• Refine Query
  • Source
  • Publication year
  • to
  • Language
  • 404
  • 272
  • 132
  • 60
  • 59
  • 55
  • 11
  • 10
  • 8
  • 6
  • 6
  • 6
  • 4
  • 4
  • 3
  • Tagged with
  • 1202
  • 221
  • 128
  • 111
  • 104
  • 101
  • 93
  • 92
  • 84
  • 82
  • 80
  • 80
  • 66
  • 64
  • 64
  • 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

Attendre : de la disponibilité dans l'être / Waiting : of the availability in the being

Contador, Antonio 07 May 2015 (has links)
Rien de plus commun que d'admettre l'attente comme étant associée à un état de passivité ; le sujet qui attend est celui qui se garde de faire, son destin se dévoile au hasard de coups de dés plutôt qu'il n'est pris en main ; sa vie ne lui appartient pas, il n'en est pas véritablement le maître. Face à la mort sûre et à l'incertitude de l'avenir, anticiper, via l'effort d'aller au-devant au lieu d'attendre, semble aller de soi. Mais cette posture résolument active, dont l'énergie est puisée dans le souci d'une vie qui aura valu la peine d'être vécue, ne peut en conjurer le sort. Malgré tous les efforts, le constat est univoque : le temps demeure foncièrement irréversible, la mort irrévocable. Ainsi, anticiper la vie au lieu de l'attendre montre que le faire ne répond pas à toutes les questions, et qu'aller au-devant au lieu de rester quiet n'est qu'une manière de se donner l'illusion d'avoir les rênes en main.Attendre. De la disponibilité dans l'être vise à montrer que l'attente n'est pas le contraire de l'anticipation, ni la réponse face au constat d'échec de l'anticipation à en découdre avec le passage inexorable du temps. Qu'est-ce que l'attente ? Il y a, en fait, deux types d'attentes. D'une part, l'attente comme disponibilité expectante ; le sujet est en position de guet, il attend en anticipant ce qui n'est pas encore là et, en le faisant, il ne laisse pas venir le futur de façon imprévisible. Et d'autre part, l'attente pure et simple ; le sujet n'anticipe pas, il ne peut que laisser venir l'avenir, l'accueillir, aucun effort ne peut prédire son arrivée. En cela, elle est vision pure, dégagée de tout savoir et de toute élaboration ou activité consciente. Son apparition disparaissante laisse néanmoins présager sa mise en branle lente et inopinée dans les méandres de l'inconscient. En éclosant de la sorte, l'attente pure et simple n'en révèle pas moins des choses, des évidences qui informent le sujet attendant sur le sens de sa vie. / Nothing could be more common than to view waiting as a form of passivity; the one who waits is the one who refrains from doing, their fate is revealed by chance, on a throw of the dice, rather than taken in hand; their life does not belong to them, they are not truly the masters of their being. Confronted with a certain death and the uncertainty of the future, anticipating, via the effort of taking the initiative rather than waiting, seems self-evident. But this resolutely active position - for which energy is drawn from the desire to have a life worth living - cannot alter the course of destiny. In spite of all efforts made, the fact is unequivocal: time remains inherently irreversible, death irrevocable. Thus, anticipating life instead of waiting for it shows that doing does not answer all questions, and that taking the initiative instead of staying quiet is just a way to give oneself the illusion of taking control.Wainting. Of the availability in the being aims to show that waiting is not the opposite of anticipation, nor is it the answer when faced with the obvious failure of anticipation to battle with the unrelenting passing of time. What is waiting? There are in fact two forms of waiting. On the one hand, waiting as an expecting availability; while one waits, one is anticipating that which is not yet there, and in doing so, one does not let the future arrive unexpectedly. On the other hand, the pure and simple wait; here one does not anticipate, one can only let the future come, welcome it - no effort can predict its arrival. As such, it is a pure vision, rid of all knowledge, and of any conscious elaboration or activity. Its disappearing appearance heralds its slow and fortuitous setting in motion in the meanders of the unconscious. By blooming in such a way, the pure and simple wait reveals things, self-evident facts that inform the one waiting about the meaning of their lives.
22

Návrh a implementace vysoce dostupné aplikace v unixovém prostředí pro "call back system" / Design and implementation of a call back system utilizing JBoss and unix clustering

Vakula, Juraj January 2009 (has links)
The thesis is focused on use and implement High Availability cluster in the productive environment, where is needed to concentrate on business critical application. The main aim of this thesis is to create the environment for callback system, which consist from many software products, for example database, web, java and etc. A company has to consolidate every application in an flexible environment resistent to hardware failure, human error in order to be running 24/7.
23

Comparative Analysis of Energy-Based and Revenue-Based Availability Metrics of Wind Turbines

Ouchlou, El Mehdi January 2022 (has links)
Different key performance indicators are used to assess various aspects of a wind turbine (performance, reliability, financial aspects…). Availability metrics mainly, time-based and energy-based availability are the main indicators used to monitor and evaluate turbine’s availability performance today. However, due to significant growth of the share of energy sold into the electricity market as well as different selling structures, a new indicator has been established in order to assess availability performance in terms of revenues rather than time or energy.  This thesis compares energy and revenue-based availabilities of two turbines during 12 months of operational production. A methodology of calculation is suggested based on the International Electrotechnical Commission (IEC) information model for availability calculation. Time-based availability is calculated first, followed by energy-based, and finally revenue-based availability is derived from revenues as a result of combining energy production and electricity prices and revenue losses from energy losses and electricity prices. Availability metrics are calculated for three different scenarios, pure-market, mix of market and fixed price purchase agreement (PPA), and finally a PPA with a minimum monthly baseload to simulate the impact of volume risk. Results indicate a significant impact caused by the electricity price as well as the specifics of the selling agreement on revenue-based availability. Finding that in such cases, a significant divergence between energy and revenue-based indicators is possible. Limitations associated with the suggested methodology and case studies are presented and discussed.
24

Preventive Maintenance for a Multi-task System

Seward, Lori Welte 01 May 1998 (has links)
This research models the behavior of a multi-task system with respect to time. The type of multi-task system considered here is one in which not all system components are required to perform each task. Each component may, however, be used for more than one task. Also, it is possible that some of the components may be required for every task that the system performs. The components that are required for a subset of the tasks are considered to be intermittently demanded components and those components required for every task are continuously demanded components. This modeling approach assumes that the system is subject to a Modified Age Replacement Policy (MARP). With a MARP the intermittently demanded components are maintained during their idle periods and the continuously demanded components are replaced according to their age replacement times. A renewal theory approach is used to develop an availability expression for the multi-task system. Past research has focused on systems consisting of continuously demanded components and typically does not distinguish between elapsed clock time and elapsed operating time in the renewal density function expressions. This research recognizes that the operational age of an intermittently demanded component is different than the chronological age of the component. The renewal density function and availability measures are modeled using joint density functions defined on both clock time and operating time. The expressions are evaluated numerically using a multidimensional numerical integration routine. The results show logical behavior of the joint density functions used to define the availability measure. The availability measure also displays behavior consistent with the definition of a multi-task system. This model is an important development in the need for stochastic models of highly complex systems. The model is also a first step in defining performance measures for systems composed of both intermittently demanded components and continuously demanded components. / Ph. D.
25

Parametric availability studies for the global positioning system

Shaltot, Mohamed Mahrous January 1993 (has links)
No description available.
26

Trace Metals Mobility in Soils and Availability to Plants from a Long-Term Biosolids Amended Soil

Sukkariyah, Beshr 22 January 2004 (has links)
The long-term mobility and availability of trace metals has been cited as a potential hazard by critics of EPA 503 rule governing the land application of biosolids. The purpose of this research was to investigate the long-term effects of biosolids application on trace metals distribution and mobility. A single application of aerobically digested biosolids was applied to 1.5 x 2.3 m confined plots of a Davidson clay loam (clayey, kaolinitic, thermic, Rhodic Paleudult) in 1984 at 0, 42, 84, 126, 168, and 210 Mg/ha. The highest biosolids application supplied 4.5, 760, 43, and 620 kg ha-1 of Cd, Cu, Ni, and Zn, respectively. Radish (Raphanus sativus L.), lettuce (Lactuca sativa Var longifolia) and barley (Hordeum vulgare) were planted at the site. Soils were sampled to a depth of 0.9 m and sectioned into 5 cm increments after separating the Ap horizon. Total (EPA 3050B), available (Mehlich-I), sequential extraction, and dispersible clay analyses were performed on samples from the control, 126 Mg/ha and 210 Mg/ha treatments. Extractable (0.005 DTPA, 0.01 M CaCl2, and Mehlich-1) Cd, Cu, Ni, and Zn were measured on 15 cm-depth samples from each plot. Simple linear regression between plant metal concentration and biosolids-added trace metals were computed to determine uptake coefficients (UC) of crops for each metal as outlined by USEPA Part 503 Rule. Results indicated that more than 80% of the applied Cu and Zn are still found in the topsoil where biosolids were incorporated with slight enrichment down to 0.3 m. Biosolids application increased the concentration of trace metals in all the extracted fractions, with a large proportion of Zn and Cd present in the available forms. The major portion of Cu, Zn and Ni was associated with the metal-oxides fraction. Biosolids treatments had no significant effect on the yield of the crops. Plant uptake of trace metals differed among crops. Plant tissue metal concentrations increased with biosolids rate but were within the normal range for these crops. Trace metals concentration in plants generally correlated well with their concentrations extracted with 0.005 M DTPA, 0.01 M CaCl2 and Mehlich-1. Mehlich-1 gave the highest correlation coefficients for Cu and Zn and, therefore, was the most reliable in predicting their availability and uptake by the crops grown. Availability of trace metals as measured by Mehlich-I, DTPA, and CaCl2 extraction were higher in amended plots as compared to the control and increased linearly in response to biosolids addition. Metal concentration in the plants exhibited a plateau response in most cases. Several linear increases were observed in some cases in 2003 when the soil pH decreased below 5.5. The uptake coefficients values generated for the different crops were in agreement with the values set by the Part 503 Rule. / Ph. D.
27

Pharmacokinetics of a high-concentration formulation of buprenorphine (Simbadol®) in male dogs

Hansford, Jeremy Dustin 28 July 2021 (has links)
Objective: To describe the pharmacokinetics of buprenorphine in dogs following administration of a high-concentration formulation of buprenorphine. Study design: Prospective, randomized, crossover study. Animals: A total of six healthy male intact Beagle dogs, 9–13 months of age and weighing 10.3 ± 1.4 kg (mean ± standard deviation). Methods: Dogs were randomized to be administered buprenorphine (0.12 mg kg−1; Simbadol, 1.8 mg mL−1) via the intravenous (lateral saphenous) or subcutaneous (dorsal interscapular) route followed by the alternative route of administration after a 14 day interval. Blood was sampled before administration and at set times up to 72 hours after injection. Plasma buprenorphine concentration was measured using liquid chromatography–tandem mass spectrometry. Results: A 3-compartment model with zero or biphasic rapid and slow first order input in (intravenous or subcutaneous data, respectively) and first-order elimination from the central compartment best fitted the data. The rapid first order input accounted for 63% of the dosage absorption. Typical values (% interindividual variability) for the three compartment volumes were 900 (33), 2425 (not estimated) and 6360 (28) mL kg−1. The metabolic and two distribution clearances were 25.7 (21), 107.5 (74) and 5.7 (61) mL minute−1 kg−1. The absorption half-life for the fast absorption phase was 8.9 minutes with a 0.7 (103) minute delay. The absorption half-life for the slow absorption phase was 347 minutes with a 226 (42) minutes delay. Median (range) bioavailability calculated from noncompartmental analysis was 143 (80–239) %. Calculated terminal half-life was 963 minutes. Conclusions and clinical relevance: The high-concentration formulation of buprenorphine administered subcutaneously had a large volume of distribution and a rapid absorption phase followed by slower, delayed absorption. The high estimate of bioavailability should be interpreted with caution as values above 100% are most commonly related to experimental issues. / Master of Science / Opioids are ever-increasingly difficult to obtain for veterinary usage, although there is an FDA-approved and veterinary-specific formulation of buprenorphine (Simbadol) commercially available. Although only approved in cats, it has been used off-label in dogs due to its availability, despite minimal empirical evidence for its usage. Design: Six male beagle dogs were utilized in a randomized crossover study to evaluate the plasma concentrations of buprenorphine after intravenous and subcutaneous administration. Methodology: All dogs were anesthetized for central venous catheter placement. Following administration of the dosage (intravenous or subcutaneous), whole blood was sampled at set time points from one minute to three days. Blood was centrifuged and plasma removed for analysis of buprenorphine concentration, allowing pharmacokinetic modeling and creation of time-concentration curves. Results: Side effects were mild and associated with sedation. Appetite was transiently decreased in multiple dogs. A biphasic absorption model was determined from the subcutaneous data, with a rapid first phase accounting for the majority of absorption and a slower second phase occurring several hours later. Conclusions: The high-concentration formulation of buprenorphine administered subcutaneously resulted in a long terminal half-life and high estimate of bioavailability, although the latter should be interpreted cautiously. Relevance: The present study showed that the high-concentration formulation of buprenorphine is absorbed from subcutaneous administration in dogs with mild side effects. Further study is warranted on this formulation in dogs.
28

A Simulation Analysis of Bivariate Availability Models

Caruso, Elise M. 27 July 2000 (has links)
Equipment behavior is often discussed in terms of age and use. For example, an automobile is frequently referred to 3 years old with 30,000 miles. Bivariate failure modeling provides a framework for studying system behavior as a function of two variables. This is meaningful when studying the reliability/availability of systems and equipment. This thesis extends work done in the area of bivariate failure modeling. Four bivariate failure models are selected for analysis. The study includes exploration of bivariate random number generation. The random data is utilized in estimating the bivariate renewal function and bivariate availability function. The two measures provide insight on system behavior characterized by multiple variables. A method for generating bivariate failure and repair data is developed for each model. Of the four models, two represent correlated random variables; the other two, stochastic functionally dependent variables. Also, methods of estimating the bivariate renewals function and bivariate availability function are constructed. The bivariate failure and repair data from the four failure models is incorporated into the estimation processes to study various failure scenarios. / Master of Science
29

Dietary intake, energy availability and weight control practices of male apprentice jockeys residing at the SA Jockey Academy / Kathleen Theresa Krog

Krog, Kathleen Theresa January 2015 (has links)
INTRODUCTION Professional jockeys are considered elite sportsmen competing in a sport with certain weight restrictions. Horse racing is categorized as a “weight-making” sport where jockeys can benefit from attaining and/or maintaining a specific weight for competition. The minimum riding weight for professional jockeys and apprentice jockeys who are race riding is currently 52 kg. The lighter the jockey (i.e. the closer he can remain to the minimum weight of 52 kg) the more rides may be allocated to him (and the more money he will earn). This places a great deal of pressure on the jockey to maintain a low body weight, in order to attain rides. Unlike other weight category sports, horse riding does not have an “off season”, therefore jockeys are constantly pressured to maintain a minimal weight. Consequently this may result in unhealthy eating habits, dangerous weight control practices and compromised health. Research on the weight making practices of apprentice jockeys is scarce. In fact, there is currently no published data available on the South African apprentice jockey. The aim of this study was therefore to examine the dietary intake, energy availability and weight control practices of male apprentice jockeys residing at the South African Jockey Academy. METHODS Twenty one male flat jockey apprentices of different race groups, between the ages of 16 and 20 years were recruited to take part in this cross sectional observational study. Height, weight and body composition (body fat percentage and fat free mass) were measured. The apprentices completed a 59-item nutrition, health and lifestyle questionnaire including questions on weight control and weight making practices. Dietary intake was recorded with a 24-hour dietary recall on four non-consecutive days including a rest day, two training days, and a race day. On these days, exercise energy expenditure was also recorded with Actiheart© monitors with the aim to calculate energy availability. MAIN FINDINGS Total mean reported energy intake of the participants was 7088±2337kJ (35.5±12.5kcal/kg fat free mass [FFM]) and below the recommendations for athletes exercising several hours per day for most days of the week. The micronutrient intakes of the majority of these jockeys were also low (i.e. <67% of recommended intake). Mean calculated energy availability (EA) over two training days and one rest day was 27.1±16.7 kcal/kg FFM and regarded as low (i.e.<30kcal/kg/FFM). Furthermore, the majority of apprentices (88%) had a low EA on the training days. Ninety one percent of the jockeys reported the use of one or more weight control method including food avoidance (81%), restricting food intake and skipping meals (67%), exercising to sweat (48%) and using the sauna (43%). The top three reported side effects from making weight included thirst (80%), hunger (75%) and tiredness (75%). CONCLUSION In conclusion, the results of the present study showed that the majority of South African apprentice jockeys are practicing weight control methods, specifically restricting energy and food intake, to control their weight. This was supported by the mean low dietary energy intake and sub-optimal mean energy availability. These apprentice jockeys are therefore at risk for long-term health consequences including low bone mineral density. / MSc (Nutrition), North-West University, Potchefstroom Campus, 2015
30

Dietary intake, energy availability and weight control practices of male apprentice jockeys residing at the SA Jockey Academy / Kathleen Theresa Krog

Krog, Kathleen Theresa January 2015 (has links)
INTRODUCTION Professional jockeys are considered elite sportsmen competing in a sport with certain weight restrictions. Horse racing is categorized as a “weight-making” sport where jockeys can benefit from attaining and/or maintaining a specific weight for competition. The minimum riding weight for professional jockeys and apprentice jockeys who are race riding is currently 52 kg. The lighter the jockey (i.e. the closer he can remain to the minimum weight of 52 kg) the more rides may be allocated to him (and the more money he will earn). This places a great deal of pressure on the jockey to maintain a low body weight, in order to attain rides. Unlike other weight category sports, horse riding does not have an “off season”, therefore jockeys are constantly pressured to maintain a minimal weight. Consequently this may result in unhealthy eating habits, dangerous weight control practices and compromised health. Research on the weight making practices of apprentice jockeys is scarce. In fact, there is currently no published data available on the South African apprentice jockey. The aim of this study was therefore to examine the dietary intake, energy availability and weight control practices of male apprentice jockeys residing at the South African Jockey Academy. METHODS Twenty one male flat jockey apprentices of different race groups, between the ages of 16 and 20 years were recruited to take part in this cross sectional observational study. Height, weight and body composition (body fat percentage and fat free mass) were measured. The apprentices completed a 59-item nutrition, health and lifestyle questionnaire including questions on weight control and weight making practices. Dietary intake was recorded with a 24-hour dietary recall on four non-consecutive days including a rest day, two training days, and a race day. On these days, exercise energy expenditure was also recorded with Actiheart© monitors with the aim to calculate energy availability. MAIN FINDINGS Total mean reported energy intake of the participants was 7088±2337kJ (35.5±12.5kcal/kg fat free mass [FFM]) and below the recommendations for athletes exercising several hours per day for most days of the week. The micronutrient intakes of the majority of these jockeys were also low (i.e. <67% of recommended intake). Mean calculated energy availability (EA) over two training days and one rest day was 27.1±16.7 kcal/kg FFM and regarded as low (i.e.<30kcal/kg/FFM). Furthermore, the majority of apprentices (88%) had a low EA on the training days. Ninety one percent of the jockeys reported the use of one or more weight control method including food avoidance (81%), restricting food intake and skipping meals (67%), exercising to sweat (48%) and using the sauna (43%). The top three reported side effects from making weight included thirst (80%), hunger (75%) and tiredness (75%). CONCLUSION In conclusion, the results of the present study showed that the majority of South African apprentice jockeys are practicing weight control methods, specifically restricting energy and food intake, to control their weight. This was supported by the mean low dietary energy intake and sub-optimal mean energy availability. These apprentice jockeys are therefore at risk for long-term health consequences including low bone mineral density. / MSc (Nutrition), North-West University, Potchefstroom Campus, 2015

Page generated in 0.064 seconds