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År 2020 formulerade lastbilsproducenten Scania CV AB ett mål kring att minska sin energi-förbrukning med 25% till år 2025, med energiförbrukningen för år 2020 som baslinje. Effektiviseringen är nödvändig för att lastbilsproducenten ska kunna fortsätta bedriva ett hållbart och ansvarsfullt företagande. Denna studie utförs hos produktionsenheten DI (drivline-injektor), enheten tillverkar bränsleinsprutningssystem för verksamheten Cummins-Scania XPI Manufacturing. Syftet med arbetet är att identifiera energibesparingsaktiviteter samt föreslå eventuella energibesparingsåtgärder för att kunna stödja produktionsenheten DI med att nå energireduceringsmålet på 25%. En implementationsplan formuleras i syfte att presentera tidslinjen för åtgärdsförslagen. Metoden som tillämpas för att identifiera aktiviteterna är främst litteraturstudier. Dessa kompletteras med empiriska studier som utförs i syfte att tillhandahålla information om produktionsanläggningen. Energikonsumtionen i ursprungsläget samt energikonsumtion efter implementerad åtgärd beräknas för samtliga åtgärdsförslag. Åtgärderna som föreslås för att produktionsenheten ska reducera sin energiförbrukning är följande: • Införa helg- och kvällsavstängningar på maskiner• Införa helg- och kvällsänkningar (viloläge) på maskiner• Byta belysning till LED• Sänka temperatur till följd av implementation av LED-lysrör• Byta till filter med lägre tryckfall• Åtgärda tryckluftsläckage med förebyggande underhåll Implementeringen av följande åtgärder resulterar till en total energibesparing på 228,8 MWh per år. / The year 2020 the truck manufacturer Scania CV AB established a goal of reducing its energy consumption by 25% by 2025, with the year 2020 as its starting point. Reduction of energy consumption is necessary for the truck manufacturer in order to continue to conduct both sustainable as well as responsible business. This study is performed at the production unit DI (driveline-injector), the unit manufactures fuel injection systems for the company Cummins-Scania XPI Manufacturing. The purpose of the report is to identify energy saving activities, and additionally propose energy saving actions to be able to support the production unit DI in achieving the energy reduction target of 25%. A supplementary implementation plan is formulated in order to display the timeline for the presented activities. The method applied to formulate the activities is mainly literature studies from digital scientific publishing systems. Furthermore, are empirical studies performed in order to provide information from the facility. Calculations are performed to identify and present the results of the current energy consumption as well as the energy calculations after the proposed activities. The measures the field study presents for the production unit to reduce its energy consumption result in the following: • Introduce weekend and evening shutdowns on machines• Introduce standby mode on machines• Replace lighting with LEDs• Lower the temperature as a result of implemented LEDs• Switch to filters with lower pressure drop• Implement preventative maintenance in order to reduce compressed air leakage The implementation of the following measures results in a total energy saving of 228.8 MWh per year.

The IoT-embedded smart homes have a high level of home automation and could change many aspects of the residents' daily lives, such as control, convenience, comfort, and energy-saving. The rise of voice-based virtual assistants like Amazon's Alexa, Google assistants in the past five years has brought new potentials to provide occupants with a convenient and intuitive interface to interact with smart homes through conversations. However, the one-way communications in the form of user commands to control building systems does not result in the optimal course of actions. As such, in this thesis, we proposed the concept of proactive smart home assistants and explored the occupants' perception towards smart home assistants proactively providing suggestions to adapt them into energy-saving behaviors. We also investigated the impact of occupants' personal features on their intention in taking energy-saving behaviors. A comprehensive data collection was conducted through online surveys, in which 307 valid responses with participant's personal profile information, their perceptions of smart home assistants, and their feedback to our designed messages were collected. The first manuscript compared participants' responses to traditional plain-text energy-saving suggestions and suggestions provided by smart home assistants. The nudging effect of smart home assistants was justified to be significant in affecting occupant's energy-saving behaviors. Occupant's thermal comfort range, smart home device previous experience, values and beliefs were then proved to have significant impact on their intention in taking the smart home assistant's suggestions. The second manuscript fitted 21 personal characteristics features in machine learning models (SVM, Random Forest, Logistic Regression) to predict occupant's intention and attitude towards energy-saving suggestions. The results indicated that occupant's beliefs about interests in taking actions and beliefs about energy expenses, occupant's education level, residence occupancy type, thermal comfort ranges, and smart home device experiences are important features in occupants' energy-saving behavior intention prediction. This research demonstrates the effect of proactive smart home assistants in human-building interaction as well as the impact of personal characteristic features on occupant's energy-saving behaviors, paving a path to the future development of bi-directional human-building communication. / Master of Science / With the technology development in the fields of the Internet of Things (IoT), smart homes have made it possible to help occupants conserve energy in an efficient way without sacrificing the occupants' comfort. The rise of voice-based virtual assistants like Amazon's Alexa, Google assistants accompany the proliferation of smart speaker products in the past five years has brought new potentials to provide occupants with a convenient and intuitive interface to interact with smart homes through conversations. Based on IoT, the virtual assistants are able to control a broad range of Wi-Fi connected home devices like thermostats, lighting systems, and security systems. As such, through the simple wake words (e.g., "Alexa", "Hey, Google"), occupants can easily control the home environment with their voice commands. Despite the potentials brought by these voice-based virtual assistants, it has been shown that users might not know about all the supported features and limit their interaction with smart home assistants to simple daily tasks. The one-way communications in the form of user commands to control building systems do not result in the optimal course of actions. Therefore, in this study, we have envisioned that these virtual assistants, coupled with their corresponding smart home ecosystems could act proactively as a bridge to facilitate human-building interaction and achieve goals like nudging occupants to adopt sustainable and healthy behaviors. A comprehensive data collection was conducted through online surveys, in which 307 valid responses with participant's personal profile information, their perceptions of smart home assistants, and their feedback to our designed messages were collected. The first manuscript compared participants' responses to traditional plain-text energy-saving suggestions and suggestions provided by smart home assistants. The nudging effect of smart home assistants was justified to be significant in affecting occupant's energy-saving behaviors. Occupant's thermal comfort range, smart home device previous experience, values and beliefs were then proved to have significant impact on their intention in taking the smart home assistant's suggestions. The second manuscript fitted 21 personal characteristics features in machine learning models (SVM, Random Forest, Logistic Regression) to predict occupant's intention and attitude towards energy-saving suggestions. The results indicated that occupant's beliefs about interests in taking actions and beliefs about energy expenses, occupant's education level, residence occupancy type, thermal comfort ranges, and smart home device experiences are important features in occupants' energy-saving behavior intention prediction. This research demonstrates the effect of proactive smart home assistants in human-building interaction as well as the impact of personal characteristic features on occupant's energy-saving behaviors, paving a path to the future development of bi-directional human-building communication.

Existen muchos trabajos relacionados con el diseño y desarrollo de nodos sensores, donde se presentan gran variedad de aplicaciones. Las redes de sensores inalámbricos pueden facilitarnos y mejorar algunos aspectos de nuestra vida diaria. Es fácil, pensar que si este tipo de dispositivo es tan beneficioso para nosotros y para el entorno donde vivimos, su precio debería ser relativamente barato. Pero podemos comprobar que esto no es así. ¿Por qué estos dispositivos son tan caros? ¿Sería posible desarrollar dispositivos con las mismas capacidades y precios más económicos? ¿Cómo puedo fabricar mis nodos sensores de bajo coste? Esta tesis responde a estas preguntas y muestra algunas de las muchas aplicaciones que los nodos sensores pueden tener. En esta tesis hemos propuesto (e implementado en algunos casos) el desarrollo de nodos sensores para la monitorización del medio, a partir de dispositivos de bajo coste. Para la implementación de un nodo sensor, y en definitiva la red que une a todos estos nodos, es importante conocer el medio donde trabajarán. A lo largo de este documento se presentan las investigaciones llevadas a cabo para el desarrollo de sensores en tres ámbitos de aplicación. En el primero de ellos, se desarrollan dispositivos multisenores para la monitorización del medio. La aplicación de las redes de sensores inalámbricas al medio natural, precisa un estudio de cómo se ven afectadas las señales, en función de la distancia, vegetación, humedad del ambiente, etc. Focalizamos nuestros desarrollos en la verificación de incendios en zonas rurales y en el control de plagas en viñedos donde la detección precoz de estos eventos genera elevados ahorros económicos. También proponemos el desarrollo de una red de collares sensores para ganado domestico, que nos ayudará a reducir y prevenir en muchos casos, los ataques de lobos y hurtos de crías. Por último, dentro de este grupo, presentamos una red permite detectar anomalía de los materiales en edificios y red de sensores que nos permite monitorizar las personas mayores o deficientes, que se mueven junto con un grupo, en una excursión o actividad. El segundo grupo de aplicaciones, hace referencia a la monitorización de espacios en entornos de interior. Para ello hemos analizado el comportamiento de las señales inalámbricas en diferentes escenarios. Los resultados, nos han permitido extraer un nuevo método de diseño de las redes inalámbricas en interiores. Nuestro método, permite definir la mejor ubicación de los dispositivos de red y nodos sensores en interiores con un ahorro en el número de sensores del 15%. Por último, se presenta el estudio sobre las comunicaciones subacuáticas basadas en las ondas electromagnéticas donde analizamos la dependencia de las comunicaciones subacuáticas en agua dulce en función de la frecuencia, temperatura, tasas de transferencia de datos y modulación. Relacionado con el medio subacuático, presentamos 2 propuestas. La primera de ellas hace referencia a la implementación de una red de sensores para granjas marinas que nos permite reducir la cantidad de residuos depositados en el lecho marino y reducir el porcentaje de comida desperdiciada. La segunda propuesta es el desarrollo de dos sensores oceanográficos que nos permitirían controlar la cantidad de comida y heces depositadas en el suelo y controlar la turbidez del agua de manera muy simple y económica Todos estos desarrollos y propuestas, han estado precedidos por un exhaustivo estudio sobre los problemas energéticos que las redes de sensores inalámbricas presentan y las técnicas que pueden emplearse, para prolongar la vida útil de la red y mejorar su estabilidad. / There are many works related to the design and development of sensor nodes which present several applications. Wireless sensor networks can facilitate and improve some aspects of our daily lives. It is easy to think that if this type of device is so beneficial to us and to our environment, its price should be relatively cheap. But we can see that this is not true. Why these devices are so expensive? Would it be possible to develop devices with the same capabilities and lower prices? How can I make my low-cost sensor nodes? This dissertation answers these questions and shows some of the many applications that sensor nodes may have. In this dissertation, we propose (and implement in some cases) the development of sensor nodes for environmental monitoring, from low-cost devices. For the implementation of a sensor node and network which joins all these nodes, it is important to know the environment where they will work. Throughout this dissertation, we present the research carried out for the development of sensors in three main application areas. In the first of these areas, we present multisensor devices developed for environmental monitoring. The application of wireless sensor networks to the environment requires a study of how signals are affected depending on the distance, vegetation, ambient humidity, etc. We focus our developments on the fire detection in rural areas and on the control of pests in vineyards where the early detection of these events generates high economic savings. We also propose the development of a sensor network which will help us to reduce and prevent wolves¿ attacks and theft in livestock. Finally, within this group, we present a network to detect material anomalies in building and a sensor network which allows us to monitor the elderly or disabled people who move along with a group on a tour or activity. The second group of applications is related to the monitoring of spaces in indoor environments. For this, we analyze the behavior of wireless signals in different scenarios. These results allowed us to extract a new method for designing wireless networks in indoor environments. Our method allows defining the best location of network devices and sensor nodes indoors saving 15% of the sensors needed. Finally, we present a study on underwater freshwater communications based on electromagnetic waves, where we analyze the dependency of underwater communications as a function of working frequency, temperature, data transfer rates and modulation. Related to underwater environment, we present two proposals. First one refers to the implementation of a sensor network for marine farms which allows us to reduce the amount of waste deposited on the seabed and reduce the percentage of wasted food. The second proposal is the development of two oceanographic sensors which allow us to control the amount of food and feces deposited in seabed and the water turbidity control in a very simple and inexpensive way. All these developments and proposals have been preceded by a comprehensive study on the energy problems in wireless sensor networks. We have also presented several techniques which can be used to prolong the network lifetime and improve its stability. / Sendra Compte, S. (2013). Deployment of Efficient Wireless Sensor Nodes for Monitoring in Rural, Indoor and Underwater Environments [Tesis doctoral]. Editorial Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/32279

The study presents a numerical investigation about the hydrodynamic characteristics of a transom mounted interceptor on the Oliver Hazard Perry class frigate (FFG-7), in order to assess the potential of propulsion power reduction in a wide range of speeds. This study is aimed to design a stern interceptor with optimal efficiency not only at top speed, but also cruising/transfer speeds, by a simple regulation of its variable geometrical characteristics (from a construction and operational standpoint). A high fidelity numerical model is developed in the open source CFD suite OpenFOAM for the prediction of the longitudinal dynamic equilibrium at speed and the total resistance characteristics of the bare hull. The Reynolds Averaged Navier-Stokes Equations are solved using interDyMFoam, a multiphase volume of fluid solver which allows for a dynamic mesh. The numerical model is validated using the results of the experimental model tests conducted on a 1/80th scale model at the United States Naval Academy Hydromechanics Laboratory (NAHL). The validated numerical model is used to predict the hydrodynamic characteristics of the transom mounted interceptor at different interceptor settings and speeds. The results show that the interceptor reduces the amount of resistance, the running trim, and the sinkage of the ship at high speeds. For a speed of 0.392 Froude number (Fr), a drag reduction of 3.76% was observed, as well as a significant reduction in trim. / Master of Science / The drag acting on the hull is an important component that has to be considered during the process of designing the ship. An interceptor is a device that has been developed to improve the performance of hulls by reducing the drag. This research studies the influence of the interceptor on the resistance and motion of the ship across a range of speeds. The geometrical characteristics of the interceptor are varied in order to identify the geometry that would provide optimal performance across the speed range tested. This study is conducted using the Computational Fluid Dynamics (CFD) software OpenFOAM as well as model tests that were conducted on a 1/80th scale model.

The dissertation consists of four self-contained essays on consumption. Essays 1 and 2 consider different measures of aggregate consumption, and Essays 3 and 4 consider how the distributions of income and wealth affect consumption from a macro and micro perspective, respectively. Essay 1 considers the empirical practice of seemingly interchangeable use of two measures of consumption; total consumption expenditure and consumption expenditure on nondurable goods and services. Using data from Sweden and the US in an error correction model, it is shown that consumption functions based on the two measures exhibit significant differences in several aspects of econometric modelling. Essay 2, coauthored with Thomas Holgersson, considers derivation of a univariate and a multivariate version of a test for asymmetry, based on the third central moment. The logic behind the test is that the dependent variable should correspond to the specification of the econometric model; symmetric with linear models and asymmetric with non-linear models. The main result in the empirical application of the test is that orthodox theory seems to be supported for consumption of both nondurable and durable consumption. The consumption of durables shows little deviation from symmetry in the four-country sample, while the consumption of nondurables is shown to be asymmetric in two out of four cases, the UK and the US. Essay 3 departs from the observation that introducing income uncertainty makes the consumption function concave, implying that the distributions of wealth and income are omitted variables in aggregate Euler equations. This implication is tested through estimation of the distributions over time and augmentation of consumption functions, using Swedish data for 1963-2000. The results show that only the dispersion of wealth is significant, the explanation of which is found in the marked changes of the group of households with negative wealth; a group that according to a concave consumption function has the highest marginal propensity to consume. Essay 4 attempts to empirically specify the nature of the alleged concavity of the consumption function. Using grouped household level Swedish data for 1999-2001, it is shown that the marginal propensity to consume out of current resources, i.e. current income and net wealth, is strictly decreasing in current resources and net wealth, but approximately constant in income. Also, an empirical reciprocal to the stylized theoretical consumption function is estimated, and shown to bear a close resemblance to the theoretical version.

Thesis (MPhil (Sustainable Development Planning and Management))--University of Stellenbosch, 2004.

Thesis (MBA (Business Management))--University of Stellenbosch, 2009. / ENGLISH ABSTRACT: High levels of gross national savings reduce a country’s reliance and exposure to the vagaries of the global capital market. On an individual level, delaying consumption and providing for future needs and prosperity is a necessary condition to improve or maintain the quality of life. India and China’s gross national savings and, in particular, their household savings rates are higher than those of South Africa. Within the context of sustaining the global competitiveness of these developing countries - each with a burgeoning middle class – there is a need to ensure that policy formulation recognises the consumption and savings needs of this segment of the population. With a view to understanding the reasons why the household savings rates of China and India are so high in comparison to South Africa, this report investigates whether (and to what extent) South African policy makers can learn from China and India in the design of its policy framework to reduce consumption and create a savings culture. This research project is a comparative analysis of the determinants of household savings behaviour in China, India and South Africa, with specific reference to the consumer behaviour of the middle class consumer in each country. The comparative analysis draws on secondary sources such as journal articles, books, completed research and the Internet. While India and China have high household savings rates, this is not as a function of policy reforms that were introduced to encourage saving. Rather, an absence of sufficient financial sector development and a weak social safety net, coupled with a collective household culture and attitude that values saving ahead of consumption, that has resulted in households in India and China, and in particular middle income households, saving to ensure adequate provision is made. In South Africa, the impacts of financial liberalisation and a flawed social security system have resulted in a failure to provide broad based income protection. Increased consumer access to financial services coupled with a coherent social security structure and continued government investment are critical threads that must pervade the reform agenda in South Africa. / AFRIKAANSE OPSOMMING: Hoë bruto nasionale spaarvlakke verminder ’n land se afhanklikheid van en blootstelling aan die wisselvalligheid van die internasionale kapitaalmark. Op ’n individuele vlak is die uitstel van verbruiksbesteding en voorsiening vir toekomstige behoeftes en voorspoed ’n voorvereiste vir die verbetering of handhawing van lewenspeil. Indië en China se bruto nasionale spaarvlakke, en in die besonder hul huishoudelike spaarkoerse, is hoër as dié van Suid-Afrika. Binne die konteks van die volhoubare wêreldwye mededingendheid van hierdie ontwikkelende lande – elk met ’n ontluikende middelklas – is daar ’n behoefte om te verseker dat beleidsformulering die verbruiks- en spaarbehoeftes van hierdie segment van die bevolking erken. Om te probeer verstaan waarom die huishoudelike spaarkoerse in China en Indië so hoog is in vergelyking met Suid-Afrika, ondersoek hierdie verslag of (in en watter mate) Suid-Afrikaanse beleidvormers by China en Indië kan gaan kers opsteek ten opsigte van die ontwerp van sy beleidsraamwerk om verbruik te verminder en ’n spaarkultuur te skep. Hierdie navorsingsprojek is ’n vergelykende ontleding van die bepalende faktore van huishoudelike spaargedrag in China, Indië en Suid-Afrika, met spesifieke verwysing na die verbruikersgedrag van die middelklas verbruiker in elke land. Die vergelykende ontleding gebruik sekondêre bronne soos joernaalartikels, boeke, voltooide navorsing en die internet. Hoewel Indië en China hoë huishoudelike spaarkoerse het, is dit nie ’n regstreekse uitvloeisel van beleidshervormings wat ingestel is om spaar aan te moedig nie. Dit is eerder ’n gebrek aan voldoende finansiële sektorontwikkeling en ’n swak maatskaplike veiligheidsnet, tesame met ’n kollektiewe huishoudelike kultuur en ingesteldheid wat groter waarde aan spaar heg as aan verbruik, wat daartoe gelei het dat huishoudings in Indië en China, en veral middelklas huishoudings, spaar om genoegsame voorsiening te verseker. In Suid- Afrika het die impak van finansiële bevryding en ’n gebrekkige maatskaplike welsynstelsel gelei tot ’n onvermoë om breedgebaseerde inkomstebeskerming te verskaf. Groter verbruikerstoegang tot finansiële dienste, tesame met ’n samehangende maatskaplike welsynstruktuur en volgehoue staatsinvestering, is kritieke temas wat die hervormingsagenda in Suid-Afrika moet deurvleg.

Thesis (MDF)--Stellenbosch University, 2015. / ENGLISH ABSTRACT: This study is on the impact of cooperative societies on capital formation using a case study of selected cooperatives in Kwazulu Natal province of South Africa. The study is a novel empirical investigation in that focuses on impact of cooperative societies financing on members and how that may translate into significant increase in household incomes. The study assess and evaluates the roles played by cooperative societies’ financing and loans services on members’ economic condition particular their business expansion, profitability and later on improvements in household incomes. Using focus group discussion and questionnaire, the study uncovers the activities of cooperative societies located in both urban and rural communities within KZN Province. The study provides some evidence on the importance of leaving conditions after member access to cheap and affordable loans and provides some insights into the development of rural businesses, how complex they are, and how they require more input than just the financing received through cooperative loans as a final end. It also breaks new ground in informal cooperative operations, community improvement and rural finance research by providing a peculiarity between standard of living and quality of life variables in measuring and determining the economic condition of rural livelihoods and the production of circle of New Institutional Economics theory that the role of cooperatives to the members involve financial capital, physical capital and social capital which are interrelated. This serves to properly distinguish and appropriately identify the roles of cooperative societies in rural finance to increase in household income, ownership of assets and acquisition of enterprise assets. However, the study reveals that access to funds and participation in the cooperative does not lead to enterprise profitability, thus less capital accumulation while rural financial needs are more accessible from cooperatives than other sources. From its findings, this study identified and discussed potential areas for the improvement of cooperative societies that could be of benefit to any urban and rural finance providers and the cooperative members.