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This paper aims to solve the typical thermal airflow sensor's high power consumption and integration difficulties, based on the FS5 thermal element and constant temperature measurement method, a flow sensor is developed with high measurement accuracy, low power consumption, small size, low cost and easy system integration.

A small wind tunnel was used to test and assess the sensor's measurement range, reaction time, stability, repeatability, measurement accuracy and multi-temperature calibration was performed in the temperature range of −10°C to 30°C. The effect of ambient temperature on the sensor's measurement data is investigated, and the coefficient correction method of power function was investigated to implement the sensor's software temperature compensation function.

The results show that the sensor is stable and repeatable, the output voltage has a power function relationship with the airflow rate, the flow rate measurement range is 0–18 m/s, the response time is less than 3 s, the measurement accuracy at high flow rates is within 0.4 m/s and the temperature-corrected airflow rate measurement error is less than 5%. Setting the temperature calibration interval to 2°C and 5°C has the same temperature compensation effect, reducing the sensor's calibration effort significantly.

This paper demonstrates that a thermostatic method is used to construct a thermal wind speed sensor that delivers accurate measurements in the wind speed measuring range of 0–18 m/s under test conditions. In addition, the sensor's performance is evaluated, and calibration tests for a wide range of temperatures are done. Finally, based on the power function correction method, a temperature compensation algorithm is proposed.

The shape of a product plays a crucial role in shaping consumer behavior. Despite the voluminous research on factors influencing consumers’ shape preferences, there remains a limited understanding of how the busy mindset, a mentality increasingly emphasized by marketing campaigns, works. This study aims to fill this gap by exploring the relationship between a busy mindset and the preference for angular-shaped versus circular-shaped products and brand logos.

This research consists of seven experimental studies using various shape stimuli, distinct manipulations of busy mindset, different assessments of shape preference and samples drawn from multiple countries.

The findings reveal that a busy mindset leads to a preference for angular shapes over circular ones by amplifying the need for uniqueness. In addition, these effects are attenuated when products are scarce.

This research represents one of the pioneering efforts to study the role of a busy mindset on consumers’ aesthetic preferences. Beyond yielding insights for practitioners into visual marketing, this research contributes to the theories on the busy mindset and shape preference.

Parallel factor analysis (PARAFAC) coupled with support-vector machine (SVM) was carried out to identify and discriminate between the fluorescence spectroscopies of coconut water brands.

PARAFAC was applied to reduce three-dimensional data of excitation emission matrix (EEM) to two-dimensional data. SVM was applied to discriminate between six commercial coconut water brands in this study. The three largest variation data from fluorescence spectroscopy were extracted using the PARAFAC method as the input data of SVM classifiers.

The discrimination results of the six commercial coconut water brands were achieved by three SVM methods (Ga-SVM, PSO-SVM and Grid-SVM). The best classification accuracies were 100.00%, 96.43% and 94.64% for the training set, test set and CV accuracy.

The above results indicate that fluorescence spectroscopy combined with PARAFAC and SVM methods proved to be a simple and rapid detection method for coconut water and perhaps other beverages.

The purpose of this paper is to assess the serious corrosion problems of the water injection system on the offshore oil field and to study the type, and effect factors and mechanisms of corrosion on the offshore oil field in order to develop an effective corrosion inhibitor for the sea water injection system.

The corrosion of metal in a water injection system was studied by weight‐loss and electrochemical methods.The effect factors and mechanisms of corrosion on the offshore oil field were proposed from the trend of corrosion.

FeCO₃ is the main corrosion product in the water injection system of the Chengdao Offshore Oil Field. The corrosion rate of coupons in sea water injection systems reaches a maximum peak at a temperature of 50‐60°C. The corrosion rate of coupons exposed in all three water samples increased with an increase in the dissolved oxygen concentration. When the mixed ratio of sea water and produced water and well water is 1:3:1 or 1:2:2, the corrosion rate of carbon steel is lower than is the case in pure water. The electrochemical mechanism of corrosion indicates that corrosion in the well water, produced water, and sea water samples were all controlled by the oxygen absorption process, which controlled the cathodic reaction. The corrosion rate of coupons followed the ranking order: well water; produced water; sea water.

This paper provides the main corrosion product in the water injection system of the Chengdao Offshore Oil Field, and provides new information on the effect factors and mechanisms of corrosion on the offshore oil field.

The purpose of this study is to develop a model extending Oriani’s formula by introducing a normalised concentration to simulate hydrogen diffusion in a multi-material system such as coated steels, under the presence of traps.

Implemented through the finite element method based on the analogy between mass diffusion and heat transfer, the governing equation was applied to investigate the combined effects of hydrogen traps and surface oxide films on hydrogen permeation in ferritic steels.

This study shows that the effective diffusivity varies over several orders of magnitude depending on the traps and films. This explains the divergence of measured hydrogen diffusivities in steels. It is revealed that hydrogen permeation in steels with Pd or Ni film is a trapping-dominant transport process, while hydrogen permeation in steel with oxide film is a process controlled by both trapping effect and retarding effect of oxide film. The oxide film enhances total hydrogen concentration within the steel substrate and is therefore detrimental. The Pd or Ni film has a little influence on total hydrogen concentration distribution depending on trapping energy.

Hydrogen flux curves and transient hydrogen concentration distributions can be directly obtained through the developed model. The proposed approach can also be extended to investigate other interstitial (i.e. carbon, oxygen and nitrogen) diffusion with traps revisited in complex systems.

This paper aims to examine the impact of host country corruption on foreign direct investment (FDI) from China to developing countries in Africa. With the opposing arguments that corruption is detrimental to or instrumental in FDI and mixed empirical evidence, this paper contributes to the literature by providing new evidence on the issue. Additionally, little research has been done on the impact of corruption on FDI made by developing country multinationals to developing countries. This paper fills a void in this area.

Based on the published literature, as well as China and Africa contexts, the authors develop hypotheses that host countries with low corruption receive more FDI and resource-seeking investments weaken the relationship. The annual stock of Chinese FDI in 35 African countries, host country corruption data and other control variables from 2007 to 2015 are collected. Feasible generalized least squares models are used to test the hypotheses. Additional robustness tests are also conducted.

The findings support the hypotheses. Specifically, Chinese investors make more investments in host countries with low corruption except for resource-seeking investments in resource-rich host counties. The results are statistically significant accounting for various control variables. The results of the robustness tests show that the main findings are robust.

First, this study provides new evidence on the impact of corruption on FDI. Second, this study also fills a void by examining FDI from a developing country, China to other developing countries in Africa. Finally, this study also has a practical implication for Chinese multinationals investing in Africa.

In this paper, an attempt is made to obtain buckling loads, ultimate bearing capacity and other required structural characteristics of grid structure panels. The numerical method for post-buckling behavior analysis of panels involving multiple invisible damages is also presented.

In this paper, two bidirectional stiffened composite panels are manufactured and tested. Multiple discrete invisible damages are introduced in different positions of the stringers, and the experimental and simulation investigation of buckling and post-buckling were carried out on the damaged stiffened panels.

The simulation load–displacement curves are compared with the experimental results, and it is found that the simulation model can well predict the occurrence of buckling and failure loads. The strain curve shows that the rate of strain change at the damaged site is greater than that at the undamaged site, which reflects that the debond is more likely occurred at the damaged site. The simulation verifies that the panel is usually crushed due to matrix compression and fiber–matrix shear.

In this paper, post-buckling tests and numerical simulations of bidirectional stiffened composite panels with impact damage were carried out. Two panels with four longitudinal stringers and two transverse stringers were manufactured and tested. The buckling and post-buckling characteristics of the grid structure are obtained, and the failure mechanism of the structure is explained. This is helpful for the design of wall panel structure.

Aiming at the problem of insufficient adaptability of robot motion planners under the diversity of end-effector constraints, this paper proposes Transformation Cross-sampling Framework (TC-Framework) that enables the planner to adapt to different end-effector constraints.

This work presents a standard constraint methodology for representing end-effector constraints as a collection of constraint primitives. The constraint primitives are merged sequentially into the planner, and a unified constraint input interface and constraint module are added to the standard sampling-based planner framework. This approach enables the realization of a generic planner framework that avoids the need to build separate planners for different end-effector constraints.

Simulation tests have demonstrated that the planner based on TC-framework can adapt to various end-effector constraints. Physical experiments have also confirmed that the framework can be used in real robotic systems to perform autonomous operational tasks. The framework’s strong compatibility with constraints allows for generalization to other tasks without modifying the scheduler, significantly reducing the difficulty of robot deployment in task-diverse scenarios.

This paper proposes a unified constraint method based on constraint primitives to enhance the sampling-based planner. The planner can now adapt to different end effector constraints by opening up the input interface for constraints. A series of simulation tests were conducted to evaluate the TC-Framework-based planner, which demonstrated its ability to adapt to various end-effector constraints. Tests on a physical experimental system show that the framework allows the robot to perform various operational tasks without requiring modifications to the planner. This enhances the value of robots for applications in fields with diverse tasks.

This study aims to construct a double layer heat insulation coating based on hollow glass microspheres (HGMs) and to investigate the effect of particle size on barrier property and heat insulation performance.

The waterborne double layer coating was composed of an anticorrosive epoxy ester primer and an HGM-containing silicone acrylic topcoat. With varied HGM sizes (20 μm, 40 μm, 60 μm and a 1:3 w/w mixture of 20 and 60 μm particles), the coating was immersed in 3.5 wt% NaCl solution for 28 days and was then subjected to a salt spray test for 450 h. The barrier properties of the coating were evaluated through electrochemical impedance spectroscopy. Heat insulation performance was examined using a self-made device.

The addition of HGMs decreased the barrier properties of the coating by creating particle/resin interfaces for water penetration. In the HGMs-containing coatings, the use of larger HGMs showed relatively good barrier properties because of the lower particle density. The coating with smaller particles yielded a higher heat insulating capacity as indicated by lower equilibrium temperatures.

Future work will be focused on improving the barrier properties of the coating. Field exposure tests should also be performed to assess the long-term performance of the coating.

The mechanical properties of the coatings in this study also implied that HGMs can be used to develop scratch-resistant and impact-resistant coatings. Other potential applications for further studies include the uses of HGMs for coatings with improved fire retardancy and electromagnetic interference shielding.

A double layer coating was developed to provide balanced performance on both anticorrosion and heat insulation. The effects of HGM size were particularly highlighted.