Browse Topic: Logistics

Items (7,304)

Physics-Constrained Procedural Generation of Synthetic Environments for the Robust Validation of Autonomous Maneuver and Logistics

2026-01-7549

9/22/2026

The validation of Autonomous Ground Vehicles (AGVs) and intelligent logistics planners is frequently compromised by the ”Sim-to-Real” gap, where simulation environments fail to replicate the physical friction of operational deployment. Ideally, valid test cases must enforce strict mobility constraints and impose realistic sustainment penalties; however, many current generation tools rely on idealized terrain interactions and infinite-resource assumptions. We present a real-time procedural framework designed to generate high-friction validation environments that stress-test the robustness of the System Under Test (SUT). The architecture integrates gradient-based terrain analysis with a stochastic contested logistics model. It ingests synthetic heightmaps to precompute mobility corridors, ensuring that every generated evaluation episode adheres to vehicle-specific traversability limits. Simultaneously, a logistics kernel enforces fuel consumption scaled by terrain gradients and models supply chain interdiction as a parameterized Bernoulli process. We validate this framework through a ”Digital Twin” methodology, demonstrating that terrain-aware generation eliminates invalid initialization states (0% mobility violations) while the logistics model induces operationally relevant failure modes in the SUT. This unclassified, open-architecture approach supports DoD Verification, Validation, and Accreditation (VV&A) requirements by providing deterministic, reproducible edge cases for autonomous system evaluation.

Soykan, Bulent, Rabadi, Ghaith, Bochenek, Grace, Paul, Victor J.

Atomistic Molecular Dynamics Study of Linear and Branched Imidazole-Functionalized Polymers

2026-01-7548

9/22/2026

We present atomistic molecular dynamics simulations of linear and branched fluorinated polymer chains, with and without imidazole functionalization, designed as a model for solvent-free proton-conducting membranes for high-temperature fuel cell applications. Simulations conducted over a temperature range of 300 to 550 K, and diffusion-based relaxation times reveal that glass transition temperatures depend on polymer architecture: the branched and functionalized systems exhibit transitions near 400 K compared to 500 K for the linear chain. Fluorine-fluorine radial distribution functions demonstrate that branching disrupts local packing order, while imidazole substitution creates specific intra-chain interactions. Radius-of-gyration distributions reveal that branching significantly increases chain extension and creates multiple conformational families, whereas imidazole groups stabilize compact conformations at low temperatures that transition to more diverse states upon heating. These findings provide molecular-scale insight into how polymer architecture controls thermal transitions and structural organization in model high-temperature polymer electrolyte membranes.

Ganta, Sujith, Alim, Twaha, Rakesh, Leela, Mueller, Anja, Mellinger, Axel, Burye, Theodore, Sebastian, Talia

Mobilizing Innovation: Venture Capital Alignment for Defense with an Autonomous Construction Case Study

2026-01-7560

9/22/2026

Defense acquisition often struggles to match the pace of private investment, slowing the transition of mature commercial technologies into military use. This paper examines how aligning government acquisition with venture-oriented business models can increase industry participation, accelerate fielding, and reduce government program office risk. Using autonomous construction as a case study, it highlights how commercial investment has advanced autonomy while traditional procurement limits adoption. The paper outlines approaches such as non-traditional partnerships, phased acquisition, and performance-linked revenue structures to improve flexibility, leverage private capital, and expand the Defense Industrial Base while speeding operational capability delivery. Citation: Mazzara, M., San Nicolas, A., Gadea, J., Himmel, M., Kruger, J., Gill, C., & Simon, A., Soylemezoglu, A., Netchaev, A., Nottage, D., Klein, J. “Mobilizing Innovation: Venture Capital Alignment for Defense with Autonomous Construction Case Study” In Proceedings of the Ground Vehicle Systems Engineering and Technology Symposium (GVSETS), NDIA Michigan Chapter, Novi, MI, August 11–13, 2026.

Mazzara, Mark, Nicolas, Austen San, Gadea, James, Himmel, Max, Kruger, John, Gill, Charles “Spuck”, Simon, Andrea, Soylemezoglu, Ahmet, Netchaev, Anton, Nottage, Dustin, Klein, Jordan

Distributed Intelligence at the Tactical Edge: Enabling Contested Logistics in Degraded Networks

2026-01-7558

9/22/2026

Contested logistics environments expose the limitations of both legacy fragmented systems and emerging Next Generation Command and Control architectures that assume persistent connectivity. In degraded or denied conditions, sustainment operations face latency, bandwidth constraints, and reduced decision velocity. Expanded decision support tools further increase reliance on timely, relevant data exchange. This paper argues that contested logistics requires distributed, mission-aware intelligence at the tactical edge. Low-power onboard compute enables real-time inference, adaptive data conditioning, and connectivity-aware transmission across Radio-Frequency and non-RF pathways. By selectively elevating critical information based on mission context and network state, edge-intelligent architectures improve survivability, bandwidth efficiency, and sustainment effectiveness in degraded networks.

Baumann, Edward, Pardee, Shawn

Balancing Durability and Deployability: Enhanced Situational Awareness (ESA) for Non-Combat Tactical Vehicles

2026-01-7540

9/22/2026

The persistent rate of accidents and fatalities involving legacy tactical military vehicles underscores a critical need for Enhanced Situational Awareness (ESA) technologies. However, the prohibitive cost and lengthy development cycles associated with full MIL-STD ruggedization often prevent these safety systems from reaching the in-service non-combat vehicles with limited driver visibility. This paper suggests a strategic shift in procurement policy: The adoption of relaxed ruggedization standards for vehicles operating in non-combat, administrative, and training roles. By deriving requirements from high-stress commercial sectors— such as heavy mining, steel production, and NASCAR racing—the military can utilize electronics designed for "extreme industrial" rather than "battlefield" environments. The principal objectives of this relaxation is cost reduction, lowering the barrier to entry and increasing the likelihood of ESA deployment across the legacy fleet. Furthermore, this approach aligns with Modular Open Systems Approach (MOSA) principles by enabling the integration of non-proprietary commercial devices. Utilizing these accessible technologies on legacy platforms creates a real-world testbed to evaluate technological advances rapidly. These insights can then inform and accelerate the development of future MIL-STD systems for combat vehicles, effectively shortening the traditional development life cycle while prioritizing the immediate enhanced protection of service member lives.

Pilgrim, Robert A., Brown, Roy C.

Decision Engineering: Applying Lean Production Principles to the Lifecycle Decision Factory

2026-01-7525

9/22/2026

The Army’s transformation mandate is unambiguous: deliver warfighting capability 25–30% faster. Every Tier 2 metric published in support of that mandate – days between milestones, days to complete the requirements process, days to complete contracting, days to complete testing – is really a decision throughput measurement. Yet the systems engineering (SE) discipline that governs those timelines has no formal production framework for producing decisions. This paper proposes Decision Engineering as the framework. Grounded in lean production theory, applied to information work and anchored to the defense acquisition policy structure of DoDD 5000.01 and DoDI 5000.02, Decision Engineering reconceives SE as the discipline of designing, operating, and continuously improving the lifecycle decision production system. It introduces a formal decision ontology comprising six decision states (Latent, Declared, Active, Deferred, Closed, Reopened), four topology relationship types (Precedes, Enables, Constrains, Triggers), and five diagnostic biomarkers that measure production system health. The paper presents the Decision Factory model and describes how its application to ground vehicle system programs and across the Army acquisition enterprise can accelerate capability delivery without sacrificing rigor. Defense acquisition programs do not fail for lack of engineering rigor or digital tooling. They fail because the production system that converts information into decisions is ungoverned – no inventory count, no flow discipline, no throughput measurement. Decision Engineering names this production system, provides instruments to measure its health, and offers a practitioner framework for running it better.

Alexander, Eric, Foglesong, Matthew, Berklich, Louis (Bill)

From Crowdshipper Behavior to Urban Mobility Governance: Policy Insights for Sustainable Crowdshipping

2026-24-0029

9/21/2026

Crowdshipping has recently attracted significant attention as a potentially sustainable solution for urban logistics, as it leverages individuals’ underutilized travel capacity to perform last-mile deliveries. While existing research has extensively examined crowdshipper participation through motivational patterns, considerably less attention has been devoted to the governance and policy implications emerging from crowdshipper behavior. This represents a critical gap, particularly in the context of sustainable urban mobility, where logistics innovations are often implicitly assumed to generate positive externalities without adequate regulatory design. This paper addresses this gap by translating crowdshipper motivational evidence into policy-relevant insights for sustainable urban mobility planning. The analysis is based on data collected through a structured questionnaire administered to potential and active crowdshippers. The survey collected information on socio-demographic characteristics, mobility habits, motivations, risk perception, trust, and willingness to participate under alternative crowdshipping conditions. While such conditions are commonly used to estimate participation patterns, this study reinterprets them through a governance-oriented lens to explore trade-offs between economic incentives, environmental motivations, and mobility-related impacts. Using a governance-oriented interpretation of survey data, the analysis highlights how different incentive structures activate heterogeneous crowdshipper participation patterns, with distinct mobility impacts. Results show that participation driven by strong economic incentives and operational flexibility may encourage additional vehicle-kilometers traveled, while participation embedded within routine trips and influenced by environmental considerations tends to operate within more limited spatial and temporal constraints. Taken together, these findings indicate that crowdshipping outcomes are not inherently aligned with sustainable urban mobility objectives, but critically depend on incentive design and regulatory integration within Sustainable Urban Mobility Plans (SUMPs).

Comi, Antonio, Idone, Ippolita

Understanding Tyre Wear Particle Emissions: Volatile Dominance, Variability, Coarse Particles and Measurement System Development for Chassis Dynamometer Use

2026-24-0018

9/21/2026

This paper presents a set of targeted tyre emissions studies carried out within the UK Department for Transport’s (DfT) Brake and Tyre Emissions programme. The work was aimed at improving the measurement of airborne particles generated by tyres, and at examining the factors that influence particle number and particle mass emission. It also explored physical tread wear. To achieve this, a revised sampling duct system was developed with high extraction flow and partial wrap-around of the tyre, and a coarse hard-wearing surface was applied to the chassis dyno roller. The sampling system supplied Total PN4, PN10 (volatile and non-volatile), PM2.5, and particle size instrumentation. Several tyre types were selected to represent a broad range of sizes, constructions, manufacturers, compounds, and mileages. Tests were performed on a dedicated chassis dynamometer testing facility using PG42, WLTC, and RDE based cycles, together with additional cycles designed to investigate the influence of temperature, speed, and braking. Tread depth and tyre mass were recorded before and after the test programme to determine wear rates, and macro particle sampling was undertaken to assess particle size distribution beyond the airborne PM2.5 range. Airborne particle measurements showed that tyre PN is dominated by volatile ultrafine particles below 10 nm, with the non-volatile PN10 fraction representing only a small proportion of the total. PM2.5 mass from tyres was generally low and often near the detection limit, with most of the physical wear mass present as large particles (>50 μm) rather than as respirable material. Wear rates varied across tyres but showed no consistent relationship with airborne PM2.5 or PN10. Tyre temperature had the clearest influence on airborne PN emissions: elevated temperatures and high speed/braking conditions produced higher volatile and non-volatile PN. Overall, the study provides improved understanding of tyre-related airborne particle formation, the limitations of PM2.5 and PN10 as regulatory indicators, and the role of tyre temperature and operating conditions in determining emissions. The findings support the development of future tyre wear measurement methods and associated regulatory frameworks.

Andersson, Jon, Campbell, Michael, de Vries, Simon, Kramer, Louisa, Marshall, Ian, Southgate, Jason, Waite, Gary

A Life Prediction-Driven Maintenance Decision Method for Aircraft Engines

2026-99-1406

9/11/2026

As the operating conditions of aircraft engines become more complex, the traditional maintenance strategies based on experience or fixed cycles are difficult to balance economic efficiency and reliability. This paper tentatively proposes a maintenance decision-making method driven by life prediction for aircraft engines. In the life prediction stage, considering the complex spatio-temporal coupling relationships contained in the degradation signals of multiple sensors, a spatio-temporal feature fusion transformation network is designed to jointly model the spatial dependence and temporal dynamics. At the same time, a probabilistic deep learning model is introduced to model the mean and uncertainty of the remaining life, providing risk warnings beyond point estimation. In the maintenance decision-making stage, the predicted distribution parameters are introduced into the Markov decision process state space. Based on the deep Q-network, a reward function is designed, and cost constraints are considered, thereby achieving a balance between safety and economy. Experimental results based on the C-MAPSS dataset show that this method achieves reasonable performance in common prediction indicators and demonstrates certain advantages over traditional maintenance strategies in the comparison experiments of maintenance decisions. The effectiveness of the method has been verified.

Yu, Sijia

Optimization of Order Picking in an AMR-Assisted Picker-to-Parts System

2026-99-1567

9/11/2026

With global retail sales expanding and same-day delivery demand on the rise, efficient order picking operations in warehouses have become critical to success. To improve order picking processes, warehouse managers increasingly rely on autonomous mobile robots (AMRs), which improve the performance of traditional picker-to-parts systems. This paper investigates an AMR-assisted picker-to-parts system in which a set of customer orders must be fulfilled. The orders are first batched, and the resulting batches are assigned to individual pickers. Each picker works in a batch-by-batch manner, manually retrieving items from picking aisles and handing over the completed batch to an AMR waiting at the cross aisle. After receiving a full batch, the AMR transports it to the designated depot before returning to serve the next batch. The objective is the minimization of the total tardiness of all orders. The problem is formulated as a mixed-integer programming (MIP) model, and several effective heuristic algorithms are developed. Extensive computational experiments are conducted to evaluate the performance of the proposed algorithms and compare them with a commercial MIP solver.

Jin, Bo, Peng, Jianxin

Research on the Application of Multi-Source Data in Bus Route Network Optimization

2026-99-1566

9/11/2026

This research aims to optimize the bus route network in Shiyan City using bus Origin-Destination (OD) data. By integrating multi-source data, including GDP, population, and bus OD big data from 2018 to 2022, short-term and long-term indicators are forecasted by time-series methods. Shiyan city is divided into 77 Traffic Analysis Zones (TAZs) considering its mountainous terrain, population-industry distribution, and urban planning. A conventional four-stage traffic demand model is applied, calibrated with bus OD data in 2021. The investigation reveals peak-hour bus passenger travel demand of 29,700 short-term and 31,800 long-term person-trips in the city center and key corridors. Bus passenger travel forms a four-vertical and five-horizontal layout in the short term, evolving to a five-vertical, five-horizontal, and two wings pattern in the long term with eastward urban expansion. Accordingly, an optimized and upgraded bus route improvement strategy is devised. In the short term, there are seventy existing bus routes that are adjusted, creating a five-layer bus route network with diverse functions. Long-term plans involve optimizing twenty bus routes and adding eight new routes to align with urban development. This research not only aids an integrated bus route network optimization framework using bus OD data in a time-consuming way, but also provides a sample of bus route network adjustment for a typical mountainous city.

Ye, Qian, Chang, Sheng, Shen, Yucan, Li, Tanfeng, Tian, He, Tian, Shimo, Cen, Jian

Ultrasonic Frequency-Domain Reverse-Time Migration Imaging Incorporating Element Directivity Correction

2026-99-1419

9/11/2026

The finite width of ultrasonic array elements results in a non-uniform angular radiation pattern of elastic waves in solids, deviating from the ideal point-source assumption commonly adopted in reverse-time migration (RTM). This angular radiation non-uniformity produces a crack tip-dominated imaging amplitude with weak crack flank representation, manifesting as a pronounced depth-dependent amplitude imbalance along vertically oriented defects. As a result, cracks may be misinterpreted as point reflectors, which compromises the reliability of characterization in ultrasonic nondestructive testing (NDT). This study proposes an ultrasonic frequency-domain reverse-time migration (FDRTM) imaging method incorporating element directivity correction. A longitudinal-wave directivity model in solids is formulated in the frequency domain and normalized at each frequency to ensure consistent scaling during multi-frequency stacking. During backward wavefield reconstruction using full matrix capture (FMC) data, the angular-dependent energy distribution associated with the receiving direction is explicitly corrected, rebalancing the angular energy distribution in the reconstructed wavefield. Defect imaging is then performed using a frequency-domain cross-correlation imaging condition, followed by stacking over frequency and normalization. Validation experiments were conducted on an artificially manufactured vertical crack in a 7075 aluminum alloy specimen. The results indicate that, relative to conventional RTM, the proposed method reduces crack tip dominance and enhances the relative visibility and continuity of crack flanks. Compared with conventional RTM, the peak imaging amplitude increases by 22.44%, and the amplitude at a depth of 6.8 mm is enhanced by 24.39%. In addition, the proposed method outperforms the total focusing method (TFM) in crack profile continuity and the relative visibility of crack flanks. The results confirm that incorporating element directivity correction into frequency-domain RTM mitigates depth-dependent amplitude imbalance and restores crack flank visibility, thereby improving the reliability of crack defect characterization in ultrasonic NDT.

Chen, Si, Zhang, Yifeng, Ma, Tengfei, Xu, Zheng, Jiang, Jiansheng, Gao, Jiaqi

Safety-Aware Path Planning for Unmanned Surface Vehicle: An Adaptive Hybrid Collision Avoidance Operation

2026-99-1524

9/11/2026

An adaptive performance-enhanced path planning algorithm is proposed for unmanned surface vehicle (USV) to improve their responsiveness in dynamic maritime environments. The improved ant colony (ACO) algorithm incorporates a pheromone penalty mechanism and path smoothing to enhance search efficiency and path smoothness by removing redundant nodes and reducing excessive turning. Additionally, the dynamic window approach (DWA) is enhanced through three key modifications: optimizing overshoot, enhancing selection efficiency in candidate path, and adaptively adjusting evaluation function weights. These improvements improve the accuracy of planning and avoidance ability. Comparative analysis based on simulation data indicates that the proposed method yields a measurable improvement in path quality—characterized by reduced travel length and enhanced collision avoidance—leading to more robust navigation performance in complex marine transportation scenarios.

Sun, Jiamian, Li, Weifeng

Real-Time Spatiotemporal Correlation Feature Analysis of Traffic Flow Based on CEEMD+BiGRU Combination Model

2026-99-1555

9/11/2026

In the application process of real-time traffic flow data, the main reason affecting the analysis of spatiotemporal correlation features is the overlapping distribution of its own characteristic modes, which leads to poor representation of spatiotemporal features and the problem of inability to fit traffic flow with true values, failing to meet the requirements of confidence interval distribution. This paper proposes a CEEMD BiGRU combination model and uses the IMF components obtained by decomposing traffic flow data into CEEMD to represent spatiotemporal properties. A bidirectional time series model is constructed using BiGRU, and multi-scale features are used as inputs to fit traffic flow and true values. By bidirectionally calculating the hidden states of multi-scale features and considering the distribution requirements of confidence intervals, the spatiotemporal dependencies related to traffic flow are correlated and output. The case shows that the output flow of this method is highly consistent with the true value, which can improve the accuracy of prediction.

Gao, Bowen, Gu, Feifei

Study on Water Hammer Effect of an Aircraft Composite Fuel Tank under High-Speed Impact of Multiple Fragments

2026-99-1420

9/11/2026

The investigation examines the damage mechanisms of composite fuel tanks under high-speed impact by multiple fragments utilizing a fluid-solid coupling finite element approach. The Arbitrary Lagrangian Eulerian (ALE) algorithm is used to simulate the single-box composite fuel tank under the impact of different distribution distances of fragments by using the software LS-DYNA. The cavity evolution and the panel deformation of the composite fuel tank are analyzed in detail. The findings indicate that the water hammer effect amplifies the extent of damage to the composite fuel tank structure. During the initial phase following fragment impact, a cavity forms within the tank. The resulting rise in the pressure difference between the interior and exterior of the tank causes the liquid to impinge on the impacted panel, leading to its deformation. In the later stage, due to the large degree of damage to the incident panel, there is a certain degree of pressure relief inside the fuel tank, the degree of water hammer effect is obviously reduced, and the cavity in the fuel tank gradually disappears. The distribution distance of the fragments has a great influence on the damage effect of the fuel tank. As the spacing between fragments diminishes, their effects become more concentrated. This results in increased force from the liquid on the fuel tank panel, leading to greater deformation and more severe damage to the panel.

Wang, Ruiwen, Song, Yahui, Li, Chengwang

Study on Shaking Table Model Test of Seismic Dynamic Response of Loess Multi-Arch Tunnels

2026-99-1584

9/11/2026

Taking the Nieye Multi-Arch Tunnel in Zhuoni County as the engineering background, this study systematically explores the seismic dynamic response characteristics of loess multi-arch tunnels through shaking table model tests. The test results show that: (1) The strain distribution of the surrounding rock is significantly different. Under a peak acceleration of 0.6 g, the maximum strain in the tunnel portal section is concentrated on the right side, which is related to the incident direction of seismic waves and the stress concentration at the bottom of the central wall; the maximum strain in the tunnel body section is located on the left side, affected by the propagation characteristics of seismic waves, burial depth, and unsymmetrical pressure. (2) The acceleration amplification factors in the Z and ZX directions show nonlinear changes. Under bidirectional excitation, the Wenchuan wave-ZX combination exhibits the strongest response. The variation trend of acceleration at the soil-rock interface varies with wave types, and the slope damage undergoes three stages: elastic stage, elastoplastic stage, and plastic damage stage. (3) The ratio ω of tunnel burial depth to central wall thickness is positively correlated with the strains at key positions. For the seismic design of loess multi-arch tunnels, special attention should be paid to sensitive areas such as the bottom of the central wall and the left side of the tunnel body. It is suggested to improve the structural seismic performance by optimizing the lining reinforcement and adapting to regional seismic wave types. The research conclusions provide a reference for the seismic design of such tunnels under complex geological conditions.

Han, Tao, Cao, Xiaoping, Zhang, Shulin, Yang, Zibin

2025 5th International Conference on Logistics System, Traffic and Transportation (LSTT 2025)

2026-99-1500

9/11/2026

TOC

Tobolski, Sue

Linkages and Propagation Mechanisms of Risk Sources during Electric Vehicles Transportation

2026-99-1528

9/11/2026

This study addresses safety issues in three representative logistics scenarios for electric vehicles (EVs) as cargo-car carriers, roll-on/roll-off (Ro-Ro) vessels, and containers. To address the heterogeneity across these modes, we develop an integrated “process–spatiotemporal load–risk factor” framework that embeds operational steps and confinement conditions into the indicator system, overcoming the limitations of single-scenario or single-factor studies in explaining chain-type propagation. Building on process mapping and spatiotemporal load characteristics, we develop a risk indicator system spanning “person-equipment-transported object-operation & environment-system management.” Expert judgments are then analyzed using an integrated DEMATEL-ISM approach to quantify inter-factor linkages and transmission pathways. The results indicate that regulatory oversight and carrier-side emergency equipment constitute the deep root causes of thermal runaway. The most hazardous transmission route is “regulatory oversight, procedural compliance and skill-experience match”, while “battery type, road/sea conditions and hoisting impacts” forms the shortest path. These findings reveal weaknesses in management and equipment that are amplified by operational execution and limited personnel capability, ultimately precipitating severe transportation incidents.

Yuan, Libo, Jiang, Huifu, Qin, Xiao

Research on Location Selection of Logistics UAV Takeoff and Landing Points for Uncertain Demands

2026-99-1579

9/11/2026

In order to solve the problem of sharp fluctuations in demand in the terminal delivery of logistics drones and the situation that traditional positioning models lack robustness, this paper puts forward a robust positioning model (RFL-LU) that takes into consideration the demand uncertainties and the physical constraints of drones (such as endurance and no-fly zones, and so on). This model aims at minimizing the total cost of construction, transportation, and maintenance, and also combines the advantages of the set covering model and the P - median model. It incorporates an uncertainty budget Γ to adjust the degree of robustness, and then transforms the nonlinear robust constraints into linear ones through dual transformation, ensuring that the capacity of the take - off and landing points can cover both the nominal demand and the fluctuating increment. In order to efficiently address the model issues, an improved tabu search (ITS) algorithm that we have developed is presented. This algorithm, which makes use of adaptive neighborhood operations, double-objective taboo lists, and elite solution crossover learning methods, optimizes the 0 - 1 position assignment variables and continuous capacity variables in two phases. We carried out simulations with LRP standard instances and made comparative verifications under different uncertainty budgets Γ (3, 6, 9, 12), and demand fluctuation ranges (from 30% to 80%), and also carried out sensitivity analysis at the same time. The results show that the uncertainty budget Γ has a rather significant impact on the number of take-off and landing points and load balancing: a high Γ can ensure a 100% service level, but the construction cost will be higher. There is a non - monotonic positive correlation between the demand fluctuation range and the total cost, and this model can balance costs and services by adaptively adjusting the scale of facilities. In this research, in the situation of uncertain demands, it offers the scientific decision-making basis for the layout of the take-off and landing points of logistics drones, and also enhances the network’s elastic and adaptive capabilities.

Ding, Zihao, Li, Xiaojin

Research on Heavy-Haul Train Operation Adjustment Considering the Degree of Chaos in Train Timetable

2026-99-1522

9/11/2026

Heavy-haul railway development is as important a strategic direction for China’s railway sector as high-speed railway development. With the continuous expansion of heavy-haul railway operational mileage and the growing transportation demand, the complexity of operational adjustment in heavy-haul railways continues to escalate. The operational adjustment for heavy-haul trains subjected to speed restrictions following maintenance windows, aimed at maximizing the restoration of timetable regularity and guaranteeing freight volume, constitutes a critical and urgent research problem. Grounding on the operational principle of heavy-haul railways that prioritizes freight volume preservation over strict punctuality, this paper proposes a rescheduling model that incorporates the timetable disruption level. By adopting the order entropy theory, the model is formulated to minimize the total system disruption level and freight time cost, thereby framing the rescheduling problem as an order entropy optimization problem. The train disruption level is a metric that quantifies the perturbation intensity of a rescheduled timetable relative to the original operational plan within a given railway section. By initializing the entropy value of the pristine operational order to zero, any subsequent entropy variation directly facilitates a systematic investigation into the evolution of train operational order. Effective timetable adjustment strategies are subsequently derived, contingent upon the available buffer time and freight volume constraints. Guided by actual operational timetables and sectional line characteristics, this research designs a case study. The Gurobi solver is employed to obtain a rescheduled heavy-haul train timetable that successfully restores the original freight volume. The proposed methodology contributes to the enrichment of railway transportation organization theory and provides robust decision-making support for the strategic deployment of heavy-haul train services.

Fu, Lu, Lin, Li, Xu, Shichao, Ji, Guanggang, Li, Zheng

Impact of Transient Driving Characteristics on Bench-to-Road Emission Consistency of Light-Duty Vehicles

2026-99-1573

9/11/2026

The thalweg at the outlet of the Yuxikou Waterway transitions from right to left, forming a 90-degree bend. It then merges with the Xihua Waterway after passing Xiliang Mountain, creating a main-branch confluence water area. Taking a typical main-branch confluence water area in the lower reaches of the Yangtze River as the research object, this paper reflects the current navigation status and existing problems of ships in the area through the analysis of ship traffic flow. It classifies the risk levels of passing ships, proposes suggestions for route reform and optimization, and uses a model to verify the probability of collision accidents in the area after the implementation of the round-island navigation method, providing a reference for the navigation safety of passing ships.

Qiao, Jiajun, Jin, Zhenhua, Huang, Qi, Li, Guohui, Zhang, Xinguo

Experimental Study on Partitioned Fruit and Vegetable Storage in Ships

2026-99-1503

9/11/2026

After an investigation into a fruit and vegetable storage compartment on a ship, this paper proposes a method for creating different temperature zones within a single storage unit. To perform this approach, a top perforated plate air supply system should be implemented, and storage panels should act as partitions to make temperature control more accurate in different zones within the same compartment. This method ensures that fruits and vegetables can be stored for the best flavor at suitable temperatures, enabling fewer separate storage units on the ship. According to the experimental results, this solution can preserve various types of fruits and vegetables under different conditions during long trips, deal with the challenge of chilling or freezing injury due to mixed storage, and save the cold storage capacity on the ship. The proposed method has significant value in engineering applications.

Xie, Zhihao, Cui, Yonglong, Duan, Wenli, Li, Kun, Li, Qi, Wei, Shuaiju

Research on Torque Allocation Control of Multi-Articulated Vehicle

2026-99-1123

9/11/2026

The multi-articulated vehicle uses distributed drive mode. Due to its large degree of freedom of movement and the large number of driving shafts, different torque distribution methods affect the operational stability of the vehicle, how to coordinate and distribute the torque of each driving motor has become an urgent problem to be solved. To improve drive stability of the multi-articulated vehicles, propose a layered torque allocation control strategy. The upper-layer sliding mode controller determines the required additional yaw moments of each car body based on the linear reference model, the controller is characterized by swift response and a strong ability to resist interference. The lower-level allocation module comprehensively considers the torque output limitations of the electric hub motors, the prevailing road adhesion state, and the corrective yaw moment constraints given by the upper layer, and constructs an optimization objective function centered on the uniformity and stability of tire load. The optimal distribution of driving forces for each wheel is completed by solving this function dynamically. To validate the strategy's effectiveness, a vehicle dynamics model is built in the multi-body dynamics software ADAMS/View. Using a joint simulation framework integrating ADAMS/View and MATLAB®/Simulink, the effect of the layered control strategy is evaluated in comparative simulation with uncontrolled situation under U-turn and single lane change conditions. The simulation outcomes demonstrate that, compared to uncontrolled situation, the yaw rate deviation of each car body under the torque layered control are significantly reduced, and the adhesion utilization rate of tire is also effectively controlled, thereby the driving stability is improved.

An, Guanbo, Zhang, Liwei

Research on a Brake Energy Recovery Strategy Based on Improved ANFIS

2026-99-1134

9/11/2026

This paper addresses the issue of regenerative braking energy recovery in new energy vehicles and designs and optimizes a braking force distribution strategy. The strategy uses an ANFIS controller to dynamically optimize the proportion of front-axle regenerative braking force. The introduction of a pruning algorithm reduces computational complexity, thereby enabling a significant increase in mileage while maintaining stable driving performance. Co- simulations integrating Simulink and AVL Cruise, alongside Hardware-in-the-Loop (HiL) tests, the proof is that this strategy can still maintain excellent stability under different braking intensities. Moreover, it exhibits significantly higher energy recovery efficiency compared to benchmark strategies, while its effectiveness and real- time performance are successfully validated.

Lin, Hui, Zhao, Xuezhan, Tian, Jiahao

An Improved Genetic Algorithm for Multimodal Hinterland Empty Container Repositioning Considering Demurrage and Detention charges

2026-99-1527

9/11/2026

The imbalance of global trade exacerbates the mismatch between supply and demand of empty containers, requiring rapid repositioning from import to export regions, so empty container repositioning has long been a focus of research. Compared to maritime repositioning, hinterland empty container repositioning is more complex because it occurs over a sophisticated multimodal transport network. Rail and inland waterways typically offer high capacity at lower cost, and hinterland container operators often consolidate containers and move them in batches to achieve economies of scale. In addition, demurrage and detention (D&D) charges, imposed on operators for delayed container returns, have remained high in recent years. Traditional hinterland empty container repositioning approaches that focus solely on transportation costs often overlook these time-related penalties, leading to higher total repositioning costs. To address this, we first develop a generic hinterland empty container repositioning optimization model that integrates both transportation costs and demurrage and detention charges while capturing batch-based dispatching characteristics observed in practice. Second, due to the model’s non-convex and combinatorial nature, traditional solvers struggle to provide efficient solutions. We further develop an improved genetic algorithm (GA) to solve this non-convex MINLP problem. The results of numerical experiments showcase the benign performance of our improved GA. Finally, we conduct a real-world case study based on a 2025 operation in China. The results demonstrate that minimizing transportation costs alone results in higher total repositioning expenses, while jointly optimizing transportation and D&D costs leads to more balanced and cost-effective repositioning strategies. This highlights the practical necessity of incorporating D&D considerations into HECR decision.

Yu, Mingzhu, Yang, Haoran, Zhang, Lingge

A Simple and Efficient THINC Scheme for Multiphase Flow via Dominant-Material Selective Reconstruction

2026-99-1229

9/4/2026

Multiphase compressible flow problems are widespread in aviation, aerospace, transportation, military, and industrial fields, for instance, in underwater explosion bubble dynamics, fuel injection for hypersonic vehicles, liquid sloshing in propellant tanks, and supercavitating underwater vehicles. This paper proposes an improved THINC (Tangent of Hyperbola for Interface Capturing) method for multiphase flow simulations, based on a selective reconstruction strategy for the dominant material. The core of the strategy is to apply the THINC reconstruction exclusively to the material with the largest volume fraction within a multiphase mixed cell, which numerically governs the local interface evolution. The volume fractions of non-dominant materials are then obtained through a proportional distribution that inherently ensures the summation (Σαk = 1) and boundedness (0 ≤ αk> ≤ 1) constraints are met without explicit corrections. This approach reduces the number of THINC reconstructions for each time step in a multiphase mixed cell from Nm (the number of materials) to one, significantly simplifying the algorithm and lowering computational cost. It thereby avoids the error accumulation and complex renormalization procedures associated with conventional schemes that reconstruct all materials. While strictly maintaining volume fraction conservation, the proposed method preserves interface sharpness through the underlying THINC framework. The method is implemented in a diffuse-interface, multiphase Eulerian framework and validated with a series of challenging benchmarks, including shock-helium bubble interaction, triple-point problem, gas impact, and the more complex modified gas impact. Numerical results show that, compared with conventional multiphase THINC approaches that reconstruct every material, the proposed scheme can reduce CPU time by about 40.0% without compromising the accuracy of key physical quantities.

Wang, Wei, Zhong, Yanxu, Hu, Qinghua, Yang, Canqun

Strain Analysis of Buried Pipelines in Trench Models Crossing Strike-Slip Faults

2026-99-1280

9/4/2026

Long-distance buried pipelines are the core type in pipeline transportation; the technical indexes and requirements for protection are stricter. In the previous coupling model of pipe and soil, the in-situ soil and backfill soil are treated as a unified continuous medium, and the actual geometric shape and boundary effect of the pipe trench are ignored through simplification of the calculation model. In this study, a new coupling model of in-situ soil, backfill soil, and pipeline is proposed to analyze the actual strain state of buried pipeline with different backfill soil and in-situ soil materials. A model was established based on the ANSYS software to simulate and investigate the mechanical behavior of strike-slip fault-crossing buried pipelines under real trench conditions. By varying multiple parameters, this study analyzes the effects of different operating conditions on the strain distribution and magnitude of buried pipelines. The findings of this study can serve as a reference for the design, construction, and protection of buried pipelines traversing active faults.

Li, Yuxiang, Wang, Guang, Zhang, Chengbin, Wang, Ke, Bi, Haisheng

Research on the Evaluation of Uncertainty in Roundness Measurement

2026-99-1244

9/4/2026

Accurate evaluation of measurement uncertainty is crucial for precision manufacturing. This paper proposes a two-stage Bayesian-Monte Carlo method for assessing roundness measurement uncertainty in online inspection. The method separates machining errors from measurement system errors by first establishing a prior distribution via calibration with a standard artifact and then updating it with workpiece measurements. To validate the method, measurements were conducted on a certified roundness standard, showing close agreement with the reference value. The method demonstrates effective uncertainty quantification with small sample sizes and provides a foundation for intelligent evaluation in dimensional metrology.

Gu, Tingting, Qian, Xiaoming, Qian, Li

Optimal Design of the Driving Axle Housing of a Heavy-duty Automobile

2026-99-1225

9/4/2026

As one of the important freight modes, heavy trucks need a high- strength and high-reliability drive system to carry huge goods. Therefore, the drive axle housing, a key component, significantly influences the performance and service life of vehicles, and its design and optimization have high practical significance. Firstly, this study begins by creating a geometric model of the axle housing using SW and analyzes its stress distribution under four typical operational conditions. Through static analysis, it is concluded that the most critical operational conditions are the maximum deformation of 2.151 mm and the peak stress of 272.3 MPa; in the fatigue analysis of ANSYS Workbench, the minimum life is 820,000 times. Results from both static and fatigue assessments indicate that the initial axle housing design satisfies stiffness, strength, and fatigue requirements. There is a large margin in the structure, which has certain optimization space. Considering the most dangerous working condition, the response surface optimization module of ANSYS Workbench is used with the objective of mass reduction. Finally, the axle housing is reduced by 4.09 kg; the corresponding maximum deformation is 2.262 mm, meeting stiffness criteria, while the peak equivalent stress reaches 280.3 MPa, remaining below the material's yield strength. The minimum life is about 620,000 times, and the maximum fatigue life is 1 million times, which still meets the requirements of the vertical bending fatigue test. This lightweight redesign reduces material and manufacturing costs while maintaining the requirements for deformation, stress, and fatigue strength.

Zhao, Shenglian, Zhong, Weijie, Zhang, Jian

Numerical Simulation and Optimization Study of Direct-Fired Hot Blast Stove Based on Computational Fluid Dynamics

2026-99-1230

9/4/2026

Shantui Janeoo Machinery Co., Ltd developed a new direct-fired hot blast stove. However, experimental research was costly and failed to adequately capture the internal temperature distribution patterns. Therefore, computational fluid dynamics (CFD) was employed to conduct a numerical simulation of its three-dimensional model, analyzing its flow and heat transfer performance. The results indicated that the swirling cold air intake method caused local vortices and outlet backflow, leading to uneven temperature distribution. To address this issue, numerical simulation was used to investigate the influence of key geometric parameters on the stove’s performance. An improved design was proposed, and the performance differences between the optimized and original structures were compared and analyzed. The optimized hot blast stove showed a significant improvement in temperature distribution uniformity, with the outlet air temperature increasing by 59°C compared to the original structure.

Wu, Guoqing, Zhong, Wenzheng, Shen, Yuanlin, Chen, Ziyun

Control of Heat Treatment Deformation in Thin-Walled Pipe Fittings and Optimization of Turning Processes

2026-99-1300

9/4/2026

A certain component features an overall thin-walled structure with a wall thickness less than 1 mm, manufactured from high-strength martensitic precipitation-hardening steel. This part demands extremely stringent dimensional accuracy, with circumferential wall thickness variation not exceeding 0.006 mm, making it a typical high- precision thin-walled component. To ensure component performance and material utilization, the primary forming processes include spin forming, solution heat treatment, and multiple turning operations. During actual machining, martensitic precipitation-hardening steel exhibits significant microstructural stress relaxation and uneven cooling after solution heat treatment, leading to substantial part deformation. This makes it difficult to control subsequent machining dimensions within tolerance limits. Additionally, conventional clamping methods during multi-pass turning operations often cause uneven stress distribution on components during processing, frequently resulting in dimensional deviations that severely impact finished product yield rates. To address this challenge, this study systematically developed specialized tooling design and optimized turning processes tailored to the structural characteristics and deformation mechanisms of these thin-walled tube blanks. Simultaneously, a gap-free turning fixture with uniform expansion and clamping capabilities was developed. Combined with optimized machining parameters during the turning stage, this significantly improved stress distribution during processing, preventing further deformation caused by localized stress concentration. Test results indicate that after process optimization, the overall machining accuracy of this component improved by approximately 70% compared to the original process. Critical geometric tolerances showed significant enhancement, with roundness error consistently controlled within 0.30 mm and diameter dimensional consistency markedly improved. These measures not only successfully addressed deformation control challenges during heat treatment and machining of thin-walled parts but also provided a viable process solution and technical reference for precision manufacturing of similar high- difficulty, high-precision components.

Kou, Yue, Zhao, Honglian

Dynamic Modeling and Robust Active Control of Graphene-Piezoelectric Composite Missile Wings with Elastic Boundary Constraints

2026-99-1281

9/4/2026

To improve the stability and vibration suppression capability of missile wings under complex aerodynamic conditions, this study develops a dynamic model and explores the active control strategy for a graphene-reinforced piezoelectric composite missile wing subjected to elastic boundary constraints. An electromechanically coupled dynamic model with elastic boundary conditions is constructed by employing CLPT, the geometric nonlinearity following the von Karman assumptions, and piezoelectric coupling theory. The system is discretized and solved numerically using characteristic orthogonal polynomials and the Galerkin method. The influences of graphene distribution configurations, material properties, and boundary flexibility on the linear natural frequencies and nonlinear hardening characteristics are investigated. Results show that the X-type graphene distribution significantly enhances the equivalent stiffness and reduces nonlinearity. Boundary flexibility markedly modulates the vibration characteristics; in particular, increased structural flexibility strengthens geometric nonlinearity, leading to noticeable changes in frequency characteristics and hardening degree. A robust state-feedback controller together with a full-order observer is developed using the Linear Matrix Inequality (LMI) framework, and their performance is verified under different parameter disturbances and uncertainties. The control strategy effectively suppresses vibrations while maintaining good robustness, with the best performance achieved under X-type graphene reinforcement combined with thin piezoelectric layers. This study reveals the coupling mechanisms among material distribution, boundary flexibility, and robust control, providing a theoretical basis for the structural optimization and active control design of smart missile wings.

Qin, Shilong, Chen, Jie

Analysis of the Influence of the Centroid Distribution of the Raft on the Shafting Alignment

2026-99-0304

8/14/2026

Aiming at the problem of shaft alignment disturbed by the centroid distribution of the raft in the ship propulsion system, the quantitative influence of centroid offset on bearing load distribution and axis deformation is revealed. Based on the theory of an elastically supported continuous beam, the finite element model of the raft-shaft coupling system is established. By adjusting the position of the raft counterweight mass point (longitudinal offset range ±0.5 m) to simulate the centroid change, the static solution algorithm is used to analyze the key parameters, such as bearing load and axis alignment accuracy, under multiple groups of centroid offset conditions. It is concluded that when the centroid of the raft moves to the propeller end, the load of the 1# and 2# bearing near the propeller end increases, and the load of the 3# and 6# bearing near the thrust plate end decreases. The lateral offset of the center of mass increases, the axial offset at the stern bearing increases, the maximum deflection of the shafting increases, and the deformation of the raft structure increases. The centroid distribution of the raft is a disturbance source of the shafting alignment state, and its offset will reconstruct the bearing load distribution and cause the axis deformation. It is recommended to control the lateral offset of the center of mass at the design stage and reserve the dynamic compensation margin for the shafting alignment.

Yin, Hong, Jin, Yong, Wang, Jun, Tian, Jiabing

Measurement and Regulation of Residual Stress in Door Opening Welds of Wind Turbine Towers

2026-99-0197

7/31/2026

Weld residual stress is a critical factor affecting the structural integrity and service life of wind turbine towers. In this study, a systematic investigation was conducted on the residual stress distribution and control methods for door corner welds of an in-service wind turbine tower after approximately 20,000 hours of operation. X-ray diffraction (XRD) measurements revealed significant tensile residual stress in the weld and heat-affected zone, with peak values reaching 315 MPa, particularly concentrated at depths of 5-7 mm. To mitigate these stresses, two post-weld treatment methods were employed: ultrasonic impact treatment (UIT) and localized heat treatment. UIT effectively transformed surface tensile stress into compressive stress, achieving a maximum compressive residual stress of -372 MPa within a depth of 3 mm, while simultaneously refining grains and increasing surface hardness. In contrast, localized heat treatment at 460 °C for 5 hours led to a broader stress relief effect, reducing residual stress by approximately 100 MPa without causing significant changes to the macrostructure, but inducing substructural rearrangements beneficial for stress relaxation. Mechanical testing confirmed that both treatments improved tensile strength, ductility, and toughness of the welds. The combined findings demonstrate that ultrasonic impact treatment is highly effective for enhancing fatigue performance at the surface, while localized heat treatment offers advantages for deep stress redistribution and long-term structural stability. This comprehensive approach provides valuable technical guidance for residual stress management in complex welded structures of wind turbine towers.

Sun, Wanting, Zhong, Zhenqian, Zhang, Bo, Liu, Hui

Effects of Arrangement Patterns on Static Stability and Leakage Characteristics in Hybrid Labyrinth-Honeycomb Seals

2026-99-0166

7/31/2026

In this work, three-dimensional models of axial hole labyrinth-honeycomb seals (AHLHS) and circumferential hole labyrinth-honeycomb seals (CHLHS) were established by CFD to investigate the influence of different arrangement patterns on the static stability and leakage characteristics of two seals under choked and unchoked flow conditions and various eccentricities with different values. The results show that the two configurations have different advantageous ranges, and the hole arrangement pattern will not significantly change the pressure difference distribution between the two seals. Under most studied conditions, AHLHS maintains lower absolute values of stiffness coefficients, pressure difference groove, and negative cross-coupled stiffness coefficients, resulting in higher stability.

Li, Qing’an, Gao, Tongxin, Li, Zeze, Pang, Shuai, Lü, Yanjun, Zhang, Yongfang

Study on Stiffness Model of Bump Foil in Bump Foil Gas Bearings Based on Ansys Simulation Considering Axial Variable Loads

2026-99-0174

7/31/2026

To address the inaccuracy of existing models in describing the stiffness distribution along the axial direction of bump foils, this study first establishes a simulation model applicable to bump foils based on Ansys Workbench. Specifically, by applying axial variable load at a node that matches the distribution of actual operating conditions, the deformation and stiffness characteristics of the bump foil are investigated. The research results show that, compared with the classic Heshmat model, the bump foil stiffness is not uniformly distributed in the axial direction; instead, it exhibits a trend of being higher in the middle and lower at both ends. Notably, when the nominal stiffness values are similar, the axial end displacement obtained from the Ansys simulation differs significantly from the result calculated by the Heshmat model, with the deviation reaching up to 17.7% of the peak displacement from the latter. Furthermore, this study also systematically analyzes the influence of the laws of the bump foil’s curvature radius, length, and friction coefficient on its stiffness.

Wu, Yixuan, Shi, Yiming, Zhu, Jianjun, Liu, Jiajie

Discussion on Methods for Studying Material Fatigue Life: Taking Aluminum Alloy as An Example

2026-99-0121

7/31/2026

Fatigue design is a key common quality technology for improving the quality control capability of China’s automotive products. The fatigue of materials is a multi-scale damage evolution process. Characterizing and processing the large number of three-dimensional defects inside the material, which have different shapes and distributions, and predicting the material’s lifespan based on the cross-scale damage evolution mechanism, is one of the key technologies for fatigue optimization design. This paper discusses the research methods for the fatigue life of aluminum alloy materials. Firstly, based on the staged fatigue damage experiments, the three-dimensional defect features are obtained through CT scanning and reconstruction, and a defect characterization and processing method based on k-d tree and multi-scale feature pyramid is established to accurately represent the topological and geometric relationships of non-uniformly distributed three-dimensional defects. Secondly, a mathematical model for the evolution of micro-damage and macro-cracks is constructed, and the cross-scale transformation of defects is achieved through hierarchical and recursive methods, revealing the cross-scale evolution mechanism of fatigue damage in aluminum alloy materials. Finally, a remaining life prediction model based on defect information and feature weights is established through the support vector regression algorithm (SVR). This research method can provide technical support for the fatigue life optimization design application of lightweight materials such as aluminum alloys.

Zhang, Liangxia, Niu, Zhijun, Cheng, Fangfang, Chen, Hao, Yang, Yali

Design and Research of Robotic Arm for Belt Conveyor Roller Replacement

2026-99-0187

7/31/2026

To address the high failure rate of rollers in coal mine belt conveyors, the inefficiency of manual replacement, and the operational disruptions caused by maintenance shutdowns, this study proposes a robotic arm system capable of replacing rollers without halting conveyor operations. The research focuses on the kinematic performance and path planning strategy of the robotic arm. A kinematic model is established using the Denavit–Hartenberg (DH) parameters, and the workspace distribution is analyzed via the Monte Carlo method. The results show that the horizontal reach exceeds 2020 mm and the vertical reach extends up to 2000 mm, which fully satisfies the spatial requirements for roller replacement across the entire conveyor system. In the path planning phase, an obstacle expansion model is constructed, and an improved Informed RRT* algorithm is implemented to generate collision-free trajectories, ensuring effective obstacle avoidance. To improve trajectory smoothness, path pruning and cubic B-spline interpolation are applied to refine the initial paths. For trajectory planning in joint space, quintic polynomial interpolation is employed, with boundary conditions set to ensure zero velocity and zero acceleration at both the start and end points, thereby guaranteeing smooth and stable motion of the robotic arm. Simulation results indicate that joint angles, angular velocities, and angular accelerations vary smoothly throughout the roller grasping process, without abrupt changes, and converge to zero at the beginning and end of the trajectory. End-effector trajectory tracking error analysis reveals positioning errors within 0.8 mm for side rollers and 3 mm for central rollers, well within acceptable engineering accuracy thresholds. This work provides a theoretical foundation and a practical implementation framework for advancing automation and intelligent operation in roller replacement tasks within coal mine belt conveyor systems.

Pu, Congyuan, Qian, Ke

Ultrasonic Assisted Room Temperature Welding of Liquid Gallium Indium Alloy Brazing Material and Its Solidification Behavior at the Cu-Cu Interface

2026-99-0196

7/31/2026

Considerable the gallium-based alloys low melting point coupled with easy to synthesize intermetallic compounds with diverse metallic elements, employing liquid gallium-based alloys as the soldering medium and leveraging ultrasonic as assistance are effective to construct pure copper joints under atmosphere condition. The investigation delves into the characterization of the reaction products, interface microstructure, elemental distribution patterns, and evolution of shear strength within the welds. Furthermore, the pivotal role of ultrasonic waves and constituent element diffusion mechanisms during the solidification phase is elucidated. Thus, the initial one-day occurred during solidification showed the 2.6 MPa shear strength but with the time increased to four and a half days, the shear strength raised to 8.4 MPa at room temperature. Thereinto, the results indicate the weld seam has achieved metallurgical connection. This innovative welding technique operates at room temperature provides significant guidance for designing a novel perspective low-temperature joining for applications. It is not only augments the repertoire of material connection methodologies but also presents a viable joining strategy for sensitive elevated temperature materials. Therefore, such process possesses substantial practical significance and promises avenues for future applications.

Guo, Manying, Qu, Yingying, Fang, Qiuyue, Yang, Shen

Preparation and Characterization of Glycerol-Based Fe3O4 Magnetic Fluids

2026-99-0244

7/31/2026

To optimize the preparation protocol and tribological performance of glycerol-based Fe^3O^4 magnetic fluids, three hybrid agitation systems—(i) chemical co-precipitation coupled with magnetic stirring (H+C), (ii) chemical co-precipitation coupled with mechanical stirring (H+J), and (iii) chemical co-precipitation integrated with mechanical plus ultrasonic agitation (H+J+C)—were systematically investigated with respect to their influence on the physicochemical characteristics and lubricating behaviour of the resulting magnetic nanoparticles. Relative to the H+C and H+J protocols, the H+J+C protocol effectively suppressed intermediate agglomeration, yielding a 15 % increase in Fe^3O^4 productivity and a 15 % reduction in the full-width at half-maximum of the particle-size distribution. A binary surfactant system composed of oleic acid and citric acid achieved complete surface passivation, producing nanoparticles with a saturation magnetization of 59.2 emu g^–1. Under a magnetic flux density of 0.0341 T, tribometric evaluation revealed that the friction coefficient of the fluid prepared via the H+J+C route decreased to 0.041, corresponding to reductions of 7.1 % and 22 % relative to the H+J and H+C counterparts, respectively, thereby demonstrating superior tribological performance. The present work furnishes an experimental foundation for the rational design of high-performance magnetically responsive lubricants and the optimization of magnetic-fluid synthesis protocols.

Hu, Rui, Zhong, Shihao, Xu, Chunxia, Chen, Binhua, Liu, Yang

Pseudo-Label-Guided Dual-Supervised Alignment for Bearing Fault Diagnosis

2026-99-0233

7/31/2026

The inconsistency in bearing data distributions under diverse conditions often affects the representations of the faulty data and leads to indistinct decision boundaries and even negative transfer resulted from overlapping class distributions, greatly limiting the accuracy of the diagnosis model. To cope with the challenge, a pseudo-label-guided dual-supervised alignment (PDSA) method is developed for bearing fault diagnosis across diverse operating scenarios in this paper. To address the fixed alignment strategy issue, an adaptive distribution alignment layer is incorporated to ResNet18 to achieve dynamic data distribution alignment under varying condition, To enhance classification performances, a dual-supervised mechanism, comprising shallow-layer supervised contrastive learning is introduced through target domain pseudo-labels in target domain and deep-layer regularization class consistency. Experiments on two publicly available bearing datasets demonstrated this model realizes refined class-level alignment, strengthens fault states representation, and shows notable superiority in both accuracy and robustness.

Sun, Hao, Ren, Shijin, Gu, Zhangqing

Research on the Axial Assembly Stress and Fatigue Life of 60-Series Harmonic Reducers

2026-99-0191

7/31/2026

This study presents a systematic investigation into the assembly stress and fatigue life of 60-series harmonic reducers. A sophisticated finite element simulation model is constructed to precisely simulate the real assembly process and calculate stress distribution in the flexspline under axial assembly errors. In addition, corresponding fatigue life tests are designed to explore the influence of different axial assembly errors on the number of rotation cycles and transmission efficiency of the harmonic reducer. By comparing the predictions of the fatigue life mathematical model with the test data, a reliable fatigue life prediction method is established, providing a solid theoretical basis for the whole-machine assembly process and reliability design of this series of harmonic reducers.

Du, Yuefei, Qiu, Haodong, Fan, Yong, Li, Ziyuan, Dong, Yi, Zhang, Chi, Li, Chenzheng, Li, Yuan

The Protective Mechanism of Polyurea/Aramid Fiber Reinforced Steel Pipes against Implosion-Induced Multi-Physical Field Loads

2026-99-0135

7/31/2026

This paper studies the protective performance of polyurea-coated steel pipes and aramid fiber-wound steel pipes under the multi-physical field load of internal explosion by combining experiments with numerical simulation. The experimental results show that applying aramid fiber winding has a limited effect on improving the anti-explosion performance of steel pipes, while polyurea-coated steel pipes exhibit better anti-explosion performance under the coupled load of shock waves and fragments. Simulation analysis reveals the protective mechanism of composite structures in terms of energy absorption and stress distribution, providing a theoretical basis for the optimal design of blast-resistant vessels.

Tian, Xiangpeng, Wang, Tao, Bian, Xiaobing, Huang, Guangyan

Advancing Reliability Centered Maintenance: A Robust Statistical Approach for MTBF Estimation in Aero-Engine Fleets via Subgrouping Strategy and Dual Weibull Modeling

2026-99-0213

7/31/2026

Fleet heterogeneity, from manufacturing variations and diverse operating conditions, complicates reliability analysis by obscuring true failure patterns in aero-engines. This is a critical challenge in an industry as inaccurate Mean Time Between Failures (MTBF) estimates threaten safety and inflate operational costs, by forcing a choice between inefficiently conservative maintenance or the risk of in-service failures. Conventional analysis often fails by pooling all fleet data. To address this, our paper presents an analytical framework that improves predictive accuracy by filtering, rather than aggregating statistical noise. The methodology uses a Randomized Block Design (RBD) and ANOVA hypothesis test to screen a diverse dataset and isolate statistically homogeneous subgroups. This filtration identifies a core fleet with a consistent failure signature, providing a purified dataset for modeling. This refined data is then modeled using both Weibull and the Exponentiated Inverse Weibull distributions to ensure the results are robust and not model-dependent. Applying this framework to a 25-engine dataset that experienced 66 failures, we isolated a stable failure pattern, yielding a primary MTBF of 171.16 hours and a cross-validated MTBF of 176.35 hours. The close 3% convergence between these models validates our approach. By providing a dependable MTBF, this work establishes a stronger foundation for data-driven Reliability Centered Maintenance (RCM). It empowers maintenance planners to move toward evidence-based intervals, safely extending engine time-on-wing, optimizing spare parts inventory, and significantly reducing direct operational costs for airlines.

Jubaid, Mayin Uddin, Bebe, Gibson, Bigyen, Musa Pethuel, Anik, S M Kullul Mehedee, Yasmin, Ashrafi, Sahran, Mohamed Sideek Mohamed

Robotic Grinding Trajectory Planning and Correction Method for Large-Scale Complex-Shaped Products

2026-99-0227

7/31/2026

Due to the inherent characteristics of large dimensions, complex curved surfaces, and densely distributed protrusions present in aerospace products, conventional offline programming and trajectory planning techniques for robots primarily prioritize the facilitation of uninterrupted grinding processes and the generation of points along trajectories on surfaces characterized by smoothness. However, these methods encounter challenges in identifying and proactively avoiding surface protrusions during the planning phase. The present paper puts forth a proposal for an automated robot trajectory planning method for grinding operations. This method is predicated on the integration of region partitioning and deformation correction. Specifically, this method first identifies protrusions based on curvature features and rule matching, followed by an analysis of the feasible workspace of a six-axis industrial robot equipped with an external axis. The product surface is discretized into multiple regional units according to the distribution characteristics of protrusions and the constraints of the feasible workspace. Subsequently, a parameter-optimized parallel sectioning method is employed to independently plan trajectories for each unit. The utilization of on-site measured point cloud data facilitates the analysis of contour deviations. In addition, grinding trajectories are dynamically corrected to meet high-precision process requirements. This approach effectively overcomes the challenge that trajectory planning for large-scale, complex-shaped products is easily affected by protrusions. According to the established methodology, the development of an offline programming software system for robotic automatic grinding was initiated. To this end, experiments were conducted on aircraft wall panels to plan and modify grinding trajectories using the proposed method. This process was undertaken to validate the effectiveness and engineering practicability of the proposed method.

Fan, Changhao, Wang, Mingyang, Lv, Ruiqiang, Zhou, Peng

Construction of a Digital Management Platform for Intelligent Workshops in the Electronics Industry

2026-99-0117

7/31/2026

Under China’s intelligent manufacturing strategy, manufacturing enterprises are expected to achieve digital and networked operations by 2025, with full digital transformation by 2030. Intelligent factories, the core of this transformation, rely on interconnected, integrated, and data-fused systems. This paper focuses on the micro-assembly intelligent workshop at the Nanjing Research Institute of Electronics Technology, which produces micro-circuit modules for large-scale complex electronic systems. The workshop combines discrete and process manufacturing modes, presenting unique challenges for digital management. A digital management platform based on a five-layer architecture (device, network, data, application, and decision layers) is proposed to address multi-dimensional business needs, including production scheduling, logistics, execution, and decision optimization. A hierarchical workflow structure of the workshop, consisting of a main workflow and several sub-processes, is in-depth studied and designed. The platform is constructed based on requirements analysis and workflow design of the workshop and integrates systems such as MES, APS, WMS, and SCADA, supported by AI-driven big data analytics. This study offers a practical framework for advancing digital transformation in the electronics industry.

Zhang, Jian, Wang, Jiafeng, Guo, Yongzhao

Study on the Contact Stress Distribution and Calculation Method of Cylindrical Roller Bearings Considering Clearance Changes

2026-99-0124

7/31/2026

The distribution of contact stress in roller bearings has a significant impact on operational performance and safety. Firstly, we established a bearing clearance change model that combines interference fit and thermal expansion effects. Then, we studied the clearance changes of key parameters’ influence under different operating conditions. Using Hertz contact theory, we analyze the nonlinear coupling relationship between clearance changes, load distribution, and contact stress. Through MATLAB analytical calculations, load and stress distribution contour maps were obtained under typical operating conditions, which provided theoretical support for bearing optimization design and reliability analysis. The result depicts that an increase in interference fit and temperature difference leads to clearance decrease, triggering a redistribution of contact stress. As clearance decreases, the maximum contact stress exhibits a nonlinear growth trend. To further enhance engineering practicality, this paper uses the MATLAB platform to develop a visualization of digital image processing software. The software enables interactive analysis throughout the entire process of clearance input, stress calculation, and graphical display.

Pang, Yiqing, Cai, Hongbin, Ren, Siyang

Analytical Analysis of Wellbore Stresses under Fluid Pressure and In-Situ Stress in Three-Dimensional Wellbores

2026-99-0831

7/30/2026

During fluid injection operations such as fracturing and well killing, the casing, cement sheath, and borehole wall rock are subjected to three-dimensional in-situ stresses and internal pressure. If the equivalent stress exceeds the material’s yield strength, component failure may occur, leading to wellbore failure or even blowout accidents. In order to investigate the stress distribution in wellbores under specific working conditions, a three-dimensional mechanical model of curved wellbores was established. By adopting the superposition principle and stress function method, the influence of horizontal in-situ stress non-uniformity on the fourth equivalent stress of various components was analyzed. The study demonstrates that under three-dimensional in-situ stress, the fourth equivalent stress of each component increases with the rise of horizontal in-situ stress load non-uniformity and azimuth angle. Meanwhile, borehole azimuth angle and in-situ stress load non-uniformity exert a greater influence on the fourth equivalent stress of the casing, while internal pressure has a lesser impact on it. The effects of azimuth angle, horizontal in-situ stress load non-uniformity, and internal pressure on the fourth equivalent stress of the casing are more significant than those on the cement sheath and borehole wall rock. The research results can provide theoretical and technical references for wellbore design and safety improvement, as well as for the structural safety assessment of components such as automotive chassis and body frames under complex dynamic loads.

Zhang, Wenzhe, Jiang, Wu, Guo, Ziwang, Cao, Yinping, Dou, Yihua

Study on Particle Dispersion Mechanism of Ribbon-Type Composite Impeller Based on CFD-DEM

2026-99-0818

7/30/2026

For the solid-liquid mixing of hydroxy-terminated polybutadiene, which is a high-viscosity fluid with a viscosity of 3.5 Pa · s, and micron-sized silicon dioxide particles, this study employs the CFD-DEM numerical simulation method to analyze the solid-liquid mixing process of the ribbon-type composite impeller (RTC impeller). The stirring performance of the RTC impeller is investigated from perspectives including fluid flow field distribution and particle dispersion mechanism. The research results show that the main circulating flow generated by the RTC impeller generally exhibits a roughly symmetric distribution characteristic, and the flow pattern of the main circulating flow on both sides of the central structure is relatively balanced; however, there is a certain difference in the flow trend of the secondary circulating flow pattern on both sides of the central structure. The main circulating flow provides basic flow power for the secondary circulating flow, while the secondary circulating flow adjusts the local energy distribution through vortex motion. These two flows act synergistically to achieve an efficient solid-liquid mixing process.

Li, Ruizheng, Zhang, Yan, Sun, Zhenxing, Wu, Qiong

Construction and Verification of Munich EV Driving Cycle Considering Road Slope

2026-99-0869

7/30/2026

The driving cycle is the basic model of certification of vehicle fuel consumption and emissions, or calibration of powertrains. Standard regulatory driving cycles, such as WLTC, in general assume flat roads during their generation and fail to take into account the strong effect that road gradients have on vehicle operation and driving energy consumption. Such a shortcoming, then, leads to gross mismatches in adaptability when used for urban environments with typical hilly topography. To solve this problem, in this paper, we proposed a method for building driving cycles that consider the impact of slope with actual driving data. Initially, high-precision onboard data collectors were used to generate a total sum of 21, 350 km of driving data from the Munich area, thus creating a diversified driving data set with details such as vehicle speed, slope, and environmental information. Subsequently, joint probability distributions of “speed-acceleration” and “slope-slope change rate” are proposed by using the Micro-trip Method, and a novel chi-squared test algorithm is used to obtain a higher fidelity of urban driving cycle representative of typical conditions. Results of the driving cycle results show that the driving cycle built was close to the actual kinematics, indicating a deviation of less than 5%, and can capture the average uphill characteristic of 1.7%, which is quite well represented. Finally, in fact, validation of whole vehicle environmental chamber tests further demonstrates that the energy consumption prediction error of the developed driving cycle is just 2.2%, much lower than 19.1% error of WLTC. It highlights the importance of considering slope parameters in improving the accuracy of energy consumption calibration for an EV operating on complex slope terrains. Furthermore, it underscores that converting the real-world driving data into lab-based driving cycles can reduce the cost and time of actual road tests for Chinese companies going to the overseas markets, thereby offering support for the international marketing strategy of a global database.

Tian, Lichen, Jiang, Ping, Gao, Wang, Liang, Yongkai, Ma, Kunqi, Yu, Hanzhengnan

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