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Condizione: very good. Gut/Very good: Buch bzw. Schutzumschlag mit wenigen Gebrauchsspuren an Einband, Schutzumschlag oder Seiten. / Describes a book or dust jacket that does show some signs of wear on either the binding, dust jacket or pages.

Paperback. Condizione: new. Paperback. During the last 25 years, most of the communication systems have been converted to purely digital technology, although the transmitted content mostly is analog by nature. The principal advantages of digital communication are compression by source encoding, bit error protection by channel coding and robust transmission over noisy channels by appropriate modulation. Digital systems are usually designed for worst case channel conditions. However, often the channel quality is much better, which is not reflected in an improved end-to-end transmission quality due to inevitable quantization noise produced by the source encoder.In this thesis, the focus is set on systems which: are not purely digital anymore benefit from increasing channel qualities and avoid the saturation effect using discrete-time, continuous-amplitude techniques.In the first part, purely analog, i.e., discrete-time and continuous-amplitude transmission systems are considered with linear or nonlinear components. Theoretical performance limits are discussed and a new rate-distortion upper bound is derived which can be evaluated semi-analytically. The performance of linear transmission systems is derived analytically while simulations assess several nonlinear systems including the famous Archimedes spiral. A new class of nonlinear discrete-time analog coding systems, i.e., the Analog Modulo Block Codes (AMBCs) is developed. One important observation is that nonlinear discrete-time, continuous-amplitude systems can be decomposed into a discrete and a continuous-amplitudes part. The considered systems exhibit a considerable gap to capacity but they all circumvent the saturation effect due to the continuous-amplitude components.In the main part of the thesis, these findings are turned into a design principle. Hybrid Digital-Analog (HDA) transmission systems consist of separate digital and analog branches while each is constructed independently. By combining both worlds digital and continuous-amplitude transmission new concepts emerge which fuse their advantages: capacity achieving performance in the digital branch with a huge variety of conventional digital codes plus avoiding the saturation effect in the analog branch. The performance of HDA systems is assessed theoretically as well as by simulations. These Hybrid Digital-Analog (HDA) transmission systems outperform both purely digital and continuous-amplitude concepts. HDA transmission is an attractive solution for wireless systems such as microphones, loudspeakers or distributed sensors. Shipping may be from multiple locations in the US or from the UK, depending on stock availability.…

Paperback. Condizione: New. During the last 25 years, most of the communication systems have been converted to purely digital technology, although the transmitted content mostly is analog by nature. The principal advantages of digital communication are compression by source encoding, bit error protection by channel coding and robust transmission over noisy channels by appropriate modulation. Digital systems are usually designed for worst case channel conditions. However, often the channel quality is much better, which is not reflected in an improved end-to-end transmission quality due to inevitable quantization noise produced by the source encoder.In this thesis, the focus is set on systems which. are not purely digital anymore. benefit from increasing channel qualities and. avoid the saturation effect using discrete-time, continuous-amplitude techniques.In the first part, purely analog, i.e., discrete-time and continuous-amplitude transmission systems are considered - with linear or nonlinear components. Theoretical performance limits are discussed and a new rate-distortion upper bound is derived which can be evaluated semi-analytically. The performance of linear transmission systems is derived analytically while simulations assess several nonlinear systems including the famous Archimedes spiral. A new class of nonlinear discrete-time analog coding systems, i.e., the Analog Modulo Block Codes (AMBCs) is developed. One important observation is that nonlinear discrete-time, continuous-amplitude systems can be decomposed into a discrete and a continuous-amplitudes part. The considered systems exhibit a considerable gap to capacity but they all circumvent the saturation effect due to the continuous-amplitude components.In the main part of the thesis, these findings are turned into a design principle. Hybrid Digital-Analog (HDA) transmission systems consist of separate digital and analog branches while each is constructed independently. By combining both worlds - digital and continuous-amplitude transmission - new concepts emerge which fuse their advantages: capacity achieving performance in the digital branch with a huge variety of conventional digital codes plus avoiding the saturation effect in the analog branch. The performance of HDA systems is assessed theoretically as well as by simulations. These Hybrid Digital-Analog (HDA) transmission systems outperform both purely digital and continuous-amplitude concepts. HDA transmission is an attractive solution for wireless systems such as microphones, loudspeakers or distributed sensors.…

Paperback. Condizione: New. One of the most important tools in the metal forming technology is the integrated process and microstructual simulation using Finite Element Methods (FEM). It has become more and more popular in recent years, especially in the segment of hot metal forming, e.g. open die forging of large scaled and hardly deformable materials, such as nickel-based super alloys for turbine shaft. Theoretically using this method it is possible to calculate the microstructual evolution along the whole process chain in the numerical simulation of the considered metal forming process. Based on this knowledge a series of benefits can be achieved for the practice, such as to optimize a present metal forming process, to predict the mechanical properties of the final products under the given forming conditions, to detect the possible product failures prematurely, to assist the design of a new production chain and so on. In the face of these trends of the scientific research as well as the industrial demands, different material models have been released in the market to combine the commercial FEM programs specialized in the numerical simulation of metal forming. Among others microstructure-based ow stress models show outstanding performance. Through this kind of material model not only the microstructure such as recrystallization and grain size, but also the interaction between the microstructual evolution and the working hardening, effectively ow stress, can be quantitatively represented.Towards accurate and efficient material modeling, the model parameters have to be determined conveniently and reliably. For this propose a new Hybrid strategy combining the advantages both of direct and indirect methods has been proposed using the example of StrucSim, which is a very good representative of a mircostructure-based ow stress model. At first different aspects, which lead to the disadvantages of the conventional method, i.e. direct method, were discussed. In doing so a high manganese steel was characterized as an example by stepwise graphical and regression analysis. It was found that, the precondition of direct methods, namely recording ow curves under constant Zener-hollomon-parameter conditions, are basically not possible due to both limitations of test equipment and unconquerable physical mechanism like dissipation heating. The common solution to compensate these factors may lead to further inaccuracies, uncertainties and complexities despite large testing and evaluating efforts. Further in order to improve the model quality calibrated by the conventional direct method an efficient hybrid strategy has been derived by combining inverse analysis with offline calculation of ow stress and microstructure. Three different variations of the hybrid strategy were introduced to deal with different available experimental databases, such as isothermal and non-isothermal ow curves. To demonstrate the developed routines of these three hybrid possibilities two kinds of materials including.…

Paperback. Condizione: New. Long Term Evolution (LTE) standardized by 3GPP operates fully packet switched and does not have a circuit switched domain as older systems HSPA, UMTS and GSM. It must support a minimum number of voice calls to be recognized as IMT-Advanced system by ITU. Therefore ITU has published the IMT-Advanced Evaluation Guidelines describing evaluation scenarios and minimum quality of service demands for voice calls to be evaluated by system level simulation. Those guidelines require transmission of VoIP packets within 50 ms over the air interface and packet loss rate below 2 %.3GPP came to the conclusion Voice-over-LTE (VoLTE) with semi-persistent scheduling satisfies the ITU demands. This was verified by independent evaluation groups. Semi-persistent scheduling reserves radio resources for VoIP packets for the duration of a talk spurt while other packets, e.g. retransmissions of lost packets, individually receive resources (dynamic scheduling). Advantage is significantly decreased signaling overhead but the method is more complex than the classical approach individually assigning radio resources for each packet. Individual assignment of radio resources is also used for data traffic of so called Over-the-Top (OTT) VoIP applications.This thesis compares VoIP capacity of VoLTE and OTT focusing on the impact of the radio link. Radio resource assignment optimized for delay critical traffic like VoIP is assumed for OTT to allow a fair comparison. A concept developed by me to design complex VoIP schedulers from basic resource assignment algorithms is described. It is applied for VoLTE and OTT. The openWNS/IMTAPhy simulator developed at RWTH Aachen University ComNets Research Group and extended at TU Munich Chair of Communication Networks is enhanced for VoIP evaluation based on that concept. Methods to improve VoIP capacity are evaluated separately for up- and downlink. Different channel prediction strategies are applied for each direction and based on that transmission rate adaptation is performed.Results show improved capacity through aggressive rate adaptation and resource assignment resulting in higher data rates and therefore reduced resource demand while at the same time increasing packet error rate. Too aggressive parameters significantly reduce VoIP capacity while moderate adjustments increase it by ca. 15 % in the downlink and 10 % in the uplink for VoLTE. OTT cannot benefit from these improvements if the number of control channels is limited and becomes a bottleneck. If more control channels were available than defined by the current standard OTT VoIP capacity could be improved for downlink. High uplink interference variance makes channel prediction more difficult and prevents capacity gains for OTT as achieved with VoLTE.Besides simulation results an analytical discrete time Engset queueing model was described and solved for its waiting time distribution to determine VoIP capacity in scenarios without and with adjacent channel interference from neighb.…

Paperback. Condizione: New. In 2007 the International Telecommunication Union, Radiocommunication Sector (ITU-R) published evaluation guidelines for future mobile broadband radio networks including a minimal VoIP capacity that the IEEE 802.16m WiMAX system had to meet, proven by system level simulation. These evaluation guidelines are the foundation of this work that shows that relayenhanced 4G networks do not only meet the requirements but exceed them by far. The key-requirement for packet based VoIP services that has been set in the evaluation guidelines demands that the end-to-end packet delay of at least 98% of user data traffic stays below 50 ms.Since 2011 proposals of ComNets to implement relays into mobile radio networks to increase system capacity are part of all 4G systems (LTE and WiMAX). This work investigates the voice over IP (VoIP) capacity of the relay-enhanced WiMAX system by system simulation. The work presents a modular approach that has been developed by my colleagues and myself to implement the WiMAX protocol stack, also known as WiMAC, into the openWNS simulator. The approach is based on atomic protocol functions that are bound to so called FU and interconnected in a network of functional units (FUs) and thereby implement the WiMAX protocol bit-by-bit. Besides the performance evaluation of VoIP services based on the ITU-R scenarios and channel model, this work also determines the optimal radio resource configuration for up- and downlink and furthermore investigates the impact of RS location on system capacity. Core functions of the simulator are being validated by comparison of equivalent results of other simulators.Cumulative distribution functions of the end-to-end delay of VoIP user data packets, determined by simulation show that relays double the carried VoIP traffic load compared to a scenario without relay stations (RSs) due to the improved prediction of the uplink channel state that is the bottleneck of the system.The performance enhancement is a surprise since relays increase the end-to-end packet delay and packet error due to an additional transmission compared to conventional single-hop operation.…

Paperback. Condizione: New. Ever since humans have existed, they have impacted the earth in many different ways (Redman, 1999). Currently, important impacts are associated with the excessive use of non-renewable fossil fuels such as coal, oil and natural gas. Most fossil fuels are used for electricity generation, heating and mobility (eia, 2011), and as feedstock in the chemical industry (IEA et al., 2013). Moreover, the use of fossil fuels is associated with carbon dioxide emissions (CO2) (IEA, 2014; Leimk¨uhler, 2010). Emitting CO2 into the atmosphere leads to global warming and disrupts the natural carbon cycle (Stocker et al., 2013). To close the disrupted carbon cycle, CO2 can be captured and re-utilized, thereby mitigating global warming and saving fossil resources (Styring et al., 2014).CO2 can be captured from current anthropogenic CO2 sources or directly from the atmosphere. Captured CO2 can then be utilized as valuable physical product "as such"or as alternative carbon feedstock for fuels, chemicals and materials. The general concept of CO2 Capture and Utilization (CCU) can be considered established: already today, CO2 is captured and utilized in processes in the chemical industry (Aresta et al., 2014). However, the scope of CO2 utilization is limited. Despite the existing industrial implementations as well as continuous progress and current efforts in CCU research, most CCU technologies are still in early stages of development. Besides the limited technological readiness, CCU is intrinsically challenging since both capture and utilization of CCU typically require substantial amounts of energy (Sakakura et al., 2007). If the provision of energy relies on fossil resources, indirect CO2 emissions are caused. Therefore, the intuitively expected environmental benefits from using CO2 are not given by default (Peters et al., 2011b). In fact, it cannot be ruled out that a tediously accomplished CCU process is finally environmentally less sustainable than a conventional fossil-based route. Therefore, it is desirable to know whether a specific CCU process is environmentally favorable. For this purpose, a reliable environmental assessment of CCU is required.As indicators for the environmental performance of CCU, a large variety of approaches are proposed ranging from qualitative design principles (Anastas andWarner, 1998) and metrics for 'green' chemistry (Constable et al., 2002) to CCU-specific ad-hoc criteria (Peters et al., 2011b; M¨uller and Arlt, 2014). These approaches are rather intended to guide the development towards 'sustainable' CCU processes than to systematically quantify the actual environmental impacts. In contrast to these approaches, Life-Cycle Assessment (LCA) is a systematic and standardized methodology to analyze the actual environmental impacts of products and processes (ISO 14040, 2009). Although LCA is frequently advocated for the environmental assessment of CCU (Aresta and Dibenedetto, 2007b; Peters et al., 2011b; Quadrelli et al., 2011), it is not.…

PAP. Condizione: New. New Book. Shipped from UK. Established seller since 2000.

Paperback. Condizione: New. The key measure to mitigate climate change is the reduction of greenhouse gas emissions. Hereby, energy-intensive industry plays a key role due to its substantial greenhouse gas emissions. A substantial share of these greenhouse gas emissions is caused by energy supply. Thus, energy supply needs to be more efficient in industry.In large industrial sites, on-site energy systems often supply production systems. Both systems thereby optimize their operation with respect to an objective such as operational cost or revenue. This thesis provides optimization methods for these large industrial sites. The optimization methods reflect two relationships between both systems: Both systems can either follow the same objective or system-specific objectives. The same objective exists, e.g., if both systems belong to one company. System-specific objectives exist, e.g., if both systems belong to different companies.For the case that both systems follow the same objective, a method is presented for the integrated synthesis of both systems. For the same case, a method is presented for integrated scheduling to provide control reserve. For the case that energy and production systems have system-specific objectives, two cases are distinguished: incomplete and complete information exchange. For incomplete information exchange, an optimization method is introduced for the coordination between a single energy and a single production system. This optimization method is then extended to multiple energy and multiple production systems. For complete information exchange between the systems, a bilevel problem is formulated. For solving the bilevel problem, an existing solution algorithm is adapted.All methods presented in this thesis are applied to case studies, and advantages and disadvantages are examined. The case studies show that no method provides the optimal solution for the production system in all identified relationships between the systems. Thus, depending on the case at hand, the respective optimization method has to be applied. Overall, this thesis presents optimization methods for all identified relationships between energy and production systems. Thus, this thesis enables the selection of a suitable optimization method for all kind of production systems with decentralized energy supply. …

PAP. Condizione: New. New Book. Shipped from UK. Established seller since 2000.

Condizione: New.

Paperback. Condizione: New. Terrestrial broadcast is traditionally realized over High Tower High Power (HTHP) networks which have been preserved in the transition from the analog PAL to the first generation of the digital DVB-T technology. The drawback of this traditional network design is its spectral inefficiency. The demand for providing more TV programs with HD quality as well as the increasing spectrum consumption of mobile internet services, with video streaming being one of the driving factors, necessitate a re-optimization of the current broadcast network and a more efficient allocation of frequencies.In this thesis, three options for a future frequency-efficient evolution and coexistence of terrestrial TV and mobile internet are specified and investigated:- Transition from the current terrestrial broadcast with DVB-T to its successor DVB-T2 while retaining the HTHP network infrastructure- Switch-over from DVB-T to DVB-T2 with transition to a Low Tower Low Power (LTLP) network infrastructure- Utilization of the evolved Multimedia Broadcast/Multicast Service (eMBMS) within an existing LTLP LTE network.All three system concepts are evaluated in terms of bit error rate performance and system throughput. Additionally, coverage and total network transmit power are determined by system level simulations for different propagation models and network topologies. Although the emphasis of this thesis is on the evaluation of the performance and feasibility of the three scenarios from a technical point of view, political, regulatory, and economic considerations are addressed in short.In summary, all three options bear a huge potential for a significant reduction of the spectrum required for terrestrial broadcast. The introduction of DVB-T2 for terrestrial broadcast is a good compromise between performance, cost, and regulation. However, its full spectral potential can only be exploited in combination with LTLP network concepts. Furthermore, this thesis proves the importance of alternative terrestrial broadcasting concepts, which are highly beneficial for a further convergence of TV and mobile internet. The enhanced multimedia service eMBMS (LTE and 5G) represents an attractive solution for replacing or supplementing future terrestrial broadcast systems, especially for the distribution of personal and regional TV content.…

Paperback. Condizione: new. Paperback. Terrestrial broadcast is traditionally realized over High Tower High Power (HTHP) networks which have been preserved in the transition from the analog PAL to the first generation of the digital DVB-T technology. The drawback of this traditional network design is its spectral inefficiency. The demand for providing more TV programs with HD quality as well as the increasing spectrum consumption of mobile internet services, with video streaming being one of the driving factors, necessitate a re-optimization of the current broadcast network and a more efficient allocation of frequencies.In this thesis, three options for a future frequency-efficient evolution and coexistence of terrestrial TV and mobile internet are specified and investigated: Transition from the current terrestrial broadcast with DVB-T to its successor DVB-T2 while retaining the HTHP network infrastructure Switch-over from DVB-T to DVB-T2 with transition to a Low Tower Low Power (LTLP) network infrastructure Utilization of the evolved Multimedia Broadcast/Multicast Service (eMBMS) within an existing LTLP LTE network.All three system concepts are evaluated in terms of bit error rate performance and system throughput. Additionally, coverage and total network transmit power are determined by system level simulations for different propagation models and network topologies. Although the emphasis of this thesis is on the evaluation of the performance and feasibility of the three scenarios from a technical point of view, political, regulatory, and economic considerations are addressed in short.In summary, all three options bear a huge potential for a significant reduction of the spectrum required for terrestrial broadcast. The introduction of DVB-T2 for terrestrial broadcast is a good compromise between performance, cost, and regulation. However, its full spectral potential can only be exploited in combination with LTLP network concepts. Furthermore, this thesis proves the importance of alternative terrestrial broadcasting concepts, which are highly beneficial for a further convergence of TV and mobile internet. The enhanced multimedia service eMBMS (LTE and 5G) represents an attractive solution for replacing or supplementing future terrestrial broadcast systems, especially for the distribution of personal and regional TV content. Shipping may be from multiple locations in the US or from the UK, depending on stock availability.…

PAP. Condizione: New. New Book. Shipped from UK. Established seller since 2000.

Paperback. Condizione: New. Transmitting analog audio, video, or sensor data with a digital system requires sampling and quantization. While a sampled bandlimited signal can be reconstructed perfectly if the Nyquist-Shannon sampling theorem is met, quantization unavoidably adds irreversible errors. Given a certain bitrate for quantization (or source coding in general), the achievable signal quality is therefore limited. Transmission of the signal over a noisy channel causes additional errors. If some part of the bitrate is used for protecting the signal with a channel code, these additional errors can be reduced or even eliminated. However, this reduces the achievable maximum quality if the gross bitrate is fixed. Since this compromise between quantization and channel coding is often designed for the worst-case channel, the signal quality saturates early with increasing channel quality, and transmission over a better channel is far below optimum.Instead of conventional digital systems, this thesis covers a continuous-amplitude, discrete-time system. Such a system does not exhibit this saturation of the signal quality, as its performance further improves with increasing channel quality. An example of such a system is a channel coding strategy using analog modulo block codes (AMB codes) for error protection. The encoder multiplies the unquantized symbol vector with a code matrix and limits the transmission power with a modulo operation. In practice, AMB coding is implemented by digital signal processing. The digital representation of the information symbols can be very precise and no coarse quantization is required for bitrate reduction.In this thesis, AMB codes are analyzed, designed, and evaluated. The resulting code words, consisting of a lattice and a continuous component, are presented and analyzed. New decoding techniques are developed and evaluated. Additionally, a novel method to analytically estimate the quality of the decoded signal in terms of signal-to-distortion ratio (SDR) can replace computationally much more demanding simulations in many cases. This estimation strategy allows evaluating the usefulness of codes with different dimensionalities. A new, efficient design concept is developed for codes with a single input symbol, which are most promising in terms of complexity and performance. Asystem using AMBcodes outperforms traditional digital transmission systems with short block lengths for medium to high signal-to-noise ratios on the channel. Due to their typically very short block length and low encoding complexity, AMB codes are especially well suited for low-delay, low-power applications, such as hearing aids, wireless microphones, and wireless sensor networks. …

Condizione: New.

Paperback. Condizione: New. The emerging interest on the application of vacuum interrupter (VI) in medium and even high-voltage application has led to increase of comprehensive and fundamental research on VIs. Application of these interrupters is however hindered by limitation of interrupting capability, when high-current anode phenomena occur.The goal of the work is to investigate the high-current anode phenomena using spectroscopic methods se well as electrical measurements. Different current waveforms, i.e. AC and DC pulses are applied. Moreover, the impact of vacuum interrupter properties, e.g. electrode diameter and geometries, contact materials, opening time and opening speed on the formation of high-current anode phenomena are investigated.The results reveal that the threshold current of the high-current anode formation is dominated by the current in case of high-frequency pulsed, whereas in case of pulsed DC, it is controlled by transferred charge.Along with typical and already known high-current modes, i.e. footpoint, anode spot, and intense modes, a new type of high current anode mode, anode spot type 2, is introduced. Anode spot type 2 is similar to the intense mode but it appears at larger gap length. In contrast to anode spot (anode spot type 1), both anode and cathode are active in case of anode spot type 2. The line emission intensities of all species increase near the anode and the cathode in case of anode spot type 2. The anode spot type 2 is examined by determining radiating density, ground state density and electron density which is about two times higher compared to anode spot type 1.Optical emission spectroscopy combined with high-speed camera imaging (video spectroscopy) is used to investigate the temporal and spatial distribution of Cu I, Cu II, and Cu III during discharge modes.The results show different patterns during discharge modes. The formation of anode plume, is investigated using video spectroscopy. Existence diagrams confirm that the anode plume appears always after the extinction of anode spot type 2 in case of CuCr electrodes before current zero. The results unfold that the emission from the inner part of anode plume is covered by atomic lines, whereas the outer part is dominated by ionic line radiation. Anode plume formation which is a result of shock effect in front of the anode shows that anode plume contracts first and then it expands. Radiating densities of atomic and ionic Cu lines, and temporal evaluation of temperatures inside the anode plume are determined during the formation of anode plume.The ground state density of Cr I before and after current zero is calculated for two cases; with and without anode plume using broadband absorption spectroscopy. The results point out that the ground state density after current zero is higher in case of anode plume. Moreover, during active phase the ground state density is higher in case of anode spot type 2 compared to anode spot type 1. Furthermore, the temporal evolution of ground state den.…

Condizione: As New. Unread book in perfect condition.

PAP. Condizione: New. New Book. Shipped from UK. Established seller since 2000.

PAP. Condizione: New. New Book. Shipped from UK. Established seller since 2000.

PAP. Condizione: New. New Book. Shipped from UK. Established seller since 2000.

PAP. Condizione: New. New Book. Shipped from UK. Established seller since 2000.

PAP. Condizione: New. New Book. Shipped from UK. Established seller since 2000.

Condizione: As New. Unread book in perfect condition.

Paperback. Condizione: new. Paperback. Thermal energy storage (TES) helps to reduce energy consumption and peak demands by balancing heat supply and demand on all time scales from short-term to seasonal. Thus, TES is an important technology to improve flexibility and efficiency of energy systems. In particular, adsorption TES systems, which exploit the enthalpy of adsorption, provide high energy storage density and high efficiency.The present thesis therefore analyzes an adsorption TES unit for residential and industrial applications. Industrial energy supply can be made more efficient by integrating waste heat into the process heat supply and by using energy-efficient technologies. Adsorption TES contributes to both approaches: waste heat can be integrated via the heat pump effect and TES allows for energy-efficient cogeneration heat supply for batch processes.We evaluate the energy efficiency of the heat supply for an industrial batch process by adsorption TES and cogeneration. To evaluate the performance, a dynamic model of an adsorption TES unit is developed. Measurements from earlier experimental investigations of an adsorption TES unit are used to calibrate the storage model. As benchmark, a peak boiler and TES based on a phase-change material are considered. Our comparison demonstrates the significance of the process conditions for the choice of the appropriate technology. The study shows that adsorption TES offers significant potential to increase the energy efficiency: primary energy consumption can be reduced by up to 25%. The key is the availability of low-grade heat at times of discharging and of a low-grade heat demand when charging the storage unit.The study reveals that a comprehensive evaluation of the storage performance requires dynamic models that precisely describe the storage performance and the heat losses in particular. The present thesis provides the basis with a new experimental setup to precisely characterize the adsorption TES unit. In an experimental analysis of the TES performance, we quantify the heat losses, the energy recovery ratio (6991%) and the energy storage density (20.4 kWh/m3) of the adsorption TES unit for varying charging temperatures and storage times ranging from continuous operation to seasonal storage.The extensive experimental study provides the basis to improve our model of the adsorption TES unit. The model is calibrated to heat-loss measurements and a storagecycle measurement. We quantify the simulation accuracy and validate the model with measurements at various process conditions. The model achieves a higher prediction accuracy than other models from literature. The thesis thus provides a basis for future investigations of energy systems to exploit the advantages of adsorption TES. Shipping may be from multiple locations in the US or from the UK, depending on stock availability.…

PAP. Condizione: New. New Book. Shipped from UK. Established seller since 2000.

PAP. Condizione: New. New Book. Shipped from UK. Established seller since 2000.

Paperback. Condizione: new. Paperback. In this thesis, two novel synthesis methodologies are proposed to facilitate the use of optimization for efficient and reliable DESS synthesis, thus making optimization accessible for practitioners: The automated superstructure-based and the superstructurefree synthesis methodology. The proposed methodologies avoid both the a priori definition of a superstructure and the manual definition of many technology-specific replacement rules while accounting for the major characteristics inherent to DESS synthesis problems. The superstructure-based framework (chapter 4) relies on an algorithm for automated superstructure-generation. The method employs a successive superstructure expansion and optimization strategy that continuously increases the number of units included in the superstructure until the optimal solution is identified. The superstructure-free approach (chapter 5) combines evolutionary optimization and deterministic optimization for simultaneous alternatives generation and optimization. A knowledge-integrated mutation operator is proposed that relies on a hierarchically-structured graph, the so-called energy conversion hierarchy (ECH). The ECH efficiently defines all reasonable replacement rules, thus avoiding their manual definition. The mutation operator performs structural replacements for the evolutionary generation of solution alternatives. Both synthesis methodologies use a generic component-based modeling framework, thus making the methodologies independent of the employed mathematical programming formulation. In this thesis, a robust MILP formulation is used that allows to simultaneously optimize the structure, sizing, and operation of distributed energy supply systems accounting for time-varying load profiles, continuous equipment sizing, economy of scale of equipment investment, and part-load equipment performance. Shipping may be from multiple locations in the US or from the UK, depending on stock availability.…

PAP. Condizione: New. New Book. Shipped from UK. Established seller since 2000.

PAP. Condizione: New. New Book. Shipped from UK. Established seller since 2000.