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Zustand: 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.

Taschenbuch. Zustand: Gut. 262 S. Buch ist in gutem Zustand, geringe Gebrauchs- Alters- oder Lagerungsspuren. ISBN: 3810702005 Due to new EU packaging regulations, we are currently unable to ship to many EU countries. Shipping to Germany, the Netherlands, Ireland, Finland, and the Baltic states is possible. Deliveries to border-based parcel lockers or cross-border parcel forwarding services remain possible. Shipping to all countries outside the EU also remains possible. Sprache: Deutsch Gewicht in Gramm: 200.…

Zustand: good. Befriedigend/Good: Durchschnittlich erhaltenes Buch bzw. Schutzumschlag mit Gebrauchsspuren, aber vollständigen Seiten. / Describes the average WORN book or dust jacket that has all the pages present.

8° Gebundene Ausgabe. Zustand: Neu. 208 Seiten 1. Auflage B03-04-03F Sprache: Deutsch Gewicht in Gramm: 477.

8° Gebundene Ausgabe. Zustand: Sehr gut. 208 Seiten Fast wie neu und ungelesen, 1. Auflage B13-01-06L Sprache: Deutsch Gewicht in Gramm: 477.

gebundene Ausgabe. Zustand: Gut. 160 S. ; Der Erhaltungszustand des hier angebotenen Werks ist trotz seiner Bibliotheksnutzung sehr sauber. Es befindet sich neben dem Rückenschild lediglich ein Bibliotheksstempel im Buch; ordnungsgemäß entwidmet. Originalschutzumschlag vorhanden, kleine Einrisse. Sprache: Deutsch Gewicht in Gramm: 280. …

Zustand: 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.

M. 2 gezeichn. Initialen v. Franz Müller. Gr.-8°. 10 ungezählte Bll. Bütten. OKart m. i.d. Klappen verleimtem OSchutzumschl. (= Fünfter Druck der "Sammlung Eggebrecht"). Beiliegen 6 Zeitungsausschnitte d. Zeit (Ost), teils m. Originalbeiträgen d. Autors. Erstausgabe. Rücken min. berieben, ob. Ecke d. Rückens m. min. Knick; schönes sauberes Expl.…

Broschur/Klebebindung. Zustand: Gut. 230 S. Buch ist in gutem Zustand, geringe Gebrauchs- Alters- oder Lagerungsspuren. ISBN: 3861300109 Due to new EU packaging regulations, we are currently unable to ship to many EU countries. Shipping to Germany, the Netherlands, Ireland, Finland, and the Baltic states is possible. Deliveries to border-based parcel lockers or cross-border parcel forwarding services remain possible. Shipping to all countries outside the EU also remains possible. Sprache: Deutsch Gewicht in Gramm: 400.…

Hardcover. Zustand: Very Good. 1st Edition. Folio, heavy book, German text (some Italian, English), ill, 22 essays on the craft/art of books and bookbinding, typography, illustrations, 315pps, origins of vellum, Ukrainian book graphics (some colour), incunabula, Hungarian books, modern art, type, early Bologna typefaces, modern type design, old Chinese book illustrations, etc. …

Paperback. Zustand: new. Paperback. 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 a nickel-based super alloy and a high manganese steel have been taken into account. The investigation has shown that through the introduced hybrid methods better model quality can be achieved even with less experimental data. Owing to the convenience of the inverse technique much experimental and evaluating effort and complexities can be avoided. Finally, another inverse analysis based on inhomogeneous deformation has been proposed, in which hot compression tests with double cone specimen were employed. Thanks to the inhomogeneity of strain and microstructure distribution within the specimen, it becomes possible to get sufficient relevant information as constraints for the inverse parameterization through even fewer experiments. In addition, the established routine of a hybrid strategy as well as the inverse analysis based on non-uniform deformation enhances the trans Shipping may be from multiple locations in the US or from the UK, depending on stock availability. …

Paperback. Zustand: New.

Paperback. Zustand: new. Paperback. 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 neighbor cells.In the Urban Macrocell scenario lowest downlink VoIP capacity results 43 users / cell / MHz for OTT and 41 users / cell / MHz for VoLTE were obtained with unlimited number of control channels. The Downlink is the bottleneck and therefore determines the overall VoIP capacity. Allowing users with bad channel condition to transmit at higher data rates than suggested by the rate adaptation algorithm reduces resource occupation but at the same time increases packet error rate. VoIP capacity is increased to 48 and 47 users / cell / MHz this way for OTT and VolTE, respectively.From this it is concluded that dynamic scheduling used by OTT is capable to provide sufficient VoIP capacity without the complexity introduced by SPS given that sufficient control channels are available, as expected in reality. Shipping may be from multiple locations in the US or from the UK, depending on stock availability.…

Paperback. Zustand: 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. Zustand: 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. Zustand: 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.…

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

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

Paperback. Zustand: 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. Zustand: New. New Book. Shipped from UK. Established seller since 2000.

Zustand: New.

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

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

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

Zustand: New.

Paperback. Zustand: 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. Zustand: New. New Book. Shipped from UK. Established seller since 2000.

Zustand: As New. Unread book in perfect condition.

Zustand: As New. Unread book in perfect condition.

Zustand: New.