902 resultados para Interoperable Home Energy Management Systems (HEMS)


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This work is part of a bigger project which aims to research the potential development of commercial opportunities for the re-use of batteries after their use in low carbon vehicles on an electricity grid or microgrid system. There are three main revenue streams (peak load lopping on the distribution Network to allow for network re-enforcement deferral, National Grid primary/ secondary/ high frequency response, customer energy management optimization). These incomes streams are dependent on the grid system being present. However, there is additional opportunity to be gained from also using these batteries to provide UPS backup when the grid is no longer present. Most UPS or ESS on the market use new batteries in conjunction with a two level converter interface. This produces a reliable backup solution in the case of loss of mains power, but may be expensive to implement. This paper introduces a modular multilevel cascade converter (MMCC) based ESS using second-life batteries for use on a grid independent industrial plant without any additional onsite generator as a potentially cheaper alternative. The number of modules has been designed for a given reliability target and these modules could be used to minimize/eliminate the output filter. An appropriate strategy to provide voltage and frequency control in a grid independent system is described and simulated under different disturbance conditions such as load switching, fault conditions or a large motor starting. A comparison of the results from the modular topology against a traditional two level converter is provided to prove similar performance criteria. The proposed ESS and control strategy is an acceptable way of providing backup power in the event of loss of grid. Additional financial benefit to the customer may be obtained by using a second life battery in this way.

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The authors analyse some of the research outcomes achieved during the implementation of the EC GUIDE research project “Creating an European Identity Management Architecture for eGovernment”, as well as their personal experience. The project goals and achievements are however considered in a broader context. The key role of Identity in the Information Society was emphasised, that the research and development in this field is in its initial phase. The scope of research related to Identity, including the one related to Identity Management and Interoperability of Identity Management Systems, is expected to be further extended. The authors analyse the abovementioned issues in the context established by the EC European Interoperability Framework (EIF) as a reference document on interoperability for the Interoperable Delivery of European eGovernment Services to Public Administrations, Business and Citizens (IDABC) Work Programme. This programme aims at supporting the pan-European delivery of electronic government services.

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The modern grid system or the smart grid is likely to be populated with multiple distributed energy sources, e.g. wind power, PV power, Plug-in Electric Vehicle (PEV). It will also include a variety of linear and nonlinear loads. The intermittent nature of renewable energies like PV, wind turbine and increased penetration of Electric Vehicle (EV) makes the stable operation of utility grid system challenging. In order to ensure a stable operation of the utility grid system and to support smart grid functionalities such as, fault ride-through, frequency response, reactive power support, and mitigation of power quality issues, an energy storage system (ESS) could play an important role. A fast acting bidirectional energy storage system which can rapidly provide and absorb power and/or VARs for a sufficient time is a potentially valuable tool to support this functionality. Battery energy storage systems (BESS) are one of a range suitable energy storage system because it can provide and absorb power for sufficient time as well as able to respond reasonably fast. Conventional BESS already exist on the grid system are made up primarily of new batteries. The cost of these batteries can be high which makes most BESS an expensive solution. In order to assist moving towards a low carbon economy and to reduce battery cost this work aims to research the opportunities for the re-use of batteries after their primary use in low and ultra-low carbon vehicles (EV/HEV) on the electricity grid system. This research aims to develop a new generation of second life battery energy storage systems (SLBESS) which could interface to the low/medium voltage network to provide necessary grid support in a reliable and in cost-effective manner. The reliability/performance of these batteries is not clear, but is almost certainly worse than a new battery. Manufacturers indicate that a mixture of gradual degradation and sudden failure are both possible and failure mechanisms are likely to be related to how hard the batteries were driven inside the vehicle. There are several figures from a number of sources including the DECC (Department of Energy and Climate Control) and Arup and Cenex reports indicate anything from 70,000 to 2.6 million electric and hybrid vehicles on the road by 2020. Once the vehicle battery has degraded to around 70-80% of its capacity it is considered to be at the end of its first life application. This leaves capacity available for a second life at a much cheaper cost than a new BESS Assuming a battery capability of around 5-18kWhr (MHEV 5kWh - BEV 18kWh battery) and approximate 10 year life span, this equates to a projection of battery storage capability available for second life of >1GWhrs by 2025. Moreover, each vehicle manufacturer has different specifications for battery chemistry, number and arrangement of battery cells, capacity, voltage, size etc. To enable research and investment in this area and to maximize the remaining life of these batteries, one of the design challenges is to combine these hybrid batteries into a grid-tie converter where their different performance characteristics, and parameter variation can be catered for and a hot swapping mechanism is available so that as a battery ends it second life, it can be replaced without affecting the overall system operation. This integration of either single types of batteries with vastly different performance capability or a hybrid battery system to a grid-tie 3 energy storage system is different to currently existing work on battery energy storage systems (BESS) which deals with a single type of battery with common characteristics. This thesis addresses and solves the power electronic design challenges in integrating second life hybrid batteries into a grid-tie energy storage unit for the first time. This study details a suitable multi-modular power electronic converter and its various switching strategies which can integrate widely different batteries to a grid-tie inverter irrespective of their characteristics, voltage levels and reliability. The proposed converter provides a high efficiency, enhanced control flexibility and has the capability to operate in different operational modes from the input to output. Designing an appropriate control system for this kind of hybrid battery storage system is also important because of the variation of battery types, differences in characteristics and different levels of degradations. This thesis proposes a generalised distributed power sharing strategy based on weighting function aims to optimally use a set of hybrid batteries according to their relative characteristics while providing the necessary grid support by distributing the power between the batteries. The strategy is adaptive in nature and varies as the individual battery characteristics change in real time as a result of degradation for example. A suitable bidirectional distributed control strategy or a module independent control technique has been developed corresponding to each mode of operation of the proposed modular converter. Stability is an important consideration in control of all power converters and as such this thesis investigates the control stability of the multi-modular converter in detailed. Many controllers use PI/PID based techniques with fixed control parameters. However, this is not found to be suitable from a stability point-of-view. Issues of control stability using this controller type under one of the operating modes has led to the development of an alternative adaptive and nonlinear Lyapunov based control for the modular power converter. Finally, a detailed simulation and experimental validation of the proposed power converter operation, power sharing strategy, proposed control structures and control stability issue have been undertaken using a grid connected laboratory based multi-modular hybrid battery energy storage system prototype. The experimental validation has demonstrated the feasibility of this new energy storage system operation for use in future grid applications.

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This paper describes the application of a model, initially developed for determining the e-business requirements of a manufacturing organization, to assess the impact of management concerns on the functions generated. The model has been tested on 13 case studies in small, medium and large organizations. This research shows that the incorporation of concerns for generating the requirements for e-business functions improves the results, because they expose issues that are of relevance to the decision making process relating to e-business. Running the model with both and without concerns, and then presenting the reasons for major variances, can expose the issues and enable them to be studied in detail at the individual function/ reason level. © IFIP International Federation for Information Processing 2013.

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This research aims to contribute to understanding the implementation of knowledge management systems (KMS) in the field of health through a case study, leading to theory building and theory extension. We use the concept of the business process approach to knowledge management as a theoretical lens to analyse and explore how a large teaching hospital developed, executed and practically implemented a KMS. A qualitative study was conducted over a 2.5 year period with data collected from semi-structured interviews with eight members of the strategic management team, 12 clinical users and 20 patients in addition to non-participant observation of meetings and documents. The theoretical propositions strategy was used as the overarching approach for data analysis. Our case study provides evidence that true patient centred approaches to supporting care delivery with a KMS benefit from process thinking at both the planning and implementation stages, and an emphasis on the knowledge demands resulting from: the activities along the care pathways; where cross-overs in care occur; and knowledge sharing for the integration of care. The findings also suggest that despite the theoretical awareness of KMS implementation methodologies, the actual execution of such systems requires practice and learning. Flexible, fluid approaches through rehearsal are important and communications strategies should focus heavily on transparency incorporating both structured and unstructured communication methods.

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In this chapter, we discuss performance management systems (PMSs) and high performance work systems (HPWSs) in emerging economies. We start by discussing PMSs, with specific emphasis on PMSs in global organizations. We follow this up with an introduction of HPWSs, and then discuss PMSs and HPWSs in emerging economies. While the list of emerging economies keeps changing, and is rather long, as one might expect, in this chapter we have concentrated on five key emerging economies – China, India, Mexico, South Korea, and Turkey. Performance management is the process through which organizations set goals, determine standards, assign and evaluate work, coach and give feedback, and distribute rewards (Fletcher, 2001). In this connection, organizations all over the world face the challenge of how best to manage performance, including finding ways to motivate employees to sustain high levels of performance. In other words, organizations must develop and implement PMSs that are appropriate for their environment in such a way that high levels of performance can be achieved and sustained over time (DeNisi, Varma and Budhwar, 2008). While all organizations need to address these issues, the way a firm decides to go about addressing these issues is dependent on its location and context. In other words, differences in local norms, culture, law, and technology, make it critical that organizations develop and/or adapt techniques, policies and practices that are appropriate to the setting (see for example, Hofstede, 1993).

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The shifting of global economic power from mature, established markets to emerging markets (EMs) is a fundamental feature of the new realities in the global political economy. Due to a combination of reasons (such as scarcity of reliable information on management systems of EMs, the growing contribution of human resource management (HRM) towards organisational performance, amongst others), the understanding about the dynamics of management of HRM in the EMs context and the need for proactive efforts by key stakeholders (e.g., multinational and local firms, policy makers and institutions such as trade unions) to develop appropriate HRM practice and policy for EMs has now become more critical than ever. It is more so given the phenomenal significance of the EMs predicted for the future of the global economy. For example, Antoine van Agtmael predicts that: in about 25 years the combined gross national product (GNP) of emergent markets will overtake that of currently mature economies causing a major shift in the centre of gravity of the global economy away from the developed to emerging economies. (van Agtmael 2007: 10–11) Despite the present (late 2013 and early 2014) slowdown in the contribution of EMs towards the global industrial growth (e.g., Das, 2013; Reuters, 2014), EMs are predicted to produce 70 per cent of world GDP growth and a further ten years later, their equity market capitalisation is expected to reach US$ 80 trillion, 1.2 times more than the developed world (see Goldman Sachs, 2010).

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With the recent explosion in the complexity and amount of digital multimedia data, there has been a huge impact on the operations of various organizations in distinct areas, such as government services, education, medical care, business, entertainment, etc. To satisfy the growing demand of multimedia data management systems, an integrated framework called DIMUSE is proposed and deployed for distributed multimedia applications to offer a full scope of multimedia related tools and provide appealing experiences for the users. This research mainly focuses on video database modeling and retrieval by addressing a set of core challenges. First, a comprehensive multimedia database modeling mechanism called Hierarchical Markov Model Mediator (HMMM) is proposed to model high dimensional media data including video objects, low-level visual/audio features, as well as historical access patterns and frequencies. The associated retrieval and ranking algorithms are designed to support not only the general queries, but also the complicated temporal event pattern queries. Second, system training and learning methodologies are incorporated such that user interests are mined efficiently to improve the retrieval performance. Third, video clustering techniques are proposed to continuously increase the searching speed and accuracy by architecting a more efficient multimedia database structure. A distributed video management and retrieval system is designed and implemented to demonstrate the overall performance. The proposed approach is further customized for a mobile-based video retrieval system to solve the perception subjectivity issue by considering individual user's profile. Moreover, to deal with security and privacy issues and concerns in distributed multimedia applications, DIMUSE also incorporates a practical framework called SMARXO, which supports multilevel multimedia security control. SMARXO efficiently combines role-based access control (RBAC), XML and object-relational database management system (ORDBMS) to achieve the target of proficient security control. A distributed multimedia management system named DMMManager (Distributed MultiMedia Manager) is developed with the proposed framework DEMUR; to support multimedia capturing, analysis, retrieval, authoring and presentation in one single framework.

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Many restaurant organizations have committed a substantial amount of effort to studying the relationship between a firm’s performance and its effort to develop an effective human resources management reward-and-retention system. These studies have produced various metrics for determining the efficacy of restaurant management and human resources management systems. This paper explores the best metrics to use when calculating the overall unit performance of casual restaurant managers. These metrics were identified through an exploratory qualitative case study method that included interviews with executives and a Delphi study. Experts proposed several diverse metrics for measuring management value and performance. These factors seem to represent all stakeholders’interest.

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The maturation of the cruise industry has led to increased competition which demands more efficient operations. Systems engineering, a discipline that studies complex organizations of material, people, and information, is traditionally only applied in the manufacturing sector; however, it can make significant contributions to service industries such as the cruise industry. The author describes this type of engineering, explores how it can be applied to the cruise industry, and presents two case studies demonstrating applications to the cruise industry luggage delivery process and the information technology help desk process. The results show that this approach can make the processes more productive and enhance profitability for the cruise lines.

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The author describes yield management and the technology used to implement yield management in hotels, issues in usefulness, and legal issues concerning the use of yield management. A look into the future is provided, along with a critique of what further research may be needed in order to raise the level of usefulness of yield management systems in the hotel industry to that found in the airlines.

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Efficient and reliable techniques for power delivery and utilization are needed to account for the increased penetration of renewable energy sources in electric power systems. Such methods are also required for current and future demands of plug-in electric vehicles and high-power electronic loads. Distributed control and optimal power network architectures will lead to viable solutions to the energy management issue with high level of reliability and security. This dissertation is aimed at developing and verifying new techniques for distributed control by deploying DC microgrids, involving distributed renewable generation and energy storage, through the operating AC power system. To achieve the findings of this dissertation, an energy system architecture was developed involving AC and DC networks, both with distributed generations and demands. The various components of the DC microgrid were designed and built including DC-DC converters, voltage source inverters (VSI) and AC-DC rectifiers featuring novel designs developed by the candidate. New control techniques were developed and implemented to maximize the operating range of the power conditioning units used for integrating renewable energy into the DC bus. The control and operation of the DC microgrids in the hybrid AC/DC system involve intelligent energy management. Real-time energy management algorithms were developed and experimentally verified. These algorithms are based on intelligent decision-making elements along with an optimization process. This was aimed at enhancing the overall performance of the power system and mitigating the effect of heavy non-linear loads with variable intensity and duration. The developed algorithms were also used for managing the charging/discharging process of plug-in electric vehicle emulators. The protection of the proposed hybrid AC/DC power system was studied. Fault analysis and protection scheme and coordination, in addition to ideas on how to retrofit currently available protection concepts and devices for AC systems in a DC network, were presented. A study was also conducted on the effect of changing the distribution architecture and distributing the storage assets on the various zones of the network on the system's dynamic security and stability. A practical shipboard power system was studied as an example of a hybrid AC/DC power system involving pulsed loads. Generally, the proposed hybrid AC/DC power system, besides most of the ideas, controls and algorithms presented in this dissertation, were experimentally verified at the Smart Grid Testbed, Energy Systems Research Laboratory. All the developments in this dissertation were experimentally verified at the Smart Grid Testbed.

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Two key solutions to reduce the greenhouse gas emissions and increase the overall energy efficiency are to maximize the utilization of renewable energy resources (RERs) to generate energy for load consumption and to shift to low or zero emission plug-in electric vehicles (PEVs) for transportation. The present U.S. aging and overburdened power grid infrastructure is under a tremendous pressure to handle the issues involved in penetration of RERS and PEVs. The future power grid should be designed with for the effective utilization of distributed RERs and distributed generations to intelligently respond to varying customer demand including PEVs with high level of security, stability and reliability. This dissertation develops and verifies such a hybrid AC-DC power system. The system will operate in a distributed manner incorporating multiple components in both AC and DC styles and work in both grid-connected and islanding modes. The verification was performed on a laboratory-based hybrid AC-DC power system testbed as hardware/software platform. In this system, RERs emulators together with their maximum power point tracking technology and power electronics converters were designed to test different energy harvesting algorithms. The Energy storage devices including lithium-ion batteries and ultra-capacitors were used to optimize the performance of the hybrid power system. A lithium-ion battery smart energy management system with thermal and state of charge self-balancing was proposed to protect the energy storage system. A grid connected DC PEVs parking garage emulator, with five lithium-ion batteries was also designed with the smart charging functions that can emulate the future vehicle-to-grid (V2G), vehicle-to-vehicle (V2V) and vehicle-to-house (V2H) services. This includes grid voltage and frequency regulations, spinning reserves, micro grid islanding detection and energy resource support. The results show successful integration of the developed techniques for control and energy management of future hybrid AC-DC power systems with high penetration of RERs and PEVs.

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This paper uses empirical evidence to examine the operational dynamics and paradoxical nature of risk management systems in the banking sector. It demonstrates how a core paradox of market versus regulatory demands and an accompanying variety of performance, learning and belonging paradoxes underlie evident tensions in the interaction between front and back office staff in banks. Organisational responses to such paradoxes are found to range from passive to proactive, reflecting differing organisational, departmental and individual risk culture(s), and performance management systems. Nonetheless, a common feature of regulatory initiatives designed to secure a more structurally independent risk management function is that they have failed to rectify a critical imbalance of power - with the back office control functions continuing to be dominated by front office trading and investment functions. Ultimately, viewing the 'core' of risk management systems as a series of connected paradoxes rather than a set of assured, robust practices, requires a fundamental switch in emphasis away from a normative, standards-based approach to risk management to one which gives greater recognition to its behavioural dimensions.

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Energy storage technologies are crucial for efficient utilization of electricity. Supercapacitors and rechargeable batteries are of currently available energy storage systems. Transition metal oxides, hydroxides, and phosphates are the most intensely investigated electrode materials for supercapacitors and rechargeable batteries due to their high theoretical charge storage capacities resulted from reversible electrochemical reactions. Their insulating nature, however, causes sluggish electron transport kinetics within these electrode materials, hindering them from reaching the theoretical maximum. The conductivity of these transition metal based-electrode materials can be improved through three main approaches; nanostructuring, chemical substitution, and introducing carbon matrices. These approaches often lead to unique electrochemical properties when combined and balanced.

Ethanol-mediated solvothermal synthesis we developed is found to be highly effective for controlling size and morphology of transition metal-based electrode materials for both pseudocapacitors and batteries. The morphology and the degree of crystallinity of nickel hydroxide are systematically changed by adding various amounts glucose to the solvothermal synthesis. Nickel hydroxide produced in this manner exhibited increased pseudocapacitance, which is partially attributed to the increased surface area. Interestingly, this morphology effect on cobalt doped-nickel hydroxide is found to be more effective at low cobalt contents than at high cobalt contents in terms of improving the electrochemical performance.

Moreover, a thin layer of densely packed nickel oxide flakes on carbon paper substrate was successfully prepared via the glucose-assisted solvothermal synthesis, resulting in the improved electrode conductivity. When reduced graphene oxide was used for conductive coating on as-prepared nickel oxide electrode, the electrode conductivity was only slightly improved. This finding reveals that the influence of reduced graphene oxide coating, increasing the electrode conductivity, is not that obvious when the electrode is already highly conductive to begin with.

We were able to successfully control the interlayer spacing and reduce the particle size of layered titanium hydrogeno phosphate material using our ethanol-mediated solvothermal reaction. In layered structure, interlayer spacing is the key parameter for fast ion diffusion kinetics. The nanosized layered structure prepared via our method, however, exhibited high sodium-ion storage capacity regardless of the interlayer spacing, implying that interlayer space may not be the primary factor for sodium-ion diffusion in nanostructured materials, where many interstitials are available for sodium-ion diffusion.

Our ethanol-mediated solvothermal reaction was also effective for synthesis of NaTi2(PO4)3 nanoparticles with uniform size and morphology, well connected by a carbon nanotube network. This composite electrode exhibited high capacity, which is comparable to that in aqueous electrolyte, probably due to the uniform morphology and size where the preferable surface for sodium-ion diffusion is always available in all individual particles.

Fundamental understandings of the relationship between electrode microstructures and electrochemical properties discussed in this dissertation will be important to design high performance energy storage system applications.