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The purpose of this paper is to analyze the market share of two competing enterprises from the perspective of consumer preferences on both of their products. For different industrial types, this paper discusses how domestic firms make decisions to compete with the multinational company based on consumer’s preferences on different types of products from different companies.

Considering the different types of equipment manufacturing industries, consumers’ differentiated preferences for Chinese domestic equipment manufacturers and multinational equipment manufacturers, as well as the uncertainty of technological level and dependence on production factor in reality, this paper introduces the interval grey number into the Stackelberg game model and analyzes the market share of two competing enterprises and the consumer preferences for both of their products based on different industrial types.

The results show that when both of the two competing firms are engaged in R&D activities, consumers prefer domestic products, and with the improvement of technological level, this preference grows stronger, but the market share of the multinational enterprise is higher than that of the local enterprises. When the two competing enterprises are engaged in manufacturing activities, consumers are more inclined to choose products of the multinational company, and with the increasing dependence on production factors, the preference becomes stronger. Meanwhile, the market share of the multinational company is higher than the local enterprise. Therefore, from the perspective of consumer preference, China’s domestic equipment manufacturing enterprises should choose technology-intensive or technology and labor-intensive industries (or dual-intensive industries).

In the context of international competition, from the perspective of consumer preference, the research on industrial selection is relatively rare, and does not take into account the influence of the uncertain influence brought by technological-level and production factor dependency. Therefore, this paper analyzes the influence of technological-level and production factor dependency on consumer preference among various types of industries. Based on the concept of consumer preference, and combining with the interval grey number, the improved grey game model is constructed to analyze the influence of the uncertainty of enterprise’s technological-level and production factor dependency on the market share of two competing companies, finally coming up with the direction into which the Chinese equipment manufacturing industries should develop.

To develop an image processing approach for jigsaw puzzle assembly.

First, pixels are extracted from the jigsaw puzzle blocks to calculate their rotation angles and centre coordinates. Second, a template matching method is employed to recognise each block and its orientation.

A robot‐based jigsaw puzzle system is established; and an effective image processing approach for assembly is developed.

Automatic assembly lines that assemble parts with the same shape, but random position and angle, can employ the jigsaw puzzle assembly method.

An effective image processing method for jigsaw puzzle assembly is presented in this paper. The validity of the method is proved by analysis and experiment.

Mega construction projects (megaprojects) require technological innovation cooperation (TIC) to address complex construction demands and the interests of multiple stakeholders. Although TIC has been extensively discussed at the firm level, a significant gap remains in understanding megaprojects at the project level. This paper aims to identify TIC’s influencing factors and transmission paths and discuss stakeholders’ TIC mechanisms at the project level.

Based on case analysis, expert interviews, literature analysis and the Delphi method, this paper identifies the influencing factors of TIC in megaprojects at the project level. A structural system of these influencing factors is constructed by interpretive structural modeling (ISM), developing various mechanisms for TIC from bottom to top. The Matriced’ Impacts Croisés Multiplication Appliquée à un Classement (MICMAC) method validates the driving forces and dependencies of the influencing factors, clarifying their roles and positions within the system. Additionally, the TIC mechanism is constructed.

The research findings identify 26 influencing factors categorized into four hierarchical levels: cooperative relationships, cooperative behavior, cooperative performance and technological innovation risks. Regarding direct factors, resource sharing affects goal congruence and communication effectiveness in megaprojects, affecting TIC’s satisfaction and trust. Most factors exist in the middle layer, and bridging the upper and lower levels depends on stakeholder collaboration. The root factors in the independent group significantly impact TIC, including policy circumstances, high technical requirements and limited site conditions. Addressing these issues influences improvements in other factors. The development of a digital resource-sharing platform, the enhancement of innovation incentives, the optimization of benefit distribution mechanisms and the improvement of risk-sharing mechanisms are essential for the effective operation of the TIC mechanism.

This study contributes to identifying and classifying challenges and opportunities in TIC. It explores transmission paths for enhancing TIC and presents strategies for successfully implementing and delivering megaprojects.

This paper aims to mainly discuss how to suppress the disturbances accurately and effectively in the wind energy conversion system (WECS) of the direct drive surface mount permanent magnet synchronous generator (SPMSG).

The disturbances in wind energy conversion system have seriously negative influence on the maximum power tracking performance. Therefore, a model predictive control (MPC) method of model compensation active disturbance rejection control (ADRC) strategy in parallel connection is designed, which optimizes the speed tracking performance compared with the existing control strategy of MPC and ADRC in series connection. Based on the traditional ADRC, a multi parameter model compensation ADRC strategy is added to better estimate the disturbances. At the same time, a torque feedback strategy is added to compensate the disturbances caused by load torque and further optimize the speed loop tracking performance.

The simulation results show that the designed control method has advantages than the traditional control method in compensating the disturbances and tracking the maximum power more effectively.

The simulation results show that the designed control method is superior to the traditional proportional control method, which can better compensate the internal and external disturbances and track the maximum power more effectively.

In order to determine the range of medium temperature zone of road asphalt, it is hoped that the evolution of viscoelastic characteristics of road asphalt under medium temperature state can be deeply explored.

In this paper, the needle penetration test and temperature scanning test were designed for 90# and 70# bitumen as test materials, and the boundary of medium temperature zone of 90# and 70# bitumen was accurately determined by data analysis method. A mathematical model was established based on principal component analysis, and a comprehensive evaluation index was proposed to evaluate the evolution of temperature viscoelastic characteristics of road asphalt by means of standardization and rotational dimensionality reduction.

The test results show that the medium temperature zone of 90# asphalt is [−5 ± 1°C, 38 ± 1°C], and the medium temperature zone of 70# asphalt is [0 ± 1°C, 51 ± 1°C]. According to the viscoelastic response of road asphalt in the medium temperature zone, the medium temperature zone can be divided into three evolution stages: weak viscoelastic stage, viscoelastic equilibrium stage, strong viscoelastic weak stage. Analysis based on the intrinsic viscosity fillip target describing the various intrinsic viscoelastic index represents the viscoelastic properties of bitumen from different angles, and limitations inherent stick fillip for target put forward the integrated the inherent stick fillip mark information, as well as targeted and accurate evaluation of road asphalt temperature comprehensive evaluation indexes in the evolution of the viscoelastic properties of I_M-T. Finally, the temperature data of asphalt pavement in several representative regions of China are compared with the determined medium temperature region, and it is proved that the research on the evolution of viscoelastic characteristics of asphalt pavement under the medium temperature condition has important practical significance.

The boundary of medium temperature zone of 90# and 70# base asphalt was determined, and the viscoelastic characteristic evolution of road asphalt under medium temperature state was studied deeply. Aiming at the limitation of intrinsic viscoelastic index, a comprehensive evaluation index IM-T which not only integrates the information of intrinsic viscoelastic index but also can accurately evaluate the evolution of temperature viscoelastic characteristics in road asphalt is proposed.

This study aims to construct a novel maximum power tracking control system for the direct drive permanent magnet synchronous generator (PMSG) of the wind energy conversion system (WECS) to solve the following problems: how to effectively eliminate the system’s model parameter disturbances and speed up the dynamic performance of the system; and how to eliminate harmonics in WECS under different wind speeds.

To obtain the maximum output power of PMSG at WECS under different wind speeds, the following issues should be considered: (1) how to effectively eliminate the system’s model parameter disturbances and speed up the dynamic performance of the system; and (2) how to suppress system harmonics. For Problem 1, adding d–q compensation factors to active disturbance rejection control (ADRC) for the current loop realizes the d–q axis decoupling control, which speeds up the dynamic performance of the system. For Problem 2, the resonant controller is introduced into the ADRC for the current loop to suppress harmonic current in WECS under different wind speeds.

The simulation results demonstrate that the proposed control method is simpler and more reliable than conventional controllers for maximum power tracking.

Compared with traditional controllers, the proposed controller can speed up the dynamic performance of the system and suppress the current harmonic effectively, thus better achieving maximum power tracking.

This study aims to improve the control accuracy and antidisturbance performance of the manipulator with the flexible link, a combined controller, which combines the novel backstepping sliding mode controller based on the extended state observer (ESO) and super-twisting sliding mode controller.

First, the dynamic of the system is constructed by Lagrange method and assumed mode method, and then the dynamic is decoupled by the singular perturbation theory to obtain the slow-varying subsystem and fast-varying subsystem. For the slow-varying subsystem, the novel backstepping sliding mode controller based on ESO is used to achieve joint tracking. For the fast-varying subsystem, the super-twisting sliding mode controller is used for vibration suppression. At the same time, to suppress chattering, the tanh function is used to replace the sign function in the reaching law.

The simulation results show that the combined control has better trajectory tracking performance, antiinterference performance and vibration suppression performance than traditional sliding mode control (SMC).

A novel backstepping sliding mode controller based on ESO is designed to guarantee the performance of the tracking trajectory. The new controller improves the converge rate. A super-twisting sliding mode controller, which can stabilize the fast-varying subsystem, is used to suppress the vibration of flexible link.

This paper aims to propose a new solution for real-time 3D perception with monocular camera. Most of the industrial robots’ solutions use active sensors to acquire 3D structure information, which limit their applications to indoor scenarios. By only using monocular camera, some state of art method provides up-to-scale 3D structure information, but scale information of corresponding objects is uncertain.

First, high-accuracy and scale-informed camera pose and sparse 3D map are provided by leveraging ORB-SLAM and marker. Second, for each frame captured by a camera, a specially designed depth estimation pipeline is used to compute corresponding 3D structure called depth map in real-time. Finally, depth map is integrated into volumetric scene model. A feedback module has been designed for users to visualize intermediate scene surface in real-time.

The system provides more robust tracking performance and compelling results. The implementation runs near 25 Hz on mainstream laptop based on parallel computation technique.

A new solution for 3D perception is using monocular camera by leveraging ORB-SLAM systems. Results in our system are visually comparable to active sensor systems such as elastic fusion in small scenes. The system is also both efficient and easy to implement, and algorithms and specific configurations involved are introduced in detail.

This study aims to explore the impact of printing parameters, specifically raster angle and layer thickness, on the microstructure and mechanical properties of green and sintered parts produced through filament-based fused filament fabrication (FFF) using a self-developed filament. The goal is to improve the quality and performance of the final sintered components.

A filament containing 92 Wt.% 316L stainless steel with polyoxymethylene (POM)-based binder was formulated and evaluated for flexibility through a buckling resistance test. Green parts were printed with varying raster angles (+45°/−45°, 0°/90°) and layer thicknesses (0.2 mm, 0.3 mm), followed by catalytic debinding and high-temperature sintering. Microstructure, dimensional accuracy and mechanical properties, including microhardness, tensile strength and elongation at break, were analyzed to identify optimal parameters.

A raster angle of (+45°/−45°) produced denser interlayer bonding and a more compact green part structure, whereas a thicker layer (0.3 mm) resulted in a looser structure with larger pores. The optimal combination of +45°/−45° raster angle and 0.2 mm layer thickness achieved the highest relative density (99.37%) and superior mechanical properties: microhardness (216.83 HV), tensile strength (467.59 MPa) and elongation at break (16.81%).

A 92 Wt.% 316L stainless-steel filament for FFF was independently developed and near dense steel components were successfully fabricated. This study provides new insight into developing a novel formula of filament and optimizing printing parameters for FFF technology.

In this paper, an optical inspection method of the ball grid array package(BGA) is proposed using a binocular machine vision system.

The height of each solder ball is calculated based on spatial geometrical size and location obtained from the two CCD cameras capturing range images of a LED illuminated BGA chip at certain orientation.

The structure of this system is simple and the accuracy is 0.02 mm, The experimental results have proved the validity of this system for BGA failure detection.

The developed machine vision system can provide some of the critical factors for BGA quality evaluation, such as the height of solder ball, diameter, pitch and coplanarity.

Compared with other systems, the structure of this system is simple and accurate, which meets the demand of off‐line and on‐line inspection. The limitation of this system is that the margin of field of view (FOV) is fuzzy. Further study could be focused on this problem.