This paper is presenting the application of Power Regenerative Boom(PRB) system to excavator. In order to increase the fuel efficiency of the excavator, potential energy of the front structure is recuperated by the hydraulic hybrid system with electric-hydraulic control, during boom down motion. Charged energy into accumulator is reused after boom down motion, the pressurized oil goes to hydraulic motor. The hydraulic motor is mounted on the engine PTO(Power Take-Off), therefore output torque of the hydraulic motor assists the diesel engine directy, it leads to decrease fuel consumption of diesel engine. After the system design and simulation investigation, the presented system was installed into Doosan’s 38ton excavator, DX380LC-3 model, and the energy saving result was verified by a digging and dumping repetition test. The test result shows that fuel consumption was dramatically decreased by 5.0 L/hr compared to the standard DX380LC-3.

[pt] Um dos principais desafios em redes de sensores sem fio (RSSF) é reduzir o consumo de energia dos nós sensores. Um método usado para economizar a bateria que alimenta os nós sensores é o duty cycling (DC) do rádio, onde o rádio fica desligado na maior parte do tempo e fica ligado por pouco tempo para verificar se existe alguma mensagem. O DC é usado com frequência em aplicações de monitoramento onde apenas uma mensagem é transmitida depois da leitura do sensor. Geralmente a leitura do sensor só volta a acontecer depois de minutos, logo poucas mensagens são transmitidas por unidade de tempo. Neste trabalho, analisamos o uso da técnica de DC em um contexto diferente, o da disseminação de código, onde várias mensagens são enviadas em um curto espaço de tempo, e que usa mensagens broadcast, ao contrário do monitoramento, que utiliza mensagens unicast. Analisamos dois algoritmos de disseminação específicos, um para um ambiente de máquinas virtuais executando nos motes, onde o código disseminado é um script com tamanho da ordem de bytes, e outro para disseminação de códigos da aplicação inteira, onde o tamanho é bem maior que no caso do script, da ordem de kbytes. O objetivo deste trabalho foi avaliar qual o impacto do DC na latência e quanto de energia foi economizado quando comparado a deixar o rádio ligado o tempo todo, que é como ambos algoritmos funcionam em sua forma original. / [en] One of the key challenges in wireless sensor networks (WSN) is to save energy at motes. One method to save battery is radio duty cycling (DC), which keeps the radio turned off in most of the time and turns the radio on for a short time to verify if any there are any messages. DC is frequently used in monitoring applications where only one message is transmitted after the mote reads its sensor. Usually the mote reads its sensor only once every few minutes, so few unicast messages are transmitted in the network per time unit. This work analyzes the use of the DC method in code dissemination. In this context, multiple broadcast messages are transmitted in a short time. We examined two specific dissemination algorithms, one of them proposed for a virtual machine environment, in which the disseminated code is a small script, and a second one originally proposed for disseminating the code of an entire application, typically much larger than a script. The objective of this study is to evaluate the impact of DC on latency and how much energy was saved when compared to leaving the radio on all the time, which is how both algorithms work in their original form.

Today companies (especially large companies whose employees make a lot of international business trips) often have very large telephone bills. While international roaming technically works with GSM, the cost of phone calls from one country to another are often much higher than calls within a country. Despite political pressure to reduce the costs of roaming within the European Union, the cost of phone calls from one country to another are often quite expensive. A cost-saving solution is eagerly desired by many firms. OptiCall Solutions AB has designed an integrated system called the Dial over Data (DoD) solution. In this scheme, a caller sends a data request to the DoD server instead of directly making a call to the party that they wish to speak with. The DoD solution uses an Internet Protocol Private Branch Exchange (IP-PBX) to make two Session Initiation Protocol (SIP) calls, one to the caller and another to the callee, then bridges these two calls. To realize cost savings, the cost of these two calls and the cost of the infrastructure necessary to make the two calls and to bridge them must be lower than the cost of the direct call. Call Through is a service for making cheap international calls which is provided by many telecommunications companies. Instead of making a direct call to the party the caller wants to speak with, the caller makes a call to the local call-through service access number. The caller dials the actual callee’s number after the call is established. The service provider then makes a call to the callee and bridges the two calls. The caller only needs to pay for a local call and the service subscription fee, rather than the expensive international call fee. This can greatly reduce the costs for user who need to make a lot international calls. Today, many companies use such a call-through service in order to reduce the total cost of their employees’ calls. Additionally, the Mobile Extension (MEX) is a concept which gives mobile users the ability to use their mobile phone in the same manner as their fixed office phone, for example, by providing services such as setting presence and transferring a call. In addition, the user should experience a consistent interface, for example the calling number displayed for the callee should always be a number that the callee could use to return the call. In this thesis project, a mobile extension application called ‘OptiCaller’ based on the Symbian OS was developed and evaluated. This application is part of the DoD solution and provides client side functionality. Furthermore, it supports making call-through calls and using the MEX functions. Additionally, it is designed and implemented in a flexible way so that it can work with a variety of different PBX solutions. A provisioning system called ‘OptiCaller Provisioning System’ was also designed and evaluated. This provisioning system was tailored for the ‘OptiCaller’. It provides administrators a platform to manage the OptiCaller application on the end-users’ mobile phones. / Idag har företag (i synnerhet stora företag vars anställda gör en hel del internationella affärsresor) ofta mycket stora telefonräkningar. Även om internationell roaming fungerar tekniskt i GSM så är kostnaden för telefonsamtal från ett land till ett annat ofta mycket högre än samtal inom ett land. Trots politiska påtryckningar för att minska roamingkostnaderna inom EU, så är kostnader för telefonsamtal från ett land till ett annat ofta ganska dyra. En lösning som kan minska dessa kostnader välkomnas av många företag. OptiCall Solutions AB har utvecklat ett integrerat system som kallas Dial över Data (DoD). I detta system skickas först en samtalsbegäran från en klient till en server istället för att klienten direkt ringer ett samtal till den som de vill tala med. DoD systemet använder Internet Protocol Private Branch Exchange (IP-PBX) för att göra två Session Initiation Protocol (SIP) samtal, en till den som ringer och en den uppringda parten. Sedan kopplas dessa två samtal ihop. Värt att beakta är att kostnaden för denna infrastruktur samt att producera två samtal i stället för ett bör vara lägre än kostnaden för ett direkt samtal. Samtalskort är en tjänst för att göra billiga internationella samtal vilket erbjuds av flera telekommunikationsföretag. Istället för att göra ett direkt samtal till den som den uppringande vill tala med, gör först ett samtal till den lokala call-service noden. Med hjälp av en transparent klient så behöver användaren inte själv ringa call-service noden utan det sker helt automatik. Väl besvarat av call-service noden så kopplas samtalet till den destination användaren vill ringa till. Den som ringer behöver bara betala för ett lokalsamtal och tjänstens prenumerationsavgift. Detta kan kraftigt minska kostnaderna för användare som gör en hel del utlandssamtal. Idag är det även många företag som tillhandahåller en sådan funktion till sina anställda för att minska den totala kostnaden för deras samtal. Mobile Extension (MEX) är ett begrepp som ger mobila användare möjlighet att använda sin mobiltelefon på samma sätt som sina fasta kontorstelefon, till exempel genom att tillhandahålla tjänster såsom inställningen närvarostatus och koppling ett samtal. Användaren bör uppleva ett konsekvent gränssnitt, till exempel att det uppringande numret som visas alltid bör kunna användas för att ringa tillbaka till den som ringt. I detta examensarbete har en så kallad mobil anknytning tillämpning "OptiCaller", baserad på Symbian OS, utvecklats och utvärderats. Denna applikation är en del av DoD lösningen och ger funktionalitet på klientsidan. Den har även stöd för samtalskortfunktioner och MEX funktioner. Den är dessutom utformad på ett flexibelt sätt så att den kan arbeta med en rad olika PBX lösningar. Ett system för provisionering anpassat för OptiCaller kallat ”OptiCaller Provisioning System" har också framtagits och utvärderats. Det ger administratören en plattform för att administrera OptiCaller klienter i en större skala och hanterar såväl installation samt inställningar av OptiCaller klienter på mobiltelefoner.

The current interest in energy saving asphalt production techniques is great and several new processes have been developed to reduce the mixing and compaction temperatures for hot mix asphalt. In particular, mastic asphalt products (Gussasphalt) require high working temperatures, and harder requirements concerning bitumen fumes and carbon dioxide emissions have been introduced for such products. Consequently, the need of a new means of producing and placing mastic asphalt at lower temperatures is particularly large. One way of reducing asphalt mixture temperature is by using special flow improving additives like wax. This technique has successively been tried in several studies for polymer modified mastic asphalt used for bridge decks and parking areas in Sweden. However, there still are uncertainties about possible negative impact on crack susceptibility at lower temperatures due to the addition of wax. In this study, 4% montan wax (Asphaltan A) was used for one particular polymer modified mastic asphalt product. Type and amount of wax additive was selected based on results from earlier studies. The impact on binder, binder/filler mixtures and mastic asphalt from production was tested in the laboratory, focusing on low temperature performance. The bending beam rheometer (BBR) was used for determining low temperature creep compliance and the tensile stress restrained specimen test (TSRST) for determining fracture temperatures. Binder properties were determined using dynamic mechanical analysis (DMA), Fourier transform infrared (FTIR) spectroscopy and conventional tests (softening point, penetration, elastic recovery, Fraass breaking point, viscosity and storage stability). Aging was performed using the rolling thin film oven test (RTFOT) at 200°C. As expected, the addition of wax to the polymer modified binder showed a viscosity reduction at higher temperatures, corresponding to a similar positive effect of more than 10°C on production and laying temperature for the mastic asphalt. DMA and BBR results showed some increase in stiffness and a more elastic response of the wax modified binder at medium and low temperatures. The TSRST fracture temperature was 5 °C higher for the mastic asphalt containing 4% wax, indicating however no dramatic negative impact on crack susceptibility.

As the energy price goes up, more and more concern has been focused on the sustainable development of residential houses. One of the best solution will be the low energy housing-passive house. The concept of passive house has been popular in Germany and whole Europe in the last 10 years, however, there is no official residential passive house standard project in China now. In this thesis, the feasibility of developing passive house in China will be analysed. Combined with the mature experience from the passive house project in Europe, a Chinese way of building the passive house will be provided. According to the previous studies, a lot of knowledge of passive house projects in Sweden have been referred to help doing the analysis about the passive house development in China. Due to the fact that there is no passive house had done before in China, the some assumptions have been made to help with the economy analysis. It is assumed that one passive house residential project will be built in Shenyang city, Liaoning Province. After the analysing and calculating, it can be concluded that it is possible and profitable to develop the passive house standard residential projects in China. It has a bright future.

A Research Report submitted in partial fulfilment of the Degree of Master of Commerce (Economics/Economic Science) in the School of Economic and Business Sciences, University of the Witwatersrand, September 2018 / This study investigates the determinants of household savings in South Africa using panel data estimation techniques and National Income Dynamics Study (NIDS) data for the period 2008-2015. Results show that household savings habits in South Africa are strongly driven by sociodemographic factors such as income, relative income, asset ownership and white population group representation. Whereas household size, home ownership, household expenditure and black population group representation remain plausible arguments for household dissaving in South Africa. To some extent, these findings imply that strategies to increase household savings in South Africa should improve the distribution of income and employment among the population. There is also a need for an in-depth analysis as to why and how the country’s black population can be encouraged to improve on household savings. / XL2019

Legislation, economic incentives and informational campaigns are traditional tools of government used to exert its influence on citizens. More recently, other behavioral interventions called nudges and boosts have also come into usage to influence behavior. Nudges exploit faults in human decision making, pushing the individual in a direction of a specific choice, hence the name nudge. Boosts instead try to foster existing competences in the individual, effectivizing decision making while still preserving the individual’s own agency. Both nudges and boosts have proved to be cost-effective ways of influencing behavior, making them attractive alternatives to traditional behavioral interventions. An a priori way to investigate the effectiveness of behavioral interventions without their implementation is by measuring their acceptance. This thesis investigates the acceptance for nudges and boosts compared to traditional behavioral interventions when used in the domain of energy saving practices. The results show that acceptance differs greatly depending on which behavioral intervention is used, which energy saving domain the behavioral intervention is applied to, and to an extent the demographic characteristics of the individuals exposed to the behavioral intervention.

<p>Most of the heavy-duty machines, in particular construction vehicles, employ hydraulically actuated functions that are used to perform multiple tasks with elevated power requirements. Such high-power demand motivates the Original Equipment Manufacturers (OEMs) to minimize the costs associated with energy consumption through the design of such hydraulic systems. The human-machine interaction (human factors) and the efficiency of the hydraulic control system are considered key elements towards a successful design. The interaction between the operator and the machine considerably affects the performance of construction machines. In order to maintain high levels of productivity, the operators require comfort and effortless controllability of the multiple hydraulic functions. The comfort requirement can include limited shocks and oscillations while operating the machines (while driving and controlling the implement motion), cabin accessories (AC, radio, cameras, etc.) and accessibility to the instrumentation. Besides, the operators have to control multiple functions simultaneously in an efficient manner while maintaining high levels of productivity. Consequently, the operators require smooth controllability of such functions. Such demand can largely affect the efficiency of the expected hydraulic control system and can induce additional costs and complexity. The OEMs are therefore forced to find a balance between efficiency and operators’ requirements to be competitive on the market. As a result, the currently adopted hydraulic architectures rely on purely hydraulic components to ensure robustness and functionality of the hydraulic functions at the expenses of limited performance and high-power consumption. In this dissertation, electro-hydraulic components are employed to induce improvements of the commercially available solutions while still complying with the operators’ demands and energy efficiency. To this end, this work tackles the weaknesses of traditional hydraulic architectures and it proposes alternative solutions to overcome their limitations. Two full-size wheel loaders are used to study the behavior of the existing system and later to implement the proposed variations. First, the development of an innovative ride control feature to improve the operators’ comfort is presented. Experimental results show the proposed strategy having better comfort performances compared to the purely hydraulic solution. Besides, the electro-hydraulic alternative does not demand the costly additional components the commercial solution instead requires. Second, this work faces the concern for efficiency of the present hydraulic architecture. The most diffused hydraulic system for the studied category of construction machines, commonly known as Load Sensing (LS), is sized to work most efficiently for elevated power conditions. During this work, an electronically controlled hydraulic supply unit and a flow-sharing method are used to reduce the hydraulic power consumption in the regions where the traditional LS system is less efficient. With a simple and cost-effective modification, the presented control strategy can induce an efficiency improvement over a wide range of operating conditions. Third, this dissertation proposes an operator-assistance feature to potentially increase the overall productivity and reduce the operator’s stress. An online estimation algorithm was developed to predict the payload weight of the transported material inside the bucket and the pushing forces during a typical loading cycle. The calculated payload mass provides an estimate of the user’s productivity level and it is extremely advantageous when the loaded material should reach a certain target weight. The developed estimation algorithm can also support an optimized autonomous excavation process, which can progressively limit the operator-machine interaction.</p>

Ce travail de thèse traite différents aspects de la conception basse consommation. Tout d’abord, le concept du calcul réversible, considéré comme le premier essai pour un calcul sans dissipation, est présenté. Puis, je me suis intéressée aux dissipations des circuits complémentaires MOS puisque c’est la logique la plus couramment utilisée dans les circuits numériques. J’ai proposé deux approches pour réduire la consommation de ces circuits numériques. La première approche porte sur la réduction de la dissipation due aux glitchs. J’ai proposé une nouvelle méthode qui consiste à adapter les tensions de seuil des transistors pour assurer un filtrage optimal de ces glitchs. Les résultats de simulation montrent que nous obtenons jusqu’à16% de réduction des glitchs, ce qui représente une amélioration de 18% par rapport à l’état de l’art sur la base des circuits de référence ISCAS85. La deuxième approche porte sur la réduction de la dissipation obtenue en faisant fonctionner les transistors MOS en régime d’ inversion faible (sous-seuil). Les circuits fonctionnant dans ce régime représentent une solution idéale pour les applications ultra-basse-consommation. Par contre, l’une des préoccupations majeures est qu’ils sont plus sensibles aux dispersions des processus de fabrication, ce qui peut entraîner des problèmes de fiabilité. Je propose un modèle compact qui détermine le point d’énergie minimum de façon analytique, donc sans recourir à une simulation type SPICE, tout en étant suffisamment précise vis-à-vis de la variabilité(due à la dispersion). L’écart de résultat entre le modèle compact et un modèle SPICE complet est de 6%. / This thesis focuses on different aspects of ”Low Energy Design”. First, reversible logic, as it is the first attempt for low energy computing, is briefly dis- cussed. Then, we focus on dynamic energy saving in the combinational part of CMOS circuits. We propose a new method to reduce glitches based on dual threshold voltage technique. Simulation results report more than 16% average glitch reduction. We also show that combining dual-threshold to gate-sizingtechnique is very interesting for glitch filtering as it brings up to 27 % energy savings. In the third part of this dissertation, we have been interested in sub-threshold operation where the minimum energy can be achieved using a reduced supply voltage. Sub-threshold operation has been an efficient solution for energy-constrained applications with low speed requirements. However, it is very sensitive to process variability which can impact the robustness and effective performance of the circuit. We propose a model valid in sub and near threshold regions in order to correctly estimate the circuit performance in a variability aware analysis. We provide an analytical solution for the optimum supply voltage that minimizes the total energy per operation while considering variability effects. Spice simulations matches the analytical result to within 6%.

The American Recovery and Reinvestment Act (ARRA) of 2009 authorized the distribution of about $30 billion incentive funds to accelerate electronic health record (EHR) applications to improve the quality of care, safety, privacy, care coordination, and patients' involvement in healthcare. EHR use has the potential of saving $731 in costs for hospitals per patient admission; however, most hospitals are not applying EHR to reach the level at which cost savings are possible. The purpose of this single case study was to explore strategies that IT leaders in hospitals can use to apply EHR to achieve the cost saving benefits. The participants were IT leaders and EHR super users at a large hospital in Texas with successful experience in applying EHR. Information systems success model formed the conceptual framework for the study. I conducted face-to-face interviews and analyzed organizational documents. I used qualitative textual data analysis method to identify themes. Five themes emerged from this study, which are ensuring information quality, ensuring system quality, assuring service quality, promoting usability, and maximizing net benefits of the EHR system. The findings of this study included four strategies to apply EHR; these strategies include engaging training staff, documenting accurately and in a timely manner, protecting patient data, and enforcing organizational best practice policies to maximize reimbursement and cost savings. The findings of this study could contribute to positive social change for the communities because EHR successful application includes lower cost for hospitals that may lead to the provision of affordable care to more low-income patients.