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An experimental and numerical investigation of influencing factors of gravel vibratory compaction

Construction and Building Materials 2025年 473卷

作者： Liu, Zhenxing Fan, Chengzhou Min, Yintong Liu, Chun Li, Shiguo Li, Yanxia Liang, Xiaodong Northwest Institute of Nuclear Technology Xi'an710065 China School of Earth Sciences and Engineering Nanjing University Nanjing210023 China

Vibration compaction is an effective method for improving sand foundations. To investigate the influence of vibration parameters and gravel gradation on vibratory compaction, a series of vibratory compaction tests with different vibration parameters and gravel gradations were carried out. A three-dimensional vibratory compaction simulator based on the discrete element software MatDEM was established. The effects of vibration frequency, nominal amplitude, and friction coefficient on final porosity were investigated. The results indicate that the vibration compaction effect is mainly determined by static pressure and excitation force, with the excitation force being the primary factor. The wider the gradation of the specimen, the lower the porosity. The lowest porosity is achieved at the vibration frequencies between 20 and 30 Hz, close to the resonance frequency. The porosity decreases with increasing amplitude in the range of 0.6–2 mm, associated with an increase in the compaction work. The vibration compaction effect is influenced by both friction coefficient and static pressure. When the friction coefficient is low, the porosity decreases with increasing static pressure. However, when the friction coefficient is great, a high static pressure produces large friction forces between particles, resulting in a greater porosity. © 2025 Elsevier Ltd

关键词： Gravel

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Performance analysis of a rotating detonation turbine engine considering operating condition limitations

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Aerospace Science and technology 2025年 162卷

作者： Wang, Ying Wen, Fengbo Su, Liangjun Han, Jiajun Zhao, Zhiyuan Luo, Yuxi School of Energy Science and Engineering Harbin Institute of Technology Heilongjiang Harbin150000 China Suzhou Research Institute of HIT Jiangsu Suzhou215000 China

This paper presents the construction of a thermodynamic model specifically suited for a rotating detonation turbine engine. It takes into account the actual operating conditions of an aircraft engine, including limitations on the turbine inlet temperature. The study investigates the thermodynamic cycle performance, pressure gain characteristics, energy-saving properties, and economy of the rotating detonation turbine engine. The results show that when the compressor pressure ratio remains consistent, the indicators of the rotating detonation turbine engine are better, and the advantages are obvious at low pressure ratio and high turbine inlet temperature. Under the working conditions selected in this paper, the thermal efficiency can be increased by up to 11.5% and the fuel consumption can be reduced by up to 12.8%. When the total pressure ratio of the engine is consistent, the compressor power consumption of the rotating detonation turbine engine is significantly reduced, which can reduce the number of compressor and turbine stages and improve the engine thrust-to-weight ratio. The influence of varying flight conditions on engine performance was also examined, offering guidance for parameter selection across different scenarios. Combined with the numerical calculation results, the engine's thermodynamic model was characterized using the actual rotating detonation process, and the performance of the rotating detonation turbine engine was evaluated more accurately. The results show that the rotating detonation process experienced by the working fluid in the rotating detonation combustor is in good agreement with the Humphrey model. The cycle curve obtained by two-dimensional numerical calculation is basically consistent with the ideal model. The difference in thermal efficiency calculated by the two methods is 0.3% at the minimum and no more than 10% at the maximum. © 2025 Elsevier Masson SAS

关键词： Thermolysis

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Collision Avoidance for Unmanned Surface Vehicles Based on the PPO with DBSCAN Algorithm

Collision Avoidance for Unmanned Surface Vehicles Based on t...

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International Conference on Artificial Intelligence and Autonomous Transportation, AIAT 2024

作者： Yu, Hui Wu, Defeng Li, Guoqiang Li, Yuqin School of Marine Engineering Jimei University Fujian Xiamen361021 China Fujian Provincial Key Laboratory of Naval Architecture and Ocean Engineering Fujian Xiamen361021 China Fujian Institute of Innovation for Marine Equipment Detection and Remanufacturing Industrial Technology Fujian Xiamen361021 China

ISBN: (纸本)9789819639762

Unmanned surface vehicles (USV) have gained a significant position in ocean resource development due to their cost-effectiveness and safety. Collision avoidance is the crucial technology determining whether a USV can complete resource exploration missions. This paper proposes a novel collision avoidance algorithm incorporating designed clustering algorithm and improved deep reinforcement learning (DRL) consisting of two parts. The improved collision avoidance algorithm involves collision risk assessment based on the Density-Based Spatial Clustering of Applications with Noise (DBSCAN) Algorithm used to classify obstacle ships. Secondly, Proximal policy optimization. Finally, multi-ship collision avoidance simulation platform is established to verify the reliability of the proposed algorithm. The simulation results show the higher collision avoidance success rate than traditional algorithms. © Beijing Paike Culture Commu. Co., Ltd. 2025.

关键词： Risk assessment

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Maximizing Business Process Efficiency in Industry 4.0: A Techno-Functional Exploration of Process Mining Tools

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Operations Research Forum 2025年第1期6.0卷 1-34页

作者： Bhaskar, Hari Lal Osama, Mohammad Reeta School of Commerce & Management Starex University P.O. Bhorakalan Haryana NH-48 Binola Gurugram 122413 India Department of Humanities and Management Madan Mohan Malviya University of Technology Uttar Pradesh Gorakhpur 273010 India Institute of Technology Department of Computer Science & Engineering Shri Ramswaroop Memorial University Lucknow-Deva Road Uttar Pradesh Barabanki 225003 India

This paper examines business process optimization through process mining in the context of Industry 4.0 using a qualitative research approach. It underscores how process mining facilitates microeconomic principles and efficiency and discusses a techno-functional approach to realizing BPM value, which can propel organizational change management. By analyzing secondary data, the study identifies key process mining tools relevant to Industry 4.0 and BPM, establishing selection criteria and exploring real-world applications. A hypothetical case study demonstrates the role of process mining in enhancing predictive maintenance and asset management by analyzing established processes. Additionally, the paper provides a tactical roadmap and a comparative framework for selecting tools aimed at optimizing or re-engineering business processes applicable across various business functions. It highlights how digitally enabled organizations can leverage data-driven insights to revamp legacy systems and achieve operational excellence. © The Author(s), under exclusive licence to Springer Nature Switzerland AG 2025.

关键词： Business process improvement Business process management Industry 4.0 Process mining Techno-functional

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Structure and mechanical properties of 3D printed biomimetic multi-tubular carbon fiber composites

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Fuhe Cailiao Xuebao/Acta Materiae Compositae Sinica 2025年第5期42卷 2557-2567页

作者： Yang, Fanghong Fu, Yunchen Zhong, Jiaming Zhang, Daijun Xin, Zhonghua Guan, Bowen Wang, Chengbo Ye, Lu Huang, Wei AECC Beijing Institute of Aeronautical Materials Beijing100095 China National Key Laboratory of Advanced Composites Beijing100095 China School of Materials Science and Engineering Huazhong University of Science and Technology Hubei430074 China

Inspired by energy absorbent natural tubular biological structures, a bionic multi-tubular carbon fiber composite was designed. This bionic material was fabricated using 3D printing and UV curing, incorporating heterogeneous interfaces to significantly enhance toughness and impact resistance. Experimental results demonstrate that the bionic structure material exhibits an extended yield phase and exceptional deformation recovery in static compression tests, with the specific energy absorption of 44.6 J/g and specific strength of 130.6 MPa/(g·cm–3). In three-point bending tests, the material shows a prolonged plastic deformation region. The fracture toughness is 1.54 times compared to carbon fiber composite. For impact tests, it effectively absorbs energy with restricted crack propagation, and the destruction of heterogeneous interface. This study provides biomimetic insights for the design of impact-resistant composite materials. © 2025 Beijing University of Aeronautics and Astronautics (BUAA). All rights reserved.

关键词： Carbon fibers

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Design and Synthesis of Novel Piperidine Urea Derivatives with Neuroprotective Properties

Pharmaceutical Fronts

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Pharmaceutical Fronts 2025年第1期7卷 e32-e40页

作者： Li, Jiayi Wang, Mengfei Jiang, Ling Peng, Xinyan Han, Bo Zhang, Qingwei Novel Technology Center of Pharmaceutical Chemistry Shanghai Institute of Pharmaceutical Industry Co. Ltd. China State Institute of Pharmaceutical Industry Co. Ltd. Shanghai China School of Chemistry and Chemical Engineering Shanghai University of Engineering Science Shanghai China National Key Laboratory of Lead Druggability Research Shanghai Institute of Pharmaceutical Industry Co. Ltd. Shanghai China

Ischemic stroke remains the leading cause of death worldwide, and in experimental studies of ischemic stroke, neuroprotective agents may display good efficacy. In our previous work, Fenazinel showed promising neuroprotective effects and entered phase I clinical trials in China. However, some side effects have limited its further study. To explore novel neuroprotective agents with higher potency and lower cardiotoxicity, in this work, a series of Fenazinel derivatives with piperidine urea groups (A1-A13) were designed and synthesized. The neuroprotective effect of A1-A13 was evaluated in human neuroblastoma cells (SH-SY5Y) by assessing cell survivals, and then in a rat model of middle cerebral artery occlusion (MCAO) by assessing the cerebral infarction area. The hERG (human ether-a-go-go -related gene) inhibitory activity was conducted to predict the cardiotoxicity of compounds. The hypoxia tolerance assay of mice was assessed by determining the survival time of mice in a sealed bottle. Our experimental data suggested that among the compounds, compound A10 demonstrated superior protective activity against SH-SY5Y cells at different concentrations, lower cytotoxicity compared with Fenazinel, and additionally, a weak cardiotoxicity (hERG IC ₅₀ > 40 μmol/L). Compound A10 not only effectively prolonged the survival time of mice, but also significantly reduced the percentage of cerebral infarction in MCAO rats with a dose-dependent tendency. In summary, this paper provides a reference for the rational structural medication of Fenazinel to reduce cardiotoxicity and finds compound A10 with better neuroprotective activity. © 2025 The Author(s). This is an open access article published by Thieme under the terms of the Creative Commons Attribution License, permitting unrestricted use, distribution, and reproduction so long as the original work is properly cited.

关键词： Fenazinel ischemic stroke neuroprotection piperidine urea derivatives

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Auto-tuned Active Filter Design for Lighting System in Buildings

Auto-tuned Active Filter Design for Lighting System in Build...

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International Electrical engineering Congress (iEECON)

作者： Natthanon Phannil Sulee Bunjongjit Santipont Ananwattanaporn Department of Instrumentation and Electronics Engineering Faculty of Engineering King Mongkut’s University of Technology North Bangkok Bangkok Thailand Faculty of Engineering Rajamangala University of Technology Rattanakosin Nakhon Pathom Thailand School of International and Interdisciplinary Engineering Programs School of Engineering King Mongkut’s Institute of Technology Ladkrabang Bangkok Thailand

ISBN: (数字)9798331543952

ISBN: (纸本)9798331543969

The lighting system is a continuously used energy system found in all buildings. This system is highly complex as it includes various types such as incandescent bulbs, fluorescent tubes, HID lamps, and LEDs. These types of loads consist of many electronic components and are significant sources of Auto-Tuned Active Filter signals. These harmonic signals directly affect protective devices and electronic equipment in the building's electrical system. Therefore, reducing the harmonic signals generated by the lighting system is crucial for buildings. Generally, harmonic reduction can be achieved by installing one of three types of filters: active, passive, and hybrid. This research presents the design of an auto-tuned active filter using the MATLAB Simulink and tests it using four lighting load cases. The designed circuit can effectively reduce harmonic signals while also improving the energy efficiency of the building.

关键词： Total harmonic distortion Technological innovation Software packages Buildings Lighting Harmonic analysis Active filters Attenuation Power harmonic filters Standards

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Predictive Maintenance in Autonomous Systems using Improved Support Vector Machine

Predictive Maintenance in Autonomous Systems using Improved ...

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Intelligent Systems and Computational Networks (ICISCN), International Conference on

作者： Mamatha Bai B G N. Sree Divya Ammar Hamedshnain S. Senthil Kumar T. Vasumathi Department of Computer Science and Engineering Nitte Meenakshi Institute of Technology Bengaluru India Department of Information Technology Mahatma Gandhi Institute of Technology Hyderabad India Department of Computers Techniques Engineering College of Technical Engineering The Islamic University Najaf Iraq Department of Electrical and Electronics Engineering New Prince Shri Bhavani College of Engineering and Technology Chennai India Department of Electronics and Communication Engineering Gojan School of Business and Technology Chennai India

ISBN: (数字)9798331529246

ISBN: (纸本)9798331529253

In recent years, rapid development in the domain of Predictive Maintenance have resulted in improved equipment lifetime span, decrease maintenance costs and reduced the unplanned downtime. Predictive maintenance is an approach that addresses any equipment or component failures in the systems proactively. However, integration of this approach in automated systems has several challenges such as ensuring the accuracy of fault predictions, management of large-scale data and maintenance of system reliability under various operational conditions. To overcome these challenges Improved Support Vector Machine (ISVM) is proposed. Initially, the data is collected from the Predictive Maintenance Dataset (PMD) and the preprocessing is performed through Inter Quartile Range (IQR) which enhances the quality of data and modeling efforts. Further relevant features are extracted using Recursive Feature Elimination (RFE). Finally, the prediction is performed using ISVM which achieved better outcomes compared to existing a One-Class Support Vector Machine (SVM) in terms of accuracy as well as recall by achieving 90.58%, 80.79% respectively.

关键词： Support vector machines Temperature sensors Vibrations Accuracy Autonomous systems Predictive models Feature extraction Maintenance Sensors Predictive maintenance

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A human–machine shared dual fuzzy authority allocation control strategy for automatic driving vehicle considering driver intention judgement

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Expert Systems with Applications 2025年 274卷

作者： Wang, Weida Zhang, Yunpu Yang, Chao Zhang, Yuhang Gao, Yipeng Ma, Taiheng Qie, Tianqi School of Mechanical Engineering Beijing Institute of Technology No. 5 Zhongguancun South Street Haidian District Beijing100081 China

Human–machine co-driving is a driving process of human and machine complete driving tasks together in advanced driving assistance system, achieving a smooth transition from automatic driving to manual driving. In this process, both human driver and automatic system remain in the control loop according to their respective control intentions. Human–machine shared control achieves the dynamic allocation of driving authorities. Therefore, the intention consistency and driving authority allocation strategy of human-machine will affect vehicle driving safety. How to allocate control authority in consideration of human–machine intentions is a key challenge. To address this issue, this paper proposes a shared control strategy based on dual fuzzy authority allocation considering driver intention judgement. First, as the basis of driving authority allocation, the driver takeover request recognition scheme based on the torque threshold considering real driver characteristics is proposed. The threshold is determined by data collected on a steer-by-wire test bench and processed through K-means clustering algorithm. Then, based on human–machine relationships and quantitative evaluation of driving characteristics, a dual fuzzy authority allocation controller with different emergency and auxiliary correction rules is designed to allocate control authorities. Finally, the proposed strategy is verified across diverse scenarios by driver-in-the-loop tests. Results indicate the proposed strategy reduces emergency obstacle avoidance time by 35% in conflicting scenarios, while reducing lateral offset and yaw errors by 53.89% and 11.11% in cooperative scenarios, compared to fixed-weight authority allocation strategy. © 2025 Elsevier Ltd

关键词： Advanced driver assistance systems

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Synergistically Improving the Strength-Impact Toughness in Dual-Phase Titanium Alloy via Martensite-Engineered α+α′+β Microstructure

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Journal of Alloys and Compounds 2025年 1026卷

作者： Hao, Pengfei Sun, Yanan Qi, Haoyue Li, Shan Fan, Qunbo Xu, Shun Yang, Lin Cheng, Xingwang School of Materials Science and Engineering Beijing Institute of Technology Beijing100081 China National Key Laboratory of Science and Technology on Materials under Shock and Impact Beijing Institute of Technology Beijing100081 China Beijing Institute of Technology Chongqing Innovation Center Chongqing401135 China

Titanium alloys exhibit low-temperature brittleness. A major challenge in their use has always been enhancing their impact toughness without compromising their strength. In this study, a dual-phase titanium alloy with α+ α′+ β phases was designed through alloying with Fe element, and its microstructure was carefully adjusted via heat treatment. The impact failure mechanism was analyzed through characterization in conjunction with molecular dynamics calculations. The designed Ti-6Al-2.5V-2Fe titanium alloy demonstrated a tensile strength of ∼1100 MPa, an elongation at break of ∼22 %, a room temperature impact toughness of ∼71.2 J/cm², and a low-temperature impact toughness of ∼54 J/cm², respectively. Compared to reported titanium alloys, it exhibits an excellent synergistic combination of strength and impact toughness, as well as good low-temperature impact toughness. These outstanding properties highlight its great potential for applications across both room and low-temperature environments. © 2025 Elsevier B.V.

关键词： Titanium alloys

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