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The existing I2C interfaces require significant CPU intervention for data communication. In SOC systems, when using internally integrated I2C modules as masters, software control of I/O ports is necessary to emulate the I2C protocol for data transmission. This paper proposes a Mini I2C bus interface circuit design scheme that supports both master and slave modes. The I2C interface features minimal CPU intervention during data transmission, ease of use, small circuit area, and low power consumption. Additionally, the internal state machine design employs independent finite state machines (FSMs) for master and slave modes, enabling flexible configuration of the I2C module to operate in either mode. In comparison to reference (ShenZhen in Microelectronics Technology CO.BJ8M306A, Datasheet.2019.12.2., 2019), the proposed I2C solution reduces CPU instructions by 50% during data transmission, and by 33% compared to reference (GigaDevice Semiconductor Inc. GD32F1x0, Datasheet, 2022). After DC synthesis, the proposed design occupies only 14% of the area and consumes only 3.6% of the power of the Open Source I2C Design (Forencich in verilog-i2c. GitHub repository. Retrieved from https://github.com/alexforencich/verilog-i2c, n.d.). Therefore, this design scheme is better suited for low-power systems. The proposed design was validated through simulation using Xilinx ISE 14.7 with a SPARTAN 3 FPGA model xc3s500e-5pq208, and finally implemented using Huahong 95 nm CMOS technology, demonstrating high integration and low power consumption. [ABSTRACT FROM AUTHOR]

A novel room temperature capacitive sensor interface circuit is proposed and successfully tested, which uses a modified all-pass filter (APF) architecture combined with a simple series resonant tank circuit with a moderate Q -factor. It is fashioned from a discrete inductor with small dissipation resonating with a grounded capacitor acting as the sensing element to obtain a resolution of Δ C ∼ 2 zF in a capacitance range of 10–30 pF. The circuit converts the change in capacitance to the change in the phase of a carrier signal in a frequency range with a central frequency set up by the tank circuit's resonant frequency and is configured to act as a close approximation of the ideal APF. This cancels out the effects of amplitude modulation when the carrier signal is imperfectly tuned to the resonance. The proposed capacitive sensor interface has been specifically developed for use as a front-end constituent in ultra-precision mechanical displacement measurement systems, such as accelerometers, seismometers, gravimeters and gravity gradiometers, where moving plate grounded air gap capacitors are frequently used. Some other applications of the proposed circuit are possible including the measurement of the electric field, where the sensing capacitor depends on the applied electric field, and cost effective capacitive gas sensors. In addition, the circuit can be easily adapted to function with very small capacitance values (1–2 pF) as is typical in MEMS-based transducers. [ABSTRACT FROM AUTHOR]

To expand the scale of spiking neural networks (SNNs), an interface circuit that supports multiple SNN cores is essential. This circuit should be designed using an asynchronous approach to leverage characteristics of SNNs similar to those of the human brain. However, the absence of a global clock presents timing issues during implementation. Hence, we propose an intermediate latching template to establish asynchronous nonlinear connectivity with multipipeline processing between multiple SNN cores. We design arbitration and distribution blocks in the interface circuit based on the proposed template and fabricate an interface circuit that supports four SNN cores using a full‐custom approach in a 28‐nm CMOS (complementary metal–oxide–semiconductor) FDSOI (fully depleted silicon on insulator) process. The proposed template can enhance throughput in the interface circuit by up to 53% compared with the conventional asynchronous template. The interface circuit transmits spikes while consuming 1.7 and 3.7 pJ of power, supporting 606 and 59 Mevent/s in intrachip and interchip communications, respectively. [ABSTRACT FROM AUTHOR]

Electronic power converters are widespread and crucial components in modern energy scenarios. Beyond mere electrical energy conversion, their electronic structure allows several functionalities to be naturally embedded in them, including energy management, diagnosis, communication, etc. The operation of the converter itself, or the system interfaced by the same, commonly produces undesired electromagnetic interferences (EMIs) that should comply with prescribed limits. This paper presents a digital active EMI filter designed to mitigate such disturbances. The proposed hardware implementation can acquire and analyze the common-mode (CM) noise affecting the circuit and inject a compensation signal to attenuate the measured interference. A novel adaptive algorithm is introduced to compute the necessary signals for effective noise cancellation. The implementation is integrated within a single printed circuit board interfaced with a field-programmable gate array (FPGA) running the control algorithm. The digital filter's efficacy in EMI reduction is demonstrated using a synchronous buck converter with gallium nitride (GaN) power devices, achieving significant noise reduction. Additionally, potential functionalities are envisioned to fully exploit the capabilities of the proposal beyond EMI filtering, like fault detection, predictive maintenance, smart converter optimization, and communication. [ABSTRACT FROM AUTHOR]

Copyright of Technisches Messen is the property of De Gruyter and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Eddy current sensors are increasingly being used to measure the dynamic blade tip clearance in turbines due to their robust anti-interference capabilities and non-contact measurement advantages. However, the current research primarily focuses on enhancing the performance of eddy current sensors themselves, with few studies investigating the influence of turbine rotor parameters on the measurements taken by these sensors for dynamic blade tip clearance. Hence, this paper addresses this gap by using COMSOL Multiphysics 6.2 software to establish a finite model with circuit interfaces. Additionally, the model's validity was verified through experiments. This model is used to simulate the voltage output of the sensor and the measurement of dynamic blade tip clearance under various rotor parameters. The results indicate that the length and number of blades, as well as the hub radius, significantly affect the sensor voltage output in comparison to rotation speed. Furthermore, we show that traditional static calibration methods are inadequate for measuring dynamic blade tip clearance using eddy current sensors. Instead, it is demonstrated that incorporating rotor parameters into the calibration of eddy current sensors can enhance the accuracy of dynamic blade tip clearance measurements. [ABSTRACT FROM AUTHOR]

This work presents a novel compact CMOS potentiostat-designed circuit for an electrochemical cell. The proposed topology functions as a circuit interface, controlling the polarization of voltage signals at the sensor electrodes and facilitating current measurement during the oxidation–reduction process of an analyzed solution. The potentiostat, designed for CMOS technology, comprises a two-stage amplifier, two current mirror blocks coupled to this amplifier, and a CMOS push–pull output stage. The electrochemical method of cyclic voltammetry is employed, operating within a voltage range of ±0.8 V and scan rates of 10 mV/s, 25 mV/s, 100 mV/s, and 250 mV/s. The circuit is capable of reading currents ranging from 10 µA to 500 µA. Experimental results were obtained using a potassium ferrocyanide K3[Fe(CN)6] redox solution with concentrations of 10, 15, and 20 mmol/L, and their corresponding voltammograms were evaluated. The experimental results from a discrete circuit demonstrate that the proposed potentiostat topology produces outcomes consistent with those of classical topologies presented in the literature and industrial equipment. [ABSTRACT FROM AUTHOR]

The sensor that simultaneously perceives bending strain and magnetic field has the potential to detect the finger bending state and hand position of the human and robot. Based on unique magneto-mechanical coupling effect of magnetostrictive materials, the proposed a bi-perceptive flexible sensor, consisting of the Co–Fe film and magnetic sensing plane coils, can realize dual information perception of strain/magnetic field through the change of magnetization state. The sensor structure and interface circuit of the sensing system are designed to provide high sensitivity and fast response, based on the input–output characteristics of the simulation model. An asynchronous multi-task deep learning method is proposed, which takes the output of the position task as the partial input of the bending state task to analyze the output information of the sensor quickly and accurately. The sensing system, integrating with the proposed model, can better predict the bending state and approach distance of human or robot hand. [ABSTRACT FROM AUTHOR]

In this study, a neural network was developed for the detection of acetone, ethanol, chloroform, and air pollutant NO2 gases using an Interdigitated Electrode (IDE) sensor-based e-nose system. A bioimpedance spectroscopy (BIS)-based interface circuit was used to measure sensor responses in the e-nose system. The sensor was fed with a sinusoidal voltage at 10 MHz frequency and 0.707 V amplitude. Sensor responses were sampled at 100 Hz frequency and converted to digital data with 16-bit resolution. The highest change in impedance magnitude obtained in the e-nose system against chloroform gas was recorded as 24.86 Ω over a concentration range of 0–11,720 ppm. The highest gas detection sensitivity of the e-nose system was calculated as 0.7825 Ω/ppm against 6.7 ppm NO2 gas. Before training with the neural network, data were filtered from noise using Kalman filtering. Principal Component Analysis (PCA) was applied to the improved signal data for dimensionality reduction, separating them from noise and outliers with low variance and non-informative characteristics. The neural network model created is multi-layered and employs the backpropagation algorithm. The Xavier initialization method was used for determining the initial weights of neurons. The neural network successfully classified NO2 (6.7 ppm), acetone (1820 ppm), ethanol (1820 ppm), and chloroform (1465 ppm) gases with a test accuracy of 87.16%. The neural network achieved this test accuracy in a training time of 239.54 milliseconds. As sensor sensitivity increases, the detection capability of the neural network also improves. [ABSTRACT FROM AUTHOR]

In this paper, a novel digital closed-loop interface circuit system of MEMS vibrating gyroscope is proposed, which includes driving, detection and quadrature circuits. Because of the high sensitivity and precision of the MEMS gyroscope, the interface circuit system is established under the condition of mode separation. The driving circuit of MEMS gyroscope adopts digital automatic gain control (AGC) to realize self-excitation closed-loop control, which makes the gyroscope system simple in structure and good in robustness. First, the working principle of the gyroscope's sensitive structure is introduced and the system simulation model of the sensitive structure is developed. Second, a Σ Δ ADC and DAC with single-bit output are designed and the feasibility of the driving circuit design is verified by the system-level model. Third, the quadrature closed-loop correction circuit is designed to reduce the coupling of the quadrature component to the gyroscope detection circuit. The simulation results show that the quadrature correction loop can effectively reduce the influence of the quadrature coupling on the detection loop of MEMS gyroscope. Finally, the system-level model of the gyroscope is established by SIMULINK, the overall system performance of the gyroscope is analyzed, and the test system of MEMS gyroscope is built by field-programmable gate array (FPGA) and application specific integrated circuit (ASIC). The experiment verifies the feasibility of the digital interface circuit design, and the zero-bias instability of the gyroscope system is 1.0∘/h. [ABSTRACT FROM AUTHOR]

This paper presents a complete electromechanical (EM) model of piezoelectric transducers (PTs) independent of high or low coupling assumptions, vibration conditions, and geometry. The PT's spring stiffness is modeled as part of the domain coupling transformer, and the piezoelectric EM coupling coefficient is modeled explicitly as a split inductor transformer. This separates the coupling coefficient from the coefficient used for conversion between mechanical and electrical domains, providing a more insightful understanding of the energy transfers occurring within a PT and allowing for analysis not previously possible. This also illustrates the role the PT's spring plays in EM energy conversion. The model is analyzed and discussed from a circuits and energy harvesting perspective. Coupling between domains and how loading affects coupled energy are examined. Moreover, simple methods for experimentally extracting model parameters, including the coupling coefficient, are provided to empower engineers to quickly and easily integrate PTs in SPICE simulations for the rapid and improved development of PT interface circuits. The model and parameter extractions are validated by comparing them to the measured response of a physical cantilever-style PT excited by regular and irregular vibrations. In most cases, less than a 5–10% error between measured and simulated responses is observed. [ABSTRACT FROM AUTHOR]

Flexible and stretchable electronic devices are subject to failure because of vulnerable circuit interconnections. We develop a low-voltage (1.5 to 4.5 V) and rapid (as low as 5 s) electric welding strategy to integrate both rigid electronic components and soft sensors in flexible circuits under ambient conditions. This is achieved through the design of conductive elastomers composed of borate ester polymers and conductive fillers, which can be self-welded and generate welding effects to various materials including metals, hydrogels, and other conductive elastomers. The welding effect is generated through the electrochemical reaction-triggered exposure of interfacial adhesive promotors or the cleavage/reformation of dynamic bonds. Our strategy can ensure both mechanical compliance and conductivity at the circuit interfaces and easily produce welding strengths in the kilopascal to megapascal range. The as-designed conductive elastomers in combination with the electric welding technique provide a robust platform for constructing standalone flexible and stretchable electronic devices that are detachable and assemblable on demand. [ABSTRACT FROM AUTHOR]

Trans-impedance amplifier (TIA) based capacitance–voltage (C–V) readout circuits are widely used in micro-machined gyroscopes' control system. In this work, the noise performance of a TIA and charge sensitive amplifier (CSA) based C–V readout circuit is analyzed in detail. The theoretical derivation and simulation experiments carried out in this paper show that the thermal noise of high value feedback resistors in TIA dominates the output noise of the circuit, while a CSA-based readout circuit can overcome this shortcoming. Then, a CSA-based C–V readout circuit is designed with a 1.8 V transistor on a 180 nm complementary metal-oxide-semiconductor. This C–V-based readout circuit occupies an area of 0.039 mm2, which is smaller than the area of a 0603 package resistor. When 1 V bias voltage (Vb) is added to the capacitors under test, the tested C–V gain of this circuit is as high as 225 dB, and the tested output noise of the circuit is less than 150 n V / H z . Finally, the fabricated chip achieved a resolution of 840 z F / H z at Vb as low as 1 V. This CSA-based C–V readout circuit has more advantages in terms of noise and area over the TIA circuit and is more suitable for integration into the interface integrated circuit for micro-gyroscopes. [ABSTRACT FROM AUTHOR]

The acquisition of digital images is susceptible to haze, and images captured under such adverse conditions may impact high-level applications designed for clean input data. Image dehazing emerges as a practical solution to this problem, as it can be employed to pre-process images immediately after acquisition. This paper presents a concise review of impactful algorithms, including those based on deep learning models, to identify the existing gap in real-time processing capabilities. Subsequently, a real-time dehazing system on a multiprocessor system-on-a-chip (MPSoC) platform is introduced to bridge this gap. The proposed system balances the trade-off between dehazing performance and computational complexity; hence, the name "Symmetric" is coined. Additionally, the entire system is implemented in programmable logic and wrapped by an interface circuit supporting double-buffering, rendering it highly suitable for seamless integration into existing camera systems. Implementation results on a Zynq UltraScale+ MPSoC ZCU106 Evaluation Kit demonstrate a maximum operating frequency of 356.51 MHz, equivalent to a maximum processing speed of 40.27 frames per second for DCI 4K resolution. [ABSTRACT FROM AUTHOR]

The integration of the Arduino board into educational settings has penetrated across various educational levels. The teaching of this subject can be accomplished by (a) using real components in breadboards, (b) prefabricated modular boards that snap together, and (c) utilizing computer simulations. Yet, it is unknown which interface offers a more effective learning experience. Therefore, this experimental study aims to compare the effectiveness of these interfaces in a series of three laboratory exercises involving 110 university students, who were divided into three groups: (a) the first group used a tangible user interface, implementing circuits on breadboards, (b) the second group also used a tangible interface but with modular boards, and (c) the third group used a graphical user interface to simulate circuits using Tinkercad. For each laboratory exercise, students completed both pretests and posttests. Also, they provided feedback through five Likert-type attitude questions regarding their experiences. In terms of data analysis, t-tests, ANOVA, and ANCOVA, along with bootstrapping, and principal component analysis were employed. The results suggest that among the participants, those who used a graphical user interface stated that their understanding of the interconnection of components in microcontroller circuits was enhanced, while students with previous experience in microcontroller labs found the circuit creation process easier than students without experience. [ABSTRACT FROM AUTHOR]

As a promising energy‐harvesting technique, an increasing number of researchers seek to exploit the piezoelectric effect to power electronic devices by harvesting the energy associated with water flow. In this emerging field, a variety of research themes attract interest for investigation; these include selection of the excitation mechanism, oscillation structure, piezoelectric material, power management interface circuit, and application. Since there has been no comprehensive review to date with respect to the harvesting of water flow using piezoelectric materials, herein relevant work in the last 25 years is reviewed. To ensure that key aspects of the water‐flow energy harvester are overviewed, they are discussed in the context of energy‐flow theory, which includes the three stages of energy extraction, energy conversion, and energy transfer. The development of each energy‐flow process is reviewed in detail and combined with meta‐analysis of the published literature. Correlations between the harvesting processes and their contribution to the overall energy‐harvesting performance are illustrated, and directions for future research are also proposed. In this review, a comprehensive understanding of water‐flow piezoelectric energy harvesting is provided and it is aimed to guide future research and the development of piezoelectric harvesters for water‐flow‐powered devices is promoted. [ABSTRACT FROM AUTHOR]

A top-down design methodology and implementation of a time domain sensor is presented in this paper. The acceleration resolution of the time domain sensor is equal to the time-measurement accuracy divided by the sensor sensitivity. Combined with the sensitivity formula, the acceleration resolution is proportional to the vibration amplitude, the time-measurement accuracy, and the third power of the resonant frequency. According to the available time-measurement accuracy and the desired acceleration resolution, the parameters including the vibration amplitude and the resonant frequency were theoretically calculated. The geometrical configuration of the time domain sensor device was designed based on the calculated parameters. Then, the designed device was fabricated based on a standard silicon-on-insulator process and a matched interface circuit was developed for the fabricated device. Experimental results demonstrated that the design methodology is effective and feasible. Moreover, the implemented sensor works well. In addition, the acceleration resolution can be tuned by adjusting the time-measurement accuracy and the vibration amplitude. All the reported results of this work can be expanded to other time domain inertial sensors, e.g., a gyroscope or tilt sensor. [ABSTRACT FROM AUTHOR]

Half-flux-quantum (HFQ) logic is a superconductor logic family comprising conventional Josephson junctions (0-JJs) and π Josephson junctions (π-JJs). The energy scale of HFQ logic can be flexibly reduced by phase shifts owing to π-JJs; thus, HFQ circuits are a promising building block for qubit interface circuits. In this study, we demonstrate an NbN-based HFQ circuit element compatible with NbN-based superconducting qubits for all-NbN monolithic integration of qubits and HFQ circuits. The use of NbN is beneficial for both qubits and HFQ circuits owing to its high-quality junctions and high kinetic inductance. First, we developed a prototype of an NbN-based 0-JJ/π-JJ hybrid fabrication process for designing HFQ circuits. We evaluated 0-JJs and π-JJs fabricated through the hybrid process, which demonstrated that the 0-JJs had a small deviation with regard to critical current density and the π-JJs had a sufficiently high critical current density to work as π phase shifters. Furthermore, we fabricated an HFQ superconducting quantum interference device, which is one of the most fundamental elements in HFQ circuits, and observed clear HFQ-period modulation in the magnetic flux dependence of the maximum current at 4.2 K. [ABSTRACT FROM AUTHOR]

[Objective] Intelligent Sensing Engineering is an emerging discipline that responds to the ongoing technological revolution and industrial transformation. Established with a focus on meeting the national demands in emerging industries, this interdisciplinary field is a significant research topic for the development of intelligent sensing education. The design of sensor courses holds a key position in the curriculum, serving as a vital link between foundational and advanced concepts. The traditional sensor course at our institution primarily addresses the design and development of analog sensor interface circuits for Pt100 resistance temperature detectors. However, the fixed experimental procedures and a singular approach have impacted student enthusiasm in this regard. In contrast, flexible sensors, as a novel technology with broad innovation potential, have become a driving force in the era of intelligent sensing. Hence, incorporating the design of sensors in the curriculum has become imperative to familiarize students with the structures and system design concepts of new types of flexible sensors, such as graphene-based sensors. To cultivate students' abilities for independent learning, practical application, innovation, and solving complex engineering problems, a comprehensive course was designed. [Methods] This course integrates the production of flexible sensors, the construction of measurement circuits, data processing methods, and system calibration. Through this course, students can explore new application areas, design innovative intelligent sensing devices, and develop creative thinking and problem-solving skills. The goal is to enhance students' comprehensive skills and knowledge across multiple disciplines, covering the design of sensitive elements, conversion components, and conversion circuitry. The course also explores the manufacturing of flexible sensors using advanced materials, providing an in-depth understanding of the working principles and current production philosophies of advanced flexible sensors. By integrating knowledge from electronic engineering, materials science, and mechanical engineering, the course aims to foster students' holistic competence. Practical exercises allow students to foster hands-on skills, independent critical thinking, and problem-solving abilities, thus cultivating talents with enhanced innovation, engineering practice, and research capabilities. [Results] Compared to graphene, graphite, owing to its electrical properties being less influenced by various factors, is less common in the production of standard sensors. However, its layered structure and ease of cutting and bending make it convenient for students to personalize their creations within the sensor system. In contrast to mature standardized sensors, the performance of graphite flexible sensors is influenced by additional factors, such as environmental temperature, graphite purity, cross-sectional area, and length. This complexity provides students with opportunities to develop problem-solving skills, exercise variable control, and enhance data processing capabilities, merging theoretical sensor knowledge with practical applications. The designed course on graphite flexible pressure sensors effectively improves the teaching methods in the new field of Intelligent Sensing Engineering. [Conclusion] This innovative teaching approach not only increases the student's interest in the course but also develops their ability to think innovatively using acquired knowledge. Moreover, the design of this course effectively hones students' practical innovation skills, making them more competitive in the job market. Furthermore, it helps meet the growing demand for talent in the field of Intelligent Sensing Engineering. In addition, being abreast with the cutting-edge technologies in the field, students gain detailed insights into the latest research findings, thus laying a solid foundation for subsequent research work for both senior undergraduate and graduate students. [ABSTRACT FROM AUTHOR]

This paper presents a digital microfluidic (DMF) platform based on a printed circuit board (PCB) for droplet mixing. Mixing droplets without a top cover plate is important for bio-chemical analysis. For this reason, a more efficient mixing method is required especially for mixing a viscous liquid droplet in an open surface. Here, to improve the performance of droplet mixing, we propose the integration of an acoustically oscillating bubble to an electrowetting-on-dielectric (EWOD) chip, which can generate microstreaming inside the droplet. Firstly, an EWOD chip integrated with through-holes for bubble trapping was designed and fabricated through PCB fabrication. This PCB manufacturing technology helps to place more electrodes in the limited chip size. Secondly, we developed the custom-made circuit and interface to individually control multiple actuators (including EWOD actuation and acoustic excitation). Finally, an operation test was conducted to evaluate the capability of not only droplet transportation but also mixing on an open surface. The proposed PCB-based DMF platform for bubble-induced droplet mixing was experimentally verified and expected to make DMF chips more efficient when used for clinical point-of-care diagnostic applications. [ABSTRACT FROM AUTHOR]

The MEMS sensor converts the physical signal of nature into an electrical signal. The output signal of the MEMS sensor is so weak and basically in the low-frequency band that the MEMS sensor interface circuit has a rigorous requirement for the noise/offset and temperature coefficient, especially in the bandgap reference block. However, the traditional amplifier has low-frequency noise and offset voltage, which will decrease the precision of the bandgap reference. In order to satisfy the need of the MEMS sensor interface circuit, a high-precision and low-noise bandgap reference is proposed in this paper. A novel operational amplifier with a chopper-stabilization technique is adopted to reduce offset and low-frequency noise. At the same time, the V-curve compensation circuit is used to realize the second-order curvature compensation. The circuit is implemented under the 0.18 μm standard of the CMOS process. The test result shows that the temperature coefficient of the bandgap is 2.31 ppm/°C in the range of −40–140 °C, while the output voltage noise is only 616 nV/sqrt(Hz)@1 Hz and the power-supply rejection ratio is 73 dB@10 kHz. The linear adjustment rate is 0.33 mV/V for supply voltages of 1.2–1.8 V at room temperature, the power consumption is only 107 μW at 1.8 V power supply voltage, and the chip active area is 0.21 × 0.28 mm2. [ABSTRACT FROM AUTHOR]

When remote sports injuries are traditionally monitored, the feedback is not timely, and there are some problems such as low running speed and poor accuracy of sports injury monitoring. Therefore, this paper designs a remote sports injury monitoring method based on a wireless sensor network. Firstly, the terminal node of the sports injury monitoring process is designed, and three-terminal devices are tied to the experimental object's body to collect motion information, to realize the collection of human motion information based on ZigBee wireless sensor network; Secondly, the USB module circuit interface is designed to realize the series connection of each line, and the local processing ability of network nodes is used to make a centralized decision. Then, the skeleton coordinate system is constructed, and the rotation of the human skeleton is measured by an inertial sensor. Through a variety of posture fitting, the error of remote sports injury monitoring is reduced from the two directions of joint error and muscle error. Finally, the training sample set is learned through the BP algorithm, the fitness function of the genetic algorithm is obtained, the external structural parameters of the adaptive neural network model are adjusted, the discrimination deviation and fitness function are calculated, the adaptive neural network model with the best generalization ability is output, and the local processing ability of remote sports injury monitoring method is improved combined with wireless sensor network technology, The design of remote sports injury monitoring method based on wireless sensor network is realized. The experimental results show that the accuracy of the method is 99%, the average time delay is 1 s, and the accuracy of the method is 92% even with noise. Therefore, the method can effectively improve the running speed of the remote sports injury monitoring method and improve the accuracy of sports injury monitoring. [ABSTRACT FROM AUTHOR]

In this paper a design and application of corpus in computational linguistics is proposed based on multimedia technology in order to solve the problem of the combination of corpus technology and multimedia teaching methods. The hardware interface circuit is created based on the USB interface board, and the S3C6410 CPU is chosen to build a multimedia embedded processor. The proposed study is primarily concerned with creating and using a corpus for computational linguistics that is based on multimedia virtual technology. Multimedia virtual technologies will be employed in this study to set up an environment that is appropriate for gathering and analyzing linguistic data. The goal is to offer a language analysis method that is more effective and efficient, as standard approaches have trouble dealing with complex and varied data sources. The accuracy, scope, and variety of the language data are anticipated to be improved by the suggested methodology. The research also suggests a possible way to improve the Corpus's design and use in computational linguistics. In this study, encouraging results and an in-depth examination of important issues, such as reliability, validity, and efficiency, are examined. These issues should be measured when considering whether adopting a new technology is the right decision. According to the testing findings, the authors' shared system had the least reaction time-about 1.9 seconds. Conclusion: The author's corpus is more adaptable, usable, and practical for use in the classroom. [ABSTRACT FROM AUTHOR]

Mechanical vibrational energy, which is provided by continuous or discontinuous motion, is an infinite source of energy that may be found anywhere. This source may be utilized to generate electricity to replenish batteries or directly power electrical equipment thanks to energy harvesters. The new gadgets are based on the utilization of piezoelectric materials, which can transform vibrating mechanical energy into useable electrical energy owing to their intrinsic qualities. The purpose of this article is to highlight developments in three independent but closely connected multidisciplinary domains, starting with the piezoelectric materials and related manufacturing technologies related to the structure and specific application; the paper presents the state of the art of materials that possess the piezoelectric property, from classic inorganics such as PZT to lead-free materials, including biodegradable and biocompatible materials. The second domain is the choice of harvester structure, which allows the piezoelectric material to flex or deform while retaining mechanical dependability. Finally, developments in the design of electrical interface circuits for readout and storage of electrical energy given by piezoelectric to improve charge management efficiency are discussed. [ABSTRACT FROM AUTHOR]

As a promising energy‐harvesting technique, an increasing number of researchers seek to exploit the piezoelectric effect to power electronic devices by harvesting the energy associated with water flow. In this emerging field, a variety of research themes attract interest for investigation; these include selection of the excitation mechanism, oscillation structure, piezoelectric material, power management interface circuit, and application. Since there has been no comprehensive review to date with respect to the harvesting of water flow using piezoelectric materials, herein relevant work in the last 25 years is reviewed. To ensure that key aspects of the water‐flow energy harvester are overviewed, they are discussed in the context of energy‐flow theory, which includes the three stages of energy extraction, energy conversion, and energy transfer. The development of each energy‐flow process is reviewed in detail and combined with meta‐analysis of the published literature. Correlations between the harvesting processes and their contribution to the overall energy‐harvesting performance are illustrated, and directions for future research are also proposed. In this review, a comprehensive understanding of water‐flow piezoelectric energy harvesting is provided and it is aimed to guide future research and the development of piezoelectric harvesters for water‐flow‐powered devices is promoted.

As a common interface circuit for renewable energy integrated into the power grid, the inverter is prone to work under a three-phase unbalanced weak grid. In this paper, the instability of grid-connected inverters under the unbalanced grid condition is investigated. First, a dual second-order generalized integrator phase-locked loop (DSOGI-PLL)-based inverter under balanced and unbalanced conditions is modeled. A fourth-order impedance model is established to describe its impedance characteristics under the unbalanced grid condition. To analyze this multi-input multi-output system, a simplified stability analysis method based on the generalized Nyquist stability criterion and matrix theory is proposed. Then, the influences of circuit and control parameters on the stability of the grid-connected inverter system under the unbalanced grid condition are investigated. Finally, the accuracy of the derived frequency-coupled impedance model is verified via simulations, and the effectiveness of the proposed simplified stability analysis method on the system stability analysis is verified via both simulations and hardware experiments. [ABSTRACT FROM AUTHOR]

The unique benefits of Fabry–Pérot resonators as frequency-stable reference cavities and as an efficient interface between atoms and photons make them an indispensable resource for emerging photonic technologies. To bring these performance benefits to next-generation communications, computation, and time-keeping systems, it will be necessary to develop strategies to integrate compact Fabry–Pérot resonators with photonic integrated circuits. In this paper, we demonstrate a novel reflection cancellation circuit that utilizes a numerically optimized multi-port polarization-splitting grating coupler to efficiently interface high-finesse Fabry–Pérot resonators with a silicon photonic circuit. This circuit interface produces a spatial separation of the incident and reflected waves, as required for on-chip Pound–Drever–Hall frequency locking, while also suppressing unwanted back reflections from the Fabry–Pérot resonator. Using inverse design principles, we design and fabricate a polarization-splitting grating coupler that achieves 55% coupling efficiency. This design realizes an insertion loss of 5.8 dB for the circuit interface and more than 9 dB of back reflection suppression, and we demonstrate the versatility of this system by using it to interface several reflective off-chip devices. [ABSTRACT FROM AUTHOR]

Micro-Electro-Mechanical System (MEMS) capacitive accelerometers have received extensive attention in recent years due to their excellent performance indicators; especially in the fields of noise, power consumption, and bias instability, great development and progress have been made. In the field of noise, effective noise reduction is achieved by introducing oversampling modulation technology combined with digital noise reduction technology. In power consumption, the power consumption of the accelerometer is effectively reduced by using the successive approximation structure in the interface circuit and using the finite state machine for precise control. In bias instability, the effects of temperature offset and zero-point drift are suppressed by using a hybrid topology connection structure in the interface circuit, and an effective reduction of bias instability is achieved. In this paper, the research and progress of MEMS capacitive accelerometer in the field of noise, power consumption and bias instability are reviewed, and the articles published in recent years are listed and summarized and prospected. [ABSTRACT FROM AUTHOR]

Copyright of Rolling Stock (1002-7602) is the property of Rolling Stock Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In this work, an interface circuit applied to resistive gas or chemical sensors is proposed. The interface circuit includes a detection front-end, a single-end to differential circuit, a successive approximation analog-to-digital converter (SAR ADC), and some reference auxiliary circuits. In detection front-end circuits, mirrored currents in a current mirror usually differ by several orders of magnitude. In order to ensure that the current mirror can be copied accurately, this work uses a negative feedback structure consisting of an operational amplifier and an NMOS tube to ensure that the V DS of the current mirroring tube remains consistent. Simulation results show that the replication error of the current mirror is 0.015%. The proposed interface circuit has a detection range of 10 Ω to 1 G Ω with a relative error of 0.55%. The current multiplication or divided technique allows the interface circuit to have a high sampling frequency of up to 10 kHz. The proposed circuit is based on a 180 nm CMOS process with a chip area of 0.308 mm 2 (723 μ m ∗ 426 μ m). The power consumption of the whole interface circuit is 3.66 mW when the power supply voltage is 1.8 V. [ABSTRACT FROM AUTHOR]

This paper presents a compact and efficient integrated interface circuit for piezoelectric energy harvesting. While state-of-the-art interface circuits require either an external inductor or a significant number of additional capacitors to achieve high voltage flip and thus improve power efficiency, the proposed Full Active Rectifier on Flipping Capacitor (FAR-FC) is based on a reduced set of flipping capacitors and an active rectifier to efficiently flip the voltage across the piezoelectric transducer. In addition, this optimized SSHC circuit reaches better power efficiency when the piezoelectric transducer operates under low mechanical excitation, i.e. when the open-circuit voltage of the piezoelectric transducer is V o c = 1 V , while usually V o c ≥ 2 V in literature. Furthermore, the FAR-FC supports piezoelectric transducers with higher inherent capacitance values compared to those usually reported in literature, which makes the circuit potentially suitable for a larger variety of applications. The interface circuit was designed and fabricated in a 0.35 μm CMOS process. Measurement results show that the voltage flip efficiency goes up to 90 % . It also reveals that the proposed FAR-FC circuit achieves power performance up to 5.64 × higher than a conventional full-bridge rectifier. [ABSTRACT FROM AUTHOR]

The traditional RFID reader module relies on a discrete original design. This design integrates a microcontroller, high-frequency RFID reader IC and other multiple chips onto a PCB board, leading to bottlenecks in cost, power consumption, stability and reliability. To align with the trend towards high integration, miniaturization and low power consumption in RFID reader, this paper introduces a fully integrated RFID Reader SoC. The SoC employs the open-source Cortex-M0 core to integrate the RF transceiver, analog circuits, baseband protocol processing, memory and interface circuits into one chip. It's compatible with ISO/IEC 14443 A-type and B-type and ISO/IEC 15693 transmission protocols and rates. Manufactured using a 0.18 μ m process, the chip is compatible with multiple standards. The optimized design of the digital baseband control circuit results in a chip area of only 11.95 mm 2 offering clear advantages in both area and integration compared to similar work. [ABSTRACT FROM AUTHOR]

Microcontroller education is attracting increasing attention owing to the widespread application of microcontroller-based systems. This study proposes the learning-by-doing approach. Rather than emphasizing a deep understanding of datasheets and register-level programming, the new teaching model focuses on microcontroller-based applications. During the pre-class, in-class, and post-class phases, students were instructed to practice writing subroutines or building circuits to interface external devices with a training board. A typical case study is presented to illustrate the detailed process of the proposed model. Feedback from students and teaching supervisors in the recent years has shown that the teaching approach coupled with the training board provides students with more opportunities to work on real equipment, which benefits both the grasp of the theoretical knowledge and improvement of practical skills. [ABSTRACT FROM AUTHOR]

In inductive power transfer (IPT) systems, the coil design is crucial since the power transfer efficiency (PTE) of IPT depends on the coil characteristics such as geometric shape, diameter, wire thickness, etc. The most commonly used technique for the coil is finite element analysis (FEA). Nevertheless, if there are more than two parameters to be designed, FEA design requires a long simulation time since the coil design problem is separated into a series of single-parameter optimization problems. Another issue of conventional FEA is difficulty in interfacing with circuit simulation. To mitigate this issue, a novel co-simulation framework of MATLAB/ANSYS Maxwell is proposed in this paper. In MATLAB, multi-dimensional optimization algorithms like scan-and-zoom are employed to determine geometric parameters to achieve high PTE and minimize the number of FEA executions while Maxwell serves to extract the circuit parameters from the geometric parameters and enhance the accuracy of calculation. The 100 W prototype IPT system is built to verify the proposed coil design scheme in this paper. The performance comparisons with the conventional methods in terms of design accuracy, simulation time, and application flexibility are performed on a pair of designed single-layer circular coils. [ABSTRACT FROM AUTHOR]

One of the elementary operations in computing systems is multiplication. Therefore, high-speed and low-power multipliers design is mandatory for efficient computing systems. In designing low-energy dissipation circuits, reversible logic is more efficient than irreversible logic circuits but at the cost of higher complexity. This paper introduces an efficient signed/unsigned 4 × 4 reversible Vedic multiplier with minimum quantum cost. The Vedic multiplier is considered fast as it generates all partial product and their sum in one step. This paper proposes two reversible Vedic multipliers with optimized quantum cost and garbage output. First, the unsigned Vedic multiplier is designed based on the Urdhava Tiryakbhyam (UT) Sutra. This multiplier consists of bitwise multiplication and adder compressors. Compared with Vedic multipliers in the literature, the proposed design has a quantum cost of 111 with a reduction of 94% compared to the previous design. It has a garbage output of 30 with optimization of the best-compared design. Second, the proposed unsigned multiplier is expanded to allow the multiplication of signed numbers as well as unsigned numbers. Two signed Vedic multipliers are presented with the aim of obtaining more optimization in performance parameters. DesignI has separate binary two's complement (B2C) and MUX circuits, while DesignII combines binary two's complement and MUX circuits in one circuit. DesignI shows the lowest quantum cost, 231, regarding state-of-the-art. DesignII has a quantum cost of 199, reducing to 86.14% of DesignI. The functionality of the proposed multiplier is simulated and verified using XILINX ISE 14.2. [ABSTRACT FROM AUTHOR]

Copyright of Piezoelectrics & Acoustooptics is the property of Piezoelectric & Acoustooptic and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

This article presents a wide-range and high-precision analog front-end circuit for multi-parameter sensors that can handle sensor outputs of different types (R, C, V). A rail-to-rail baseline compensation method has been proposed, which further incorporates a fine offset elimination of 0.6 mV/step. Additionally, self-zeroing and correlated double-sampling techniques are integrated to reduce low-frequency noise and offset, prevent sensor signal saturation, and enhance the precision of the analog front-end circuit. By incorporating variable components in the sensor signal acquisition circuit and integrating them with the baseline compensation circuit, the applicability range of the sensor has been expanded (R: 7 Ω –1.7 M Ω , C: 50 fF–35 pF, V: 0.05–1.7 V). Test results show all interface circuits exhibit significant total conversion gains (C: 45 mV/fF, R: 14.5 mV/ Ω , V: 144 V/V), achieving high precision. Meanwhile, a coefficient of determination ( R 2 ) greater than 0.998 indicates high conversion linearity of the circuit. [ABSTRACT FROM AUTHOR]

We have developed a micro-controller based Deep Level Transient Spectroscopy (DLTS) system to identify the deep-level defects in semiconductors. It consists of Arduino-Due, a capacitance meter, and interface circuits. In addition, we have also developed the algorithms needed for the entire signal processing. It is not limited to Arduino-Due but can be implemented using other micro-controllers also. We have used Arduino-Due to generate the filling pulse and monitor the capacitance, temperature, data acquisition, timing control, and signal processing. The sequence of generating the filling pulse, reading the data, and signal processing is controlled digitally rather than by analog sampling circuits and timers. The minimum pulse width generated using Arduino-Due is 50 ns; the pulse width generation depends on various hardware and software parameters and their integration. The resolution in reading the data is 0.8 mV/unit. The time delays in reading the data are appropriately taken care of in the system. The whole experiment can be completed in a single temperature cycle within 2–3 h. The system is simple, inexpensive, in an easy-to-use platform, and less time-consuming; minimizes possible errors; and improves accuracy. The measurements using the "micro-controller based DLTS system" are verified by fabricating (Au) gold-doped silicon (Si) p–n junction samples (Au is a well-understood defect in Si). Using the Arduino-Due based DLTS system, we calculated the energy, the capture cross section, and the concentration of trap levels. The results are in good agreement with the literature, indicating the versatility of the system. [ABSTRACT FROM AUTHOR]

In this paper, an interface circuit for far-distance energy harvesting from magnetic field of overhead lines is presented. Due to the specific conditions of this type of energy harvesting, such as low available power, low induced voltage in the energy harvester coil, and change of energy harvester impedance, a direct AC/DC switching converter should be used. A maximum power point tracking solution is also necessary to guarantee impedance matching at different operation points. Since the harvested power is in the range of a hundred micro-watts, the power usage of the control circuitry is of significant importance and conventional design approaches based on microcontrollers and FPGAs which require ADCs, DACs and digital signal processing cannot be applied here. The proposed processing circuitry presented in this paper uses three feedback loops to perform the harvesting and energy transfer control. Only low-power comparators and basic digital gates are used as signal-processing elements to limit the power dissipation of the designed control blocks. The impedance matching inner loop samples the H-bridge voltage drop to extract the output load current and perform PWM impedance matching while transferring a rectified current to the output capacitor. Another inner feedback loop is used at the output capacitor using two-level comparison to regulate the output voltage. For maximum power point tracking an outer feedback loop samples the output voltage transfer rate and using a 50 Hz reference generator, adjusts the parameters of the impedance matching circuit of the first inner loop. With the proposed approach, in addition to converting the AC input power to a DC voltage, the output load is regulated at a fixed potential and using the MPPT control loop, the maximum power available from the coil is delivered to the output with relatively low dissipation. The proposed circuit is evaluated using a 0.18 μm standard CMOS technology and operates as a self-powered circuit without an external power source. Based on the obtained results, the efficiency of the proposed circuit at 119 µW input power is about 92.4%, and the MPPT efficiency is about 95%, which is suitable for low-power applications. [ABSTRACT FROM AUTHOR]

Copyright of Railway Signalling & Communication Engineering is the property of Railway Signalling & Communication Engineering and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In this paper, we propose a design support tool set for interface circuits between synchronous and asynchronous modules. To facilitate the design of interface circuits between synchronous and asynchronous modules, the proposed tool set generates interface circuits and design constraints based on a predefined communication scheme. In addition, the proposed tool set performs timing verification and delay adjustment to guarantee the operations of the generated interface circuits. In the experiment, we evaluated the latency and overhead of the generated interface circuits. The latency and handshake overhead of the interface circuits generated by the proposed tool set depend on the cycle time of the receiver module. In addition, we designed a system which consists of a synchronous RISC-V processor and an asynchronous multilayer perceptron (MLP) circuit using the proposed tool set. The energy consumption of the system was reduced by 34.0% compared with a system which uses a synchronous MLP circuit.

Energy harvesting from structural vibrations of civil structures using piezoelectric elements has emerged as a promising renewable source for generating power for microelectronic devices such as wireless sensor nodes (WSNs) deployed for structural health monitoring (SHM), sustainable transportation, Internet of Things (IoTs), etc. In recent past, several innovations have been achieved in this field by giving attention to either the associated interface electronics circuits or structural configurations. Yet, a notable gap appears in the field on the effective rectifier circuits suitable for low-frequency structural vibrations, which are often erratic in nature. This paper addresses practical issues involving non-sinusoidal, low-frequency (2–15 Hz) and small voltage amplitude (1–2 V) vibration sources found in civil-structures for piezoelectric energy harvesting (PEH). The paper presents an experimental investigation for comparing the performance of passive rectifier circuits, namely the full bridge, the gate cross-coupled, and the full gate cross-coupled type circuits to evaluate their relative performance for harvesting energy in real-life structures. Experimental results show that D1000 full bridge rectifier circuit outperforms other types of rectifying circuit at low as well as high frequencies. A charging efficiency of 81.33% has been achieved for 1 V open-circuit piezoelectric voltage at 5 Hz. Power in nano-watts range can be harvested from such real-life structural vibrations. [ABSTRACT FROM AUTHOR]

Recently, there has been considerable research interest in the potential for DC distribution systems in buildings instead of the traditional AC distribution systems. Due to the need for performing power conversions between DC and AC electricity, DC distribution may provide electrical efficiency advantages in some systems. To support comparative evaluations of AC-only, DC-only, and hybrid AC/DC distribution systems in buildings, a new modeling toolkit called the Building Electrical Efficiency Analysis Model (BEEAM) was developed and is described in this paper. To account for harmonics in currents or voltages arising from nonlinear devices, the toolkit implements harmonic power flow, along with nonlinear device behavioral descriptions derived from empirical measurements. This paper describes the framework, network equations, device representations, and an implementation of the toolkit in an open source software package, including a component library and graphical interface for creating circuits. Simulations of electrical behavior and device and system efficiencies using the toolkit are compared with experimental measurements of a small office environment in a variety of operating and load configurations. A detailed analysis of uncertainty estimation is also provided. Key findings were that a comparison of predicted versus measured efficiencies and power losses in the validation testbed using the initial toolkit implementation predicted device- and system-level efficiencies with reasonably good accuracy under both balanced and unbalanced AC scenarios. An uncertainty analysis also revealed that the maximum estimated error for system efficiency across all scenarios was 3%, and measured and modeled system efficiency agreed within the experimental uncertainty in approximately half of the scenarios. Based on the correspondence between simulation and measurement, the toolkit is proposed by the authors as a potentially useful tool for comparing efficiency in AC, DC, and hybrid AC/DC distribution systems in buildings. [ABSTRACT FROM AUTHOR]

Purpose: The purpose of this research paper is to explore the possibility to enhance the power transfer from piezoelectric energy harvester (PEH) source to the load. As the proposed gyrator-induced voltage flip technique (GIVFT) does not require bulky components such as physical inductors, it is easily realizable in small integrated circuits (IC) package thereby offering performance benefits, reducing area overhead and providing cost benefits for constrained self-powered autonomous Internet-of-Things (IoT) applications. Design/methodology/approach: This paper presents an inductorless interface circuit for PEH. The proposed technique is called GIVFT and is demonstrated using active elements. The authors use gyrator to induce voltage flip at the output side of PEH to enhance the charge extraction from PEH. The proposed technique uses the current-voltage (I-V) relationship of gyrator to get appropriate phasor response necessary to induce the voltage flip at the output of PEH to gain power transfer enhancement at the load. Findings: The experimental results show the efficacy of the GIVFT realization for enhanced power extraction. The authors have compared their proposed design with popular earlier reported interface circuits. Experimentally measured performance improvement is 1.86×higher than the baseline comparison of full-wave bridge rectifier circuit. The authors demonstrated a voltage flip using GIVFT to gain power transfer improvement in piezoelectric energy harvesting. Originality/value: To the best of the authors' knowledge, pertaining to the field of PEH, this is the first reported GIVFT based on the I-V relationship of the gyrator. The proposed approach could be useful for constrained self-powered autonomous IoT applications, and it could be of importance in guiding the design of new interface circuits for PEH. [ABSTRACT FROM AUTHOR]

In recent years, Micro-Electro-Mechanical Systems (MEMS) technology has had an impressive impact in the field of acoustic transducers, allowing the development of smart, low-cost, and compact audio systems that are employed in a wide variety of highly topical applications (consumer devices, medical equipment, automotive systems, and many more). This review, besides analyzing the main integrated sound transduction principles typically exploited, surveys the current State-of-the-Art scenario, presenting the recent performance advances and trends of MEMS microphones and speakers. In addition, the interface Integrated Circuits (ICs) needed to properly read the sensed signals or, on the other hand, to drive the actuation structures are addressed with the aim of offering a complete overview of the currently adopted solutions. [ABSTRACT FROM AUTHOR]