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Electronic memory with ever-increasing storage capacity is always in high demand. Every year, a computer transforms into a smaller, faster, and more reliable device. Memristor is a passive aspect recently developed that is gaining popularity. The non-volatile and small area features of this element are very essential. A Memristor's ability to fabricate around CMOS architectures is a step forward in VLSI design enhancement. When developing a fast multilevel switching device, increasing information density in the same silicon area is a desirable feature. In this design and analysis, a unique memristor-based CMOS inverter is presented. A unique inverter with a nonvolatile output and good performance. This characteristic makes it useful for a substitute inverter as well as an SRAM memory cell that supports input negation for special uses. Memristor-based CMOS design is an emerging concept that targets efficient memory computing systems. Simulations were performed in cadence using a memristor model extracted to analyze and compare power consumption. The analyses of non-volatility, the voltage produced, and read/write period were performed with cadence virtuoso 130 nm CMOS technology using a power supply voltage of 1.9 V while consuming 35.67 µW, and the delay is 9.235 ps. The comparsion with a pure CMOS implementation is promising in terms of power, area and delay significant improvement. Further, the Monte Carlo simulation results using 2000 samples confirmed the total power and delay of the proposed design. [ABSTRACT FROM AUTHOR]

• The DC side voltage level of the system has been continuously improved in PV and PEDF system, it has developed towards DC3000V. This puts forward new requirements to higher voltage (>DC1500 V) DC circuit breakers for DC side short-circuit fault protection. Based on this, a self-powered hybrid DC circuit breaker with synergistic effect of step-down and divided current is proposed, which uses the voltage of the main branch to trigger IGBT conduction that can achieve commutation without additional trigger circuit. The interruption characteristics is analyzed by simulation. The voltage division of the reactor and the shunt function of the shunt resistance during the fault breaking process can not only reduce the current peak of the main branch and the transfer branch, but also greatly reduce the voltage that the mechanical switch needs to withstand, reduce the probability of post-arc reignition, and shorten the interruption time of the circuit breaker. The circuit breaker topology proposed in this paper can realize the interruption of the DC arc at larger fault current and higher voltage. It provides guidance for hybrid DC circuit breaker used to complete fault interruption in renewable energy power systems. The DC voltage level of photovoltaic and PEDF applications have continuously advanced, reaching up to DC3000V. This presents new requirements for DC circuit breakers operating at higher voltages (>DC1500V) to ensure effective fault protection in the DC side. Based on this, a self-powered hybrid DC circuit breaker with synergistic effect of step-down and divided current is proposed. This innovative design utilizes the voltage of main branch to trigger IGBT conduction, eliminating the need for an additional trigger circuit. The interruption characteristics is analyzed by simulation. The reactor and shunt resistance effectively reduce the peak currents of both main and transfer branches. This approach significantly mitigates the voltage stress on the mechanical switch, reduces the risk of post-arc reignition, and shortens the interruption time. The circuit breaker topology proposed enables the DC arc interruption at larger current and higher voltage, serving as the valuable guide for the implementation of hybrid DC circuit breakers in renewable energy power systems. [ABSTRACT FROM AUTHOR]

• Bi-directional power electronic switches enable a rapid and flexible conversion between low reactance in non-current-limited mode and high reactance in current-limited mode, suppressing the development of DC faults while achieving current limitation during mechanical switch opening. • The energy absorbed by the MOV is reduced. • DC opening time is shorter. • The proposed DCCB has economic advantages. The DC circuit breaker (DCCB) is a critical device that ensures the safe and reliable operation of the DC transmission system. As the level of DC voltage and transmission power increases, the flexible DC grid will need more and more opening capacity of the DCCB, as well as the burden of high costs. To solve the problem of excessive voltage and current stresses in existing DCCBs during DC fault current opening, an Improved Hybrid DCCB with the capacity of current-limiting and voltage-limiting is proposed, which crucially adds current-limiting and voltage-limiting branches. The current limiting branch can be activated 2 ms earlier in a fault circuit, significantly reducing the number of diodes and IGBTs required for branch transfer. In addition, overvoltage problems can be greatly reduced by properly designing the parameters of the current limiting branch. These improvements significantly increase the open ability, safety, reliability, and economy of the DCCB. The improved hybrid DCCB is shown to be effective and feasible by a large number of simulation and experimental test results. [ABSTRACT FROM AUTHOR]

The "LiCo x Ni y Mn 1-x-y O 2 -LiFePO 4 " hybrid battery pack is employed to mitigate drawbacks and fully leverage the distinct advantages of these two types of cells. Nonetheless, the fundamental statistics of the two types of cells diverge significantly, and the different cell configurations lead to the different output performances of the hybrid battery pack. Therefore, the different capacity and initial electricity thresholds configurations of the hybrid battery pack for various configurations are researched to achieve the diverse output performances. Firstly, a new approach based on electrochemical equivalent circuit model is introduced to simplify the parameter calibration process. Secondly, a series-connected hybrid battery pack simulation model with electrical-thermal-aging coupling is established to achieve the high-precision of capacity and aging simulation, which effectively replaces the physical experiments. Finally, the unchanged available electricity theory of the hybrid battery pack under a wide range of temperature scenarios is constructed based on the configurations of heterogeneous cells under different configuration, which provides a reference to the development of equalization algorithms. Furthermore, even if the aging rate of the heterogeneous cells is inconsistent, the configuration of the hybrid battery pack still could maintain the consistent output characteristics. • A new approach based on electrochemical equivalent circuit model is introduce. • The concept of internal resistance reference value is proposed. • A series-connected hybrid battery pack simulation model with electrical-thermal-aging coupling is established. • The unchanged available electricity theory of the hybrid battery pack under a wide range of temperature scenarios is constructed. • The equal proportion capacity configuration is carried out according to the concept of equal proportion migration of the homozygous cell parameters. [ABSTRACT FROM AUTHOR]

• DC vacuum arc is extinguished directly under a transverse magnetic field generated by Halbach permanent magnets. • Experimental tests investigated the DC interruption capacity of the vacuum interrupter under the Halbach transverse magnetic field. • Observation experiments revealed the evolution and transient process of the DC vacuum arc. • Two topologies based on Halbach transverse magnetic field and their future applications in DC circuit breakers are proposed. The vacuum interrupter is the core component of the DC circuit breaker to ensure the vacuum arc is extinguished reliably. The objective of this paper is to propose a method for extinguishing a DC vacuum arc directly by using an over 400 mT uniform unidirectional transverse magnetic field (TMF). The TMF is generated by an annular Halbach array consisting of 8 permanent magnets. The evolution process and interruption characteristics of the DC vacuum arc under Halbach TMF are investigated experimentally. The experimental results reveal that the whole interruption process consists of two stages, namely, the stable stage and the unstable stage. The stable stage corresponds to the stagnation and aggregation of cathode spots, and the unstable stage corresponds to the arc motion and reignition. The arc motion and reignition lead to the irregular oscillation of the arc voltage. Meanwhile, lateral movement of the arc followed by a fall at the edge of the contacts is the key to the rapid drop in current. It is found that a large arc current leads to a long duration of the stable stage, while the critical current is proportional to the contact separating distance. The experimental results show that the DC interruption capacity of the vacuum interrupter under the Halbach TMF exceeds 500 V/ 830 A, 700 V/ 660 A, and 1200 V/ 370 A, respectively. At last, two topologies based on Halbach TMF vacuum interrupter for DC interruption are proposed, and their future applications in mechanical/ hybrid DC circuit breakers are discussed. [ABSTRACT FROM AUTHOR]

[Display omitted] • Developed a soft printed circuit named liquid metal-hydrogel hybrid printed circuit. • Form a soft and safe bioelectronic interface with soft tissues (∼1–30 kPa). • A high current density region can be formed between the two liquid metal ports. • Can achieve site-targeted electrical stimulation without liquid metal leakage. Soft printed circuits is a vital component in electronic devices, which is designed to connect electrical components to exert certain functions. However, the design and fabrication of soft printed circuits still suffer from significant limitations including interconnection difficulties among varying materials with different stiffness, intrinsically low conductivity of typical soft materials like hydrogels, and the multi-material assembly and integration issues involved in the wiring and encapsulation process. Here we report a novel design paradigm of a soft printed circuit termed as liquid metal (LM)-hydrogel hybrid printed circuit (LMH-HPC), in which highly conductive LM functions as electrical wires while hydrogel can simultaneously work as the electrical junction, encapsulation, and bio-interfacing. The whole LMH-HPC maintains completely mechanically adapted (∼1–30 kPa) to soft tissues. Based on this LMH-HPC, we design soft hybrid circuits with movable but stable electrical connections with conventional solid electrical components. Owing to the giant electrical conductivity difference between LM and hydrogel, the current through the hydrogel can be tuned with density distribution at the hydrogel junction, which can be further utilized as the soft and safe bioelectronic interfaces for applications such as soft electrical stimulators for excitable cells and tissues, and iontophoresis-assisted wound dressing for antibacterial therapy. Overall, this LMH-HPC may set up a multifunctional platform for the design of hydrogel electronic devices. [ABSTRACT FROM AUTHOR]

• A CAOC-MPHDCB is proposed by combining with the principle of controllable active oscillation and the MPHDCB based on negative voltage source, which can not only greatly cut down the total cost and operation loss, but also reduce the insulation requirement of commutation circuit. The CAOC only needs an energy storage capacitor to store several kV pre-charge voltage, and can generate a high voltage on a pulse capacitor after several oscillations. Like a NVS, the CAOC can generate a negative voltage on the transfer branch to accelerate the current commutating from the main branch into the transfer branch. In addition, the IGBT full-bridge in the CAOC only needs to withstand the pre-charge voltage with low amplitude at any time. The simulation results verify the effectiveness of CAOC-MPHDCB, and shows its great application prospect in the field of HVDC interruption. The hybrid high voltage DC circuit breaker (HDCB) is widely regarded as the most promising solution to the fault current interruption of VSC-based DC grids. However, because of a large number of power electronic modules connected in series in transfer branch, the cost of existing HDCBs are pretty high, which limiting their large-scale commercial application. In this paper, a novel multi-port hybrid high voltage DC circuit breaker commutated by controllable active oscillation circuit (CAOC-MPHDCB) is proposed. Based on the principle of controllable active oscillation, the proposed CAOC-MPHDCB can realize the reliable commutation and fast interruption of fault current while significantly reducing the total cost and operation loss. In addition, the CAOC-MPHDCB can not only isolate line faults that occur continuously in a short time, but also maintain system ring-network structure after isolating the faulty DC bus. The influencing mechanism of parameters on the performance of CAOC-MPHDCB are analysed in detail, and the selection methods of corresponding parameters are obtained. The simulation results show that the principle of CAOC-MPHDCB is effective and feasible. [ABSTRACT FROM AUTHOR]

Abstract A SiC fiber-reinforced composite containing a SiC-ZrB 2 mixed matrix (SiC f /(SiC-ZrB 2)) with high density and enhanced mechanical properties was fabricated. ZrB 2 at 5 or 40 vol% was added to a (SiC + C) slurry to be infiltrated into the voids of 2D woven Tyranno™-SA grade-3 fabrics by electrophoretic deposition. Subsequent hot pressing at 1300 °C and 10 MPa for 1 h, followed by liquid silicon infiltration (LSI) at 1600 °C for 5 h in an Ar atmosphere resulted in the formation of the reaction-bonded SiC matrix, which revealed a composite density close to 97%. SiC f /(SiC-ZrB 2) having open porosities of 0.2–0.6% showed peak strengths of 398 and 320 MPa for 5 and 40 vol% ZrB 2 addition, respectively. The large mismatch in the coefficient of thermal expansion and Young's modulus between the SiC and ZrB 2 phases was attributed to a reverse trend in the strength of composites. Brittle behavior of the composites in flexure can be explained by the strong bonding between the matrix and fibers formed by the reaction of interphase with molten Si during LSI. Strength retention after oxidation at 1000 and 1400 °C for 2 h was also compared in terms of ZrB 2 amount contained in the composites. [ABSTRACT FROM AUTHOR]

Mobile terminals are often in the dynamic environment of heterogeneous networks. For some reasons, they need to switch between different networks, namely vertical handover. At this moment, it is a very crucial issue for the mobile terminal to select the best suitable one rapidly from all detected alternative networks on condition that the selection result can avoid the ping-pong effect as much as possible. This paper proposes a heterogeneous network selection algorithm based on the combination of network attribute and user preference. Taking full account of user preferences for each candidate network and the actual situation of heterogeneous networks, the algorithm combines three typical MADM methods, namely FAHP, Entropy and TOPSIS. We first use FAHP to calculate the subjective weights of network attributes and the subjective utility values of all alternatives for four typical traffic classes, and then use Entropy and TOPSIS to respectively get the objective weights of network attributes and the objective utility values of all alternatives. Finally, according to the comprehensive utility value of every candidate network and a threshold, the most appropriate network, whose comprehensive utility value is maximum and greater than the corresponding value of the current network of the mobile terminal, is selected to access. The proposed algorithm not only avoids the one-sided nature of a single algorithm, but also dynamically adjusts the proportion of each algorithm in the final result according to the actual requirements. Simulation results indicate that the proposed algorithm can accurately select the optimal access network, significantly reduce the number of vertical handovers and provide the required QoS and QoE in terms of the quantified benefit from vertical handoff, compared with three existing hybrid algorithms. [ABSTRACT FROM AUTHOR]

Cloud computing provided a framework for seamless access to resources through network. Access to resources is quantified through SLA between service providers and users. Service provider tries to best exploit their resources and reduce idle times of the resources. Growing energy concerns further makes the life of service providers miserable. User’s requests are served by allocating users tasks to resources in Clouds and Grid environment through scheduling algorithms and planning algorithms. With only few Planning algorithms in existence rarely planning and scheduling algorithms are differentiated. This paper proposes a robust hybrid planning algorithm, Robust Heterogeneous-Earliest-Finish-Time (RHEFT) 1 Robust Heterogeneous-Earliest-Finish-Time (RHEFT). 1 for binding tasks to VMs. The allocation of tasks to VMs is based on a novel task matching algorithm called Interior Scheduling. The consistent performance of proposed RHEFT algorithm is compared with Heterogeneous-Earliest-Finish-Time (HEFT) 2 Heterogeneous-Earliest-Finish-Time (HEFT). 2 and Distributed HEFT (DHEFT) 3 Distributed HEFT (DHEFT). 3 for various parameters like utilization ratio, makespan, Speed-up and Energy Consumption. RHEFT’s consistent performance against HEFT and DHEFT has established the robustness of the hybrid planning algorithm through rigorous simulations. [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]

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]

• 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]

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]

Abstract: This paper presents research that investigated and implemented a hybrid integrated location tracking framework that was developed by integrating infrastructure based positioning systems and inertial navigation. The authors implemented this research by using the Personal Dead Reckoning positioning system to serve as the inertial navigation based positioning system. The primary contribution of the presented work is the development and implementation of the Integrated Tracking System algorithm which was implemented in two levels. At the first level, the Integrated Tracking System (ITS) was developed by integrating Global Positioning System (GPS) and Personal Dead Reckoning (PDR) system to ubiquitously track a mobile user, in dynamic environments where GPS coverage may be uncertain. At the second level, the PDR system was integrated with a database of pre-determined known indoor location points in order to correct the accumulated drift error during a mobile user’s navigation in an indoor environment. Finally, a hybrid tracking system was developed and implemented by integrating the PDR system with the mobile user’s intervention and discernment of the environment. The implementation and the results obtained from validation experiments performed on the aforementioned hybrid tracking systems demonstrate the potential of using hybrid tracking for determining the spatial context of mobile users in ubiquitous context-aware engineering applications. [Copyright &y& Elsevier]

• A method is proposed to improve the fuel economy of a neighborhood electric vehicle. • A schematic of hybrid circuit and a method to decide mode change speed are proposed. • The hybrid circuit increased the motor efficiency by up to 14%. • The hybrid circuit improved the fuel economy of the vehicle by up to 3.8%. Increasing the low mileage associated with electric vehicles is a major requirement. Improving the efficiency of the traction motor is one solution to solve the mileage problem. In this study, we propose a method to improve the efficiency of a wound field synchronous motor (as the traction motor) in case of neighborhood electric vehicles. The wound field synchronous motor is a salient pole machine that generates a negative reluctance torque when operating in the second quadrant, reducing its efficiency. However, second quadrant operation is inevitable due to voltage limitation in the high-speed range. Here, we propose a hybrid circuit comprising U, V, W windings and X, Y, Z windings. The high-speed efficiency of the wound field synchronous motor is improved by changing the connection between the windings. Further, a neighborhood electric vehicle with a wound field synchronous motor was simulated using an advanced vehicle simulator (ADVISOR) to verify the proposal. The hybrid circuit increased the fuel economy of the electric vehicle by up to 3.8%. Finally, a validation experiment was conducted using a fabricated motor prototype. [ABSTRACT FROM AUTHOR]

Abstract: This paper investigates the effects of parameters on femtosecond laser ablation of Al2O3 ceramics. Ceramic alumina (Al2O3) is an important substrate used in hybrid circuits. Generally it is a difficult-to-cut material by conventional drilling and cutting procedures. Laser is suitable for precise form processing on hard or brittle ceramic materials, and with the increasing availability of femtosecond pulse lasers, the interest in using femtosecond laser ablation to produce precise, well-defined micrometer-sized structures in the ceramic materials is increasing. The laser parameters and material properties play an important role in the quality and efficiency of ceramics processing. This work develops a model to investigate parametric effects on femtosecond laser ablation of Al2O3 ceramics. The ablation depth and squared crater diameter per pulse predicted by this study are in agreement with the available experimental data. The effects of laser parameters and material properties on femtosecond laser ablation of Al2O3 ceramics are also discussed. [Copyright &y& Elsevier]