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In this paper, we study excess demand equilibrium problems in Euclidean spaces. Applying the Glicksberg's fixed point theorem, sufficient conditions for the existence of solutions for the reference problems are established. We introduce a concept of well-posedness, say Levitin–Polyak well-posedness in the sense of Painleve–Kuratowski, and investigate sufficient conditions for such kind of well-posedness.

Conventional digital LLC Synchronous Rectifier (SR) control typically uses detection circuits to sense the drain-source voltage of SR MOSFET in low output voltage applications, or gives SR duty cycle only considering the switching frequency in the microcontroller. They are difficult to be applied to the applications of 700 V high voltage and 6.6 kW high power directly due to the high dv/dt and large SR duty cycle variations, which poses serious challenge for SRs control. A bidirectional impedance-based SR driving scheme is presented for high voltage SiC LLC converter. Based on the LLC equivalent impedance, mathematical models are built to calculate the SR on-time in the forward and reverse modes, which can be tuned timely when the switching frequency and load vary. Thus, both bidirectional LLC performance with high efficiency and high immunity to the switching noise can be achieved without adding auxiliary circuits. A prototype of 300-kHz 6.6-kW SiC bidirectional LLC charger was built. Compared to the conventional SR method, the LLC efficiencies improve 0.3% in the forward and reverse modes at full load by using the proposed SR driving scheme.

High temporal-spatial resolution measurement of the air temperature is important for human health and research on the urban heat island. Since conventional methods can hardly meet the demands, a novel measurement of the air temperature has been proposed by using the battery temperature sensor of the smartphone, which can provide a refined data in a crowdsourcing way. Firstly, a heat transfer retrieval model among the air temperature, battery temperature, and the pocket of the clothing or the desk is established. Then coefficients of the retrieval model are obtained by the dataset measured through the smartphone and the thermometer in the linear fitting method. Finally, we retrieve the air temperature in a specific site with time resolution of one minute based on the retrieval model by three independent smartphones. Retrieval air temperature of four models strongly correlates to the true value, indicating that the retrieval model can sense the variation of the air temperature. Meanwhile, root mean square errors of the 1st and 4th model are 0.35 and 0.45∘, implying the high retrieval accuracy. The results suggest that the retrieval model can provide a short timescale (minute) and robust estimation of the air temperature by smartphone temperature sensors.

In this work, a reverse saliency (RS) spoke-type permanent magnet (PM) synchronous motor (PMSM) besides its hybrid adaptive notch filter (HANF) based self-sensing for driving a solar photovoltaic water pump system (WPS) is presented. The conventional spoke-PMSM driven WPS experiences two types of problems. Firstly, the motor is operated with a flux-weakening current to produce positive reluctance torque, thereby increasing the PM demagnetization risk. Secondly, an encoder is used to sense the rotor angle, which in turn affects the cost and reliability. To solve the first problem, the RS-PMSM is presented, which operates with a flux-intensifying current to produce positive reluctance torque. While second issue is resolved by using the HANF based rotor angle estimation. Although conventional methods give an estimate of rotor angle, they do not eliminate both the DC-offset and dominant harmonics. The superiority of both the RS-PMSM and HANF over existing solutions, is shown respectively by using finite-element methods and MATLAB/ Simulink based performances. Besides, a prototype motor is also manufactured. The performance of RS-PMSM prototype along with its HANF based self-sensing is obtained in the laboratory and various test results are reported. Meanwhile, a comparison of the HANF with available self-sensing techniques, is also performed.

In this paper, we study the phenomenon of concentration and the formation of delta shock wave in vanishing adiabatic exponent limit of Riemann solutions to the Aw–Rascle traffic model. It is proved that as the adiabatic exponent vanishes, the limit of solutions tends to a special delta-shock rather than the classical one to the zero pressure gas dynamics. In order to further study this problem, we consider a perturbed Aw–Rascle model and proceed to investigate the limits of solutions. We rigorously proved that, as the adiabatic exponent tends to one, any Riemann solution containing two shock waves tends to a delta-shock to the zero pressure gas dynamics in the distribution sense. Moreover, some representative numerical simulations are exhibited to confirm the theoretical analysis.

Motivated in part by a problem in simulated tempering (a form of Markov chain Monte Carlo) we seek to minimise, in a suitable sense, the time it takes a (regular) diffusion with instantaneous reflection at 0 and 1 to travel from the origin to 1 and then return (the so-called commute time from 0 to 1). We consider the static and dynamic versions of this problem where the control mechanism is related to the diffusion’s drift via the corresponding scale function. In the static version the diffusion’s drift can be chosen at each point in [0,1], whereas in the dynamic version we are only able to choose the drift at each point at the time of first visiting that point. The dynamic version leads to a novel type of stochastic control problem.

This paper is concerned with an expansive errors-based fuzzy adaptive prescribed performance control of a class of MIMO nonlinear systems in the presence of unknown interconnection nonlinearities using fuzzy residual approximation technique. Based on an newly defined expansive error, residual nonlinearities' fuzzy approximation scheme is proposed. The merits of designed control can be presented as twofold: \textit{i)}, by incorporating an expansive errors-based technique into pioneering prescribed performance control methodology, the defined intermediate and output tracking errors are kept within the regions represented by preassigned functions and control parameters simultaneously, and \textit{ii)}, expansive errors-related residual nonlinearity is approximated by fuzzy logic systems, which further ameliorates the output tracking performance by compensating the affects raised by composite inner and interconnection nonlinearities among subsystems. With the designed expansive errors-based fuzzy adaptive prescribed performance control, all the closed-loop signals are kept bounded in the sense of Lyapunov stability theorem. Comparative simulation studies are presented to verify the effectiveness and advantages of theoretical findings.

This article addresses the problem of stabilizing a continuous-time switched system affected by a completely unknown disturbance, data quantization, and time-varying delay. In the sense of combined dwell-time and average dwell-time, it is assumed that the switching is slow enough. Suppose that the bound of delay is known but the one of disturbance is unknown. An estimation for the bound of disturbance is used to counteract the unknown disturbance. By extending the approach of the delay-free case, a communication and control strategy is developed by introducing a virtual system. On this basis, the exponential decay and practical stability of the closed-loop system are guaranteed by using a Lyapunov function. Two examples are illustrated to show the usefulness of the proposed framework for stability analysis of some classes of switched systems.

In the literature, giant magnetoresistive (GMR) point field detectors (PFDs) were integrated in terminals of Si IGBT modules for galvanically isolated current sensing in machine drives. This work presents a PFD-based current sensing system that can be fully integrated in the direct bonded copper (DBC) region of SiC power modules. The physics of phase shift errors caused by the Nickel (Ni) plating in the SiC power module is investigated. To address current sensing phase errors, a real-time phase shift reduction method is proposed. A bandwidth extension method is proposed to meet the sensing requirement of SiC devices that can switch at tens of kilohertz. The phase shift reduction and bandwidth extension methods are experimentally combined to sense the currents in the SiC DBC regions. The proposed current sensing has high bandwidth, minimal phase errors and low position sensitivity. The sensed currents can be used for high performance control and protection of SiC module-based converters.

A static output feedback based event-triggered control mechanism for a class of switched nonlinear systems with a passivity property is proposed in this paper. Each subsystem of such a switched system does not necessarily have passivity in the classical sense, while maintaining the passivity property only on the active time intervals. Moreover, passivity is based on multiple storage functions and the storage functions are allowed to increase at switching instants. The proposed event-triggered output feedback controller can not only maintain asymptotic stability but also exclude Zeno behavior under some conditions. Finally, a numerical example is presented to illustrate the effectiveness of the method.

This article is concerned with the cooperative tracking control problem for heterogeneous multiagent systems in a leader-following form under a directed graph. The dynamics of each following agent is unknown, obeying a strict-feedback form. With the help of fuzzy-logic systems, input filters, and constraint-handling schemes, a fully distributed output-feedback control algorithm is proposed to achieve output synchronization with prescribed performance and guarantee boundedness of signals in the closed-loop systems. In addition, the algorithm exhibits a simplicity control attribute in the sense that: 1) the control design utilizes only relative output measurements, and no extra information needs to be transmitted via the network and 2) the issue of explosion of complexity is addressed, without employing command filters or dynamic surface control techniques. Finally, the simulation results clarify and verify the established theoretical findings.

A planar dual-band dual-sense circularly polarized (CP) microstrip array is proposed. This array is implemented on a single-layer substrate and easily extended to the design of a larger array. A new antenna element is exploited by symmetrically placing the non-radiative resonators on four side edges of a square patch. A quantitative design method is proposed based on the equivalent circuit model of the antenna element. For given two operating frequencies, the required design parameters of the patch and non-radiative resonators can be calculated. Theoretical magnitude ratio and phase difference responses of two far-field components, as well as axial ratio responses under different parameters, are presented to reveal the characteristics of the antenna element. Full-wave simulation results are found to agree well with the theoretical ones. To further validate the effectiveness, a 2×2-element dual-band dual-sense CP array operating at 2.40 and 2.68 GHz is designed, fabricated and measured, where a small frequency ratio of 1.117 is achieved. The measured realized gains in the low and high bands are 11.7 and 11.8 dBi, respectively, which are approximately equal.

Electronic skins are artificial skin-type multifunctional sensors, which hold great potentials in intelligent robotics, limb prostheses and human health monitoring. However, it is a great challenge to independently and accurately read various physical signals without power supplies. Here, a self-powered flexible temperature-pressure bimodal sensor based on high-performance thermoelectric films and porous microconed conductive elastic materials is presented. Through introducing flexible heat-sink design and harvesting body heat energy, the thin-film thermoelectric device could not only precisely sense temperature signal but also drive the pressure sensor for detecting external tactile stimulus. The integration of Bi-Te based thermoelectric film with high stability in wide temperature range enables the sensor to sense the ambient temperature with high resolution (

In this paper, a same-sense circularly polarized grid-slotted patch antenna with wide axial ratio bandwidth is proposed. The rectangular grid-slotted patch on top and bottom planes are excited through flipped Z-shaped slots pair using a stripline feed to generate same-sense circular polarization with wider axial ratio bandwidth. Characteristic mode analysis is used in the design of the antenna to analyze the desired orthogonal modes. Variations of the resonant frequencies, axial ratio bandwidths and local minimas with the design parameters are discussed. The antenna has a 3 dB axial ratio bandwidth of about 21% from 4.07 GHz to 5.02 GHz, with the realized gain ranging from 2 to 3.5 dBic.

Wireless power transfer (WPT) is emerging as the preeminent way to charge electric vehicles, but there appears to be no fair way to measure the power transfer. In this article, Faraday coil transfer-power measurement (FC-TPM) is presented. FC-TPM employs non-contact, open-circuited sense coils to measure the electromagnetic field from WPT and calculates the real power propagating through the air gap between the transmitter and receiver coils. What is measured is the real electromagnetic power, representing the pure dispensation of energy that unambiguously demarcates the losses on either side. FC-TPM was demonstrated to be 0.1% accurate in hardware over an Rx coil misalignment of up to 10 cm using a 1-kW WPT system. Fair metering incentivizes businesses and individuals to make choices that conserve energy and advance technology by providing more information and by properly assigning the financial loss. This article is accompanied by a video highlighting the essential contributions of this article.

For delayed singular switched positive systems(SSPSs) under mode-dependent minimum dwell time(MDMDT) switching signal, the stability and standard gain performance in the sense of L 1 -gain and L ∞ -gain are analyzed in this paper, and both continuous-time and discrete-time cases are taken into account. Firstly, a sufficient stability condition for delayed continuous-time SSPSs under MDMDT switching signal is provided, and meanwhile, to analyze the disturbance attenuation performance, the standard gain performance conditions in the sense of L 1 -gain and L ∞ -gain are proposed, respectively. Next, considering delayed discrete-time SSPSs under MDMDT switching signal, sufficient stability condition and standard gain performance conditions in the sense of L 1 -gain and L ∞ -gain are put forward, respectively. Moreover, for delayed SSPSs with minimum dwell time switching signal, stability and standard gain performance are also analyzed. At last, the validity of theoretical results are proven via two examples.

Abstract. The present research was aimed at providing a German version of the Personal Sense of Power Scale (GPSPS; Anderson et al., 2012 ) and testing its psychometric properties. A personal sense of power describes the perception of one’s ability to influence others. Probably every human relationship can be characterized by differences in power, which means that the measurement of experienced power is highly relevant. The availability of appropriate measures in different languages will help improve research and cross-cultural comparisons. Five studies were conducted. Internal consistency was high across all studies. Stability across 6 and 12 weeks was also high. A good fit was observed for a 6-item unidimensional version. Correlations with a variety of psychological and sociodemographic variables were in the expected directions, supporting nomological and criterion validity (Study 1). Measurement invariance across gender was demonstrated. In support of construct validity, a clinical sample scored significantly lower than others. Finally, two studies showed the sensitivity of a state version of the scale. We encourage researchers to use this scale as a reliable and valid instrument for assessing trait and state power.

In this paper, an optimal design for mid-range WPT system based on multiple repeaters is proposed, which aims at powering high voltage side sense module in HVDC applications. The mathematical model of the system is established. The characteristics of current distribution and impedance angle are analyzed under equally spaced situations. To further optimize the system, the optimized spaced structure with different distances is investigated, which can improve transferring efficiency under same distance requirement. The effect of load is also analyzed. A 1.5m prototype with 8 repeaters is built and the experimental results verify the feasibility of optimized coil arrangement, which can effectively improve efficiency, especially under light load situations.

In this paper, we are interested in obtaining an approximate numerical solution of the fractional heat equation where the fractional derivative is in Caputo sense. We also consider the heat equation with a heat source and heat loss. The fractional Laplace-Adomian decomposition method is applied to gain the approximate numerical solutions of these equations. We give the graphical representations of the solutions depending on the order of fractional derivatives. Maximum absolute error between the exact solutions and approximate solutions depending on the fractional-order are given. For the last thing, we draw a comparison between our results and found ones in the literature.

This communication deals with the design of discrete apertures for wireless power transfer (WPT) within the Fresnel region, and provides some design guidelines to enhance WPT efficiency. In fact, although the aperture excitations optimization problem given two specific continuous or discrete apertures has been already researched, the effect of antenna arrays design choices (such as the number of antenna elements or their spacings) on the WPT efficiency has not been investigated yet. In order to do that, WPT efficiency formulation has been theoretically analyzed to understand the different antenna parameters contributions to the power transmission efficiency (PTE). After that, the problem of the array excitation optimization in the sense of maximum PTE has been revisited including cases with or without perfect impedance matching. Finally, different array designs and relative achievable PTEs have been compared systematically, and it is shown that arrays with inter-element spacing in the order of 0.3λ-0.4λ (tightly coupled arrays) provide the largest PTE (also for oblique WPT cases) when the array excitation is calculated taking into account the impedance mismatching.

Because of their advanced properties inherited from their constituent atomic layers, van der Waals heterostructures such as graphene/MoS 2 are promising candidates for many optical and electronic applications. However, because heat tends to be generated during the operation of nanodevices, thermal expansion is an important phenomenon to consider for the thermal stability of such heterostructures. In the present work, molecular dynamics simulations are used to investigate the thermal expansion coefficient of the graphene/MoS 2 heterostructure, and how the unavoidable misfit strain affects that coefficient is revealed. The misfit strain can tune the thermal expansion coefficient by a factor of six, and this effect is quite robust in the sense that it is insensitive to the size or direction of the heterostructure. Further analysis shows that the misfit strain offers an efficient means of engineering thermally induced ripples, this being the key mechanism for how the misfit strain affects the thermal expansion coefficient. These findings provide valuable information about the thermal stability of van der Waals heterostructures and offer help for practical applications of nanodevices based on such heterostructures.

We have developed a Liouville partial-differential-equation (PDE)-based method for computing complex-valued eikonals in real phase space in the multivalued sense in attenuating media with frequency-independent qualify factors, where the new method computes the real and imaginary parts of the complex-valued eikonal in two steps by solving Liouville equations in real phase space. Because the earth is composed of attenuating materials, seismic waves usually attenuate so that seismic data processing calls for properly treating the resulting energy losses and phase distortions of wave propagation. In the regime of high-frequency asymptotics, the complex-valued eikonal is one essential ingredient for describing wave propagation in attenuating media because this unique quantity summarizes two wave properties into one function: Its real part describes the wave kinematics and its imaginary part captures the effects of phase dispersion and amplitude attenuation. Because some popular ordinary-differential-equation (ODE)-based ray-tracing methods for computing complex-valued eikonals in real space distribute the eikonal function irregularly in real space, we are motivated to develop PDE-based Eulerian methods for computing such complex-valued eikonals in real space on regular meshes. Therefore, we solved novel paraxial Liouville PDEs in real phase space so that we can compute the real and imaginary parts of the complex-valued eikonal in the multivalued sense on regular meshes. We call the resulting method the Liouville PDE method for complex-valued multivalued eikonals in attenuating media; moreover, this new method provides a unified framework for Eulerianizing several popular approximate real-space ray-tracing methods for complex-valued eikonals, such as viscoacoustic ray tracing, real viscoelastic ray tracing, and real elastic ray tracing. In addition, we also provide Liouville PDE formulations for computing multivalued ray amplitudes in a weakly viscoacoustic medium. Numerical examples, including a synthetic gas-cloud model, demonstrate that our methods yield highly accurate complex-valued eikonals in the multivalued sense.

Despite a growing interest in power in sensemaking, our understanding of how power is linked with language is still theoretically underdeveloped. To this end, we develop a critical discursive perspective on sensemaking comprised of a three-part theoretical framework that elucidates the discursive underpinnings of power in organisational sensemaking. We first explain how discursive practices are used to turn cues into meaning. We then conceptualize how power operates within three layers of discursive practices: discursive strategies, genres, and discourses. This leads us to explain how the resulting sense can be conceptualized as common sense, new sense, or non-sense. The main contribution of this paper is to help us understand how discursive practices underpin the operation of power in organisational sensemaking, thus adding a missing piece to sensemaking research. Our discursive analysis also advances understanding of the role of language in sensemaking more generally, has methodological implications for sensemaking research, and helps to move critical discourse studies forward in organisational contexts.

Developing generic and self-adaptive methods to alleviate the nonlinearity issues remain of high importance for various microwave photonic (MWP) systems. Here, we propose and experimentally demonstrate a new digital linearization strategy to meet the requirements above. The key to our proposal lies on revealing that the dominant third-order nonlinear distortions (ND3s) have a ~ phase deviation with respect to the fundamental signals in analog MWP systems (e.g., links, filters, mixers). By leveraging this peculiarity, the cost-function possessing a closed-form solution is achieved for the rapid self-adaptive acquirement of optimal linearization coefficients. The proposed digital approach is distinguished by the feature of fast self-adaptivity to various MWP systems with diverse input signals, with no need of prior parameters of system or signal, complex training, or iterative optimization processes. Experimental investigations regarding the applications of our proposal in several typical MWP systems involving transmission link, filter and mixer are carried out. Achieved experimental results validate the feasibility and extensive applicability of our linearization strategy, in the sense of effective ND3s suppression for different MWP systems. Furthermore, the proposed linearization approach towards the simultaneous suppression of the second and the third-order distortions (ND2s & ND3s) is evaluated, in a low-biasing Mach-Zehnder modulator based MWP link. The combination of self-adaptive ND2s & ND3s mitigations and low-biasing technique experimentally shows a viable solution for highly required high-performance MWP links, in terms of high RF gain, low noise figure, wide operating bandwidth and large dynamic range.

Organizations operating in extreme contexts regularly face dangerous incidents they can neither prevent nor easily control. In such circumstances, successful sensemaking can mean the difference between life and death. But what happens afterwards? Our study of emergency management practitioners following a major bushfire reveals a process of post-incident sensemaking during which practitioners continue to make sense of the incident after it ends, during the subsequent public inquiry, and as they try to implement the inquiry’s recommendations. Different varieties of sensemaking arise during this process as practitioners rely on different forms of coping to develop and share new understandings, which not only make sense of the original incident, but also enable changes to help the organization deal with future incidents. Our study also shows that practitioners experience a range of emotions during this process, some of which inhibit sensemaking while others – particularly different forms of anxiety – can facilitate it. Our study makes an important empirical contribution to recent theoretical work on varieties of sensemaking and provides new insights into the complex role of emotions in sensemaking in extreme contexts.

Low carbon economy, energy conservation and environmental protection is one of the important tasks of current and future economic and social development. The large-scale development and utilization of all kinds of clean energy has accelerated the speed of China’s energy transformation. Rail transit system is a large power consumer. In recent years, the transportation system has been facing the triangle contradiction of new energy, cost and environmental protection. Connecting photovoltaic power generation to rail transit power supply system has many advantages: (1) it can reduce the operation cost of transportation system; (2) it can reduce the use of traditional thermal power; (3) it can reduce carbon emissions and protect the environment; (4) it can also promote the application of new energy. It makes a lot of sense. However, due to the randomness and uncertainty of photovoltaic power generation, the direct access of photovoltaic power generation to rail transit power supply system will bring a certain impact on rail transit power supply system. In this paper, the LSTM neural network is used to predict the load of photovoltaic power generation, which effectively ensures the accuracy of prediction, and then improves the stability of photovoltaic power generation when connected to the rail transit power supply system.

In this study, the multi-step fractional differential transform method (MSFDTM) is employed to obtain approximate analytical solutions of stiff systems of fractional order. The fractional derivative is described in the Caputo sense. Several numerical experiments are carried out to illustrate the feasibility of MSFDTM as an approximate analytical solution technique for stiff systems of fractional order.

Bell, ZW, Spitz, RW, Wong, V, Yamada, Y, Song, JS, Abe, T, and Loenneke, JP. Can individuals be taught to sense the degree of vascular occlusion? A comparison of methods and implications for practical blood flow restriction. J Strength Cond Res 36(12): 3359-3365, 2022-The study objective was to determine whether subjects could be conditioned to a relative blood flow restriction pressure in the lower body and compare 2 separate conditioning methods (unconstrained vs. constrained). Thirty-five subjects completed 4 visits, involving measurements for arterial occlusion and pressure estimations at 5 minutes and 24 hours after conditioning. The constrained method involved applying 40% of measured arterial occlusion 11 times, along with 10% above and below this pressure. The unconstrained method was time-matched, involving a series of inflations to 40% arterial occlusion for 12 seconds and then deflated for 22 seconds. Data are presented as mean differences (95% credible interval) unless otherwise noted. The absolute error between conditioning methods was found to be similar at 5 minutes (-1.1 [-5.9, 3.7] mm Hg) and 24 hours (-2.4 [-7, 2.2] mm Hg) after conditioning. The constant error differed between methods at 5 minutes [-8.2 (-14.4, -1.9) mm Hg] but was similar at 24 hours (-2.5 [-8.5, 3.6] mm Hg; H0: 0.680; H1: 0.068; and H2: 0.252) after conditioning. The bias and 95% limits of agreement for the unconstrained method were -3.9 (-33.8, 25.9) mm Hg at 5 minutes and -2.9 (-32, 26.1) mm Hg at 24 hours. The agreement for the constrained method was 4.2 (-28, 36.5) mm Hg at 5 minutes and -0.54 (-37.3, 36.2) mm Hg at 24 hours. Conditioning methods produced similar levels of absolute error, indicating that either method may offer a viable means of pressure application. Most estimates were between 20 and 60% of arterial occlusion pressure. Additional conditioning sessions may be needed to narrow this range at the individual level.

The MAP approach provides a way to analyze the steady-state handling behavior of road/race cars. It is completely general, in the sense that is can be employed for any real car, and for any mathematical model as well. Two concepts play a central role in MAP: the achievable region, that is the totality of the achievable trim conditions for a given vehicle, and the level (handling) curves inside the achievable region, to highlight the vehicle peculiar features. The envelope of level curves is often a good practical way to obtain the achievable regions.

We improve entropy bounds for a self-timed ring based true random number generator, taking the timing of the reference clock signals into account. The models we discuss encompass both perfect and jittered reference clocks. Importantly, our novel analysis of jittered reference clocks can be used to study how robust the improved entropy bounds are. We use parity filters as post-processing blocks and improve results on the required minimal parity filter size to obtain a given target entropy. In addition, we see in numerical experiments that these models are robust in the sense that the minimal required size of a parity filter to exceed a given entropy bound does not change when weakening the assumption on the reference clock; i.e. when considering jittered instead of perfect reference clocks.

The present paper focuses on the use of the Multilevel Current Rectifier topology as an interconnection element between PV systems and the network or loads. In order to properly use the converter in connection with the PV system, several subjects such as the compatibility with the maximum power point tracking and the compatibility between the converter and the PV array must be taken into account. Compatibility between the converter and the PV array can be achieved by ensuring at least the maximum power point is a point that the converter can work with. In this sense, this work focuses on the operating conditions to guarantee the compatibility with the PV array. The main results are an analytical and experimental characterization of the operating range of the system using the Multilevel Current Rectifier. This operating range has a precision of 1 % . Leading to the conclution that not only the converter is a viable option, but also that the theory and methodology used can be extrapolated to another topologies.

This paper studies fixed-time stabilization (FxTS) of a general controllable linear system with an input delay τ. It is shown that such a problem is not solvable if the prescribed convergence time $T_{τ}$ is smaller than $2_{τ}$ . For $T_{τ} ≥ 3_{τ}$ , a solution based on linear periodic delayed feedback (PDF) without any distributed delay is established. For $T_{τ} > 2_{τ}$ , a solution based on linear predictor-based PDF containing a distributed delay is proposed. For both cases, the gains of the PDF can be chosen as continuous, continuously differentiable, and even smooth, in the sense of infinitely many times differentiable. If only an output signal is available for feedback, two classes of linear observers with periodic coefficients are designed so that their states converge to the current and future states of the system at a prescribed finite time, respectively. With the observed current and future states, FTS can also be achieved by using respectively the PDF and observer-based PDF. A linear periodic feedback (without delay) is also established to solve the FxTS problem of linear systems with both instantaneous and delayed controls, which cannot be stabilized by any constant instantaneous feedback in certain cases. Two numerical examples verify the effectiveness of the proposed approaches.

In this paper, a new methodology for the design of sampled--data dynamic output feedback stabilizers, by means of Lyapunov--Krasovskii functionals, for nonlinear systems with state--delays, is presented. The notion of Dynamic Output Steepest Descent Feedback (DOSDF), induced by a general class of Lyapunov-Krasovskii functionals, is introduced. Then it is shown that DOSDFs, no matter whether continuous or not, are stabilizers in the sampleandhold sense. The main advantage of the proposed methodology is that all kinds of discontinuities, in the function describing the DOSDF, are here accommodated. This fact greatly enlarges the possibilities of designing sampled--data dynamic output feedback stabilizers for nonlinear systems with state-delays. The inter-sampling system behavior as well as time-varying sampling intervals are taken into account. The stabilization in the sample-and-hold sense theory is used to prove the results. The proposed methodology is novel as well for the delay-free case, which is here dealt with as a special case.

We show that Somos' constant is universal in sense that is similar to the universality of the Khinchin constant. In addition we introduce generalized Somos' constants, which are universal in a similar sense.

This book examines the nexus between City Networks, multilevel governance andmigration policy. Examining several City Networks operating in the European Union and the United States of America’s multilevel political settings, it brings migration research into conversation with both policy studies and political science. One of the first comparative studies of City Networks and migration, the book argues that multilevel governance is the result of a contingent process of converging interests and views between leaders in network organisations and national governments, the latter continuing to play a key gatekeeping role on this topical issue even in the supranational EU system. MInMUS project, ‘Migration Policies in Multi-level Political Settings. City Networks in Europe and North America,’ funded by the EU Marie Curie Fellowship programme (Standard Fellowships, Grant Agreement No. 794012) -- 1. Introduction -- 2. Multilevel governance and city networks. Theorising the missing link.-- 3. City networks in multilevel policymaking on migration. A least-likely case for MLG? -- 4. Migration City Networks in the EU supra-national polity. Case-studies.-- 5. Migration City Networks in the US federal system. Case-studies.-- 6. City networks, migration and multilevel governance. Making sense of a (missing) nexus.

This chapter describes a qualitative study of how organizations use information to evaluate and hire graduating students into entry-level positions from one pre-professional undergraduate program. The study investigates how campus recruiters and hiring managers make sense of student job applicants' cognitive, non-cognitive, and technical abilities from data presented in résumés, academic transcripts, and through various interview techniques. The findings provide insight into the opportunities and challenges to incorporating alternative representations of learning—Comprehensive Learner Records—into the recruitment and hiring process. The findings also reveal how information about learning and learners is used to establish pipelines for recruiting and hiring recent college graduates. The study informs the design of future assessment and credentialing infrastructures, with the goal of expanding how “learning” is measured, defined, and represented in higher education to enhance diversity, equity, and opportunity for learners.

Differences in growth have been reported for tomato under LED compared to HPS light, however, it is not clear if breeding specific for LED supplemental light is worthwhile. Therefore, we derived four recombinant inbred line (RIL) tomato populations from parents with contrasting growth responses to different light spectra. These RIL populations were grown for four weeks under supplemental HPS or 95% red and 5% blue LED light in the greenhouse. For one population we also studied fruit production. Plant height and size of the side shoots of the young plants were strongly reduced under LED supplemental lighting compared to HPS in all populations. The adult plants showed shorter internode lengths, less trusses, less fruits, and lower yield of ripe fruits per plant under LED. However, when the unripe fruits at the last harvest day were included, the difference in yield between HPS and LED disappeared, indicating that the plants under LED light were compacter and slower in development, but in the end produced similar yield. We found numerous QTL, but hardly any of these QTL appeared to be significantly LED-specific. Also, we found very significant genetic effects of maternally inherited plastids and mitochondria, showing the importance of using a parental genotype as mother or as father. However, these effects were very similar between the two light conditions. We conclude that our study does not justify tomato breeding programs that are specifically targeted at 95% red and 5% blue LED supplemental lighting.

Ordinary computing machines prohibit self-reference because it leads to logical inconsistencies and undecidability. In contrast, the human mind can understand self-referential statements without necessitating physically impossible brain states. Why can the brain make sense of self-reference? Here, we address this question by defining the Strange Loop Model, which features causal feedback between two brain modules, and circumvents the paradoxes of self-reference and negation by unfolding the inconsistency in time. We also argue that the metastable dynamics of the brain inhibit and terminate unhalting inferences. Finally, we show that the representation of logical inconsistencies in the Strange Loop Model leads to causal incongruence between brain subsystems in Integrated Information Theory. PF is supported in part by funding from the Social Sciences and Humanities Research Council. RS thanks the Spanish Ministry of Economy and Competitiveness, grant PID2019-111680GB-I00, an AGAUR FI 2018 grant, and the Santa Fe Institute. GD acknowledges funding from the Austrian Science Fund (FWF) (START Prize Y-1261-N).

International audience

The quantized feedback stabilization problem is investigated for nonlinear hybrid stochastic time-delay systems with discrete-time observation in this article. A quantized discrete-time observation feedback controller is designed. The designed controller can make the stability and mean-square sense of the controlled system. Particularly, this note is the first to develop the stability criteria, which is not only related to the duration between two successive observations but also links to time lag of the system. By utilizing the Lyapunov method and inequality scaling techniques, the estimates for the duration and the time delay of the system are gained, respectively. Some case simulations are also provided to testify the proposed method and demonstrate its power.

The new benchmarks to determine the human skull precisely in 3D for the investigation of anatomic symmetry and asymmetry to verify the sagittal midline plane reference.

International audience; New investigations in the problems of polynomial stabilization are presented in this paper, where some relaxed results related to homogeneity theory leading to this polynomial stability with optimal decay rate are developed. To achieve our analysis, several physical examples are presented showing how we can construct stabilizing feedback laws making these closed loop systems polynomially stable with optimal decay rates. This allows the redesign of (a) homogeneous feedbacks stabilizing polynomially the Heisenberg system in weak sense, (b) and the polynomial observer for the angular momentum satellite with one control input.

Lyapunov approach plays a vital role in addressing the issue of stability in deterministic and random (stochastic) systems. This paper is involved in the study of stability of linear and nonlinear systems perturbed by a standard Brownian motion, random coefficients or coefficient functions acting as stochastic processes. We mainly focus on the stability in mean-square and stochastic stability of these systems. Some suitable Lyapunov functions imply the necessary conditions of mean-square stability and stability in probability. Stability of systems with random variable coefficients are firstly discussed in this paper. The theoretical findings are supported by some examples with stability regions and some numerical simulations.