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The application of thermal barrier coatings (TBCs) allows aero-engine blades to operate at higher temperatures with higher efficiency. The preparation of the TBCs increases the surface roughness of the blade, which impacts the thermal cycle life and thermal insulation performance of the coating. To reduce the surface roughness of blades, particularly the blades with small size and complex curvature, this paper aims to propose a method for industrial robot polishing trajectory planning based on on-site measuring point cloud.

The authors propose an integrated robotic polishing trajectory planning method using point cloud processing technical. At first, the acquired point cloud is preprocessed, which includes filtering and plane segmentation algorithm, to extract the blade body point cloud. Then, the point cloud slicing algorithm and the intersection method are used to create a preliminary contact point set. Finally, the Douglas–Peucker algorithm and pose frame estimation are applied to extract the tool-tip positions and optimize the tool contact posture, respectively. The resultant trajectory is evaluated by simulation and experiment implementation.

The target points of trajectory are not evenly distributed on the blade surface but rather fluctuate with surface curvature. The simulated linear and orientation speeds of the robot end could be relatively steady over 98% of the total time within 20% reduction of the rest time. After polishing experiments, the coating roughness on the blade surface is reduced dramatically from Ra 7–8 µm to below Ra 1.0 µm. The removal of the TBCs is less than 100 mg, which is significantly less than the weight of the prepared coatings. The blade surface becomes smoothed to a mirror-like state.

The research on robotic polishing of aero-engine turbine blade TBCs is worthwhile. The real-time trajectory planning based on measuring point cloud can address the problem that there is no standard computer-aided drawing model and the geometry and size of the workpiece to be processed differ. The extraction and optimization of tool contact points based on point cloud features can enhance the smoothness of the robot movement, stability of the polishing speed and performance of the blade surface after polishing.

The purpose of this paper is to develop a modelling approach that enables the analysis of long-term food security policies. Specifically, the authors explore the effect of China’s agricultural domestic support on its agricultural and food market by also considering the impact of incomplete price transmission.

The authors extend the standard Global Trade Analysis Project (GTAP) modelling framework. First, the authors incorporate incomplete price transmission into the GTAP model by generating tariff-equivalent price transmission elasticities. Second, the authors improve the current representation of China’s agricultural domestic support in the GTAP model and the underlying database by considering the production requirements and the trade-distorting effect of different policy instruments. Running a set of simulations, the authors examine first how the incorporation of incomplete price transmission affects the model’s results and second how increased agricultural domestic support affects China’s agricultural and food market accounting for incomplete price transmission.

Considering incomplete price transmission mitigates the domestic price increases as responses to high international agricultural prices, which also lead to an increase in China’s trade deficit and prohibits net food sellers from receiving high prices. In the long term, an increase in China’s agricultural domestic support to its World Trade Organisation de minimis commitment level would increase domestic agricultural production and reduce its demand pressure on the international market.

This paper contributes to the literature by examining the impact of increased agricultural domestic support on the domestic market while innovatively accounting for incomplete food price transmission. The authors combine econometric estimated price transmission elasticities and an extended GTAP framework to underscore the importance of enhancing the model’s ability in accounting for incomplete price transmission when analysing the impact of agricultural policies.

This paper aims to investigate Cu/SnAgCu/Cu transient liquid phase (TLP) bonding with different thicknesses for three-dimensional (3D) integrated circuit (IC).

This paper includes experiments and finite element simulation.

The growth rate of the intermetallic compound layer during TLP soldering was calculated to be 0.6 μm/s, and the small scallop-type morphology Cu₆Sn₅ grains can be observed. With the decrease in thickness in solder joint, the thickness of intermetallic compounds represents the same size and morphology, but the size of eutectic particles (Ag₃Sn, Cu₆Sn₅) in the matrix microstructure decrease obviously. It is found that with the increase in thickness, the tensile strength drops obviously. Based on finite element simulation, the smaller value of von Mises demonstrated that the more reliability of lead-free solder joints in 3D IC.

The Cu/SnAgCu/CuTLPbondingwithdifferentthicknessesfor3D IC was investigated.

In order to find an appropriate method to synthesize a new high-efficiency flame retardant for epoxy resin.

In this work, a flame retardant with heterocyclic groups, HOMP, was acquired after removing the obstacle from triazines which was not readily soluble. The molecular structure, thermal and flame retardant properties were fully characterized and analyzed. Also, the mechanism was researched through multi-methodologies. As well, the authors evaluated the effects of HOMP on mechanical properties.

The results suggested that HOMP helped extinguish the combustion of specimens and could reach an LOI value of 29.2% and the V0 level in the UL-94 test with a phosphorus content of only 0.6wt%. With respect to the mechanism, HOMP was a gas-phase flame retardant and helped generate a thicker carbon protective coating. However, for the mechanical properties, the addition of HOMP enhanced the compressibility, while the tensile strength decreased significantly.

The approach not only simplified the operations but also obtained HOMP with excellent flame retardant properties.

This paper aims at building a discharge model for the power cable bellows based on plasma energy deposition and analyzing the discharge ablation problem.

Aiming at the multiphysical mechanism of the discharge ablation process, a multiphysical field model based on plasma energy deposition is established to analyze the discharge characteristics of the power cable bellows. The electrostatic field, plasma characteristics, energy deposition and temperature field are analyzed. The discharge experiment is also carried out for result validation.

The physical mechanism of the bellows ablative effect caused by partial discharge is studied. The results show that the electric field intensity between the aluminum sheath and the buffer layer easily exceeds the pressure resistance value of air breakdown. On the plasma surface of the buffer layer, the electron density is about 4 × 1,019/m³, and the average temperature of electrons is about 3.5 eV. The energy deposition analysis using the Monte Carlo method shows that the electron range in the plasma is very short. The release will complete within 10 nm, and it only takes 0.1 s to increase the maximum temperature of the buffer layer to more than 1,000 K, thus causing various thermal effects.

Its physical process involves the distortion of electric field, formation of plasma, energy deposition of electrons, and abrupt change of temperature field.

To cope with the severe situation of the global climate, China proposed the “30 60” dual-carbon strategic goal. Based on this background, the purpose of this paper is to investigate scientifically and reasonably the interprovincial pattern of China’s power carbon emission intensity and further explore the causes of differences on this basis.

Considering the principle of “shared but differentiated responsibilities,” this study measures the carbon emissions within the power industry from 1997 to 2019 scientifically, via the panel data of 30 provinces in China. The power carbon emission intensity is chosen as the indicator. Using the Dagum Gini coefficient to explore regional differences and their causes.

The results of this paper show that, first, China’s carbon emission intensity from the power industry overall is significantly different. From the perspective of geospatial distribution, the three regions have unbalanced characteristics. Second, according to the decomposition results of the Gini coefficient, the overall difference in power carbon emission intensity is generally expanding. The geospatial and economic development levels are examined separately. The gaps between the eastern and economically developed regions are the smallest, and the regional differences are the source of the overall disparity.

Further exploring the causes of differences on this basis is crucial for relevant departments to formulate differentiated energy conservation and emission reduction policies. This study provides direction for analyzing the green and low carbon development of China’s power industry.

As an economic indicator of green and low-carbon development, CO₂ intensity of power industry can directly reflect the dependence of economic growth on the high emission of electricity and energy. and further exploring the causes of differences on this basis is crucial for relevant departments to formulate differentiated energy conservation and emission reduction policies.

For a long time, with the rapid economic development, resulting in the unresolved contradiction between low energy efficiency and high carbon emissions. To this end, scientifically and reasonably investigating the interprovincial pattern of China’s power carbon emission intensity, and further exploring the causes of differences on this basis, is crucial for relevant departments to formulate differentiated energy conservation and emission reduction policies.

Third, considering the influence of spatial factors on the convergence of power carbon emission intensity, a variety of different spatial weight matrices are selected. Based on the β-convergence theory from both absolute and conditional perspectives, we dig deeper into the spatial convergence of electricity carbon emission intensity across the country and the three regions.

During the process of the robotic grinding and polishing operations on aero-engine blades, the key problem of calibration error lies in fixture error and uneven margin. To solve this problem, this paper aims to propose a novel method to achieve rapid online calibration of the workpiece coordinate system through laser-based measurement techniques.

The authors propose a calibration strategy based on point cloud registration algorithm. The main principle is presented as follows: aero blade mounted on clamping end-effector is hold by industry robot, the whole device is then scanned by a 3D laser scanner to obtain its surface point cloud, and a fast segmentation method is used to acquire the point cloud of the workpiece. Combining Super4PCS algorithm with trimmed iterative closest point, we can align the key points of the scanned point cloud and the sampled points of the blade model, thus obtaining the translation and rotation matrix for calculating the workpiece coordinate and machining allowance. The proposed calibration strategy is experimentally validated, and the positioning error, as well as the margin distribution, is finally analyzed.

The experimental results show that the algorithm can well accomplish the task of cross-source, partial data and similar local features of blade point cloud registration with high precision. The total time spent on point cloud alignment of 100,000 order of magnitude blade is about 4.2 s, and meanwhile, the average point cloud alignment error is reduced to below 0.05 mm.

An improved point cloud registration method is proposed and introduced into the calibration process of a robotic system. The online calibration technique improves the accuracy and efficiency of the calibration process and enhances the automation of the robotic grinding and polishing system.

This paper aims to identify the most influential barriers for environmental management system (EMS) adoption and determine the interactions of these factors in the context of Chinese textile and apparel industries.

The study has conducted two different research phases, namely, the identification of 13 barriers from the extensive literature available and expert panel discussion and using interpretive structural modeling (ISM) to investigate the complex relationships among these barriers and partition the barriers into a hierarchical structure to facilitate strategic analysis.

The obtained result demonstrates that insufficient information about customer’s demand is the most influential barrier. Furthermore, by analyzing the interrelationships among the barriers, management will become more aware of the barriers’ relative importance and focus on the barriers with stronger influence.

This work may help practitioners, academicians and regulators to focus their efforts toward implementation of EMS on various levels in business, especially for these textile and apparel companies operating in China.

The purpose of this paper is to empirically examine the underlying impacts of customer orientation on new product development (NPD) performance. Further, this study investigates the moderating effect of top management support (TMS) on the customer orientation-performance relationship.

This study as a unique approach has classified customer orientation into three sub-dimensions: customer focus, customer involvement and communication with customers. And the NPD performance is explored both from financial and nonfinancial aspects.

Based on a sample of 366 high performance manufacturing firms across ten countries, the obtained results of hierarchical moderated regression analyses reveal that customer focus, customer involvement and communication with customers have significantly positive effects on both financial and nonfinancial performance of NPD; TMS positively moderates the relationship between multiple dimensions of customer orientation and NPD performance.

The research extends the customer orientation literature by describing three dimensions of customer orientation and empirically testing their effects on NPD performance. This study also contributes to a deep understanding of the influence factors of NPD performance, both from the financial and nonfinancial aspects. The proposed framework provides a fine-grained analysis to help us understand in what way the customer orientation is linked to performance outcomes.

This study is innovative because it seeks to make a contribution to existing literature from a theoretical perspective by investigating the sub-dimensions of customer orientation and moderating role of TMS.

The purpose of this paper is to bridge the gap in understanding the effects of external involvement on new product market performance. Particularly, the authors investigate the mediating effects of speed-to-market of new products and moderating effects of information technology (IT) implementation.

This study is based on the high-performance manufacturing (HPM) project database collected from 366 manufacturing plants in ten countries and three representative industries. The hierarchical regression analysis is employed to explore the relationships in the model.

The empirical findings indicate that speed-to-market of new products positively and significantly mediates the relationship between customer involvement and new product market performance. The results also demonstrate that IT implementation moderates the relationship between external involvement and speed-to-market of new products. More importantly, the findings reveal that supplier involvement is less likely to lead to the enhancement of speed-to-market if the firm is not able to establish a higher level of IT implementation.

This analysis uncovers the way of how customer and supplier involvement are related to new product market performance, and highlights the importance of IT implementation in absorbing and exploiting external resources.

This paper moves us from a simplistic understanding of external involvement to a more nuanced and complex model which is closer to reality. The obtained findings highlight the importance for manufacturers to establish speed advantage of new products and implement IT as an enabler.