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Training activities organized by maker-spaces have become the most important channel through which makers acquire new external knowledge related to problem solving and thus contribute significantly to makers' innovation performance. Is it true that the more training activities in which makers participate, the better their innovation performance? Following the logic of process analyses, this paper empirically verifies the effects of the scope and frequency of makers' participation in training activities on their innovation performance.

Based on a survey of 134 makers in China, this paper employed the procedure recommended by Preacher and Hayes (2008) to empirically test the total effects, direct effects and indirect effects of the scope and frequency of participation in training activities on makers' innovation performance via their ability to exploit new knowledge.

The research findings show that the scope (frequency) of participation in training activities has a positive (negative) effect on makers' innovation performance via the mediating effect of the makers' ability to exploit new knowledge. Time pressure acts as a negative moderator.

This paper sheds light on a considerably overlooked research area by investigating the effects of the scope and frequency of makers' participation in training activities on their innovation performance. The authors further identify and empirically test the theoretical mechanism by considering the mediating effect of makers' ability to exploit new knowledge. The research findings also provide a managerial training activity arrangement strategy for makerspaces and government.

The purpose of this paper is to analyze the impact of paternalistic leadership on innovation.

This paper conceptualizes an integrated model that combines the dual‐core model and ambidextrous model of innovation. Using a sample of 159 Chinese high‐tech enterprises, some hypotheses are tested.

The results show: authoritarianism has a directly negative effect on exploitative innovation and positively moderates the effectiveness of exploitative innovation; benevolence has a directly positive effect both on exploratory innovation and exploitative innovation; benevolence negatively moderates the effectiveness of exploratory innovation and positively moderates the effectiveness of exploitative innovation.

This paper adopts the cross‐sectional study design, while innovation and formation of the implementation are relatively long‐term, dynamic processes. Thus, longitudinal design is a direction worth trying in follow‐up studies. Besides, using random samples affects to some extent the conclusion's generalizability.

Proper patriarchal leadership behavior (authoritarianism/benevolence) should be employed in the face of different types of innovation activities (exploratory innovation/exploitative innovation) and at the different stages of innovative activities (innovation ideas emerging stage/innovation behavior implementation stage). If properly used, patriarchal leadership with both authoritarianism and benevolence will effectively enhance innovation performance. Conversely, it may produce negative effects.

This paper has studied the influence of paternalistic leadership on exploratory and exploitative innovation. Different from the existing literature, this paper based on Daft's dual‐core model and Duncan's ambidextrous model and builds an integrated model.

The paper takes the air-ground integrated wireless ad hoc network-integrated system as the research object, this paper aims to propose a distributed robust H_∞ adaptive fault-tolerant control algorithm suitable for the system to distribute to solve the problem of control and communication failure at the same time.

In the paper, the authors propose a distributed robust H_∞ adaptive fault-tolerant control algorithm suitable for the air-ground integrated wireless ad hoc network-integrated system.

The results show that the integrated system has good robustness and fault tolerance performance indicators for flight control and wireless signal transmission when confronted with external disturbances, internal actuator failures and wireless network associated failures and the flight control curve of the quadrotor unmanned aerial vehicle (UAV) is generally smooth and stable, even if it encounters external disturbances and actuator failures, its fault tolerance performance is very good. Then in the range of 400–800 m wireless communication distance, the success rate of wireless signal loop transmission is stable at 80%–100% and the performance is at least relatively improved by 158.823%.

This paper takes the air-ground integrated wireless ad hoc network-integrated system as the research object, based on the robust fault-tolerant control algorithm, the authors propose a distributed robust H_∞ adaptive fault-tolerant control algorithm suitable for the system and through the Riccati equation and linear matrix inequation method, the designed distributed robust H_∞ adaptive fault-tolerant controller further optimizes the fault suppression factor γ, so as to break through the limitation of only one Lyapunov matrix for different fault modes to distribute to solve the problem of control and communication failure at the same time.

The six-axis force/torque sensor based on a Y-type structure has the advantages of simple structure, small space volume, low cost and wide application prospects. To meet the overall structural stiffness requirements and sensor performance requirements in robot engineering applications, this paper aims to propose a Y-type six-axis force/torque sensor.

The performance indicators such as each component sensitivities and stiffnesses of the sensor were selected as optimization objectives. The multiobjective optimization equations were established. A multiple quadratic response surface in ANSYS Workbench was modeled by using the central composite design experimental method. The optimal manufacturing structural parameters were obtained by using multiobjective genetic algorithm.

The sensor was optimized and the simulation results show that the overload resistance of the sensor is 200%F.S., and the axial stiffness, radial stiffness, bending stiffness and torsional stiffness are 14.981 kN/mm, 16.855 kN/mm, 2.0939 kN m/rad and 6.4432 kN m/rad, respectively, which meet the design requirements, and the sensitivities of each component of the optimized sensor have been well increased to be 2.969, 2.762, 4.010, 2.762, 2.653 and 2.760 times as those of the sensor with initial structural parameters. The sensor prototype with optimized parameters was produced. According to the calibration experiment of the sensor, the maximum Class I and II errors and measurement uncertainty of each force/torque component of the sensor are 1.835%F.S., 1.018%F.S. and 1.606%F.S., respectively. All of them are below the required 2%F.S.

Hence, the conclusion can be drawn that the sensor has excellent comprehensive performance and meets the expected practical engineering requirements.

With the rapid development of railway-intelligent video technology, scene understanding is becoming more and more important. Semantic segmentation is a major part of scene understanding. There is an urgent need for an algorithm with high accuracy and real-time to meet the current railway requirements for railway identification. In response to this demand, this paper aims to explore a variety of models, accurately locate and segment important railway signs based on the improved SegNeXt algorithm, supplement the railway safety protection system and improve the intelligent level of railway safety protection.

This paper studies the performance of existing models on RailSem19 and explores the defects of each model through performance so as to further explore an algorithm model dedicated to railway semantic segmentation. In this paper, the authors explore the optimal solution of SegNeXt model for railway scenes and achieve the purpose of this paper by improving the encoder and decoder structure.

This paper proposes an improved SegNeXt algorithm: first, it explores the performance of various models on railways, studies the problems of semantic segmentation on railways and then analyzes the specific problems. On the basis of retaining the original excellent MSCAN encoder of SegNeXt, multiscale information fusion is used to further extract detailed features such as multihead attention and mask, solving the problem of inaccurate segmentation of current objects by the original SegNeXt algorithm. The improved algorithm is of great significance for the segmentation and recognition of railway signs.

The model constructed in this paper has advantages in the feature segmentation of distant small objects, but it still has the problem of segmentation fracture for the railway, which is not completely segmented. In addition, in the throat area, due to the complexity of the railway, the segmentation results are not accurate.

The identification and segmentation of railway signs based on the improved SegNeXt algorithm in this paper is of great significance for the understanding of existing railway scenes, which can greatly improve the classification and recognition ability of railway small object features and can greatly improve the degree of railway security.

This article introduces an enhanced version of the SegNeXt algorithm, which aims to improve the accuracy of semantic segmentation on railways. The study begins by investigating the performance of different models in railway scenarios and identifying the challenges associated with semantic segmentation on this particular domain. To address these challenges, the proposed approach builds upon the strong foundation of the original SegNeXt algorithm, leveraging techniques such as multi-scale information fusion, multi-head attention, and masking to extract finer details and enhance feature representation. By doing so, the improved algorithm effectively resolves the issue of inaccurate object segmentation encountered in the original SegNeXt algorithm. This advancement holds significant importance for the accurate recognition and segmentation of railway signage.

This study aims to optimise the effect of pre-oxidation on hot corrosion behaviour of Tribaloy T-900 at 900 °C in mixed Na₂SO₄ and K₂SO₄.

Prior to hot corrosion experiment, pre-oxidation treatments were carried in ambient air at 900 °C for 1, 5 and 10 h, respectively. The hot corrosion experiments were performed in a box type furnace at 900 °C. Both surfaces of specimens were brushed with saturated salt solution of 75 wt.% Na₂SO₄ + 25 wt.% K₂SO₄. After brushing, the salt-coated specimens were placed in electric stove to ensure drying of salt. After drying, presence of 3 mg/cm² salt on specimen’s surface was ensured through weighting.

The 1-h pre-oxidation treatment prior to hot corrosion showed superior hot corrosion resistance against molten salt attack. An optimum pre-oxidation time of 1 h helped timely formation of protective Cr₂O₃ layer and inhibited the formation of less stable and porous surface oxides of Ni and Mo during hot corrosion.

Pre-oxidation effect on hot corrosion behaviour of refractory metal (such as Mo in investigated alloy) containing alloy has never been reported previously. Refractory metals oxide (e.g. MoO3) could transform the corrosion phenomena to catastrophic failure through acidic fluxing.

This paper aims to investigate how to improve new product performance in turbulent circumstances of emerging economies.

This paper used regression analysis to examine the performance impact of customer relationship management (CRM) and product development management (PDM) concentration strategy in new product development (NPD). A detailed contingent analysis of the market and institutional environments in emerging economies is also conducted based on a survey of 114 Chinese high-tech manufacturers.

The research findings show that PDM has a stronger positive effect on new product performance than CRM in emerging economies and that the contingent effects of the market and institutional environment vary. More specifically, technological turbulence and enforcement inefficiency can positively moderate the relationship between CRM and new product performance, whereas the moderating effect of market turbulence on CRM is negative. Meanwhile, enforcement inefficiency negatively moderates the effect of PDM on new product performance, while the moderating effect of market turbulence on PDM is positive.

This paper is limited to a survey of high-tech manufacturing enterprises in China. Further research should continues to explore and document the strategic issue about NPD in emerging economies by longitudinal study.

This paper contributed to theoretical and practical initiatives on the strategic issue of NPD and provided firms a further understanding of how to select the right NPD strategy in emerging economies to improve new product performance.

For any 3D model with chambers to be fabricated in powder-bed additive manufacturing processes such as SLM and SLS, powders are trapped in the chambers of the finished model. This paper aims to design a shortest network with the least number of outlets for efficiently leaking the trapped powders.

This paper proposes a nonlinear objective with linear constraints for solving the channel design problem and a particle swarm optimization algorithm to solve the nonlinear system.

Structural optimization for the channel network leads to fairly short channels in the interior of the 3D models and very few outlets on the model surface, which achieves the cleaning of the powders while causing almost the least changes to the model.

This paper reveals the NP-harness of computing the shortest channel network with the least number of outlets. The proposed approach helps the design of lightweight models using the powder-bed additive manufacturing techniques.

Currently, China is the largest coal producer and consumer in the world. Underground mining is the main practice. In the process of deep mining, large amounts of low-temperature waste heat are available such as in the mine return air (MRA), mine water (MW), bathing waste water (BWW), etc. Without recycling, the low-temperature waste heat is discharged directly into the atmosphere or into the drainage system. The temperature range of the MRA is about 15-25°C, the relative humidity (RH) of the MRA is above 90 per cent, the temperature range of MW is about 18-20°C and the temperature of the BWW is about 30°C. All of the above parameters are relatively stable throughout the year, and thus MRA, MW and BWW are proper low-temperature heat sources for water source heat pump (WSHP) systems. The study aims to introduce the schemes for recycling the different waste heat sources and the relevant key equipment and technology of each waste heat recycle system; analyze the heat recovery performances of the MRA heat recovery technology; and compare the economies between the MRA heat recovery system and the traditional system.

Based on the WSHP system, heat and mass transfer efficiencies were calculated and analyzed, the outlet air velocity diffusion of the heat and mass transfer units and the parameters including air flow rate, the MRA’s dry bulb temperatures and wet bulb temperatures at inlet and outlet of MRA heat exchanger were tested. Then, it was assessed whether this system can be applied to an actual construction. An actual reconstructive project of MRA heat recovery system is taken as an example, where the cost-saving effects of heat recovery of mine waste heat sources system are analyzed.

Analysis of field test reveals that when heat transfer is stable, heat transfer capacity can be achieved: 957.6 kW in summer, 681 kW in winter and a large amount of heat was recycled. In an economic analysis, by comparing initial investment and 10 years’ operation cost with the traditional boiler and central air conditioning system, the results show that although the MRA system’s initial investment is high, this system can save CNY 6.26m in 10 years.

MRA has a large amount of air volume and temperature that is constant throughout the year, and hence is a good low-temperature heat source for the WSHP system. It can replace boiler heating in winter and central air conditioning refrigeration in summer. The study reveals that this technology is feasible, and has good prospects for development.

Transport is an integral part of the nuclear fuel cycle. The procedures employed are designed and conducted to ensure the public and environment protection both routinely and when transport accidents occur. According to this, the purpose of this paper is to focus on a coupled thermal-drop impact analysis-based safety assessment of a nuclear fuel cask.

For the cask, high altitude falling and fire accidents are the two most serious accidents during its transportation. In this paper, a sequentially coupled thermal-drop impact analysis is performed by using a nuclear fuel cask model for safety assessment. High altitude falling and fire accidents of the nuclear fuel cask were conducted by using finite element simulations for coupled thermal-drop impact analysis.

Results showed that the cask can withstand a drop test and survive a fire of 800°C for 30 minutes. In addition, an improved design is explored and evaluated, which provides a reference for structural design and safety assessment of nuclear fuel casks.

A coupled thermal-drop impact analysis-based safety assessment procedure is developed for the nuclear fuel cask.