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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.
271

Valid Inequalities for The 0-1 Mixed Knapsack Polytope with Upper Bounds

Cimren, Emrah 30 July 2010 (has links)
No description available.
272

Lifting body design and CFD analysis of a novel long range pentacopter, the TILT LR drone

Cagatay, Daniel, Yuan, Haoqian January 2016 (has links)
In the thesis, a lifting body has been designed aiming to generate lift force for the pentacopter, called TILT LR (Long Range), at higher velocities during flights to improve the aerodynamic performances. The configuration, which is used as the skeleton of the long range drone for up to 75 kilometers flights, is based upon a tilting system allowing the rotors to rotate around their own axis in both pitch and roll angles. This offers the possibility to the TILT LR flying withoutany vertical excess thrust at a proper angle of attack and velocity. This new drone can be directly applied to missions require long flight time or cover long distance, such as Search & Rescue(SAR), power lines and off-shore structures inspection, fire monitoring or surveillance. Several main CAD models have been created during the process of design and presented in the report together with the final design. For each model in the process, CFD simulations have been applied to observe the behaviors of the flows around the surfaces of the body during steady flights, followed by a brief analysis for further modification. A series of simulations with varying velocities and angle of attack have been performed for the final design, analyzing its performances under different air conditions. Flight envelope of the design has been presented also, together with some ideas of possible further studies on the pentacopter.
273

Konstruktion av lyftverktyg / Construction of a lifting accessory

Abdullahi Elmi, Summaya, Sahin, Elmas January 2021 (has links)
Detta projekts mål var att konstruera ett lyftverktyg som kan användas av Husmuttern, för att lyfta deras väggelement. Syftet med detta lyftverktyg är att underlätta byggprocessen i Husmutterns microfabrik och förutsätta säkra lyftningar av väggelementen. Väggelementen kan förekomma i olika varianter - ett med en panel, ett med ett fönster och ett med en dörr. Dessa varianter har olika tyngdpunkter och därmed var Husmuttern i behov av ett lyftverktyg som kan justeras utefter dessa olika varianter. Väggelementen förekommer även i två olika längder samt i två olika djup, vilket lyftverktyget också ska kunna justeras efter. Dessa justeringar ingår i kravspecifikationen. Lyftningen sker med både truck och travers, vilket verktyget ska vara anpassat till. Projektet utfördes enligt fyra faser; förstudier, planering, genomförande samt slutfas. I förstudierna studerades bl.a. tidigare förslag på lyftverktyg. Husmuttern hade en grundidé till ett lyftverktyg som projektgruppen skulle utgå ifrån i första hand. Som utgångspunkt för konceptgenereringen, gjordes analyser såsom funktionsanalys och QFD. Med brainstorming som metod, genererade gruppen fram flera koncept. Efter val av koncept med hjälp av diskussioner och beslutsmatriser, gjordes CAD-modell av lyftverktyget för att visualisera det färdiga förslaget. Förslaget som togs fram av gruppen på ett lyftverktyg, består av totalt fem komponenter - två U-liknande komponenter, två stödkomponenter och ett lyftrör. Gruppens förslag är en utveckling på Husmutterns grundidé. Justering efter tyngdpunkt sker med hjälp av stödkomponenten på U-komponenten. Lyftröret har olika öglor för de olika längderna på väggelementet. Justering efter djup görs genom att ha två olika U-komponenter, som har olika djup. / The goal of this project was to construct a lifting accessory that can be used by Husmuttern, to lift their wall elements. The purpose of this lifting accessory is to facilitate the construction process in Husmuttern:s microfactory and safe lifts of the wall elements. The wall elements come in different types - one with a panel, one with a window and one with a door. These different types of wall elements vary in their centre of gravity, thus Husmuttern was in need of a lifting accessory that can adjust to these varieties. The wall elements come also in two different lengths and two different depths, which the lifting accessory also should be able to adjust to. These adjustments are included in the requirements specification. The lifting is done with both a forklift truck and a traverser, which the lifting accessory should be adapted to. The project was done according to four phases; feasibility studies, planning, executing and finish. In the phase of feasibility studies, the project group studied inter alia previous suggestion on a lifting accessory. Husmuttern did have an idea of a lifting accessory, that the project group would start with first and foremost. As a starting point for the generation of concepts, analyses such as functions analysis and QFD was conducted. With brainstorming as a method, several concepts were genererated within the group. After choosing an eventual concept by means of discussions and decision matrices, a CAD-model was done of the lifting accessory in order to visualize the suggestion. The group’s suggestion of a lifting accessory consists of five components in total - two U-components, two support-components and one pipe. The group’s suggestion is a development of Husmuttern:s idea. Adjustment to the centre of gravity, is done by adjusting the support-component on the U-component. The pipe has different coils for the different lengths of the wall-element. Adjustment to the different depths is done by having two different U-components, which have different depths.
274

The effect of an endurance and weight training program on plasma total cholesterol and high-density lipoprotein-cholesterol

Webb, Kelsie R. January 1987 (has links)
Research has reported that increased levels of plasma TC are directly related, while low levels of plasma HDL-C are inversely related, to coronary heart disease. Regular physical exercise has been suggested as a method for reducing plasma TC and increasing plasma HDL-C. Thirty-one healthy, sedentary women (ages 18-30) were studied to determine the effects of a jogging, weight training, or a combined jogging and weight training program on plasma total cholesterol, high-density lipoproteins, body composition. Experimental subjects were randomly assigned to the treatment conditions. The subjects trained three days a week for nine weeks. The R group ran for 30 minutes a session at 75% predicted maximum HR. The W group trained with weights utilizing exercises to strengthen all major muscle groups for one hour at 60% one repetition maximum the first 3 weeks and 75% one repetition maximum weeks 4 - 9. The RW group ran for 25 minutes a session at 75% predicted maximum HR, then lifted weights using the leg-strengthening exercises for 30 minutes, similar to the W group. Preceding and following the treatment period, plasma TC, HDL-C, body weight, and percent body fat was assessed for all four groups. Plasma TC was not significantly altered, although a downward trend was observed for all three treatment groups. Plasma HDL-C did not change over the treatment period for any group. The plasma TC/HDL-C ratio changed significantly among groups over the treatment period, with the R group decreasing their ratio from 3.5 to 2.9 (p < .05). No changes were noted In percent body fat, fat-free mass, or body weight for any of the groups. The Pearson product-moment correlations performed between the changes in blood lipids and the changes in body composition found no significant relationships. The results of this study indicate that an exercise program consisting of endurance training for 30 minutes, 3 times per week, or weight training for one hour, 3 times per week, or a combination aerobic/weight training program 3 times per week is not adequate to significantly improve plasma TC or HDL-C in young females over a nine week period. However, significant improvements may be made in the plasma TC/HDL-C ratio which may decrease the risk for CHD. / Master of Science
275

The effects of oral arginine supplementation on growth hormone, arginine, and somatomedin levels during energy restriction in male weight lifters

Fild, Deborah S. 24 November 2009 (has links)
Twelve male weight lifters were used to study the effect of oral arginine consumption on growth hormone (hGH) , arginine (Arg), and somatomedin (IGF-1) concentrations. Subjects were randomly assigned to treatment or placebo groups. Following a week of controlled exercise and diet, fasted subjects took either an acute dose of arginine hydrochloride or casein (placebo), at 0.1 g/kg BW. Blood samples were drawn every 15 min, for 90 min after ingestion. All samples were analyzed for hGH and Arg, and IGF-1 was measured in the baseline sample. Subjects then underwent 10 days of caloric restriction, consuming a liquid diet of 22 kcal/kg BW/d. Subjects took either arginine or casein supplements in two doses of 0.1 g/kg BW twice daily, for a total dose of 0.2 g/kg BW/d. The weight lifting protocol remained unchanged. On day 17, subjects were again tested for the acute response to a single dose of 0.1 g/kg BW supplement (arginine or placebo) over 90 min. Blood was collected and analyzed as before. No change in hGH and Arg occurred 90 min after consumption of the arginine supplement, regardless of dietary condition. However, arginine supplementation caused overall higher hGH and Arg levels (2.64 ng/ml and 0.87 mmol/l) compared to placebo (1.36 ng/ml and 0.71 mmol/l) during caloric restriction. IGF-1 did not change in either group under either diet. Thus, oral arginine supplementation at 0.1 g/kg BW did not produce a rise in hGH or Arg after 90 min, and did not affect overall hGH status, as measured by IGF-1, during energy restriction and supplementation. / Master of Science
276

Moving and handling children after death: an inductive thematic analysis of the factors that influence decision-making by children's hospice staff

Tatterton, Michael J., Honour, A., Kirby, L., Billington, D. 02 October 2021 (has links)
No / Hospices for children and adolescents in the United Kingdom provide care to the bodies of deceased children, in specially-designed chilled bedrooms called ‘cool rooms’. In an effort to develop resources to support hospice practitioners to provide this specialist area of care, the study aimed to identify the factors that influence decision-making when moving and handling children’s bodies after death in a hospice cool bedroom. An internet-based survey was sent to all practitioners employed by one children’s hospice. A total of 94.9% of eligible staff responded (n=56). An inductive approach to thematic analysis was undertaken, using a six-phase methodological framework. Three core themes were identified that inform practitioners’ perception of appropriateness of moving and handling decisions: care of the body, stages of care, and method of handling. The complexity of decision-making and variation in practice was identified. Practitioners relied on both analytical and initiative decision-making, with more experienced practitioners using an intuitive approach. Evidence-based policy and training influence the perception of appropriateness, and the decisions and behaviour of practitioners. The development of a policy and education framework would support practitioners in caring for children’s bodies after death, standardising expectations and measures of competence in relation to moving and handling tasks.
277

Regressão não-paramétrica com erros correlacionados via ondaletas. / Non-parametric regression with correlated errors using wavelets

Porto, Rogério de Faria 03 October 2008 (has links)
Nesta tese, são obtidas taxas de convergência a zero, do risco de estimação obtido com regressão não-paramétrica via ondaletas, quando há erros correlacionados. Quatro métodos de regressão não-paramétrica via ondaletas, com delineamento desigualmente espaçado são estudados na presença de erros correlacionados, oriundos de processos estocásticos. São apresentadas condições sobre os erros e adaptações aos procedimentos necessárias à obtenção de taxas de convergência quase minimax, para os estimadores. Sempre que possível são obtidas taxas de convergência para os estimadores no domínio da função, sob condições bastante gerais a respeito da função a ser estimada, do delineamento e da correlação dos erros. Mediante estudos de simulação, são avaliados os comportamentos de alguns métodos propostos quando aplicados a amostras finitas. Em geral sugere-se usar um dos procedimentos estudados, porém aplicando-se limiares por níveis. Como a estimação da variância dos coecientes de detalhes pode ser problemática em alguns casos, também se propõe um procedimento iterativo semi-paramétrico geral para métodos que utilizam ondaletas, na presença de erros em séries temporais. / In this thesis, rates of convergence to zero are obtained for the estimation risk, for non-parametric regression using wavelets, when the errors are correlated. Four non-parametric regression methods using wavelets, with un-equally spaced design are studied in the presence of correlated errors, that come from stochastic processes. Conditions on the errors and adaptations to the procedures are presented, so that the estimators achieve quasi-minimax rates of convergence. Whenever is possible, rates of convergence are obtained for the estimators in the domain of the function, under mild conditions on the function to be estimated, on the design and on the error correlation. Through simulation studies, the behavior of some of the proposed methods is evaluated, when used on finite samples. Generally, it is suggested to use one of the studied methods, however applying thresholds by level. Since the estimation of the detail coecients can be dicult in some cases, it is also proposed a general semi-parametric iterative procedure, for wavelet methods in the presence of time-series errors.
278

Regressão não-paramétrica com erros correlacionados via ondaletas. / Non-parametric regression with correlated errors using wavelets

Rogério de Faria Porto 03 October 2008 (has links)
Nesta tese, são obtidas taxas de convergência a zero, do risco de estimação obtido com regressão não-paramétrica via ondaletas, quando há erros correlacionados. Quatro métodos de regressão não-paramétrica via ondaletas, com delineamento desigualmente espaçado são estudados na presença de erros correlacionados, oriundos de processos estocásticos. São apresentadas condições sobre os erros e adaptações aos procedimentos necessárias à obtenção de taxas de convergência quase minimax, para os estimadores. Sempre que possível são obtidas taxas de convergência para os estimadores no domínio da função, sob condições bastante gerais a respeito da função a ser estimada, do delineamento e da correlação dos erros. Mediante estudos de simulação, são avaliados os comportamentos de alguns métodos propostos quando aplicados a amostras finitas. Em geral sugere-se usar um dos procedimentos estudados, porém aplicando-se limiares por níveis. Como a estimação da variância dos coecientes de detalhes pode ser problemática em alguns casos, também se propõe um procedimento iterativo semi-paramétrico geral para métodos que utilizam ondaletas, na presença de erros em séries temporais. / In this thesis, rates of convergence to zero are obtained for the estimation risk, for non-parametric regression using wavelets, when the errors are correlated. Four non-parametric regression methods using wavelets, with un-equally spaced design are studied in the presence of correlated errors, that come from stochastic processes. Conditions on the errors and adaptations to the procedures are presented, so that the estimators achieve quasi-minimax rates of convergence. Whenever is possible, rates of convergence are obtained for the estimators in the domain of the function, under mild conditions on the function to be estimated, on the design and on the error correlation. Through simulation studies, the behavior of some of the proposed methods is evaluated, when used on finite samples. Generally, it is suggested to use one of the studied methods, however applying thresholds by level. Since the estimation of the detail coecients can be dicult in some cases, it is also proposed a general semi-parametric iterative procedure, for wavelet methods in the presence of time-series errors.
279

Automating a labour performance measurement and risk assessment: an evaluation of methods for a computer vision based system

Van Blommestein, Donald Lloyd 04 1900 (has links)
Thesis (MScEng) Stellenbosch University, 2014 / ENGLISH ABSTRACT: This thesis brings together productivity and risk assessments through innovative design, development and evaluation of a unique system for retrieving and analysing data. In the past, although the link between them is well-documented, these assessments have largely been dealt with as separate antagonist entities. A broad evaluation of the existing traditional and technological support systems has been conducted to identify suitable methodologies along with a common technological platform for automation. The methodologies selected for the productivity and risk assessments were; work sampling and the revised NIOSH lifting equation respectively. The automation of these procedures is facilitated through computer vision and the use of a range imaging Kinect™ camera. The standalone C++ application integrates two tracking approaches to extract real-time positional data on the worker and the work-piece. The OpenNI and OpenCV libraries are used to perform skeletal tracking and image recognition respectively. The skeletal tracker returns positional data on specific joints of the worker, while the image recognition component, a SURF implementation, is used to identify and track a specific work-piece within the capture frame. These tracking techniques are computationally expensive. In order to enable real time execution of the program, Nvidia’s CUDA toolkit and threading building blocks have been applied to reduce the processing time. The performance measurement system is a continuous sampling derivative of work sampling. The speed of the worker’s hand movements and proximity to the work-piece are used to classify the worker in one of four possible states; busy, static, idle, or out of frame. In addition to the worker based performance measures, data relating to work-pieces are also calculated. These include the number of work-pieces processed by a specific worker, along with the average and variations in the processing times. The risk assessment is an automated approach of the revised NIOSH lifting equation. The system calculates when a worker makes and/or breaks contact with the work-piece and uses the joint locations from the skeletal tracker to calculate the variables used in the determination of the multipliers and ultimately the recommended weight limit and lifting index. The final calculation indicates whether the worker is at risk of developing a musculoskeletal disorder. Additionally the information provided on each of the multipliers highlights which elements of the lifting task contribute the most to the risk. The user-interface design ensures that the system is easy to use. The interface also displays the results of the study enabling analysts to assess worker performance at any time in real time. The automated system therefore enables analysts to respond rapidly to rectify problems. The system also reduces the complexity of performing studies and it eliminates human errors. The time and costs required to perform the studies are reduced and the system can become a permanent fixture on factory floors. The development of the automated system opens the door for further development of the system to ultimately enable more detailed assessments of productivity and risk. / AFRIKAANSE OPSOMMING: Produktiwiteit en risiko evaluerings word in hierdie tesis saam hanteer deur die innoverende ontwerp, ontwikkeling en evaluering van 'n unieke stelsel vir die meting en ontleding van data. Alhoewel die skakel tussen hulle goed gedokumenteer is, word hierdie evaluering as afsonderlike antagonistiese entiteite hanteer. 'n Breë studie van die bestaande tradisionele en tegnologiese ondersteuningstelsels is gedoen om toepaslike metodes te identifiseer, om 'n gemeenskaplike tegnologiese platform vir outomatisering daar te stel. Die metodes wat gekies is vir die produktiwiteit en risiko bepalings is onderskeidelik werk monsterneming en die hersiende NIOSH opheffing vergelyking. Die outomatisering van hierdie prosedures word gefasiliteer deur middel van rekenaar visie en die gebruik van 'n Kinect™ 3D kamera. Die selfstandige C++ program integreer ‘n dubbelvolgings benadering om in reële tyd posisionele data van die werker en die werk-stuk te kry. Die OpenNI en OpenCV biblioteke word onderskeidelik gebruik om skeletale volging en beeld erkenning uit te voer. Die skeletale volger bepaal posisionele data van spesifieke gewrigte van die werker, terwyl die beeld erkenning komponent, 'n SURF implementering gebruik om 'n spesifieke werk-stuk binne die opname raam te identifiseer en te volg. Hierdie volgings tegnieke is berekenings intensief. Om werklike tyd uitvoering van die program te verseker, is Nvidia se CUDA gereedskapstel en liggewig boublokke geimplementeer. Die produktiwiteit meting-stelsel is 'n aaneenlopende monsterneming benadering van werk monsterneming. Die spoed van die werker se handbewegings en nabyheid aan die werkstuk word gebruik om die werker te klassifiseer as in een van vier moontlike toestande; besig, staties, onaktief of buite die raam. Benewens die werker gebaseerde metings, word daar ook data oor werkstukke bereken. Dit sluit in die aantal werkstukke verwerk deur 'n spesifieke werker, sowel as die gemiddelde en variasie in verwerkings tye. Die risiko-berekening is 'n outomatiese benadering van die hersiende NIOSH opheffing vergelyking. Die stelsel bereken wanneer die werker kontak maak en/of breek met die werkstuk en maak gebruik van die gewrigsposisies wat die skeletale volger aandui om die veranderlikes wat in die vermenigvuldigers gebruik word te bepaal. Die vermenigvuldigers word gebruik om die aanbevole maksimum gewig en die opheffing indeks te bereken. Die opheffing indeks dui aan of daar ‘n risiko vir die werker is om muskuloskeletale versteuring te ontwikkel. Benewens dui die vermenigvuldigers aan watter elemente die grootste bydra tot die risiko van die opheffingstaak maak. Die gebruiker-koppelvlak-ontwerp verseker dat die stelsel maklik is om te gebruik. Die koppelvlak vertoon ook die resultate van die studie sodat ontleders op enige tyd werker prestasie kan evalueer in reële tyd. Die outomatiese stelsel stel dus ontleders in staat om vinnig te reageer sodat probleme reggestel kan word. Die stelsel verminder ook die kompleksiteit vir die uitvoering van studies en dit elimineer menslike foute. Die tyd en koste vereis om die studie te doen, word verminder en die stelsel kan ‘n permanente instelling op fabriekvloere geword. Die ontwikkeling van die outomatiese stelsel maak die deur oop vir verdere ontwikkeling van die stelsel om uiteindelik daartoe te lei dat meer gedetailleerde evaluering van produktiwiteit en risiko bepaal kan word.
280

Srovnání implementací diskrétní waveletové transformace v Javě a C/C++ / Comparison of discrete wavelet transform implementations in C and Java

Talavašek, Kamil January 2008 (has links)
This thesis deals with discrete wavelet transform of a two dimensional discrete signal using the CDF9/7 wavelet. It contains theoretical principles of discrete wavelet transformation, a description of the convolution and Lifting calculation principle, characteristics of the CDF9/7 wavelet, the possibilities of processing a two dimensional input signal and boundary handling. Both principles (convolution, Lifting) of the calculation of two dimensional discrete wavelet transformation have been implemented within the thesis using the CDF9/7 wavelet in the C++ and Java programming languages. Four applications have been created that way which have been described in detail and then compared with one another especially in light of the calculation speed of discrete wavelet transformation. Finally an analysis of the acquired results and an evaluation of the whole thesis has been performed.

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