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The indirect method for bridge modal identification based on the response of moving vehicles has attracted widespread attention in recent years. However, most existing studies only focus on the simply supported bridge, while continuous girder bridges are widely used in practical engineering. Therefore, this study proposes an indirect frequency identification method for continuous girder bridges. First, the mode shape formula of the equal-span continuous beam is deduced using the three-moment equations, and the analytical solution of the vehicle vibration response is deduced via the vehicle–bridge coupled vibration theory. Second, the derived analytical solution is verified through numerical analysis results and field test results. Finally, the effects of bridge and vehicle parameters on the frequency identification accuracy are analyzed. The results show that a reasonable frequency of the trailer should be selected to avoid the resonance between the vehicle and the bridge for better performance. The research findings can provide a reference for the indirect identification of continuous girder bridges based on the response of moving vehicles. [ABSTRACT FROM AUTHOR]

To clarify the effect of CuO on the arc erosion behavior of AgZrO 2 contact materials, the Ag-8 wt.%ZrO 2 contact materials without and with CuO addition were prepared by the combination of three-dimensional vibrating mixing and hot-pressing sintering, and the electrical contact tests were performed 5000 times on a JF04D electrical contact testing system. The effect of CuO additive on the arc erosion behavior of Ag-8 wt.%ZrO 2 contact material was studied, and the arc erosion mechanism was discussed as well. The results show that an appropriate CuO addition can significantly improve the hardness, electrical conductivity and arc erosion resistance of Ag-8 wt.%ZrO 2 contact material. At 0.5 wt%CuO, the optimal combination of relative density, hardness and electrical conductivity can be achieved, which are 99.48 %, 79.0 HV and 79.3 %IACS, respectively. Furthermore, the Ag-8 wt.%ZrO 2 contact material with 0.5 wt%CuO addition exhibits the lowest arc energy and shortest arc duration, least mass loss, and silver splashing as well as the formation of pores are also significantly inhibited, displaying excellent arc erosion resistance. This can be ascribed to the improved electrical conductivity and enhanced interface bonding together with CuO decomposition under high temperature arc. [ABSTRACT FROM AUTHOR]

The use of in vitro new approach methodologies (NAMs) to assess respiratory irritation depends on several factors, including the specifics of exposure methods and cell/tissue-based test systems. This topic was examined in the context of human health risk assessment for cleaning products at a 1-day public workshop held on 2 March 2023, organized by the American Cleaning Institute® (ACI). The goals of this workshop were to (1) review in vitro NAMs for evaluation of respiratory irritation, (2) examine different perspectives on current challenges and suggested solutions, and (3) publish a manuscript of the proceedings. Targeted sessions focused on exposure methods, in vitro cell/tissue test systems, and application to human health risk assessment. The importance of characterization of assays and development of reporting standards was noted throughout the workshop. The exposure methods session emphasized that the appropriate exposure system design depends on the purpose of the assessment. This is particularly important given the many dosimetry and technical considerations affecting relevance and translation of results to human exposure scenarios. Discussion in the in vitro cell/tissue test systems session focused on the wide variety of cell systems with varying suitability for evaluating key mechanistic steps, such as molecular initiating events (MIEs) and key events (KEs) likely present in any putative respiratory irritation adverse outcome pathway (AOP). This suggests the opportunity to further develop guidance around in vitro cell/tissue test system endpoint selection, assay design, characterization and validation, and analytics that provide information about a given assay's utility. The session on applications for human health protection emphasized using mechanistic understanding to inform the choice of test systems and integration of NAMsderived data with other data sources (e.g., physicochemical properties, exposure information, and existing in vivo data) as the basis for in vitro to in vivo extrapolation. In addition, this group noted a need to develop procedures to align NAMs-based points of departure (PODs) and uncertainty factor selection with current human health risk assessment methods, together with consideration of elements unique to in vitro data. Current approaches are described and priorities for future characterization of in vitro NAMs to assess respiratory irritation are noted. [ABSTRACT FROM AUTHOR]

As a critical component of electric vehicles, the powertrain has a significant impact on the overall performance of vehicles. In addressing the challenge of lengthy testing cycles, this study develops a para model of the powertrain, utilizing digital twin (DT) technology, thereby establishing a framework for simulation testing of multi-controller intermodulation. We establish functional definition coverage testing by designing specific functional requirement use cases, and we validate the failure mechanism via fault injection use cases. The results indicate that the DT testing platform can effectively simulate the operational interactions among various controllers within the powertrain system. In comparison to traditional field testing, the digital twin-based testing methodology offers enhanced operational efficiency and allows for the examination of testing conditions that are impractical to implement in real vehicles, particularly in the context of fault injection testing, thus facilitating the early detection of potential safety risks within the system. The advancement of this technical solution holds significant practical implications for the future mass production and development of electric vehicles. [ABSTRACT FROM AUTHOR]

This study presents the development and evaluation of a spin test rig for high-speed rotating components. The innovation of this study is using a discrete model to determine dynamic positioning during the preliminary design phase based on vibration characteristics. The primary aim is to manage vibrations and alternating stress effects from rotor dynamics to prevent issues such as crack propagation or bursts before achieving desired speeds. MATLAB 2023b Simulink-based tool was developed, which played a role in providing the design of bearing support regions and stiffness values. The system underwent rigorous validation through structural, modal, and harmonic finite element analyses. Testing showed a maximum deviation of 4.2% for 10 kg specimen and 4.85% for 4 kg specimen between Simulink predictions and actual data, due to factors such as contact and bearing damping. For the 10 kg specimen, the maximum equivalent stress was 314.92 MPa with an alternating stress of 64.87 MPa at 0.5% damping ratio, representing 37.27% of the yield limit. For the 4 kg specimen, the maximum equivalent stress was 513 MPa with alternating stress below 40 MPa at 3% damping ratio, corresponding to 54.32% of the yield limit. This research enhances the reliability and performance of high-speed rotating machinery. [ABSTRACT FROM AUTHOR]

This study reports the methodology for reconstructing anomalous temperature index series of China in 1368–1911 based on the REACHES database which digitizes the Chinese records quoted in the Compendium of Meteorological Records of China in the Last 3000 Years. The reconstruction adopts an ordinal scale index approach ranging from −2 (very cold) to 1 (warm). Based on the grading criteria, a total of 12,871 records were retrieved through a standard coding system established at REACHES. Sensitivity experiments were performed to test robustness of the index system and a reasonability test was conducted to develop an appropriate method for deriving areal mean temperature index. The reconstructed series were validated through comparison with early instrumental data from Global Historical Climatology Network which shows good correlations and reliability of the REACHES reconstructed index data. Annual and semi-annual (winter and summer) temperature index data series were released for the whole domain as well as the 3- and 15-subregion geographical domains in China. [ABSTRACT FROM AUTHOR]

Real-time hybrid test is an economical and efficient testing method to evaluate nonlinear structural performance. During the operation of real-time hybrid test, the time delay caused by the operating error of the actuator results in the worse stability and accuracy of the real-time hybrid test. To compensate for the delay of the actuator, the stability of the hybrid test system and the accuracy of the test are improved. In this paper, the advantages of the numerical integration algorithm and the linear acceleration extrapolation method are composed organically, and then a universal linear extrapolation-Newmark optimization compensation strategy is proposed to compensate for the time delay. Under the action of different seismic waves with and without the optimized compensation strategy, the self-developed DELTA-OpenSees real-time hybrid test system is used to comprehensively compare and analyze the real-time hybrid test of three-story frame structure with linear springs. The root mean square error and maximum error amplitude of the maximum error amplitude of the optimization results can reach 2.73% and 2.18%, respectively, which proves that the developed linear extrapolation-Newmark optimization compensation strategy can effectively improve the stability and accuracy of the real-time hybrid test system, and the optimization compensation strategy has good tracking performance and robustness. [ABSTRACT FROM AUTHOR]

Second‐life batteries (SLBs), which are batteries retired from electric vehicles (EVs), can be used as energy storage systems to enhance the performance of distribution networks. Two issues should be addressed particularly for the optimal sizing of SLBs. Compared with fresh batteries, the failure rate of SLBs is relatively high, and timely and preventive replacement is needed. In addition, the flexibility introduced by EVs and installed SLBs should be coordinated to achieve optimal economic benefits. This paper focuses on the efficient utilization of SLBs by highlighting reliability‐flexibility concerns in optimal sizing. The model is formulated as a bi‐level model. On the upper‐level, considering the operational reliability constraints of SLBs, decisions regarding the investment and replacement of SLBs are optimized. Distribution network operations are improved on the lowerlevel, with an effective spatiotemporal flexible dispatch strategy for EVs. Finally, a linearized process for the optimal sizing of SLBs is presented and efficiently implemented. The Sioux Falls network and IEEE 69‐node distribution network are coupled as the test system. According to the simulation results, when the state of health of the SLBs decreased to 70%, the conditions were unreliable. The differences in the optimal SLB size and costs considering reliability and flexibility are highlighted. [ABSTRACT FROM AUTHOR]

The microchannel plate (MCP) is an electron multiplier with millions of micro through-holes that must withstand strong vibrations and enormous shocks in spaceborne detectors. To ensure the reliability and robustness of the MCP in space applications, we proposed an equivalent mechanical model of the MCP to investigate its mechanical properties, since the direct creation of the finite element model using the finite element method (FEM) is not feasible. Then, we developed a test system to verify the effectiveness of the equivalent mechanical model. The results show that the error of harmonic response analysis and the test result is less than 10 %, which is acceptable. Finally, we conducted parametric studies of the MCPs and obtained the equivalent mechanical model of the MCPs with different geometric parameters. This study will help researchers to optimize the MCP for aerospace-grade detectors. [ABSTRACT FROM AUTHOR]

A disturbance in a power system causes the frequency to deviate from its nominal value. The load and generation of the system are strategically adjusted to restore the synchronous frequency. This paper introduces novel shrinking-horizon model predictive control (MPC) technique, which employs a centralized controller for managing the load-frequency of a single-area power system and distributed controllers for multi-area systems. The controller optimally changes generation settings and sheds non-critical loads to make the frequency and tie-line power deviation zero. In contrast to existing approaches that use an approximate first-order transfer function model, this paper presents a structure-preserving linear state-space model for power systems. This model takes into account frequency and voltage dependencies of both load and generation, allowing for more accurate representation of power system behavior. During rescheduling, the controller minimizes additional cost associated with changes while satisfying various operational and physical constraints. The paper conducts several case studies using IEEE test systems to devise corrective action plans for both under- and over-frequency scenarios. The proposed controller's robustness is tested against disturbances originating from renewable energy sources. Furthermore, a performance comparison is drawn between the proposed controller and existing control techniques. The comparative analysis indicates that the proposed approach consistently outperforms other controllers in terms of dynamic performance improvement, measured by parameters such as settling time, overshoot, undershoot, and error reduction. It is observed that the maximum undershoot and the settling time of the frequency is the least for centralized control. Comparative studies indicate that under different circumstances, the proposed approach outperforms other controllers in dynamic performance improvement, measured by settling time, overshoot, undershoot, and error reduction. The net rescheduling cost obtained by the proposed centralized MPC, cooperative distributed MPC, and non-cooperative distributed MPC-based controllers is 38, 25, and 24% lower than the conventional PI controller used for LFC of IEEE 39-bus system. This validates the suggested controllers' cost-effectiveness. [ABSTRACT FROM AUTHOR]

Power systems are being confronted with a number of ecological and financial difficulties, and distributed generators (DGs) will be an effective solution. However, inappropriate DGs incorporation may cause additional power stability issues and system losses. DGs that are strategically positioned could solve these issues. This study implements the multi-objective fuzzified firefly algorithm (MOFFA) to integrate optimally sized DGs with six different objective functions (OBFs) on a standard IEEE 33 bus system as well as a functional 62 bus Indian distribution system (IDS) of Tamil Nadu power sector. Three distinct scenarios of multi-objective optimization problems are addressed. In Scenario 1, the objective is to minimize power loss, bus voltage deviation, and cost simultaneously. In Scenario 2, the focus is on minimizing power loss, enhancing voltage stability index (VSI), and reducing toxic gasses outflow. Lastly, in Scenario 3, the goal is to minimize bus voltage deviation, cost, and lower average voltage total harmonic distortion THDv. The integration of DGs in the IEEE-33 bus test system resulted in remarkable improvements through the optimization process. Specifically, the power loss is reduced by approximately 65.64%, the cost decreased by about 29.58%, and the toxic discharge was lowered by approximately 66.69%. In the IDS-62 bus test system, the optimization results in a noteworthy reduction of power loss to 5.1% of the total load. These substantial reductions highlight the significant progress made, showcasing the effectiveness of the optimization process and the integration of DGs in reducing energy wastage. [ABSTRACT FROM AUTHOR]

A transmission network is an important part of the power transformers to transmit the generated energy and power to the load centers. As such, the transmission network requires significant expansion costs to alleviate congestion as well as to supply an acceptable reliability level. In this matter, transmission network expansion planning (TNEP) is known as a large-scale mathematical problem including long-term effects of the power system. In this paper, long-term effect of demand response (DR) is explored on the loading rate of the system as well as subsequent line loading influence on line failure rates. To investigate the DR effectiveness on TNEP, its cost is addressed in the objective of the proposed mixed integer nonlinear planning model. Moreover, alleviating the failure rate of old lines can decrease the construction of new lines while providing the desirable reliability of the system. Furthermore, a decrease in the loading rate of existing transmission lines provides valuable gains at the horizon year. Thus, the value of the transmission system in the objective function would increase by DR. Besides, peak clipping prevents local marginal price (LMP) inflation and smoothens the LMP profile across the system buses; so congestion surpluses will decrease. Afterward, the sensitivity analysis in the simulation part is implemented to investigate how demand response can influence on value of LMP at different nodes. Eventually, the developed model is executed on IEEE 24-bus reliability test system for three scenarios in order to assess the efficiency of the proposed approach. [ABSTRACT FROM AUTHOR]

In response to the problems of low control accuracy, single detection of operating parameters, and insufficient collaborative control of unmanned fertilization in field fertilization operations, this paper proposes an adaptive control strategy for fertilizer discharging shaft speed based on segmented linear interpolation method. By constructing a relationship model between fertilizer discharging shaft speed and motor control signals in different speed ranges, the on-site self-calibration of fertilizer discharging shaft speed and the precise control of the fertilization rate is achieved. At the same time, real-time detection and warning technology for multiple working condition parameters were integrated, and a bus communication protocol between unmanned tractors and variable-rate fertilizer applicators was developed. A variable-ratefertilization monitoring system based on unmanned tractors was developed, and actual experimental tests were conducted to test the system's performance. Among them, the calibration test results of fertilization rate showed that the discharging rate of the fertilizer apparatuses (p) was negatively correlated with the rotation speed of the fertilizer discharging shaft, and that the installation position of the fertilizer apparatuses affected the uniformity of fertilization between the rows of the fertilizer applicator. The speed response test of the fertilizer discharging shaft showed that the average response time (Ts) of the fertilizer discharging shaft speed controlled by the self-calibration model was 0.40 s, the average steady-state error (ess) was 0.13 r/min, and the average overshoot (σ) was 7.33%. Compared with the original linear model, the ess was reduced by 0.23 r/min, and the σ was reduced by 1.54 percentage points. The results of the fertilization status detection tests showed that the system can achieve real-time detection of different operating parameters and states, as well as collaborative control of tractors and fertilizer applicators. The results of the fertilization rate control accuracy test showed that the average fertilization control error of the system was 1.91% under different target fertilization rate, which meets the requirements of variable-rate fertilization field operations. This study can serve as a technical reference for the design and development of fertilization robots in the context of unmanned farm development. [ABSTRACT FROM AUTHOR]

This paper presents a new optimization technique based on the hybridization of two meta-heuristic methods, Jellyfish Search (JS) and Moth Flame Optimizer (MFO), to solve the Optimal Power Flow (OPF) problem. The JS algorithm offers good exploration capacity but lacks performance in its exploitation mechanism. To improve its efficiency, we combined it with the Moth Flame Optimizer, which has proven its ability to exploit good solutions in the search area. This hybrid algorithm combines the advantages of both algorithms. The performance and precision of the hybrid optimization approach (JS-MFO) were investigated by minimizing well-known mathematical benchmark functions and by solving the complex OPF problem. The OPF problem was solved by optimizing non-convex objective functions such as total fuel cost, total active transmission losses, total gas emission, total voltage deviation, and the voltage stability index. Two test systems, the IEEE 30-bus network and the Mauritanian RIM 27-bus transmission network, were considered for implementing the JS-MFO approach. Experimental tests of the JS, MFO, and JS-MFO algorithms on eight well-known benchmark functions, the IEEE 30-bus, and the Mauritanian RIM 27-bus system were conducted. For the IEEE 30-bus test system, the proposed hybrid approach provides a percent cost saving of 11.4028%, a percent gas emission reduction of 14.38%, and a percent loss saving of 50.60% with respect to the base case. For the RIM 27-bus system, JS-MFO achieved a loss percent saving of 50.67% and percent voltage reduction of 62.44% with reference to the base case. The simulation results using JS-MFO and obtained with the MATLAB 2009b software were compared with those of JS, MFO, and other well-known meta-heuristics cited in the literature. The comparison report proves the superiority of the JS-MFO method over JS, MFO, and other competing meta-heuristics in solving difficult OPF problems. [ABSTRACT FROM AUTHOR]

This paper addresses the critical challenge of optimizing power flow in multi-area power systems while maintaining information privacy and decentralized control. The main objective is to develop a novel decentralized stochastic recursive gradient (DSRG) method for solving the optimal power flow (OPF) problem in a fully decentralized manner. Unlike traditional centralized approaches, which require extensive data sharing and centralized control, the DSRG method ensures that each area within the power system can make independent decisions based on local information while still achieving global optimization. Numerical simulations are conducted using MATLAB (Version 24.1.0.2603908) to evaluate the performance of the DSRG method on a 3-area, 9-bus test system. The results demonstrate that the DSRG method converges significantly faster than other decentralized OPF methods, reducing the overall computation time while maintaining cost efficiency and system stability. These findings highlight the DSRG method's potential to significantly enhance the efficiency and scalability of decentralized OPF in modern power systems. [ABSTRACT FROM AUTHOR]

Intelligent voltage stability monitoring remains an essential feature of modern research into secure operations of power system networks. This research developed an adaptive neuro-fuzzy expert system (ANFIS)-based predictive model to validate the viability of two contemporary voltage stability indices (VSIs) for intelligent voltage stability monitoring, especially at intricate loading and operation points close to voltage collapse. The Novel Line Stability Index (NLSI) and Critical Boundary Index are VSIs deployed extensively for steady-state voltage stability analysis, and thus, they are selected for the predictive model implementation. Six essential power system operational parameters with data values calculated at varying real and reactive loading levels are input features for ANFIS model implementation. The model's performance is evaluated using reliable statistical error performance analysis in percentages ( M A P E and R R M S E p ) and regression analysis based on Pearson's correlation coefficient (R). The IEEE 14-bus and IEEE 118-bus test systems were used to evaluate the prediction model over various network sizes and complexities and at varying clustering radii. The percentage error analysis reveals that the ANFIS predictive model performed well with both VSIs, with CBI performing comparatively better based on the comparative values of M A P E , R R M S E p , and R at multiple simulation runs and clustering radii. Remarkably, CBI showed credible potential as a reliable voltage stability indicator that can be adopted for real-time monitoring, particularly at loading levels near the point of voltage instability. [ABSTRACT FROM AUTHOR]

Robotic grasping is a common operation scenario in industry and agriculture, in which the force sensing function is a significant factor to achieve reliable grasping. Existing force sensing methods of flexible grippers require intelligent materials or force sensors embedded in the flexible gripper, which causes such problems of higher manufacturing requirements and contact surface properties changing. In this paper, a novel rope-driven force sensing flexible gripper is designed based on the fin-shaped gripper structure, which can realize the grasping sensing functions of contact nodes and contact forces without the need for force sensors. Firstly, the rope-driven force sensing flexible gripper is designed, including the driving unit, the transmission part, the gripper unit, and the force sensing unit. The force sensing unit and the gripper unit are connected by rope, and the prototype of the rope-driven force sensing flexible gripper is completed. Secondly, a force sensing algorithm and control system based on finite element method and grasping geometric relationship are designed to realize the rope-driven force sensing flexible gripper grasping control and sensor data acquisition and processing. Finally, the experimental system of the rope-driven force sensing flexible gripper is built, and the grasping experimental tests of objects with different diameters and different contact nodes are carried out to verify the force sensing function of the rope-driven force sensing flexible gripper. The force sensing flexible gripper designed in this paper can provide a new idea for the design and force sensing method of intelligent robotic grasping system in robotic teaching, scientific research, and industrial applications. [ABSTRACT FROM AUTHOR]

Background: Rotary Ni-Ti files are susceptible to sudden intra-canal separation due to cyclic fatigue stress, particularly in curved canals. To increase resistance to cyclic fatigue, new heat-treated files have been introduced. This study aimed to compare the performance of four heat-treated Ni-Ti files in two simulated curved root canals by evaluating the effect of the alloy, rotation speed, and diameter of the files on their resistance to cyclic fatigue. Methods: The Ni-Ti files included in the study were the ProTaper Gold® (Dentsply Sirona) F2, ProTaper Ultimate® (Dentsply Sirona) F2, FQ® (Komet) 25.06, and Blueshaper® (Zarc4Endo) Z4 25.06. Two groups of 30 files were selected for each system and were tested in two simulated canals milled in a specific metal template. One group was tested in a 60° curved canal and the other in a 90° curved canal. Results: In the 60° simulated canal, there were no instrument fractures within the 15 min time limit. In the 90° simulated canal, the Blueshaper Z4 demonstrated a lower resistance to cyclic fatigue, while FQ 25.06 showed statistically higher fatigue resistance based on both the Kruskal–Wallis and Games–Howell tests (p < 0.05). Conclusions: No differences were found between files when tested in a 60° curved canal for up to 15 min. However, in a 90° canal, the FQ® files showed significantly higher resistance to cyclic fatigue, especially compared to the Blueshaper® Z4. The ProTaper Ultimate and ProTaper Gold produced intermediate results, with the ProTaper Ultimate F2 slightly outperforming the ProTaper Gold F2. [ABSTRACT FROM AUTHOR]

In a deregulated power system, managing congestion is crucial for effective operation and control. The goal of congestion management is to alleviate transmission line congestion while adhering to system constraints at minimal cost. This research proposes a hybrid Harris Hawk Optimization–Sine Cosine Algorithm (hHHO-SCA) for an efficient generation rescheduling approach to achieve the lowest possible congestion cost. The hybridization has been performed by introducing the features of SCA in the HHO to boost the exploration and exploitation steps of HHO, providing an efficient global solution and effectively optimizing rescheduled power output. The effectiveness of this methodology is evaluated using IEEE 30 and IEEE 118-bus test systems, taking into account system parameters. The potency of the proposed method is analyzed by comparing the results of the hHHO-SCA with those from other recent optimization techniques. The findings show that the hHHO-SCA outperforms other methods by avoiding local optima and demonstrating promising convergence characteristics. [ABSTRACT FROM AUTHOR]

Automated testing of GUI elements on electronic screens by machine vision is widely used in smart manufacturing production lines. However, in the complex environment of factories, interference factors such as light reflection, platform vibration, and placement angle make it difficult for testing robots to recognize and locate GUI elements on the equipment's screen to be tested. In addition, the recognition algorithms based on screen GUI elements currently have problems such as slow detection speed and large model size, which limit the deployment of detection models on test robots. To address these problems, this paper proposes a lightweight model that can overcome the interference of the factory environment based on the YOLOv5 algorithm for recognizing GUI elements. First, a reinforced position and channel attention module (PCA) is proposed to enhance the extraction and fusion ability of weak feature elements affected by interference; then, a three-way feature pyramid network (TWFPN) module is constructed at the intermediate feature layer of the neck structure to provide more accurate localization information. Meanwhile, the loss function of the original algorithm is replaced with SIoU to improve the convergence speed. Finally, a lightweight structure combining the Ghost module and PConv is introduced into the model to reduce the model parameters and improve the detection speed. The method was evaluated on the constructed feature-enhanced GUI (FE_GUI) dataset. The final model shows a 2.7% improvement in average accuracy (mAP@0.5), a 30% reduction in model weight, and an increase in detection speed to 85 FPS compared to the original YOLOv5. The results demonstrate that the method solves the issues of element recognition and model deployment for a vision test system and surpasses existing models in terms of recognition accuracy and detection speed. [ABSTRACT FROM AUTHOR]

Due to the lack of essential understanding of asphalt foaming behavior, engineering problems such as mix design failure and unstable performance of foamed asphalt cold recycling mixtures are prone to occur. This paper develops a novel asphalt foaming performance testing system and proposes new indicators to evaluate the effectiveness of asphalt foaming. The 3D spatial coordinates of different points on the foamed asphalt surface and the height of the foamed asphalt corresponding to these coordinates can be continuously monitored by binocular ranging equipment. By analyzing these dynamic parameters, the application effect of binocular ranging technology, the expansion characteristics and dynamic evolution rules of foamed asphalt in the spatial domain are analyzed. Results showed that by a combined use of the designed binocular ranging system and new evaluation indicators, the foaming ability and post-foaming stability of asphalt can be accurately assessed by comprehensively reflecting the expansion characteristics of foamed asphalt. To achieve a more efficient mix design of foamed asphalt cold recycling mixture, the correlation between asphalt foaming indicators and the road performance of the mixture could be an important focus of the next stage. [ABSTRACT FROM AUTHOR]

In microgrids, voltage imbalance control is crucial to preserving the required level of power quality. The article presents a tracker design that mitigates the unbalance in the microgrids. The proposed microgrid model includes positive and negative sequences, whereby the positive sequences are controlled, and the negative sequence is treated as an external disturbance (whose effect must be attenuated). The uncertainty in the external disturbance is modelled in the norm-bounded form. The suggested control is based on attracting (driving) the state trajectory into a small region, including the origin (attracting ellipsoid-set). The effect of the negative sequence components is attenuated by minimizing the ellipsoid volume. When the state trajectory enters that region, it will never leave it for the future time (termed invariant-set). Two theorems were formulated for tracker synthesis that follows the desired reference and reduces the negative sequence impact. These theorems are the invariant-set method and the H ∞ approach. The validity of the suggested control is demonstrated via testing the system under various operational unbalanced scenarios, such as unbalances or faults at the load side or in the transmission lines. The simulations show the superiority of the suggested method in terms of accuracy and dynamic response when compared with the H∞. Additionally, a comparison is made between the suggested tracker and Active Disturbance Rejection Control (ADRC). • Microgrid model with positive and negative sequences is presented. • Negative sequence is treated as an uncertain disturbance. • Two developed new theorems handle this disturbance in tracker design. • A positive-sequence tracker using invariant-sets is proposed for efficient disturbance rejection. • Performance is compared to H¥ and ADRC under various operational conditions. [ABSTRACT FROM AUTHOR]

The article proposes a new model for defining and implementing performance tests used in the process of designing and operating IT systems. By defining the objectives, types, topological patterns, and methods of implementation, a coherent description of the test preparation and execution is achieved, facilitating the interpretation of results and enabling straightforward replication of test scenarios. The model was used to develop and implement performance tests in a laboratory environment and in a production system. The proposed division of the testing process into layers correlated with the test preparation steps allows to separate quasi-independent areas, which can be handled by isolated teams of engineers. Such an approach allows to accelerate the process of implementation of performance tests and may affect the optimization of the cost of their implementation. [ABSTRACT FROM AUTHOR]

To investigate the nonlinear flutter characteristics of long-span suspension bridges under different deck ancillary structures and configurations, including those with and without a central wind-permeable zone, as well as to analyze the hysteresis phenomenon of a subcritical flutter and elucidate the mechanisms leading to the occurrence of nonlinear flutter, this paper studies first the post-flutter characteristics of the torsion single-degree-of-freedom (SDOF) test systems and vertical bending–torsion two-degree-of-freedom (2DOF) test systems under different aerodynamic shape conditions are further analyzed, and the role of the vertical vibration in coupled nonlinear flutter is discussed. The results indicate that better flutter performance is achieved in the absence of bridge deck auxiliary structures with a central wind-permeable zone. The participation of vertical vibrations in the post-flutter vibration increases with the increase in wind speed, reducing the flutter performance of the main girder. Furthermore, the hysteresis phenomenon in the subcritical flutter state is observed in the wind tunnel experiment, and its evolution law and mechanism are discussed from the perspective of amplitude-dependent damping. Finally, the vibration-generating mechanism of the limit oscillation ring is elaborated in terms of the evolution law of the post-flutter vibration damping. [ABSTRACT FROM AUTHOR]

Oscillating fins are devices designed to produce thrust through periodic undulating movements. However, these structures lack flexibility and often provide thrust in only one fixed direction. Observation and biological references suggest that the dorsal fin rays of seahorses can tilt longitudinally in the spine direction, changing the thrust direction. This study aims to analyze the dynamic effects of seahorse dorsal fin inclining and design a flexible bionic thruster based on this principle. Computational fluid dynamics analysis hypothesizes that fin inclination controls the net force direction in the vertical plane. A force sensor and pulley system test platform were constructed to examine the influences of wave features and the inclination angle on thrust in both vertical and horizontal directions, with discrete fin surfaces used to eliminate force interference. Force testing and snapshots indicate that wave velocity positively impacts net force magnitude, while fin inclination allows for control over force orientation. This tiltable oscillating fin thruster possesses more degrees of freedom, leading to better flexibility and providing controllable thrust orientation. [ABSTRACT FROM AUTHOR]

Fentanyl and its analogues are synthetic opioids of varying potencies that are unfortunately heavily abused. Over the last 15 years, fentanyl and its analogues have contributed to the increasing prominence of hospitalisation and numerous deaths due to drug overdose. In this comprehensive literature review, the mechanism of toxicity of the drug in humans is evaluated. A systematic approach was used whereby the relevant literature has been detailed where the toxicity of fentanyl and/or its analogues to different organs/systems were investigated. Furthermore, the review covers the post-mortem toxicological data and demographic information from past fatal cases where fentanyl was believed to be involved. Such insight into fentanyl toxicity is useful as an aid to better understand the toxic doses of the drug and the suspected mechanism of action and the unexpected complications associated with overdose incidences involving the drug. Finally, the review offers an overview of the traditional and emerging test systems used to investigate the adverse effects of fentanyl on human health. [ABSTRACT FROM AUTHOR]

As the penetration of renewable energy sources (RESs), particularly wind power, continues to rise, the uncertainty in power systems increases. This challenges traditional optimal power flow (OPF) methods. This paper proposes a Calibrated Safety Constraints Optimal Power Flow (CSCOPF) model that uses the Improved Acceleration Coefficient-Based Bee Swarm algorithm (IACBS) in combination with the equivalent current injection (ECI) model. The proposed method addresses key challenges in wind-integrated power systems by ensuring preventive safety scheduling and enabling effective power incident safety analysis (PISA). This improves system reliability and stability. This method incorporates mixed-integer programming, with continuous and discrete variables representing power outputs and control mechanisms. Detailed numerical simulations were conducted on the IEEE 30-bus test system, and the feasibility of the proposed method was further validated on the IEEE 118-bus test system. The results show that the IACBS algorithm outperforms the existing methods in both computational efficiency and robustness. It achieves lower generation costs and faster convergence times. Additionally, the CSCOPF model effectively prevents power grid disruptions during critical incidents, ensuring that wind farms remain operational within predefined safety limits, even in fault scenarios. These findings suggest that the CSCOPF model provides a reliable solution for optimizing power flow in renewable energy-integrated systems, significantly contributing to grid stability and operational safety. [ABSTRACT FROM AUTHOR]

The article discusses the problem of adaptive system synthesis to provide the detection, estimation, and elimination of the negative consequences of faults in the thrusters of underwater robots and deviations of their parameters. For this purpose, an approach consisting of three stages is proposed. At the first stage, based on a bank of diagnostic observers, deviations of the thruster parameters from their nominal values or the occurrence of errors in the readings of its sensors are detected. At the second stage, the magnitudes of the detected deviations and errors are estimated using sliding mode observers. To estimate not only single but also multiple faults, the additional sliding mode observers are used. At the third stage, a control signal is generated to retain the basic dynamic properties of the thruster based on the estimated magnitudes of deviations and errors. Thus, the main contribution of this paper is designing the systems compensating for the consequences of faults occurring in the thrusters of the UR and errors in the readings of the angular velocity sensors. This avoids reducing the accuracy of movement along specified trajectories, as well as preventing accidents that could lead to the loss of the vehicle. The operability and efficiency of the proposed systems were tested using computer simulations and experimental studies on an electro-mechanical stand. [ABSTRACT FROM AUTHOR]

Due to the effects of swing motion, the performances and internal flow characteristics of marine centrifugal pump undergo some unsteady variations in the marine environment. The hydraulic test system with six degree of freedom parallel motion platform is established to study the pump performance characteristics at the different heel angles of steady roll position and pitch position. The pump head gradually decreases as heel angle increases. The pump head has decreased by 7% to reach the minimum at the 15° heel angle of roll position. At the same heel angle, the head at the roll position is lower than that at the pitch position under the rated flow condition. The fluid in the impeller passage is subjected to the additional inertial force of roll motion or pitch motion under unsteady swing motion, inducing some flow bias phenomena in the velocity field. The unsteady development of flow velocity induces the intense vortex motion, and the shedding and dissipation of interblade vortices are affected. The periodic flow-induced pulsation characteristics obviously appear in the impeller passage. The pulsation periodicity and pressure amplitude are influenced due to the swing motion. The pitch motion induces the greater hydraulic excitation and fluid-induced vibration amplitude. In addition to the pressure pulsation at the low frequencies, the pulsation amplitude at 20 times the shaft frequency is evident under pitch motion. [ABSTRACT FROM AUTHOR]

Robotic systems are crucial in modern manufacturing. Complex assembly tasks require the collaboration of multiple robots. Their orchestration is challenging due to tight tolerances and precision requirements. In this work, we set up two Franka Panda robots performing a peg-in-hole insertion task of 1 mm clearance. We structure the control system hierarchically, planning the robots' feedback-based trajectories with a central policy trained with reinforcement learning. These trajectories are executed by a low-level impedance controller on each robot. To enhance training convergence, we use reverse curriculum learning, novel for such a two-armed control task, iteratively structured with a minimum requirements and fine-tuning phase. We incorporate domain randomization, varying initial joint configurations of the task for generalization of the applicability. After training, we test the system in a simulation, discovering the impact of curriculum parameters on the emerging process time and its variance. Finally, we transfer the trained model to the real-world, resulting in a small decrease in task duration. Comparing our approach to classical path planning and control shows a decrease in process time, but higher robustness towards calibration errors. [ABSTRACT FROM AUTHOR]

To investigate the influencing factors and intrinsic relationships between potato impact force and impact damage during potato soil separation, a testing system for potato impact force was established. The impact force test system is composed of a base, a height adjustment device, a simple separation screen, a soil storage tank, an impact force sensor, and so on. By allowing potatoes to fall freely to simulate the collision process, impact force data are collected, and a high-speed camera is used to locate the impact position and analyze the degree of damage. Through the response surface analysis method, the influencing factors and laws of the impact force and impact damage during the collision process between potatoes and rods under soil and no-soil conditions were studied. The results of the response surface analysis indicate that when the screen inclination is within the range of 14.12° to 14.77°, falling height ranges from 453.83 mm to 500 mm, screen rod spacing falls within 36.50 mm to 40 mm, and the screen rod material is rubber. Potatoes can still be at a relatively low damage level when enduring a large impact force. This study has significant implications for reducing potato impact damage during harvesting, enhancing economic benefits in the potato industry, and advancing the technical level of potato harvesting equipment. In the future, based on the results of this study, further exploration can be made to optimize the design of potato harvesting equipment so as to better reduce the damage to potatoes during harvesting and subsequent processing processes and promote the sustainable development of the potato industry. [ABSTRACT FROM AUTHOR]

This study investigates the feasibility of employing an in-house-developed physical phantom dedicated to the weekly quality control testing of radiographic systems, performed by radiographers. For this purpose, a 3D phantom was fabricated, featuring test objects, including a model representing a lesion. Alongside this phantom, a commercial phantom, specifically, IBA's Primus L, was utilized. Weekly imaging of both phantoms was conducted over a span of four weeks, involving different imaging protocols and anode voltages. Subsequently, the obtained data underwent visual evaluation, as well as measurement of the intensity of selected regions of interest. The average values for three incident kilovoltages remained consistently stable over the four weeks, with the exception of the "low energy" case, which exhibited variability during the first week of measurements. Following experiments in "Week 1", the X-Ray unit was identified as malfunctioning and underwent necessary repairs. The in-house-developed phantom demonstrated its utility in assessing the performance of the X-Ray system. [ABSTRACT FROM AUTHOR]

A projection lens with a 30-degree field of view is developed for use in augmented reality (AR) glasses, including a waveguide combiner designed for a 0.35-inch LCoS panel. The entrance pupil diameter of the lens is 14 mm and the lens has an effective focal length of 16.443 mm; an F-number of 1.175. This paper has four key issues: optical projection lens design, lens manufacturing and assembly tolerance analysis, projection lens resolution testing, and AR glasses system resolution testing of panel images projected by the projection lens. After lens manufacture, the lens was tested, achieving a central field image quality of 57 cycles/mm, an angular resolution of 33 pixels per degree (PPD), a 0.7 field image quality of 40.3 cycles/mm, and an angular resolution of 23 pixels per degree (PPD). Imaging performance testing based on a diffraction-type waveguide shows a resolution of 57 cycles/mm in the center area and an angular resolution of 33 PPD. [ABSTRACT FROM AUTHOR]

Based on Terzaghi-Rendulic's axisymmetric consolidation theory, a radial consolidation coefficient calculation method is proposed, and a calculation formula is provided, followed by experimental verification. Firstly, the calculation formula of the radial consolidation coefficient was derived based on the relationship between radial consolidation degree and time factor. Then, using the GDS consolidation test system, radial drainage consolidation tests under different consolidation pressures were conducted, and displacement-time curves were obtained. Finally, the calculation method proposed in this paper was used to calculate the radial consolidation coefficient under various consolidation pressures, and the theoretical solutions were compared with experimental data. The results indicate that the computational method proposed in this paper is feasible and can accurately predict the time-dependent displacement of samples undergoing radial drainage consolidation. [ABSTRACT FROM AUTHOR]

This paper presents an extra-high voltage synthetic test system that consists of 500 kV and 765 kV voltage levels, specifically designed for transmission expansion planning (TEP) studies. The test network includes long transmission lines whose series impedance and shunt admittance are calculated using the equivalent π circuit model, accurately reflecting the distributed nature of the line parameters. The proposed test system offers technically feasible steady-state operation under normal and all single contingency conditions. By incorporating accurate modeling for long transmission lines and EHV voltage levels, the test system provides a realistic platform for validating models and theories prior to their application in actual power systems. It supports testing new algorithms, control strategies, and grid management techniques, aids in transmission expansion planning and investment decisions, and facilitates comprehensive grid evaluations. Moreover, a TEP study is conducted on this test system and various scenarios are evaluated and compared economically. [ABSTRACT FROM AUTHOR]

Featured Application: Results of tests of safety systems for work at height during the installation of formwork systems. The tests used real formwork systems and climber protection systems. Work related to the installation of formwork and the pouring of concrete involves the need to move on the formwork walls. There is a high risk of falling off the wall and falling during work. It is therefore necessary to use systems that allow for safe work at heights, but also the safety of the formwork systems themselves. This article presents the results of tests under real conditions of a person falling from the formwork. Two safety systems were tested: one based on a pole–rope system with a flexible joint and one based on climbing arrester hooks. The test results showed that the additional forces occurring in the system do not exceed 6.4 kN and that the stresses reach the highest value only at the site of installation of the system and do not exceed the yield strength of the steel used in the formwork structure. The results obtained indicate that during a fall, the fall energy is absorbed so much that there is no damage to the formwork elements, and the highest effort is observed for the formwork arrester hook and reaches 87% of the structure effort. In the case of systems with flexible posts, the maximum load values do not exceed 30% of the structure. The presented results may be useful in designing and planning assembly works and using formwork systems in concrete pouring conditions. [ABSTRACT FROM AUTHOR]

This paper proposes a high-precision interventional pressure measurement catheter with a compact structure for in vivo pressure monitoring. This catheter uses a minimally invasive testing method, and the proposed compact structure reduces pressure loss caused by fluid movement inside the catheter, ensuring accuracy in dynamically varying pressure measurements. The paper conducts a theoretical analysis of the pressure transmission process inside the catheter, fabricates a prototype, and establishes both dynamic and static pressure testing systems. Through experimental research on the effects of the catheter's dimensions on the accuracy of dynamically varying pressure measurements, it demonstrates that the compact pressure measurement catheter can effectively enhance the precision of dynamically varying pressure measurements. The catheter offers high precision, small size, and simple manufacturing processes. It holds promising applications in fields such as in-body pressure measurement and microfluidic system monitoring. [ABSTRACT FROM AUTHOR]

Background: Understanding the diverse acute effects elicited by physiotherapists in soccer players may be pertinent for enhancing performance and aiding in the mitigation of injury risk. Methods: Fifty regional-level soccer players aged 13 to 15 took part in a randomized double-blind trial. They were allocated randomly to either receive diagonal manual mobilization (DM) treatment or undergo a Nordic hamstring curl (NHC) intervention, designated as the control group. Evaluations were carried out before and after the interventions to gauge standing knee extensors (KE) and knee flexors (KF) strength using the ForceFrame Strength Testing System. The recorded variables encompassed average, maximal force, and maximal impulse for both KE and KF. Results: Following the intervention, evaluations showed no significant differences between groups in KF maximal force (F1,48 = 1.238; p = 0.271; η p 2 = 0.025), KF average force (F1,48 = 0.957; p = 0.333; η p 2 = 0.020), KF maximal impulse (F1,48 = 0.246; p = 0.622; η p 2 = 0.005), KE maximal force (F1,48 = 1.514; p = 0.225; η p 2 = 0.031), KE average force (F1,48 = 0.118; p = 0.733; η p 2 = 0.002), and KE maximal impulse (F1,48 = 2.540; p = 0.118; η p 2 = 0.050). Analysis within the DM group showed significant differences in KF maximal force (24.2 N; p = 0.004), KF average force (23.4 N; p = 0.001), KE maximal force (25.8 N; p = 0.005), KE average force (20.0 N; p = 0.044), and KE maximal impulse (265.9 Ns; p = 0.027), although no significant differences were found in KF maximal impulse (150.1 Ns; p = 0.058). Conclusions: This study indicates that both DM and NHC elicit similar effects on acute responses in KE and KF strength following intervention, although DM shows more favorable adaptations within the group. Perhaps DM could serve as a suitable warm-up strategy in specific circumstances, immediately influencing readiness for strength activities. [ABSTRACT FROM AUTHOR]

Background: Previous studies have suggested that the Pro-Kin visual feedback balance system can promote the recovery of balance function in stroke patients. Objectives: However, this system has not been used effectively in the early stages of stroke rehabilitation. This study aimed to investigate the effect of Pro-Kin system combined with weight loss system for the early recovery of balance and walking ability following a stroke. Methods: A total of 62 patients who underwent radiological diagnosis of stroke were randomly divided into two groups: a control group (n = 31) and a treatment group (n = 31). Both groups received conventional balance training. The treatment group also received training on the Pro-Kin system in conjunction with a weight loss system. Balance was measured using the Berg Balance Scale (BBS), Timed 'Up & Go' (TUG) test and Pro-Kin system. Walking ability was assessed using the Functional Ambulation Classification (FAC). The tests were performed before the start of treatment and on the 4th week following the training. There was no statistically significant difference between the groups before training. Results: After 4 weeks of training in both groups, there were significant improvements in balance and walking ability. BBS values and FAC were significantly higher (p < 0.01), TUG times, ellipse area and motion trajectory length were significantly reduced (p < 0.01, p < 0.05) after training. The treatment group outperformed the control group (p < 0.05). In addition, there was a positive correlation between balance function and walking ability (p < 0.01). Conclusion: The Pro-Kin system combined with weight loss system is a viable method that promotes early reconstruction of balance and walking ability following a stroke. Trial registration: Clinical trial number ChiCTR1900026370. https://www.chictr.org.cn/showprojEN.html?proj=43736 [ABSTRACT FROM AUTHOR]

In various domains, virtual reality (VR) has emerged as a valuable tool for simulating specific scenarios and facilitating training within controlled and secure conditions. As peripheral vision plays a crucial role in numerous contexts, it must be duly considered in VR simulations. However, while peripheral vision was examined in VR, comparisons between VR and the real world (RW) are rarely made. Therefore, this study is aimed at comparing RW and VR reaction times (RTs) to peripheral visual stimuli and the field of view (FOV). This comparison is achieved using the peripheral perception‐R (PP‐R) of the Vienna Test System and a programmed virtual replica. The virtual replica underwent additional testing, revealing good reliability for RTs but only moderate to poor for measurements of the participant's FOV. The comparison between the two environments indicates slower RTs to peripheral visual stimuli in VR than in RW. This observed discrepancy is consistent with the results of previous studies investigating RTs to foveal stimuli and can be partially explained by the latencies in the hardware and software configurations used. Nevertheless, the observed correlations between the RTs in both conditions suggest comparable visual processing within the peripheral visual field and affirm the decent replication of the real PP‐R in VR. Overall, the study's results support the usage of VR as a tool for practicing and examining specific scenarios, including peripheral vision. The discrepancies revealed in the RTs between VR and RW emphasize the need to continue examining hardware and software components in VR research. [ABSTRACT FROM AUTHOR]

This article conducts experimental research on the influencing factors of the anti-skid performance testing system SCRIM for asphalt pavement. Studied the distribution pattern of anti-skid performance test results of the testing system under different testing speeds, test tires, temperature, water film thickness, test wheel position, tire wear degree, and other factors. Revealed the influence law of various influencing factors on the anti-skid performance of asphalt pavement. The test results indicate that the SFC test value decreases with the increase of vehicle speed. The test results of tires made of different materials vary greatly, and tires with wear exceeding 3 mm cannot be used for testing. The influence of water film thickness on the measured values varies depending on the SFC level. The SFC measurement value of the normal trajectory of the vehicle's driving wheel track is the smallest, and the measurement value of the left trajectory is greater than that of the right trajectory. The SFC measurement decreases as the tire wear increases. [ABSTRACT FROM AUTHOR]

Bifurcation analysis is an essential tool in nonlinear dynamics. Bifurcation diagrams help to discover subtle features of investigated dynamics such as chaotic and periodic regimes, hidden attractors and fixed points. However, plotting high-resolution bifurcation diagrams can be a computationally challenging task, especially in multiparametric evaluation. It should be noted that the bifurcation analysis is a task with natural parallelism and thus can be efficiently solved using hybrid central-graphics processing architectures. In this paper, we propose an advanced algorithm and special software for plotting bifurcation diagrams using calculations accelerated by graphics processing unit in combination with a highly efficient semi-implicit ordinary differential equation solver. Time series processing is based on the extraction of amplitude and phase features for the density-based spatial clustering of applications with noise to determine oscillation periodicity. We showcase the features of the application of proposed solutions on a set of test chaotic systems. The performance of the analysis algorithms is investigated in comparison with conventional solutions based on central processing unit and several approaches known from the literature. We explicitly show that the proposed algorithm outperforms known solutions in both calculation speed and precision. [ABSTRACT FROM AUTHOR]

Featured Application: The multichannel luminaire systems allow a perfect color rendering of art pieces, while preserving them against light photodegradation. The presented lighting system can be applied in architectural heritage and museums. The appropriate preservation and color rendering of paintings and art pieces are a pending subject in architectural heritage, since, in most of the cases, lighting systems are not really focused on the conservation and suitable perception of these heritage resources, due to the limitations of standard LED lamps and lighting configurations. In this context, a multichannel luminaire system is proposed in the case study of the Cathedral of Seville, providing a variable and rich spectral distribution, which allows an excellent color perception linked to the daylight conditions, while the short-wavelength light is minimized in order to reduce photodegradation. Two scenarios are addressed: Museum of the Cathedral and Evangelist Chapel. The multichannel luminaire system is tested by means of subjective surveys and objective procedures (Farnswoth-Munsell and Natural Color System tests). The results show that the proposed spectral distribution of the multichannel system provides a better color discrimination in comparison with typical lighting systems, as well as a better preservation, defining a suitable lighting technology for architectural heritage. The novelty of this study lies in the multi-parameter approach, taking care of color rendering while photodegradation is minimized. [ABSTRACT FROM AUTHOR]

As automatic test technology advances, the number of programmable instruments in a single test system increases. Traditional wired communication methods have a limited range and involve complex cable layouts. Single-function wireless converters provide a viable alternative, but they have limitations. These include complicated configuration, issues with multi-system collaboration, and data blocking. This paper proposes a wireless ad hoc network platform for multi-bus instruments based on a low-cost ESP-12H WiFi module. The platform supports GPIB, RS232, RS485, and CAN bus interface instrument access. It features easy configuration, ad hoc networking, and self-repairing capabilities. A relay multi-hop network with a tree topology expands capacity and coverage. Additionally, a dynamic window-receiving mode and an improved multi-priority queue ensure data transmission integrity. The experimental results show that the platform's networking time is less than 10 s, and the coverage range reaches 50 m in complex indoor environments. It also shows good stability when running for a long time. However, due to hardware and software design limitations, the actual upload speeds fall short of the theoretical values. For example, RS232 and RS485 are about 10% slower than the theoretical values, and GPIB is about 80% slower. Further optimization is required in the future. [ABSTRACT FROM AUTHOR]

Crystalline materials have atomic-scale fluctuations in their chemical composition that modulate various mesoscale properties. Establishing chemistry–microstructure relationships in such materials requires proper characterization of these chemical fluctuations. Yet, current characterization approaches (e.g., Warren–Cowley parameters) make only partial use of the complete chemical and structural information contained in local chemical motifs. Here we introduce a framework based on E(3)-equivariant graph neural networks that is capable of completely identifying chemical motifs in arbitrary crystalline structures with any number of chemical elements. This approach naturally leads to a proper information-theoretic measure for quantifying chemical short-range order (SRO) in chemically complex materials and a reduced representation of the chemical motif space. Our framework enables the correlation of any per-atom property with their corresponding local chemical motif, thereby enabling the exploration of structure–property relationships in chemically complex materials. Using the MoTaNbTi high-entropy alloy as a test system, we demonstrate the versatility of this approach by evaluating the lattice strain associated with each chemical motif, and computing the temperature dependence of chemical-fluctuations length scale. [ABSTRACT FROM AUTHOR]

Introduction: In response to the issues of complexity and low efficiency in line loss calculations for actual distribution networks, this paper proposes a fast power flow calculation method for distribution networks based on Neo4j graph models and a hierarchical forward-backward sweep parallel algorithm. Methods: Firstly, Neo4j is used to describe the distribution network structure as a simple graph model composed of nodes and edges. Secondly, a hierarchical forward-backward sweep method is adopted to perform power flow calculations on the graph model network. Finally, during the computation of distribution network subgraphs, the method is combined with the Bulk Synchronous Parallel (BSP) computing model to quickly complete the line loss analysis. Results and Discussion: Results from the IEEE 33-node test system demonstrate that the proposed method can calculate network losses quickly and accurately, with a computation time of only 0.175s, which is lower than the MySQL and Neo4j graph methods that do not consider hierarchical parallel computing. [ABSTRACT FROM AUTHOR]

Global urbanization requires more stable and sustainable wastewater treatment to reduce the burden on the water environment. To address the problem of substrate inhibition of microorganisms during wastewater treatment, which leads to unstable wastewater discharge, this study proposes an approach to enhance the tolerance of bacterial community by artificially setting up a non-lethal high substrate environment. And the feasibility of this approach was explored by taking the inhibition of anammox process by nitrite as an example. It was shown that the non-lethal high substrate environment could enhance the nitrite tolerance of anammox bacterial community, as the specific anammox activity increasing up to 24.71 times at high nitrite concentrations. Moreover, the system composed of anammox bacterial community with high nitrite tolerance also showed greater resistance (two-fold) in response to nitrite shock. The antifragility of the system was enhanced without affecting the operation of the main reactor, and the non-lethal high nitrite environment changed the dominant anammox genera to Candidatus Jettenia. This approach to enhance tolerance of bacterial community in a non-lethal high substrate environment not only allows the anammox system to operate stably, but also promises to be a potential strategy for achieving stable biological wastewater treatment processes to comply with standards. To address substrate inhibition in wastewater treatment, the authors propose a non-lethal high substrate environment to enhance microbial community resistance. Testing this on anammox systems, they find increased nitrite tolerance and stability, with a shift to the dominant genus Candidatus Jettenia. [ABSTRACT FROM AUTHOR]

The power factor correction converter is the function of the front-end converter, followed by the DC–DC converter of the electric vehicle charger. It improves the power factor and regulates the output voltage and current. This research article proposes the Golden Eagle optimization for fractional order PI (FOPI) controller for Single Ended Primary Inductor Converter (SEPIC) power factor correction. The Golden eagle optimization is based on its knowledge of hunting tactics at various degrees of spiral trajectories to catch the prey. The FOPI controller has a broad range of controller parameters that provide better control and performance of the converter. The tuning of the parameters of the FOPI controller is optimized in Golden Eagle Optimization, and the Integral Absolute error with Integral Square error is used for the objective function. The optimized parameters of FOPI compare with the conventional PI controller performance. The SEPIC converter is designed and derived from the state space model by state space averaging, and the reduced model is obtained through the moment matching method. This system is tested under MATLAB/SIMULINK, and simulation results show improved settling time, fast dynamic response, reduction of inrush current, less harmonic distortion, and stability. [ABSTRACT FROM AUTHOR]

In this paper, an inertial amplifier and a quasi-zero stiffness system are combined to propose an energy harvesting system that can change the dynamic mass of the system. By adjusting the inertial amplifier, it is possible to change the distribution of its chaotic region and the effective range of energy collection. The kinetic equations of the system with an inertial amplifier under a combination of multiple harmonic excitations are developed. Based on this, the system was simulated and tested and the Lyapunov exponent, the RMS value of the induced voltage and the coexisting basins of attraction were plotted. Subsequently, the best optimization solution to improve the energy harvesting efficiency of the system was identified. In addition, the system was tested for impulse excitation based on the given coexisting basins of attraction. The simulation results show that the inertial amplifier can effectively improve the range of the energy harvesting region and the distribution of the chaotic region in the system ground under ultra-low-frequency vibration. The initiation of impulse excitation can change the energy harvesting performance of the system to a great extent. [ABSTRACT FROM AUTHOR]

Fault fracture zones are rock formations commonly encountered in submarine tunnels, and the diffusion mechanism of slurry in fault fracture zones has a crucial impact on submarine tunnel reinforcement. Based on the seepage equation of Bingham fluid, the tortuosity parameter, fractal theory, and variable viscosity equation are introduced to establish a spherical permeation grouting model of Bingham fluid considering the slurry diffusion path and viscosity time variability. The viscosity variation law with time of sulfur aluminate cement slurry under different seawater admixture conditions was tested, and the time-varying equation of viscosity of sulfur aluminate cement slurry was obtained by fitting. A set of fault fracture zone permeation grouting test system was developed, and a fault fracture zone grouting simulation test was carried out. The study shows that the diffusion distance calculated without considering the influence of slurry diffusion path and seawater is 1.63–1.91 times of the test value, which obviously overestimates the diffusion distance; the diffusion distance calculated with considering the influence of diffusion path and seawater is 1.06–1.35 times of the test value, which is in good agreement with the test value. The research results can provide some theoretical support for the design of grouting in seawater environment. [ABSTRACT FROM AUTHOR]