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Due to the high conductivity and low permeability of giant magnetostrictive materials (GMMs), eddy currents and temperature rise caused by these materials are unavoidable. These factors will significantly impact the output efficiency and reliability of giant magnetostrictive transducers (GMTs). It is essential to conduct precise evaluations of the output characteristics in various temperature settings to effectively design and optimize the transducer. However, to reduce the eddy current loss of GMMs, a radial slit is introduced. The intricate geometry also contributes to the complexity of analysis. According to the practical engineering requirements, this paper initially established a testing system for GMM characteristic and analyzed the mechanism between material temperature and output characteristics. Second, improvements have been made to the equivalent circuit method. Research has been conducted on the influence of temperature and eddy currents on the electrical and mechanical equivalent circuits, leading to the creation of a comprehensive equivalent circuit model for GMTs. Finally, a testing platform has been set up to assess the temperature-output characteristics of the transducer. The impedance and displacement characteristics of a GMT were examined to validate the proposed model. The test results demonstrated that within the 20 – 100 °C range, the discrepancy between the model and the measured impedance is under 1%, and the displacement amplitude error is less than 5%, thus confirming the precision of the proposed model. [ABSTRACT FROM AUTHOR]

Finding low-energy structures of ligand-protected clusters is challenging due to the enormous conformational space and the high computational cost of accurate quantum chemical methods for determining the structures and energies of conformers. Here, we adopted and utilized a kernel rigid regression based machine learning method to accelerate the search for low-energy structures of ligand-protected clusters. We chose the Au25(Cys)18 (Cys: cysteine) cluster as a model system to test and demonstrate our method. We found that the low-energy structures of the cluster are characterized by a specific hydrogen bond type in the cysteine. The different configurations of the ligand layer influence the structural and electronic properties of clusters. [ABSTRACT FROM AUTHOR]

A new approach for the calculation of eigenstates with the state-averaged (multi-layer) multi-configurational time-dependent Hartree (MCTDH) approach is presented. The approach is inspired by the recent work of Larsson [J. Chem. Phys. 151, 204102 (2019)]. It employs local optimization of the basis sets at each node of the multi-layer MCTDH tree and successive downward and upward sweeps to obtain a globally converged result. At the top node, the Hamiltonian represented in the basis of the single-particle functions (SPFs) of the first layer is diagonalized. Here p wavefunctions corresponding to the p lowest eigenvalues are computed by a block Lanczos approach. At all other nodes, a non-linear operator consisting of the respective mean-field Hamiltonian matrix and a projector onto the space spanned by the respective SPFs is considered. Here, the eigenstate corresponding to the lowest eigenvalue is computed using a short iterative Lanczos scheme. Two different examples are studied to illustrate the new approach: the calculation of the vibrational states of methyl and acetonitrile. The calculations for methyl employ the single-layer MCTDH approach, a general potential energy surface, and the correlation discrete variable representation. A five-layer MCTDH representation and a sum of product-type Hamiltonian are used in the acetonitrile calculations. Very fast convergence and order of magnitude reductions in the numerical effort compared to the previously used block relaxation scheme are found. Furthermore, a detailed comparison with the results of Avila and Carrington [J. Chem. Phys. 134, 054126 (2011)] for acetonitrile highlights the potential problems of convergence tests for high-dimensional systems. [ABSTRACT FROM AUTHOR]

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]

Investigating flexibility and stability boosting transmission expansion planning (TEP) methods can increase the renewable energy (RE) consumption of the power systems. In this study, we propose a bi-level TEP method for voltage-source-converter-based direct current (VSC-DC), focusing on flexibility and stability enhancement. First, we established the TEP framework of VSC-DC, by introducing the evaluation indices to quantify the power system flexibility and stability. Subsequently, we propose a bi-level VSC-DC TEP model: the upper-level model acquires the optimal VSC-DC planning scheme by using the improved moth flame optimization (IMFO) algorithm, and the lower-level model evaluates the flexibility through time-series production simulation. Finally, we applied the proposed VSC-DC TEP method to the modified IEEE-24 and IEEE-39 test systems, and obtained the optimal VSC-DC planning schemes. The results verified that the proposed method can achieve excellent RE curtailment with high flexibility and stability. Furthermore, the well-designed IMFO algorithm outperformed the traditional particle swarm optimization (PSO) and moth flame optimization (MFO) algorithms, confirming the effectiveness of the proposed approach. [ABSTRACT FROM AUTHOR]

The synthesis of multicomponent cocrystals and salts (MCCS) is an active and contemporary theme in the crystal engineering of pharmaceutical crystal forms. The self-assembly process of multiple molecular components to an ordered and organized crystalline structure becomes increasingly difficult and complex as more than two molecules are present, e.g., ternary, quaternary, and higher-order cocrystals (HOC). One of the most frequent synthetic pathways to promote the self-assembly is mechanochemistry, assisted by a small amount of solvent added. Herein we report a comparative study of two mechanochemical routes on a series of ternary drug systems, halogen bonded ternary cocrystals and quaternary molecular cocrystals: (1) the sequential addition of components in different orders, referred to as the M1 method. The nth component is added to the pre-formed adduct of n − 1 remaining components. (2) The addition of all the components (n) in a single step, referred to as the M2 method. In both methods solvent drop grinding (SDG) or liquid-assisted grinding (LAG) manual operation were used. An excellent match of the experimental PXRD pattern from M1 and M2 procedures with that of the calculated PXRD pattern calculated from single-crystal X-ray diffraction (SC-XRD) data was noted for a majority of the systems tested. The role of crystal seeds/nuclei in forming the multicomponent crystalline products was established under optimal conditions in a single-step synthetic protocol. Concurring positive results on quaternary systems validate the applicability of this method to HOCs. When in a few cases complete transformation to the ternary or quaternary phase was not observed after manual grinding, in such systems ball-mill grinding (BMG) proved to complete the cocrystallization. A simple, efficient and scalable grinding method for MCCS is reported which can be extended to higher-order multicomponent cocrystals. [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]

Sustainable professional integrity is the pivoting factor for maintaining the expected ethical standard of a profession. Whereas privacy of a user becomes vulnerable due to the digital transactions performed on the web. To this end, we propose a distributed framework, Jurisprudence, that preserves a user's privacy by preventing concurrent active sessions. The proposed model enables online transactions using one-time password (BLOCK-OTP) based blockchain multi-factor authentication. It encapsulates the users details and preserves the privacy of the user by preventing the invocation of concurrent transaction sessions. We deployed the system into the Ethereum test blockchain environment and tested the framework. We envisage our model to be suitable for the detection of fraudulent and malicious activities in near future. [ABSTRACT FROM AUTHOR]

Molecular‐recognition events are highly relevant in biology and chemistry. In the present study, we investigated such processes in the solid state under mechanochemical conditions using the formation of racemic phases upon reacting enantiopure entities as example. As test systems, α‐(trifluoromethyl)lactic acid (TFLA) and the amino acids serine and alanine were used. The effects of ball‐milling and resonant acoustic mixing (RAM) on the formation of racemic phases were probed by using solid‐state Nuclear Magnetic Resonance (NMR) spectroscopy. In a mixer mill, a highly efficient and fast racemic phase formation occurred for both TFLA and the two amino acids. RAM led to the racemic phase for TFLA also, and this process was facilitated upon employing pre‐milled enantiopure entities. In contrast, under comparable conditions RAM did not result in the formation of racemic phases for serine and alanine. [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]

Regulatory dose–response assessments traditionally rely on in vivo data and default assumptions. New Approach Methods (NAMs) present considerable opportunities to both augment traditional dose–response assessments and accelerate the evaluation of new/data-poor chemicals. This review aimed to determine the potential utilization of NAMs through a unified conceptual framework that compartmentalizes derivation of toxicity values into five sequential Key Dose–response Modules (KDMs): (1) point-of-departure (POD) determination, (2) test system-to-human (e.g. inter-species) toxicokinetics and (3) toxicodynamics, (4) human population (intra-species) variability in toxicodynamics, and (5) toxicokinetics. After using several “traditional” dose-response assessments to illustrate this framework, a review is presented where existing NAMs, including in silico, in vitro, and in vivo approaches, might be applied across KDMs. Further, the false dichotomy between “traditional” and NAMs-derived data sources is broken down by organizing dose–response assessments into a matrix where each KDM has Tiers of increasing precision and confidence: Tier 0: Default/generic values, Tier 1: Computational predictions, Tier 2: Surrogate measurements, and Tier 3: Direct measurements. These findings demonstrated that although many publications promote the use of NAMs in KDMs (1) for POD determination and (5) for human population toxicokinetics, the proposed matrix of KDMs and Tiers reveals additional immediate opportunities for NAMs to be integrated across other KDMs. Further, critical needs were identified for developing NAMs to improve in vitro dosimetry and quantify test system and human population toxicodynamics. Overall, broadening the integration of NAMs across the steps of dose–response assessment promises to yield higher throughput, less animal-dependent, and more science-based toxicity values for protecting human health. [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]

A highly specific and sensitive rapid two-signal assay was developed for the detection of Salmonella typhimurium in foods of animal origin. The invA gene of Salmonella was used as the biorecognition element and recombinase-assisted amplification (RAA) technology for signal amplification. By utilizing the specific recognition and efficient trans-cleavage activity of CRISPR/Cas12a, point-of-care testing (POCT) for S. typhimurium was achieved via lateral flow strips (LFS) and personal glucometer (PGM) biosensors as dual signal readout systems, with sensitivities of 33 CFU/mL and 20 CFU/mL, respectively. Users can select the appropriate test system on the basis of specific application requirements: LFSs are ideal for rapid onsite screening, whereas glucometer biosensors offer precise quantitative determination. This approach simplifies the use of large instruments and overcomes site constraints, demonstrating good accuracy and applicability in animal-derived samples, with significant potential for the detection of other pathogens and for use in restricted environments. [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]

Emotional blackmail is a way of communication that forces people around them to listen to their requirements by emotional pressure. It can easily lead to negative emotions and even psychological problems of the other side, then affect the communication effect. In order to detect emotional blackmail utterance in daily communication scenarios and improve the communication effect, this paper developed an emotional blackmail utterance detection system based on Chinese text similarity evaluation. Firstly, this paper labelled the collected data based on Susan Forward's emotional blackmail theory, and construeted an emotional blackmail corpus and a test set. Secondly, this paper analyzed the expression modes of emotional blackmail, and designed text similarity evaluation methods based on part of speech and semantic words respectively, then formed an emotional blackmail utterance detection algorithm based on Chinese text similarity evaluation. Thirdly, this paper carried out experiments on the constructed datasets. The average recall and F1-score of the proposed algorithm are 95.21% and 79.95% respectively, which are better than the compared algorithms. Finally, this paper integrated an emotional blackmail utterance detection prototype system based on the proposed algorithm. Under different testing conditions, system test results show that the average recall is 87.24%, which shows good robustness and detection performance. [ABSTRACT FROM AUTHOR]

External thermal insulation compound systems with wooden fibre insulation External thermal insulation composite systems are analysed in system tests with regard to their serviceability and stability. The tests have been developed over decades and harbour individual weak points. The prediction of load‐bearing and deformation behaviour using mathematical methods is not yet common in practice, but could save a great deal of time and money. Overall, an unsatisfactory situation has developed over the decades. As part of several projects, extensive experimental and computational investigations have been carried out on materials, material combinations and components, which should lead to a greater understanding of building physics and elasto‐plastic‐mechanical properties. The findings can help to predict the load‐bearing and deformation behaviour of ETICS with wood fibre insulation boards using mathematical methods. This article describes the procedure within a research project. The results of the work show the possibilities of simulation. [ABSTRACT FROM AUTHOR]

This article presents the main stages and results of the project "Mobile Space Environment Testing Equipment Development of "Metamorphosis" Prototype for Transportation Intermodal Traffic". For successful implementation of the project, the project has been divided into four stages: 1) Design calculations and design documentation for the design elements of the prototype; 2) Prototype software development; 3) Manufacturing of construction details and prototype assembly; 4) Industrial research and prototype testing. The goal of the project is, based on industrial research, to develop a prototype of the Mobile Space Environment Test Facility (MSTF) "Metamorphosis" transported in an intermodal environment, and to achieve the level of scientific and technical readiness of MSTF from TRL2 to TRL4 (by the scale of the European Space Agency (ESA)) for further development of the project. This project is unique and has no comparable analogues, as all existing test facilities are stationary. The project is implemented by Riga Technical University in cooperation with Cryogenic and Vacuum Systems Ltd. [ABSTRACT FROM AUTHOR]

Background Local Problem Methods Results Conclusions Unnecessary group and screens (G&S) can lead to unnecessary antibody investigations, use of technologist time, and laboratory resources.A baseline audit at our institution identified that 25% of G&S from the cancer center were unnecessary. We aimed to reduce the ratio of monthly G&S to CBC samples processed from the cancer center by 10% (from 0.034 to 0.031) by January 2024.This represents an interrupted time series design from November 2022 to January 2024. Using Plan Do Study Act (PDSA) cycles, we aimed to increase the use of an existing reflex testing system, termed “do not test.” When this option is selected, the blood bank will only process the G&S sample if specific CBC criteria are met (e.g., hemoglobin <9.0 g/dL). Educational sessions increased awareness of this feature and sought feedback from end‐users on its usability. With feedback, the design was updated to include a modifiable hemoglobin threshold for G&S testing, automatic re‐selection of the “do not test” feature for future G&S orders, and aesthetic changes to make the feature more visible.The percentage of samples with “do not test” selected increased from 7.2% to 63.0% (p < .0001) and the ratio of G&S to CBC specimens improved from 0.034 to 0.028, exceeding the target of 0.031. We noted an improvement in the appropriateness of G&S orders from 75% at baseline (n = 20) to 97.5% (n = 80) post intervention (p = .003).We describe an effective strategy to improve G&S utilization at our institution's cancer center using a reflex testing system. [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]

Solid ammonia dosing technology has been extensively researched in the last decade as an effective solution to address issues such as urea crystallization and carrier blockage in traditional selective catalyst reduction (SCR) systems. In this study, a comparison of nitrogen oxide (NOx) conversion efficiency between solid ammonia dosing (SAD) and Adblue dosing on a heavy-duty diesel engine SCR system was conducted. First, an engine emission test bench with SAD SCR and Adblue SCR systems was established. Subsequently, both dosing systems were tested and studied on the engine emission test rig. The results showed that the NOx conversion efficiency of SAD was slightly improved by approximately 2%–5% when the catalyst upstream temperature exceeded 250°C, compared with the Adblue system. This improvement can be attributed to the better mixing ability of SAD. Additionally, SAD demonstrated significant advantages in avoiding issues related to urea decomposition at low exhaust temperatures. Furthermore, similar results were observed in the emission cycle test results of the engine. Under the European steady-state cycle (ESC) and European transient cycle (ETC) conditions, the NOx conversion efficiency of SAD was only slightly higher than that of the Adblue system by about 2%. However, under the world harmonized transient cycle (WHTC) condition, where more low-temperature operating conditions are included, the beneficial weighted NOx conversion efficiency of SAD increased to approximately 7.4% at a release condition of 190°C. [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]

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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]