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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.
171

Asset Condition Monitoring System : Using IoT and Embedded Technologies

Mavuduru, RajaGanapathiNandan, Nallamilli, Vikas Reddy January 2019 (has links)
Global logistics market is expected to reach US$15.5 trillion by 2023 but many companies loss billions of dollars because of improper handling, theft and tracking problems. Especially when high value goods are transported there is a need to monitor their condition because they can be affected by the environmental changes that might be harmful or due to any dangerous mechanical conditions during transportation. Real time condition monitoring applications serve the purpose of providing alerts, analytics and reports of these harmful or dangerous conditions to ensure that goods are transported without any damage or with minimal damage. This thesis considers how to combine software and hardware solution to monitor different conditions and report during transportation. This report focusses on designing and testing the device for real time condition monitoring of consumer goods package during transportation. The proposed device, called Asset Condition Monitoring System, uses FTP protocol to transfer the GPS information along with monitored information through different sensors as an event over a GSM network to a server. The design can be adapted to any type of product. The prototype developed is equipped with different sensors that assess the environmental conditions along with some of mechanical aspects of the package throughout the transit.  The device is tested in a real time environment and provides information on the possible events that might compromise the integrity of the package. The system enables the customer to assess the quality of the package. The design is based on agile method in a user driven framework. The thesis design, model and tests the condition monitoring system according to the requirements and constraints, which can be different to different assets while considering packaging and mode of transportation. For this project, Seagate Hard Drives are considered as an asset to monitor.
172

Design and Implementation of Multi-core Support for an Embedded Real-time Operating System for Space Applications

Zhang, Wei January 2015 (has links)
Nowadays, multi-core processors are widely used in embedded applications due to the advantages of higher performance and lower power consumption. However, the complexity of multi-core architectures makes it a considerably challenging task to extend a single-core version of a real-time operating system to support multi-core platform. This thesis documents the process of design and implementation of a multi-core version of RODOS - an embedded real-time operating system developed by German Aerospace Center and the University of Würzburg - on a dual-core platform. Two possible models are proposed: Symmetric Multiprocessing and Asymmetric Multiprocessing. In order to prevent the collision of the global components initialization, a new multi-core boot loader is created to allow that each core boots up in a proper manner. A working version of multi-core RODOS is implemented that has an ability to run tasks on a multi-core platform. Several test cases are applied and verified that the performance on the multi-core version of RODOS achieves around 180% improved than the same tasks running on the original RODOS. Deadlock free communication and synchronization APIs are provided to let parallel applications share data and messages in a safe manner.
173

Prototype Development of an A-Mode Ultrasound Based Intrafraction Motion Management System

Hailu, Abebe, Lundqvist, Fredrik January 2013 (has links)
Owing to the steep dose fall-off curves of high precision and accuracy radiation therapy (RT) modalities such as stereotactic body RT (SBRT), treatment plans with extraordinarily small margins to organs at risk (OARs), such as the spinal cord, has been made possible. With this development, patient movements during treatment, i.e. intrafraction motion (IFM), must be monitored more closely. This master thesis was aimed at developing an A-mode ultrasound prototype to detect the motions of the cervical spine as part of an IFM management (IFMM) system. Current IFMM systems have several drawbacks, including invasiveness and indirect measurements. The existing prototype was tested in order to identify areas of improvement. The prototype developed was equipped with a preconditioning circuit that retains the frequency information of the signal. Furthermore, software was developed based on wavelet filtering and enveloping using the Hilbert transform. Multiple logic algorithms were added in order to handle lost signals, competing echoes, echoes from soft tissues etc. The newly-developed prototype was found to have higher accuracy and precision than the pre-existing prototype. It was also more robust when measuring distance to the spine. A difficulty in segmenting the echo for bone arises for low quality signals. Therefore a compromise exists between setup time, including probe adjustment, and signal quality. Future work includes the manufacturing of a new neck rest to enable robust probe adjustment and fixation.
174

An implementation of a real-time water quality monitoring IoT system with 4G connectivity : Catfish - Data and Sensors

Nihl, Ellen, De Bruijckere, Eek January 2021 (has links)
This report is about implementing an Internet of Things (IoT) system that is meant to measure the water quality of the Nissan river located in Halmstad. The system measures the temperature, pH value, turbidity, dissolved oxygen, total dissolved solids and electrical conductivity of the water. The project is named Catfish, and the authors of the report are in the Data and Sensors team. The purpose of the Data and Sensors team is to program the prototype to collect the specified environmental values, combining all functionalities of the prototype in the main code, and sending the data wirelessly to a database in real-time, including creating the database. To collect the data, two Arduino microcontrollers and sensors from DFRobot are used. For the central computing, a Raspberry Pi is used. To send the data in real-time, a 4G dongle is connected to the Raspberry Pi and to transmit the data, the protocol TCP/IP is used. In order to create a local database, SQLite is used, and for the database server, MariaDB is used. The project has succeeded to collect data from the specified sensors, send the data wirelessly over the Internet with the help of a 4G modem, and store the data in a database on a remote temporary server. However, the sensors are not calibrated due to lack of time, which means the data received from the sensors can not be trusted. The server that stores the data is a temporary server implemented by the Data and Sensors team since there was no other place to store the data. / Denna rapporten handlar om en implementation av ett Internet of Things (IoT) system som är menad för att mäta vattenkvalitéen i Nissan i Halmstad. Systemet mäter temperaturen, pH värde, grumlighet, upplöst syre, totalmängden upplösta ämnen och elektrisk konduktivitet i vattnet. Detta projektet heter Catfish och författarna av denna rapport är del av Data och Sensor gruppen. Syftet av Data och Sensor gruppen är att programmera prototypen till att samla de specifierade miljövärdena, kombinera prototypens funktioner i huvud-koden och att skicka datan till en databas trådlöst och i real-tid, vilket inkulderar att skapa databasen.  För att samla datan används två Arduino mikrokontrollers och sensorer från DFRobot. För den centrala datoranvändningen används en Raspberry Pi. För att skicka data i realtid används ett 4G modem som kopplas till Raspberry Pi:n och skickar datan till servern genom TCP/IP. Skapandet av en lokal databas är gjord i SQLite och för databasen i servern används MariaDB.  Projektet har lyckats med att samla data från de specifierade sensorerna, skicka datan trådlöst över Internetet med hjälp av ett 4G modem och lagra datan i en databas i en temporär fjärrserver. Sensorerna är dock inte kalibrerade på grund av tidsbrist, vilket betyder att man inte kan lita på datan från sensorerna. Servern där datan lagras är temporär och implementerad av Data och Sensor gruppen eftersom det inte fanns någon annanstans att lagra datan.
175

A scalable search engine for the Personal Cloud / Un moteur de recherche scalable pour le Personal Cloud

Lallali, Saliha 28 January 2016 (has links)
Un nouveau moteur de recherche embarqué conçu pour les objets intelligents. Ces dispositifs sont généralement équipés d'extrêmement de faible quantité de RAM et une grande capacité de stockage Flash NANAD. Pour faire face à ces contraintes matérielles contradictoires, les moteurs de recherche classique privilégient soit la scalabilité en insertion ou la scalabilité en requête, et ne peut pas répondre à ces deux exigences en même temps. En outre, très peu de solutions prennent en charge les suppressions de documents et mises à jour dans ce contexte. nous avons introduit trois principes de conception, à savoir y Write-Once Partitioning, Linear Pipelining and Background Linear Merging, et montrent comment ils peuvent être combinés pour produire un moteur de recherche intégré concilier un niveau élevé d'insertion / de suppression / et des mises à jour. Nous avons mis en place notre moteur de recherche sur une Board de développement ayant un représentant de configuration matérielle pour les objets intelligents et avons mené de vastes expériences en utilisant deux ensembles de données représentatives. Le dispositif expérimental résultats démontrent la scalabilité de l'approche et sa supériorité par rapport à l'état des procédés de l'art. / A new embedded search engine designed for smart objects. Such devices are generally equipped with extremely low RAM and large Flash storage capacity. To tackle these conflicting hardware constraints, conventional search engines privilege either insertion or query scalability but cannot meet both requirements at the same time. Moreover, very few solutions support document deletions and updates in this context. we introduce three design principles, namely Write-Once Partitioning, Linear Pipelining and Background Linear Merging, and show how they can be combined to produce an embedded search engine reconciling high insert/delete/update rate and query scalability. We have implemented our search engine on a development board having a hardware configuration representative for smart objects and have conducted extensive experiments using two representative datasets. The experimental results demonstrate the scalability of the approach and its superiority compared to state of the art methods.
176

Bezdrátový přenos signálu rozhraní DMX512 / Wireless Signal Transmission of DMX512 Interface

Polóni, Pavol January 2009 (has links)
Master's thesis deals with design and implementation of a system for wireless transmission of DMX signal 512, which is primarily designed for the management of lighting effects. Its electrical specification is based on the EIA485 standard. Text of the work describes the design stage. First is the issue of implied actual protocol DMX 512 or EIA485. Next sign on selecting a suitable architecture for wireless transmission, management and compilation of the block diagrams. Describes the operation of the component selection and circuit implementation of the scheme, which is using the DPS Eagle compiled. In conclusion, this work is to evaluate the results of the proposed system and showing the way to its further development so that it can be realistically implemented in practice.
177

Implementace komunikačního middleware v prostředí Java ME / Implementation of Communication Middleware in JAVA ME

Martinák, Jan January 2009 (has links)
In almost each enterprise there is a software support for business processes. With a growing number of the applications there is an increasing demand to integrate those applications in order to have an effectively working environment, which generates profit. In enterprise applications integration there are few principles, each with their own advantages and disadvantages. However, the message-oriented middleware layer proves to be the best solution to many integration scenarios. This work deals with an enterprise of applications running on multifunction embedded office devices based on Java ME platform, and introduces an in-house developed communication middleware layer to integrate those applications. The resulting software component applies principles of messaging in a printing management SOA environment to communicate with a print server using a designed set of messages.
178

Field Load Data Acquisition with regard to Vibration, Shock and Climate including Self-heating of ECUs

Yadur Balagangadhar, Nakul 06 February 2015 (has links)
For the reliability design of Engine Control Unit devices in motor vehicles, the knowledge of stresses occurring in the field within the product service life is essential. In addition to the environmental influences such as temperature, moisture and humidity, vibration and shock issues are in focus. To ensure the robustness of the products and they are still easily and inexpensively made, they must be interpreted appropriately in the development process. For this, the load spectra for the mechanical influences of road conditions and operating conditions are to be determined. Work will also include temperature and humidity values examined on typical installation locations. The essential everyday situations (commuters, taxi, farmer, ...) should be considered. Existing measurement technology must be combined to this end a comprehensive logger system with communication to the vehicle.
179

Memory Measurement and Message Usage Improvement on an Elevator Embedded System

Arleklint, Tomas January 2019 (has links)
All embedded systems are unique, a design that is suitable for one system can rarely be copied over to another. This inherently makes designing embedded systems difficult. The difficulty is only amplified by the uncertainty of the future requirements as it is developed over time. Being able to continuously validate the performance and the reliability is of great importance to be able to ensure fault proof execution.This thesis explores two areas. A method of tracking the static and dynamic memory usage of a system is crucial to ensure correct functionality under all conditions, and that the implemented hardware will suffice. Multiple possible tools, each functioning uniquely, were developed and tested to find the most suitable for measuring the memory usage of the elevator system. Additionally the message usage, i.e. the way the different units within the studied system communicate with each other, was scrutinized for possible performance and reliability enhancements. A study was made for the most optimal communication protocol, and for how the transmissions could be improved upon.The results show that for this specific system, the best way of calculating the memory usage is with a tool developed within this project. Using this tool it was found that none of the modules in the elevator system use more than 30 % of the available memory during execution. The message usage study shows the most optimal protocol is CAN with the ISO 15765-2 upperlevel protocol, which is the one currently in use. However, improvements to the message transmissions are suggested, such as taking full advantage of the CAN protocol and by implementing message buffers on the receiving end.An important conclusion is that just as there is no unique system design that fits all, there is no memory measurement tool or message usage implementation that fits all systems. Each system has to be analyzed to find the most optimal solution for that particular system. / Alla inbyggda system är unika, en design som passar ett system kan sällan kopieras över till ett annat. Detta leder till att det är svårt att designa inbyggda system. Osäkerheten över framtida systemkrav då systemet utvecklas över tid gör inte designproblemet lättare. Att kontinuerligt kunna validera prestandan och pålitligheten är viktigt för att kunna garantera felfri körning.Detta examensarbete utforskar två områden. En metod för att mäta den statiska och dynamiska minnesanvändningen av systemet är nödvändig för att kunna säkerställa att systemet alltid fungerar som det ska, och att den tillgängliga hårdvaran är tillräcklig. Flera olika verktyg utvecklades och testades för att hitta det som bäst mäter hissens minnesanvändning. Utöver det granskades meddelandeanvändningen, hur de olika enheterna inom det studerade systemet kommunicerar med varandra, för potentiella förbättringar av prestandan och pålitligheten. En studie utfördes för att hitta det mest optimala kommunikationsprotokollet, och för hur av överföringarna kunde förbättras.Resultatet visar att för det här specifika systemet är bästa sättet att räkna ut minnesanvändningen med ett verktyg utvecklat under projektet. Med hjälp av det här verktyget visas att ingen av modulerna i hissystemet använde mer än 30% av det tillgängliga minnet under körning. Studien över minnesanvändningen påvisar att det mest optimala protokollet var CAN och ISO 15765-2 för det övre lagret, vilket är det som används för nuvarande. Dock föreslås förbättringar till hur meddelandena överförs, till exempel genom att utnyttja CAN protokollet till fullo och genom att implementera meddelandebufferts på mottagarsidan.En betydelsefull slutsats som drogs var att på samma sätt som det inte finns en unik systemdesign som passar alla system, finns det inte heller ett minnesanvändningsverktyg eller en meddelandeanvändning som passar alla system. Varje enskilt system måste analyseras för att hitta den mest optimala lösningen för det specifika systemet.
180

Automatiserad elektrisk testning av styrenheter : Styrenheter med verkliga laster i befintliga testriggar / Automated electric testing of electronic control units : Electronic control units with actual loads in existing testrigs

Wernersson, Johan January 2017 (has links)
I detta examensarbete utreddes huruvida elektriska tester av styrenheter för tunga fordon kan automatiseras på befintliga testmiljöer. Arbetet utfördes på uppdrag av Scania CV AB för arbetsgruppen Electronic Hardware som utför tester vid utveckling och verifiering av krav på styrenheter. Genom en automatiserad testprocess kan testarbetet effektiviseras och kvaliteten höjas. Testarbetet sker på testriggar som innehåller fullskalig hårdvara från lastbilar för att kunna emulera styrenhetens autentiska arbetsmiljö. För att komma fram till ett testsystem som kunde leva upp till de krav och behov som formulerats inom kravprocessen i arbetet användes utvecklingsmodeller. Utvärderingsmatriser användes för att välja den mjuk- och hårdvara som skulle vara mest lämplig för det automatiserade testsystemet utifrån kraven. Resultatet visade att testsystemet skulle bestå av en testprogramvara som körs på en vanlig persondator och ett inbyggt system med elektroniska komponenter för att kunna utföra de elektriska testerna. För att demonstrera testsystemets möjligheter i ett helhetstest konstruerades en prototyp som har funktionalitet att utföra ett testfall som kan dra stor nytta av att automatiseras, nämligen att testa omslagsnivåer för en digital ingång. Prototypen baserades på ett mikrokontrollerkort från Arduino och ett kretskort konstruerades till detta för att kunna utföra elektriska tester med högre spänningsnivåer som krävs för styrenheter på Scaniafordon. För att utforma testfall och hantera testprocessen valdes LabVIEW, en programvara där tester designas med ett grafiskt programmeringsspråk. Testresultaten för prototyptestsystemet visade att verifieringen av kraven för omslagsnivåer förenklas radikalt vid ett automatiserat förfarande, eftersom testtiden kunde minskas drastiskt, i synnerhet vid ett repetitivt förfarande. / This thesis work intends to study the possibilities to automate electrical testing of electronic control units in an existing test environment. The work was executed on behalf of Scania CV AB for the department Electronic Hardware, who run tests in development and verification of requirements for electronic control units. By using an automated testing system, the testing process could be made more effective and raise the quality. The testing work is done on test rigs which are equipped with full-scale hardware from real trucks to emulate the working environment the electronic control unit operates into. Development models were used to be able to create a testing system which could meet the requirements that were defined during the requirement engineering process. Evaluation matrices were used to choose the soft- and hardware that could be considered the most appropriate for the automated testing system according to the requirements. The result shown that the testing system should consist of a testing software that runs on an ordinary computer and an embedded system equipped with electronic components to enable the testing system for electrical tests. To demonstrate the possibilities of the whole testing system a prototype was manufactured which was designed to execute a test case that could greatly benefit from the advantages that comes with automation. It was a test case set out to measure voltage levels when switching in a digital input. The prototype was based on a microcontroller card from Arduino and was joined by a printed circuit board to be able to run electrical tests with the higher voltage levels that were demanded by electronic control units. To design test cases and manage the test process, LabVIEW was chosen, a software in which tests are designed in a graphical programming language. Test results for the prototype test system showed that verification of the requirements for voltage levels when switching was radically simplified by an automated procedure, as the test time could be drastically reduced, particularly in a repetitive procedure.

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