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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.
131

Investigation of Possible Novel Peptide Inhibitors to BAG-1 Based On Peptidyl-Biomimetics

Brunn, Jonathan 07 December 2012 (has links)
In this Master’s Thesis Research the results can be summarized from two major tasks: (1) In our first task, we utilized our two protein system (BAG-1 and HSP 70) as part of beta testing of a computational software 1 that can take three dimensional x-ray crystallography information about protein complexes and predict the strength of atom –atom interactions between amino-acid residues Open Contact predicts binding hotspots that can be used to identify short amino acid chains or peptides that mimic that particular binding segment of the larger protein. These peptides are called pepidyl-biomimetics. The peptide can potentially act as an antagonist drug by binding to the hotspot on protein A before protein B of the A-B complex can form. Two potential peptide candidates were identified. In particular, a helical peptide was discovered that demonstrated a variety of different types of atom-atom interactions. (2) Our second task is to experimentally test the helical peptide for its ability to block the binding that occurs between the 70-kilodalton Heat Shock Protein (HSP-70) and the Bcl-2 Associated Athanogene (BAG-1) Protein. As reviewed here, the binding between HSP-70 and BAG-1 elicits a cascade of cellular events that maintain high cancer growth rates and a greatly increased resistance to chemotherapy. In addition, BAG-1 has been implicated in a number of onco-signal pathways, as reviewed here, and its inhibition alone is believed to act as an agent against cancer cell growth
132

Studie hur Woolpowers sovsäckslakan    påverkar isoleringen och   temperaturgraderingen av olika sovsäckar och hur de förhåller sig till en   konkurrent

Evander, Manne January 2019 (has links)
Med olika ISO-standarder och artiklar som bakgrund har   Woolpowers sovsäckslakan Sleeping Bag   Liner:s värmeresistans (isolerande förmåga) undersökts på tre olika   sovsäckar. Med hjälp av en docka med termologiska egenskaper har värden för   värmeresistansen tagits fram. Vidare överfördes värdet till en skala för   temperatur, i vilken komfort-, övergångs- och extremtemperatur erhölls.   Samtliga sovsäckar uppvisade en tydlig ökning i värmeresistansen när   sovsäckslakanet användes, vilket i förlängningen betydde att   temperaturgränserna också förändrades. Ett konkurrerande sovsäckslakan blev även testat. Dels   för att undersöka hur Woolpower står sig mot en av de övriga producenterna på   marknaden, dels för att kritiskt granska den information som förmedlas till   konsumenter av produkten samt för att diskutera huruvida dem graderingarna   som används idag kan förändras för att ge konsumenten tydligare information   om produkten. I jämförelsen mellan Woolpower och konkurrenten visade det sig   att Woolpowers hade en högre ökning av värmeresistansen i samtliga sovsäckar.   Detta öppnar upp för en frågeställning, då konkurrenten påstår   på sin produkt att den potentiellt ska öka sovsäckstemperaturen med upp till   15°C. Enligt föreliggande undersökningsmätningar är lakanet inte i närheten   av detta. Om Woolpowers lakan hade testats med den metod som konkurrenten   använt sig av, hade då resultatet visat på någonting annat? Detta öppnar upp   för ett ifrågasättande av den gradering som används på sovsäckslakan idag och   möjligheterna att införa en separat standard för befintliga och framtida   produkter. / With the   help from different standards and articles, tests have been run on a sleeping   bag liner from the company Woolpower, on three different sleeping bags with   different grading for the temperature. Using a thermal manikin, a value for   the total insulation (heat resistance) was defined, and that value was   translated into different scales for temperature, including comfort-,   transition- and extreme temperature limits. All the sleeping bags show a   clear improvement of the insulation value when using the Woolpower liner,   which means that the grading for the temperature limits also changes. A liner   from a competitor company was also evaluated, not only to compare how well   Woolpower´s liner holds up on the market and how well the temperature that   the competing liner put on their product holds up to the value from this   test, but also to open up for a discussion how the grading of the products   used today can be changed to better fit its purpose. In this comparison   between Woolpower and the other company’s liner, Woolpower have a higher   insulation value in all the sleeping bags. These   questions the reliability of the marking on the liners that are used today,   since the results demonstrated in this study are far from what the product   claims. If Woolpowers liner was tested with the same method, would the result   be any different? It opens the possibility to introduce a separate standard   to determine the heat insulation potentials of the liner so that all the   producers follow the same guidelines. / <p>Betyg 2019-07-12</p>
133

När hjärtat slutar slå - En kvalitativ intervjustudie om prehospital luftvägshantering vid hjärtstopp

Modin, Erik, Nadia, Ameur January 2019 (has links)
Bakgrund Ambulanssjuksköterskans hantering av luftvägen och ventilering vid hjärtstopp är av stor vikt för att en patient ska kunna återupplivas. Många hjälpmedel finns för att underlätta detta arbete, men prehospitalt finns det åtskilliga faktorer att ta hänsyn till som inte existerar på sjukhus och som kan inverka på ambulanssjuksköterskans val av metod för ventilering. Syfte Att undersöka vilka faktorer som påverkar ambulanssjuksköterskans val av metod för ventilering vid hjärtstopp. Metod En kvalitativ design användes med semistrukturerade intervjuer. Åtta intervjuer med specialistsjuksköterskor inom intensivvård och ambulanssjukvård genomfördes. Kvalitativ innehållsanalys användes för att analysera materialet.  Resultat Dataanalysen resulterade i fyra kategorier med tillhörande underkategorier. I kategorin Tiden prioriterades snabb ventilering för patienten samtidigt som avståndet till sjukhus också påverkade val av metod. Patienten och dennes förutsättningar är en kategori där bakomliggande orsaker till hjärtstoppet, patientens anatomiska förutsättningar samt om hjärtstoppet avslutades på plats eller inte påverkade ambulanssjuksköterskans metodval. Tredje kategorin var resurser som påverkade metodvalet genom att antalet enheter på plats och deras kompetens och erfarenhet hade en inverkan på metodval. Den fjärde kategorin användarvänlighet handlar om miljöfaktorer som påverkade metodvalet samt transport av patienten där avancerade metoder föredrogs för att underlätta förflyttningen. Slutsats Många av dessa faktorer är sådant som inte är något problem på sjukhus men som ambulanssjuksköterskan behöver vara medveten om. Vissa av faktorerna kan avhjälpas av verksamheten med ökad utbildning och modern utrustning men andra faktorer är sådant som ambulanssjuksköterskan behöver vara redo för att hantera. / Background Airway management is of great importance to the resuscitation in patients with cardiac arrest. There are a lot of tools to alleviate this task, but there are several factors to consider in out-of-hospital cardiac arrest, that doesn't exists within the hospital walls, that may influence the ambulance nurse method for managing the ventilation. Aim To study witch factors that influence the ambulance nurse choice of method to ventilate an out-of-hospital cardiac arrest. Methods A qualitative design was used with semi-structured interviews. Eight interviews were conducted with nursing specialists within intensive- and prehospital care. Qualitative content analysis was used to analyze the collected data. Results Data analysis resulted in four categories with associated under-categories. In the category Time distance to hospital had an effect on the choice of ventilation and fast ventilation was prioritized. The Patient was a category where the cause of the cardiac arrest, the patient anatomy and if the resuscitation was terminated on the spot or not was identified to have an impact on the method of airway management. The third category was Resources that influenced the airway approach was the amount of units on the scene and their competence and experience. The fourth category was ease-of-use where environment had an influence on airway management as well as the transportation of the patient. Conclusion Even though these factors often are a none-issue in the hospital it's vital to the ambulance nurse to be aware of these. Some factors can be alleviated by the agency with increased education and modern equipment but other factors are just something the ambulance nurse needs to be aware of and able to handle.
134

Metodologia para automação de inspeção visual de bolsas para coleta de sangue / Methodology to automation visual inspection for blood bags

Adorni, Cássio Avelino 28 July 2008 (has links)
As bolsas para coleta de sangue necessitam cuidados técnicos que assegurem sua esterilidade biológica durante o processo de fabricação até a entrega do produto final. As bolsas para coleta de sangue não devem conter qualquer tipo de resíduo, para que o seu uso ou conteúdo não seja comprometido causando diversos transtornos. É preciso eliminar o risco de contaminação; no entanto muitas empresas fazem a inspeção de bolsas para coleta de sangue visualmente, a olho nu, por funcionários treinados no uso de equipamento simples, o qual não pode garantir que todas as bolsas estejam livres de resíduos, por depender do fator humano. Para assegurar a esterilização das bolsas comercializadas, este trabalho propõe uma metodologia para automação de um sistema de visão computacional baseado em conjunto de técnica de extração de características de imagens e reconhecimento de padrões para detectar resíduos em imagens de bolsas para coleta de sangue durante o processo de fabricação, e assim, melhorar a qualidade das bolsas comercializadas. Os resíduos encontrados nas imagens capturadas se apresentam como componentes de alta freqüência. A metodologia proposta utiliza a Transformada Wavelet (Wavelet de Haar) em dois níveis de decomposição, como filtro passa - alta para destacar as altas freqüências, e assim detectar a existência de resíduos nas imagens capturadas. Os resultados obtidos com a inspeção visual manual realizada em bolsas para coleta de sangue, mostram que existem resultados divergentes na análise de uma mesma bolsa, o que reforça a necessidade de automatização dessa tarefa para que sejam obtidos resultados mais uniformes com padrões definidos, e dessa maneira melhorar a qualidade das bolsas comercializadas para coleta de sangue. / The blood bags require technician attention to assure its biological sterility in the process of manufacture and in the final product. The blood bags must not contain any type of waste, so that its use or content is not compromised causing various disorders; it is necessary to eliminate any contamination risk; however many companies perform a visually inspection of the blood bags, by naked eye, by trained employees in the use of a simple equipment, which cannot guarantee that all the bags are residue-free because depending on the human factor. The residues showed on the pictures were characterized as high frequency components. So the proposed methodology applies two levels decomposition of Haar´s Wavelet as high pass filter to evidence high frequencies, and to evidence the residues at the pictures and to evidence the existence of residues on the captured pictures. To assure the sterilization of the commercialized blood bags, this work propose a methodology of an automated computational system based in a group of techniques of image characteristics extraction and recognition patterns to detect residues in blood bag images in the process of manufacture, in order to improve the quality of the commercialized blood bags.This technique is used as high-pass filter, to detach the high frequencies, using a Haar-wavelet in two decomposition levels. The results obtained with the manual visual inspection indicate that were found divergent results in the analysis of the same blood bag, which reinforces the necessity of the automation of this task in order to obtain more uniform results with defined standards.
135

Design and Characterization of a Human Exposure Chamber and Inversion Episodes in Salt Lake City, Utah in January/February of 2009

Kuprov, Roman Yuri 10 August 2009 (has links)
Research on health effects of particulate matter (PM) has been a very active area in the last two decades. One plausible mechanism by which exposure to PM affects human health includes modification of autonomic endothelium function. Decreased endothelium activity causes heightened risks of cardiovascular disease. A human exposure chamber designed to conduct experiments to quantify diminished function of endothelium from short term exposure to PM is described. The chamber consists of two stages for containment and pre-treatment of PM and exposure of human subjects. Concentrations of CO, CO2, NO, NO2, O3, and PM2.5, are monitored and controlled in the exposure room. The PM used in the human exposure experiments was characterized chemically and morphologically. During January and February of 2009, chemical analysis of PM2.5 was done during inversion periods in Salt Lake City, UT. An Ambient Ion Monitor (AIM) was deployed to measure the concentrations of anions in both particulate and gas phases. The chemical data provided by AIM was complemented by measurements by the Department of Air Quality that included PM10, PM2.5, O3, NO, NO2, NH3 and CO. The goal of the study was to determine whether ammonia or nitric acid is the limiting reagent in formation of PM during inversions. Nitric acid is the limiting reagent. Concentrations of ammonia are an order of magnitude higher than nitric acid.
136

Real-time Hand Gesture Detection and Recognition for Human Computer Interaction

Dardas, Nasser Hasan Abdel-Qader 08 November 2012 (has links)
This thesis focuses on bare hand gesture recognition by proposing a new architecture to solve the problem of real-time vision-based hand detection, tracking, and gesture recognition for interaction with an application via hand gestures. The first stage of our system allows detecting and tracking a bare hand in a cluttered background using face subtraction, skin detection and contour comparison. The second stage allows recognizing hand gestures using bag-of-features and multi-class Support Vector Machine (SVM) algorithms. Finally, a grammar has been developed to generate gesture commands for application control. Our hand gesture recognition system consists of two steps: offline training and online testing. In the training stage, after extracting the keypoints for every training image using the Scale Invariance Feature Transform (SIFT), a vector quantization technique will map keypoints from every training image into a unified dimensional histogram vector (bag-of-words) after K-means clustering. This histogram is treated as an input vector for a multi-class SVM to build the classifier. In the testing stage, for every frame captured from a webcam, the hand is detected using my algorithm. Then, the keypoints are extracted for every small image that contains the detected hand posture and fed into the cluster model to map them into a bag-of-words vector, which is fed into the multi-class SVM classifier to recognize the hand gesture. Another hand gesture recognition system was proposed using Principle Components Analysis (PCA). The most eigenvectors and weights of training images are determined. In the testing stage, the hand posture is detected for every frame using my algorithm. Then, the small image that contains the detected hand is projected onto the most eigenvectors of training images to form its test weights. Finally, the minimum Euclidean distance is determined among the test weights and the training weights of each training image to recognize the hand gesture. Two application of gesture-based interaction with a 3D gaming virtual environment were implemented. The exertion videogame makes use of a stationary bicycle as one of the main inputs for game playing. The user can control and direct left-right movement and shooting actions in the game by a set of hand gesture commands, while in the second game, the user can control and direct a helicopter over the city by a set of hand gesture commands.
137

Development and simulation of hard real-time switched-ethernet avionics data network

Chen, Tao 08 1900 (has links)
The computer and microelectronics technologies are developing very quickly nowadays. In the mean time, the modern integrated avionics systems are burgeoning unceasingly. The modern integrated modular architecture more and more requires the low-latency and reliable communication databus with the high bandwidth. The traditional avionics databus technology, such as ARINC429, can not provide enough high speed and size for data communication, and it is a problem to achieve transmission mission successfully between the advanced avionic devices with the sufficient bandwidth. AFDX(Avionics Full Duplex Switched Ethernet) is a good solution for this problem, which is the high-speed full duplex switched avionic databus, on the basis of the Ethernet technology. AFDX can not only avoid Ethernet conflicts and collisions, but also increase transmission rate with a lower weigh of the databus. AFDX is now adopted by A380,B787 aircraft successfully. The avionics data must be delivered punctualy and reliablely, so it is very essential to validate the real-time performance of AFDX during the design process. The simulation is a good method to acquire the network performance, but it only happends in some given set of scenarios, and it is impossible to consider every case. So a sophisticatd network performance method for the worst-case scenario with the pessimistic upper bound requires to be deduced. The avionic design engineers have launched many researches in the AFDX simulation and methods study. That is the goal that this thesis is aimming for. The development of this project can been planned in the following two steps. In the first step, a communication platform plans to be implemented to simulate the AFDX network in two versions – the RTAI realtime framework and Linux user space framework. Ultimately, these frameworks need to be integrated into net-ASS, which is an integrated simulation and assessment platform in the cranfield’s lab.The second step deduces an effective method to evaluate network performance, including three bounds(delay,backlog and output flow), based on the NC. It is called Network Calculus. It is an internet theory keeping the network system in determistic way. It is also used in communication queue management. This mathematics method is planed to be verified with simulation results from the AFDX simuation communication platform, in order to assure its validity and applicability. All in all, the project aims to assess the performance of different network topologies in different avionic architectures, through the simulation and the mathematical assessment. The technologies used in this thesis benefit to find problems and faults in the beginning stage of the avionics architecture design in the industrial project, especially, in terms of guarantee the lossless service in avionics databus.
138

Geo-spatial Object Detection Using Local Descriptors

Aytekin, Caglar 01 August 2011 (has links) (PDF)
There is an increasing trend towards object detection from aerial and satellite images. Most of the widely used object detection algorithms are based on local features. In such an approach, first, the local features are detected and described in an image, then a representation of the images are formed using these local features for supervised learning and these representations are used during classification . In this thesis, Harris and SIFT algorithms are used as local feature detector and SIFT approach is used as a local feature descriptor. Using these tools, Bag of Visual Words algorithm is examined in order to represent an image by the help of histograms of visual words. Finally, SVM classifier is trained by using positive and negative samples from a training set. In addition to the classical bag of visual words approach, two novel extensions are also proposed. As the first case, the visual words are weighted proportional to their importance of belonging to positive samples. The important features are basically the features occurring more in the object and less in the background. Secondly, a principal component analysis after forming the histograms is processed in order to remove the undesired redundancy and noise in the data, reduce the dimension of the data to yield better classifying performance. Based on the test results, it could be argued that the proposed approach is capable to detecting a number of geo-spatial objects, such as airplane or ships, for a reasonable performance.
139

Determinants of the supply-side fragmentation of maize storage in the North Western Free State production area / Mathys Johannes Nicolaas van der Merwe.

Van der Merwe, Mathys Johannes Nicolaas January 2012 (has links)
For decades commercial silos in South Africa was the only option in which maize could be delivered and sold. After deregulation in the late 1990s commercial silo owners came to face the challenge of alternative storage solutions and loss of market share. The reasons are determined for a shift from commercial storage to on-farm storage. The extent to which on-farm storage will change the current maize storage industry is discussed. The study commences by describing the birth and rapid growth of maize production in South Africa. Soon after maize became a major role-player in the export industry, it was characterised by regulation. The rationale why the market was regulated and how it influenced grain storage is explained. The deregulation process and the objectives of the new Marketing of Agricultural Products Act, No. 47 of 1996, are paraphrased. In the deregulated market, current and future, maize prices are determined by supply and demand. Incentives for storage emerged and cheaper substitutes with various other advantages began to propose alternative storage solutions to farmers. These concurrences of circumstances then lead to fragmentation of grain storage in South Africa. As a relatively young free market, the maize value chain is described to illustrate the position of each role-player in relation to the silo owner. The new price determination factors, price movement rationale and the use of market instruments are subsequently explained. Naturally, a critical assessment of the main different storage solutions available for farmers, are investigated next. Fragmentation is defined and discussed in terms of market equilibrium. A comparison is drawn between the South African and the Australian as well as the US maize storage industry. The empirical research was conducted on two sample groups of farmers in the Free State. The first group is farmers that already make use of an on-farm storage facility. The second group is farmers that annually produce more than 5000 tons of maize and currently do not make use of an on-farm storage facility. Seven important reasons for an on-farm storage facility are determined in the literature study as well as a qualitative study that preceded the quantitative study. Respondents are asked to rank the reasons in order of, in their opinion, importance. A generalized profile of a respondent in each sample group was compiled. Hereafter the outcome of the reasons ranked by both sample groups is discussed. It appeared that Flexible Marketing Option was the most important reason for farmers that already make use of on-farm storage. Farmers did not indicate that Handling and Storage costs are the most important reason why they would invest in an on-farm storage facility. Correlations are drawn between groups and the significance of differences is determined. It is concluded that on-farm storage is sustainable and there will be an increase of the phenomenon over the next three years. Recommendations are given for commercial silo owners to regain market share. Costs analyses and effective cost management along with the promotion that marketing options are just as flexible within commercial silos, as it is outside, are some of the recommendations made. / Thesis (MBA)--North-West University, Potchefstroom Campus, 2013.
140

Determinants of the supply-side fragmentation of maize storage in the North Western Free State production area / Mathys Johannes Nicolaas van der Merwe.

Van der Merwe, Mathys Johannes Nicolaas January 2012 (has links)
For decades commercial silos in South Africa was the only option in which maize could be delivered and sold. After deregulation in the late 1990s commercial silo owners came to face the challenge of alternative storage solutions and loss of market share. The reasons are determined for a shift from commercial storage to on-farm storage. The extent to which on-farm storage will change the current maize storage industry is discussed. The study commences by describing the birth and rapid growth of maize production in South Africa. Soon after maize became a major role-player in the export industry, it was characterised by regulation. The rationale why the market was regulated and how it influenced grain storage is explained. The deregulation process and the objectives of the new Marketing of Agricultural Products Act, No. 47 of 1996, are paraphrased. In the deregulated market, current and future, maize prices are determined by supply and demand. Incentives for storage emerged and cheaper substitutes with various other advantages began to propose alternative storage solutions to farmers. These concurrences of circumstances then lead to fragmentation of grain storage in South Africa. As a relatively young free market, the maize value chain is described to illustrate the position of each role-player in relation to the silo owner. The new price determination factors, price movement rationale and the use of market instruments are subsequently explained. Naturally, a critical assessment of the main different storage solutions available for farmers, are investigated next. Fragmentation is defined and discussed in terms of market equilibrium. A comparison is drawn between the South African and the Australian as well as the US maize storage industry. The empirical research was conducted on two sample groups of farmers in the Free State. The first group is farmers that already make use of an on-farm storage facility. The second group is farmers that annually produce more than 5000 tons of maize and currently do not make use of an on-farm storage facility. Seven important reasons for an on-farm storage facility are determined in the literature study as well as a qualitative study that preceded the quantitative study. Respondents are asked to rank the reasons in order of, in their opinion, importance. A generalized profile of a respondent in each sample group was compiled. Hereafter the outcome of the reasons ranked by both sample groups is discussed. It appeared that Flexible Marketing Option was the most important reason for farmers that already make use of on-farm storage. Farmers did not indicate that Handling and Storage costs are the most important reason why they would invest in an on-farm storage facility. Correlations are drawn between groups and the significance of differences is determined. It is concluded that on-farm storage is sustainable and there will be an increase of the phenomenon over the next three years. Recommendations are given for commercial silo owners to regain market share. Costs analyses and effective cost management along with the promotion that marketing options are just as flexible within commercial silos, as it is outside, are some of the recommendations made. / Thesis (MBA)--North-West University, Potchefstroom Campus, 2013.

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