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The purpose of this study is to analyze the corrosion behavior of 304SS in three kinds of solution, 3.5 per cent NaCl, 5 per cent H₂SO₄ and 1 M (1 mol/L) NaOH, using electrochemical noise.

Corrosion types and rates were characterized by spectrum and time-domain analysis. EN signals were evaluated using a novel method of phase space reconstruction and chaos theory. To evaluate the chaotic characteristics of corrosion systems, the delay time was obtained by the mutual information method and the embedding dimension was obtained by the average false neighbors method.

The varying degrees of chaos in the corrosion systems were indicated by positive largest Lyapunov exponents of the electrochemical potential noise.

The change of correlation dimension in three kinds of solution demonstrated significant differences, clearly differentiating various types of corrosion.

The purpose of this study is to investigate the influence of surface texture on the subsurface characteristics of contact interfaces under elastohydrodynamic lubrication condition. As a typical contact form of gears and bearings, the optimization of friction characteristics at the elastohydrodynamic lubrication (EHL) interface has attracted the attention of scholars. Laser surface texturing is a feasible optimization solution, but there have been concerns about whether the surface texture of high-pair parts will affect their fatigue life.

To examine the impact of texture preparation on the subsurface characteristics of high-pair interfaces under EHL conditions, a point contact EHL model is developed that takes into account the effect of textured surface topography. The pressure and thickness of the oil film are calculated as input parameters under different loads and entrainment velocities. The finite element method is used to simulate the impact of textures with varying diameters, densities and depths on the subsurface characteristics of the elastohydrodynamic interface. According to ISO 25178, analyze the relationship between 3D topography parameters and subsurface characteristics and study the trend of friction characteristics and subsurface characteristics based on the results of the ball on disc friction tests.

The outcomes suggest that under different rotational velocity and load conditions, the textured surfaces exhibit improved friction reduction effects; however, the creation of textures can result in significant subsurface plastic deformation and local peeling. The existence of texture makes the larger stress zone in the subsurface layer closer to the surface, leading to fatigue failure near the surface. Reasonable design parameters can help enhance the attributes of the subsurface. A smaller Sa and a Str greater than 0.5 can achieve ideal subsurface properties on the textured surface.

This paper investigates the influence of surface texture on the friction and subsurface characteristics of EHL interfaces and analyzes the impact of surface texture on interface contact performance while achieving lubrication improvement functional characteristics. The results provide theoretical support for the optimization design and functional regulation of surface texture in EHL interfaces.

The peer review history for this article is https://publons.com/publon/10.1108/ILT-10-2023-0324/

The purpose of this study is to ensure the safe use of carbon fiber composite pressure vessels in the nuclear industry environment.

This study investigated the degradation behaviors of carbon fiber reinforced composite (CFRP) using the specific corrosive media HF solution, with a focus on the damage to the surface epoxy layer. The degradation behaviors of CFRP in HF solution were examined by electrochemical methods and surface characterization, using HCl, NaCl and NaF solution for comparison.

The results showed that the specimen in HF solution will have a value of |Z|_0.01 Hz one order of magnitude lower, a substantially lower contact angle, more breakage of the surface epoxy and the stronger O─H peak and weaker C─O─C peak in the Fourier transform infrared spectrum, indicating severe hydrolytic damage to the surface epoxy.

The work focuses on the degradation damage to CFRP surface epoxy by specific corrosive media HF.

This article aims to predict the rapid track geometry change in the short term with a higher detection frequency, and realize the monitoring and maintenance of the railway state.

Firstly, the ABA data needs to be filtered to remove the DC component to reduce the drift due to integration. Secondly, the quadratic integration in frequency domain for concern components of the vertical and lateral ABA needs to be done. Thirdly, the displacement in lateral of the wheelset to rail needs to be calculated. Then the track alignment irregularity needs to be calculated by the integration of lateral ABA and the lateral displacement of the wheelset to rail.

By comparing with a commercial track geometry measurement system, the high-speed railway application results in different conditions, after removal of the influence of LDWR, identified that the proposed method can produce a satisfactory result.

This article helps realize detection of track irregularity on operating vehicle, reduce equipment production, installation and maintenance costs and improve detection density.

In order to solve the problem of inaccurate calculation of index weights, subjectivity and uncertainty of index assessment in the risk assessment process, this study aims to propose a scientific and reasonable centralized traffic control (CTC) system risk assessment method.

First, system-theoretic process analysis (STPA) is used to conduct risk analysis on the CTC system and constructs risk assessment indexes based on this analysis. Then, to enhance the accuracy of weight calculation, the fuzzy analytical hierarchy process (FAHP), fuzzy decision-making trial and evaluation laboratory (FDEMATEL) and entropy weight method are employed to calculate the subjective weight, relative weight and objective weight of each index. These three types of weights are combined using game theory to obtain the combined weight for each index. To reduce subjectivity and uncertainty in the assessment process, the backward cloud generator method is utilized to obtain the numerical character (NC) of the cloud model for each index. The NCs of the indexes are then weighted to derive the comprehensive cloud for risk assessment of the CTC system. This cloud model is used to obtain the CTC system's comprehensive risk assessment. The model's similarity measurement method gauges the likeness between the comprehensive risk assessment cloud and the risk standard cloud. Finally, this process yields the risk assessment results for the CTC system.

The cloud model can handle the subjectivity and fuzziness in the risk assessment process well. The cloud model-based risk assessment method was applied to the CTC system risk assessment of a railway group and achieved good results.

This study provides a cloud model-based method for risk assessment of CTC systems, which accurately calculates the weight of risk indexes and uses cloud models to reduce uncertainty and subjectivity in the assessment, achieving effective risk assessment of CTC systems. It can provide a reference and theoretical basis for risk management of the CTC system.

The three-axis simulator relies on the air film between the air bearing and the bearing seat to achieve weightlessness and the frictionless motion condition, which is essential for simulating the micro-disturbance torque of a satellite in outer space. However, at the beginning of the experiment, the disturbance torque caused by the misalignment between the center of gravity of the simulator and the center of rotation of the bearing is the most important factor restricting the use of the space three-axis simulator. In order to solve this problem, it is necessary to set the balance adjustment system on the simulator to compensate the disturbance torque caused by the eccentricity. The paper aims to discuss these issues.

In this paper, a study of L1 adaptive automatic balancing control method for micro satellite with motor without other actuators is proposed. L1 adaptive control algorithm adds the low-pass filter to the control law, which in a certain sense to reduce the high-frequency signal and speed up the response time of the controlled system. At the same time, by estimating the adaptive parameter uncertainty in object, the output error of the state predictor and the controlled object can be stabilized under Lyapunov condition, and the robustness of the system is also improved. The automatic balancing method of PID is also studied in this paper.

Through this automatic balancing mechanism, the gravity disturbance torque can be effectively reduced down to 10⁻⁶ Nm, and the automatic balancing time can be controlled within 7 s.

This paper introduces an automatic balancing mechanism. The experimental results show that the mechanism can greatly improve the convergence speed while guaranteeing the control accuracy, and ensuring the feasibility of the large angle maneuver of spacecraft three-axis simulator.

Advertisements facilitate certain emotions, subsequently influencing purchase intentions. Humor, as an influential way of information expression, is frequently used in ads to elicit emotions. Drawing upon literature on advertisement humor and new product purchase intention and the theory of planned behavior, the study proposes that humor stimulation in advertisements can affect consumers' new product purchase intentions, in which two process mechanisms, namely, emotional arousal and cognitive flexibility, play a mediating effect.

To test the assertions, the authors conduct three experimental studies. The authors' first study assesses the main effect between advertisement humor and purchase intentions. In the second study, the authors show the mediating effects of emotional pleasure, emotional arousal, and cognitive flexibility on the relationship between advertisement humor and purchase intentions. In the first two experiments, the authors study incremental new products. In the third study, the authors study the same mediating relationships for radically new products.

This study's results show consumers that watch humorous ads are more likely to choose new products than those who watch non-humorous ads (Study 1); compared with non-humorous ads, humorous ads can enhance emotional arousal, thus promoting cognitive flexibility and making consumers more inclined to choose new products (Study 2 and Study 3). That said, the authors find that these mediation effects are only partial.

This study's results have important implications for firms vying to enhance consumers' new product purchase intentions by deploying humorous ads.

The geomagnetic field vector is a function of the satellite’s position. The position and speed of the satellite can be determined by comparing the geomagnetic field vector measured by on board three-axis magnetometer with the standard value of the international geomagnetic field. The geomagnetic model has the disadvantages of uncertainty, low precision and long-term variability. Therefore, accuracy of autonomous navigation using the magnetometer is low. The purpose of this paper is to use the geomagnetic and sunlight information fusion algorithm to improve the orbit accuracy.

In this paper, an autonomous navigation method for low earth orbit satellite is studied by fusing geomagnetic and solar energy information. The algorithm selects the cosine value of the angle between the solar light vector and the geomagnetic vector, and the geomagnetic field intensity as observation. The Adaptive Unscented Kalman Filter (AUKF) filter is used to estimate the speed and position of the satellite, and the simulation research is carried out. This paper also made the same study using the UKF filter for comparison with the AUKF filter.

The algorithm of adding the sun direction vector information improves the positioning accuracy compared with the simple geomagnetic navigation, and the convergence and stability of the filter are better. The navigation error does not accumulate with time and has engineering application value. It also can be seen that AUKF filtering accuracy is better than UKF filtering accuracy.

Geomagnetic navigation is greatly affected by the accuracy of magnetometer. This paper does not consider the spacecraft’s environmental interference with magnetic sensors.

Magnetometers and solar sensors are common sensors for micro-satellites. Near-Earth satellite orbit has abundant geomagnetic field resources. Therefore, the algorithm will have higher engineering significance in the practical application of low orbit micro-satellites orbit determination.

This paper introduces a satellite autonomous navigation algorithm. The AUKF geomagnetic filter algorithm using sunlight information can obviously improve the navigation accuracy and meet the basic requirements of low orbit small satellite orbit determination.

Adaptive slicing is a key step in three-dimensional (3D) printing as it is closely related to the building time and the surface quality. This study aims to develop a novel adaptive slicing method based on ameliorative area ratio and accurate cusp height for 3D printing using stereolithography (STL) models.

The proposed method consists of two stages. In the first stage, the STL model is sliced with constant layer thickness, where an improved algorithm for generating active triangular patches, the list is developed to preprocess the model faster. In the second stage, the model is first divided into several blocks according to the number of contours, then an axis-aligned bounding box-based contour matching algorithm and a polygons intersection algorithm are given to compare the geometric information between several successive layers, which will determine whether these layers can be merged to one.

Several benchmarks are applied to verify this new method. Developed method has also been compared with the uniform slicing method and two existing adaptive slicing methods to demonstrate its effectiveness in slicing.

Compared with other methods, the method leads to fewer layers whilst keeping the geometric error within a given threshold. It demonstrates that the proposed slicing method can reach a trade-off between the building time and the surface quality.

This paper aims to study the effect of chloride concentration on the properties of passive film formed on Q235 steel in simulated concrete pore solutions.

Mott–Schottky analysis and electrochemical impedance spectroscopy were used to study the passive film of Q235 steel in simulated concrete pore solution. X-ray photoelectron spectroscopy was used to analyze the composition of passive film on Q235 steel.

When the chloride concentration is below the chloride threshold value, open circuit potential (OCP) and Rct gradually increases and donor concentration (N_D) remains unchanged with the increasing immersion time. When the chloride concentration exceeds chloride threshold value, OCP and Rct decreases after a temporary increase and N_D increases. The linear region of the Mott–Schottky curve lost its linearity. The electrochemical process control step is changed from charge transfer control to oxygen diffusion control. As the chloride concentration increases, the FeO content in the passive film increases and the Fe₂O₃ content decreases. Chloride can destroy the outer layer of passive film and introduce impurities.

The effects of chloride and immersion time on the change process of passive films on Q235 steel in simulated concrete pore solution were studied using electrochemical methods. The mechanism of chloride destroying passive film was analyzed.