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A comprehensive numerical model is developed to simulate the growth of microalgae under light/dark cycling conditions. The purpose of this study is to predict the growth rate of Chlorella vulgaris cultivated in photobioreactors (PBRs) in order to improve the light conditions for microalgae and enhance the photosynthetic efficiency. Computational fluid dynamics (CFD) is used to simulate its internal hydrodynamic behaviors. The Lagrangian method is employed to track the movement of microalgae cells. The radiative transfer equation (RTE) is used to obtain light intensity distribution. The combination of light radiation field and microalgae cell motions is used to construct the light history and they are integrated into the model of the photosynthetic units (PSU) to calculate the microalgae growth rate. The numerical results demonstrate that enhanced light/dark cycling frequency with ordered mixing can promote efficient microalgae cultivation. The effect of the vortex flow field generated by the baffles in an air-lift PBR is analyzed for increasing microalgae growth rate. When using the 1:1 baffle spacing, the biomass production of microalgae is increased by 41.8% compared to the original PBR. [ABSTRACT FROM AUTHOR]

Developing high‐rate electrode materials is a critical enabler of fast‐charging Na‐ion battery (NIB). Prussian blue analog (PBA) with rapid charge transfer channels has shown significant potential as high‐rate NIB cathodes; however, the fast‐charging capability of reported PBA‐based anodes remains limited. This challenge primarily stems from the complete transformation of their original PBA‐based crystal structures during synthesis processes, resulting in loss of the inherent rapid charge transfer channels. Herein, a Ni‐Fe based PBA (Ni3[Fe(CN)6]2) with a representative PBA‐based crystal structure is presented as a prototype to investigate its potential as a NIB anode, and structural modification strategies are implemented to unlock its rapid Na‐ion storage. First, conversion reaction mechanism is demonstrated in the Ni3[Fe(CN)6]2 during sodiation, with a theoretical specific capacity of 357.2 mAh g−1. However, its reversible capacities after long‐term cycling and at high rates are low. To address these issues, structural optimization strategies including S incorporation, configurational entropy modulation, and coordination environment regulation are utilized. Consequently, its fast‐charging (≈40 s per charge with 245.0 mAh g−1 input) and excellent cycling capabilities are realized. This study demonstrates the feasibility of PBA as high‐rate NIB anodes, and promotes the further investigation into structural optimization strategies aimed at developing other fast‐charging electrodes. [ABSTRACT FROM AUTHOR]

Screw-groove piles, a new type of precast pile, are economically and environmentally friendly and improve the load-bearing performance of piles through a unique screw-groove structure. To reveal the load-transfer characteristics and bearing mechanism of the screw-groove pile, the axial force, load–settlement curve, skin friction, bearing capacity, and response characteristics of the foundation for piles under vertical loading were analyzed. Furthermore, a parameter analysis of the ultimate bearing capacity and material utilization of screw-groove piles was performed using the finite element method. The results demonstrate that the screw-groove pile had an ultimate bearing capacity 1.85 times higher than that of the circular pile, and its material utilization rate was 2.85 times higher. The screw-groove surface end resistance and pile-tip resistance formed a multipoint vertical bearing mode. It efficiently utilized the soil's shear strength and mobilized a larger volume of surrounding soil to share the load. The screw-groove structure increased the pile–soil interaction surface, thereby increasing the skin friction resistance of the pile. Additionally, increasing the inner radius of the screw groove boosts the pile's bearing capacity but may reduce material utilization. An optimal screw-groove spacing balances both factors, while excessive groove thickness lowers material use. The pile shows high sensitivity to soil parameters. [ABSTRACT FROM AUTHOR]

Cellulose‐based separator exhibits excellent electrolyte affinity, thermal stability, and mechanical strength, which acts as a promising alternative to commercial polyolefin separators in lithium metal batteries (LMBs). Fiber size in cellulose‐based separators plays a crucial role in determining their physicochemical structure and mechanical strength, as well as the electrochemical performance of corresponding LMBs. Herein, the fiber size in cellulose‐based separators was first time regulated to optimize their mechanical stability and the related battery performance. The influences of fiber size in the separator on chemical structure, mechanical properties, surface morphology, electrochemical behavior were investigated in detail, in which the underlying mechanism between separator structure and the related performance was elucidated. As a result, the separator optimized by fiber size regulation exhibited excellent thermal stability under 180 °C, good tensile strengths of 6.0 MPa and Young's moduli of 315.9 MPa, superior room temperature ionic conductivity of 1.87 mS cm−1, as well as significantly improved electrochemical performance of corresponding batteries. It can be concluded that structure optimization for cellulose‐based separator through fiber size regulation is an effective and indispensable approach towards high safety and high performance LMBs. [ABSTRACT FROM AUTHOR]

The design of structures to resist progressive collapse primarily focuses on enhancing structural safety and robustness. However, given the low probability of accidental events, such designs often lead to a negative cost–benefit. To address this problem, this paper uses risk analysis to optimize the progressive collapse resistance design of steel frame structures. The elements' cross-section design for the progressive collapse resistance of steel frame structures is optimized using genetic algorithms and SAP2000 23, which identify the structural model with the minimum robustness index while ensuring safety. The results show that the risk-based robustness index can effectively assess the cost of progressive collapse design. More importantly, the optimization model can rapidly identify the most cost-effective structural design solution that complies with progressive collapse resistance guidelines, enhancing the simplicity and usability of the structure design optimization process. Additionally, the integration of the SAP2000 API with Python 3.8 automation streamlines the parameterization process, minimizes manual errors, and enhances the precision and efficiency of the structural design optimization. Finally, the model's effectiveness is validated through a case study, where the refined single-frame structure shows a reduction in initial construction and collapse-related costs by 2.4% and 9.1%, respectively. Meanwhile, the three-dimensional frame shows a 2.9% rise in initial costs but a 13.5% decrease in total collapse-resistant design costs, illustrating the model's ability to balance safety with cost-effectiveness. [ABSTRACT FROM AUTHOR]

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

Copyright of Lubrication Engineering (0254-0150) is the property of Editorial Office of LUBRICATION ENGINEERING and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

To further improve the cooling performance and operation stability of system, the gas-liquid separator enhanced loop thermosyphon/vapor compression hybrid system was proposed. In the thermosyphon mode, the separator was used to reduce the pressure drop of fluid in the two-phase tube for improving the performance of steady-state heat transfer and start-up and the operation stability of system. In the vapor compression mode, the separator was used to make the saturated vapor into the condenser for increasing the mass flow rate in the condenser and enhancing the system coefficient of performance (COP). The simulation model of the hybrid system was developed to investigate the impact of structural parameters on thermosyphon mode performance. The difference of refrigeration performance between the new system and the conventional system in vapor compression mode was comparatively analyzed under the given structural condition of system. The results show that the system performance is the best when the inner diameters of two-phase tube and gas tube are respective 10 mm and 9 mm with separator height and total system height of respective 1.05 m and 1.45 m. Compared with the conventional system, the new system can achieve better performance under any operating condition, and the maximum COP of the new system is improved by 19. 70％. [ABSTRACT FROM AUTHOR]

Variable flow emitters are used in subsurface drip irrigation to address challenges in soil moisture transport. This study investigates the impact of flow channel structural parameters on the hydraulic performance and anticlogging ability of emitters using computational fluid dynamics (CFD) simulations and experimental tests. The results show that the realizable k–ε turbulence model can be used to simulate the flow field inside the variable flow emitter flow channel. The nRMSE between the measured (qm) and simulated (q) values of the flow rate is 11.23%, and the relative error between the measured (xm) and simulated (x) values of the flow index is 4.66%, which gives a high simulation accuracy. A polar analysis shows that the tooth angle (A) has the smallest effect on the effluent flow rate at 0.1 MPa (q0.1), x, and particle passage rate (η) of the variable flow emitter. Flow channel depth (D), tooth spacing (B), and tooth height (E) have a different order of precedence in the influence of the three indices, which are D > B > E > A, B > E > D > A and E > B > D > A, respectively. The value of η is positively correlated with the mean flow velocity (v) and the mean turbulent kinetic energy (k) in the flow channel, and η tends to increase and then decrease with the increase of x. The retention time of the particles in the flow channel is closely related to the magnitude of v and k. Three multivariate lin ear regression equations (R2 = 0.883–0.995) were constructed for q0.1, x, and η versus the flow channel structural parameters. The optimal design combination of channel structure parameters for different scenarios was determined using the scipy.optimize.minimize function in Python 3.8.0. The research results provide a reference for the optimal design of variable flow emitters. [ABSTRACT FROM AUTHOR]

Zinc‐based batteries are emerging as the most promising candidates for large‐scale energy storage devices due to their low cost, high safety, and long‐term storage. However, zinc‐based batteries encounter challenges stemming from undesirable side reactions and zinc dendrites on the anode, as well as dissolution on the cathode. Owing to their extremely small size, substantial surface functional groups, and adjustable structure, carbon dots (CDs) present considerable benefits in augmenting coulombic efficiency, expanding cycle life, and enhancing the rate functionality of zinc‐based batteries. Herein, this review delves into the surface modification and morphological regulation of batteries elements by CDs, CDs composites, and CDs derivatives. Moreover, it systematically encapsulates the application of CDs in zinc‐based batteries, underscoring the pivotal role of CDs in the advancement of electrode technology. Finally, the review highlights the impediments and proposes potential avenues for utilizing CDs in zinc‐based batteries. This review aims to facilitate the development of superior solutions and provide scientific insights into energy storage technologies. [ABSTRACT FROM AUTHOR]

Typical aspirated smoke detectors were investigated herein aiming at performance enhancement of aspirated smoke detectors. The adverse effects of airflow turbulence and vortex formation on the precision of smoke detection were mitigated by meticulous adjustment and design optimization of their internal structures. To accurately evaluate the efficacy of these structural improvements, comparative analyses were conducted by using simulation models. The results indicate that fans induce vortex phenomena at both inlet and outlet, removing the filter sponge area exacerbates airflow instability, and a circular arc design for the upper wall significantly improves airflow conditions. Additionally, flow uniformity was analyzed by employing area-weighted and mass-weighted uniformity indices to quantitatively assess the uniformity within the detector's internal flow field. The findings suggest that issues related to internal airflow turbulence and vortex formation can be effectively addressed through refined internal structural designs and wall optimizations, which thereby senhances the detection efficiency and operational stability of the detectors significantly. [ABSTRACT FROM AUTHOR]

Environmental pollution and global warming caused by fossil fuels have become increasingly serious issues. Therefore, it is urgent to explore novel strategies to obtain sustainable, renewable and clean energy. Fortunately, ambient energy harvesting technologies, which are receiving increasing attention, provide an optimal solution. Additionally, the investigation of two-dimensional (2D) materials represented by transition metal dichalcogenides (TMDs) significantly facilitates the advancement of ambient energy harvesting technologies due to their unique properties, enabling the application of ambient energy harvesting. Herein, we summarized recent advances in the application of TMDs in thermal energy harvesting, osmotic energy harvesting, mechanical energy harvesting, water energy harvesting and radiofrequency energy harvesting respectively. In the meanwhile, we listed some representative structure and device optimization strategies for enhancing the energy conversion performance of these ambient energy harvesters, aiming to provide valuable insights for future investigations towards further optimization. Finally, we highlight the pressing issues currently faced in the application of the TMDs ambient energy harvesting technologies and propose some potential solutions to these challenges. We aimed to provide a comprehensive review in the applications of the energy harvesting technologies, in order to provide innovative insights for optimizing existing TMDs-based technologies. [ABSTRACT FROM AUTHOR]

The rapid development of high-speed railway bridges in China has brought enormous challenges to the ballast bed stability on the bridge. With the increase in the bridge span, the bridge deformation under the temperature load increases gradually, as well as the stability difference of ballast bed between different regions. Moreover, the track vibration response under high-speed driving conditions is larger, which can easily cause differential settlement, flying ballast, and deterioration of the ballast bed, thereby affecting the bearing capacity and stability of the ballast bed. In view of this, this article summarizes relevant research work on a ballast bed on the bridge from the perspectives of the resistance, deformation, and acceleration response of the ballast bed. In addition, this study discusses the existing measures for improving the ballast bed stability on the bridge, including the optimization of the sleeper and ballast bed structures. Finally, the main issues that need to be addressed to improve the ballast bed stability on the bridge are pointed out, and ideas for future research on ballast beds on bridges with different spans and structures are proposed. [ABSTRACT FROM AUTHOR]

ObjectivesThe localization of core components of heavy-duty gas turbines holds significant importance for technological innovation, industrial upgrading, and even national security. As a typical hot-end component of heavy-duty gas turbines, the performance of the turbine first-stage rotor blade directly determines the efficiency and reliability of the gas turbine. Therefore, the structure of the first-stage turbine blades of a certain heavy-duty gas turbine was optimized.MethodsBy increasing the number of bamboo nodes in the blade body, the blade cooling hole structure was optimized, and the thermal barrier coating was used to improve the blade coating. The temperature, stress distribution and aerodynamic efficiency of the blades before and after optimization under the service condition of the blade were compared and analyzed by fluid calculation and finite element calculation.ResultsHeat transfer efficiency inside the blade is enhanced by optimization of turbulent structure. Under the condition of the same inlet pressure of the cooling air, the surface temperature of the optimized blade is reduced by more than 50 ℃. Since the shape of the blade is not changed, there is little influence on the aerodynamic efficiency. Compared with the blades without optimization, the maximum equivalent stress and equivalent total strain of the optimized blade during service are significantly reduced.ConclusionsBy optimizing the cooling structure and upgrading the protective coatings, the reliability of the blades in high-temperature can be significantly improved. The research results provide a theoretical basis for the localization of gas turbines.

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

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

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

Under partial load operating conditions, vortex rope generation in the draft tube of a Francis turbine is considered one of the main reasons for hydro unit vibration. In this paper, a Francis turbine HLA551-LJ-43 in the laboratory was taken as a prototype. Numerical simulations of the entire flow passage were carried out. Four different hydro-turbines were chosen to analyze the effect of vortex suppression, which were named the prototype turbine (N-J), the turbine with J-grooves installed on its conical section (W-J), the one with extending runner cone (C), and the one that considered the J-grooves and the extending runner cone at the same time (J+C). Under the part load conditions in which the vortex rope is easily generated (0.4–0.8 times design flow QBEP), the spectrum characteristics of pressure fluctuation, the morphology of vortex rope, and the energy dissipation based on the entropy production theory in the draft tube were studied. The results show that the three optimized structures W-J, C, and J+C could reduce the pressure pulsation in the conical section of the draft tube, weaken the eccentricity of the vortex rope, and decrease the energy losses in the runner and draft tube. It is worth mentioning that the turbine with a J+C optimized structure had the most potent effect on vortex suppression and energy dissipation. Primarily when operating in deep partial load (DPL) conditions, the efficiency of the turbine with a J+C optimized structure was increased by 13.7% compared to the prototype turbine, and the main frequency amplitude of the pressure pulsation in the draft tube was reduced to 32% of the prototype. [ABSTRACT FROM AUTHOR]

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

Nowadays, magnetic bearing has been used in more and more fields. Displacement sensor is one of the most important functional components of a magnetic bearing system and have attracted more and more attentions. Inductance displacement sensor, which shows merits in maintainability, lifetime, sensitivity, environmental interference ability, and cost, is a potential displacement sensor for magnetic bearing systems. While, usually, for a certain application, installation space of displacement is limited, increasing the difficulty of sensitivity improvement by stator structure optimization. This paper presents a novel approach for axial inductance displacement sensor to improve sensitivity by decreasing the armature depth. In the experiment part, three armature with different depth have been fabricated and their performance are tested. The results show that sensitivity is improved from 2.34 mV/µm to 3.15 mV/µm when the depth of armature decreases from 24 mm to 18 mm, validating the feasibility of sensitivity improvement by decreasing the armature depth. With the improvement of sensitivity, resolution also improves from 5.1 µm to 3.8 µm. Negative effect of this approach is that measuring range is decreased when the armature depth is reduced. [ABSTRACT FROM AUTHOR]

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

In order to solve the problems of low loading efficiency and large load fluctuation of traditional thin seam shearer, taking the spiral blade of the drum as the research object, the variation law of the loading performance of the drum under different spiral lift angle was studied through discrete element simulation test. The results show these as follows When the spiral angle of the drum with a diameter of 1 200 mm is gradually increased, the loading efficiency of the drum is gradually increased from 73. 31% to 76. 56%. When the spiral angle reaches 18°, the optimal loading efficiency is obtained. When the spiral angle continues to increase from 18° to 30°, the loading efficiency of the drum is negatively correlated with the spiral angle. Based on the optimal spiral lifting angle, the structure of the spiral blades was optimized, and the simulation results showed that the loading efficiency of the drum was increased by 9. 94% and the load fluctuation was reduced by 22. 59%. [ABSTRACT FROM AUTHOR]

Enhancing the activity of oxygen evolution reaction (OER) is crucial for improving the efficiency of electrochemical water splitting (EWS). The highly adjustable electronic structure and potential high conductivity of transition metal sulfides (TMSs) make them promising candidates for OER electrocatalysts. Herein, we have synthesized trimetallic sulfides Fe 2 Ni 1 Zn 1 –S(II) based on layered double hydroxides (LDHs) precursor employing a facile and efficient two-step solvothermal approach. Benefitting from the multi-metallic synergistic effect and the distinctive interfacial structure, Fe 2 Ni 1 Zn 1 –S(II) shows excellent electrocatalytic OER performance (η 10 = 252 mV, Tafel slope = 64.2 mV∙dec−1). Meanwhile, it has outstanding stability (50 h) in 1 M KOH, which is better than RuO 2 and many other metal sulfide electrocatalysts. Furthermore, it was found that the structure of the catalyst was still retained after OER test, which further verified its catalytic stability. This work supplies an effective route for the preparation of LDHs derived multi-metallic sulfides. [Display omitted] • Modulation of the surface electronic structure of catalysts through multi-metal synergistic effect. • Layered double hydroxides offer a unique layered structure and high electrochemical activity. • Transition metal sulfides provide high electrical conductivity. • This study provides an effective way to further optimize the structure of transition metal sulfides. [ABSTRACT FROM AUTHOR]

To accurately grasp the stress distribution within the side plate of the vibrating screen box, a mechanical model has been developed, grounded in the plane stress theory of elastic mechanics. This model has subsequently been utilized to predict the stress distribution within the side plate, particularly when subjected to excitation forces arising from both unilateral and bilateral rotor arrangement structures. The results reveal that the mechanical model, which is firmly based on elastic mechanics, effectively captures the intricate stress patterns within the perforated side plate structure. Notably, the peak stress in a symmetrically distributed structure is significantly reduced, being merely half of that observed in a unilateral configuration. Additionally, the shear stress accumulated on both sides of the side plate acts to balance and consequently reduce the overall shear stress experienced by the plate. [ABSTRACT FROM AUTHOR]

This research uses a new method called the Modified Adolescent Identity Search Algorithm (MAISA) to solve optimization problems. The identity of a teenager is a different combination of thoughts, beliefs, and abilities that are obtained by him. He communicates with other people in society and tries to use the positive or negative feedback from these social interactions to shape his identity and become an independent person. Mathematical simulation of how adolescents' personality is formed during the mentioned process causes the emergence of this algorithm. The purpose of this research is to improve the performance of the AISA algorithm in the balance between exploration and exploitation. This algorithm isn't trapped in the optimal local points due to the appropriate convergence rate and reaches the universal optimal answer quickly. One of the features of this algorithm that we can mention is its simplicity and having few setting parameters. To show the effectiveness of this algorithm, results of solving two types of problems of mathematical functions and practical examples such as large-scale truss 120, 244, 942, and 72-bar truss, are measured by other similar algorithms. The results show that this algorithm has a good performance in the optimal solution of such problems, compared to other similar algorithms. [ABSTRACT FROM AUTHOR]

Accurate measurement of the pretightening stress for bolts has great significance for improving the assembly quality and safety, especially in severe environments. In this study, AlN thin film transducers were deposited on GH4169 nickel base alloy bolts using the RF magnetron sputtering, enabling a systematic investigation into the correlation between structures and the intensity of ultrasonic echo signals. Employing the finite element method resulted in consistency with the experimental data, enabling further exploration of the enhancement mechanism. With the increasing thickness of both the piezoelectric layer and the electrode layer, the intensity of the ultrasonic echo signals saw a great enhancement. The maximum-intensity observed increase is 14.7 times greater than that of the thinnest layers. Specifically, the thicker piezoelectric layer improves its mechanical displacement, while the increased thickness of the electrode layer contributes to better densification. An electrode diameter of nearly 4 mm is optimal for an AlN thin film transducer of M8 bolts. For pretightening the stress measurement, the sample with a strong and stable echo signal shows a low measurement error of pretightening below ±2.50%. [ABSTRACT FROM AUTHOR]

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

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

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

The shovel face inclination angle is a crucial parameter of the potato harvester digging shovel. Currently, there is limited research on the relationship between the inclination angles of curved digging shovel surfaces. The purpose of this study was to investigate the impact of the shovel face inclination angle on its soil crushing capacity in hilly terrain. A simulation model for the contact between the digging shovel and the soil was developed. The digging process of the shovel was simulated and analyzed under different shovel face inclination angles (α2). The analysis included comparisons of stress, Plastic Equivalent Strain (PEEQ), and energy. The results show that the larger the angle, the stronger its soil crushing ability; however, if the angle difference is too large, the phenomenon of soil flipping back occurs. When α2 = 16-17 °, the shovel length becomes excessive. When α2 = 18 °, the stress is too small. When α2 = 19 °, the energy is too large, and when α2 = 23-24 °, the PEEQ is too small. Therefore, the optimal shovel face inclination angle α2 is between 20 and 22 °, with fixed angles α1 = 15 ° and α3 = 13 °. [ABSTRACT FROM AUTHOR]

The development of novel nitride-based phosphors is always a significant work, especially for AlON system because of their rigid crystal structure, which is similar to the promising host material of β-SiAlON. In this work, Mg2+ ion was introduced into AlON-related phase Al 5 O 3 N 3 along with co-doped Si4+ ion used to keep charge neutrality, and thus a novel Mg-based nitroaluminosilicate MgAl 3 SiO 3 N 3 (MASON) was successfully synthesized under a mild preparation condition due to the high reactivity of MgO. Benefiting from its special crystal structure optimized by the introduction of Mg2+ ion, Eu2+-activated MASON performs significant photoluminescence (PL) and cathodoluminescence (CL) properties. In contrast to most Eu2+-activated AlON related phosphors that commonly emit high-energy blue light, the as-prepared sample emits a high-bright green light along with good thermal stability. Moreover, its broad emission band with the full width at half maximum (FWHM) of 134 nm well compensates the "cyan cavity", which leads to a full spectrum light-emitting diode. The structure-property relation of Eu2+ in MASON was established in this work, which confirms the significant role of the introduced Mg2+ ion in the structure optimization of AlON system. The result may pave an efficient way to explore more promising AlON-based phosphors. High-brightness green light emission was achieved in Eu2+-activated nitroaluminosilicate MgAl 3 SiO 3 N 3. [Display omitted] [ABSTRACT FROM AUTHOR]

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

This study introduces an integrated structural optimization design method based on a BP neural network and NSGA-II multi-objective genetic algorithm. Initially, a two-dimensional axisymmetric finite element model of the Giant Magnetostrictive Actuator (GMA) was established, and the coupling simulation of the electromagnetic field, structural field, and temperature field was conducted to obtain the GMA's performance parameters. Subsequently, the structural parameters of the GMA magnetic circuit, including the magnetic conducting ring, magnetic conducting sidewall, magnetic conducting body, and coil, were used as inputs, and the axial magnetic induction intensity, uniformity of axial magnetic induction intensity, and coil loss on the Giant Magnetostrictive Material (GMM) rod were used as outputs to establish a back propagation (BP) neural network model. This model delineated the nonlinear relationship between structural parameters and performance parameters. Then, the BP-NSGA-II algorithm was applied to perform multi-objective optimization on the actuator's structural parameters, resulting in a set of Pareto optimal non-dominated solutions, from which a set of optimal solutions was obtained using the entropy weight method. Finally, simulation analysis of this optimal solution was conducted, indicating that under a 5 A power supply excitation, the maximum axial magnetic induction intensity on the optimized GMM rod increased from 0.87 T to 1.12 T; the uniformity of axial magnetic induction intensity improved from 93.1% to 96.5%; and the coil loss decreased from 7.79 × 104 W/m3 to 4.97 × 104 W/m3. Based on the optimization results, a prototype actuator was produced, and the test results of the prototype's output characteristics proved the feasibility of this optimization design method. [ABSTRACT FROM AUTHOR]

Numerous efforts in the additive manufacturing literature have been made toward in-situ defect prediction for process control and optimization. However, the current work in the literature is limited by the need for multi-sensory data in appropriate resolution and scale to capture defects reliably and the need for systematic experimental and data-driven modeling validation to prove utility. For the first time in literature, we propose a data-driven neural network framework capable of in-situ micro-porosity localization for laser powder bed fusion via exclusively within hatch strip of sensory data, as opposed to a three-dimensional neighborhood of sensory data. We further propose using prior-guided neural networks to utilize the often-abundant nominal data in the form of a prior loss, enabling the machine learning structure to comply more with process physics. The proposed methods are validated via rigorous experimental data sets of high-strength aluminum A205 parts, repeated k-fold cross-validation, and prior-guided validation. Using exclusively within hatch stripe data, we detect and localize porosity with a spherical equivalent diameter (SED) smaller than 50.00 μ m with a classification accuracy of 73.13 ± 1.57 % This is the first work in the literature demonstrating in-situ localization of porosities as small as 38.12 μ m SED and is more than a five-fold improvement on the smallest SED porosity localization via spectral emissions sensory data in the literature. In-situ localizing micro-porosity using exclusively within hatch-stripe data is a significant step towards within-layer defect mitigation, advanced process feedback control, and compliance with the reliability certification requirements of industries such as the aerospace industry. [ABSTRACT FROM AUTHOR]

The high-power laser diode (HPLD) has witnessed increasing application in space, as the aerospace industry is developing rapidly. To cope with the space environment, optimizing the heat-dissipation structure and improving the heat-dissipation ability via heat conduction have become key to researching the thermal reliability of the HPLD in space environments. Based on a theoretical analysis of the HPLD, a simulation model of the HPLD was constructed for numerical simulation, and it was found that the maximum temperature and thermal resistance of lasers were efficaciously decreased by changing the packaging position of laser bars. The packaging position of the bars and the cutting angle of the microchannel heat sink (MCHS) were determined based on the light-emitting angle of the light-emitting unit and the internal structure of the MCHS. The internal structure of the MCHS was optimized through a single-factor experiment, an orthogonal experiment, and the combination of neural networks and genetic algorithms (GAs), using three key structural parameters, namely the MCHS ridge width, W1, the channel width, W2, and the channel length, L1. After optimization, the performance of the MCHS was obviously improved. Finally, an analysis was carried out on the applicability of the optimized MCHS to bars with a higher power. [ABSTRACT FROM AUTHOR]