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The power generation from renewable power sources is variable in nature, and may contain unacceptable fluctuations, which can be alleviated by using energy storage systems. However, the cost of batteries and their limited lifetime are serious disadvantages. To solve these problems, an improvement consisting in the collaborative association of batteries and supercapacitors has been studied. Nevertheless, these studies don't address in detail the case of residential and large-scale photovoltaic systems. In this paper, a selected combined topology and a new control scheme are proposed to control the power sharing between batteries and supercapacitors. Also, a method for sizing the energy storage system together with the hybrid distribution based on the photovoltaic power curves is introduced. This innovative contribution not only reduces the stress levels on the battery, and hence increases its life span, but also provides constant power injection to the grid during a defined time interval. The proposed scheme is validated through detailed simulation and experimental tests. [ABSTRACT FROM AUTHOR]

The hybrid force position control algorithm based on neural network is considered for a class of robot system with nonlinear uncertainties. Compared with previous work, not only the steady-state performance but also the transient-state performance is considered. Firstly, in order to relax the control design dependent on detailed system information, a fast hybrid position/virtual-force controller is presented to build a virtual-force field between the obstacles and robot. The virtual force is the control parameter, which is set to maintain an expected distance between obstacles and the robot with unknown nonlinear and parameter uncertainty. Secondly, in order to alleviate the computation burden of parameter learning, and enhance the dynamic mapping of network ability, the Elman neural network is introduced. The output signal come from hybrid position/virtual-force controller is fed back to Elman neural network. Furthermore, since uncertainties of robot dynamics and obstacle location information, Elman neural network is also used to compensate for uncertainties and improve system stability performance. The control design conditions are relaxed because of the developed dynamic compensator. Finally, both simulations and results of obstacle avoidance are performed to show the potential of the proposed methods. [ABSTRACT FROM AUTHOR]

This paper proposes a hybrid circuit between a conformal strongly-coupled magnetic resonance (CSCMR) and a strongly-coupled magnetic resonance (SCMR), for better wireless power transmission (WPT). This combination promises to enhance the flexibility of the proposed four-loop WPT system. The maximum efficiency at various distances is achieved by combining coupling-matching between the source and transmitting coils along with the coupling factor between the transmitting and receiving coils. Furthermore, the distance between transmitting and receiving coils is investigated along with the distance relationship between the source loop and transmission coil, in order to achieve the maximum efficiency of the proposed hybrid WPT system. The results indicate that the proposed approach can be effectively employed at distances comparatively smaller than the maximum distance without frequency matching. The achievable efficiency can be as high as 84% for the whole working range of the transmitter. In addition, the proposed hybrid system allows more spatial freedom compared to existing chargers. [ABSTRACT FROM AUTHOR]

Hybrid analog/digital precoding is a promising technique to reduce the hardware cost of radio-frequency components compared with the conventional full-digital precoding approach in millimeter-wave multiple-input multiple output systems. However, the large antenna dimensions of the hybrid precoder design makes it difficult to acquire an optimal full-digital precoder. Moreover, it also requires matrix inversion, which leads to high complexity in the hybrid precoder design. In this paper, we propose a low-complexity optimal full-digital precoder acquisition algorithm, named beamspace singular value decomposition (SVD) that saves power for the base station and user equipment. We exploit reduced-dimension beamspace channel state information (CSI) given by compressive sensing (CS) based channel estimators. Then, we propose a CS-assisted beamspace hybrid precoding (CS-BHP) algorithm that leverages CS-based CSI. Simulation results show that the proposed beamspace-SVD reduces complexity by 99.4% compared with an optimal full-digital precoder acquisition using full-dimension SVD. Furthermore, the proposed CS-BHP reduces the complexity of the state-of-the-art approach by 99.6% and has less than 5% performance loss compared with an optimal full-digital precoder. [ABSTRACT FROM PUBLISHER]

In this paper, ultrahigh-voltage (UHV) SiC devices with hybrid unipolar/bipolar operation are introduced and demonstrated. As the first step of such a device, a merged p-i-n Schottky (MPS) diode with an epitaxial p+-anode layer is proposed to reduce the conduction loss of a bipolar device in the low current region. A “snapback” phenomenon is intensively investigated by analytical modeling, device simulation, and experiment and a design guideline of snapback-free hybrid operating MPS diodes is presented. Using the design guideline, snapback-free MPS diodes are fabricated and forward characteristics are investigated. By using a proper edge termination structure, a UHV SiC MPS diode with breakdown voltage of 11.3 kV is demonstrated. [ABSTRACT FROM AUTHOR]

Electricity demand forecasting can provide the scientific basis for the country to formulate the power industry development strategy and the power-generating target, which further promotes the sustainable, healthy and rapid development of the national economy. In this paper, a new mathematical hybrid method is proposed to forecast electricity demand. In line with electricity demand feature, the framework of joint-forecasting model is established and divided into two procedures: firstly, the modified GM(1,1) model and the Logistic model are used to make single forecasting. Then, the induced ordered weighted harmonic averaging operator (IOWHA) is applied to combine these two single models and make joint-forecasting. Forecasting results demonstrate that this new hybrid model is superior to both single-forecasting approaches and traditional joint-forecasting methods, thus verifying the high prediction validity and accuracy of mentioned joint-forecasting model. Finally, detailed forecasting-outcomes on electricity demand of China in 2016-2020 are discussed and displayed a slow-growth smoothly over the next five years. [ABSTRACT FROM AUTHOR]

A mesh-structured N-doped graphene@Sb 2 Se 3 (NGS) hybrid was one-pot prepared to realize N-doping, nanostructuring and hybridization for a sodium-ion battery anode to deliver much larger reversible specific capacity, faster interfacial electron transfer rate, better ionic and electronic transport, higher rate performance and longer cycle life stability in comparison to the plain Sb 2 Se 3 one. The better performance is ascribed to the unique intertwined porous mash-like structure associated with a strong synergistic effect of N-doped graphene for dramatic improvement of electronic and ionic conductivity by the unique porous structure, the specific capacity of graphene from N doping and fast interfacial electron transfer rate by N-doping induced surface effect and the structure-shortening insertion/desertion pathway of Na + . The detail electrochemical process on the NGS electrode is proposed and analyzed in terms of the experimental results. [ABSTRACT FROM AUTHOR]

This paper presents a new family of hybrid Z-source boost dc–dc converters intended for photovoltaic applications, where the high step-up dc–dc converters are demanded to boost the low-source voltages to a predefined grid voltage. Because the boost capabilities of the traditional Z-source networks are limited, the proposed converters are composed of combine traditional Z-source networks in different ways to enhance the boost abilities of the traditional Z-source networks. The new version of the proposed Z-source converters is termed as hybrid Z-source boost dc–dc converters to satisfy the traditional benefits of Z-source networks with stronger voltage boost abilities which can also be applied to dc–ac, ac–ac, and ac–dc power conversions. The performances of the proposed converters are compared with other Z-source networks behaviors. The simulation and experimental results of the proposed converters are validated at different operating conditions. [ABSTRACT FROM PUBLISHER]

We design and realise a hybrid interferometer consisting of three paths based on integrated as well as on bulk optical components. This hybrid construction offers a good compromise between stability and footprint on one side and means of intervention on the other. As experimentally verified by the absence of higher-order interferences, amplitude and phase can be manipulated in all paths independently. In conjunction with single photons, the setup can, therefore, be applied for fundamental investigations on quantum mechanics. [ABSTRACT FROM AUTHOR]

Previous studies have mostly considered the competing risks to be independent even when the interpretation of the failure modes implies dependency. This paper studies the dependent competing risks model from Gompertz distribution under Type-I progressively hybrid censoring scheme. We derive the maximum likelihood estimations of the model parameters, and then the asymptotic likelihood theory and Bootstrap method are used to obtain the confidence intervals. The simulation results are provided to investigate the effects of different dependence structures on the estimations of parameters. Finally, one data set was used for illustrative purpose. [ABSTRACT FROM AUTHOR]

Cavity quantum electrodynamics allows one to study the interaction between light and matter at the most elementary level. The methods developed in this field have taught us how to probe and manipulate individual quantum systems like atoms and superconducting quantum bits with an exquisite accuracy. There is now a strong effort to extend further these methods to other quantum systems, and in particular hybrid quantum dot circuits. This could turn out to be instrumental for a noninvasive study of quantum dot circuits and a realization of scalable spin quantum bit architectures. It could also provide an interesting platform for quantum simulation of simple fermion–boson condensed matter systems. In this short review, we discuss the experimental state of the art for hybrid circuit quantum electrodynamics with quantum dots, and we present a simple theoretical modeling of experiments. [ABSTRACT FROM AUTHOR]

There is a rising interest in developing functional electronics using additively manufactured components. Considerations in materials selection and pathways to forming hybrid circuits and devices must demonstrate useful electronic function; must enable integration; and must complement the complex shape, low cost, high volume, and high functionality of structural but generally electronically passive additively manufactured components. This article reviews several emerging technologies being used in industry and research/development to provide integration advantages of fabricating multilayer hybrid circuits or devices. First, we review a maskless, noncontact, direct write (DW) technology that excels in the deposition of metallic colloid inks for electrical interconnects. Second, we review a complementary technology, aerosol deposition (AD), which excels in the deposition of metallic and ceramic powder as consolidated, thick conformal coatings and is additionally patternable through masking. Finally, we show examples of hybrid circuits/devices integrated beyond 2-D planes, using combinations of DW or AD processes and conventional, established processes. [ABSTRACT FROM AUTHOR]

This paper presents the design and experimental results of a Thomson coil-based fast mechanical switch for hybrid ac and dc circuit breakers rated at 30-kV voltage and 630-A current. The compact design with optimized circuit parameters and geometric dimensions of components targets 2-mm travel within 1 ms when driven by a 2-mF capacitor bank precharged to 500 V. The use and design of a disc spring as the damping and holding mechanism is presented. Structural design of a complete switch assembly rather than just the actuator is given. Experimental results show that the switch can travel 1.3 mm in the first 1 ms and 3.1 mm in the first 2 ms when driven by a 360-V 2-mF capacitor bank. Such fast mechanical switches facilitate hybrid circuit breaker interruptions within 2 or 3 ms for ultra-fast and highly efficient protections in 5–35 kV medium-voltage dc as well as ac systems. [ABSTRACT FROM PUBLISHER]

Developed hybrid integrated circuit with rated supply voltage of 1,4 V, current consumption 0,7 mA and overall dimensions 8×4×3 mm provides soft processing of the audio signal in analog microelectronic equipment. Given its konstruktorsko-technological and electrical parameters.

A hybrid-excited flux-switching (HEFS) machine was proposed by reducing the permanent-magnet (PM) length of an original flux-switching PM machine and introducing a set of field windings into the saved space. According to the PM locations, three typical topologies of HEFS machines emerged, namely, PM-Top, PM-Bottom, and PM-Middle, respectively. The preliminary analysis indicates that different configurations of magnets and field windings have significant influences on the electromagnetic performance of HEFS machines. Hence, this paper is focused on the flux-regulation theories and principles of the three topologies of HEFS machines employing two typical magnet materials, namely, ferrite, and NdFeB, respectively. It is found that the field winding in the PM-Top machine exhibits reversal flux-regulation functions to that in the PM-Bottom one. The weakest flux-regulation capability is found in the PM-Middle one, since this can be considered as a combination of PM-Top and PM-Bottom ones. Overall, the highest magnet utilization and a strongest flux-regulation capability are exhibited in the PM-Bottom HEFS machine. The theoretical analysis is validated by both 2-D finite-element analysis-based predictions and experimental measurements on three prototype HEFS machines. [ABSTRACT FROM PUBLISHER]

In this paper, a new energy control scheme is proposed for actively controlled hybrid dc microgrid to reduce the adverse impact of pulsed power loads. The proposed energy control is an adaptive current–voltage control (ACVC) scheme based on the moving average measurement technique and an adaptive proportional compensator. Unlike conventional energy control methods, the proposed ACVC approach has the advantage of controlling both the voltage and current of the system while keeping the output current of the power converter at a relatively constant value. For this study, a laboratory-scale hybrid dc microgrid is developed to evaluate the performance of the ACVC strategy and to compare its performance with other conventional energy control methods. Using experimental test results, it is shown that the proposed strategy highly improves the dynamic performance of the hybrid dc microgrid. Although the ACVC technique causes slightly more bus voltage variation, it effectively eliminates the high current and power pulsation of the power converters. The experimental test results for different pulse duty ratios demonstrated a significant improvement achieved by the developed ACVC scheme in enhancing the system efficiency, reducing the ac grid voltage drop and the frequency fluctuations. [ABSTRACT FROM PUBLISHER]

The current-induced perpendicular magnetic anisotropy magnetic tunnel junctions (p-MTJs) offer a number of advantages, such as high density and high speed. As p-MTJs downscale to $\sim 40$ nm, further performance enhancements can be realized thanks to high spin-torque efficiency, i.e., lower critical current density and higher thermal stability. In this paper, we investigate the origin of high spin-torque efficiency and give a phenomenological theory to describe the critical current reduction due to the subvolume activation. Based on various physical theories and structural parameters, a compact model of nanoscale MTJ is developed and demonstrates a satisfactory agreement with experimental results. Dynamic, static, and stochastic switching behaviors have been addressed and validated. Then, we perform mixed simulations for hybrid MTJ/CMOS read/write circuits, magnetic random access memory, and magnetic flip-flop to evaluate their performance. Analyses of energy consumption are given to show the prospect of MTJ technology node miniaturization. [ABSTRACT FROM AUTHOR]

In this study, a thin hybrid circuit-analog (CA) microwave absorbing double slab composite structure is presented. Unlike conventional CA absorbers, the composite spacer in the proposed structure is made up of a glass/epoxy and high permittivity layer of glass/epoxy-MWCNT composite, which contributes to the stable absorption performance in the curved surface while maintaining the thin thickness of the composite spacer. To design the microwave absorber, the genetic algorithm which is the most used evolutionary algorithm technique in this field was used. The total thickness of the designed double slab CA absorber was very thin thickness of 2.37 mm. Although the designed absorber has very thin thickness, it could satisfy the −10 dB absorption in whole X-band (8.2–12.4 GHz). The absorbing performance of the designed absorber was compared with other types of absorber. Also, to check the absorbing performance of the proposed structure in the curved surface, the echo radar cross section (RCS) was simulated in the X-band with other types of absorber. The simulated results proved an excellent performance of a proposed novel double slab CA absorber. [ABSTRACT FROM AUTHOR]

To open electromechanical switches within the range of tens of microseconds, we exploit repulsive electromagnetic forces between current-carrying conductor loops. For this we study the power conversion efficiency from electromagnetic to kinetic form. These studies suggest connecting moving coils in series rather than employing inductive coupling. These techniques are put into practice in two prototype switches: the first one is based on induction and the other on series connected coils. Measurements with a high-speed camera verify that both switches achieve accelerations in the magnitude of 140000 g and breaking distances of 1 mm within 50 \mus. The switch with series connected coils obtains 44% greater force than the one based on induction. [ABSTRACT FROM AUTHOR]

This work is aimed at facilitating the industrial adoption of agent technology. This paper proposes the hybrid agent architecture specific to the power system automation domain. The architecture builds on the logical-node concept of IEC 61850 and comprises a deliberative and a reactive layer, combining the advantages of both. By relying on the underlined industrial standards IEC 61850 and IEC 61499, the architecture ensures practical applicability and captures domain-specific concepts in the agent-based system design. The developed agent-based system was validated in the cosimulation framework. The architecture provides for rapid system development, reducing the software development life cycle. The benefits are in the traceability of the software requirements, reuse of software components, ease of redesign, and direct deployment of the system model. [ABSTRACT FROM PUBLISHER]

This paper presents simulation methodology that combines a local nonmatching grid with a discrete fracture model. Designed for 2D and 3D multiphase flow simulations in standard simulators, the method handles matrix-matrix, fracture-fracture, and matrix-fracture connections in the context of an unstructured, local nonmatching grid. The grid is generated at the fracture intersections, enabling accurate modeling of small control volumes between connecting fractures. Grids are obtained simply by redistributing the volume of small control volumes surrounding the small control volumes, making the method computationally efficient. A unified method to calculate the interblock transmissibility is used for both matching and nonmatching mesh. An unstructured finite-volume graph-based reservoir simulator with a two-point flux approximation reads the new grid by making a simple modification to the graph of connections between the control volumes. The method requires no special treatment of fracture-fracture or matrix-fracture transmissibility calculations and has the flexibility to simulate any flow problem efficiently. Several 2D and 3D numerical examples demonstrate the method's performance and accuracy. Both simple and complex fracture configurations are presented with various levels of geologic and fluid complexity. The numerical results are in good agreement with those of a reference solution obtained on a finely structured grid. [ABSTRACT FROM AUTHOR]

The operator-splitting schemes for integration of stiff diffusion–reaction systems were found to fail in error control, i.e. incurring O (1) relative errors, with splitting time steps larger than that required for fully explicit integration, when significant non-chemical radical sources are present. It was shown that, by excluding the transport term from the chemistry integration, errors by orders of magnitude may occur in radical concentrations solved in the chemistry sub-step, resulting in significant errors in the major species. The failing scenario is demonstrated with a toy problem and an unsteady perfectly-stirred reactor (PSR) for hydrogen/air with significant H radical concentration at inlet. A dynamic adaptive method for hybrid integration (AHI) of stiff chemistry is then proposed as a substitute for the operator-splitting schemes in such cases. The AHI method can obtain accurate solutions by integrating the fast species and reactions implicitly and the non-stiff terms, including slow reactions and non-chemical source terms, explicitly. Specifically, fast species and reactions are identified on-the-fly based on their analytically derived timescales, the rates of slow variables are evaluated explicitly and those of fast species are evaluated partial-implicitly. As such, the number of variables to be implicitly solved at each integration time step is reduced to the number of the fast species, resulting in a smaller Jacobian matrix and consequently lower computational cost compared with the fully implicit solvers. The hybrid method is validated in auto-ignition for hydrogen/air with different equivalence ratios and initial temperatures, and compared with the Strang splitting scheme for the toy problem and the unsteady PSR. Results show significant improvement in accuracy using the AHI method. [ABSTRACT FROM AUTHOR]

This paper presents a novel coupled line 180^\circ hybrid with non-interspersed input/output ports. With the combination of a weak coupling parallel coupled line and strong coupling trans-directional coupler, a non-interspersed input/output ports coupled line 180^\circ hybrid is obtained by using printed circuit board fabrication process, and reduced substrate area is achieved. The proposed hybrid owns the features of reducing the complexity of dc biasing for the next-stage active circuits. Moreover, it requires no bond wires, via-holes, or multilayer structures. The formula of the proposed hybrid is derived, and the characteristics of the hybrid are analyzed. Two prototypes are designed to verify the concept. One is arranged with the two couplers perpendicular to each other, and the other is constructed with the two couplers arranged in a line. The measured results are in good agreement with the simulated ones [ABSTRACT FROM AUTHOR]

A novel 180^\circ hybrid with two \lambda /4 sections of three-conductor coupled-line structure inhered different operating frequencies with overlapped characteristic and perfect isolation between the \Sigma -port and \Delta -port is employed to implement a Ka- to M-band single-balanced subharmonic mixer (SHM) in a 0.15-\mu\ m GaAs pHEMT process with a compact die size of less than 0.82\,\times\,0.83 \ mm^2. The thorough analysis based on the scattering matrix of the 180^\circ hybrid is also presented. Incorporating the inherent features of the 180^\circ hybrid with an antiparallel diode pair configuration, the proposed SHM achieved a wide operating bandwidth from 37 to 85 GHz with low conversion loss from 9 to 14 dB, enhanced local oscillation (LO)-to-RF isolation and 2LO-to-RF isolation under 10-dBm LO power level. This proposed architecture is really attractive to SHM design in modern millimeter-wave territory. [ABSTRACT FROM AUTHOR]

Large-scale chip-multiprocessors (CMPs) need a scalable communication structure characterized by low cost, low power, and high performance to meet their on-chip communication requirements. This paper presents a hybrid circuit-switched (HCS) network for on-chip communication in the large-scale CMPs. The HCS network, which is Advanced Microcontroller Bus Architecture (AMBA) compatible, is composed of bufferless switches, pipeline channels, and network interfaces. Furthermore, packets are transferred in a hybrid transmission scheme. If a message has only one packet, the transmission scheme for this message is packet switching. Conversely, if a message contains multiple packets, the transmission scheme for this message is circuit switching. We evaluate HCS networks with different channel depths and then compare the HCS network with the Stanford elastic buffer (EB) network. Our results show that the HCS network with two-depth channel requires 83% less power and occupies 32% less area compared with the EB network. Furthermore, under maximum frequency and single traffic, the HCS network with two-depth channel provides 37% lower zero-load latency, 390% higher maximum throughput per unit power, and 19% higher maximum throughput per unit area compared with the EB network. [ABSTRACT FROM AUTHOR]

Graphene/silicon CMOS hybrid integrated circuits (ICs) should provide powerful functions which combines the ultra-high carrier mobility of graphene and the sophisticated functions of silicon CMOS ICs. But it is difficult to integrate these two kinds of heterogeneous devices on a single chip. In this work a low temperature process is developed for integrating graphene devices onto silicon CMOS ICs for the first time, and a high performance graphene/CMOS hybrid Hall IC is demonstrated. Signal amplifying/process ICs are manufactured via commercial 0.18 um silicon CMOS technology, and graphene Hall elements (GHEs) are fabricated on top of the passivation layer of the CMOS chip via a low-temperature micro-fabrication process. The sensitivity of the GHE on CMOS chip is further improved by integrating the GHE with the CMOS amplifier on the Si chip. This work not only paves the way to fabricate graphene/Si CMOS Hall ICs with much higher performance than that of conventional Hall ICs, but also provides a general method for scalable integration of graphene devices with silicon CMOS ICs via a low-temperature process. [ABSTRACT FROM AUTHOR]

A recently published hybrid circuit model for folded-waveguide slow wave structures has been implemented in the 1-D large signal code CHRISTINE. The resulting code is applied to a design for a G-band (220 GHz) folded-waveguide traveling wave tube. Results of small and large signal gain are compared with those from TESLA, a 2-D code using the same circuit model. Conditions for accuracy of the 1-D model are illustrated and explained. The effects of an offset beam tunnel on circuit dispersion and amplifier stability are illustrated using the CHRISTINE code. [ABSTRACT FROM AUTHOR]

In order to study the ability of coupled neural oscillators to synchronize in the presence of intrinsic as opposed to synaptic noise, we constructed hybrid circuits consisting of one biological and one computational model neuron with reciprocal synaptic inhibition using the dynamic clamp. Uncoupled, both neurons fired periodic trains of action potentials. Most coupled circuits exhibited qualitative changes between one-to-one phase-locking with fairly constant phasic relationships and phase slipping with a constant progression in the phasic relationships across cycles. The phase resetting curve (PRC) and intrinsic periods were measured for both neurons, and used to construct a map of the firing intervals for both the coupled and externally forced (PRC measurement) conditions. For the coupled network, a stable fixed point of the map predicted phase locking, and its absence produced phase slipping. Repetitive application of the map was used to calibrate different noise models to simultaneously fit the noise level in the measurement of the PRC and the dynamics of the hybrid circuit experiments. Only a noise model that added history-dependent variability to the intrinsic period could fit both data sets with the same parameter values, as well as capture bifurcations in the fixed points of the map that cause switching between slipping and locking. We conclude that the biological neurons in our study have slowly-fluctuating stochastic dynamics that confer history dependence on the period. Theoretical results to date on the behavior of ensembles of noisy biological oscillators may require re-evaluation to account for transitions induced by slow noise dynamics. [ABSTRACT FROM AUTHOR]

This study presents a new design and implementation of a three-phase hybrid multilevel inverter (MLI) using space vector modulation. The proposed MLI consists of a reduced number of dc sources and switches to minimise the control complexity. The developed topology consists of two stages: main stage and auxiliary stage. The main stage is a conventional three-phase inverter with one high-voltage input dc source and six switches. The auxiliary stages contain three individual cells. Each cell consists of two switches and one low-voltage input dc source. This topology is a modular type and without changing the previous connection it can be extended for more number of output voltage levels by adding certain number of auxiliary stages. A space vector modulation control technique has been utilised in order to generate different switching sequences. The special feature of the proposed system is its capability to maximise the number of voltage levels using a reduced number of isolated dc voltage sources and electronic switches. A prototype has been developed and tested for various modulation indexes to verify the control technique and performance of the topology. Experimental results validate the simulation results and the experimental results show a good similarity with the simulation results. [ABSTRACT FROM AUTHOR]

An envelope-tracking hybrid field-circuit simulator is proposed for efficiently analyzing narrowband scattering from wire antennas loaded with nonlinear devices. The simulator models the interactions of fields with wires and lumped elements by coupling and simultaneously solving the thin-wire electric field integral equation and Kirchhoff's equations, respectively. The coupled nonlinear system of equations is iteratively solved by a time marching scheme that represents the fields, voltages, and currents of interest (signals) as a truncated series of harmonic sinusoids (carriers) multiplied with complex-valued time-varying coefficients (envelopes). Unlike time-domain simulators, which sample the signals at a rate proportional to their maximum frequency content, the proposed envelope-tracking simulator samples the envelopes at a rate proportional to their maximum bandwidth; thus, it requires significantly fewer time-steps when solving narrowband problems. Moreover, the envelope-tracking simulator is generally more accurate than its time-domain counterpart because of smaller integration and interpolation errors. Numerical results demonstrate that the proposed simulator improves the tradeoff between accuracy and computation time, especially when analyzing antennas excited by narrowband signals or loaded with weakly nonlinear devices. [ABSTRACT FROM AUTHOR]

A stacked printed circuit board (PCB) approach for prototyping 3-D microfabrication enabled millimeter and submillimeter wave components and subsystems is proposed. To demonstrate this approach, a 4 to 8 GHz two element tapered slot antenna array with integrated rectangular coaxial 90^\circ hybrid, and its stand-alone elements, are designed and fabricated. Measured subsystem results show properly formed radiation patterns, realized gain from 9 to 11 dBi, and 3-dB beamwidth from 30^\circ to 45^\circ. Excellent agreement between simulations and measurements of individual components and the full subsystem as well as outcomes of a tolerance study and comparison to a Ka band micromachined subsystem confirm suitability of the proposed approach for fast, low-cost prototyping of 3-D micromachined rectangular coaxial components and subsystems. [ABSTRACT FROM AUTHOR]

A recent advancement in VLSI that drastically improved the circuit density is the introduction of CMOL (CMOS/nanodevices hybrid), which consists of an overlay of a nanofabric over a CMOS stack. Combinational logic in CMOL is implemented from a netlist of NOR gates and Inverters by programming nanodevices placed between overlapping nanowires. The length of the nanowires is restricted, and therefore connectivity of the circuit elements is constrained to be within a certain radius, else additional buffers are required. In this paper we present a Tabu Search (TS) algorithm to address the assignment problem in CMOL. The heuristic is engineered to provide sub-optimal solution by efficient exploration of search space. Empirical results for ISCAS benchmarks are compared with previous solutions using GA, MA, and LRMA heuristics. Results show that in almost all cases, TS exhibits more intelligent search of the solutions subspace, and is able to find better solutions in less time. For all tested benchmarks, over 90 % reduction in average CPU processing time when compared with best published techniques was obtained. [ABSTRACT FROM AUTHOR]

This letter describes a very simple implementation of a digital pulse width modulator (DPWM) under 100 ps resolution in low-cost field-programmable gate arrays (FPGAs). The implementation is based on internal carry chains and logic resources which are present in most FPGA families. The proposed approach does not require manual routing or placement, consumes few hardware resources, and does not rely heavily on specialized phase-locked loop or clock management resources. A 50-MHz switching frequency DPWM with 60-ps resolution and a 1-MHz switching frequency DPWM with 90-ps resolution are experimentally demonstrated, with monotonicity and excellent linearity. [ABSTRACT FROM AUTHOR]

Electrical interconnects are becoming a bottleneck in the way towards meeting future performance requirements of integrated circuits. Moore's law, which observes the doubling of the number of transistors in integrated circuits every couple of years, can no longer be maintained due to reaching a physical barrier for scaling down the transistor's size lower than 5 nm. Heading towards multi-core and many-core chips, to mitigate such a barrier and maintain Moore's law in the future, is the solution being pursued today. However, such distributed nature requires a large interconnect network that is found to consume more than 80% of the microprocessor power. Optical interconnects represent one of the viable future alternatives that can resolve many of the challenges faced by electrical interconnects. However, reaching a maturity level in optical interconnects that would allow for the transition from electrical to optical interconnects for intra-chip and inter-chip communication is still facing several challenges. A review study is required to compare the recent developments in the optical interconnects with the performance requirements needed to reach the required maturity level for the transition to happen. This review paper dissects the optical interconnect system into its components and explains the foundational concepts behind the various passive and active components along with the performance metrics. The performance of different types of on-chip lasers, grating and edge couplers, modulators, and photodetectors are compared. The potential of a slot waveguide is investigated as a new foundation since it allows for guiding and confining light into low index regions of a few tens of nanometers in cross-section. Additionally, it can be tuned to optimize transmissions over 90° bends. Hence, high-density opto-electronic integrated circuits with optical interconnects reaching the dimensions of their electrical counterparts are becoming a possibility. The latest complete optical interconnect systems realized so far are reviewed as well. [ABSTRACT FROM AUTHOR]

Since each branch of the multiterminal DC circuit system relies on the DC circuit breaker for breaking and fault isolation, the prohibitive cost and huge volume of the Hybrid DC Circuit Breaker (HCB) limit its development and broad application in multiterminal flexible DC systems. Multiport hybrid DC circuit breaker (MP-HDCCB) based on device and branch sharing reduces the configuration cost of the circuit breaker to a certain extent. In order to further reduce the cost of MP-HDCCB, a novel MP-HDCCB topology based on hybrid switching devices is proposed, adopting full controlled switching devices to achieve rapidity of breaking fault current, and using semi-controlled switching devices in series to withstand the transient interruption voltage (TIV), so as to reduce the construction cost and technical difficulty. In this paper, the working principle and fault breaking strategy of the topology are introduced in detail, then the parameters of the major circuit are analyzed theoretically, and the parameter design of each branch is given. In the end, the rationality and validity of the proposed topology is tested and verified by simulations and experimental tests. [ABSTRACT FROM AUTHOR]

Compared with the traditional Rogowski coil, printed circuit board (PCB) Rogowski coil has the advantages of high measurement accuracy, simple manufacturing process and low cost. It has become an important device in current measurement. However, the existing PCB Rogowski coils are mostly closed, and the open-ended structure PCB Rogowski coils are susceptible to external magnetic field interference. This paper proposes an open-ended structure PCB Rogowski coil based on a new winding method, so that the two open-ended PCB Rogowski coils are evenly distributed when closed, while improving the coil's immunity to external magnetic fields based on the winding method of equal area of the de-wired and loop. In addition, this paper uses the hybrid integration circuit and the back-end matching method to achieve the broadband measurement performance of the sensor. Finally, the experimental results show that the mutual inductance difference between the closed and open-ended structure PCB Rogowski coil is less than 0.5% under the same wiring mode. Under the equivalent current interference at 50 mm from the measured current, the maximum interference coefficient of the open-ended structure coil is 1.45%; in sine sweep and pulse current test conditions, the frequency band is 34 Hz–3.5 MHz. [ABSTRACT FROM AUTHOR]

• The function failure phenomenon of the hybrid integrated quartz flexible accelerometer servo circuit caused by the corrosion and hydrolysis of the chip passivation layer is studied. • The failure of integrated circuits caused by the hydrolysis of polyimide has been studied. • The fault tree method is used to locate the failure of the quartz flexible accelerometer servo circuit. • Analyze the failure phenomenon using micro analysis and characterization methods. This paper studied the function failure of a quartz flexible accelerometer servo circuit manufactured by a thick-film hybrid integrated process. The circuit adopts the epoxy glue bonding process of the metal shell and the ceramic cover plate to encapsulate, and it is a non-airtight package. After the circuit is powered on, the quiescent current output is abnormal, and the DC voltage output is constant high potential, the acceleration detection function cannot be realized. In response to this phenomenon, the fault tree method is used to locate the failure location, and the fault is located at the abnormal function of the differential capacitor voltage converter chip. Using microscopic analysis and characterization methods, it can be seen that the hydrolysis and corrosion of the surface of differential capacitance-to-voltage converter chip causes leakage in the active area inside the chip, leads to the function failure of the circuit. The above research is of great significance to the design, storage and application of non-hermetic hybrid integrated circuits. [ABSTRACT FROM AUTHOR]

Hybrid quantum systems with inherently distinct degrees of freedom have a key role in many physical phenomena. Well-known examples include cavity quantum electrodynamics, trapped ions, and electrons and phonons in the solid state. In those systems, strong coupling makes the constituents lose their individual character and form dressed states, which represent a collective form of dynamics. As well as having fundamental importance, hybrid systems also have practical applications, notably in the emerging field of quantum information control. A promising approach is to combine long-lived atomic states with the accessible electrical degrees of freedom in superconducting cavities and quantum bits (qubits). Here we integrate circuit cavity quantum electrodynamics with phonons. Apart from coupling to a microwave cavity, our superconducting transmon qubit, consisting of tunnel junctions and a capacitor, interacts with a phonon mode in a micromechanical resonator, and thus acts like an atom coupled to two different cavities. We measure the phonon Stark shift, as well as the splitting of the qubit spectral line into motional sidebands, which feature transitions between the dressed electromechanical states. In the time domain, we observe coherent conversion of qubit excitation to phonons as sideband Rabi oscillations. This is a model system with potential for a quantum interface, which may allow for storage of quantum information in long-lived phonon states, coupling to optical photons or for investigations of strongly coupled quantum systems near the classical limit. [ABSTRACT FROM AUTHOR]

The goal of neuromorphic engineering is to build electronic systems that mimic the ability of the brain to perform fuzzy, fault-tolerant, and stochastic computation, without sacrificing either its space or power efficiency. In this paper, we determine the operating characteristics of novel nanoscale devices that could be used to fabricate such systems. We also compare the performance metrics of a million neuron learning system based on these nanoscale devices with an equivalent implementation that is entirely based on end-of-scaling digital CMOS technology and determine the technology targets to be satisfied by these new devices. We show that neuromorphic systems based on new nanoscale devices can potentially improve density and power consumption by at least a factor of 10, as compared with conventional CMOS implementations. [ABSTRACT FROM AUTHOR]

Hybrid circuit/packet networks where circuit and packet networks coexist are becoming attractive to support future Internet applications. They support both packet/ IP services and circuit/wavelength services. Packet services include traditional data services such as VPN, VoIP, and email, while dynamic circuit services include end-to-end bandwidth-intensive applications such as terascale science experiments. In present hybrid networks, such as ESnet, the bandwidth boundary between the circuit and packet sections of the network is fixed. However, a flexible boundary between the circuit and packet sections will enable cost-efficient bandwidth management in the network. Our study investigates two methods to dynamically migrate capacity between the circuit and packet sections, called vertical stacking and horizontal partitioning, and serves as a tutorial. In vertical stacking, the backup capacity of wavelength circuits can be dynamically exchanged between packet and wavelength services while ensuring survivability. The backup capacity can be used to protect wavelength services in the event of a failure and route packet traffic otherwise. In horizontal partitioning, the excess capacity on links in the packet section can be loaned to circuit services. We have conducted experiments using a snapshot of real traffic on ESnet with horizontal partitioning. Control mechanisms for our approaches that can be operational in ESnet are presented. [ABSTRACT FROM PUBLISHER]

The main aim of the work is the integration of two different fiber-optic sensors: the Michelson interferometric sensor, the Mach-Zehnder interferometric, the Sagnac interferometric and modalmetric sensors. The proposed hybrid sensor is a classical interferometer whose measuring arm is upgraded with modalmetric sensor. The theme of research is to assess the impact of modalmetric sensor to interferometer and comparative assessment of detection capabilities of interferometric sensor, modalmetric sensor and hybrid sensor for different types of excitations. The described tests concern the area of basic researches. The results can be used in the construction sensors with corresponding characteristics and properties to the appropriate applications. [ABSTRACT FROM AUTHOR]

Abstract: This paper presents a new hybrid steady-state modeling approach for air-conditioning systems. At the system level, it follows the first principles to keep the conservation of mass, energy, and momentum, respectively. At the component level, the physics-based component models are entirely or partially replaced with neural networks. Component neural networks can be trained using the data from laboratory or from the well-validated physics-based component models. Numerical comparisons between the system model consisting of component neural networks and that consisting of physics-based component models indicate that the two system modeling approaches give very close predictions in a wide range of operating conditions. With the proposed hybrid modeling approach, robustness and speed of system modeling can be significantly improved. [Copyright &y& Elsevier]

This paper presents the results of short-circuit tests with a 22.9 kV hybrid superconducting fault current limiter (SFCL) on the KEPCO test grid. The hybrid SFCL we used for the test had suffered from lots of field tests including a long term operation and it is still in working order. We have already proved that the SFCL showed high reliability as well as feasibility through a long term operation and short-circuit tests performed before. In this paper, we tried to study a dynamic characteristics of the same SFCL on the distribution power grid through short-circuit tests with a circuit breaker and a reclosing relay. An artificial fault generator (AFG) was used to generate fault currents in the KEPCO power test center. The two objectives of the tests are (1) verifying a precise reaction of the SFCL to reclosing operation and (2) a study for protection coordination with SFCL. The test results showed that the SFCL worked precisely with a fast recovery of the superconducting elements when we applied a one-time reclosing operation with the interval of 0.6 second. We also suggested a proper manipulation of the coordination of the protection system in distribution networks with the SFCL in the paper. [ABSTRACT FROM PUBLISHER]

Two identical Nb3Sn coils will be wound at the National High Magnetic Field Laboratory for different series-connected hybrid projects. A model coil with half the length of the production superconducting coil has been fabricated to qualify all fabrication steps. After winding each layer, the impedance spectrum test has been employed to detect short circuits. After impregnation the model coil will undergo a high-voltage surge test which will explore the margin of the layer insulation. Results of impedance testing are reported here. [ABSTRACT FROM PUBLISHER]

This paper describes the detailed design of the quench protection circuits (QPCs) for the superconducting toroidal field (TF) and poloidal field (PF) magnets of the satellite tokamak JT-60SA, which will be installed in Naka, Japan. The nominal currents to be interrupted and the maximum reapplied voltages are 25.7 kA and 2.8 kV for the TF QPCs and 20 kA and 5 kV for the PF QPCs. The innovative solution proposed in the QPC design is based on a hybrid circuit breaker (CB) composed of a mechanical bypass switch for conducting the continuous current, in parallel to a static CB for current interruption. The main choices of the final design are presented and discussed, either to confirm or to update and complete the study performed at the conceptual design level. [ABSTRACT FROM PUBLISHER]