Miracle-dz/UniFAR-FTUs huggingface dataset:
Prediction of the Battery State Using the Digital Twin Framework Based on the Battery Management System

Electric Vehicles (EVs) reliance on batteries, which currently have lower energy and power densities than liquid fuels and are prone to aging and performance degradation over time, restricts their mainstream adoption. With applications like electric vehicles and grid-scale energy storage, effective management of lithium-ion batteries is a vital enabler for a low-carbon future. Monitoring the battery’s condition of health and charge over the lifetime of an EV is, therefore, a highly pertinent issue. Battery Management Systems (BMS) are used during the operation of EVs to monitor, estimate and control battery states to ensure that batteries can function effectively and safely. Additionally, the materials composition, system design, and operating circumstances substantially impact a battery’s usable life, making it more challenging to govern and maintain battery systems. This work proposes the structure of a battery digital twin-based battery for the electronic vehicle, which has the potential to enhance BMS situational awareness greatly and enable the optimal functioning of battery storage units. Digitalization and Artificial Intelligence (AI) present an opportunity and offer. In this paper, a Digital Twin (DT) is proposed as a solution to the difficulty of onboard computation for the incremental State Of Health (SOH) and State Of Charge (SOC) by using Extreme Gradient Boost (XGBoost) model and Extended Kalman Filter (EKF) to predict the state estimate for the EV battery. The battery’s condition has been determined by using the EKF, which can provide vital information for maintenance. First, the battery’s usable life can be extended with an accurate estimate of the SOC to continue; then a learning-based prediction approach to gauge the battery’s health state is suggested in order to increase battery life. A SOC model is frequently retrained to depict the effects of aging, and a SOH model is often performed to foretell the reduction in the highest battery capacity. According to a result, DT models are useful for managing batteries, and full life cycle statistics are important for planning the battery’s upgrade path.
Pairwise T-Test: Identification of Tonal Relations

This study established an empirical-analytical model to specify tonal relations in Asian tonal languages. Applying this model on the examination of field data from 21 speakers of Zhangzhou Southern Min derived a linguistically phonetic F0 system for its eight-way tonal contrasts in citation. The result represented this Southern Min dialect as an independent variety from the scientific perspective while making it comparable with other tonal varieties and languages for typological and universal purposes. The description has gone beyond the inconsistency and inadequacy of those earlier studies based on auditory impressions and has laid out a solid and objective foundation for further theoretical exploration in this dialect. It also contributed a scientific framework to examining the tonal property in other tonal languages in the hope of broadening and deepening our understanding of the typology of tone as an important linguistic phenomenon in Asia.
A Model Predictive Control for a Multilevel Inverter Fed Induction Motor Drive Based on Three-Phase Triple Inverter Modular Topology

Induction motor drives based on multilevel inverters have been established as a solution for many applications. Due to their interesting characteristics, several topologies have been proposed. One of the latest topologies is the one based on three-phase triple inverter modular topology. However, not much work has been realized regarding their control. Thus a field-oriented controller with a model predictive control (MPC) strategy to control this AC drive is proposed. The MPC will be used to control the AC currents of the inverter. One aspect that is inherent to this drive is the high number of voltage vectors. Thus, besides their predictive characteristic, this controller also shows their advantage dealing with this high number of voltage vectors. The capabilities of the proposed controller will be verified through a simulation study.
Analysis of chaotic characteristics of partial discharge in solid insulating material voids

Existing studies have shown that the partial discharge (PD) of solid insulating materials is not a simple random process, but a chaotic process. The chaotic characteristics can provide judgment basis in the development of PD and insulation breakdown warning. Therefore, it is necessary to further study the chaotic characteristics of PD. Based on the PD model and theoretical formula in the internal voids of insulating materials, this paper simulates the PD process under the conditions of charge decay time constant, initial electron generation rate and other parameters, obtains the two-dimensional spectrum similar to the experimental results, constructs the time series of pulse discharge and discharge time interval in the PD process, and constructs the chaotic attractor. The chaotic characteristics of PD are characterized by calculating the maximum Lyapunov exponent and other chaotic characteristic parameters. The results show that the chaotic characteristic parameters of PD time series are different under different conditions. In a certain range, the initial electron generation rate and conductivity affect the feedback mechanism of PD and the randomness of initial electrons, and directly affect the chaotic characteristics of PD. This conclusion lays a foundation for the further study of the chaotic mechanism of PD.
Testing for Stationarity in Heterogeneous Panel Data

This paper proposes a residual-based Lagrange multiplier (LM) test for a null that the individual observed series are stationary around a deterministic level or around a deterministic trend against the alternative of a unit root in panel data. The tests which are asymptotically similar under the null, belong to the locally best invariant (LBI) test statistics. The asymptotic distributions of the statistics are derived under the null and are shown to be normally distributed. Finite sample sizes and powers are considered in a Monte Carlo experiment. The empirical sizes of the tests are close to the true size even in small samples. The testing procedure is easy to apply, including, to panel data models with fixed effects, individual deterministic trends and heterogeneous errors across cross-sections. It is also shown how to apply the tests to the more general case of serially correlated disturbance terms.
Integrated System on a Chip for Guidewire IVUS

Although intravascular ultrasound (IVUS) provides real-time and high-resolution images of the arteries and it has become a significant imaging modality for cardiovascular interventions, its current implementations still have limitations in terms of accessing narrow and tortuous arteries. An IVUS system that can be realized on a guidewire can largely remedy these limitations. A significant aspect of guidewire IVUS is the integrated electronics. In this work, we present a practical integrated system-on-a-chip (SoC) for guidewire IVUS. The front-end circuitry has a 20-channel ultrasound transmitter (Tx) and receiver (Rx) array connected to a capacitive micromachined ultrasound transducer (CMUT) array. For communication between the front-end and back-end systems, an 8-channel flexible printed circuit (FPC) is used to meet the strict size requirements while presenting some challenges. To cancel the common noise, received signals are converted to the differential before being sent via the FPC. A 10 MHz sinewave is used as the clock source to reduce the crosstalk on the FPC which is recovered and frequency multiplied on-chip as the master clock. The SoC was fabricated in a 0.18 µm high voltage (HV) CMOS process, occupying a narrow active area of 0.3 mm × 3.6 mm and consuming 23.4 mW and 30.3 mW from LV and HV power supplies, respectively. The functionality of the integrated system-on-a-chip was verified by the CMUT/ASIC time domain test.
A Three-Port DC-DC-DC Converter based on Dual Active Bridge Series Resonant Topology for Electric Vehicle DC Fast Charging Applications

This paper proposes a three-port dc-dc-dc converter based on dual active bridge series resonant (DABSR) and interleaved boost topology that integrates PV, electric vehicle (EV) battery, and dc-link situated between ac-dc stage and dc-dc stage of the EV dc fast charger. The power flow between port-l (dc-link) and port-3 (EV battery) occurs due to the phase shift between input and output bridge switching of DABSR topology. We adopt triple phase shift (TPS) modulation that secures zero voltage switching (ZVS) of all the switches for a wide range of EV battery voltage and hence, overall efficiency is increased. The circuit works as an interleaved boost converter between port-l (dc-link) and port-2 (PV) while interrupting the power flow between port-l and port-3 with the proper selection of phase shift and duty cycles. The dc-link voltage remains constant during port-2 to port-3 power transport which also utilizes DABSR topology. Operating principles of different power flow modes have been discussed and simulation performed in Matlab/Simulink validates the feasibility of the proposed converter as the dc-dc power stage of the EV dc fast charger.
On diffusion of turbulent energy in plane Couette flow

This study addresses the possible existence of significant counter-gradient diffusion of turbulent energy from the centre towards the walls in plane Couette flow. Data from a direct numerical simulation disprove the counter-gradient diffusion hypothesis and reveal that the turbulent energy production is nearly balanced by the energy dissipation throughout the core region. The results of the simulation are more plausible than the most comprehensive set of measurements available today.
PPBAM:A Preprocessing-based Power-Efficient Approximate Multiplier Design for CNN

In the fields of CNN, there exists many multiply applications with one fixed operand. In view of such characteristics, this paper proposes a preprocessing-based power-efficient approximate multiplier (PPBAM) design for CNN. In the proposed design, the fixed operand is preprocessed to avoid additional dynamic power consumption due to repeated processing. To reduce the number of the partial products, the first ‘1’ of both two operands are found and then the operands are truncated by a method named weak rounding. What's more, a sub multiplier array utilizing an approximate 4:2 compressor are proposed to calculate the truncation results with low power. The experimental results show that, with the same accuracy, on average, our design has a 30% improvement in power consumption compared with state-of-the-art approximate multiplier designs without additional latency and area.
A Broadband and High Speed CML Divider with Inductor Peaking in 40-nm SMIC

High-frequency broadband current-mode logic static divider circuit fabricated in CMOS 40-nm is presented. In the proposed circuit, inductance peaking technology is utilized to improve the locking frequency and working bandwidth. The optimization strategy of frequency divider in detail is introduced, which can increase the locking range while maintaining low power consumption. The frequency divider can work in the frequency range of more than 20-54GHz, consume 6.48mw of power with a 1.2V power supply, and the core area is only 0.02mm2.
A comparison of two models to measure the distance decay of urban land density to the city center

As the distance to the city center increases, the density of urban land decays. The distance decay of urban land density can be quantitatively described by the urban land density function (also known as the inverse-S function) and the Geographic Micro-Process (GMP) model. However, the differences between the two models in the aspects of the fitting results and application scope are not clear. Taking Hefei as an example, this paper interpreted Landsat images to obtain land use data at three time points and combined the concentric-ring analysis method to compare the differences between the two models. The results show that the two models can both fit the distance decay of urban land density well, and both provide quantitative indicators for measuring urban compactness. However, the inverse-S function is an empirical model. Although it can describe the distance decay of urban land density and the urban expansion processes with higher accuracy, it cannot provide a mechanistic explanation. In contrast, the GMP model is a theoretical model derived based on explicit assumptions, which can reveal the reasons for the inverse-S shaped decay pattern of urban land density and the change of urban compactness from a process perspective. This study provides references for the method selection of fitting urban land density spatial decay and the modeling of urban land-use change.
Designing High Power Density Induction Motors for Electric Propulsion

Designing high-power-density electric motors for propulsion has become an increasingly important issue in the past few decades. This is not only because electric vehicles are projected to become the main private transportation means in near future, but also because of the ever so important metro and railway transport requirements. Along with these application areas, electric aircraft propulsion is also coming into focus in recent years. Electric motors for traction are required to have high torque density, high efficiency over a wide speed range and are required to be robust. In recent years, permanent magnet (PM) motors became the favorite choice for such applications because of their higher efficiency than other types of motors. Increasing demand for permanent magnets is likely to cause supply problems. Therefore, permanent magnet-free alternative motor types are of much interest. In this paper, the authors present the design of a 125 kW induction motor for railway application. This design has 3-times the power density of a commercial induction motor. The designed motor is manufactured and its test results are used for establishing an accurate finite-element model for the prediction of its performance. This model is used to investigate the effect of magnetic loading choice, slot shape and magnetic material choice on the efficiency of the motor. It is shown that with the same basic dimensions the efficiency of the motor can be increased to 96% which is comparable with a similar size PM motor.
A Low Frequency Drift LC-DCO with Wide Temperature Range

A 2.4GHz LC-DCO with low frequency drift is presented to support frequency synthesizer under narrow band system like BLE. In the LC-DCO, a comprehensive temperature compensation scheme, which includes a Proportional To Absolute Temperature (PTAT) current bias and the varactor arrays varying linearly with voltage, is proposed to reduces the frequency drift of LC-DCO as a result of temperature fluctuations. By applying the circuit, frequency drift is reduced from 31MHz (without compensation) to 6MHz within the temperature from -40°C to 120 °C. And the results show that no extra in-band noise is added to LC tank. It consumes 860uW from a 0.9V supply in 40nm CMOS process technology.
LOCOMOTIVE 5G Core for 6G ready Resilient and Highly Available Network Slices and SFCs

The presence of a Load Balancer (LB)s is much significant to keep up the High Availability (HA) and resilience of the scalable 5G Core (5GC). The whole system may collapse just because of inefficient LB at any NF, resulting in total disruption to the High Availability (HA) service. In this paper, we present the LOCOMOTIVE 5GC which outperforms the traditional hot standby in both HA and resilience during various dynamic conditions. LOCOMOTIVE serves 16% (at least) more user requests compared to hot standby in the control plane while handling unexpected overloaded conditions (without the failure of LB). During the failures of LB, it drops 22% lesser user requests than hot standby. With this outstanding resilience, LOCOMOTIVE even achieves 4% better availability than the hot standby in an active-active cluster configuration. To prove the feasibility of LOCOMOTIVE and to encourage further research works in the world of LBs, we developed its entire framework in a 3GPP compliant 5G test-bed system along with eXpress Data Path (XDP) and extended Berkeley Packet Filter (eBPF) framework.
Switching Frequency Modulation of a 27 kW DC-DC Converter with Si-IGBTs in Light-Load Operation

For power management, fuel cell hybrid vehicles use a DC-DC converter in front of the battery. In the literature, the authors recommend SiC-MOSFETs and present Si-IGBTs in DC-DC converters as power semiconductors with high losses, high volume, and poor thermal performance. However, high efficiencies are usually only achieved in the nominal power range. Moreover, in light-load operation, the efficiency of DC-DC converters decreases, whereby - according to the worldwide harmonized light vehicles test procedure - vehicles rarely operate in the nominal power range. Increasing the efficiency of DC-DC converters in light-load operation is possible by switching frequency modulation. For output powers above 10 kW and Si-IGBT modules, it is necessary to reduce the switching frequency to enhance efficiency as switching losses of Si-IGBTs usually dominate converter losses. However, by decreasing the switching frequency, DC-DC converters could reach discontinuous conduction mode, and in terms of controller design, it is crucial to avoid this operation mode. This paper shows that by using powder cores, switching frequency modulation for critical conduction mode is useful for DC-DC converters for power ranges above 10 kW. This study uses a 27 kW bidirectional cascaded buck and boost converter with Si-IGBT half-bridge modules to validate the proposed modulation method. In light-load operation, the results prove power loss improvement by up to 16% in buck mode and 33% in boost mode. However, the high core volume indicates that DC-DC converters based on Si-IGBTs for power ranges above 10 kW are unsuitable for fuel cell hybrid vehicles.
Research and application of operation field safety control based on YOLOv4 algorithm in Qt

Safe production is the basis of all the work of enterprises, the occurrence of any accident, will directly affect production activities, and even cause property losses and casualties, therefore, the safety management of enterprises is particularly important. Combined with the current situation of safety production management at construction sites in the power industry, the safety of construction sites is mostly managed by the person in charge of on-site construction, which is prone to the lack of safety control and control, forming safety hazards or causing safety accidents. In order to improve the safety management level of the construction site and realize the transformation from human control to automatic control of equipment, this paper proposes a kind of safety monitoring and early warning based on network video to build production site, which is applied to on-site safety management. Through the inspection and survey of transmission ground line robot to carry the ball machine camera to monitor the site construction, when the safety hazard occurs, the safety supervisor can receive a safety warning, and through the background can be monitored in real time. First of all, the camera ball machine collects pictures and videos of workers wearing hard hats at the construction site to build a VOC dataset, and uses labelme software to label the data set with points of interest; Then, the target dataset is trained and tested by using the YOLOv4 deep learning target recognition algorithm in Qt; Then, the on-site safety helmet wearing is monitored, and finally the on-site wearing of the safety helmet is positioned and the coordinate display is displayed, that is, the additional target test is successful, and safety behavior supervision of the construction personnel at the construction site are realized. The results show that the trained safety supervision system accurately identifies the hard hats worn by workers in the video stream of the construction site, which provides ideas and directions for the development of the new model of safety supervision.
Three-Phase Three-Level Reduced Switch Count Isolated AC/DC Neutral-Point Clamped Converter With High-Frequency DC-Link

This paper proposes a three-phase three-level reduced switch count isolated AC/DC Neutral-Point Clamped (NPC) converter, with high-frequency DC-link, for applications of unidirectional power flow. No bulky electrolytic capacitors are necessary in the DC-link, in contrast with conventional multi-level topologies. A Hybrid Sinusoidal Pulse Width Modulation (HSPWM) strategy is used to operate the proposed converter. The applied PWM technique is able to operate the AC-side converter stage with only one switch commuting in a switching period. The switches of the isolated pulsating DC/DC converter are commuted with half of the switching frequency of the AC side's converter. A dual-loop control strategy with voltage PI and current resonant PI controllers is adopted to guarantee the reference load voltage and almost sinusoidal grid currents. Simulation results are presented to validate the proposed converter operation.
Analysis and Design of LLC Based Dual Half Active Bridge Resonant Converter

In this paper, a high frequency isolated LLC based dual half active bridge resonant converter (DHABRC) is proposed. An electrolytic capacitor is often required for power conversion units which has many operational and reliability issues like short life-span, size and weight etc. The need of electrolytic filter capacitors required at input-output terminals of a DC-DC converter has been eliminated by replacing two active switches of a full bridge configuration with film capacitors. This leads to the reduction in number of switch counts of proposed DHABRC. Also, the complexity and cost of the topology will be reduced. The proposed DHABRC has been analyzed using modified fundamental harmonics approximation (FHA) to reduce the computational burden. The conditions for the soft-switching have been derived to obtain high efficiency over a wide range of load. For the verification of the proposed converter, experimental results are included for a 500 W laboratory prototype.
Design of a Quasi-Optical Launcher for 263 GHz Low Order Mode gyrotron

In this paper, a Quasi-Optical launcher operating at 263 GHz with low order TE3,2 mode is designed for THz gyrotron at Wuhan National High Magnetic Center (WHMFC). A TE3,2 to TE8,3mode converter is designed up front, because the lower-order operating mode TE3,2 does not follow the mode selection rules for Denisov-type launchers. The launcher consists of a left-handed (LH) TE3,2 to right-handed (RH) TE8,211-fold helically corrugated waveguide mode converter, a TE8,2to TE8,3azimuthally symmetric ripple-wall waveguide mode converter and a Denisov-type launcher. A coupled-wave theory MATLAB code for analysis of the electromagnetic fields at the deformed waveguide wall has been developed. The commercial simulation result shows the launcher can generate a Gaussian-like mode with a scalar correlation coefficient of 93.50% and a vector correlation coefficient of 85.65% at the launcher aperture.
Degradation Monitoring of Power Modules Based on Frequency-Domain Thermal Model

Frequency-domain thermal model has been proved to be able to provide accurate estimation of temperature of devices under multi-timescales. In this paper, the degradation of thermal grease of power modules is comprehensively investigated through FEM simulation analysis and experiment measurements. Results show the correlation between the degree of degradation and thermal parameters of frequency-domain thermal model, which can be used for degradation monitoring of power semiconductor devices.