• Refine Query
  • Source
  • Publication year
  • to
  • Language
  • 396
  • 176
  • 67
  • 37
  • 29
  • 28
  • 24
  • 24
  • 15
  • 11
  • 8
  • 7
  • 6
  • 4
  • 4
  • Tagged with
  • 948
  • 113
  • 101
  • 85
  • 79
  • 64
  • 60
  • 60
  • 55
  • 55
  • 48
  • 47
  • 45
  • 44
  • 44
  • 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.
231

Midseason cold tolerance screening for the NSW rice improvement program

John Smith Unknown Date (has links)
The current rice varieties grown by Australian farmers are susceptible to low temperature events particularly during the reproductive stage of plant development. The best management practices of sowing within the recommended time period and maintaining deep water (20–25 cm) through the microspore development stage only offer limited protection. There is a need to develop more cold tolerant varieties and to do so requires the development of low-temperature screening capacity for the NSW rice breeding program. This study looked at the requirements of adapting a controlled-temperature glasshouse facility to enable screening for tolerance to low temperatures during the reproductive stage of rice development. The investigations were grouped into two areas; 1) the physical aspects of the low temperature facility including the location of plants within the facility and within the tubs used to grow the plants and whether these can influence the reliability of the screening and 2) the biological effects of nitrogen (N) concentration in the plant at panicle initiation (PI) and plant susceptibility to low temperatures, and whether growth stage of the plant relative to PI at the start of low temperature treatment influenced floret sterility. A series of nine experiments were conducted at the Deniliquin Agricultural Research and Advisory Station glasshouse facility using up to five rice varieties selected for their divergence in low-temperature tolerance. One other experiment was conducted in a different facility. The modified glasshouse facility in Deniliquin was effective in providing the targeted screening environment of 27°C day and 13°C night temperature regime. There was however a smaller than expected effect of the low temperature exposure in some of the experiments with sterility following low temperature ranging from 9.9% to 27.7%. There was also a higher than expected level of sterility in the controls (i.e. not exposed to low temperature) with sterility levels up to 58% recorded in one experiment. The causes of these overall effects are not known. Notwithstanding these overall effects there were a number of findings that are important for developing a reliable screening facility. The spatial arrangement of the plants within the low temperature facility effected the level of sterility highlighting the need for experimental design to consider spatial variation. The existence of edge effects was identified within the tubs used to maintain permanent water on the potted plants whereby the outer plants in the tubs were less damaged by the low-temperature treatment. The overall N level in the leaf tissue was low even at the equivalent rate of 250 kg N ha-1 and there was only a very modest and inconsistent response in N concentration at PI to N application rates ranging from 0 to 250 kg ha-1. However, the method of growing the plants in pots and of nitrogen fertiliser application did not alter the N concentration. The concentration was the same when N was added either, on the same day as permanent water application, or three days prior to permanent water application. Also restricting the direction of water movement through the pots and therefore the soil within the pots did not alter the amount of N in the plants at PI. The low plant N concentrations were consistent across two glasshouses in which soil from the same source was used suggesting a soil limitation. A soil test identified that the soil phosphorus (P) was at a level at which plants have responded to P application under field conditions, and the loamy texture of the soil had an associated low cation exchange capacity in comparison to medium to heavy clay soil types commonly associated with rice growing. These factors may have reduced the N retention and uptake and, in part, explain the low injury from the low temperature exposures. In the variety Millin, there was no significant effect of timing of the exposure on sterility until it commenced 12 to 15 days after PI. This is a significant finding for a breeding program that must expose lines of unknown phenological development. It means that even though there are small differences in the rates of development, there is no large effect of this on sterility. However, this response was not seen in the other varieties tested and thus requires further validation. It was difficult to induce repeatable levels of floret sterility in this series of experiments most likely due to the low N concentrations in part due to the properties of the soil used to grow the plants. This highlights the importance of standardising all cultural aspects in order to provide uniform and repeatable screening information. The spatial effects highlight importance of experimental design for effective exposure to low temperature treatments, incorporation of the capacity for spatial analysis in the statistical design, the use of standard variety checks for floret sterility after low temperature treatment, and the determination of N concentration in plant tissue prior to exposure.
232

An evaluation of the adult education initiative relative labor market training

Stenberg, Anders January 2003 (has links)
<p>This thesis consists of three papers which evaluate the effects of the Adult Education Initiative (AEI) in Sweden relative to the vocational part of Labor Market Training (LMT).</p><p>Paper [I] studies unemployment incidence and unemployment duration for participants in the AEI relative to LMT. When evaluating the relative program effects on duration, one needs to take into account both the problem of selection and the fact that the outcome variable is right hand censored. The method used is an instrumental variable adaptation of the symmetrically trimmed least squares estimator. A bivariate probit model is used in order to study unemployment incidence. The results indicate a beneficial effect of the AEI relative to LMT on unemployment incidence, but longer duration in unemployment among the AEI participants.</p><p>Paper [II] uses annual wage earnings in 1999 to compare the AEI and LMT for individuals that do not continue in education following program completion. Two separate estimation methods are used, the classical selection model and the method of matching on the propensity score. The results of both methods indicate negative effects of the AEI relative to LMT on wage earnings. The earnings effect of the AEI for individuals with a weak position in the labor market is particularly poor, implying that the official target to assist those individuals appear not to have succeeded.</p><p>Paper [III] employs data for those enrolled in 1997 as well as 1998 to study the annual wage earnings of 1999 and 2000 and data on attachment to branches of employment before and after program. Data on branches of employment indicate less mobility among the AEI participants. This is largely due to a stronger attachment to the public service sector. The analysis of wage earnings of the sample enrolled in 1997, indicate that the effects on wage earnings tended to be more advantageous for the AEI in 2000 rather than 1999, possibly implying a lag in the effects of the program.</p>
233

Polyrytmik : Bergson och erfarenhetens rytm

Linnros, David January 2008 (has links)
<p>Inspired by Kitaro Nishida’s concept of pure experience this thesis analyses Bergson’s concept of experience with the intention of showing how experience is related to duration and how this in turn destabilizes certain tendencies towards subjectivism that can be found in Bergson’s work. This is accomplished through a reading of Matter and memory, Creative Evolution and Introduction to metaphysics that tries to desintegrate both subject and object in favor of duration. The thesis arrives at describing the combination of duration and non-subjective and supra-individual experience as a polyrhythmic movement.</p>
234

Conditional co-occurrence probability acts like frequency in predicting fixation durations

Ong, James Kwan Yau, Kliegl, Reinhold January 2008 (has links)
The predictability of an upcoming word has been found to be a useful predictor in eye movement research, but is expensive to collect and subjective in nature. It would be desirable to have other predictors that are easier to collect and objective in nature if these predictors were capable of capturing the information stored in predictability. This paper contributes to this discussion by testing a possible predictor: conditional co-occurrence probability. This measure is a simple statistical representation of the relatedness of the current word to its context, based only on word co-occurrence patterns in data taken from the Internet. In the regression analyses, conditional co-occurrence probability acts like lexical frequency in predicting fixation durations, and its addition does not greatly improve the model fits. We conclude that readers do not seem to use the information contained within conditional co-occurrence probability during reading for meaning, and that similar simple measures of semantic relatedness are unlikely to be able to replace predictability as a predictor for fixation durations. Keywords: Co-occurrence probability, Cloze predictability, frequency, eye movement, fixation duration.
235

An evaluation of the adult education initiative relative labor market training

Stenberg, Anders January 2003 (has links)
This thesis consists of three papers which evaluate the effects of the Adult Education Initiative (AEI) in Sweden relative to the vocational part of Labor Market Training (LMT). Paper [I] studies unemployment incidence and unemployment duration for participants in the AEI relative to LMT. When evaluating the relative program effects on duration, one needs to take into account both the problem of selection and the fact that the outcome variable is right hand censored. The method used is an instrumental variable adaptation of the symmetrically trimmed least squares estimator. A bivariate probit model is used in order to study unemployment incidence. The results indicate a beneficial effect of the AEI relative to LMT on unemployment incidence, but longer duration in unemployment among the AEI participants. Paper [II] uses annual wage earnings in 1999 to compare the AEI and LMT for individuals that do not continue in education following program completion. Two separate estimation methods are used, the classical selection model and the method of matching on the propensity score. The results of both methods indicate negative effects of the AEI relative to LMT on wage earnings. The earnings effect of the AEI for individuals with a weak position in the labor market is particularly poor, implying that the official target to assist those individuals appear not to have succeeded. Paper [III] employs data for those enrolled in 1997 as well as 1998 to study the annual wage earnings of 1999 and 2000 and data on attachment to branches of employment before and after program. Data on branches of employment indicate less mobility among the AEI participants. This is largely due to a stronger attachment to the public service sector. The analysis of wage earnings of the sample enrolled in 1997, indicate that the effects on wage earnings tended to be more advantageous for the AEI in 2000 rather than 1999, possibly implying a lag in the effects of the program.
236

Polyrytmik : Bergson och erfarenhetens rytm

Linnros, David January 2008 (has links)
Inspired by Kitaro Nishida’s concept of pure experience this thesis analyses Bergson’s concept of experience with the intention of showing how experience is related to duration and how this in turn destabilizes certain tendencies towards subjectivism that can be found in Bergson’s work. This is accomplished through a reading of Matter and memory, Creative Evolution and Introduction to metaphysics that tries to desintegrate both subject and object in favor of duration. The thesis arrives at describing the combination of duration and non-subjective and supra-individual experience as a polyrhythmic movement.
237

Förstagångsmammor, Amning och deras upplevelse av Amningsstöd / Primiparous women, Breastfeeding and Breastfeeding Support

Cedermark, Ulrika January 2013 (has links)
Rekommendationerna är att spädbarn helammas i sex månader utan tillskott av annan föda. Trots att hälsoeffekterna för både mor och barn är välkända, har amningsprevalensen sjunkit i Sverige de sista åren. Syftet med denna studie var att undersöka om förstagångsmammor ammade så länge de tänkt sig, vilka orsaker som bidrog till att de slutade helamma respektive delamma och hur deras upplevelse av amningsstöd varit med speciellt fokus på barnhälsovården (BHV). En enkät skickades till 65 förstagångsmammor, vilket resulterade i 35 svar. Resultatet visade att knappt hälften av de mammor som svarade på enkäten hade avslutat sin amning tidigare än vad de tänkt sig. Hälften av de mammor som hade velat amma längre hade uppgett orsaker som kunde relateras till brist på stöd.  Resultatet visade även att många mammor söker stöd från det egna sociala nätverket och att stöd från mödrahälsovården (MHV) och förlossning/BB är viktigt för hur amningsstarten blir. BHV:s stöd är betydelsefullt när amningen ska etableras och upprätthållas vilket påverkar amningstidens längd. Det finns ett behov av fortsatt utbildning för vårdpersonal och amningsstödjare, gällande betydelsen av amning och bröstmjölk för att ge efterfrågat stöd till mammor som vill amma sina barn. / The health benefits of breastfeeding are well documented and guidelines for infant feeding have supported exclusive breastfeeding during the first 6 months. The breastfeeding prevalence has decreased in Sweden during the last ten years. The aim with this study was to find out if primaparous mothers could breastfeed as long as they had planned to do, reasons for stopping breastfeeding and how the mothers had perceived breastfeeding support, especially the support from the child health care. A questionnaire was sent out to 65 primiparous women and 35 mothers participated in the study. Almost half of the mothers had stopped breastfeeding earlier than they wanted to do. The result showed that many mothers looked for support in their own social network. The support from antenatal care, delivery and maternity ward, child health care was important in initiating breastfeeding as well as to maintain breastfeeding. There is a need of more education in breastfeeding and breast milk to health professionals and breastfeeding supporters to be able to support those mothers who want to breastfeed their babies.
238

Diabetes duration and health-related quality of life in individuals with onset of diabetes in the age group 15-34 years - a Swedish population-based study using EQ-5D

Sparring, Vibeke, Nystrom, Lennarth, Wahlström, Rolf, Jonsson, Pia Maria, Ostman, Jan, Burstrom, Kristina January 2013 (has links)
Background: Diabetes with onset in younger ages affects both length of life and health status due to debilitating and life-threatening long-term complications. In addition, episodes and fear of hypoglycaemia and of long-term consequences may have a substantial impact on health status. This study aims to describe and analyse health-related quality of life (HRQoL) in individuals with onset of diabetes at the age of 15-34 years and with a disease duration of 1, 8, 15 and 24 years compared with control individuals matched for age, sex and county of residence. Methods: Cross-sectional study of 839 individuals with diabetes and 1564 control individuals. Data on socioeconomic status and HRQoL using EQ-5D were collected by a postal questionnaire. Insulin treatment was self-reported by 94% of the patients, the majority most likely being type 1. Results: Individuals with diabetes reported lower HRQoL, with a significantly lower mean EQ VAS score in all cohorts of disease duration compared with control individuals for both men and women, and with a significantly lower EQ-5D(index) for women, but not for men, 15 years (0.76, p = 0.022) and 24 years (0.77, p = 0.016) after diagnosis compared with corresponding control individuals. Newly diagnosed individuals with diabetes reported significantly more problems compared with the control individuals in the dimension usual activities (women: 13.2% vs. 4.0%, p = 0.048; men: 11.4% vs. 4.1%, p = 0.033). In the other dimensions, differences between individuals with diabetes and control individuals were found 15 and 24 years after diagnosis: for women in the dimensions mobility, self-care, usual activities and pain/discomfort and for men in the dimension mobility. Multivariable regression analysis showed that diabetes duration, being a woman, having a lower education and not being married or cohabiting had a negative impact on HRQoL. Conclusions: Our study confirms the negative impact of diabetes on HRQoL and that the difference to control individuals increased by disease duration for women with diabetes. The small difference one year after diagnosis could imply a good management of diabetes care and a relatively quick adaptation. Our results also indicate that gender differences still exist in Sweden, despite modern diabetes treatment and management in Sweden.
239

Essays on Currency Crises

Karimi Zarkani, Mohammad 07 March 2012 (has links)
(None) Technical Summary of Thesis: The topic of my thesis is currency crisis. Currency crises have been a recurrent feature of the international economy from the invention of paper money. They are not confined to particular economies or specific region. They take place in developed, emerging, and developing countries and are spread all over the globe. Countries that experience currency crises face economic losses that can be huge and disruptive. However, the exacted toll is not only financial and economic, but also human, social, and political. It is clear that the currency crisis is a real threat to financial stability and economic prosperity. The main objective of this thesis is to analyze the determinants of currency crises for twenty OECD countries and South Africa from 1970 through 1998. It systematically examines the role of economic fundamentals and contagion in the origins of currency crises and empirically attempts to identify the channels through which the crises are being transmitted. It also examines the links between the incidence of currency crises and the choice of exchange rate regimes as well as the impact of capital market liberalization policies on the occurrence of currency crises. The first chapter identifies the episodes of currency crisis in our data set. Determining true crisis periods is a vital step in the empirical studies and has direct impact on the reliability of their estimations and the relevant policy implications. We define a period as a crisis episode when the Exchange Market Pressure (EMP) index, which consists of changes in exchange rates, reserves, and interest rates, exceeds a threshold. In order to minimize the concerns regarding the accuracy of identified crisis episodes, we apply extreme value theory, which is a more objective approach compared to other methods. In this chapter, we also select the reference country, which a country’s currency pressure index should be built around, in a more systematic way rather than by arbitrary choice or descriptive reasoning. The second chapter studies the probability of a currency exiting a tranquil state into a crisis state. There is an extensive literature on currency crises that empirically evaluate the roots and causes of the crises. Despite the interesting results of the current empirical literature, only very few of them account for the influence of time on the probability of crises. We use duration models that rigorously incorporate the time factor into the likelihood functions and allow us to investigate how the amount of time that a currency has already spent in the tranquil state affects the stability of a currency. Our findings show that high values of volatility of unemployment rates, inflation rates, contagion factors (which mostly work through trade channels), unemployment rates, real effective exchange rate, trade openness, and size of economy increases the hazard of a crisis. We make use of several robustness checks, including running our models on two different crisis episodes sets that are identified based on monthly and quarterly type spells. The third chapter examines the links between the incidence of currency crises and the choice of exchange rate regimes as well as the impact of capital market liberalization policies on the occurrence of currency crises. As in our previous paper, duration analysis is our methodology to study the probability of a currency crisis occurrence under different exchange rate regimes and capital mobility policies. The third chapter finds that there is a significant link between the choice of exchange rate regime and the incidence of currency crises in our sample. Nevertheless, the results are sensitive to the choice of the de facto exchange rate system. Moreover, in our sample, capital control policies appear to be helpful in preventing low duration currency crises. The results are robust to a wide variety of sample and models checks.
240

Computer Integrated Model to Estimate the Construction Cost and Duration of Building Projects at Their Feasibility Stage

Njeem, Wesam 26 November 2012 (has links)
Presently, owners are interested in evaluating the feasibility of investing in the construction of new building projects based on cost and time constraints. They need to therefore have an idea about the project construction costs, the time required to finish construction of a project in its conceptual phase, and about the implementation of feasibility study. Because due to associated risks, construction cost estimates and schedules are vital to any project. The research’s objective is to develop a methodology that can be used to create an integrated computer model that helps owners and designers generate construction cost estimates, and derive the baseline schedule for any proposed building project at its feasibility stage. All the relevant data used within the model is collected from the literature and is stored in comprehensive databases designed for this purpose. The data is based on 2011 RSMeans publications and consist of around 4,000 previously constructed projects. The model is developed in a Microsoft environment using Microsoft Excel 2007 and Microsoft Project 2007. This model uses deterministic and stochastic approaches to execute all necessary calculations for the conceptual cost estimate and baseline schedule. A deterministic approach relies on realistic data while a stochastic one relies on incorporating the uncertainty and risk available in calculating the cost and duration of any construction building project. The model is user friendly, flexible and executes all the necessary calculations quickly. The successful development of the model would help owners and investors identify the cost and baseline schedule of proposed projects at the early stages of the project life, so that they have an idea of the budget required for construction and the time needed to recover their investment.

Page generated in 0.3772 seconds