Today’s world is a network of interconnected systems that are always running to facilitate information exchange so people can carry out their daily activities. Software applications are constantly evolving to meet the increasing expectations of the growing market, thereby giving rise to the development of large complex systems. It is very likely for these complex systems to encounter bugs which is a situation that can cause errors in software. These bugs can prevent the systems from operating as intended, slowing down software development and deployment, and causing delays in deadlines. This study undertook a systematic literature review to find trends in the field of bug prioritization. Software bug prioritization can help developers determine the order of fixing bugs by assigning priority levels based on the severity analysis. This study aims to identify the most promising techniques that can change the bug prediction and resolution process. It is observed that machine learning techniques (ML) have been gaining popularity in addressing the bug prioritization issue since they can automatically assign priority levels. However, these ML techniques also have limitations addressed in this study along with a taxonomic classification of identified techniques. The review obtained 34 manuscripts based on study selection criteria. These manuscripts discovered 63 unique bug prioritization techniques, including a mix of ML, data reduction and hybrid techniques. It is evident that though these techniques perform automatic prioritization, they can sometimes be slow and lack consistency in the accuracy of results.

Background: The construction sector is growing rapidly and is on the list among the most significant segments of the global economy. The output from global construction is expected to reach 12 trillion US dollars by 2025. This rapid growth in an industry that has been staying comparatively the same because of the conservative nature of this sector can cause problems. Some companies are depending on old-fashioned habits and practices, which leads to decreased productivity and efficiency. Some trends in this segment impose higher demands in terms of cost, time, sustainability, transparency, and an increased need for accessible technology, equipment, construction materials, and processes. Aim and Purpose: This thesis aims to underline the problems with the current material tracking and material data management in the construction industry. To highlight the limitations and create a minimum viable product, demonstrating the ability to introduce a semi-automated solution to aid the creation of a future circular system. Methods: In this thesis, the Design Research Methodology, together with the Design Thinking methodology, has been used to support the researchers' emphasis on achieving progress and insights regarding the existing issues, conditions, and probabilities. The Design Thinking methodology was used to tackle complex problems which may not have a clear list of needs and requirements. Further, semistructured interviews and observations have been used to gather qualitative data for the project to support decision-making and validity. Results: The result presented is a tracking system with hardware consisting of a probe and a beacon, and software including a database, REST API, MQTT broker, a mobile app, and a website. The system helps companies in the construction industry to easily document, monitor, track, and follow up transportation data and records. It also allows companies to take a step away from the outdated systems and methods, like physical delivery notes, and be more prepared for the future of transportation in the construction industry. Conclusions: An efficient system for data management during transport is absolutely necessary to drive the transition period towards a more sustainable and digitalized construction industry. The proposed solution in this thesis shows the possibilities of digitizing data linked to the transport of soil masses in the construction industry and what benefits this can provide. The next step in further developing this tracking system can be to investigate some of the issues that exist with the embedded tracking system. / Bakgrund: Byggsektorn växer snabbt och är på listan bland de viktigaste segmenten i den globala ekonomin. Produktionen från den globala konstruktionen förväntas uppgå till 12 biljoner US dollar under året 2025. Denna snabba tillväxt i en bransch som har varit relativt sammalunda på grund av den konservativa karaktären av denna sektor kan orsaka problem. Vissa företag är beroende av gammaldags vanor och metoder, vilket leder till minskad produktivitet och effektivitet. Vissa trender inom detta segment ställer högre krav när det gäller kostnad, tid, hållbarhet, transparens och ett ökat behov av tillgänglig teknik, utrustning, byggmaterial och processer. Syfte: Denna avhandling syftar till att understryka problemen med den aktuella materialspårningen och materialhanteringen i byggbranschen. För att lyfta fram begränsningarna och skapa en minimal och effektiv produkt, visa förmågan att införa en halvautomatisk lösning för att underlätta skapandet av ett framtida cirkulärt system. Metod: I denna avhandling har Design Research Methodology, tillsammans med Design Thinkingmetoden, använts för att stödja forskarnas tryck på att uppnå framsteg och insikter om befintliga frågor, förhållanden och sannolikheter. Metoden Design Thinking användes för att kunna angripa de komplexa problemen som eventuellt inte har en tydlig lista över behov och krav. Vidare har halvstrukturerade intervjuer och observationer använts för att samla in kvalitativa data för projektet för att stödja beslutsfattandet och validering av resultat. Resultat: Resultatet som presenteras är ett spårningssystem med hårdvara som inkluderar en Probe och en Beacon, samt en programvara del av systemet som inkluderar en databas, REST API, MQTT-broker, en mobil-app och en webbplats. Systemet hjälper företag inom byggbranschen att enkelt sammanställa, övervaka, spåra och följa upp transportdata och dokument. Det blir även möjligt för företag att ta ett steg bort från föråldrade system och metoder, som fysiska följesedlar, och vara mer beredda på framtiden för transport inom byggbranschen. Slutsatser: Ett effektivt system för datahantering under transport är absolut nödvändigt för att driva fram övergångstiden mot en mer hållbar och digitaliserad byggindustri. Den föreslagna lösningen i denna avhandling visar möjligheterna att digitalisera data kopplade till transport av jordmassor i byggbranschen och vilka fördelar detta kan ge. Nästa steg för att vidareutveckla detta spårningssystem kan vara att undersöka några av de problem som finns med det inbäddade spårningssystemet.

In this research, the use of the SteamVR tracking system as a teaching method forindustrial robots was investigated, in particular, how it can make the setup of weldingapplications more intuitive. Therefore, an application was developed, that handles therecording of the teaching data and the control of the robot, which allow fast setup timesof a few minutes only. Tests were conducted and a static accuracy of 10 mm determinedat the TCP. This is not sufficient for welding. Further investigation of the tracking systemshowed directional dependencies, a slow dynamic response of the tracking, which can addanother 10 mm of error, and deviations at the pose determination between 3 and 20 mm,making this tracking setup only usable for applications, where no precision is needed.

Indiana University-Purdue University Indianapolis (IUPUI) / With the advances in embedded technology and the omnipresence of smartphones, tracking systems do not need to be confined to a specific tracking environment. By introducing mobile devices into a tracking system, we can leverage their mobility and the availability of multiple sensors such as camera, Wi-Fi, Bluetooth and Inertial sensors. This thesis proposes to improve the existing tracking systems, enhanced Distributed Tracking System (e-DTS 2.0) [19] and enhanced Distributed Object Tracking System (eDOTS)[26], in the form of e-DTS 3.0 and provides an empirical analysis of these improvements. The enhancements proposed are to introduce Android-based mobile devices into the tracking system, to use multiple sensors on the mobile devices such as the camera, the Wi-Fi and Bluetooth sensors and inertial sensors and to utilize possible resources that may be available in the environment to make the tracking opportunistic. This thesis empirically validates the proposed enhancements through the experiments carried out on a prototype of e-DTS 3.0.

The purpose of this study was to analyse the tracking systems used to identify patients with tuberculosis who missed a clinic appointment at primary health care facilities in Waterberg District. A quantitative descriptive correlation design was used to determine if there was an association between the tracking systems used and the defaulter rates. Data was collected using a questionnaire with nurses from 46 primary health care facilities, defaulter rates were accessed from the ETR.Net and the two sets of data were correlated. The results showed that the blue folder yielded the lowest mean defaulter rate while the green card yielded the highest mean defaulter rate. Nurses were unaware of the true defaulter rate in their facilities as they underestimated these rates. They therefore did not implement relevant intervention strategies to recall patients or find ways to improve the tracking systems used to reduce the defaulter rate in their health facilities. / Health Studies / M.A. (Health Studies)

Ce travail a pour objet de développer une nouvelle technologie de l’énergie solaire à concentration. Il porte sur la présentation du concept, la réalisation prototypique et l’étude optique et énergétique d’un nouveau concentrateur solaire QingSun™. Ce concentrateur a une forme de parallélépipède rectangulaire et comporte des lentilles de Fresnel linéaires, des parois tapissées de miroir et d’un récepteur solaire mobile entraîné par un système de suivi à l’intérieur du caisson de concentration. Un modèle optique et un modèle énergétique ont été élaborés et validés avec une série d’expériences. Ils ont permis d’étudier le fonctionnement et les performances énergétiques du concentrateur. Une étude de l’influence paramétrique de l’inclinaison et l’orientation a été effectuée et a montré que l’inclinaison a plus d’influence que l’orientation sur les performances. Enfin, les performances énergétiques optimales du concentrateur ont été estimées. / This work is for the purpose to develop a new solar concentrating technology. It covers the presentation of the concept, the prototype realization and the optical and energy study of a new solar concentrator QingSun™. This concentrator has a shape of rectangular parallelepiped and includes linear Fresnel lenses, mirror-lined walls and a mobile solar receptor controlled by a tracking system inside the casing. An optical model and an energy model were developed and validated with a series of experiments. The both models permitted us to examine the function and the energy performance of the concentrator. A parametric study of the influence of the tilt and the orientation was performed and showed that the tilt had more influence than the orientation. Finally, the optimal energy performance of this concentrator was estimated.

Devido à dificuldade em se desenvolver um sistema de controle baseado no modelo da planta, principalmente quando a mesma possui diversos graus de liberdade, busca-se uma metodologia a fim de minimizar o tempo e os esforços para projetar o sistema de controle. A metodologia consiste na utilização de um software de sistemas multicorpos, para a geração do conjunto de equações que descrevem o comportamento dinâmico, a partir de características físicas do sistema, tais como: massa, centro de massa, momentos principais de inércia, dimensões dos elos e juntas com determinados graus de liberdade. Para determinação das características físicas, são utilizadas técnicas experimentais, procedimentos e instrumentação para identificação com acuracidade controlada dos centros de massa e dos momentos principais de inércia dos elos. Estes são considerados corpos rígidos não homogêneos, algumas vezes acoplados por juntas de movimento, não sendo possível desacoplá-los. O sistema de controle utiliza um sistema com realimentação de estados com observador, capaz de fornecer resultados satisfatórios. O observador é utilizado para diminuir o número de estados medidos, facilitando a instrumentação do mecanismo. Esses procedimentos podem ser aplicados à maioria dos sistemas multicorpos, com muitos graus de liberdade, a fim de se obter um sistema de controle com desempenho e acuracidade predefinidos, para serem implementados em sistemas de aquisição e controle flexíveis, ou através de hardwares dedicados. Para validar essa metodologia, esta será aplicada ao protótipo de uma plataforma de movimento que, por conveniência de projeto, teve seus graus de liberdade controlados limitados a dois. Seu acionamento dá-se por servomotores brushless, atuadores de fusos de esferas, utilizando-se sensores de posição linear por magnetostrição e angular ópticos. O fato do número de graus de liberdade ter sido reduzido a dois não invalida a metodologia, caso seja necessário aplicá-la a sistemas com qualquer número de graus de liberdade. / The difficulty to develop a control system based in the model of the plant, mainly when the plant has many degrees of freedom, motivated this work which presents a methodology to minimize the time and effort in developing the control system. The methodology consists on the use of a multibody systems software for generating the set of equations that describes the system dynamic behavior, starting from its physical characteristics such as mass, center of mass, principal moments of inertia, dimensions of the links and joints with certain degrees of freedom coupling the links. For the physical characteristics determination, experimental techniques, procedures and instrumentation are used to identify, with controlled accuracy, the links centers of mass and principal moments of inertia, being the plant considered formed by non homogeneous rigid bodies, sometimes coupled by joints of movement and not being possible to uncouple them. For the control system a state feedback control system with estimator is used, capable of suppling satisfactory results. An estimator is used to reduce the number of measured states facilitating the mechanism instrumentation. Those procedures can be applied to most of multibody systems with several degrees of freedom to obtain a control system with performance and accuracy previously defined to be implemented in a flexible acquisition and control board or dedicated hardware. To validate this methodology, it will be applied to a prototype of a movement platform, which, for project convenience had their controlled degrees of freedom limited to two. The platform is driven by brushless servomotors, has actuators with spindle bearings, using sensors of linear position by magnetostriction and angular by optical principle. The fact of the number of degrees of freedom being reduced to two doesn\'t invalidate the methodology in case it is necessary to apply it to systems with any number of degrees of freedom.

abstract: Unmanned aerial vehicles (UAVs) are widely used in many applications because of their small size, great mobility and hover performance. This has been a consequence of the fast development of electronics, cheap lightweight flight controllers for accurate positioning and cameras. This thesis describes modeling, control and design of an oblique-cross-quadcopter platform for indoor-environments. One contribution of the work was the design of a new printed-circuit-board (PCB) flight controller (called MARK3). Key features/capabilities are as follows: (1) a Teensy 3.2 microcontroller with 168MHz overclock –used for communications, full-state estimation and inner-outer loop hierarchical rate-angle-speed-position control, (2) an on-board MEMS inertial-measurement-unit (IMU) which includes an LSM303D (3DOF-accelerometer and magnetometer), an L3GD20 (3DOF-gyroscope) and a BMP180 (barometer) for attitude estimation (barometer/magnetometer not used), (3) 6 pulse-width-modulator (PWM) output pins supports up to 6 rotors (4) 8 PWM input pins support up to 8-channel 2.4 GHz transmitter/receiver for manual control, (5) 2 5V servo extension outputs for other requirements (e.g. gimbals), (6) 2 universal-asynchronous-receiver-transmitter (UART) serial ports - used by flight controller to process data from Xbee; can be used for accepting outer-loop position commands from NVIDIA TX2 (future work), (7) 1 I2C-serial-protocol two-wire port for additional modules (used to read data from IMU at 400 Hz), (8) a 20-pin port for Xbee telemetry module connection; permits Xbee transceiver on desktop PC to send position/attitude commands to Xbee transceiver on quadcopter. The quadcopter platform consists of the new MARK3 PCB Flight Controller, an ATG-250 carbon-fiber frame (250 mm), a DJI Snail propulsion-system (brushless-three-phase-motor, electronic-speed-controller (ESC) and propeller), an HTC VIVE Tracker and RadioLink R9DS 9-Channel 2.4GHz Receiver. This platform is completely compatible with the HTC VIVE Tracking System (HVTS) which has 7ms latency, submillimeter accuracy and a much lower price compared to other millimeter-level tracking systems. The thesis describes nonlinear and linear modeling of the quadcopter’s 6DOF rigid-body dynamics and brushless-motor-actuator dynamics. These are used for hierarchical-classical-control-law development near hover. The HVTS was used to demonstrate precision hover-control and path-following. Simulation and measured flight-data are shown to be similar. This work provides a foundation for future precision multi-quadcopter formation-flight-control. / Dissertation/Thesis / Masters Thesis Electrical Engineering 2018

The purpose of this study was to analyse the tracking systems used to identify patients with tuberculosis who missed a clinic appointment at primary health care facilities in Waterberg District. A quantitative descriptive correlation design was used to determine if there was an association between the tracking systems used and the defaulter rates. Data was collected using a questionnaire with nurses from 46 primary health care facilities, defaulter rates were accessed from the ETR.Net and the two sets of data were correlated. The results showed that the blue folder yielded the lowest mean defaulter rate while the green card yielded the highest mean defaulter rate. Nurses were unaware of the true defaulter rate in their facilities as they underestimated these rates. They therefore did not implement relevant intervention strategies to recall patients or find ways to improve the tracking systems used to reduce the defaulter rate in their health facilities. / Health Studies / M. A. (Health Studies)

Devido à dificuldade em se desenvolver um sistema de controle baseado no modelo da planta, principalmente quando a mesma possui diversos graus de liberdade, busca-se uma metodologia a fim de minimizar o tempo e os esforços para projetar o sistema de controle. A metodologia consiste na utilização de um software de sistemas multicorpos, para a geração do conjunto de equações que descrevem o comportamento dinâmico, a partir de características físicas do sistema, tais como: massa, centro de massa, momentos principais de inércia, dimensões dos elos e juntas com determinados graus de liberdade. Para determinação das características físicas, são utilizadas técnicas experimentais, procedimentos e instrumentação para identificação com acuracidade controlada dos centros de massa e dos momentos principais de inércia dos elos. Estes são considerados corpos rígidos não homogêneos, algumas vezes acoplados por juntas de movimento, não sendo possível desacoplá-los. O sistema de controle utiliza um sistema com realimentação de estados com observador, capaz de fornecer resultados satisfatórios. O observador é utilizado para diminuir o número de estados medidos, facilitando a instrumentação do mecanismo. Esses procedimentos podem ser aplicados à maioria dos sistemas multicorpos, com muitos graus de liberdade, a fim de se obter um sistema de controle com desempenho e acuracidade predefinidos, para serem implementados em sistemas de aquisição e controle flexíveis, ou através de hardwares dedicados. Para validar essa metodologia, esta será aplicada ao protótipo de uma plataforma de movimento que, por conveniência de projeto, teve seus graus de liberdade controlados limitados a dois. Seu acionamento dá-se por servomotores brushless, atuadores de fusos de esferas, utilizando-se sensores de posição linear por magnetostrição e angular ópticos. O fato do número de graus de liberdade ter sido reduzido a dois não invalida a metodologia, caso seja necessário aplicá-la a sistemas com qualquer número de graus de liberdade. / The difficulty to develop a control system based in the model of the plant, mainly when the plant has many degrees of freedom, motivated this work which presents a methodology to minimize the time and effort in developing the control system. The methodology consists on the use of a multibody systems software for generating the set of equations that describes the system dynamic behavior, starting from its physical characteristics such as mass, center of mass, principal moments of inertia, dimensions of the links and joints with certain degrees of freedom coupling the links. For the physical characteristics determination, experimental techniques, procedures and instrumentation are used to identify, with controlled accuracy, the links centers of mass and principal moments of inertia, being the plant considered formed by non homogeneous rigid bodies, sometimes coupled by joints of movement and not being possible to uncouple them. For the control system a state feedback control system with estimator is used, capable of suppling satisfactory results. An estimator is used to reduce the number of measured states facilitating the mechanism instrumentation. Those procedures can be applied to most of multibody systems with several degrees of freedom to obtain a control system with performance and accuracy previously defined to be implemented in a flexible acquisition and control board or dedicated hardware. To validate this methodology, it will be applied to a prototype of a movement platform, which, for project convenience had their controlled degrees of freedom limited to two. The platform is driven by brushless servomotors, has actuators with spindle bearings, using sensors of linear position by magnetostriction and angular by optical principle. The fact of the number of degrees of freedom being reduced to two doesn\'t invalidate the methodology in case it is necessary to apply it to systems with any number of degrees of freedom.