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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.
1

Interrogation of on-line images of bulk particulate materials

Maxwell, Andrew Paul January 2000 (has links)
No description available.
2

Experimental manure handling systems for reducing airborne contamination

Stewart, Karen 05 January 2005
A laboratory was built at Prairie Swine Centre Inc. (PSCI) to study air quality in swine barns and its effect on pigs and people. The first focus of that research program was to design and test a manure handling system to control the air contamination from the excreta. The goal was to get close to zero air contamination from manure with these systems, in order to measure the contamination from other sources, and to also have a range of contamination levels for future health and productivity testing. Two manure handling systems were designed and tested: a washing gutter system with pressurized heated wash water periodically directed across the dunging area, and a washed inclined conveyor belt used directly as a dunging area. Ammonia emissions were used as a measure of the air contamination originating from the excreta in two experimental chambers. Ammonia originates only from the manure and is released quickly from any manure (especially urine) in contact with the air. Both systems were tested with 30 kg pigs at running time intervals of 30, 60 and 120 minutes. Trials lasted one week, with three trials completed at each frequency. The average ammonia emissions from the washing gutter and the conveyor belt systems were 48.7 mg day-1 kgpig-1 and 57.0 mg day-1 kgpig-1, respectively. Even though these emissions were 38% and 47% lower than previous observations from grower-finisher rooms with a pit plug design in the same swine building, both systems failed to give the desired close-to-zero contamination. This means another system will have to be found to totally eliminate air contamination from manure in the chambers when testing for the origin of the individual contaminants. There were no differences at a statistically significant level (P>0.05) between the ammonia emissions from the two manure handling systems or the three frequencies tested. However, the washing gutter system was simpler and easier to run, and is recommended for future studies dealing with the effects of different ranges of air quality on pigs and people.
3

Experimental manure handling systems for reducing airborne contamination

Stewart, Karen 05 January 2005 (has links)
A laboratory was built at Prairie Swine Centre Inc. (PSCI) to study air quality in swine barns and its effect on pigs and people. The first focus of that research program was to design and test a manure handling system to control the air contamination from the excreta. The goal was to get close to zero air contamination from manure with these systems, in order to measure the contamination from other sources, and to also have a range of contamination levels for future health and productivity testing. Two manure handling systems were designed and tested: a washing gutter system with pressurized heated wash water periodically directed across the dunging area, and a washed inclined conveyor belt used directly as a dunging area. Ammonia emissions were used as a measure of the air contamination originating from the excreta in two experimental chambers. Ammonia originates only from the manure and is released quickly from any manure (especially urine) in contact with the air. Both systems were tested with 30 kg pigs at running time intervals of 30, 60 and 120 minutes. Trials lasted one week, with three trials completed at each frequency. The average ammonia emissions from the washing gutter and the conveyor belt systems were 48.7 mg day-1 kgpig-1 and 57.0 mg day-1 kgpig-1, respectively. Even though these emissions were 38% and 47% lower than previous observations from grower-finisher rooms with a pit plug design in the same swine building, both systems failed to give the desired close-to-zero contamination. This means another system will have to be found to totally eliminate air contamination from manure in the chambers when testing for the origin of the individual contaminants. There were no differences at a statistically significant level (P>0.05) between the ammonia emissions from the two manure handling systems or the three frequencies tested. However, the washing gutter system was simpler and easier to run, and is recommended for future studies dealing with the effects of different ranges of air quality on pigs and people.
4

Separátor horniny / Rock Separator

Menoušek, Martin January 2012 (has links)
The aim of this master´s thesis is to design rock separator. It´s the mechanism, which separates clay from pirites. Main parametre which has been used in proposal is transporting kapacity 5 t/h.
5

Strong winds in extratropical cyclones

Slater, Tim Paul January 2015 (has links)
This thesis was funded by the Natural Environment Research Council (NERC) and is presented in an alternative thesis format. The thesis consists of three separate journal articles which form a coherent research project. Paper 1 investigates the development of strong winds in a dry, idealised extratropical cyclone using the horizontal momentum equation. In particular, the southwest wind maximum that develops was found to contain air parcels from three airstreams. The development of the horizontal along-flow forces around the cyclone and along trajectories entering the southwest wind maximum were analysed. An attempt to extend this methodology to a moist, idealised extratropical cyclone was made. However, the effect of adding moisture to the initial condition was found to be negligible. The reasons for this are explored in Paper 2, which documents this finding: that the effect of moisture on the development of an idealised, baroclinic wave is sensitive to the choice of initial condition. Paper 3 applies the horizontal momentum equation diagnostics to an intense, marine extratropical cyclone that brought strong winds to Ireland and the United Kingdom on 12 February 2014. The development of strong winds in Cyclone Tini was investigated by turning off latent heat release and surface fluxes. In the absence of latent heat release a weaker wind maximum developed. However, the simulation without surface fluxes had a very similar vertical structure of the horizontal wind to the full-physics simulation, but a weaker surface wind maximum. The reason for this weaker wind maximum was analysed using the quasigeostrophic omega equation. This analysis demonstrated a maximum in forcing for descent southwest of the low both in the full-physics simulation and in the simulation without surface fluxes, however strong winds were prevented from reaching the surface in the simulation without surface fluxes because of a more stable boundary layer around the bent-back front.
6

Mechanický manipulátor / Mechanical manipulator

Kopecký, Vojtěch January 2010 (has links)
The aim of this thesis is to design a mechanical manipulator. Work includes variants kinematics stroke belt conveyor, belt functional calculations belt and roller conveyor and risk analysis (the basis for the Declaration of Conformity) and FMEA analysis.
7

An Interactive Digital Manual For Safety Around Conveyor Belts In Surface Mining

Worlikar, Poonam 09 July 2008 (has links)
Belt conveyor accidents are mainly attributed to negligence of safety procedures during maintenance work. Entanglement, falling from heights, & collapse of structure or loose materials are the main cause of accidents. While performing maintenance tasks such as cleaning, installation and repair, belt alignment and so on (Lucas et. al. 2007). Current industry safety programs provide general guidelines for safety training, but do not require any specific training program structure (Shultz, 2002 and Shultz, 2003). For example MSHA (Mine Safety and Health Administration) only requires 24 hours of training. Typically this training is broken down into four hours of training before the employee starts work, the remaining 20 hours has to be performed within the first sixty days of work (Goldbeck, 2003). The information collected through site visits showed that in addition to completing MSHA safety training requirements companies try to reinforce safety issues through daily and weekly safety meetings on job sites. Due to lack of a required safety training structure, every company is independent in terms of their training format that they follow to train their new and experienced work force. As a result, safety engineers depend heavily on in-house safety programs (e.g. audio-video presentations) to deliver the required training hours specified by MSHA for miners. Based on a review of current training methods this research identifies four problems; existing training methods to educate miners about dangers involved in conveyor belt environments are mainly passive, safety related information in scattered in various media such as images, videos, paper manuals, etc., access to information in current format is difficult, and updating information is difficult. This research addressed these identified problems by devising a new approach of learning to augment existing methods of training and evaluate the potential of this concept as a safety-training tool. Research has shown that individuals have their own learning style in which they can increase their retention and stimulate their cognitive learning. The proposed work addresses issues relative to passive vs. active learning and classroom-based vs. self-paced training by developing and implementing an interactive multimedia-based safety-training tool called the Digital Safety Manual (DSM). After the DSM was developed it was put through a series of usability evaluation and subjective analysis to measure the potential of the concept. The evaluation and subjective analysis involved both the novice and expert users. The results that were yield after the evaluations and subjective analysis shows that the DSM has more learning advantages than the typical training methods and it can be used as a supplementary training method to complement the current approaches of training. / Master of Science
8

Contribution à l'étude du comportement mécanique des carcasses textiles de bandes transporteuses : optimisation de la jonction / Contribution at the conveyor belt solid woven mechanical behaviour study : junction optimisation

Roessner, Daniel 19 November 2010 (has links)
La bande transporteuse est utilisée dans l’industrie pour acheminer de la matière ou des objets dans de multiples domaines d’applications tels que les mines souterraines ou aériennes, les carrières, l’industrie alimentaire, l’industrie agricole ou les supermarchés. Ses composants lui permettent de travailler dans des conditions extrêmement difficiles. L’intérêt est porté sur les bandes transporteuses de mines de fond dont les contraintes de fonctionnement et d’acheminement sont particulières. En effet, la bande est acheminée sur rouleaux et jonctionnée sur le site de l’utilisateur pour former une bande sans fin. La jonction est le point faible de la bande transporteuse car sa résistance représente 50% seulement de la force de rupture nominale de la bande. L’objet de cette étude est de proposer une nouvelle solution de jonctionnement.Après avoir analysé les différentes contraintes mécaniques et chimiques auxquelles la bande transporteuse est soumise, une étude comparative sur les différents types de jonctions a été menée.Il y a les jonctions chimiques et les jonctions mécaniques. Chacune a des avantages et des inconvénients en termes de coût ou de longévité, qui ont été présentés. Dans un troisième temps, une étude a été menée sur la compréhension du comportement de rupture de la jonction mécanique. L’étude sur la jonction a été réalisée à l’aide d’un montage expérimental conçu spécifiquement. L’influence des paramètres de la jonction a pu être évaluée grâce à un nouvel indicateur adimensionnel représentant l’efficacité de la jonction par rapport à la bande normale (Junction Tensile Strength Efficiency : JTSE). Dans un quatrième temps, une étude a été faite sur un système de jonction innovant par couture. La jonction réalisée a été testée sur un banc de traction pour en vérifier l’efficacité, puis des essais ont été effectués sur un banc dynamique pour en étudier la fatigue. La jonction cousue est une innovation qui permet de dégager de nouvelles perspectives dans le jonctionnement des bandes transporteuses. / The conveyor belt is used as a material and object transportation tool in a lot of industries such as underground mines, quarries, food industries, agribusinesses or supermarkets. The studied subject is the underground mine conveyor belt, because of their transportation and use difficult conditions.Indeed, the conveyor belt must be cut to be dispatched using belt reeling and joined afterwards in the underground mine forming an endless belt. However, the junction is the weakest part of the conveyor belt due to the 50% belt weakening. The aim of this study is to propose a new junction solution. After analysing the underground belt mechanical and chemical use conditions, the different junction types have been analysed. A junction advantage and inconvenience comparison has been presented. Then, the junction mechanical behaviour has been studied using an original mechanical setup reproducing the mechanical junction. The different parameter influence has been evaluated using a new adimensional indicator called junction tensile strength efficiency. In the last part, a new junction solution made by a sewn has been explored. The sewn junction tensile efficiency has been tested on a tensile strength machine and its fatigue efficiency has been verified through dynamic tests. New outlines in the conveyor belt joining are open as a result of the sewn junction solution development.
9

Understanding the dynamics of a tunnel oven : Use of infrared sensors to measure the temperature of the conveyor belt in a tunnel oven used in bread production.

Sanches, José Afonso January 2018 (has links)
During the continuous production of bread sometimes there are problems that lead to interruptions in the production and consequently to quality problems. One such problem is the bread burning in the contact area between the bread and the conveyor belt. In order to understand the problem and to know how to quantify it, it is necessary to understand what a thermodynamic system is and what types of systems exist, how the various types of heat transfer are processed, how to measure the temperature of an object by infrared radiation and some mathematical methods such as the least square root method. Temperature measurements were planned and carried out. The goal with the first experiment was to understand how the temperature of the conveyor belt varies during an interruption. All the other tests were done to investigate the effects of different solutions in the temperature variation of the belt. According to the results, the best solution is to turn off the oven during an interruption and the worst to spray the belt with water. To spray the belt with water may be a better solution than these results shows, but it is very affected by other problems, like depositions of limestone on the nozzles. A lot more solutions could be found but due to the time available, it was not possible to investigate all the variables/solutions in the process. A long-term  study would help understand much more within the regulation of the industrial baking process. / Under kontinuerlig produktion av bröd finns det ibland problem som leder till avbrott i produktionen och kvalitetsproblem. Ett sådant problem är att brödet blir bränt  i kontaktytan mellan brödet och transportbandet. För att förstå problemet och veta hur man kvantifierar detta,  är det nödvändigt att förstå vad ett termodynamiskt system är och vilka typer av system finns, hur olika typer av värmeöverföring sker, hur man mäter temperatur med hjälp av infraröd strålning och några matematiska metoder som minst kvadratrotsmetoden. Temperaturmätningar planerades och genomfördes. Målet med det första experimentet var att förstå hur transportbandets temperatur varierar under ett huppehåll. Alla andra tester utförades för att undersöka effekterna av de olika lösningarna i bandets temperaturvariation. Enligt resultaten är den bästa lösningen att stänga av ugnen under ett uppehåll och det värsta att spreya bältet med vatten. Att spreya bältet med vatten kan vara en bättre lösning än vad resultaten visar, men det påverkas mycket av andra problem, som avsättningar av kalksten på munstyckena. Många fler lösningar kunde hittas men det var inte möjligt att undersöka alla variabler / lösningar i processen på grund av tillgänglig tid. En långsiktig studie skulle hjälpa till att förstå mycket mer inom regleringen av industriell bakning.
10

Optimalizace uspořádání lisovací linky na výrobu reflektorů ve firmě Automotive Lighting / Optimum layout of pressing line for the production of reflectors at Automotive Lighting

Šťastný, Michal January 2012 (has links)
This thesis deals with optimization of a press line part for the manufacture of reflectors present at the Automotive Lighting Company, Jihlava. The first part focuses on describing the current workplace layout of the press line. The workplaces are located inconveniently and thus require a larger number of operators and a considerable amount of manual work. The second part of the thesis proposes layout solutions for the injection presses and for other machine parts. At the same time, a smoother transition design is proposed for the press line and for the manufacturing section that follows. Based on an evaluation of selected criteria, the optimum version is chosen, thereby adding to the efficiency of the molding process by reducing the number of operators required, by lowering the proportion of manual work relative to other activities, and by limiting the risk of poor quality. The conclusion of the thesis sums up the necessary investment costs and offers an economic assessment of introducing the selected press line arrangement to operation.

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