern for the K-12 students who are predictably at risk of not graduating from high school (e.g., low-income, ethnic minority, and first generation college students) let alone qualifying for and enrolling in postsecondary education. Over the past four decades student success has primarily been explained by sociological research on status attainment as well as social capital and cultural capital. However, very little research addresses the relationship between this sociological research and motivation theory from the field of psychology. Specifically, student success research generally neglects describing how social capital and cultural capital become contextually and motivationally relevant for K-12 students. This study explored the pathway of success for students from the following backgrounds: low-income, first generation in college, active members of the Church of Jesus Christ of Latter-day Saints (LDS), Hispanic, graduated from a Utah high school in 2009 and who were admitted to Brigham Young University the same year as new freshmen. Case study methods were employed initially in phase one of the analysis using a grounded theory or emic paradigm, allowing data and patterns to emerge. In phase two of the analysis, using a post-positivist or etic paradigm data were contrasted with existing research. The findings revealed a new model that explains the conditions of student motivation. While the findings support existing research on the influences of social capital and cultural capital on student success, all students in this study experienced a triggering relationship that caused them to contextualize and assign value to various forms of capital in the past and present and leveraged them towards student success. This contextualization also served as a motivation for students to be successful and to pursue additional forms of capital to assist them on their pathway to success. The implications of this triggering relationship theory can assist parents, educators, and many others who facilitate the human capital development of children and adolescents.
25

Field Based Study of Gravel Liquefaction

Roy, Jashod 04 August 2022 (has links) (PDF)
Characterization and assessment of liquefaction potential of gravelly soil in a reliable cost-effective manner has always been a great challenge for the geotechnical engineers. The typical laboratory investigation techniques have proven to be ineffective for characterizing gravelly soil due to the cost and difficulty of extracting undisturbed sample from gravelly deposits. The traditional in-situ tests like SPT or CPT are not very suitable for gravelly soil because of interference with large size gravel particles which can artificially increase the penetration resistance. The Becker Penetration Test, well known for gravelly soil characterization, is cost-prohibitive for routine projects and is not available in most of the world. The Chinese dynamic cone penetration test (DPT) with a larger diameter probe compared to the SPT or CPT, can be economically performed with conventional drilling equipment. Besides the penetration testing, in-situ measurement of shear wave velocity (Vs) is another alternative of characterizing gravel liquefaction. Probabilistic liquefaction triggering curves were developed by performing both DPT and shear wave velocity test at the Chengdu Plain of China where massive gravel liquefaction took place during 2008 Wenchuan earthquake. These curves have significant uncertainty as they were developed from a single event database. As a part of this study, both DPT and Vs tests have been performed at various sites around the world where gravelly soil did or did not liquefy in various past earthquakes. These newly collected data have been added to the existing Chinese dataset to form a large database on gravel liquefaction case histories for both DPT and Vs. Based on this larger database, new magnitude dependent probabilistic liquefaction triggering procedures have been developed for both DPT and Vs. The larger database has significantly improved the triggering curves by reducing the spread and constraining the curves at both the higher and lower end. New Magnitude Scaling Factor (MSF) curves have been developed for both DPT and Vs which were found to be consistent with existing MSF curves. Further, an instructive comparison has been drawn between the performance of CPT and newly developed DPT triggering procedure the liquefaction potential of gravelly deposits CentrePort in Wellington. Results showed that both DPT and CPT performed reasonably well in liquefaction assessment of the gravelly fill. However, the CPT-based CRR profiles contain intermittent spikes due to the interaction with gravel particles whereas the DPT resistance appear to be relatively smooth. Similar comparison has been presented between the DPT and BPT in performing liquefaction assessment of gravelly soil at the Borah Peak sites in Idaho. It is found that both DPT and BPT successfully evaluate the liquefaction potential of the loose critical layers but the medium dense to dense layers are identified as non-liquefiable by the DPT whereas the same deposits are identified as liquefiable by the BPT. Lastly, an investigation has been carried out to observe the effect of hydraulic conductivity and in-situ drainage on the liquefaction triggering in gravelly soils based on field data along with a group of numerical analyses. It is found that the hydraulic conductivity of gravelly soil reduces with sand content which eventually may cause liquefaction during earthquake shaking. Low permeability cap layer may also impede the drainage path to generate excess pore pressure to trigger liquefaction in the gravelly strata.
26

Algebraic Trait for Structurally Balanced Property of Node and Its Applications in System Behaviors

Du, Wen (Electrical engineering researcher) 12 1900 (has links)
This thesis targets at providing an algebraic method to indicate network behaviors. Furthermore, for a signed-average consensus problem of the system behaviors, event-triggering signed-average algorithms are designed to reduce the communication overheads. In Chapter 1, the background is introduced, and the problem is formulated. In Chapter 2, notations and basics of graph theory are presented. It is known that the terminal value of the system state is determined by the initial state, left eigenvector and right eigenvector associated with zero eigenvalue of the Laplacian matrix. Since there is no mathematical expression of right eigenvector, in Chapter 3, mathematical expression of right eigenvector is given. In Chapter 4, algebraic trait for structurally balanced property of a node is proposed. In Chapter 5, a method for characterization of collective behaviors under directed signed networks is developed. In Chapter 6, dynamic event-triggering signed-average algorithms are proposed and proved for the purpose of relieving the communication burden between agents. Chapter 7 summarizes the thesis and gives future directions.
27

Anorexia Nervosa: Benefits of Recovery-Oriented Websites

Hersey, Sarah L. 27 March 2014 (has links)
No description available.
28

Liquefaction Triggering Model for Subduction Zone Earthquakes

Anbazhagan, Balakumar 14 September 2021 (has links)
Liquefaction is one of the major causes of ground failures during an earthquake. Recent evidence shows that the existing variants of the "simplified" liquefaction evaluation procedure lead to inaccurate results for megathrust earthquakes in subduction interfaces. To overcome this drawback and to achieve better prediction of liquefaction cases in subduction zones, this research intends to develop new empirical models that could be used for the prediction of liquefaction triggering in subduction zones. Towards this goal, new models for number of equivalent cycles (n_eq) and stress-reduction factor (r_d) have been proposed. The models are developed by regressing site response data obtained from 254 pairs of subduction ground motions and 77 representative soil profiles. To account for tectonic differences and magnitude scaling, separate models are developed for interface and intraslab earthquakes. The uncertainties involved in the proposed models are quantified through standard deviations of regression coefficients, event, site, and residual terms. The resulting models differ from other published models, especially the model for number of equivalent cycles. It was found that n_eq is greatly influenced by the fundamental site period. The model for r_d predicts higher values at shallow depths and lower values at deeper layers than other published models. Comparing the factors of safety against liquefaction with those from other existing models revealed that the use of models proposed in this research is more likely to reduce the "false positives" in liquefaction predictions, especially when design ground motion acceleration is high. / Master of Science / During earthquake shaking, loose saturated sands may lose strength and behave more like a liquid than a solid. This phenomenon is referred to liquefaction. Liquefaction has been responsible for infrastructure failure during past earthquakes, thus leading to major economic losses. This prompts the prediction and mitigation of potential liquefaction effects in a building site. However, the current state-of-the-practice for predicting liquefaction is inaccurate for large magnitude earthquakes in subduction zones. This provided the impetus for this research which focusses on developing new liquefaction evaluation models for large magnitude earthquakes. New models for number of equivalent cycles and stress reduction factor are developed by analyzing the representative ground motions and soil strata. These empirical parameters are central to the prediction of liquefaction triggering. Comparing the new models with the existing models revealed that the factor of safety against liquefaction estimated using new models are greater than those obtained using existing models for large magnitude earthquake scenario when the ground acceleration is high. This implies that using the existing models for predicting liquefaction in a site subjected to high values of ground acceleration from a subduction earthquake will lead to "false positives." Developed using a comprehensive dataset and robust regression techniques, the models developed in this research will lead to better predictions of liquefaction due to large subduction events.
29

Tailored Architectures of Ammonium Ionenes

Tamami, Mana 28 December 2009 (has links)
The synthesis and characterization of a variety of ammonium ionenes from water-soluble coatings to high-performance elastomers are discussed. Water-soluble random copolymer ionenes were synthesized using the Menshutkin reaction from 1,12-dibromododecane, N,N,Nâ ²,Nâ ²-tetramethyl-1,6-hexanediamine, and 1,12-bis(N,N-dimethylamino)dodecane. The absolute molecular weights were determined for the first time using a multiangle laser light scattering detector in aqueous size exclusion chromatography and the weight-average molecular weights of these ionenes were in the range of 17,000-20,000 g/mol. Charge density increased with increasing molar ratio of N,N,Nâ ²,Nâ ²-tetramethyl-1,6-hexanediamine and the glass transition temperature (Tg) increased from 69 °C to 90 °C as the charge density increased. Small angle x-ray scattering (SAXS) showed isotropic scattering patterns for these ionenes. A limited study on cytotoxicity of these ionenes showed no direct correlation between charge density and cell viability for human brain microvascular endothelial cell line. A series of low hard segment (HS) content, poly(propylene glycol) (PPG)-based ammonium ionenes were synthesized using a Menshutkin reaction from bromine end-capped PPG oligomers (prepared using acid-chloride reactions) and N,N,Nâ ²,Nâ ²-tetramethyl-1,6-hexanediamine. Matrix assisted laser desorption ionization-time of flight (MALDI-TOF) mass spectrometry, titration analyses, and ¹H NMR spectroscopy, confirmed the difunctionality of bromine end-capped PPG oligomers. Thermal analysis revealed Tg's of -60 °C, comparable to pure PPG, using differential scanning calorimetery (DSC), dynamic mechanical analysis (DMA) confirming microphase separation, and an onset of degradation (Td) at 240 °C. Synthesis of a series of random block copolymer ammonium ionenes with an aliphatic 1,12-dibromododecane as part of the hard segment (33 wt% HS) enhanced film formation and supported microphase separation property. The Td and Tg did not change compared to PPG-ionenes with lower HS content. DMA and tensile testing demonstrated the influence of soft segment (SS) molecular weight and hard segment (HS) content on the mechanical properties of segmented ammonium ionenes. DMA showed the onset of flow, ranging from 100-140 ºC for 1K and 2K g/mol PPG-based ionenes respectively. SAXS revealed a Bragg distance scaled with soft segment molecular weight and ranged from 6.6 to 23.4 nm for 1K to 4K g/mol PPG-based ionenes, respectively. An investigation of the salt-responsive solubility property of random block copolymer PPG-ionenes revealed a dependence on PPG molecular weight. The 1K g/mol PPG-based ionenes with a hydrophilic (HPL)/hydrophobic (HPB) value ranging from one to three showed solubility in both water and one wt% NaCl aqueous solutions. The 2K g/mol PPG-based ionenes containing HPL/HPB value of two to 15 showed cloudy dispersions in water and one wt% NaCl solutions. The 4K g/mol PPG-based ionenes possessed the salt-responsive character; 4K g/mol PPG-based ionenes with HPL/HPB values of one to 12 showed milky dispersions in water, suspended particles in one wt% NaCl solutions and film precipitation at a HPL/HPB molar ratio of 19. / Master of Science
30

Earthquake Sources and Hazard in northern Central America / Zonas y Amenaza Sísmica en el norte de America Central

Cáceres Calix, Diego José January 2003 (has links)
Northern Central America is a tectonically complex zone defined by its borders with Cocos and North America plates. The Middle America subduction zone and the strike-slip motion along the North America-Caribbean plate boundary, in that order, control most of its deformation. The interaction between the different elements of the studied area is evident from the high seismicity in the region, especially along plate boundaries. Also in the interior of the region, seismicity shows that deformation takes place, though in lesser degree. In a time window of 30 years, three earthquakes with moment magnitude larger than 7 struck northern Central America evincing the need to estimate the seismic hazard for the zone. To tackle the problem, we compiled a catalogue of hypocenters commencing in 1964, defined seismogenic sources and described the evolution of earthquake activity through a Poisson model. Probabilistic seismic hazard (PSH) calculations for the next 50 years were performed. The highest estimate of seismic hazard was obtained for the zone adjacent to the subduction zone. Because of the fundamental importance of demarcating seismogenic sources in the PSH analysis, i.e. defining the seismotectonic model, we extended the catalogue to cover 102 years for the whole northern Central America. We have studied the North America-Caribbean plate boundary in order to refine the fault representation. Different techniques were used, like that of body-waveform modeling, allowing us to limit the extent of depth of faulting to 20 km. The seismic moment tensor was used to estimate the deformation velocities on known tectonic structures, including those of the Honduras depression and borderland faults. Finally, we made use of the Coulomb stress criterion to determine the relation between earthquake occurrence and static stress changes following major earthquakes.

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