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Utveckling av produktprototyp för hårdvaruaccelererad bildbehandling / Development of a product prototype for hardware-accelerated image processingAlmgren, Mikael, Ekström, Erik January 2013 (has links)
I dagens samhälle finns inbyggda system i allt från vattenkokare till rymdraketer. För att möta användarnas ständigt ökande krav på prestanda och funktionalitet måste hårdvaran i dessa system utnyttjas optimalt. Detta kan göras genom att konstruera hårdvara specifikt för den aktuella uppgiften eller att använda en mer generell hårdvara, där istället mjukvaran är anpassningsbar. I många fall kan det vara lämpligt, och i vissa fall även nödvändigt, att blanda dessa metoder för att lösa en given uppgift. En kraftfull processor kan exempelvis kompletteras med en accelerator uppbyggd av specifik hårdvara. Delar av lösningen kan genomföras snabbare i dessa acceleratorer vilket leder till ett bättre system. Problemet med denna lösningsmodell är dock att förbindelsen mellan processorn och acceleratorn ofta bildar en flaskhals för data som ska bearbetas. En metod för att minimera denna falskhals är att utveckla både programmerbar logik (FPGA, Field-Programmable Gate Array) och en processor på samma chip. Denna täta integration gör det möjligt att både förenkla och snabba upp kommunikationen mellan FPGA och processor. Xilinx har utvecklat ett sådant system, Zynq-7000, uppbyggd av en dubbelkärning ARM-processor och en kraftfull FPGA. Denna rapport beskriver det arbete som har utförts under detta examensarbete. Syftet med examensarbetet var att undersöka hur en specifik produktprototyp kan implementeras i Zynq-7000. Fokus för arbetet var att undersöka hur den interna kommunikationen bör genomföras och därigenom även hur lösningen bör partitioneras mellan mjukvara och hårdvara. Den tänkta produkten var ett system för bildigenkänning av frukter eller grönsaker för användning i en livsmedelsbutik. Under arbetet har utvecklingskortet ZedBoard, baserat på Zynq-7000, använts som målplattform. / In today's society there are embedded systems in almost everything from toasters to space rockets. In order to meet users’ ever-increasing demands for performance and functionality, the hardware of these systems must be utilized optimally. This can be done by designing hardware specifically for the task, or to use a more general hardware running customizable software. In many cases it may be suitable, and in some cases even necessary, to mix these methods to solve a given task. For example, a powerful processor could be complemented with special designed hardware, called an accelerator, to solve parts of the problem faster. The overall system performance can thus be increased by the use of the accelerators. One problem with this solution is that the connection between the processor and the accelerator may form a bottleneck. One way to reduce the effects of this bottleneck is to tightly integrate programmable logic (FPGA, Field Programmable Gate Array) and a processor on the same chip. This tight integration makes it possible to simplify and speed up the communication between the two units. For example, image processing could be accelerated in the FPGA and the result could then be used in some software application in the processor. This report describes how the work was carried out during this thesis. The main goal of the thesis was to study how a specific product prototype could be implemented using a Zynq-7000 based development board. The focus of this work was to study how the internal communication should be implemented, and there by how the solution should be partitioned between the software and hardware in Zynq-7000. The intended product was a system for image recognition of fruits or vegetables for use in a grocery store. During the work we used a Zynq-7000 based development board called ZedBoard to try our implementations.
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Linear Position Tracking for Controlling a Robotic Arm Using Inertial Sensors : Development of a Robotic Arm and an Inertial Sensor-Based Tracking System / Linjär positionsspårning för att styra en robotarm med hjälp av inertiella sensorer : Utveckling av en robotarm och ett inertiell-sensorbaserat spårningssystemKnobe, Jesper, Pekola, Tobias January 2023 (has links)
In the field of mechatronics, different types of robotic arms are used for various applications. Control of robotic arms from a distance is required in certain situations, such as hazardous environments. The purpose of this thesis was to investigate the feasibility, speed, and accuracy of the movement of a robotic arm following the movement of one handheld Inertial Measuring Unit (IMU). The assessment of accuracy was determined through experiments with pre-established movements and examined responses from the arm. The robot arm has four degrees of freedom and is controlled by integrating and filtering the IMU data to obtain the linear position, and inverse kinematics are used to obtain the arm joint angles required to reach the position. The robotic arm was constructed using Solid Edge 3D CAD, 3D printed in PLA plastic. After construction electronic components were connected and assembled. The programs were implemented in MATLAB, and the data was processed and transferred through the Arduino Integrated Development Environment (IDE). The results indicate that the robotic arm demonstrates good capability in executing given coordinates. The accuracy of the IMU-based position tracking is inconsistent and not suitable for all applications. The system's total speed for reading and executing movements is found to be satisfactory, but improvements in precision are necessary for more demanding implementations. The primary causes of errors in the system are attributed to the precision of the measuring device, manufacturing deviations, and limitations in the IMU calculation. This study contributes to the understanding of linear position tracking using inertial sensors, filtering techniques, and communication between microcontrollers, providing insights for future research and development in the field. / Inom området mekatronik används olika typer av robotarmar för olika tillämpningar. Kontroll av robotarmar på avstånd krävs i situationer som farliga miljöer. Syftet med denna avhandling var att undersöka genomförbarhet, hastighet och rörelseprecision hos en robotarm som följer rörelsen av en handhållen tröghetsmätningsenhet (IMU). Bedömningen av noggrannheten fastställdes genom experiment med förutbestämda rörelser och undersökta svar från armen. Robotarmen har fyra frihetsgrader och styrs genom att integrera och filtrera IMU-data för att erhålla den linjära positionen, och inverskinematik används för att erhålla de nödvändiga armledsvinklarna för att nå positionen. Robotarmen konstruerades med hjälp av Solid Edge 3D CAD, 3D-utskrivet i PLA-plast och elektroniska komponenter monterades. Programmen implementerades i MATLAB och data bearbetades och överfördes via Arduino Integrated Development Environment. Resultaten visar att robotarmen har god förmåga att utföra givna koordinater, men noggrannheten i IMU-baserad positionsspårning är inkonsekvent och inte lämplig för alla tillämpningar. Systemets totala hastighet för att läsa av och utföra rörelser anses vara tillfredsställande, men förbättringar av precisionen är nödvändiga för mer krävande implementeringar. De främsta orsakerna till fel i systemet tillskrivs precisionen hos mätinstrumentet, tillverkningsavvikelser och begränsningar i IMU-beräkningen. Denna studie bidrar till förståelsen av linjär positionsspårning med tröghetssensorer, filtreringstekniker och kommunikation mellan mikrokontroller, vilket ger insikter för framtida forskning och utveckling inom området.
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Robotik im Holzbau: Untersuchung grundlegender Fragen der VorfertigungKuhl, Janina Bea Doreen 01 December 2023 (has links)
Die vorliegende Bachelorarbeit untersucht die Thematik der Vorfertigung im Holzbau und zielt darauf ab, einen umfassenden Einblick zu der Entwicklung, den Praktiken, den Herausforderungen und
Potentialen zu geben. Angesichts des steigenden Fachkräftemangels sowie der wachsenden Nachfrage nach bezahlbarem, qualitativ hochwertigem Wohnraum stellt die Produktion im Werk eine
entscheidende Komponente für die zukünftige Entwicklung der Bauindustrie dar. Dabei wird die Integration von automatisierten Lösungen und Robotik thematisiert. Das Ziel dieser Arbeit besteht
darin, die Möglichkeiten und Herausforderungen der Integration solcher Systeme zu untersuchen und Handlungsempfehlungen für die Umsetzung in Werkhallen abzuleiten.
Um einen ausgewogenen Überblick zu gewährleisten, basiert die Untersuchung auf einer Analyse der traditionellen Vorfertigung und deren Limitation. Dabei werden zusätzlich automatisierte
Technologien berücksichtigt. Ein Hauptaugenmerk liegt darauf, wie Robotik in diesem Kontext den Produktionsprozess optimieren kann. Im Zuge dieser Analyse werden Vorteile wie Effizienzsteigerung, Produktivität, Präzision und Ressourcenmanagement sowie potenzielle Herausforderungen in Bezug auf eine hohe Anfangsinvestition, Schulungsbedarf und Flexibilitätseinschränkungen
herausgestellt.
Die wichtigsten Erkenntnisse, aus der Quellenarbeit und den Experteninterviews, zeigen die wachsende Bedeutung der Integration von Robotik in der Vorfertigung im Holzbau und verdeutlichen die Notwendigkeit weiterer Forschung und Entwicklung in diesem Bereich. Die vorliegende Arbeit legt einen Grundstein für das Verständnis der Vorfertigungsprozesse, die Integrationsmöglichkeit verschiedener Technologien und fördert das Verständnis der Potenziale und Herausforderungen, die mit der Nutzung dieser Technologien einher gehen. ...:1 Einleitung
2 Theoretische Grundlagen der Vorfertigung
2.1 Vorfertigung
2.1.1 Begriffsdefinitionen
2.1.2 Intention und Voraussetzungen der Vorfertigung
2.1.3 Vor- und Nachteile des Bauens mit vorgefertigten Elementen
2.1.4 Kritische Gegenüberstellung zur konventionellen Produktion
2.2 Automatisierung und Digitalisierung im Kontext
2.2.1 Begriffsabgrenzung
2.2.2 Notwendigkeit des Ausbaus der Vorproduktion im Holzbau
2.2.3 Analyse der aktuellen Vorproduktionsprozesse in der Werkhalle
3 Effizienzsteigerung durch Prozessanalysen und Automatisierung
3.1 Identifizierung von Engpässen und Schwachstellen
3.2 Einsatz moderner Technologien und Maschinen
3.2.1 Fertigungsform
3.2.2 Materialzuführung
3.2.3 Varianten des Aufbaus
3.3 Automatisierung – Chancen und Herausforderungen
4 Der robotergestützte Ansatz in der Werksfertigung des Holzbaus
4.1 Einführung in den robotergestützten Ansatz
4.1.1 Grundprinzipien
4.1.2 Aufbau
4.1.3 Konvertierung der Daten
4.1.4 Varianten des Aufbaus
4.1.5 Auswahl des passenden Roboters
4.2 Vor- und Nachteile des robotergestützten Ansatzes
4.3 Anwendungsbeispiel
5 Ergebnisse der Untersuchung
5.1 Gegenüberstellung der Fertigungsmethoden
5.2 Handlungsempfehlung für die Integration in Werkshallen
6 Zusammenfassung und Ausblick
Ehrenwörtliche Erklärung
Literaturverzeichnis
Online - Quellen
Abbildungsverzeichnis
Anhang / This bachelor thesis explores the topic of prefabrication in timber construction and aims to provide a comprehensive insight into the development, practices, challenges and potentials. In view of the
increasing shortage of skilled workers and the growing demand for affordable, high-quality housing, factory production is a crucial component for the future development of the construction industry.
The integration of automated solutions and robotics will be addressed. The aim of this work is to investigate the possibilities and challenges of integrating such systems and to derive recommendations for action for implementation in factory buildings.
To ensure a balanced overview, the study is based on an analysis of traditional prefabrication and its limitations. Automated technologies are also taken into account. A main focus is on how robotics
can optimise the production process in this context. In the course of this analysis, benefits such as increased efficiency, productivity, precision and resource management are highlighted, as well as
potential challenges in terms of high initial investment, training needs and flexibility limitations.The main findings from the source work and the expert interviews show the growing importance of
the integration of robotics in prefabrication in timber construction and highlight the need for further research and development in this area. This thesis lays a foundation for understanding the prefabrication processes, the integration possibilities of different technologies and promotes the understanding of the potentials and challenges associated with the use of these technologies. The work
emphasises the importance of further research and implementation of robotics in prefabrication to ensure the competitiveness and sustainability of the timber construction industry and to drive innovative advances.:1 Einleitung
2 Theoretische Grundlagen der Vorfertigung
2.1 Vorfertigung
2.1.1 Begriffsdefinitionen
2.1.2 Intention und Voraussetzungen der Vorfertigung
2.1.3 Vor- und Nachteile des Bauens mit vorgefertigten Elementen
2.1.4 Kritische Gegenüberstellung zur konventionellen Produktion
2.2 Automatisierung und Digitalisierung im Kontext
2.2.1 Begriffsabgrenzung
2.2.2 Notwendigkeit des Ausbaus der Vorproduktion im Holzbau
2.2.3 Analyse der aktuellen Vorproduktionsprozesse in der Werkhalle
3 Effizienzsteigerung durch Prozessanalysen und Automatisierung
3.1 Identifizierung von Engpässen und Schwachstellen
3.2 Einsatz moderner Technologien und Maschinen
3.2.1 Fertigungsform
3.2.2 Materialzuführung
3.2.3 Varianten des Aufbaus
3.3 Automatisierung – Chancen und Herausforderungen
4 Der robotergestützte Ansatz in der Werksfertigung des Holzbaus
4.1 Einführung in den robotergestützten Ansatz
4.1.1 Grundprinzipien
4.1.2 Aufbau
4.1.3 Konvertierung der Daten
4.1.4 Varianten des Aufbaus
4.1.5 Auswahl des passenden Roboters
4.2 Vor- und Nachteile des robotergestützten Ansatzes
4.3 Anwendungsbeispiel
5 Ergebnisse der Untersuchung
5.1 Gegenüberstellung der Fertigungsmethoden
5.2 Handlungsempfehlung für die Integration in Werkshallen
6 Zusammenfassung und Ausblick
Ehrenwörtliche Erklärung
Literaturverzeichnis
Online - Quellen
Abbildungsverzeichnis
Anhang
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Development of a Semi-Analytic Method to Estimate Forces Between Tool and Hand, Tool and Workpiece in Operation of a Hand-held Power ToolLim, Alvin 13 October 2014 (has links)
No description available.
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Age-related Maculopathy: A Multifocal ApproachFeigl, Beatrix Karoline January 2005 (has links)
Age-related maculopathy (ARM) is a central retinal disease with unclear pathogenesis. It is the major cause of permanent vision loss in adults over 50 years and is increasing in prevalence and incidence, faster than the aging population would suggest. Early in the disease process (early ARM) there is little or no vision loss and there are only slight retinal changes with abnormal deposits within Bruch's membrane. As the disease progresses (late ARM or age-related macular degeneration, AMD) vision loss may be quite severe due to atrophy (dry AMD) or the development of chorioretinal neovascularisation (CNV, wet AMD). It is hard to predict from conventional eye examinations and clinical vision tests which cases will progress to the severe, dry or wet forms of the disease. Moreover, most of the conventional clinical tests are based upon subjective vision measures. Objective tests which detect ARM earlier would be a useful aid to diagnosis and to monitoring progression. The multifocal electroretinogram (mfERG) is a relatively new clinical tool which enables the recording of electrical potentials from multiple, small areas of the central retina and thus assesses function from specific retinal locations. It is therefore useful in detecting focal retinal diseases such as hereditary or acquired maculopathies or in monitoring retinal laser or surgical treatment effects. There is cone and rod impairment in ARM and histopathological and psychophysical evidence for a preferential vulnerability of rods compared to cones. This research project investigated if an objective tool such as the mfERG could detect early ARM,its progression and the treatment effects of multiple photodynamic therapies (PDT) on retinal function in late ARM, prior to a battery of subjective vision measures. For comparison purposes a subjective assessment of central retinal function was performed using high and low contrast distance visual acuities (VA), near VA, low luminance VA (SKILL cards), contrast sensitivity (Pelli-Robson, P-R), saturated and desaturated Panel D-15 (sat Panel D-15, desat Panel D-15) and central visual fields (Humphrey 10-2, mean sensitivity, MS and mean defects, MD). As an objective assessment of central retinal function the cone- and rod-mediated multifocal electroretinograms were recorded. Subjective and objective tests of retinal function were compared in early ARM and an age-matched control group (chapter 3). Seventeen eyes of seventeen subjects with early ARM and twenty control subjects with normal vision were measured. For the cone-mediated mfERG responses conventional averaging methods were used and results were correlated with subjective vision tests. The conventional cone-mediated mfERG failed to distinguish between the early ARM and control subjects whereas subjective vision measures such as HC- and LC-VA, desat Panel D-15, MS, P-R were significantly reduced in the ARM group. However, there were significant correlations between the cone-mediated mfERG and the desat Panel D-15 results in the ARM group. This suggests that the mfERG measures similar retinal processes that detect colour vision deficiency under desaturated conditions. There was no significant correlation between cone-mediated mfERG measures and funduscopic changes. The conclusion from this study was that the subjective vision tests detected early ARM better than the objective cone-mediated mfERG. Thus the aim of detecting early ARM objectively was not met by the cone-mediated mfERG suggesting the need to develop other objective tests such as a rod-mediated mfERG. Whether the preferential rod vulnerability others have reported in early ARM could be detected by the rod-mediated mfERG was determined in the next study (chapter 4). A protocol for recording rod-mediated mfERG responses was developed by determining the optimal testing luminance to reduce the effect of stray light and elicit maximal rod-mediated responses. Sixteen of the seventeen ARM subjects and seventeen control subjects from the previous study were tested. For analysis, a customized computer template fitting method was developed in MATLAB (Mathworks, Natick, MA, USA). This method has been shown to be useful for low signal-to-noise ratio responses that characterize the rod-mediated mfERG. Significantly delayed rod-mediated mfERG responses were found whereas cone-mediated mfERG responses were within the normal range. This suggested that the effect of ARM on the rod system could be detected objectively with the rod-mediated mfERG before changes in the cone-mediated mfERG. Which of the tests best detected progression of vision loss was investigated in chapter 5. Visual function of 26 (13 ARM and 13 control subjects) of the original 37 subjects (17 ARM and 20 control subjects) had cone- and rod-mediated mfERG and the subjective vision measures repeated after one year. The main purpose was to determine which of the tests best detected progression of vision loss. The mfERG results were analysed by using both averaged and local responses and by using the computer template fitting procedure. On average no significant worsening of either objective or subjective function measures was evident after one year. These results reinforce the slow progression of the disease. With a longer follow-up period progression of ARM may translate into measurable changes in the mfERG and the other visual function tests. The effect of multiple photodynamic therapies (PDT) on cone- and rod-mediated function was assessed with the mfERG in the last study (chapter 6). The cumulative treatment effects of PDT in five subjects with late ARM were determined. Having demonstrated that the rod-mediated mfERG was applicable in early ARM, this study also aimed to investigate how useful it was in late ARM where there is substantially greater rod loss. Cone- and rod-mediated mfERGs, visual acuities, contrast sensitivities and central visual fields were investigated a week before treatment began and then one month after each PDT treatment. The subjects received three treatments each over an average period of five and a half months. In some subjects there were significant transient reductions in cone- and rod-mediated amplitudes possibly reflecting alterations in choroidal hypoperfusion dynamics one month after treatment. Further, b-wave component of the mfERG became increasingly misshapen after each PDT treatment suggesting an ischemic insult mainly targeting post-receptoral sites. However, objective and subjective function was stabilized after multiple PDT treatments in most of the subjects. This pilot study of five cases showed that there was no additional damage to cone- and rod-mediated outer retinal function after three PDT treatments. One of the novel findings of this research was that the rod-mediated function measured with the mfERG was impaired in early ARM. This finding supports histopathological and psychophysical evidence of rod vulnerability in early ARM. The results of these studies also suggest that early ARM affects different aspects of visual function which is reflected by different outcomes from objective and subjective vision tests. A model (chapter 7) based upon the results was developed proposing a hypoxic insult with a preferential alteration of post-receptoral sites in early ARM. The cone-mediated mfERG documented the retinal damage and possible treatment effects on outer retinal function of the multiple PDTs which did not further deteriorate. Thus, this technique might assist in the development of optimal treatment modalities for ARM, especially in retreatment regimes. Greater variability was found for the rod-mediated mfERG and its clinical use in PDT treatment regimes still needs to be investigated. In conclusion, this research has provided a better understanding of the disease process and treatment effects in ARM and might contribute to improvements in diagnosis and treatment of ARM.
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Revisionens digitalisering : En kvalitativ studie om hur digitaliseringen påverkar revisionens tillförlitlighet och revisionsrisker / Audit digitization : A qualitative study on how digitization affects the reliability of the audit and audit risksJohansson, Elin, Grönlund, Annica January 2016 (has links)
Sammanfattning Examensarbete i företagsekonomi, Högskolan i Skövde.Kandidatuppsats, Externredovisning, vårterminen 2016 Bakgrund: Datorer har under ett halvt sekel använts i näringslivet och revisorer har använt datorer i revisionsprocessen sedan 1980-talet. Teknik är menat att effektivisera revisionen och möta behov av automatisering för att öka lönsamheten, minska tidsåtgången och underlätta revisorernas arbete. Betydelsen och utnyttjandet av automatisering och informationsteknik [IT] i revisionen har ökat kraftigt under 2000-talet som en följd av den tekniska utveckling som sker i samhället. Revisionsbevis går från papper till elektronisk form och informationssystem [IS] kontrollerar data med lite eller helt utan mänsklig inblandning. Branschens digitalisering innebär flera fördelar som flitigt belyses i litteraturen, medan eventuella nackdelar och risker lämnas obelysta.FAR publicerade år 2013 en framtidsstudie där de önskar förbereda branschen på olika förändringar och vara i framkant för att undvika fallgropar och utnyttja möjligheter. I studien utreds flera framtida drivkrafter och en av dem är digitaliseringen. Flera fördelar med digitaliseringen belyses, men också här missas eventuella nackdelar och risker. Syfte: Syftet med denna studie är att, genom att undersöka dagens yrkesverksamma revisionsutövare syn, öka revisionsbranschen och revisionens intressenters förståelse för hur revisionens tillförlitlighet och revisionsrisker påverkas av digitaliseringen. Metod: Studiens empiriska material samlades in genom en kvalitativ metod. Nio revisorer och tre personer som arbetar med risker inom revision och IT-revision har intervjuats genom elva semistrukturerade intervjuer. Slutsats: Studien har kommit fram till att revisorerna i studien och forskningen är eniga om att digitaliseringen innebär flera positiva effekter för revisionen. Exempelvis en ökad kvalitet på slutprodukten, effektivare revisionsprocess och minskad upptäcktsrisk genom att större datamängder kan analyseras. Det föreligger dock en tvetydighet kring huruvida det påverkar revisionens tillförlitlighet som slutprodukt. Studien har visat att yrkesverksamma revisorer har svårt att se risker med den tekniska utvecklingen. Studien har även visat att revisorerna inte har eller anser sig behöva några speciella IT-kunskaper, samtidigt som forskningen menar att IT-kunskaper är mycket viktiga för revisorernas förmåga att göra kvalificerade riskbedömningar. Nyckelord: Revision, digitalisering, tillförlitlighet, förtroende, revisionsrisk, revisionskvalitet, revisionsautomatisering, IT, teknik, IT-revision, ARM. / Abstract Degree in Business Administration, University of SkövdeBachelor Thesis, Financial Accounting, spring term 2016 Background: Computers have been used for half a century in business and auditors have been using computers in the audit process since the 1980s. Technology is meant to make the audit more efficient and meet the needs of automation to increase profitability, reduce the timescale and facilitate the work of the auditors. The meaning and utilization of automation and information technology [IT] in the audit has increased greatly in the 2000s as a result of technological developments taking place in society. Audit evidence goes from paper to electronic and information systems [IS] controls data with little or no human intervention. The industry digitization has several advantages as extensively illustrated in the literature, but the possible disadvantages and risks left not observed. FAR published in 2013 a prospective study in which they wish to prepare the industry to various changes and be in the forefront to avoid pitfalls and exploit opportunities. The study investigated several future drivers and one of them is digitization. Several benefits of digitization are illuminated, but also this study missed potential disadvantages and risks. Purpose: The purpose of this study is that, by examining today's professionals audit practitioners sight, improve the accounting profession and audit stakeholders' understanding of how the reliability of audit and audit risks are affected by digitization. Method: The study's empirical material was gathered through a qualitative method. Nine auditors and three people working with risk assurance and IT audit have been interviewed through eleven semi-structured interviews. Conclusion: The study has concluded that the auditors of the study and research agree that digitization brings several positive effects for the audit. For example, a higher end product quality, a more efficient audit process and reduced detection-risk as a result of larger amounts of data being analyzed. However, there is an ambiguity as to whether it affects the reliability of the audit as a final product. The study has shown that practicing auditors has difficult to see the risks of technological progress. The study has also shown that the auditors did not have or think they need any special IT skills, but research says that IT skills are very important for the auditor's ability to make qualified risk assessments. Keywords: Audit, digitization, reliability, trust, audit risk, audit quality, audit automation, IT, technology, IT audit, ARM.
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Casting and Analysis of Squeeze Cast Aluminium Silicon Eutectic AlloySmillie, Matthew John January 2006 (has links)
Squeeze casting is the practise of solidifying metals under mechanically applied pressure via a slow displacement of a die volume. It has been shown that squeeze casting enhances the mechanical properties of cast metals. Research into other high integrity casting processes has shown that using techniques that enhance melt quality can further increase the mechanical properties. Therefore a bottom-tapped, bottom-fed squeeze casting machine was designed and built around a pre-existing squeeze casting die designed for uniaxial pressure application. This was used to obtain quantitative metallurgical and microstructural information on the squeeze castings produced, including the effects of common micro-alloying additions of strontium modifier and titanium modifier on the microstructure and hardness of a commercial aluminium silicon eutectic alloy. These were examined using a Taguchi design of experiments approach. It was found that squeeze casting reduced porosity and secondary dendrite arm spacing and increased hardness, and reduced or eliminated increases in porosity and secondary dendrite arm spacing associated with micro-alloying addition. The size of possibly deleterious iron-rich precipitates was reduced, and the morphology of such precipitates changed to a possibly less deleterious form without further alloy additions of manganese. It was also found that melt control and handling is essential for consistent quality of castings in the production of small volume squeeze castings, such as the ones produced in this experimental work.
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e-Pontos: Uma solu??o embarcada de automa??o comercial aplicada a clubes de fidelidade baseado em tecnologia RFID e esmart cardPaiva, Jailton Carlos de 27 July 2012 (has links)
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Previous issue date: 2012-07-27 / In practically all vertical markets and in every region of the planet, loyalty marketers have adopted the tactic of recognition and reward to identify, maintain and increase the yield of their customers. Several strategies have been adopted by companies, and the most popular among them is the loyalty program, which displays a loyalty club to manage these rewards. But the problem with loyalty programs is that customer identification and transfer of loyalty points are made in a semiautomatic. Aiming at this, this paper presents a master's embedded business automation solution called e-Points. The goal of e-Points is munir clubs allegiances with fully automated tooling technology to identify customers directly at the point of sales, ensuring greater control over the loyalty of associate members. For this, we developed a hardware platform with embedded system and RFID technology to be used in PCs tenant, a smart card to accumulate points with every purchase and a web server, which will provide services of interest to retailers and customers membership to the club / Em praticamente todos os mercados verticais e em cada regi?o do planeta, os comerciantes de fidelidade adotaram a t?tica de reconhecimento e recompensa para identificar, manter e aumentar o rendimento de seus clientes. V?rias estrat?gias t?m sido adotadas pelas empresas, e a mais popular entre elas ? o programa de fidelidade, que exibe um clube de fidelidade para gerenciar essas recompensas. Mas o problema com os programas de fidelidade ? que a identifica??o dos clientes e a transmiss?o dos pontos de fidelidade s?o feitas de forma semiautom?tica. Visando isto, o presente trabalho de mestrado apresenta uma solu??o embarcada de automa??o comercial intitulada e-Pontos. O objetivo do e-Pontos ? munir os clubes de fidelidades com ferramental tecnol?gico totalmente automatizado para identificar os clientes diretamente nos pontos de vendas, garantindo um maior controle dos pontos de fidelidade dos membros associados. Para isso, foi desenvolvida uma plataforma de hardware com sistema embarcado e tecnologia RFID que ser? utilizada nos PCs dos lojistas, um smart card para acumular os pontos a cada compra e um servidor web, o qual disponibilizar? servi?os de interesse para os lojistas e os clientes conveniado ao clube
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Robotická ruka / Robotic handPizúr, Lukáš January 2019 (has links)
The aim of this work is to design a robotic hand, which will be controlled by wireless Wi-Fi, will be equipped with a camera and for easier operation will be designed control glove. The first part of the thesis is a theoretical analysis, various variants of sensors are described, which can be used for motion detection, each drive units and their control. Next chapters are focused on used electronic modules and microcontrollers. The second part is practical and is focused on the mechanical design of a five-finger robotic hand and fixing to a robotic arm. Also described is the control electronics of the entire robotic hand and the programmed firmware. Next, the design and implementation of the control glove is described. The last chapter describes the programmed application for the Android operating system.
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Digitizér audiosignálu se záznamem na SD kartu / Audio digitizer using recording to SD cardHarsa, Jan January 2013 (has links)
This thesis deals about a digitizer design. The digitizer is part of air-band monitoring receiver. Requirement is digitalization of two audio signals. The device communicates with PC through USB interface and it provides reading and writing to SD card. The STM32F4DISCOVERY development board with processor STM32F407VGT6 was used for design and function testing. This development kit is supplemented with other peripherals on an extern board (input audio circuits and SD slots). The thesis describes briefly theory for each issue which this project deals with. One part is engaged to the hardware design. Then there is a description of the PC software for the device controlling. The main part of the thesis is about the development of the firmware for MCU, which manages AD conversion, formatting of the voice signal, USB communication (HID and Mass Storage class), recording and reading from the SD card and additional peripherals.
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