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The purpose of this paper is to solve the diverse and complex problems of flat-knitting sports upper process design, improve the design ability of upper organization, and realize three-dimensional simulation function.

Firstly, the matrix is used to establish the corresponding pattern diagram and organizational diagram model, and the relationship between the two is established by color coding as a bridge to completed the transformation of the flat-knitted sports upper process design model. Secondly, the spatial coordinates of the loop type value points are obtained through the establishment of loop mesh model, the index of two-dimensional and three-dimensional models of uppers and the establishment of spatial transformation relationship. Finally, using Visual Studio as a development tool, use the C# language to implement this series of processes.

Digitizing the fabric into a matrix model, combined with matrix transformation, can quickly realize the design of the flat-knitting process. Taking the knitting diagram of the upper process as the starting point, the loop geometry model corresponding to the element information is established, and the three-dimensional simulation effect of the flat-knitted upper based on the loop structure is realized under the premise of ensuring that it can be knitted.

This paper proposes a design and modeling method for flat-knitted uppers. Taking the upper design process and 3D simulation effect as an example, the feasibility of the method is verified, which improves the efficiency of the development of the flat-knitted upper product and lays the foundation for the high-end customization of the flat-knitted upper.

Based on the background of enterprise digital transformation, this paper aims to examine the impact of digitization on the cooperative behavior and environmental performance of green technology innovation.

By constructing a model of quantity competition between the two enterprises, this paper examines the impact of digitization on the cooperative behavior and environmental performance of green technology innovation from the micro level. It uses Shanghai and Shenzhen A-share-listed companies as research samples. An unbalanced panel data set from 2011 to 2018 was constructed to empirically test the effect of digital transformation on the environmental performance of enterprises.

The findings reveal the following. First, digital transformation can significantly improve the environmental performance of enterprises. Second, green technological innovation sharing plays an intermediary role between digital transformation and enterprise environmental performance. Third, when the level of digitization is high, the sharing effect of green technology innovation brought about by digital technology is stronger and enterprises tend to carry out cooperative green technology innovation. Lastly, the level of development of regional science and technology finance plays a positive regulatory role in digital transformation and enterprise environmental performance.

This paper first proposes that green technology innovation-sharing is an important mechanism that can significantly improve enterprises' environmental performance. The authors empirically examine the mechanism and analyze the heterogeneity of the impact of digitalization level on enterprises' environmental performance. The authors also discuss the moderating effect of regional technology and finance development levels on the relationship between digitalization and enterprises' environmental performance.

The purpose of this paper is to conveniently and accurately design partial knitting knitted fabrics based on matrix transformation.

Using mathematical modeling, the pattern diagram block matrix and process design matrix of partial knitting knitted fabrics are established, and the process knitting diagram with parameter information is generated. Based on the establishment of the mathematical model of the process knitting diagram, a loop deformation method based on three-dimensional (3D) coordinate point matrix transformation is proposed.

The matrix transformation method can provide a suitable deformed loop mode for partial knitting knitted fabrics and helps to generate a 3D modeling diagram conveniently.

This paper proposed a method of design and modeling of partial knitting knitted fabric based on matrix transformation. Taking the 3D modeling effect of conventional partial knitting as an example to test the modeling method, the results show that after matrix transformation, the loop model can realize the rapid transformation and calculation of the coordinates of the control point and generate a 3D modeling diagram.

With the twin screw extruder being widely used, there are a lot of parameters considered in the method, and the extruder’s volume is an important parameter of twin screw extruders among them. In this paper, some of the extruder parameters such as the impacting extruder volume are introduced, and the mathematical relationship in these parameters is interpreted. The minimum power consumption is the goal of the authors’ structural design.

This paper further applies genetic algorithm, a kind of intelligent optimization methods, to obtain the most optimized design dimension, and power consumption function related to unit output of extruder is used as the optimizing target. Meanwhile, this paper takes channel depth of feeding section, channel depth of extrusion section affecting the energy consumption, the width of flight top and helix angle as design variables.

By using genetic algorithm, the optimal structure size is obtained, and the power consumption is minimum.

With the use of optimizing the structure, the power of consumption is reduced. This method has important economic significance and important social significance on energy saving.

The purpose of this paper is to investigate the effect of selective laser sintering (SLS) method on morphology and performance of polyamide 12.

Crystallization behavior is critical to the properties of semi-crystalline polymers. The crystallization condition of SLS process is much different from others. The morphology of polyamide 12 produced by SLS technology was investigated using scanning electron microscopy, polarized light microscopy, differential scanning calorimetry, X-ray diffraction and wide-angle X-ray diffraction.

Too low fill laser power brought about bad fusion of powders, while too high energy input resulted in bad performance due to chain scission of macromolecules. There were three types of crystal in the raw powder material, denoted as overgrowth crystal, ring-banded spherulite and normal spherulite.

In this work, SLS samples with different sintering parameters, as well as compression molding sample for the purpose of comparison, were made to study the morphology and crystal structure of sintered PA12 in detail.

This paper aims to investigate an efficient approach to model the electromagnetic behaviors and predict stray-field loss inside the magnetic steel plate under 3D harmonic magnetization conditions so as to effectively prevent the structural components from local overheating and insulation damage in electromagnetic devices.

An experimental setup is applied to measure all the magnetic properties of magnetic steel plate under harmonic excitations with different frequencies and phase angles. The measurement and numerical simulation are carried out based on the updated TEAM Problem 21 Model B+ (P210-B+), under the 3D harmonic magnetization conditions. An improved method to evaluate the stray-field loss is proposed, and harmonic flux distribution in the structural components is analyzed.

The influence of the harmonic order and phase angle on the stray-field loss in magnetic steel components are noteworthy. Based on the engineering-oriented benchmark models, the variations of stray-field losses and magnetic field distribution inside the magnetic components under harmonic magnetization conditions are presented and analyzed in detail.

The capacity of the multi-function harmonic source, used in this work, was not large enough, which limits the magnetization level. Up to now, further improvements to increase the harmonic source capacity and investigations of the electromagnetic behaviors of magnetic steel components under multi-harmonic and DC-AC hybrid excitations are in progress.

To accurately predict the stray-field loss in magnetic steel plate, the improved method based on the combination of magnetic measurement and numerical simulation is proposed. The effects of the frequency and phase angle on the stray-field loss are analyzed.

This paper aims to study the influence of microparticles on the surface cavitation behavior of 2Cr3WMoV steel; microparticle suspensions of different concentration, particle size, material and shape were prepared based on ultrasonic vibration cavitation experimental device.

2Cr3WMoV steel was taken as the research object for ultrasonic cavitation experiment. The morphology, quantity and distribution of cavitation pits were observed and analyzed by metallographic microscope and scanning electron microscope.

The study findings showed that the surface cavitation process produced pinhole cavitation pits on the surface of 2Cr3WMoV steel. High temperature in the process led to oxidation and carbon precipitation on the material surface, resulting in the “rainbow ring” cavitation morphology. Both the concentration and size of microparticles affected the number of pits on the material surface. When the concentration of microparticles was 1 g/L, the number of pits reached the maximum, and when the size of microparticles was 20 µm, the number of pits reached the minimum. The microparticles of Fe3O4, Al2O3, SiC and SiO2 all increased the number of pits on the surface of 2Cr3WMoV steel. In addition, the distribution of pits of spherical microparticles was more concentrated than that of irregularly shaped microparticles in turbidity.

Most of the current studies have not systematically focused on the effect of each factor of microparticles on the cavitation behavior when they act separately, and the results of the studies are more scattered and varied. At the same time, it has not been found to carry out the study of microparticle cavitation with 2Cr3WMoV steel as the research material, and there is a lack of relevant cavitation morphology and experimental data.

This paper aims to investigate the anti-icing performance of the nanosecond dielectric barrier discharge (NSDBD) plasma actuator.

With the Lagrangian approach and the Messinger model, two different ice shapes known as rime and glaze icing are predicted. The air heating in the boundary layer over a flat plate has been simulated using a phenomenological model of the NSDBD plasma. The NSDBD plasma actuators are planted in the leading edge anti-icing area of NACA0012 airfoil. Combining the unsteady Reynolds-averaged Navier–Stokes equations and the phenomenological model, the flow field around the airfoil is simulated and the effects of the peak voltage, the pulse repetition frequency and the direction arrangement of the NSDBD on anti-icing performance are numerically investigated, respectively.

The agreement between the numerical results and the experimental data indicates that the present method is accurate. The results show that there is hot air covering the anti-icing area. The increase of the peak voltage and pulse frequency improves the anti-icing performance, and the direction arrangement of NSDBD also influences the anti-icing performance.

A numerical strategy is developed combining the icing algorithm with the phenomenological model. The effects of three parameters of NSDBD on anti-icing performance are discussed. The predicted results show that the anti-icing method is effective and may be helpful for the design of the anti-icing system of the unmanned aerial vehicle.

This study aims to explore the innovative capabilities of building information modeling (BIM) in construction projects. The objectives are to construct an inclusive conceptual framework of BIM-enabled construction innovation, identify the status and trends of innovation-related research in BIM publications, synthesize research pertaining to BIM-enabled construction innovation and discover core research requirements in the related body of knowledge.

This study proposes a comprehensive theoretical framework, named innovation pyramid, comprising context, actor, artifact, process, structure and innovative task for exploring and analyzing the innovative capability of BIM in construction projects. Accordingly, mixed methods were used to perform a systematic review of research on the topic of BIM-enabled construction innovation.

The findings reveal that BIM innovation-related articles have predominantly considered BIM as an innovation from a technological standpoint, while the innovative capabilities of BIM have remained under-researched with a fragmented research focus. Fertile grounds for research have emerged and call for research pertaining to entities of “structure” and “innovative task” as well as interaction, interrelations and mutually adjusting effect among the entities.

The framework proposed may be useful for subsequent research design and for assisting project management practitioners in the use of BIM to achieve innovation more efficiently.

This research provides an insight into the innovative capabilities of BIM based on the BIM–collaboration–construction innovation logic chain. It contributes to the body of knowledge by devising an inclusive conceptual framework of BIM-enabled construction innovation, synthesizing the state of the art and exposing the research needs in this area.