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Internationales Theater und Inter-Kulturen Bloch, Natalie Book published by Wehrhahn - 2nd ed. revised (2017) Detailed reference viewed: 127 (3 UL)Symbol-level Precoding for the Non-linear Multiuser MISO Downlink Channel Spano, Danilo ; ; Chatzinotas, Symeon et al in IEEE Transactions on Signal Processing (2017) This paper investigates the problem of the interference among multiple simultaneous transmissions in the downlink channel of a multi-antenna wireless system. A symbol-level precoding scheme is considered ... [more ▼] This paper investigates the problem of the interference among multiple simultaneous transmissions in the downlink channel of a multi-antenna wireless system. A symbol-level precoding scheme is considered, in order to exploit the multi-user interference and transform it into useful power at the receiver side, through a joint utilization of the data information and the channel state information. In this context, this paper presents novel strategies which exploit the potential of symbol-level precoding to control the per-antenna instantaneous transmit power. In particular, the power peaks amongst the transmitting antennas and the instantaneous power imbalances across the different transmitted streams are minimized. These objectives are particularly relevant with respect to the non-linear amplitude and phase distortions induced by the per-antenna amplifiers, which are important sources of performance degradation in practical systems. More specifically, this work proposes two different symbol-level precoding approaches. A first approach performs a weighted per-antenna power minimization, under Quality-of-Service constraints and under a lower bound constraint on the per-antenna transmit power. A second strategy performs a minimization of the spatial peak-to-average power ratio, evaluated amongst the transmitting antennas. Numerical results are presented in a comparative fashion to show the effectiveness of the proposed techniques, which outperform the state of the art symbol-level precoding schemes in terms of spatial peak-to-average power ratio, spatial dynamic range, and symbol-error-rate over non-linear channels. [less ▲] Detailed reference viewed: 202 (15 UL)Mechanical strength assessment of a drilled hole in the contralateral cortex at the end of the open wedge for high tibial osteotomy. Diffo Kaze, Arnaud ; Maas, Stefan ; et al in Journal of Experimental Orthopaedics (2017), 4(1), BACKGROUND: This study aimed to investigate, by means of finite element analysis, the effect of a drill hole at the end of a horizontal osteotomy to reduce the risk of lateral cortex fracture while ... [more ▼] BACKGROUND: This study aimed to investigate, by means of finite element analysis, the effect of a drill hole at the end of a horizontal osteotomy to reduce the risk of lateral cortex fracture while performing an opening wedge high tibial osteotomy (OWHTO). The question was whether drilling a hole relieves stress and increases the maximum correction angle without fracture of the lateral cortex depending on the ductility of the cortical bone. METHODS: Two different types of osteotomy cuts were considered; one with a drill hole (diameter 5 mm) and the other without the hole. The drill holes were located about 20 mm distally to the tibial plateau and 6 mm medially to the lateral cortex, such that the minimal thickness of the contralateral cortical bone was 5 mm. Based on finite element calculations, two approaches were used to compare the two types of osteotomy cuts considered: (1) Assessing the static strength using local stresses following the idea of the FKM-guideline, subsequently referred to as the "FKM approach" and (2) limiting the total strain during the opening of the osteotomy wedge, subsequently referred to as "strain approach". A critical opening angle leading to crack initiation in the opposite lateral cortex was determined for each approach and was defined as comparative parameter. The relation to bone aging was investigated by considering the material parameters of cortical bones from young and old subjects. RESULTS: The maximum equivalent (von-Mises) stress was smaller for the cases with a drill hole at the end of the osteotomy cut. The critical angle was approximately 1.5 times higher for the specimens with a drill hole compared to those without. This corresponds to an average increase of 50%. The calculated critical angle for all approaches is below 5°. The critical angle depends on the used approach, on patient's age and assumed ductility of the cortical bone. CONCLUSIONS: Drilling a hole at the end of the osteotomy reduces the stresses in the lateral cortex and increases the critical opening angle prior to cracking of the opposite cortex in specimen with small correction angles. But the difference from having a drill hole or not is not so significant, especially for older patients. The ductility of the cortical bone is the decisive parameter for the critical opening angle. [less ▲] Detailed reference viewed: 866 (12 UL)Energy efficient transmission in MIMO interference channels with QoS constraints Yang, Yang ; in Proc. 8th IEEE International Workshop on Computational Advances in Multi-Sensor Adaptive Processing (2017, December) Detailed reference viewed: 153 (4 UL)A global optimization heuristic for the decomposed static anticipatory network traffic control problem anticipatory network traffic control problem Rinaldi, Marco ; ; Viti, Francesco in Transportation Research Procedia (2017) Developing traffic control strategies taking explicitly into account the route choice behavior of users has been widely recognized irregularities in the solution space shape, such as non-convexity and non ... [more ▼] Developing traffic control strategies taking explicitly into account the route choice behavior of users has been widely recognized irregularities in the solution space shape, such as non-convexity and non-smoothness. In this work, we propose an extended as a very challenging problem. Furthermore, the inclusion of user behavior in optimization based control schemes introduces strong decomposition scheme for the anticipatory traffic control problem, based upon our previous contributions, which aims at i) reducing irregularities in the solution space shape, such as non-convexity and non-smoothness. In this work, we propose an extended the computational complexity of the problem by approaching it in a controller-by-controller fashion, and ii) internalizing specific decomposition scheme for the anticipatory traffic control problem, based upon our previous contributions, which aims at i) reducing constraints in the objective function, guiding the optimization process away from non-significant minima, such as flat regions. the computational complexity of the problem by approaching it in a controller-by-controller fashion, and ii) internalizing specific Through two small scale test networks and different, randomly chosen initial points, we compare how the proposed extension constraints in the objective function, guiding the optimization process away from non-significant minima, such as flat regions. influences optimization results with respect to our previously developed decomposed approach, as well as centralized schemes. Through two small scale test networks and different, randomly chosen initial points, we compare how the proposed extension influences optimization results with respect to our previously developed decomposed approach, as well as centralized schemes. [less ▲] Detailed reference viewed: 52 (2 UL)Zentrale Ergebnisse und Herausforderungen – Synopse zum Sozialbericht Esch/Alzette 2017 Heinz, Andreas ; Willems, Helmut E-print/Working paper (2017) Detailed reference viewed: 82 (7 UL)Distributed synchronization of euclidean transformations with guaranteed convergence Thunberg, Johan ; Goncalves, Jorge ; in 56th IEEE Conference on Decision and Control (2017, December) This paper addresses synchronization of Euclidean transformations over graphs. Synchronization in this context, unlike rendezvous or consensus, means that composite transformations over loops in the graph ... [more ▼] This paper addresses synchronization of Euclidean transformations over graphs. Synchronization in this context, unlike rendezvous or consensus, means that composite transformations over loops in the graph are equal to the identity. Given a set of non-synchronized transformations, the problem at hand is to find a set of synchronized transformations approximating well the non-synchronized transformations. This is formulated as a nonlinear least-squares optimization problem. We present a distributed synchronization algorithm that converges to the optimal solution to an approximation of the optimization problem. This approximation stems from a spectral relaxation of the rotational part on the one hand and from a separation between the rotations and the translations on the other. The method can be used to distributively improve the measurements obtained in sensor networks such as networks of cameras where pairwise relative transformations are measured. The convergence of the method is verified in numerical simulations. [less ▲] Detailed reference viewed: 104 (1 UL)The Search for Yield: Implications to Alternative Investments Lehnert, Thorsten ; Kräussl, Roman ; Rinne, Kalle in Journal of Empirical Finance (2017), 44(-), 227-236 Detailed reference viewed: 192 (12 UL)On low complexity detection for QAM isomorphic constellations Kayhan, Farbod in Kayhan, Farbod (Ed.) On low compelxity detection for QAM isomorphic constellations (2017, December) Despite of the known gap from the Shannon's capacity, several standards are still employing QAM or star shape constellations, mainly due to the existing low complexity detectors. In this paper, we ... [more ▼] Despite of the known gap from the Shannon's capacity, several standards are still employing QAM or star shape constellations, mainly due to the existing low complexity detectors. In this paper, we investigate the low complexity detection for a family of QAM isomorphic constellations. These constellations are known to perform very close to the peak-power limited capacity, outperforming the DVB-S2X standard constellations. The proposed strategy is to first remap the received signals to the QAM constellation using the existing isomorphism and then break the log likelihood ratio computations to two one dimensional PAM constellations. Gains larger than 0.6 dB with respect to QAM can be obtained over the peak power limited channels without any increase in detection complexity. Our scheme also provides a systematic way to design constellations with low complexity one dimensional detectors. Several open problems are discussed at the end of the paper. [less ▲] Detailed reference viewed: 141 (3 UL)On a geometric framework for Lagrangian supermechanics Bruce, Andrew ; ; in Journal of Geometric Mechanics (2017), 9(4), 411-437 We re--examine classical mechanics with both commuting and anticommuting degrees of freedom. We do this by defining the phase dynamics of a general Lagrangian system as an implicit differential equation ... [more ▼] We re--examine classical mechanics with both commuting and anticommuting degrees of freedom. We do this by defining the phase dynamics of a general Lagrangian system as an implicit differential equation in the spirit of Tulczyjew. Rather than parametrising our basic degrees of freedom by a specified Grassmann algebra, we use arbitrary supermanifolds by following the categorical approach to supermanifolds. [less ▲] Detailed reference viewed: 100 (3 UL)Isolation of nucleic acids from low biomass samples: detection and removal of sRNA contaminants ; ; Kaysen, Anne et al E-print/Working paper (2017) Sequencing-based analyses of low-biomass samples are known to be prone to misinterpretation due to the potential presence of contaminating molecules derived from laboratory reagents and environments. Due ... [more ▼] Sequencing-based analyses of low-biomass samples are known to be prone to misinterpretation due to the potential presence of contaminating molecules derived from laboratory reagents and environments. Due to its inherent instability, contamination with RNA is usually considered to be unlikely. Here we report the presence of small RNA (sRNA) contaminants in widely used microRNA extraction kits and means for their depletion. Sequencing of sRNAs extracted from human plasma samples was performed and significant levels of non-human (exogenous) sequences were detected. The source of the most abundant of these sequences could be traced to the microRNA extraction columns by qPCR-based analysis of laboratory reagents. The presence of artefactual sequences originating from the confirmed contaminants were furthermore replicated in a range of published datasets. To avoid artefacts in future experiments, several protocols for the removal of the contaminants were elaborated, minimal amounts of starting material for artefact-free analyses were defined, and the reduction of contaminant levels for identification of bona fide sequences using 'ultra-clean' extraction kits was confirmed. In conclusion, this is the first report of the presence of RNA molecules as contaminants in laboratory reagents. The described protocols should be applied in the future to avoid confounding sRNA studies. [less ▲] Detailed reference viewed: 175 (2 UL)SchNet: A continuous-filter convolutional neural network for modeling quantum interactions ; ; et al in 31st Conference on Neural Information Processing Systems (NIPS 2017), Long Beach, CA, USA (2017, December) Detailed reference viewed: 366 (7 UL)Le chant choral à l’église. Une affaire de foi et d’engagement sociétal Sagrillo, Damien in Sagrillo, Damien (Ed.) Brochure 125 ans Chorale Ste Cécile Aspelt (2017) Detailed reference viewed: 70 (2 UL)On definition and inference of nonlinear Boolean dynamic networks Yue, Zuogong ; Thunberg, Johan ; et al in On definition and inference of nonlinear Boolean dynamic networks (2017, December) Network reconstruction has become particularly important in systems biology, and is now expected to deliver information on causality. Systems in nature are inherently nonlinear. However, for nonlinear ... [more ▼] Network reconstruction has become particularly important in systems biology, and is now expected to deliver information on causality. Systems in nature are inherently nonlinear. However, for nonlinear dynamical systems with hidden states, how to give a useful definition of dynamic networks is still an open question. This paper presents a useful definition of Boolean dynamic networks for a large class of nonlinear systems. Moreover, a robust inference method is provided. The well-known Millar-10 model in systems biology is used as a numerical example, which provides the ground truth of causal networks for key mRNAs involved in eukaryotic circadian clocks. In addition, as second contribution of this paper, we suggest definitions of linear network identifiability, which helps to unify the available work on network identifiability. [less ▲] Detailed reference viewed: 180 (6 UL)Combined Use of Lifecycle Management and IoT in Smart Cities ; ; et al in Combined Use of Lifecycle Management and IoT in Smart Cities (2017, December) Detailed reference viewed: 176 (7 UL)Joint and competitive caching designs in large-scale multi-tier wireless multicasting networks ; ; et al in Proc. 60th IEEE Global Communications Conference (2017, December) Detailed reference viewed: 148 (19 UL)La Grande Région Saar-Lor-Lux : Vers une suprarégionalisation transfrontalière ? Evrard, Estelle Book published by Presses Universitaires de Rennes (2017) The Greater Region Saar-Lor-Lux : Towards cross-border supraregionalisation ? Border areas are often portrayed as 'laboratories of European integration'. Beyond the discourses and symbols, what does the ... [more ▼] The Greater Region Saar-Lor-Lux : Towards cross-border supraregionalisation ? Border areas are often portrayed as 'laboratories of European integration'. Beyond the discourses and symbols, what does the concept of cross-border region actually entail? By characterising the region as the construction of an identity, a territoriality and a governance system perpetuated over time, this publication identifies and questions the specificities of these processes in the cross-border context. It distinguishes between inter- and supraregional cooperation thus questioning a border area's capacity to develop an ad hoc cross-border cooperation whose raison d'être consists in strengthening the commitments pertaining to the border area's interests. This study is underpinned by a discourse analysis and a conceptualisation of cross-border territoriality and supraregional institution. In this respect, the significance of the EGTC (European Grouping for Territorial Cooperation), a European instrument providing a legal framework for cooperation, is analysed. This issue is explored in depth using the emblematic case of the Greater Region, a border area that launched in 2008 a long-term strategy to develop a 'cross-border polycentric metropolitan region'. Composed of Lorraine (France), Luxembourg, Wallonia (Belgium), Rhineland-Palatinate and Saarland (Germany), the Greater Region constitutes one of the oldest border areas (1971) and presents the highest concentration of cross-border workers in Europe. [less ▲] Detailed reference viewed: 567 (38 UL)Locating and quantifying a transnational cultural object. Reims as a European hub for sports (1925-1940) Moreau, Sebastien Scientific Conference (2017, December) Detailed reference viewed: 52 (2 UL)On Partial-Sum Processes of ARMAX Residuals Holcblat, Benjamin ; Scientific Conference (2017, December) General and versatile results are established regarding the limit behavior of the partial-sum process of ARMAX residuals. Illustrations include ARMA with seasonal dummies, misspecified ARMAX models with ... [more ▼] General and versatile results are established regarding the limit behavior of the partial-sum process of ARMAX residuals. Illustrations include ARMA with seasonal dummies, misspecified ARMAX models with autocorrelated errors, nonlinear ARMAX models, ARMA with a structural break, a wide range of ARMAX models with infinite-variance errors, weak GARCH models and the consistency of kernel estimation of the density of ARMAX errors. Our results identify the limit distributions, and provide a general algorithm to obtain pivot statistics for CUSUM tests. [less ▲] Detailed reference viewed: 80 (5 UL) |
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