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The challenge of transitioning to an environmentally sustainable system of production and consumption is both a major risk and a significant opportunity for companies involved in the design and manufacture of products. One approach that might assist companies in meeting this challenge is ‘eco-innovation’, which aims to deliver new products and processes that provide customer and business value but significantly decrease environmental impacts. <br /> The aim of the research was to understand how eco-innovation tools can be developed and introduced to a company such that they are adopted into the long-term practices of the company and contribute to the development of eco-innovative products. A ‘toolbox for eco-innovation’ was developed by adapting existing innovation tools for the purposes of eco-innovation. The initial toolbox was tested through in-house trials before subsequent trials in industry with a refined suite of tools. One-day workshops were held with six producers of electrical and electronic equipment. Four of these companies went on to participate in more in-depth tool introduction studies in which the tools were customised to the specific needs of the company and its design team. Formal tool feedback sessions and individual interviews with members of the design team were used to asses the effectiveness of the tool customisations. The organisational drivers and barriers for the long-term adoption of eco-innovation tools were also investigated. <br /> The contributions to knowledge of this research are: <br /> <ul> <li>The development of a toolbox for eco-innovation.</li> <li>The validation of tool customisation as an approach to improving the introduction of eco-innovation tools.</li> <li>The definition of a generic process for tool introduction based on tool customisation which is appropriate for workshop-based design and innovation tools (including eco-innovation tools).</li> <li>Insights into the organisational drivers and barriers for the long-term adoption of eco-innovation tools.</li> <li>A model for the management of eco-innovation activities. </li> </ul>

The usability of an application often plays an important role in determining its success. Accordingly, organizations that develop software have realized the need to integrate usability engineering into their development lifecycles. Although usability practitioners have successfully applied usability engineering processes to increase the usability of user-interaction designs, the literature suggests that usability practitioners experience a number of difficulties that negatively impact their effectiveness. These difficulties include identifying and recording critical usability data, understanding and relating usability data, and communicating usability information. These difficulties are particularly pronounced for novice usability practitioners. With this dissertation, I explored approaches to address these difficulties through tool support for novice usability practitioners. Through an analysis of features provided by existing tools with respect to documented difficulties, I determined a set of desirable tool features including usability problem instance records, usability problem diagnosis, and a structured process for combining and associating usability problem data. I developed a usability engineering tool, the Data Collection, Analysis, and Reporting Tool (DCART), which contains these desirable tool features, and used it as a platform for studies of how these desirable features address the documented difficulties. The results of the studies suggest that appropriate tool support can improve the effectiveness with which novice usability practitioners perform usability evaluations. More specifically, tool support for usability problem instance records helped novice usability practitioners more reliably identify and better describe instances of usability problems experienced by participants. Additionally, tool support for a structured process for combining and associating usability data helped novice usability practitioners create usability evaluation reports that were of higher quality as rated by usability practitioners and developers. The results highlight key contributions of this dissertation, showing how tools can support usability practitioners. They demonstrate the value of a structured process for transforming raw usability data into usability information based on usability problem instances. Additionally, they show that appropriate tool support is a mechanism for further integrating usability engineering into the overall software development lifecycle; tool support addresses the documented need for more usability practitioners by helping novices perform more like experts. / Ph. D.

Wireless Sensor Network (WSN) is an emerging multi-hop wireless network technology, and the greenhouse network monitoring system is one of the key applications of WSNs in which various parameters such as temperature, humidity, pressure and power can be monitored. Here, we aim to study the performance of a simulation-based greenhouse monitoring system. To design the greenhouse monitoring system based on WSN, we have used ZigBee-based devices (end devices, routers, coordinators, and actuators. Our proposed greenhouse monitoring network has been designed and simulated using the network simulator OPNET Modeller.The investigation is split into two; first, the aim is to find the optimal Transmit (Tx) power set out at sensor nodes and second, the focus is on studying how increasing the number of sensor nodes in the same greenhouse network will affect the overall network performance. ZigBee-based greenhouses corresponded to 4 network scenarios and are simulated using OPNET Modeller in which 22 different transmit (Tx) power (22 cases) in Scenario 1 is simulated, scenario 2, 3 and 4 estimated to 63, 126, 189 number of sensor nodes respectively. Investigating the performance of the greenhouse monitoring network performance metrics such as network load, throughput, packets sent/received and packets loss are considered to be evaluated under varied transmit (Tx) power and increasing number of sensor nodes. Out of the comprehensive studies concerning simulation results for 22 different transmit (Tx) power cases underlying the greenhouse monitoring network (Scenario1), it is found that packets sent/received and packets loss perform the best with the transmitted (Tx) power falling in a range of 0.9 mWatt to 1.0 mWatt while packet sent/received and packet loss are found to perform moderately with the transmitted (Tx) power values that lie in a range of 0.05 mWatt to 0.8 mWatt. Less than 0.05 mWatt and greater than 0.01 microWatt Tx power experience, the worst performance in terms of particularly packet dropped case. For instance, in the case of the packet dropped (not joined packet, i.e., generated at the application layer but not able to join the network due to lack of Tx power), with a Tx power of 0.01 mWatt, 384 packets dropped with a Tx power of 0.02 and 0.03 mWatt, 366 packets dropped, and with a Tx power of 0.04 and 0.05, 336 packet dropped.While increasing the number of sensor nodes, as in scenario 2, 3 and 4, dealing with sensor nodes 63, 126 and 189 correspondingly, the MAC load, MAC throughput, packet sent/received in scenario 2 are found to perform better than that of scenario 3 and scenario 4, while packet loss in scenarios 2, 3 and 4 appeared to be 15%, 12% and 83% correspondingly.

Industries such as automotive and industrial automation are pushing the limits of networking technology. The Time-Sensitive Networking (TSN) standards offer a promising solution that can meet the demands of high-bandwidth applications with strict timing constraints, allowing time-critical traffic to coexist with other traffic. However, TSN is relatively new, with much research necessary before it is usable in the industry. This thesis addresses the problem of the common manual configuration of end stations, being time-consuming and error-prone. Through exploring the TSN standards, this thesis attempts to solve the configuration problem by providing a proof-of-concept for both design and implementation of a software architecture managing the end stations and automating their configuration process. Adopting an agile and iterative approach made the complexity of TSN manageable. Furthermore, this thesis has been guided by the research question: How can the configuration of a TSN end station be automated? The design was split into three components: an interface, a configuration manager, and a TSN library. In addition, a communication protocol between the end stations and the Centralized Network Configuration (CNC) is established. The implementation of the proposed design used Python for all three modules in the end station management software, with the REST protocol for the interface. After presenting the implementation, it was evaluated to show the performance of the implemented end station management software. The results showed that the management software would likely not be the bottleneck, as other components it depends on are considerably slower. This thesis and its research contribution offer a practical foundation for continued research and development, such as investigating the configuration of the end stations, providing proofs-of-concept for engineering tools with specific use cases, and finalizing a TSN system. / Industrier som fordons- och industriautomation tänjer på gränserna av nätverksteknik. Time-Sensitive Networking (TSN) standarderna är en lovande lösning som lovar att möta kraven för applikationer med krav på hög bandbredd och strikta tidskrav, som samtidigt tillåter tidskritisk trafik att existera tillsammans med annan trafik. Dock är TSN relativt nytt och i stort behov av mer forskning innan det kan användas i industrin. Den här avhandlingen adresserar problemet med manuell konfiguration av ändstationer, som är både tidskrävande och felbenäget. Genom att utforksa TSN standarderna försöker den här avhandlingen lösa konfigurationsproblemet genom att ta fram ett koncept för design och implementation av en mjukvaruarkitektur för att hantera ändstationer och automatisera deras konfigurationsprocess. Genom att anta en agil och iterativ metod blev komplexiteten hos TSN hanterbar. Dessutom har den här avhandlingen styrts av forskningsfrågan: Hur kan konfigurationen av TSN ändstationer automatiseras? Designen delades upp i tre komponenter: ett gränssnitt, en konfigurationshanterare, samt ett TSN-bibliotek. Utöver detta etablerades ett kommunikationsprotokoll mellan ändstationer och en Centralized Network Configuration (CNC). Implementationen av den föreslagna designen använde sig av Python för de tre komponenterna, med REST-protokollet för gränssnittet. Efter presentationen av implementationen utvärderades den för att visa prestandan hos den implementerade mjukvaran för ändstationen. Resultaten visade att mjukvaran sannolikt inte skulle vara en flaskhals, då andra komponenter som den är beroende av, är betydligt långsammare. Den här avhandligen och dess forskningsbidrag erbjuder en praktiskt grund för fortsatt forskning och utveckling, som undersökning av konfigurationen för ändstationer, framtagning av koncept för ingenjörsverktyg med specifika användningsfall, samt att slutföra ett TSN-system.

This dissertation develops a new model transformation approach that supports engineering model integration, which is essential to support contemporary interdisciplinary system design processes. We extend traditional model transformation, which has been primarily used for software engineering, to enable model-based systems engineering (MBSE) so that the model transformation can handle more general engineering models. We identify two issues that arise when applying the traditional model transformation to general engineering modeling domains. The first is instance data integration: the traditional model transformation theory does not deal with instance data, which is essential for executing engineering models in engineering tools. The second is syntactical inconsistency: various engineering tools represent engineering models in a proprietary syntax. However, the traditional model transformation cannot handle this syntactic diversity. In order to address these two issues, we propose a new multi-layer syntactical model transformation approach. For the instance integration issue, this approach generates model transformation rules for instance data from the result of a model transformation that is developed for user model integration, which is the normal purpose of traditional model transformation. For the syntactical inconsistency issue, we introduce the concept of the complete meta-model for defining how to represent a model syntactically as well as semantically. Our approach addresses the syntactical inconsistency issue by generating necessary complete meta-models using a special type of model transformation.

Multiprotocol Label Switching (MPLS) is an emerging technology which ensures the reliable delivery of the Internet services with high transmission speed and lower delays. The key feature of MPLS is its Traffic Engineering (TE), which is used for effectively managing the networks for efficient utilization of network resources. Due to lower network delay, efficient forwarding mechanism, scalability and predictable performance of the services provided by MPLS technology makes it more suitable for implementing real-time applications such as voice and video. In this thesis performance of Voice over Internet Protocol (VoIP) application is compared between MPLS network and conventional Internet Protocol (IP) network. OPNET modeler 14.5 is used to simulate the both networks and the comparison is made based on some performance metrics such as voice jitter, voice packet end-to-end delay, voice delay variation, voice packet sent and received. The simulation results are analyzed and it shows that MPLS based solution provides better performance in implementing the VoIP application. In this thesis, by using voice packet end-to-end delay performance metric an approach is made to estimate the minimum number of VoIP calls that can be maintained, in MPLS and conventional IP networks with acceptable quality. This approach can help the network operators or designers to determine the number of VoIP calls that can be maintained for a given network by imitating the real network on the OPNET simulator. / 0046737675303

No presente trabalho, emprega-se a medida da concentração de etanol do combustível para efetuar correções estequiométricas de maneira direta e instantânea, a fim de eliminar o período necessário para adaptação a partir da medida do sensor de oxigênio (sonda lambda) em eventos de reabastecimento no veículo. Com o objetivo de assegurar a operação flex-fuel, foram empregados métodos para a regulação ar/combustível em malha fechada, realimentados por sensores de oxigênio (banda larga amplificada e banda estreita). O projeto foi implementado em uma ECU (Eletronic Control Unit) idealizada para desenvolvimento de rotinas de programa voltadas ao gerenciamento eletrônico para motores de combustão interna ciclo Otto, denominada Flex-ECU. A ETAS/Bosch Flex-ECU possui programação aplicada à ferramenta ASCET (Advanced Simulation and Control Engineering Tool), o qual trata-se de um código open source para sistemas embarcados de tempo real. Por fim, são exibidos resultados de controle, desempenho e eficiência do motor para diferentes composições de combustível comercializados para a frota de veículos leves em território nacional. Os experimentos revelam a dinâmica de funcionamento do controle A/C bicombustível e discute as suas principais características, com o objetivo de exemplificar métodos de otimização de sua eficiência. / In the present work, the ethanol fuel concentration is used to establish stoichiometric corrections in a direct and instantaneous manner, to eliminate the period necessary for adaptation, from the measurement of the oxygen sensor (lambda probe) in events of refueling. To ensure Flex-fuel operation, closed-loop air/fuel regulation methods were used, fed by oxygen sensors (amplified wide band and narrow band). The project was implemented in an ECU (Electronic Control Unit) designed for the development of code routines for electronic management of an Otto cycle internal combustion engine, labeled Flex-ECU. The ETAS / Bosch Flex-ECU has programming applied to the ASCET (Advanced Simulation and Control Engineering Tool) tool, which is an open source code for real time embedded systems. Finally, results of engine control, performance, and efficiency are presented for different fuel compositions available in Brazil for the fleet of light vehicles. The experiments show the dynamics of the operation of the bi-fuel A/C control and discusses its main characteristics, aiming to exemplify optimization methods of its efficiency.

A thesis which models the DNP3 and IEC 61850 protocol in OPNET / Supervisory Control and Data Acquisition (SCADA) is a critical part of monitoring and controlling of the electrical substation. The aim of this dissertation is to investigate the performance of the Distributed Network Protocol Version 3.3 (DNP3) protocol and to compare its performance to that of International Electro-technical Commission (IEC) 61850 protocol in an electrical substation communication network environment. Building an electrical substation control room and installing the network equipment was going to be expensive and take a lot of time. The better option was to build a model of the electrical substation communication network and run simulations. Riverbend modeller academic edition known as Optimized Network Engineering Tool (OPNET) was chosen as a software package to model substation communication network, DNP3 protocol and IEC 61850 Protocol stack. Modelling the IEC 61850 protocol stack on OPNET involved building the used Open System Interconnection (OSI) layers of the IEC 61850 protocol stack onto the application definitions of OPNET. The Transmission Control Protocol/Internet Protocol (TCP/IP) configuration settings of DNP3 protocol were also modelled on the OPNET application definitions. The aim is to compare the two protocols and determine which protocol is the best performing one in terms of throughput, data delay and latency. The substation communication model consists of 10 ethernet nodes which simulate protection Intelligent Electronic Devices (IEDs), 13 ethernet switches, a server which simulates the substation Remote Terminal Unit (RTU) and the DNP3 Protocol over TCP/IP simulated on the model. DNP3 is a protocol that can be used in a power utility computer network to provide communication service for the grid components. DNP3 protocol is currently used at Eskom as the communication protocol because it is widely used by equipment vendors in the energy sector. DNP3 protocol will be modelled before being compared to the new recent robust protocol IEC 61850 in the same model and determine which protocol is the best for Eskom on the network of the power grid. The network load and packet delay parameters were sampled when 10%, 50%, 90% and 100% of devices are online. The IEC 61850 protocol model has three scenarios and they are normal operation of a Substation, maintenance in a Substation and Buszone operation at a Substation. In these scenarios packet end to end delay of Generic Object Oriented Substation Event (GOOSE), vi © University of South Africa 2020 Generic Substation Status Event (GSSE), Sampled Values (SV) and Manufacturing Messaging Specification (MMS) messages are monitored. The throughput from the IED under maintenance and the throughput at the Substation RTU end is monitored in the model. Analysis of the results of the DNP3 protocol simulation showed that with an increase in number of nodes there was an increase in packet delay as well as the network load. The load on the network should be taken into consideration when designing a substation communication network that requires a quick response such as a smart gird. GOOSE, GSSE, SV results on the IEC 61850 model met all the requirements of the IEC 61850 standard and the MMS did not meet all the requirements of the IEC standard. The design of the substation communication network using IEC 61850 will assist when trying to predict the behavior of the network with regards to this specific protocol during maintenance and when there are faults in the communication network or IED’s. After the simulation of the DNP3 protocol and the IEC 61850 the throughput of DNP3 protocol was determined to be in the range (20 – 450) kbps and the throughput of IEC61850 protocol was determined to be in the range (1.6 – 16) Mbps. / College of Engineering, Science and Technology / M. Tech. (Electrical Engineering)