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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.
751

Developing and applying precision animal farming tools for poultry behavior monitoring

Li, Guoming 30 April 2021 (has links)
Appropriate measurement of broiler behaviors is critical to optimize broiler production efficiency and improve precision management strategies. However, performance of different precision tools on measuring broiler behaviors of interest remains unclear. This dissertation systematically developed and evaluated radio frequency identification (RFID) system, image processing, and deep learning for automatically detecting and analyzing broiler behaviors. Then different behaviors (i.e., feeding, drinking, stretching, restricted feeding) of broilers under representative management practices were measured using the developed precision tools. The broilers were Ross 708 in weeks 4-8. The major findings show that the RFID system achieved high performance (over 90% accuracy) for continuously tracking feeding and drinking behaviors of individual broilers, after they were customized and modified, such as tag sensitivity test, power adjustment, radio wave shielding, and assessment of interference by add-ons. The image processing algorithms combined with a machine learning model were customized and adjusted based on the experimental conditions and finally achieved 85% sensitivity, specificity, and accuracy for detecting bird number at feeder and at drinkers. After adjusting labeling method and hyperparameter tuning, the faster region-based convolutional neural network (faster R-CNN) had over 86% precision, recall, specificity, and accuracy for detecting broiler stretching behaviors. In comprehensive algorithms, the faster R-CNN showed over 92% precision, recall, and F1 score for detecting feeder, eating birds, and birds around feeder. The bird trackers had a 3.2% error rate to track individual birds around feeder. The support vector machine behavior classifier achieved over 92% performance for classifying walking birds. Image processing model was also developed to detect birds that were restricted to feeder access. Broilers had different behavior responses to different sessions of a day, bird ages, environments, diets, and allocated resources. Reducing stocking density, increasing feeder space, and applying poultry-specific light spectrum and intensity were beneficial for birds to perform behaviors, such as feeding, drinking, and stretching, while using the antibiotics-free diet reduced bird feeding time. In conclusion, the developed tools are useful tools for automated broiler behavior monitoring and the measured behavior responses provide insights into precision management of welfare-oriented broiler production.
752

RADIO-FREQUENCY ABLATION IN A RECONSTRUCTED REALISTIC HEPATIC TISSUE

PANDEY, AJIT K. 02 September 2003 (has links)
No description available.
753

RADIO FREQUENCY CONTROLLED STIMULATION OF INTRACELLULAR GOLD OR SILVER NANOPARTICLE CONJUGATES FOR USE AS POTENTIAL SENSORS OR MODULATORS OF BIOLOGICAL FUNCTION

Murdock, Richard Craig 29 June 2010 (has links)
No description available.
754

Extraction of Weak Target Features from Radar Tomographic Imagery

Almutiry, Muhannad Salem S. 09 September 2016 (has links)
No description available.
755

The Electromagnetic Simulation of Birdcage Coils for MRI based on Finite Element Method

Tadesse, Yonatan Abebe January 2016 (has links)
No description available.
756

A Dirigible Bowling Ball : Controlling a bowling ball to hit a strike every time / Ett styrbart bowlingklot

Fröberg, Joel, Smolic, Magdalena January 2021 (has links)
The purpose of this bachelor’s thesis is to investigate the uses of spherical robots and on a prototype basis construct and control a dirigible bowling ball. The robot is able to steer left and right after being thrown by the user. This occurs due to a weight displacement inside the ball when a weighted pendulum swings left and right by being radio controlled from afar. The goal of the report is to investigate how well this robot will be able to steer and if it can achievea desired strike. Further, this report will investigate the use of Radio Frequency (RF) signals between a hand controller and the ball and at what distance this method will work. This robot is strictly made for scientific purposes, the authors do not advocate cheating in the sport of bowling in any way. / Syftet med denna kandidatuppsats är att undersöka användningen av sfäriska robotar och på en prototypbasis konstruera och styra ett styrbart bowlingklot. Roboten kommer att kunna styras åt vänster och höger efter att ha kastats avanvändaren. Detta inträffar på grund av en viktförskjutning inuti klotet då en viktad pendel svänger åt vänster och åt höger genom att radiostyras på håll. Målet med rapporten är att undersöka hur bra den här roboten kommer att kunna kontrolleras och om en strike kan uppnås med den nya och samlade kunskapen. Vidare kommer användningen av Radio frekventa (RF)-signaler mellan en handkontroll och klotet att undersökas, hur väl detta kan implementeras och även på hur långt avstånd denna metod kan fungera. Denna robot är endast gjord för vetenskapliga ändamål, författarna förespråkar inte fusk i sporten bowling på något sätt.
757

Sustainable reduction of asbestos sample losses using Radio Frequency Identification and the 5S method / Hållbar minskning av asbestprovförluster med hjälp av radiofrekvensidentifiering och 5S-metoden

Falcand, Elie January 2021 (has links)
This study is a research around an issue encountered by MyEasyLab, a laboratory involved in asbestos testing for the French market. They are facing a problem of sample losses, which is hardly acceptable, especially when growing on a highly competitive and price driven market. They are therefore looking for ways to have a better traceability of their samples. The technicians were observed to identify their needs and the problems the company is facing. This study is presenting as a result two complementary solutions: the reorganization of the working space, and the usage of the RFID (Radio Frequency Identification) technology to track the samples. The reorganization of the room using the 5S method should enable a more optimized way of working. This method initially used in the industry early on by Toyota, enables to optimize the flows (goods, person, waste …) in a sustainable way. The use of RFID presents the opportunity of a deep change in the whole process of the company, from the client to the labs. Bags already tagged RFID could be sent to the clients for their sample collection, enabling traceability from the beginning of the chain. The samples could, using RFID, be detected as they enter the site, leave the site and if they are in an undesired location (for example in the trash). The RFID technology is also an opportunity to facilitate the work of the technician, with a possibility to save around 4h15 of working time per day. The kind of tags that seems the most appropriate for this application is passive UHF tags. They present the advantages of being cheaper, easier to buy in bulk and readable from longer distances.  Even though the RFID technology is often seen as expensive, a return on investment seems possible for a tag price under 0.08€.  Further experimental tests need to be realized to refine the results of this study.
758

Modeling of Radio Frequency Heating in JET

Tegkelidis, Christos, Lindström, Erik January 2020 (has links)
This study examines the efficiency of ion cyclotronresonance heating in multi-ion plasmas in JET (Joint EuropeanTorus), using deuterium and tritium as fuel along with smallconcentrations of a third ion species. In particular, two ionminority scenarios, hydrogen and helium, as well as a 3-ionscenario using beryllium were constructed. The scenarios weresimulated with FEMIC and the obtained data was then compiledand analyzed through a number of metrics.The highest total power absorption was 8.56 W and wasachieved by the 4% hydrogen scenario. However, 8% hydrogenattained the highest power partition by the minority ion species.The optimal beryllium concentration regarding absorbed powerwas 0.1% in 36.2% deuterium and 63.4% tritium, with a totalcoupled power of 6.94 W. The highest power partition byberyllium was noted for the 0.25% case in a 36% deuteriumand 63% tritium plasma. / Denna studie undersöker effektiviteten av joncyklotronresonansuppvärmning av JETs (Joint European Torus) plasma, med deuterium och tritium som bränsle, samt små koncentrationer av ett tredje ämne. Mer specifikt undersöks två scenarier med minoritetsjoner, helium och väte, och ett 3-jonscenario med beryllium. För att undersöka dessa olika konstellationer körs simuleringar i FEMIC. Datan som fås från simuleringarna sammanställs och analyseras i enlighet med olika mått. Den högsta totala absorptionen av energi var 8.56 W och fas av 4% väteminoritet. 8% väte ger den högsta energipartitionen för det tredje jonslaget. Beryllium absorberade som mest 6.94 W, detta med 0.1% beryllium, 36.2% deuterium och 63.4% tritium. Den högsta energipartitionen för beryllium uppnåddes med 0.25% beryllium, 36% deuterium och 63% tritium. / Kandidatexjobb i elektroteknik 2020, KTH, Stockholm
759

Study of fade and inter-fade durations in Ku- and Ka- band frequencies using OLYMPUS satellite beacons

Ajaz, Haroon 04 December 2009 (has links)
Fade and inter-fade duration data obtained from the three beacons at 12, 20, and 30 GHz aboard the OLYMPUS satellite were analyzed. The different types of signal impairments and their causes were highlighted and a literature survey conducted. Twelve months of fade and inter-fade data were analyzed and the results of these statistics are presented in the form of tables and figures. The analysis was done on both the monthly and annual data. These tables and figures show that at the higher fade levels, the number of fade events and the fade time is smaller than at the lower thresholds. For the same fade level the number of fade events and the fade time goes down as the fade duration which it exceeds is increased. Inter-fade durations also showed similar results. The fades exhibited seasonal dependencies. The number of fades (and consequently the fade time) were much higher for the months of May through August and for the months of March and December. The other months showed very little fade activity. A model was also constructed that can predict the fade time as a function of frequency, attenuation level, and fade duration interval. The predicted fade times agree well with the measured fade duration data. An alternate simplified version of the model is also presented. / Master of Science
760

Frequency scaling of rain attenuation on satellite links in the Ku/Ka-bands using OLYMPUS satellite data

Laster, Jeff D. 16 June 2009 (has links)
Frequency scaling of attenuation is the prediction of attenuation at a desired frequency from attenuation values at a base frequency. The attenuation at the base frequency is often known from prior measurements. Frequency scaling of attenuation is of interest because of the eventual need to exploit higher frequency bands. Most satellite communications traffic now use C-band (4-8 GHz) and Ku-band (12-18 GHz). The next approved, yet largely unused, frequency allocation for domestic use is in the K-band (18-27 GHz) to Ka-band (27-40 GHz). At these higher frequencies, however, earth-space radio links suffer atmospherically induced impairments as frequency increases. In particular, rain causes severe fading. Consequently, satellite systems in these higher bands are very susceptible to outages due to rain-induced fades. Reliable frequency scaling models are needed in system design to estimate the effect of these rain-induced fades. Between August 1990 and August 1992, V.P.I. & S.U.'s SATCOM Group performed extensive measurements of slant path attenuation using the 12, 20, and 30 GHz beacon signals (in the Ku/Ka-bands) of the European OLYMPUS experimental satellite. The experimental results are used to evaluate the usefulness of scaling models proposed by other researchers, both for instantaneous and statistical purposes. New models are presented for accurate scaling of attenuation within the Ku/Ka-bands. / Master of Science

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