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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

The Effects of Lag Schedules and Multiple Alternatives on Response Resurgence

Bagwell, Ashley Frances 01 August 2015 (has links)
The mitigation of response resurgence is a topic which has garnered recent attention due to its importance in a clinical setting. The present study examined the mitigation of response resurgence in a human operant study using a computer program to teach multiple response alternatives using a Lag 3 schedule of reinforcement. Of the six undergraduate students who participated in this study, three came under the control of the programmed contingencies. All three of these participants demonstrated higher rates of resurgence in the component which simulated a single response alternative when compared to the component which simulated a multiple response alternative. Areas for future study are discussed.
22

Defasagem e letramento - uma experiência / Lag and lliteracy an experience

Danilo Antonio Amaral 13 December 2017 (has links)
Buscamos por meio da pesquisa-ação superar as defasagens encontradas pelos alunos ingressantes no primeiro ano do Ensino Médio, numa escola do interior de São Paulo na cidade de Ibaté, oriundos de diversas escolas do município, durante o ano letivo de 2017. Coletamos e analisamos alguns dados oriundos de avaliações externas Prova Brasil, SARESP e PISA a fim de ter um diagnóstico da situação educacional brasileira e a partir destes dados confrontamos com a realidade local. Percebemos que as defasagens são um grande entrave para o cumprimento dos currículos nas salas de aula e a partir disto buscamos meios para contorná-las dentro da nossa realidade. Este trabalho descreve uma experiência onde trabalhamos e buscamos desenvolver a leitura e a escrita em Matemática, a fim de sanar as limitações impostas pelas defasagens trazidas pelos nossos alunos. Apoiados em práticas que favorecessem o letramento matemático, pudemos a partir de um dado problema formulá-lo em uma linguagem adequada ao nível do desenvolvimento dos alunos, e empregando ferramentas matemáticas chegamos em resultados que puderam ser testados, interpretados e avaliados. Ao final do trabalho, verificamos uma melhora significativa quanto à resolução de problemas, como também em relação à interpretação e análise, onde os alunos puderam valer-se da sua individualidade para a resolução dos problemas propostos. / We seek through the action research to overcome the shortcomings encountered by incoming students in the first year of high school, in a school in the interior of São Paulo in the city of Ibaté, coming from several schools in the municipality during the school year 2017. We collect and analyze some data from external evaluations Prova Brasil, SARESP and PISA in order to have a diagnosis of the Brazilian educational situation and from these data we confront the local reality. We realize that the lags are a great obstacle for the fulfillment of the curricula in the classrooms and from this we look for means to circumvent them within our reality. This paper describes an experience where we work and seek to develop reading and writing in Mathematics, in order to remedy the limitations imposed by the lags brought by our students. Based on practices that favored mathematical literacy, we were able to formulate it in a language appropriate to the level of students development and using mathematical tools to arrive at results that could be tested, interpreted and evaluated. At the end of the study, we noticed a significant improvement in problem solving, as well as in relation to interpretation and analysis, where students were able to use their individuality to solve the problems proposed.
23

Multi-purpose methods for ionospheric radar measurements

Virtanen, I. (Ilkka) 23 November 2009 (has links)
Abstract From the very beginning of modern ionospheric science, different radar applications have been utilised in ionospheric measurements. The most sophisticated ionospheric radars are the incoherent scatter radars, which detect the extremely weak scattering of radio waves from thermal fluctuations in the ionospheric plasma. Besides the low signal level, the stochastic nature of the scattering process causes further complications to the measurements. The scattering produces a zero-mean random signal, whose autocorrelation function contains the information of the ionospheric plasma parameters. Incoherent scatter radars have been used for about half a century, but the demanding task of developing transmission modulation and data analysis is still in progress. In this thesis, a statistical inversion based method for removing range ambiguities from the autocorrelation functions, lag profile inversion, is applied to incoherent scatter radar data. The data have been recorded with the EISCAT incoherent scatter radars, located in Northern Fennoscandia. The method is first applied to standard EISCAT experiments, the results giving strong evidence that the method is applicable for the purpose, and it provides results of at least equal quality with the present standard methods. In subsequent studies, new radar modulation methods are developed, which may provide significant improvements to the present incoherent scatter radar experiments. All the methods have been tested with a real radar, and lag profile inversion has been successfully applied to the recorded data. The methods are also put to use in order to measure the predicted effects of artificial heating of the free electrons in the D-region of the ionosphere.
24

Assessment of rainfall and NDVI anomalies in semi-arid regions using distributed lag models

Zewdie, Worku, Csaplovics, E. 05 August 2019 (has links)
The semiarid regions of Ethiopia are exposed to anthropogenic and natural calamities. In this study, we assessed the relationship between Tropical Applications of Meteorology using Satellite data (TAMSAT) and MODIS Normalized Difference Vegetation Index (NDVI) data for the period 2000 to 2014 on decadal and annual basis using multivariate distributed lag (DL) models. Decadal growing season (June to September) values for kaftahumera were calculated from MODIS NDVI data. The growing season NDVI values are highly correlated with the precipitations during the whole study period. A lag of up to 30 days observed in most parts of our study region in which the rainfall has effects on vegetation growth after 40 days. The lag-time effects vary with the distribution of land use types and seasons. A lower correlation was observed in the woodland regions where significant deforestation occurred due to expansion of croplands. The loss in vegetation contributed to the low biomass production attributable to extended loss in vegetation cover.
25

Biomechanical Comparison of Three Methods for Internal Fixation of Femoral Neck Fractures in Dogs

Fisher, Stephen Cory 06 August 2011 (has links)
Research evaluating the surgical repair of femoral neck fractures in dogs is limited. This study evaluated the in vitro mechanical properties of canine femoral neck fractures stabilized with two medium Orthofix® Partially-threaded Kirschner Wires (Orthofix pins), a 2.7 mm cortical bone screw placed in lag fashion with anti-rotational Kirschner wire (K-wire), and three 1.1 mm divergent K-wires. This study compared the mean compressive pressure, compressive force and area of compression created by the insertion the Orthofix pins and a 2.7 mm cortical bone screw placed in lag fashion. Monotonic testing was used to quantify mechanical strength and pressure sensitive film was used to quantify compression. There was no significant difference in the stiffness or load to failure for the three repair methods evaluated. There was no significant difference in the compressive pressure, compressive force or area of compression in osteotomies stabilized with Orthofix pins and 2.7 mm bone screws.
26

Gamma-Ray Bursts: New Parameters For Measuring Energy Dependent Spectral Lag Times

Durst, Phillip Jefferson 11 December 2009 (has links)
A new method for measuring the hardness-intensity correlation (HIC) present in gamma-ray bursts (GRB) is developed. This method is used to measure the HIC for 100 single-peak gamma-ray bursts, 17 with known redshifts. The HIC is thus shown to be a consequence of energy-dependent lag times between hard and soft photons. Parameters derived from time profile fits using a modified double sigmoidal function are used to calculate a new set of lag time parameters for bursts, and these parameters are analyzed statistically to look for correlations with intrinsic GRB properties. This analysis shows that GRB red shift is related to lag times between hard and soft photons and that, to within 65% accuracy, GRB redshift can be predicted by the equation: z = 2.49 - 0.131(dpeak) - 0.473(MADS_dpeak)+ 0.143(decay_lag)
27

A Comparison of Methods for Addressing Lag Uncertainty in Cumulative Exposure-Response Analyses for Time-to-Event Data

Tan, Yubo 21 September 2017 (has links)
No description available.
28

The Effect of Letter Size on the Accommodative Response A Thesis

Landrum, Brian Thomas 22 July 2009 (has links)
No description available.
29

Newtons andra vagn

Juneby, Hans, Can, Mikael January 2015 (has links)
Ett problem för den grundläggande fysikundervisningen i skolan är att tyngdkraften ständigt stör experiment och demonstrationer, vilket gör det svårt för eleverna att förstå Newtons första och andra lag. Målet med projektet är att förbättra fysikundervisningen på högskolans bastermin. För att lösa problemet skapade vi en demonstrationsanläggning som effektivt demonstrerar inertialsystem och Newtons andra lag genom att köra ett specialkonstruerat tåg med konstant hastighet eller konstant acceleration. Eleverna har möjlighet att utföra tre olika experiment som styrs via en webbsida eller fjärrkontroll och analysera utgången genom grafer som ritas upp. Lösningen testades med mycket gott resultat. Slutsatsen är att man på ett effektivt sätt kan förbättra fysikundervisningen med hjälp av praktiska experiment som eleverna själva kan utföra. / A problem of basic physics education in schools is that gravitation constantly interferes with experiments and demonstrations, making it difficult for students to understand Newton's first and second laws. The goal of this project is to improve the physics education in colleges and universities. To solve the problem we created a demonstration system that effectively demonstrates an inertial reference frame and Newton's second law by driving a specially designed train with constant velocity or constant acceleration. Students are able to perform three different experiments which are controlled via a webpage or by remote control, and analyse the output through plotted graphs. After extensive testing, the train and experiments proved successful and we concluded that physics education can be effectively improved with the help of practical experiments that students themselves can perform.
30

Diskretionär förvaltning av premiepension : En granskning av förvaltningstjänster inom premiepension med fokus på investeringsprocessen / Discretionary Management of Premium Pension : A review of portfolio management services within premium pension focusing on the Investment process

Johansson, Emma, Mickelsson, Emma January 2011 (has links)
Bakgrund: Förvaltningstjänster inom premiepension har ökat i takt med införandet av det nya pensionssystemet. Marknaden för dessa aktörer har vuxit och det har riktats kritik mot förvaltningstjänsterna inom premiepension och dess förvaltare. De problem som förvaltningsföretagen påstås skapa riskerar att hota funktionaliteten och förtroendet i premiepensionssystemet. Aktörerna är ett relativt nytt fenomen i Sverige vilket gör att det inte finns tillgänglig information och statistik om förvaltarna och dess förvaltning. Lagar och finansiella teorier på området vägleder i hur förvaltarna bör och får agera, men anger inte hur förvaltningsföretagen arbetar i praktiken. Det är därför intressant att kartlägga förvaltarnas praktiska tillvägagångssätt angående förvaltning och investering för att därefter utvärdera det utifrån teorier och empirisk forskning med fokus på investeringsprocessen. Syfte: Syftet med studien är att kartlägga förvaltningstjänsterna inom premiepension med fokus på investeringsprocessen samt kritiskt granska den utifrån finansiell teori, empirisk forskning och rådande lagstiftning. Genomförande: För att besvara studiens syfte har dokumentstudier genomförts för att sammanställa studiens referensram gällande de lagar, finansiella teorier och empirisk forskning inom området. Därefter har det praktiska tillvägagångssättet inom diskretionär förvaltning av premiepension kartlagts genom intervjuer med nio av totalt nitton observerade förvaltningsföretag. Slutsats: Kartläggningen av förvaltningstjänsterna har påvisat att det finns olikheter i företagens praktiska tillvägagångssätt och processer vilket gör det svårt att jämföra företagen med varandra. Det finns förvaltningsföretag vars praktiska arbete stämmer överens med finansiella teorier, empirisk forskning och spelregler gällande investeringsprocessen. Överlag tyder dock studiens resultat på att förvaltningsföretagen har ett tillvägagångssätt som inte överensstämmer med dessa aspekter, vilket kan innebära utrymme för förbättring. / Background: As a result of the introduction of the new pension system, portfolio management services within the Premium pension have risen. The market for these actors has grown and the portfolio managers have been criticized to threat the functionality and the trust in the premium pension system. These actors are a relatively new phenomenon in Sweden, which means that there is no information and statistics available about the managers and their management processes. Laws and financial theories tell us how these managers should act, but they say nothing about how the managers work in practice. Therefore, it is interesting to identify the managers’ practical approach concerning the portfolio management and investment in order to evaluate the process by the means of the theories and empirical research. Aim: The aim of this study is to identify portfolio management services within premium pension focusing on investment process and critically examines it based on financial theory, empirical research and current laws. Completion: To fulfill the aim of this study, document studies have been implemented to summarize the frame of reference concerning laws, financial theories and empirical research. Subsequently the discretionary management of Premium pension is identified through interviews with nine companies of total nineteen companies observed. Conclusion: The identification of portfolio management services has proved that there are differences in companies' practical approaches and processes. This makes it difficult to compare the companies with each other. Some companies have a practical work that is consistent with financial theory, empirical research and the rules regarding the Investment process. Overall the results of the study suggest that portfolio management companies within premium pension have an approach that does not consist with these aspects, which can be improved.

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