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In this paper, a novel hierarchical multirate control scheme for nonlinear discrete-time systems is presented, consisting of a robust nonlinear model predictive controller (NMPC) and a multirate sliding mode disturbance compensator (MSMDC). The proposed MSMDC acts at a faster rate than the NMPC in order to keep the system as close as possible to the nominal trajectory predicted by NMPC despite model uncertainties and external disturbances. The a priori disturbance compensation turns out to be very useful in order to improve the robustness of the NMPC controller. A dynamic input allocation between MSMDC and NMPC allows to maximize the benefits of the proposed scheme that unites the advantages of sliding mode control (strong reduction of matched disturbances, low computational burden) to those of NMPC (optimality, constraints handling). Sufficient conditions required to guarantee input-to-state stability and constraints satisfaction by the overall scheme are also provided. Copyright (c) 2014 John Wiley & Sons, Ltd.

Diversification is at the core of insurance and other financial business. It constitutes an important issue in the preparation of the new Solvency II framework for the regulation of European insurance undertakings. In this paper, we propose a conceptual framework for a legally enforceable capital and risk transfer which optimally accounts for the designated group diversification benefits. We also provide a consistent valuation principle which is compatible with any prior valuation method. This makes our framework fully flexible and universally applicable. A first simple numerical example illustrates the practicability of our proposal.

In this paper, we study tungsten oxides deposited by reactive magnetron sputtering. The total working pressure during deposition was varied in order to obtain different morphology. The effects on the electronic properties and chemical composition were studied by XPS and UPS. It was observed that, for the same argon to oxygen ratio in the gas feed, the decrease in total working pressure implies a decrease of the oxygen content in the film. In the nearly stoichiometric WO3 films, W 4f5/2 and W 4f7/2 form a distinct doublet peak. In sub-stoichiometric films, the films do not exhibit a well-resolved doublet and suggest multiple oxidation states of tungsten.The valence-band spectra of the sub-stoichiometric samples present an additional feature below the Fermi edge (~0.5 eV). This peak is assigned to W 5d1 because of the presence of W5+. It is consistent with the changes on the core-level spectra. XPS results, UPS features, and visual aspect are in agreement and suggest that the total working pressure has a strong influence on the oxygen content and therefore on the oxidation state of tungsten in the films.

In this paper, we analyze Orthogonal Frequency-Division Multiple Access and Single-Carrier Frequency Division Multiple Access as alternative physical layer schemes for the up-link of a satellite network. Both orthogonal frequency-division multiple access and single-carrier frequency division multiple access are orthogonal multicarrier modulations (MCMs). They provide a higher spectral efficiency than the single-carrier modulations employed today in satellite networks. Unfortunately, MCMs are also more vulnerable to nonlinear distortion, phase noise, and synchronization errors. This has prevented, so far, the use of MCMs in satellite uplinks, where these impairments are very critical. In our analysis, we show that a well-design MCM system can effectively provide reliable communications in satellite uplinks, even in the presence of nonlinear distortion, phase noise, and synchronization errors. Copyright (C) 2014 John Wiley & Sons, Ltd.

The joint bilateral filter is a variant of the standard bilateral filter, where the range kernel is evaluated using\ud a guidance signal instead of the original signal. It has been successfully applied to various image processing\ud problems, where it provides more flexibility than the standard bilateral filter to achieve high quality results. On\ud the other hand, its success is heavily dependent on the guidance signal, which should ideally provide a robust\ud estimation about the features of the output signal. Such a guidance signal is not always easy to construct. In this\ud paper, we propose a novel mesh normal filtering framework based on the joint bilateral filter, with applications\ud in mesh denoising. Our framework is designed as a two-stage process: first, we apply joint bilateral filtering to\ud the face normals, using a properly constructed normal field as the guidance; afterwards, the vertex positions are\ud updated according to the filtered face normals. We compute the guidance normal on a face using a neighboring\ud patch with the most consistent normal orientations, which provides a reliable estimation of the true normal even\ud with a high-level of noise. The effectiveness of our approach is validated by extensive experimental results

In this paper a new approach for fixed-structure H2 controller design in terms of solutions to a set of linear matrix inequalities are given. Both discrete- and continuous-time single-input single-output (SISO) time- invariant systems are considered. Then the results are extended to systems with polytopic uncertainty. The presented methods are based on an inner convex approximation of the non-convex set of fixed-structure H2 controllers. The designed procedures initialized either with a stable polynomial or with a stabilizing controller. An iterative procedure for robust controller design is given that converges to a suboptimal solution. The monotonic decreasing of the upper bound on the H2 norm is established theoretically for both nominal and robust controller design.

In this paper, an approach for information systems reverse engineering is proposed and applied. The aim is to support a unified perspective to the reverse engineering process of both data and software. At the state of the art, indeed, many methods, techniques, and tools for software reverse engineering have been proposed to support program comprehension, software maintenance, and software evolution. Other approaches and tools have been proposed for data reverse engineering, with the aim, for example, to provide complete and up-to-date documentation of legacy databases. However, the two engineering communities often worked independently, and very few approaches addressed the reverse engineering of both data and software as information system's constituencies. Hence, a higher integration is needed to support a better co-evolution of databases and programs, in an environment often characterized by high availability of data and volatility of information flows. Accordingly, the approach we propose leverages the detection of object-relational mapping design patterns to build a conceptual schema of the software under analysis. Then, the conceptual schema is mapped to the domain model of the system, to support the design of the evolution of the information system itself. The approach is evaluated on two large-scale open-source enterprise applications. Copyright (c) 2014 John Wiley & Sons, Ltd.

This paper provides a unifying approach for valuing contingent claims on a portfolio of credits, such as collateralized debt obligations (CDOs). We introduce the defaultable (T, x)-bonds, which pay one if the aggregated loss process in the underlying pool of the CDO has not exceeded x at maturity T, and zero else. Necessary and sufficient conditions on the stochastic term structure movements for the absence of arbitrage are given. Background market risk as well as feedback contagion effects of the loss process are taken into account. Moreover, we show that any exogenous specification of the volatility and contagion parameters actually yields a unique consistent loss process and thus an arbitrage-free family of (T, x)-bond prices. For the sake of analytical and computational efficiency we then develop a tractable class of doubly stochastic affine term structure models.

Carbon-electrode dielectrophoresis (carbon-DEP) is demonstrated here as an alternative to more traditional DEP techniques. Carbon-DEP combines advantages of metal-electrode and insulator-based DEP by using low-cost fabrication techniques and low voltages for particle manipulation. The use of 3-D electrodes is proved to yield significant advantages over the use of traditional planar electrodes. This paper details the fabrication of dense arrays of tall high aspect ratio carbon electrodes on a transparent fused-silica substrate. The shrinkage of the SU-8 structures during carbonization is characterized and a design tool for future devices is provided. Applications of carbon electrodes in DEP are then detailed and include particle positioning, high-throughput filtering and cell focusing using positive-DEP. Manipulated cells include Saccharomyces cerevisiae and Drosophila melanogaster. The advantages and disadvantages of carbon-DEP are discussed at the end of this work.

The misuse of Personal Protective Equipment results in health risk among smallholders in developing countries, and education is often proposed to promote safer practices. However, evidence point to limited effects of education. This paper presents a System Dynamics model which allows the identification of risk-minimizing policies for behavioural change. The model is based on the IAC framework and survey data. It represents farmers’ decision-making from an agent-oriented standpoint. The most successful intervention strategy was the one which intervened in the long term, targeted key stocks in the systems and was diversified. However, the results suggest that, under these conditions, no policy is able to trigger a self sustaining behavioural change. Two implementation approaches were suggested by experts. One, based on constant social control, corresponds to a change of the current model’s parameters. The other, based on participation, would lead farmers to new thinking, i.e. changes in their decision-making structure.

Silver nanoparticles embedded in a dielectric material have strong scattering properties under light illumination, due to localized surface plasmons. This effect is a potential way to achieve light trapping in thin-film solar cells. In this paper we study light scattering properties of nanoparticles on glass and ZnO, and on silver coated with ZnO, which represent the back reflector of a solar cell. We find that large nanoparticles embedded in the dielectric at the back contact of amorphous silicon solar cells lead to a remarkable increase in short circuit current of 20% compared to co-deposited cells without nanoparticles. This increase is strongly correlated with the enhanced cell absorption in the long wavelengths and is attributed to localized surface plasmons. We also discuss the electrical properties of the cells. Copyright # 2010 John Wiley & Sons, Ltd.

Energy geostructures are rapidly gaining acceptance around the world; they represent a renewable and clean source of energy that can be used for the heating and cooling of buildings and for de-icing of infrastructures. This technology couples the structural role of geostructures with the energy supply, using the principle of shallow geothermal energy. The geothermal energy exploitation represents an additional thermal loading, seasonally cyclic, which is imposed on the soil and the structure itself. Because the primary role of the piles is the stability of the superstructure, this aspect needs to be ensured even in the presence of the additional thermal load. The goal of this paper is to numerically investigate the behaviour of energy pile foundations during heating–cooling cycles. For this purpose, the finite element method is used to simulate both a single and a group of energy piles. The piles are subjected to a constant mechanical load and a seasonally cyclic thermal load over several years, imposed in terms of injected–extracted thermal power. The soil and the pile–soil interface behaviours are reproduced using a thermoelastic-thermoplastic constitutive model. The thermal-induced stresses inside the piles and the additional displacements of the foundations are discussed. The group model is used to investigate the interactions between the piles during thermo-mechanical loading. The presented results are specific to the studied cases but lead to the conclusion that both the thermalinduced displacements and stresses, despite being acceptable under normal working conditions, deserve to be taken into account in the geotechnical design of energy piles.

The paper describes and compares the performance of two options for numerically representing the surface tension force in combination with the level set interface-tracking method. In both models, the surface tension is represented as a body force, concentrated near the interface, but the technical implementation is different: the first model is based on a traditional level set approach in which the force is distributed in a band around the interface using a regularized delta function, whereas in the second, the force is partly distributed in a band around the interface and partly localized to the actual computational cells containing the interface. A comparative Study, involving analysis of several two-phase flows with moving interfaces, shows that in general the two surface tension models produce results of similar accuracy. However, in the particular case of merging and pinching-off of interfaces, the traditional level set model of surface tension produces an error that results in non-converging solutions for film-like interfaces (i.e. ones involving large contact areas). In contrast, the second model, based on the localized representation of the surface tension force, displays consistent first-order convergence.

This paper analyses the relationships between different service level agreement (SLA) components, that is, the different types of quality metrics employed by infrastructure and service providers. We propose that the quality of network economics (QoNE) be used to evaluate the quality of a network path for a given SLA model. Our evaluation indicates the usefulness of the QoNE metric, and it provides a new mechanism for the networking community to address network design problems when incorporating new challenges, such as the Internet of Things. We show how the proposed model can be implemented in software-defined network architecture applicable to networking technologies that include the interconnection of autonomous systems.

Microfabricated fuel cell systems have the potential to outperform batteries for man-portable power generation. Because many electronic devices operate at various loads, with frequent start-ups and shut-downs, transient aspects are highly important and must be considered thoroughly. In this paper, the focus is on the optimal start-up of microfabricated fuel cell systems using numerical open-loop optimal control. For start-up purposes, a small rechargeable battery is used to provide the energy needed to heat up the fuel cell stack and meet the power demand when the fuel cell is unavailable or can only satisfy part of the demand. The objective of the start-up problem is to bring the system to a desired operating point with a minimal total mass of the system (battery and fuels), while meeting the nominal power demand at any time and satisfying the operational restrictions. The model for the fuel cell stack consists of partial differential-algebraic equations with multiple time scales and numerical techniques that exploit a separation of these time scales are used for efficient and reliable integration of the state and sensitivity equations. A case study of a microfabricated power generation system employing a high-temperature solid-oxide fuel cell and using ammonia and butane as fuels is presented. Copyright © 2010 John Wiley & Sons, Ltd.

In this paper, we present a way of utilizing thin and conformal overlayer of titanium dioxide on insulating mesoporous template as a photoanode for dye-sensitized solar cells (DSC). Different thicknesses of TiO2 ranging from 1 nm to 15 nm are deposited on the surface of the template by atomic layer deposition (ALD) technique. This systematic study helps unravelling the minimum critical thickness of the TiO2 overlayer required to transport the photogenerated electrons efficiently. A merely 6 nm thick TiO2 film on a 3 μm mesoporous insulating substrate is shown to transport 8 mA/cm2 of photocurrent density along with ~900 mV of open-circuit potential when using our standard donor-π-acceptor sensitizer and Co(bipyridine) redox mediator.

Stress wave attenuation across fractured rock masses is a great concern of underground structure safety. This paper presents an analytical study on wave attenuation across parallel fractures at arbitrary incidence angles, where multiple reflections occurring between fractures are taken into account. Combined with displacement discontinuous model, plane wave analysis and propagator matrix method are applied to develop relations between the first layer and the nth layer with respect to potential amplitudes or displacements and stresses in matrix form. With initial and boundary conditions for different scenarios, potential amplitudes in any layer or displacements and stresses at any point can be obtained by solving corresponding matrixes. After parametric studies, it is found that parameters including incidence angle, normalized fracture stiffness, number of fractures, and fracture spacing have obvious effects on wave attenuation across parallel fractures.

How Do We Communicate Model Performance? The process of model performance evaluation is of primary importance, not only in the model development and calibration process, but also when communicating the results to other researchers and to stakeholders. The basic ‘rule’ is that every modelling result should be put into context, for example, by indicating the model performance using appropriate indicators, and by highlighting potential sources of uncertainty, and this practice has found its entry into the large majority of papers and conference presentations. While the question of how to communicate the performance of a model to potential end-users is currently receiving increasing interest (e.g. Pappenberger and Beven, 2006), we–as well as many other colleagues–observe regularly that researchers take much less care when communicating model performance amongst ourselves. We seem to assume that we are speaking about familiar performance concepts and that they have comparable significance for various types of model applications and case studies. In doing so, we do not pay sufficient attention to making clear what the values represented by our performance measures really mean. Even concepts as simple as the bias between an observed and a simulated time series need to be put into proper context: whereas a 10% bias in simulation of simulated discharge may be unacceptable in a climate change impact assessment, it may be of less concern in the context of real-time flood forecasting. While some performance measures can have an absolute meaning, such as the common measure of linear correlation, the vast majority of performance measures, and in particular quadratic-error-based measures, can only be properly interpreted when viewed in the context of a reference value (..)

While elastic optical network technologies have emerged as promising solutions for future ultra-high-speed optical transmission, the unavoidable spectral fragmentation problem that appears in such networks significantly degrades their performance. In light of this, spectral defragmentation technologies have been introduced in elastic optical networks, aiming to increase the spectrum utilisation. During the defragmentation operation, the available fragmented spectrum bands are consolidated by reallocating existing connections, either re-routing them along alternative routes and/or re-tuning them onto different spectrum portions. Obviously, spectral defragmentation increases network complexity and cost. Therefore, it is highly desirable to limit its application as much as possible, while keeping network performance within acceptable margins. In this paper, we focus on analyzing the correlation between the optimal (i.e. minimum) spectrum defragmentation periodicity in the network with the granularity of the supported traffic. For this purpose, we initially introduce a novel algorithm for efficient spectrum defragmentation. The proposed algorithm aims to consolidate the available fibre spectrum as much as possible, while limiting the number of reallocated active connections. Then, supported on extensive simulation results, we show how spectral defragmentation periodicity can be effectively configured by having knowledge of the offered traffic granularity.

Hierarchically porous transparent silica coatings combine large specific surface area with enhanced pore accessibility for optical biosensing. This paper describes a versatile approach to fabricate optically transparent silica coatings with multiscale porosity. Thin films (around 1 mu m in thickness) of an aqueous suspension of primary silica aggregates form a mesoporous, interconnected matrix, and sacrificial polymer particles template well-defined, discrete macropores with high structural integrity. The total surface area achieved is around 200 m(2) g(-1) with mesopore sizes of 20-40 nm and macropores of 250 nm, with a total porosity of 84%. The macro/meso dual range of porosity allows enhanced biocatalyst loadings of l-lactate dehydrogenase for detection of lactate. The functionalized films showed a linear response within the range of interest of 1-20 x 10(-3) m of lactate. These biosensing coatings therefore strongly enhance sensitivity, speed and reliability of optically based lactate detection as compared to classical thin films with monomodal mesopore structure. Particle-based simulations and experiments reveal that both the location and connectivity of the macropores control the biosensing performance. The coatings and procedure presented here are versatile, scalable, inexpensive, and are therefore compatible with a wide range of deposition techniques suitable for industrial and health care applications.

We study a problem posed in Bjork and Christensen (1999): does there exist any nontrivial interest rate model which is consistent with the Nelson-Siegel family? They show that within the HJM framework with deterministic volatility structure the answer is no.In this paper we give a generalized version of this result including stochastic volatility structure. For that purpose we introduce the class of consistent state space processes, which have the property to provide an arbitrage-free interest rate model when representing the parameters of the Nelson-Siegel family. We characterize the consistent state space Ito processes in terms of their drift and diffusion coefficients. By solving an inverse problem we find their explicit form. It turns out that there exists no nontrivial interest rate model driven by a consistent state space Ito process.

Novel memory-efficient Arnoldi algorithms for solving matrix polynomial eigenvalue problems are presented. More specifically, we consider the case of matrix polynomials expressed in the Chebyshev basis, which is often numerically more appropriate than the standard monomial basis for a larger degree d. The standard way of solving polynomial eigenvalue problems proceeds by linearization, which increases the problem size by a factor d. Consequently, the memory requirements of Krylov subspace methods applied to the linearization grow by this factor. In this paper, we develop two variants of the Arnoldi method that build the Krylov subspace basis implicitly, in a way that only vectors of length equal to the size of the original problem need to be stored. The proposed variants are generalizations of the so-called quadratic Arnoldi method and two-level orthogonal Arnoldi procedure methods, which have been developed for the monomial case. We also show how the typical ingredients of a full implementation of the Arnoldi method, including shift-and-invert and restarting, can be incorporated. Numerical experiments are presented for matrix polynomials up to degree 30 arising from the interpolation of nonlinear eigenvalue problems, which stem from boundary element discretizations of PDE eigenvalue problems. Copyright (C) 2013 John Wiley & Sons, Ltd.

This paper describes the relationship between the statistics of bed load transport flux and the timescale over which it is sampled. A stochastic formulation is developed for the probability distribution function of bed load transport flux, based on the Ancey et al. (2008) theory. An analytical solution for the variance of bed load transport flux over differing sampling timescales is presented. The solution demonstrates that the timescale dependence of the variance of bed load transport flux reduces to a three-regime relation demarcated by an intermittency timescale (t(I)) and a memory timescale (t(c)). As the sampling timescale increases, this variance passes through an intermittent stage (<> t(c)). We propose a dimensionless number (Ra) to represent the relative strength of fluctuation, which provides a common ground for comparison of fluctuation strength among different experiments, as well as different sampling timescales for each experiment. Our analysis indicates that correlated motion and the discrete nature of bed load particles are responsible for this three-regime behavior. We use the data from three experiments with high temporal resolution of bed load transport flux to validate the proposed three-regime behavior. The theoretical solution for the variance agrees well with all three sets of experimental data. Our findings contribute to the understanding of the observed fluctuations of bed load transport flux over monosize/multiple-size grain beds, to the characterization of an inherent connection between short-term measurements and long-term statistics, and to the design of appropriate sampling strategies for bed load transport flux.

BACKGROUND AND PURPOSE Narcolepsy is an uncommon hypothalamic disorder of presumed autoimmune origin that usually requires lifelong treatment. This paper aims to provide evidence-based guidelines for the management of narcolepsy in both adults and children. METHODS The European Academy of Neurology (EAN), European Sleep Research Society (ESRS), and European Narcolepsy Network (EU-NN) nominated a task force of 18 narcolepsy specialists. According to the EAN recommendations, 10 relevant clinical questions were formulated in PICO format. Following a systematic review of the literature (performed in Fall 2018 and updated in July 2020) recommendations were developed according to the GRADE approach. RESULTS A total of 10,247 references were evaluated, 308 studies were assessed and 155 finally included. The main recommendations can be summarized as follows: (i) excessive daytime sleepiness (EDS) in adults-scheduled naps, modafinil, pitolisant, sodium oxybate (SXB), solriamfetol (all strong); methylphenidate, amphetamine derivatives (both weak); (ii) cataplexy in adults-SXB, venlafaxine, clomipramine (all strong) and pitolisant (weak); (iii) EDS in children-scheduled naps, SXB (both strong), modafinil, methylphenidate, pitolisant, amphetamine derivatives (all weak); (iv) cataplexy in children-SXB (strong), antidepressants (weak). Treatment choices should be tailored to each patient's symptoms, comorbidities, tolerance and risk of potential drug interactions. CONCLUSION The management of narcolepsy involves non-pharmacological and pharmacological approaches with an increasing number of symptomatic treatment options for adults and children that have been studied in some detail.

This paper investigates the effect of the gravity framing system on the overstrength and collapse risk of steel frame buildings with perimeter special moment frames (SMFs) designed in North America. A nonlinear analytical model that simulates the pinched hysteretic response of typical shear tab connections is calibrated with past experimental data. The proposed modeling approach is implemented into nonlinear analytical models of archetype steel buildings with different heights. It is found that when the gravity framing is considered as part of the analytical model, the overall base shear strength of steel frame buildings with perimeter SMFs could be 50% larger than that of the bare SMFs. This is attributed to the gravity framing as well as the composite action provided by the concrete slab. The same analytical models (i) achieve a static overstrength factor, Ωs larger than 3.0 and (ii) pass the collapse risk evaluation criteria by FEMA P695 regardless of the assigned total system uncertainty. However, when more precise collapse metrics are considered for collapse risk assessment of steel frame buildings with perimeter SMFs, a tolerable probability of collapse is only achieved in a return period of 50years when the perimeter SMFs of mid-rise steel buildings are designed with a strong-column/weak-beam ratio larger than 1.5. The concept of the dynamic overstrength, Ωd is introduced that captures the inelastic force redistribution due to dynamic loading. Steel frame buildings with perimeter SMFs achieve a Ωd>3 regardless if the gravity framing is considered as part of the nonlinear analytical model representation. © 2014 John Wiley & Sons, Ltd.

Maximising the health of the developing fetus and the infant until the age of two (the first thousand days) provides benefits for the child’s physical, emotional and cognitive development and their subsequent health as an adult. This paper explains how with an injection of $A400 million into the Australian health and social care system this can be achieved.

This paper reports on the cell uptake and trafficking properties of a series of non-covalent polymer-drug conjugates. These nanomedicines are composed of a poly(N-(2-hydroxypropyl)methacrylamide) backbone functionalized with multiple copies of a drug. The drug moieties are attached to the polymer via a non-covalent, so called coiled coil motif, which is formed by heterodimerization of two complementary peptide strands, one of which is attached to the polymer carrier and the other to the drug. Cytotoxicity and FACS experiments, which were carried out with model anticancer drug or fluorophore conjugates, provided insight into the cell uptake and trafficking behavior of these conjugates.

The paper presents a review of active set (AS) algorithms that have been deployed for implementation of fast model predictive control (MPC). The main purpose of the survey is to identify the dominant features of the algorithms that contribute to fast execution of online MPC and to study their influence on the speed. The simulation study is conducted on two benchmark examples where the algorithms are analyzed in the number of iterations and in the workload per iteration. The obtained results suggest directions for potential improvement in the speed of existing AS algorithms.

Nowadays, nanoporous films are widely employed in biochemical applications or in opto-photonic devices such as displays, solar cells, or light-guiding systems. In particular, the technological feasibility of nanoporous layers with low refractive indices has recently enabled the development of high-efficiency anti-reflection coatings. In this paper, we report on hybrid polymer nanoporous films that can be fabricated in a single coating step with an industrial aqueous-based method on very large surfaces. Both high transparency and low refractive index are simultaneously achieved over the entire visible spectrum. We eventually demonstrate the potential of such films for broadband AR applications by combining them in a graded-index multilayer that reduces the surface reflectivity of a polymer substrate from 10% to few ‰.

Confluences with low discharge and momentum ratios, where narrow steep tributaries with high sediment load join a wide low-gradient main channel that provides the main discharge, are often observed in high mountain regions such as in the upper- Rhone river catchment in Switzerland. Few existing studies have examined the hydro-morphodynamics of this type of river confluence while considering sediment discharge in both confluent channels. This paper presents the evolution of the bed morphology and hydrodynamics as observed in an experimental facility with a movable bed. For that purpose, one experiment was carried out in a laboratory confluence with low discharge and momentum ratios, where constant sediment rates were supplied to both flumes. During the experiment, bed topography and water surface elevations were systematically recorded. When the bed topography reached a steady state (so-called equilibrium) and the outgoing sediment rate approximated the incoming rate, flow velocity was measured at 12 different points distributed throughout the confluence, and the grain size distribution of the bed surface was analyzed. Typical morphodynamic features of discordant confluences such as a bank-attached bar and a flow deflection zone are identified in this study. Nevertheless, the presence of a marked scour hole in the discordant confluence and distinct flow regimes for the tributary and main channel, differ from results obtained in previous studies. Strong acceleration of the flow along the outer bank of the main channel is responsible for the scour hole. This erosion is facilitated by the sediment discharge into the confluence from the main channel which inhibits bed armoring in this region. The supercritical flow regime observed in the tributary is the hydrodynamic response to the imposed sediment rate in the tributary. Copyright © 2015 John Wiley & Sons, Ltd.

Crowd animation is a topic of high interest which offers many challenges. One of the most important is the trade-off between rich, realistic behaviors, and computational costs. To this end, much effort has been put into creating variety in character representation and animation. Nevertheless, one aspect still lacking realism in virtual crowd characters resides in their attention behaviors. In this paper, we propose a framework to add gaze attention behaviors to crowd animations. First, We automatically extract interest points from character or object trajectories in pre-existing animations. For a given character, We assign a set of elementary scores based on parameters such as distance or speed to all other characters or objects in the scene. We then combine these subscores in all overall scoring function. The scores obtained from this function form a set of gaze constraints that determine where and when each character should look. We finally enforce these constraints With all optimized dedicated gaze Inverse Kinematics (IK) solver. It first computes Me displacement maps for the constraints to be satisfied. It then smoothly propagates these displacements over all automatically defined number of frames. We demonstrate the efficiency of our method and our visually convincing results through various examples. Copyright (C) 2009 John Wiley & Sons, Ltd.

In the recent years, the heterojunction solar cells based on quantum dots (QDs) have attracted attention due to strong light absorbing characteristics and the size effect on the bandgap tuning. This paper reports on the kinetics of interfacial charge separation of PbS QDs/(001) TiO2 nanosheets heterojunction solar cells. PbS QDs are deposited using a bifunctional linker molecule on two different TiO2 films, i.e., TiO2 nanosheets (with 001 dominant exposed facet) and TiO2 nanoparticles (with 101 dominant exposed facet). Upon bandgap excitation, electrons are transferred from the PbS QDs conduction band to the lower lying conduction band of TiO2. Based on the ultrafast pump-probe laser spectroscopy technique, the kinetics of charge separation is scrutinized at the PbS/TiO2 interface. The interfacial charge separation at PbS/TiO2 nanosheets films made of (001) dominant exposed facets is five times faster than that on (101) dominant exposed facets TiO2 nanoparticles. The quantum yields for charge injection are higher for the (001) TiO2 nanosheets than the (101) TiO2 nanoparticles due to enhanced interfacial interaction with (001) surface compared to the (101) nanoparticles. The superior interfacial charge separation at PbS/(001) nanosheets respect to PbS/(101) nanoparticles is consistent with the higher photocurrent and enhanced power conversion efficiency in the PbS QDs/(001) TiO2 heterojunction solar cell. The use of (001) TiO2 nanosheets can be a better alternative to conventional mesoporous TiO2 films in QD heterojunction solar cells and perovskites-based heterojunction solar cells.

This paper addresses radio frequency identification (RFID) authentication and ownership transfer in offline scenarios. Four typical related works are reviewed in detail. A series of shortcomings and vulnerabilities of them are pointed out. A new RFID authentication protocol based on a novel tag-owner-assisting architecture is proposed, making a tag's owner an essential participant of the RFID authentication process. The proposed protocol is distinguished from existing works in providing ownership transfer, access control, and mutual authentication without any centralized database neither on a backend server nor in a reader. The security of the proposed protocol is verified by using automated validation of Internet security protocols and applications tool. The proposed protocol is server-less, simple, scalable, untraceable, and device-independent. These features are simultaneously achieved in a single RFID authentication protocol for the first time. Copyright (c) 2014 John Wiley & Sons, Ltd.

This is the peer reviewed version of the following article: Montero R, Agraz F, Pagès A, Perelló J, Spadaro S. SDN‐based parallel link discovery in optical transport networks. Trans Emerging Tel Tech. 2018;e3512. https://doi-org.recursos.biblioteca.upc.edu/10.1002/ett.3512, which has been published in final form at https://doi-org.recursos.biblioteca.upc.edu/10.1002/ett.3512. This article may be used for non-commercial purposes in accordance with Wiley Terms and Conditions for Self-Archiving. The use of optical technologies in modern network scenarios has increased in the last decade, mostly due to their support in crucial networking topics (ie, bandwidth and scalability). In parallel, these scenarios have also experienced the emergence of a new paradigm recognized as software-defined networking (SDN), which bases on the decoupling of forwarding and control functions, with aims to provide a more efficient way to manage network resources compared to legacy networking architectures. As both SDN and optical technologies are constantly being introduced in different networking scenarios (eg, data centers, metro, and access networks), their coexistence becomes a must. In this matter, it is important to notice that SDN was initially designed for electronic-based networks; hence, its support for optical technologies is still at an early stage. Consequently, integration of both solutions still requires research efforts by the community. In this paper, we present a mechanism to address topology discovery in wavelength-switching optical transport networks (OTNs). In particular, we discuss the importance of the topology discovery function and analyse the proposed mechanism, which bases itself on the use of wavelength-specific signaling tones as link-binding data to provide preservice parallel link discovery in OTNs. Furthermore, we validate the method experimentally against an emulated OTN testbed with two different setups and compare the results to our previous work on this subject, achieving substantial reductions in the total topology discovery time.

To identify physical parameters of a large structural system, the computational challenges in dealing with a large number of unknowns are formidable. A divide-and-conquer approach is often required to partition the structural system into many substructures, each with much lesser unknowns for more accurate and efficient identification. Furthermore, in view of the ill-conditioned nature of inverse analysis, it is highly beneficial to adopt nongradient-based search methods such as genetic algorithm (GA). To this end, this paper presents a GA-based substructural identification strategy for large structural systems. As compared with some recent work on substructural identification, the proposed strategy presents two significant improvements: (i) the use of acceleration measurement to directly account for interaction between substructures without approximation of interface force; and (ii) the use of an improved identification method based on multi-feature GA. In numerical simulations, the mass, damping, and stiffness parameters of a 100-storey shear building, involving 202 unknowns, are identified with very good accuracy (mean error of less than 3%) based on incomplete acceleration measurements with 10% noise. In addition, an experimental study on a 10-storey small-scale steel frame further validates the superior performance of the proposed strategy over complete structural identification.

Kinetic modeling of batch reactions monitored by in-situ spectroscopy has been shown to be a helpful method for developing a complete understanding of reaction systems. Much work has been done to demonstrate the ability to model dissolution, reaction and crystallization processes separately, however little has been done in terms of combining all of these into one comprehensive kinetic model. This paper demonstrates the integration of models of dissolution, temperature-dependent solubility and unseeded crystallization driven by cooling into a comprehensive kinetic model describing the evolution of a slurry reaction monitored by in-situ ATR UV/Vis spectroscopy. The model estimates changes in the volume of the dissolved fraction of the slurry by use of the partial molar volume of the dissolved species that change during the course of reagent addition, dissolution, reaction and crystallization. The comprehensive model accurately estimates concentration profiles of dissolved and undissolved components of the slurry and thereby, the degree of undersaturation and supersaturation necessary for estimation of the rates of dissolution and crystallization. Results were validated across two subsequent batches via offline HPLC measurements.

The existence of the growth optimal portfolio (GOP), also known as the Kelly portfolio, is vital for a financial market to be meaningful. The GOP, if it exists, is uniquely determined by the market parameters of the primary security accounts. However, markets may develop and new security accounts become tradable. What happens to the GOP if the original market is extended? In this paper we provide a complete characterization of market extensions which are consistent with the existence of a GOP. We show that a three fund separation theorem applies for the extended GOP. This includes, in particular, the introduction of a locally risk free security, the savings account. We give necessary and sufficient conditions for a consistent exogenous specification of the prevailing short rates.

Fragility functions are commonly used in performance-based earthquake engineering for predicting the damage state of a structure subjected to an earthquake. This process often involves estimating the structural damage as a function of structural response, such as the story drift ratio and the peak floor absolute acceleration. In this paper, a new framework is proposed to develop fragility functions to be used as a damage classification/prediction method for steel structures based on a wavelet-based damage sensitive feature (DSF). DSFs are often used in structural health monitoring as an indicator of the damage state of the structure, and they are easily estimated from recorded structural responses. The proposed framework for damage classification of steel structures subjected to earthquakes is demonstrated and validated with a set of numerically simulated data for a four-story steel moment-resisting frame designed based on current seismic provisions. It is shown that the damage state of the frame is predicted with less variance using the fragility functions derived from the wavelet-based DSF than it is with fragility functions derived from an alternate acceleration-based measure, the spectral acceleration at the first mode period of the structure. Therefore, the fragility functions derived from the wavelet-based DSF can be used as a probabilistic damage classification model in the field of structural health monitoring and an alternative damage prediction model in the field of performance-based earthquake engineering. © 2011 John Wiley & Sons, Ltd.

In this paper we analyse the optimal infinite-horizon advertising policy of a monopolist firm in a market for durable goods, based on classic models by Vidale–Wolfe (Oper. Res. 1957; 5(3):370–381) and Nerlove–Arrow (Economica 1962; 29 (114):129–142). A set of necessary conditions for optimality generalizing previous results is provided for the resulting non-convex system. In addition, we establish local (and in some cases global) asymptotic convergence of an optimal trajectory towards the unique optimal steady state.

In a paper entitled "Stripy Nanoparticles Revisited", Levy and co-workers contest the interpretation of scanning tunneling microscopy images of monolayer protected gold nanoparticles that our group has presented. We show that the two arguments they use are based on flawed assumptions and contradict each other. We also show new evidence for the existence of stripe-like domains on mixed monolayer-coated gold nanoparticles. Copyright © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

This paper provides a coherent method for scenario aggregation addressing model uncertainty. It is based on divergence minimization from a reference probability measure subject to scenario constraints. An example from regulatory practice motivates the definition of five fundamental criteria that serve as a basis for our method. Standard risk measures, such as value-at-risk and expected shortfall, are shown to be robust with respect to minimum divergence scenario aggregation. Various examples illustrate the tractability of our method.

This study presents the vortex structure and numerical instability increase occurring when the level of elasticity is enhanced in inertial flows in planar contraction configuration for finitely extensible nonlinear elastic model by Peterlin (FENE-P) fluid . The re-entrant corner effect on corner vortices is also considered. The calculations are performed using extended matrix logarithm formulation described in a previous paper: A. Jafari et al. A new extended matrix logarithm formulation for the simulation of viscoelastic fluids by spectral elements. Computer & Fluids 2010; 39(9):1425-1438. In that reference, the proposed algorithm has been tested for simple geometry such as Poiseuille flow. In this study, we are interested in the capability of this algorithm for more complex geometry. This formulation helps to reach higher values of the Weissenberg number when compared with the classical one. Copyright (c) 2015John Wiley & Sons, Ltd.

In gravel bed rivers, bed load transport exhibits considerable variability in time and space. Recently, stochastic bed load transport theories have been developed to address the mechanisms and effects of bed load transport fluctuations. Stochastic models involve parameters such as particle diffusivity, entrainment, and deposition rates. The lack of hard information on how these parameters vary with flow conditions is a clear impediment to their application to real-world scenarios. In this paper, we determined the closure equations for the above parameters from laboratory experiments. We focused on shallow supercritical flow on a sloping mobile bed in straight channels, a setting that was representative of flow conditions in mountain rivers. Experiments were run at low sediment transport rates under steady nonuniform flow conditions (i.e., the water discharge was kept constant, but bed forms developed and migrated upstream, making flow nonuniform). Using image processing, we reconstructed particle paths to deduce the particle velocity and its probability distribution, particle diffusivity, and rates of deposition and entrainment. We found that on average, particle acceleration, velocity, and deposition rate were responsive to local flow conditions, whereas entrainment rate depended strongly on local bed activity. Particle diffusivity varied linearly with the depth-averaged flow velocity. The empirical probability distribution of particle velocity was well approximated by a Gaussian distribution when all particle positions were considered together. In contrast, the particles located in close vicinity to the bed had exponentially distributed velocities. Our experimental results provide closure equations for stochastic or deterministic bed load transport models.

Building upon Bussgang's theorem, we present a new expression for the total degradation (TD) in OFDM systems. This novel expression is applicable to any high power amplifier (HPA) model. It enables a significant speed-up in computing TD, because it avoids end-to-end system simulations. As a consequence, it simplifies the evaluation of TD as a function of the back-off, yielding a more accurate evaluation of the optimum HPA back-off.Summary In this paper, building upon Bussgang's theorem, we present a new expression for the total degradation (TD) in OFDM systems. This novel expression is applicable to any high power amplifier (HPA) model. In case of ideal clipping HPA model and for particular realizations of Rapp and Saleh HPA models, it and can be expressed in closed form. It enables a significant speed-up in computing TD, because it avoids end-to-end system simulations. As a consequence, it simplifies the evaluation of TD as a function of the back-off, yielding a more accurate evaluation of the optimum HPA back-off (i.e., the back-off value that minimizes TD). Numerical results show a perfect agreement between the proposed analytical framework and the Monte Carlo simulation results.

The combination of evidence from independent studies has a curious history. The origins reach back at least to the beginning of the 20th century. Since the mid-1970s, meta-analysis has become popular in several fields, among them medical statistics and the behavioural sciences. The most widely used procedures were perfected in early papers, and subsequently, a kind of groupthink has taken hold of meta-analysis. This explains the need for a review in a statistics journal, destined for a statistical audience. Meta-analysis is not a hot research topic among graduate students in statistics, and by writing this article, we hope to change this. We wish to point out the shortcomings of the mainstream view and exhibit some of the open problems that await the attention of statistical researchers. A host of competent reviews of meta-analysis have been published, and several book-length treatments are also available. We have listed many of these in the bibliography but cannot guarantee completeness.

Clustering and classification of replicated data is often performed using classical techniques that inappropriately treat the data as unreplicated, or by complex modern ones that are computationally demanding. In this paper, we introduce a simple approach based on a spike-and-slab mixture model that is fast, automatic, allows classification, clustering and variable selection in a single framework, and can handle replicated or unreplicated data. Simulation shows that our approach compares well with other recently proposed methods. The ideas are illustrated by application to microarray and metabolomic data. The Canadian Journal of Statistics 43: 157-175; 2015 (c) 2015 Statistical Society of Canada

Europium and terbium trisdipicolinate complexes are inkjet printed onto paper with commercially available desktop inkjet printers. Together with a commercial blue luminescent ink, the red-emitting luminescent ink containing europium and the green-emitting luminescent ink containing terbium are used to reproduce accurate full color images that are invisible under white light and appear under a 254 nm UV light. Such invisible luminescent images are attractive anti-counterfeiting security features. The luminescent prints have a color range (gamut) nearly as wide as the gamut of a standard sRGB display. The gamut of the luminescent prints is determined by relying on a simple model predicting the relative spectral radiant emittances of any printed luminescent color halftone. The model is also used to establish the correspondence between the surface coverages of the printed luminescent inks and the emitted color of these luminescent halftones. The accuracy of the spectral prediction model is very good and can be rationalized by the absence of quenching when the luminescent lanthanide complexes are printed in superposition with the other luminescent materials.

Mountain passes are potentially advantageous sites for the deployment of wind turbines because of road links and electrical transmission infrastructure. However, relatively little is known about wind characteristics and turbine response in these environments. Using hub height wind data from a mountain pass in Switzerland, this paper discusses the causes of the observed pass winds and how a generic wind turbine might perform in those conditions. During 3months of winter measurements, the winds in the pass showed signatures of forcing by regional pressure gradients rather than local cooling or heating. Turbulence intensity was often less than 10%, and the magnitude of the wind shear power law exponent was less than 0.1. To understand the impact of pass winds on a wind turbine, we simulated a Wind Partnership for Advanced Component Technologies 1.5MW wind turbine using the Fatigue, Aerodynamics, Structures, and Turbulence(FAST) aeroelastic simulator , forced by artificial wind fields of varying turbulence intensity and shear generated by the turbulence simulator TurbSim. We used the turbine simulation data to train a regression model that is used to predict the turbine response to the pass wind time series. Results showed that depending on long-term wind characteristics, wind turbines in the pass may perform differently than predicted using a power curve derived from test measurements at another location. This method of generating site-specific energy capture predictions could be combined with long-term wind resource data and specific turbine models to better predict the energy production and turbine loads at this, or any other site. Copyright (c) 2013 John Wiley & Sons, Ltd.

In this paper, we propose a method to achieve effective facial emotional expressivity for embodied conversational agents by considering two types of asymmetry when exploiting the Valence-Arousal-Dominance representation of emotions. Indeed, the asymmetry of facial expressions helps to convey complex emotional feelings such as conflicting and/or hidden emotions due to social conventions. To achieve such a higher degree of facial expression in a generic way, we propose a new model for mapping the Valence-Arousal-Dominance emotion model onto a set of twelve scalar Facial Part Actions (FPA)s built mostly by combining pairs of antagonist Action Units (AU) from the Facial Action Coding System (FACS). The proposed linear model can automatically drive a large number of autonomous virtual humans or support the interactive design of complex facial expressions over time. By design our approach produces symmetric facial expressions, as expected for most of the emotional spectrum. However more complex ambivalent feelings can be produced when differing emotions are applied on the left and right sides of the face. We conducted an experiment on static images produced by our approach to compare the expressive power of symmetric and asymmetric facial expressions for a set of eight basic and complex emotions. Results confirm both the pertinence of our general mapping for expressing basic emotions and the significant improvement brought by asymmetry for expressing ambivalent feelings

An analytical model describing the flexural response of vertically spanning out-of-plane loaded unreinforced masonry walls is presented in this paper. The model is based on the second-order Euler-Bernoulli beam theory and captures important characteristics of the out-of-plane response of masonry walls that have been observed in experimental tests and from numerical studies but for which an analytical solution was still lacking: the onset and the evolution of cracking, the peak strength of the out-of-plane loaded walls, and the softening of the response due to P−Δ effects. The model is validated against experimental results, and the comparison shows that the model captures both the prepeak and postpeak response of the walls. From the analytical model of the force-displacement curve, a formula for the maximum out-of-plane strength of the walls is derived, which can be directly applied in engineering practice.