bluuebunny/crossref_metadata_2025 huggingface dataset:
A possibilistic no-go theorem on the Wigner’s friend paradox
Authors: Haddara Marwan , Cavalcanti Eric G
Published: August 2023

The famous ‘Wigner’s friend’ paradox highlights the difficulty of modelling the evolution of quantum systems under measurement in situations where observers themselves are considered to be subject to the laws of quantum mechanics. In recent years, variations of the original Wigner’s friend paradox have been recognized as fruitful arenas for probing the foundations of quantum theory. In particular (Bong et al 2020 Nat. Phys.
16 1199) demonstrated a contradiction between a set of intuitive assumptions called ‘Local Friendliness’ (LF) and certain quantum phenomena on an extended version of the Wigner’s friend paradox. The LF assumptions can be understood as the conjunction of two independent assumptions: Absoluteness of Observed Events requires that any event observed by any observer has an absolute, rather than relative, value; Local Agency is the assumption that an intervention cannot be correlated with relevant events outside its future light cone. These assumptions are weaker than the assumptions that lead to Bell’s theorem, and thus while the LF result may be considered to be conceptually comparable to Bell’s result, its implications are even deeper. The proof of the LF no-go theorem, however, relies on probability theory, and a fundamental question remained whether or not LF is an inherently statistical concept. Here we present a probability-free version of the LF theorem, building upon Hardy’s no-go theorem for local hidden variables. The argument is phrased in the language of possibilities, which we make formal by using a modal logical approach. It relies on a weaker version of Local Agency, which we call ‘Possibilistic Local Agency’: the assumption that an intervention cannot affect the possibilities of events outside its future light cone.
Floquet engineering-based frequency demodulation method for wireless THz short-range communications
Authors: Herath Kosala , Nirmalathas Ampalavanapillai , Gunapala Sarath D , Premaratne Malin
Published: August 2023

This study introduces a novel theoretical framework for detecting and decoding wireless communication signals in the nanoscale range operating at terahertz (THz) frequencies. Initially, we investigate the Floquet states in a dressed 2D semiconductor quantum well and derive an analytical expression to determine its longitudinal conductivity. The results indicate that the longitudinal conductivity of a dressed 2D semiconductor can be tailored to specific requirements by manipulating the frequency of the external dressing field. Furthermore, carefully selecting the intensity and polarization type of the external dressing field enables fine-tuning and optimization of the conductivity. To evaluate the effectiveness of each dressing field configuration, we present a figure of Merit (FoM) assessment that determines the maximum possible change in conductivity within the considered frequency range. The proposed theory introduces a mechanism capable of identifying frequency-modulated communication signals in the THz range and performing frequency demodulation. We comprehensively analyze of the demodulator’s transfer function in the receiver. Consequently, we establish that the transfer function exhibits linear behavior over a specific frequency range, rendering it suitable for frequency demodulation. Finally, we provide a numerical illustration of a frequency demodulation scenario. The breakthrough uncovered in this study opens up possibilities for the development of high-efficiency, lightweight, and cutting-edge chip-scale wireless communication devices, circuits, and components.
Spatially flat spacetimes in higher dimensional Klein–Gordon-Rastall model
Authors: Ari Widianto Tegar , Khoirul Falah Ahmad , Eka Gunara Bobby
Published: August 2023

In this paper, we study higher dimensional Rastall gravity coupled to a scalar field with exponential scalar potential on spatially flat spacetimes. By using the dynamical system analysis, the background equation of motion, i.e. the Friedmann equations and the scalar field conservation, can be cast into a set of first-order differential equations and a constraint. We analyze the stability of the critical points from the theory. We also discuss the possible interpretation at the critical points with the cosmological expansion, in particular at the early- and late-time universe.
Quantitative modeling of EGF receptor ligand discrimination via internalization proofreading
Authors: Leblanc Jaleesa A , Sugiyama Michael G , Antonescu Costin N , Brown Aidan I
Published: August 2023

The epidermal growth factor receptor (EGFR) is a central regulator of cell physiology that is stimulated by multiple distinct ligands. Although ligands bind to EGFR while the receptor is exposed on the plasma membrane, EGFR incorporation into endosomes following receptor internalization is an important aspect of EGFR signaling, with EGFR internalization behavior dependent upon the type of ligand bound. We develop quantitative modeling for EGFR recruitment to and internalization from clathrin domains, focusing on how internalization competes with ligand unbinding from EGFR. We develop two model versions: a kinetic model with EGFR behavior described as transitions between discrete states and a spatial model with EGFR diffusion to circular clathrin domains. We find that a combination of spatial and kinetic proofreading leads to enhanced EGFR internalization ratios in comparison to unbinding differences between ligand types. Various stages of the EGFR internalization process, including recruitment to and internalization from clathrin domains, modulate the internalization differences between receptors bound to different ligands. Our results indicate that following ligand binding, EGFR may encounter multiple clathrin domains before successful recruitment and internalization. The quantitative modeling we have developed describes competition between EGFR internalization and ligand unbinding and the resulting proofreading.
Phase transitions in insect swarms
Authors: Reynolds Andy M
Published: August 2023

In contrast with laboratory insect swarms, wild insect swarms display significant coordinated behaviour. It has been hypothesised that the presence of a fluctuating environment drives the formation of transient, local order (synchronized subgroups), and that this local order pushes the swarm into a new state that is robust to environmental perturbations. The hypothesis is supported by observations of swarming mosquitoes. Here I provide numerical evidence that the formation of transient, local order is an accidental by-product of the strengthening of short-range repulsion which is expected in the presence of environmental fluctuations. The results of the numerical simulations reveal that this strengthening of the short-range can drive swarms into a crystalline phase containing subgroups that participate in cooperative ring exchanges—a new putative form of collective animal movement lacking velocity correlation. I thereby demonstrate that the swarm state and structure may be tuneable with environmental noise as a control parameter. Predicted properties of the collective modes are consistent with observations of transient synchronized subgroups in wild mosquito swarms that contend with environmental disturbances. When mutual repulsion becomes sufficiently strong, swarms are, in accordance with observations, predicted to form near stationary crystalline states. The analysis suggests that the many different forms of swarming motions observed across insect species are not distinctly different phenomena but are instead different phases of a single phenomenon.
Corrigendum: Gas exhaust in the Wendelstein 7-X stellarator during the first divertor operation (2022 Nucl. Fusion 62 096016)
Authors: Wenzel U. , Schlisio G. , Drewelow P. , Krychowiak M. , König R. , Pedersen T.S. , Bozhenkov S. , Haak V. , Kharwandikar A.K. , Lazerson S. , Naujoks D. , Perseo V. , Winters V.
Published: August 2023

In the published paper titled ‘Gas exhaust in the Wendelstein 7-X stellarator during the first divertor operation’ (2022 Nucl. Fusion 62 096016), figure 8 was incorrect. This corrigendum provides the correct figure 8.
MPP Tracking with a Modified Duty Cycle Sweeping (MDCS) Algorithm for Various Environmental Irradiance Conditions
Authors: Jusoh M A , Tajuddin M F N , Roslan M A
Published: August 2023

In this paper, a photovoltaic (PV) system based on modified duty cycle sweeping (MDCS) has been proposed to achieve the maximum power point tracking (MPPT). The disadvantages of perturb and observe (P&O), such as diverging tracking directions and the inability to detect the global peak during partial shading (PS), are intended to be overcome by this method (PS). An intelligent double identification and tracking method consistently tracks the global peak under partial shading and the MPP under rapid irradiance fluctuations. Strict dynamic irradiance and partial shading tests are imposed in MATLAB/Simulink@ and simulated to validate the suggested concept. Additionally, a laboratory prototype MPPT standalone PV system supported by Texas Instruments’ Code Composer Studio is operated by a SEPIC converter in conjunction with the C2000 real-time microcontroller in order to conduct an experimental validation study. The effectiveness of the method is compared with the other well-known MPPT techniques, conventional P&O. The suggested method successfully follows the global peak under various patterns of partial shading as compared to the conventional algorithms. The algorithm’s efficiency has been preserved at around 95-100%.
A Numerical Study of Collective Cell Migration in a Microchannel Driven by Surface Acoustic Wave (SAW) Device
Authors: Mazalan Mazlee Bin , Noor Anas Mohd , Wahab Yufridin , Johari Shazlina , Zakaria Mohd Rosydi , Zaman Wan Safwani Wan Kamarul
Published: August 2023

Collective cell migration is involved in a variety of biological contexts, including tissue morphogenesis, wound healing, and cancer invasion. Many studies have revealed that chemical, mechanical, and electrical stimulation all affect cell migration. Although an acoustic stimulus has been shown to influence cell migration in the past, the underlying mechanism is still unknown. A computational model that accounts for acoustic–structure interaction was constructed in this study to simulate the formation of a surface acoustic wave (SAW) field and the application of the acoustic pressure field on collective cell migration. A group of cells within a microchannel device and two ports of interdigitated transducers (IDTs) with different wavelengths were modeled. The stresses within cells were investigated as it was influenced by substrate displacement and pressure acoustic in the cell media generated by the SAW device. As a result, we observed the local stress within cells near the solid-fluid interfaces. For propagating SAW, the shorter wavelength of IDTs (600 μm) attributed to high stress at the cell’s top and bottom as compared to the SAW device with the longer wavelength (1000 μm). The standing SAW occurred underneath collective cells. The results of standing SAW on cell stress at the bottom confirm that the SAW device can be useful to regulate the abnormalities cellular activities associated with cell migration.
A Head-Mounted Assistive Device for Visually Impaired People with Warning System from Object Detection and Depth Estimation
Authors: Sae-jia Boonthicha , Paderon Rodolfo Lian , Srimuninnimit Thatchai
Published: August 2023

People with visual impairment use white cane as their traditional method for perceiving the surroundings. However, the utilization of a cane is limited by its length and orientation. In Thailand, the obstacles on paveway in daily life are not located only on the floor but also above knee level which sometimes could be harmful to pedestrians, especially blind people. A head-mounted assistive device is developed to be an enhancement used with a cane for the visually impaired to comprehend their environment both lower and higher the knee level. The assistive device is designed to be compact and light-weight. It could also send the tactile feedback as a warning from vibration motors mounted on the device. To generate a warning signal, YOLOv4 is used to detect the location of obstacles and depth map from the stereo camera is used to estimate the distance mapping into 4 defined ranges: dangerous, very close, close and fine. The results indicate that the head-mounted assistive device has the ability to perceive obstacles locating farther than 0.9 m. The prediction returned 9.23%, 14.63% and 7.86% error when estimating the depth of obstacles at 1.3 m., 2.8 m. and 4.2 m. respectively. The average execution time for the device to return the command controlling vibration motors is 0.13 second and the maximum estimated time for the motor to send the haptic feedback is 1.05 second.
Research on the Influence of Rub-impact Buffer Stroke on the Dynamic Response of Two-section Rotor
Authors: Wu Tingwei , Li Shitu
Published: August 2023

The two-section rotor needs to go through multiple critical speeds in the process of speed increase. When the rotor approaches the critical speed, its amplitude increases rapidly, easily causing collision damage. The auxiliary over-critical device cushions and protects the rotor through rubbing, which makes it pass the critical speed under the safe amplitude. In this paper, the influence of buffer stroke, the key structural parameter of the auxiliary over-critical device, on the dynamic response of the two-section rotor at the first-order bending critical speed is analyzed, the influence of its buffer stroke on the over-critical dynamic response of the rotor is calculated and analyzed, and the impact and friction force on the rotor is calculated. The design principles and results of the buffer stroke parameters of the auxiliary supercritical device are proposed.
Design and Optimization of PMSM for Injection Molding Machine
Authors: Huang Jinlin , Cao Guanghua , Zhang Li
Published: August 2023

With the implementation of the “dual carbon policy”, the traditional injection molding machine transmission system pays more and more attention to improving the energy efficiency for the drive motor, and the PM motor has obvious advantages in injection molding machine drive motor because of its high efficiency and high-power density. A permanent magnet servo motor (PMSM) for an injection molding machine with a rated power of 7 kW is designed based on the theory of PMSM in this paper. The 2D finite element analysis (FEA) model of the motor is set up. The electromagnetic performance parameters are obtained, including cogging torque, torque ripple, output torque, and no-load back EMF. The cogging torque of the motor is optimized and analyzed. The results show that the optimized motor has reduced the cogging torque and torque ripple without affecting the output capacity, which is more suitable for the application in the drive system of the injection molding machine.
Influence of Diameter Increase Speed on Diameter-Axial Rolling of Large 40Cr13 Stainless Steel Ring
Authors: Shi Zhiqi , Shi Liping , Cheng Sifu
Published: August 2023

Rolling speed ratios during the rolling process are critical to ring forming in this pepper. The selected roll feed mode is constant with the increasing speed of ring diameter during the main rolling stage. Based on Deform-3D finite element software, a large size ring with a diameter of φ1530 mm was taken as the research object. The numerical model of a large 40Cr13 stainless steel ring is established. The radial-axial rolling process of rings under different diameter increase speeds was simulated, and the changes in radial rolling force, temperature, and strain distribution of rings after rolling were analyzed under different diameter increase speeds. The results show that under the same conditions as other parameters, increasing the ring diameter increase speed has less effect on the temperature and equivalent standard deviation of variation inside the ring after rolling, but has more effect on the external surface, and both SDP and SDT decrease with the increase of ring diameter increase speed. The ring diameter increase speed on the maximum rolling force is more obvious, with the diameter increasing speed increasing. Using the rolling force, temperature standard deviation, and equivalent effect variation standard deviation as reference indexes, the diameter increase rate suitable for 40Cr13 rings is 6 mm/s.
Calculation and Analysis of Short Circuit Strength of Three-Winding Transformer
Authors: An Qi , Li Hongda
Published: August 2023

The transformer is the most important in the entire power system and is also one of the most expensive devices. The operating condition of the transformer affects itself and at the same time concerns the stability and safety of the whole power system. This paper deals with leakage field, short-circuit electromotive force, and other issues in the transformer. The basic data of the SFSZ-40000/110 power transformer is calculated as an example, and then the leakage field of winding and short-circuit electromotive force is calculated and analyzed.
Numerical Simulation of a Novel Flow Channel with Aligned Concave-Convex Cavities to Enhance the Performance of PEMFC
Authors: Chen Mengdong , Yao Wenzhuo , Deng Zhanfeng , Ma Meixiu , Tan Hui , Xu Guizhi , Hu Xiao , Xia Xiaojian
Published: August 2023

The bipolar plates are important components of fuel cells and its characteristics and cross-section shape have a significant influence on the performance of PEMFCs. A new-type flow channel with aligned fan-shape concave-convex cavities is presented. A 3D, single-phase model for PEMFC with the new-type flow channel is developed. The polarization curve, current density distribution as well as the oxygen concentration distribution of straight channel and the new-type flow channel are compared through CFD simulation. The performance of PEMFC with the new-type flow channel has been more improved than that with straight flow channels. The simulation results also show that the new-type flow channel with aligned fan-shaped concave-convex cavities improves the current density and the net power is increased by 2.6%. Moreover, the proposed novel flow channel is also very simple and inexpensive for manufacturing.
The influence of parameters of linear flat bottom chip breaker on chip flow
Authors: Chen Yingyi , Chen Shunqing
Published: August 2023

The simulation model of cutting TC4 titanium alloy with a YG8 cemented carbide tool is established through ABAQUS. The minimum width of the chip breaker, anti-chip surface angle, bevel angle of chip breaker, and the change of chip breaker front angle at the tooltip are changed by controlling other chip breaker parameters unchanged. Orthogonal tests are established under different edge angles to analyze the influence of the relevant parameters of the chip breaker on the chip angle and the influence of the change of the chip breaker parameters on the chip angle under different inclination angles. The results show that the chip breaker parameters affect the chip flow direction. The larger the groove spacing is, the smaller the chip flow angle first decreases and then becomes stable. The chip flow angle increases with the increase of the anti-chip surface angle, bevel angle of the chip breaker, and chip breaker front angle. The larger the inclination angle is, the more obvious the influence of chip breaker parameters is.
Driving Force of Electric Four-Wheel Drive Rodless Aircraft Tractor When Crossing Obstacles
Authors: Zhang Mingyang , Wang Haitao , Li Shiran , Qin Yugui
Published: August 2023

In this paper, the driving force of the electric four-wheel drive rodless aircraft tractor during obstacle crossing is monitored in real time, and the relationship between the four-wheel driving forces of the tractor under different obstacle-crossing conditions is analyzed. By comparing the influence of obstacle height, obstacle-crossing mode, initial obstacle-crossing speed, and wheel load on the obstacle-crossing driving force, the efficient obstacle-crossing method of the tractor is summarized. By analyzing the change of four-wheel driving force during obstacle crossing, the necessary theoretical and experimental basis is provided for the design and selection of a four-wheel drive rodless aircraft tractor.
Research on Dissipation Dilution Mechanism and Boundary Dissipation Suppression Technique for High-Stress Graphene Nanoelectromechanical Resonator
Authors: Liu Ying , Zhen Jia Peng , Yang Wen Xiang , Zheng Xian De , Guo Si Lin , Zhang Yong , Yang Peng , Lv Ke Hong , Qiu Jing , Liu Guan Jun
Published: August 2023

The low-quality factor is a key bottleneck for the engineering and commercial application of graphene nanoelectromechanical resonators at room temperature. The hypothesis in dissipation dominated by the ohmic loss is difficult to cover this phenomenon. Mechanical loss may still be on the list of the main causes for the quality factor stress-modulation characteristics of graphene resonators. The dissipation dilution theory reveals the intrinsic energy and dissipation mechanism of the traditional high-stress silicon-based resonator, which may also be applied to two-dimensional (2D) materials if dominated by mechanical loss. Based on Zener’s model of anelasticity, combined with the edge-corrected mode shape, the stress dilution mechanism of the bending potential dissipation of the graphene resonator is revealed. On this basis, the resonator dissipation is decomposed into boundary dissipation and non-boundary dissipation parts, and the steep rise phenomenon of the bending dissipation density (curvature) in the boundary region is analyzed through theoretical calculation. The analysis reveals that boundary dissipation is dominant in bending dissipation. To effectively suppress the boundary dissipation, a novel design of a graphene resonator via soft-clamped phononic crystal (PnC) is proposed. The existence of localized mode (LM) and effective suppression of boundary dissipation are verified in the simulations of both triangular and honeycomb PnC lattices. The theoretical model developed in this paper provides a new window into the dissipation properties of graphene nanoelectromechanical resonators, and the design of graphene resonators via soft-clamped PnC is expected to provide a new route toward high-quality factors at room temperature.
Dual-Layer Starch-based Biological Hydrogel Durable Evaporator for Efficient Solar Steam Generation
Authors: Xu Pengtao , Xia MengSheng , He Qian , Shi Qian , Gao Junkai
Published: August 2023

Solar-powered desalination is an effective means to address the global freshwater shortage and combat water pollution. However, the light absorption capacity, thermal insulation performance, and water transmission efficiency of most current solar evaporators cannot be effectively combined, resulting in a relatively low utilization rate of solar energy. In this study, a double-layer solar evaporator was reported by using starch as the biological hydrogel matrix and carbon nanotubes as an efficient light-absorbing material, which greatly improved the solar energy utilization rate of the evaporator and the steam generation efficiency was as high as 2.21 kgm−2h−1 under 1.0 sun.
Tension Characteristics of Cable-Driven System Based on ALE Formulation
Authors: Chen Da-Yuan , Zhang Huan , Song Xiao-Dong , Zhang Tian-ci , Hou Yue
Published: August 2023

This paper mainly studies the tension characteristics of cables in Cable-Driven Parallel Mechanisms (CDPMs). The exact catenary model and cable model based on the Arbitrary Lagrangian Eulerian description (ALE) are used. First, the ALE cable model and the exact catenary model are used to analyze and compare the tension at each point of a single cable, which proves the calculation accuracy of the ALE cable model. Then, the cable model described by ALE is used to model the Cable-Driven Parallel Mechanisms, the end effector is enabled to do a specific helical motion, the tension characteristics of the cable are extracted and analyzed, and the mesh independence of the ALE elements and calculation convergence are verified.
Structural Design and Static Calibration of Six-axis Force/Torque Sensor
Authors: Li Shuge , Zhao Pengju , Sun Wencheng
Published: August 2023

A six-axis force/torque sensor is designed to solve the problems of the sensor with a resistance strain gauge. For instance, if the adhesive layer of the resistance strain gauge is not firm, the elastic sensing beam will have plastic deformation. The cylindrical conductive rubber is used as the sensing unit, which can detect force/torque by the change of the piezoresistive values. The units are arranged in a spatial eight-point staggered manner, which can reduce the dimensional coupling from the structure. The sensor static calibration is systematically analyzed and researched. The linear decoupling model of the measurement system that incorporating the Least Squares algorithm is established to reduce the dimensional coupling. The new type of sensor structure and static linear calibration algorithm proposed in this paper have good practical applications and popularization values.
In Situ Biomaterial Printing Technology Based on Transfer Molding
Authors: Yuanyuan Liu , Zhian Jian , Yi Zhang , Huazhen Liu , Jie Wang , Jianan Chen
Published: August 2023

Skin is one of the largest and most important organs in the human body. When faced with a large, full-thickness skin burn, there is not enough healthy skin to graft. In this case, we can replace our skin with biomaterials. Due to its characteristics of water permeability, antibacterial properties, biocompatibility, self-debridement, and so on, the hydrogel is undoubtedly a better alternative material. Among the methods of hydrogel preparation, in situ material molding has attracted a lot of attention for its unique advantages. Here, we proposed an in situ forming process based on transfer printing and verified the feasibility of the transfer printing process using a three-axis platform. The in situ molding equipment was designed to realize the in situ material transfer process, which prepared the conditions for the subsequent process optimization, cell experiment verification, and animal experiment.
Microstructure and tensile properties of microalloyed Zn-xMg alloys
Authors: Zhang Tianwei , Zhang Mingyu , Liu Zhihui , Wang Weidan , Zhou Ke , Zhao Dewei
Published: August 2023

Zn-xMg alloys with different Mg contents were prepared by adding the Mg element to pure Zn. The effects of different Mg contents on the microstructure and tensile properties of Zn-xMg alloys were studied by scanning electron microscopy, XRD ray diffractometer, and tensile test. The results show that the microstructure of pure Zn and Zn-xMg alloys is composed of coarse grains, and there are twins in the microstructure morphology. The diffraction peak of pure Zn is mainly β-Zn. After adding the Mg element, α-Mg, and Zn2Mg11, diffraction peaks appear in the XRD diffraction pattern. With the increase of Mg content in the alloy, the number of Zn2Mg11 diffraction peaks increases. It is found that the strength and plasticity of the alloy increase with the increase of Mg content. The tensile fracture morphology of the alloy is mainly rock with or without the Mg element and has obvious brittle fracture characteristics.
The Correlation Between the Temperature Control Effect and Thermoelectric Properties of CNTs/Mn-Zn Ferrite Composites
Authors: Zhang Shupin
Published: August 2023

Mn-Zn ferrite has been widely used in cancer therapy. In this paper, CNTs/Mn-Zn ferrite composites with different CNT contents were synthesized using the co-precipitation process and then sintered into bulk materials by SPS. The nanoparticles have good heating and temperature control effects under an alternating magnetic field. Furthermore, the sintered composites have thermoelectric properties. The correlation between the temperature control mechanism and the thermoelectric properties of manganese zinc ferrite for thermotherapy is investigated.
Software Defined Network-Based Multi Service Routing Algorithm for Spatial Information Network
Authors: Wei Debin , Cao Yu , Teng Qixiu , Yang Li
Published: August 2023

In order to solve the problems of unbalanced utilization of link resources due to the different capabilities of nodes in the spatial information network and the difficulty of satisfying the quality of service(QoS) with the change of task requirements, this paper proposes a multi-service routing algorithm for a spatial information network based on Software Defined Network(SDN), which divides the network transmission services into three categories: delay sensitive, bandwidth sensitive and packet loss rate sensitive. The link state information between satellite nodes is collected by an SDN controller, and then the topology-based bidirectional search algorithm is used to establish a “Source-Destination” set of routes between satellite nodes, the algorithm counts the delay, bandwidth, and packet loss rate of each route in the set, and selects routes that meet the needs of different business classes for data forwarding. The results show that the routing cost of this algorithm is lower than other algorithms, and it has better throughput performance.
Ultra-short-term Photovoltaic Power Prediction Based on Multi-head ProbSparse Self-attention and Long Short-term Memory
Authors: Yang Tianyi , Zhao Quanming , Meng Yifan
Published: August 2023

To provide accurate predictions of photovoltaic (PV) power generation, an MHPSA-LSTM ultra-short-term multipoint PV power prediction model combining Multi-head ProbSparse self-attention (MHPSA) and long short-term memory (LSTM) network is posited. The MHPSA is first used to capture information dependencies at a distance. Secondly, the LSTM is used to enhance the local correlation. At last, a pooling layer is added after LSTM to reduce the parameters of the fully-connected layer and alleviate overfitting, thus improving the prediction accuracy. The MHPSA-LSTM model is validated on a PV plant at the Desert Knowledge Australia Solar Centre as an example, and the RMSE, MAE, and R2 of MHPSA-LSTM are 0.527, 0.264, and 0.917, respectively. MHPSA-LSTM has higher prediction accuracy compared with BP, LSTM, GRU, and CNN-LSTM.
Fault diagnosis for battery pack in electric vehicles using thresholds for multiple safety indicators
Authors: Wang Yi , Luo Shaohua , Ou Yang , Bai Qin , Zhang Wendong
Published: August 2023

A reliable and timely thermal runaway alarming method is useful to avoid potential fires happening to electric vehicles (EVs). In this paper, fault diagnosis for the battery pack in EVs using thresholds for multiple safety indicators. Firstly, a deep neural network is used to predict temperature and voltage in the future. Then both voltage-related and temperature-related safety indicators are extracted, including extremum entropy, variance entropy, cumulative center distance, and temperature rise rate. Their corresponding thresholds are defined using a boxplot. Verification using real-world fired EV data shows that the proposed method could realize 10–13 min ahead thermal runaway alarming.
Research on the operation state prediction of energy storage unit based on neural network
Authors: Yin Changyong , Zhao Ziqi , Zhang Shiqi , Gao Zexiang
Published: August 2023

As a device that can conduct energy storage and release, the energy storage system can accelerate the utilization of new energy and enhance the operation stability of the grid. The main significance of the time series prediction is to analyze the future change trend of the data based on historical data. To more exactly predict the future change trend of the operating state parameters of the energy storage unit, the charge and discharge current data and operating voltage data of the energy storage unit are analyzed and studied. The long short-term memory is used to predict the operating voltage and charge and discharge current of the distributed energy storage unit.
Train operation scheduling optimization based on deep reinforcement learning
Authors: Yang Xue , Wang Huan , Li Lijuan
Published: August 2023

The impact of time delays caused by unexpected events on trains spreads along the complex and widely distributed area of the high-speed railway network. Large train arrivals and departures are delayed. Serious social impact and huge loss of economic benefits are incurred. To solve the problems, the dynamic scheduling model of a high-speed train is established with the objective of minimizing the total delay time and energy consumption of the train. The DDPG algorithm is used to solve the model. The effectiveness of the algorithm for the dynamic scheduling of the high-speed train is verified through experiments, which provides a good basis for high-speed train dispatchers to make optimization decisions.
Comprehensive Improvement and Application of Copper Row Chain System of TOBSPIN Tobacco Cutter
Authors: Xu Min , Xu Li , Gong Jianqiang , Sun Kelei , Long Yue , Han Qiujing , Wang Miao
Published: August 2023

In order to solve the problem of abnormal wear of the lower copper row chain of TOBSPIN tobacco cutter, the working principle of the compaction unit of the wire-cutting machine was analyzed. Comprehensive improvements were made to the lower copper row chain system, which effectively reduced the wear on both sides of the copper row chain and prolonged the usage time of the copper row chain. Tested with TOBSPIN shredder used by Ningbo Cigarette Factory, the results showed that the wear speed of the improved copper exhaust chain was reduced from 2.62 mm / 800 h to 0.85 mm / 800 h, down by 67.6%. This method can support improving the service life of TOBSPIN tobacco cutters.
Study on Calibration of Oxygen Transmission Rate Measurement Apparatus for Plastic Film and Sheeting
Authors: Xu Yang , Liu Ying , Ren Tingting , Zeng Lingjian , Li Xianhong
Published: August 2023

The oxygen transmission rate measurement apparatus for plastic film and sheeting is mainly used to measure the oxygen transmission rate and oxygen transmission coefficient of plastic film and sheeting. Oxygen transmission tests can analyze and solve the problems caused by oxygen, such as oxidation deterioration. At present, there is no relevant calibration specification or method for oxygen transmission rate measurement apparatus for plastic film and sheeting in China. This article presents a novel calibration method to evaluate the measurement accuracy and temperature control performance of the apparatus by determining corresponding environmental conditions, calibration standards, and calculation equations. The calibration results show that the calibration method is scientific and practical for the metrological performance evaluation of oxygen transmission rate measurement apparatus for plastic film and sheeting.
Design and testing of automatic downpipe equipment for deep grain piles
Authors: Ming Lei , Zheng Jiahong , Shi Yue , Dong Jiahou
Published: August 2023

China is a large grain storage country, and at this stage, the effective storage capacity of the country has exceeded 900 million tonnes. Grain is subject to localized high temperatures, pests, and other abnormalities during storage. Therefore, regular quality checks need to be carried out on the grain, and cuttings are the first step in carrying out grain quality checks. The current domestic cutting equipment suffers from low cutting efficiency and high manual labor intensity, so the need to develop new cutting equipment is imminent. In response to the current problems with domestic cuttings equipment, this work has developed a deep grain pile automatic down tube equipment, which is driven by compressed air and is capable of completing cuttings within a ten-meter depth range in grain silos. Compared with traditional cutting equipment, this equipment greatly improves the efficiency of cutting samples, reduces manual labor intensity, provides new ideas for the development of automation of cutting equipment, and has a broad market.
Design and Simulation Analysis of the Patient Transfer Machine
Authors: Wen Shaoxin , Wang Xinzui , Cao Fucheng , Fu Hui
Published: August 2023

In response to the low level of automation of the tools used for patient transfer in hospitals and the resulting shortage of nursing personnel, this paper studies the characteristics of existing transfer products and related structural features. A transfer machine based on static transfer is proposed, which can achieve patient transfer between a hospital bed and a stretcher truck. In this paper, the overall structure of the transfer machine has been designed in detail, and the structural design and analysis of important transmission components have been carried out. The finite element strength analysis of the main bearing components has been carried out. Finally, the selection of driving components based on their functions has been carried out. This study provides theoretical and technical support for the development of subsequent transfer machines.
Design Method of the Civil Aircraft Cargo Compartment Interiors Based on Resist-flame Burnthrough
Authors: Zhang Huan
Published: August 2023

This paper aims to conduct research on interior design methods based on resist-flame burn-through. The paper first analyzed the acceptance criterion of the oil burner test according to part III of Appendix F, part 25, [1]. Then it elaborated on various design methods of cargo compartment liners combined with the previous design and test experience, including the design method of material, opening features, lap/butt joint features, and corner butt joint features [2]. These design methods can effectively improve the ability to resist-flame burn-through of cargo compartment liners.
Numerical simulation of directional solidification process of single crystal blade based on precast
Authors: Zhao Xiaoyun , Cao Guoqiang
Published: August 2023

A finite element method was applied to establish a mathematical model of a single crystal blade’s directional solidification process. The model had different angles between the axis of the mold group and the blade. The effects of different radiation angles on temperature variation laws at different blade positions were investigated. The temperature near the center was lower than that near the wall on the upper side of the baffle, while it was higher on the lower side. Moreover, the grain growth of stray particles in blade casting defects was influenced by blade orientation. The grain growth of scattering particles in blade casting defects was faster. The isolated solid-liquid mixing zone was more prone to form at the platform tip near the center when the blade orientation angle was smaller. The 0° orientation angle resulted in the blade’s most severe stray grain phenomenon.
Parameter Optimization for Temporary Primary Frequency Control of Wind Turbines Based on Analytical Derivation
Authors: Wei Xinyu , Jin Zhaoyang , Li Gengkun
Published: August 2023

DFIG has the capability to participate in power system frequency modulation through inertial control by returning the energy stored in the rotating mass of the generator that is delivered to the grid. When frequency modulation occurs, the primary frequency drop can lead to a reduction in the rotor kinetic energy stored in the DFIG, which is subsequently used to produce extra active power to sustain the system frequency. However, once the available rotor kinetic energy is released, the output power of the DFIG abruptly drops to restore the rotor speed. To reduce the extent of the secondary frequency deviation caused by the inertial control of DFIGs, this paper applies an analytically derived approach to optimize the parameters of temporary primary frequency control during rotor speed recovery. Specifically, the parameters optimized include termination time and active power Simulation results conducted using DIGSILENT simulation software have demonstrated that the optimized temporary primary frequency control strategy is capable of effectively reducing the secondary frequency drop that may occur when the DFIG is removed from frequency control. Moreover, setting the optimal termination time and controlling the active power output while the rotor speed is being restored are crucial to prevent excessive mechanical wear and fatigue that may be induced by a too-rapid recovery of rotor speed.
On the influence of head motion on the swimming kinematics of robotic fish
Authors: Abbaszadeh Shokoofeh , Kiiski Yanneck , Leidhold Roberto , Hoerner Stefan
Published: August 2023

Up to now bio-inspired fish-mimicking robots fail when competing with the swimming performance of real fish. While tail motion has been studied extensively, the influence of the head motion is still not fully understood and its active control is challenging. In this experimental study, we show that head yawing strongly impacts on the propulsion force and determines the optimal fin actuation amplitude and tail beat frequency when aiming for a maximal propulsion force. In a parametric experimental study on a tethered 367 mm long fish robot the pivot point location of the head yaw has been varied along with tail beat frequency and actuation amplitude. The experiments took place in a still water tank and the swimming force has been measured with a single axis load cell. The robot is actuated with non-conventional area actuators based on micro fiber composites. 105 parameter sets have been investigated while the highest pivot point distance of roughly 0.36 body length from the nose tip provided the highest propulsion force of 500 mN with the lowest actuation frequency of 2.5 Hz and the highest head motion amplitude of a magnitude of 0.18 body length. Even though the pivot point location on a free swimming robot is a consequence of the complex fluid-structure interactions of fish and fluid, the results provide valuable information for the design of fish mimicking robots and questions the paradigm that head yaw is a simple recoil effect from tail motion and has to be minimized for an effective propulsion.
Dams and tribal land loss in the United States
Authors: Randell Heather , Curley Andrew
Published: August 2023

Indigenous peoples in the United States have faced continued land dispossession for centuries. Through the reservation system as well as policies including forced removal and allotment, colonial settlers and later the federal government acquired over two billion acres from Native Nations. We argue that another important, yet understudied and unquantified, contributor to tribal land loss is through the construction of dams. By restricting water flow in rivers or lakes, dams submerge land under reservoirs and disrupt aquatic and terrestrial ecosystems. This impacts livelihoods of local communities, destroys culturally important places and resources, and displaces people from their homes and land. To quantify the amount of tribal land lost as a result of dam construction, we engage in an innovative data linkage project. We use geospatial data on the boundaries of federal Indian reservations and Oklahoma Tribal Statistical Areas (OTSAs) and overlay these data with the locations of approximately 7,900 dams in the continental US. We estimate that 139 dams have submerged over 619 000 acres of land on 56 federal reservations and that 287 dams have inundated over 511 000 acres of land on 19 OTSAs. Taken together, our lower-bound estimate is that over 1.13 million acres of tribal land have been flooded under the reservoirs of 424 dams, which amounts to an area larger than Great Smokey Mountains National Park, Grand Teton National Park, and Rocky Mountain National Park combined. In light of recent federal legislation to address aging infrastructure in the US as well as the increasing risks to dam function and safety caused by climate change, dams that impact tribal land should be prioritized for removal. In cases where removal is not a preferred or viable option, alternatives include tribal ownership or funding for repairs and improvements.
Covariant action for conformal higher spin gravity
Authors: Basile Thomas , Grigoriev Maxim , Skvortsov Evgeny
Published: August 2023

Conformal higher spin (HS) gravity is a HS extension of Weyl gravity and is a family of local HS theories, which was put forward by Segal and Tseytlin. We propose a manifestly covariant and coordinate-independent action for these theories. The result is based on an interplay between HS symmetries and deformation quantization: a locally equivalent but manifestly background-independent reformulation, known as the parent system, of the off-shell multiplet of conformal HS fields (Fradkin–Tseytlin fields) can be interpreted in terms of Fedosov deformation quantization of the underlying cotangent bundle. This brings into the game the invariant quantum trace, induced by the Feigin–Felder–Shoikhet cocycle of Weyl algebra, which extends Segal’s action into a gauge invariant and globally well-defined action functional on the space of configurations of the parent system. The same action can be understood within the worldline approach as a correlation function in the topological quantum mechanics on the circle.
Seven definitions of bipartite bound entanglement
Authors: Gaida Michael , Kleinmann Matthias
Published: August 2023

An entangled state is bound entangled if one cannot combine any number of copies of the state to a maximally entangled state by using only local operations and classical communication. If one formalizes this notion of bound entanglement, one arrives immediately at four different definitions. In addition, at least three more definitions are commonly used in the literature, in particular in the very first paper on bound entanglement. Here we review critical distillation protocols and we examine how different results from quantum information theory interact in order to prove that all seven definitions are eventually equivalent. Our self-contained analysis unifies and extends previous results scattered in the literature and reveals details of the structure of bound entanglement.
Using native plants as sustainable solution for controlling aeolian activities
Authors: Ahmed Modi M. , Dousari Noor Al , Abbar Adnan
Published: August 2023

Kuwait is experimenting with the restoration of severely degraded terrestrial regions in its northern region, center for the development of wildlife habitats. The re-implantation and reproduction of native plants project, which will run from June 2003 to May 2019, is the main part of the restoration of the degraded zones. The most effective plants for reducing aeolian mobile sediments were highlighted, along with the most endangered plant species in the area, including Lycium shawii, Haloxylon salicornicum, Rhanterium epapposum, Panicum turgidum and, Calligonum polygonoides. The irrigation of these plants was kept up for around one to two years using brackish water from a productive well that produced 20 to 26 m3 per hour (TDS=4, 900 ml/l) and was hydrogen sulfide-free. Maximum mobile aeolian sediments were captured in Nitraria, Haloxylon, Tamarix, Lycium, Panicum, and Citrullus at 11.17, 6.29, 6.09, 5.77, 5.60, and 5.51m3, respectively. Their relative economic values were 14.74, 8.3, 8.04, 7.62, 7.39 and. 7.27 $, making them the most effective controls for aeolian processes in both current and upcoming applications.