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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.

Purpose. The purpose of this study is to consider the class of Morse – Smale flows on surfaces, to characterize its subclass consisting of flows with a finite number of moduli of stability, and to obtain a topological classification of such flows up to topological conjugacy, that is, to find an invariant that shows that there exists a homeomorphism that transfers the trajectories of one flow to the trajectories of another while preserving the direction of movement and the time of movement along the trajectories; for the obtained invariant, to construct a polynomial algorithm for recognizing its isomorphism and to construct the realisation of the invariant by a standard flow on the surface. Methods. Methods for finding moduli of topological conjugacy go back to the classical works of J. Palis, W. di Melo and use smooth flow lianerization in a neighborhood of equilibrium states and limit cycles. For the classification of flows, the traditional methods of dividing the phase surface into regions with the same behavior of trajectories are used, which are a modification of the methods of A. A. Andronov, E. A. Leontovich, and A. G. Mayer. Results. It is shown that a Morse – Smale flow on a surface has a finite number of moduli if and only if it does not have a trajectory going from one limit cycle to another. For a subclass of Morse – Smale flows with a finite number of moduli, a classification is done up to topological conjugacy by means of an equipped graph. Conclusion. The criterion for the finiteness of the number of moduli of Morse – Smale flows on surfaces is obtained. A topological invariant is constructed that describes the topological conjugacy class of a Morse – Smale flow on a surface with a finite number of modules, that is, without trajectories going from one limit cycle to another.&nbsp

PURPOSE: To improve the estimation of coil sensitivity functions from limited auto calibration signals (ACS) in SENSE-based reconstruction for brain imaging. METHODS: We propose to use deep learning to estimate coil sensitivity functions by leveraging information from previous scans obtained using the same RF receiver system. Specifically, deep convolutional neural networks (CNNs) were designed to learn an end-to-end mapping from the initial sensitivity to the high resolution counterpart; Sensitivity alignment was further proposed to reduce the geometric variation caused by different subject positions and imaging FOVs. Cross-validation with a small set of datasets was performed to validate the learned neural network. Iterative SENSE reconstruction was adopted to evaluate the utility of the sensitivity functions from the proposed and conventional methods. RESULTS: The proposed method produced improved sensitivity estimates and SENSE reconstructions compared to the conventional methods in terms of aliasing and noise suppression with very limited ACS data. Cross-validation with a small set of data demonstrated the feasibility of learning coil sensitivity functions for brain imaging. The network learned on the spoiled GRE data can be applied to predicting sensitivity functions for spin-echo and MPRAGE datasets. CONCLUSION: A deep learning based method has been proposed for improving the estimation of coil sensitivity functions. Experimental results have demonstrated the feasibility and potential of the proposed method for improving SENSE-based reconstructions especially when the ACS data are limited.

We construct examples of nonlinear maps on function spaces which are continuously differentiable in the sense of Michal and Bastiani but not in the sense of Frechet. The search for such examples is motivated by studies of delay differential equations with the delay variable and not necessarily bounded.

Determining the precise nature of the connection between preference, choice, and welfare has arguably been the central project in the field of welfare economics, which aims to offer a proper guide for economists in the making of policy decisions that affect people’s welfare. The two leading approaches here historically – the revealed preference and latent preference approaches – seem equally incapable of so guiding economists. I argue that the deadlock here is due to welfare economists’ failure to recognize a crucial distinction between two senses of “preference.” I analyze and defend these senses of “preference,” and argue that each shares a close connection with just one of choice and welfare. This analysis reveals how economists should conceive of both the connections between “preference,” choice, and welfare, and the proper roles of these concepts in welfare economics. I conclude by showing this analysis to best explain the plausibility of two leading alternative approaches from Hausman and Sugden.

In recent years, growing awareness of global environmental conservation has increased the demand for power leveling through inter‐grid connections between nations or islands, and the introduction of renewable energy raises more necessity of energy leveling and remote connections between power‐generation facilities and power demand area. There is a lot of market interest in high‐voltage direct current (HVDC) technology, which is advantageous for long‐distance power transmission. HVDC power cables are playing an important role in this to connect HVDC‐generation facilities and the existing power network efficiently. Solid insulation power cables, in particular, are attracting attention worldwide and various insulation materials have been proposed. Though cross‐linked polyethylene (XLPE) cable is widely used for alternative current (AC) transmission, if attempts are made to adapt AC‐XLPE cables for DC transmission as significant electric field enhancement by space‐charge accumulation may occur, then breakdown would take place especially during surge voltage in opposite polarity and polarity reversal. Therefore, it is desired to innovate a special insulating material for DC transmission to suppress the accumulation of space charge.In this chapter about such insulating material for DC transmission cable, nanocomposite that is composed from polymer materials as a matrix and nanofiller, polymer blend, and copolymer as kinds of composites in a broad sense are described. And for the real production of the nanocomposite materials in the near future, to increase the performance and reliability of the production and a deeper understanding of insulation and dielectric phenomena, some issues and perspectives are shown.

This article presents a readout integrated circuit (ROIC) for capacitive touch-screen panels (TSPs) employing an amplitude-modulated multiple-frequency excitation (AM-MFE) technique. To prevent charge overflow, which occurs periodically at the beat frequency of the excitation frequencies, the ROIC modulates the amplitude of the excitation voltages at a mixing frequency derived from the excitation frequencies. Thus, the ROIC can sense the charge signal without charge overflow and maximize the signal-to-noise ratio (SNR) by increasing the amplitude of the excitation voltages up to the sensing range of the readout circuit. The proposed ROIC was fabricated in a 0.13- $\mu \text{m}$ standard CMOS process and was measured with a 32-in 104 $\times $ 64 touch-screen panel using 1 and 10 mm metal pillars. It reduces charge overflow up to 33.9 dB compared to operation without AM-MFE. In addition, the ROIC achieves a frame rate of 2.93 kHz, and SNRs of 41.7 and 61.6 dB with 1 and 10 mm metal pillars, respectively.

Multi-axis integration is important for micro-electromechanical system(MEMS) gyroscopes in the future. In this paper, a monolithic integrated tri-axis gyroscope and interface circuit are designed and implemented. The presented tri-axis gyroscope with single drive and multi sense axes is fully decoupled in structure among the drive and sense modes. Quadrature coupling can also be further reduced by the in-plane and out-of-plane correction electrodes. The pitch(roll) structure is designed as a unilateral unequal height comb, which reduces the damping and improves the Q value of pitch and roll modes and simplifies the fabrication process. In addition, the interface circuit adopts a closed-loop drive and open-loop sense circuit, an additional decoupling module that effectively reduces the cross axis sensitivity. Finally, a gyroscope prototype was tested to evaluate its performance. The designed tri-axis gyroscope has low bias instability(1.2821°/h) and good noise performance(0.1635°/ $\surd \text{h}$ ). The coupling coefficient is even below 1% after adding decoupling modules. Meanwhile, the bandwidth can meet the needs of the gyroscope working in a low-frequency environment.

Microbial fuel cells (MFCs) are recognized as an efficient method to utilize biomass to generate power while simultaneously treats wastewater. Micro-electro-mechanical system (MEMS) technology enables miniaturization of the MFCs system. Miniaturized MFCs through MEMS strengthen the system’s reaction capacity that makes it suitable for environmental sense field applications such as sensors or biomedical actuators. In this work, MEMS technology is employed to deposit metal layers on the surface of the anode/cathode electrode to enhance the power density of the MFC. Hence, micromixers and micro-pillars in the anode tank along with the influence of the electron transport media on MFC performance were evaluated. The introduction of the micro-mixers promotes the full mixing of the anolyte. The inclusion of the micro-pillars increases the surface area of the electrode, thereby enhancing the electrical energy output of the MFC. Results revealed that the introduction of the microstructure and the electron transfer media to the anolyte in the MFC have yielded a maximum current of 66.55 μ A cm−2, a maximum power density of 3.28 μ W cm−2, and an internal resistance value of 2 . 57 k Ω . Moreover, the inclusion of several micro-mixers and micro-pillar structures to the anode tank has shown the performance enhancement of MFC. Relevant research results will provide a reference for future research on the combination of MFCs and sensors.

This paper presents a multi-threshold inertial switch demonstrated experimentally and through simulation. A laterally-driven multi-threshold inertial switch based on SOIMUMPs has been fabricated. The device has been tested by a drop-table test system under different shock accelerations with various amplitudes and pulse widths. In addition to experimental data, finite element simulation has been used to further assess the device’s performance. The designed switch is a 2-axis device capable of triggering in all directions in a single plane. This work demonstrates that the designed inertial switch with 3 threshold levels can perform quantitative acceleration measurements while saving power when not activated. The multi-threshold inertial switch can sense a shock range of 800g–2600g. The same device principle can be extended for a higher number of bits. The axial disturbance performance shows that the inertial switch has high single-axial sensitivity and low axial cross-talk.

Numerous missions are being proposed which involve multiple spacecraft operating in close proximity in harsh charging environments. In such missions, the ability to sense the electrostatic potentia...

Some necessary and sufficient conditions are obtained that guarantee the oscillation of all solutions of two types of neutral integro-differential equations of third order. The integral is used in the sense of Riemann-Stieltjes. Some examples were included to illustrate the obtained results

The (Euclidean) hull of a linear code is defined to be the intersection of the code and its Euclidean dual. It is clear that the hulls are self-orthogonal codes, which are an important type of linear codes due to their wide applications in communication and cryptography. Let $$\mathbb F_q$$ be the finite field of order q and $$n = \frac{q^m-1}{q-1}$$ , where q is a power of a prime and $$m \ge 2$$ is an integer. Let $${\mathcal {C}}_{(q,n,\delta )}$$ be a projective narrow-sense BCH code over $$\mathbb F_q$$ with designed distance $$\delta $$ . In this paper, we will investigate both the dimensions and the minimum distances of $$\text {Hull}({\mathcal {C}}_{(q,n,\delta )})$$ , where $$2 \le \delta \le \frac{2(q^{\frac{m+1}{2}} -1)}{q-1}$$ if $$m \ge 5$$ is odd and $$2 \le \delta \le \frac{q^{\frac{m}{2}+1}-1}{q-1}-q+1$$ if $$m \ge 6$$ is even. As a byproduct, a sufficient and necessary condition on the Euclidean dual-containing BCH code $${\mathcal {C}}_{(q,n,\delta )}$$ is documented. In addition, we present some characterizations of the hulls of ternary projective narrow-sense BCH codes when $$\dim \Big (\text {Hull} ({\mathcal {C}}_{(3,n,\delta )})\Big )=k-1, \ k-2$$ for even $$m \ge 2$$ ; and $$\dim \Big (\text {Hull} ({\mathcal {C}}_{(3,n,\delta )})\Big )=k-1, \ k-2m-1$$ for odd $$m\ge 3$$ , where k is the dimension of $${\mathcal {C}}_{(3,n,\delta )}$$ .

This is the second of two articles about cases in which awards of “mesne profits” have been made against defendants who have occupied claimants’ land. The first article argues that the facts of cases where such awards have been made variously support claims in tort, contract or unjust enrichment and that practical consequences can flow from categorising the cases in one way or another. One is that different rules affect the assessment of remedies awarded to claimants depending on the claim that was made and the remedy that was awarded. The present article develops this point by examining the assessment principles governing “mesne profits” awards, according to whether these are classified as compensatory damages in tort, restitutionary damages in tort, orders that a defendant perform a contractual duty to pay a debt, compensatory damages for breach of contract, or orders that a defendant make restitution of an unjust enrichment.

Paper-based fluorescence devices, with smartphone aids, bring considerable operation convenience for tetracycline (TC) sensing. Nevertheless, they must meet the challenge in real determination against complicated backgrounds. Considering that, we present a programmable-printing paper-based device and then apply it to TC determination for various natural samples. MoS2 NPs and Gmp/Eu-Cit are synthetized as composite probes. A static quenching process is found with MoS2 NP fluorescence at 430 nm, while significant magnification of Gmp/Eu-Cit emission is obtained at 617 nm, establishing a valuable ratiometric indicator. Remarkably, two-stage programmable printing maximizes the proposed sensing capability. A transitive device, containing a gradually changing amount of a certain probe, is prepared to sense TC. With a homemade smartphone application and 3D-printed measurement chamber, the corresponding signals are examined to explore optimal setups. These setups are automatically processed to prepare the final-version device, not requiring manual operations. Benefitting from this interesting feature, the proposed device gains many rewards in performances. It effectively senses TC in a wide range from 12.7 nM to 80 μM and simultaneously provides naked eye-legible signals and smartphone-based readouts with confident selectivity and stability. This device is consequently applied for various samples of soil, river water, milk, and serum and meets well with HPLC-MS and recovery tests.

Interpersonal communication is so important in everyday life that it is desirable everyone who participates in the conversation is satisfied. However, every participant of the conversation cannot be satisfied in such cases as those wherein only one person cannot keep up with the conversation and feels alienated, or wherein someone cannot communicate non-verbal expressions with his/her conversation partner adequately. In this study, we have focused on facial direction and gaze among the various factors that are said to affect conversational satisfaction. We have attempted to lessen any sense of non-participation in the conversation and increase the conversational satisfaction of the non-participant in a tripartite conversation by modulating the visual information in such a way that the remaining two parties turn toward the non-participating party. In the experiments we have conducted in VR environments, we have reproduced a conversation of two male adults recorded in actual environments using two avatars. The experimental subjects have watched this over their HMDs. The experiments have found that visually modulating the avatars’ faces and gazes such that they appear to turn toward the subjects has increased the subjects’ sense of participation in the conversation. Nevertheless, the experiments have not increased the subjects’ conversational enjoyment, a component of the factors for conversational satisfaction.

The main goal of information retrieval is getting the most relevant documents to a user’s query. So, a search engine must not only understand the meaning of each keyword in the query but also their relative senses in the context of the query. Discovering the query meaning is a comprehensive and evolutionary process; the precise meaning of the query is established as developing the association between concepts. The meaning determination process is modeled by a dynamic system operating in the semantic space of WordNet. To capture the meaning of a user query, the original query is reformulating into candidate queries by combining the concepts and their synonyms. A semantic score characterizing the overall meaning of such queries is calculated, the one with the highest score was used to perform the search. The results confirm that the proposed "Query Sense Discovery" approach provides a significant improvement in several performance measures.

This paper proposes a variable mode control (VMC) for the power mismatch among inverters in autonomous microgrid. With this method, power mismatch, usually difficult to sense in traditional droop control, can be tackled easily by varying the control mode of inverters synchronously in a wireless manner without central controller. In order to synchronously vary the control mode in a wireless manner, this paper first analyses the phase relationship between inverter output voltage and power point coupling voltage to demonstrate the feasibility of adopting inverter output voltage as the quasi-synchronous signal for mode varying. This results in the wireless VMC of fundamental frequency, which greatly reduces the control complexity by removing the central control signals. Based on this strategy, this paper shows that many typical methods for power sharing, such as virtual impedance, voltage compensation, variable droop coefficient and coupling control, can be used for accurate power sharing in a VMC manner without central controller. Moreover, the VMC is based on the output voltage regulation rather than impedance match principle. Furthermore, power fluctuations and small signal models are analysed for parameter selection. Finally, simulations using MATLAB/Simulink and experiments are carried out to evaluate the performance of the proposed method.

It is an interesting problem to determine the parameters of BCH codes, due to their wide applications. In this paper, we determine the dimension and the Bose distance of five families of the narrow-sense primitive BCH codes with the following designed distances: Moreover, we obtain the exact parameters of two subfamilies of BCH codes with designed distances $$\bar{\delta }= b\frac{q^m-1}{q^2-1}$$ and $$\delta _{(a,t)}= (at+1)\frac{q^m-1}{t(q-1)}$$ with even m, $$1\le a \le \big \lfloor \frac{q-2}{t}\big \rfloor $$ , $$1\le b\le q-1$$ , $$t>1$$ and $$t|(q+1)$$ . Note that we get the narrow-sense primitive BCH codes with flexible designed distance as to a, b, c, t. Finally, we obtain a lot of the optimal or the best narrow-sense primitive BCH codes.