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To address the “anomalies” that occur when scientific breakthroughs emerge, this study focuses on identifying early signs and nascent stages of breakthrough innovations from the perspective of outliers, aiming to achieve early identification of scientific breakthroughs in papers.

Abstract The bogie is a critical component of high-velocity trains. As train velocity rises, the operational quality is increasingly influenced by aerodynamic forces. The aerodynamic characteristics of bogies significantly impact the safety of train operations. This article examines a real high-velocity train model, constructing a 3-group train model, and developing a mathematical model of high-velocity train operation on open lines. Using three-dimensional steady-state Navier–Stokes equations, the flow field characteristics, pressure spread, aerodynamic forces, and torque characteristics on the bogie and body of high-velocity locomotives operating at velocities of 200 km/h, 250 km/h, 300 km/h, and 350 km/h are calculated, with measurement spots set to study the trend of pressure variation with train velocity. The research findings indicate that pressure at the same location on the body surface rises with vehicle velocity, with a quadratic link between the two. The uneven pressure spread between two bogies of the same vehicle and between two axles of the same bogie indicates that aerodynamic forces can cause axle load transfer in high-velocity trains. The highest values of aerodynamic resistance and lift happen at the front bogie, and the resistance and lift of both a single carriage and the entire vehicle increase with velocity, following a quadratic relationship. The highest nodding torque of the train body occurs on one vehicle, while the highest nodding torque of the bogie occurs on the 6th bogie, with both torques increasing with velocity, also in a quadratic relationship.

Objective As the train operational speed increases, various braking methods become essential for ensuring high-speed train emergency safety braking. Wind resistance brakes, which complement wheel-rail adhesion brakes, have garnered extensive attention. The installation of wind resistance brake plates affects the train streamlined shape and can influence train operational safety under crosswind conditions. To ensure train operational safety and braking performance in high wind environments, it is necessary to thoroughly investigate the impact law of different brake plate configurations on train aerodynamic performance under crosswind conditions. Method Using three-dimensional, constant, incompressible Navier-Stokes equation and k-ε two-equation turbulence model, the influence of crosswind existence and varying brake plate heights on of high-speed train flow field and aerodynamic force are investigated. Result & Conclusion Simulation research results indicate that under crosswind conditions, the aerodynamic resistance on train carbody and brake plates increases along carbody direction, while the lateral force decreases. When the brake plate height increases from 0.5 m to 1 m, the proportion of brake plate resistance in overall resistance rises from 54.89% to 69.92%, with the maximum reaching 56 kN. The proportion of brake plate lateral force in overall lateral force is less than 1%, indicating that different brake plate heights have relatively little impact on train overall lateral force. The brake plates have a certain stopping effect on the incoming flow, and there is flow field interference between closely spaced brake plates. The influence of brake plates on lateral forces is minor. With proper preliminary design of brake plates, wind resistance brakes can be an effective train braking solution with minimal impact on train operational stability.

Abstract [Objective] The study aims to explore the effects of chemical fertilizer reduction and application of microbial fertilizers on growth and photosynthetic physiological characteristics of Lanzhou lily (Lilium davidii var. willmottiae), and to provide scientific fertilization management for continuous cropping of Lanzhou lily. [Methods] From 2019 to 2021, fertilization was applied in the experimental field of Lanzhou lily located in alpine humid area in Gansu Province. The studies set up three different treatments: 100% chemical fertilizers (control), chemical fertilizer reduction by 30% with microbial fertilizers, and chemical fertilizer reduction by 50% with microbial fertilizers. After three years of continuous fertilization, the changes of physiological indexes such as growth, photosynthetic characteristics, and antioxidant enzyme activity of Lanzhou lily were investigated. [Results] Compared with control, chemical fertilizer reduction by 30% and 50% with microbial fertilizers improved seedling index, photosynthetic characteristics, and antioxidant enzyme activities of Lanzhou lily to different degrees, with the treatment of fertilizer reduction by 30% with microbial fertilizers had the best effect. Under the treatment of fertilizer reduction by 30% with microbial fertilizers, plant height, stem thickness, leaf area, underground biomass, and seedling index were increased. The photosynthetic pigment content was increased. Maximum photochemical efficiency of PSⅡ, actual photochemical quantum efficiency, electron transfer rate increased, none photochemical quenching coefficient were decreased. The enzyme activity of the antioxidant (SOD, POD, CAT, APX) was increased. The content of osmoregulatory substances (proline, soluble protein) was increased. The content of malondialdehyde was decreased, and the root vitality was enhanced. [Conclusion] The treatment of fertilizer reduction by 30% with microbial fertilizers promotes the growth of Lanzhou lily, enhances leaf photosynthesis, improves protection enzyme activities and osmoregulatory substances, alleviates the degree of membrane lipid peroxide, and improves root vitality.This treatment effectively improves the cultivation environment of continuous cropping Lanzhou lily.

Objective The stray current generated during the operation of urban rail transit vehicles with rail backflow method will cause electrical corrosion to nearby metal objects, while the special rail return mode can solve such problems. It is necessary to comprehensively analyze the matching relationship between the backflow device of urban rail transit vehicles and the special rail. Method Based on the structural parameters of bogies, backflow devices, running rails and special rails of urban rail transit vehicles, as well as their suspension parameters and gauges, a vertical and horizontal dimensional chain analysis method is innovatively established by analyzing the structural matching characteristics between the backflow device and the special rail. The spatial size matching relationship between the vehicle backflow device and the special rail of an urban rail transit vehicle under six working conditions is checked. The vehicle dynamics simulation model with backflow device is established by SIMPACK simulation software. Whether the vertical contact pressure between vehicle backflow device and special rail is within a reasonable range during train operation is analyzed under four working conditions. Result & Conclusion The checking of the spatial size matching relationship between the vehicle backflow device and the special rail shows that partial structure of the backflow device needs to be adjusted. Simulation analysis verifies that the vertical contact pressure between the vehicle backflow device and the special rail is within a reasonable range.

Aeronautical electronic equipment, used for data collection during flight, is usually fixed to the nose radome using mounting brackets. The stiffness and first-order frequency performance of the mounting brackets is studied to avoid plastic deformation and resonance during flight, which is of great engineering significance for improving flight stability. The static strength and modal analysis of the mounting bracket under inertial load are conducted, and a sensitivity analysis method is used to determine the design variables of the installation bracket. With the goal of minimizing the total weight of the structure as the optimization objective, the thickness of each component of the bracket is optimized while ensuring the stiffness and first-order modal performance of the installation bracket. The vibration tests are conducted for the optimized installation bracket structure. The results show that the stiffness of the optimized installation bracket structure remains basically unchanged, the first-order frequency is increased by 18.09%, and the weight is reduced by 19.33%. The improved design can meet the equipment installation requirements.