In this paper, a 2R1T (two rotations and one translation) over-constrained parallel mechanism R(2RPR)R/SP with two ordered continuous rotational axes is proposed, which contains fewer joints, by concatenating a 2-degr...
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The simulation of drilling condition and swing condition is completed with *** cutting patterns of cutting process is drawn for cutting head of longitudinal axial *** variations of c
The simulation of drilling condition and swing condition is completed with *** cutting patterns of cutting process is drawn for cutting head of longitudinal axial *** variations of c
In order to implement the optimization design for a forging aluminum wheel, the wheel's structural optimization design software, i.e. DWheel, was developed in this paper. DWheel was programmed based on C# and ANSY...
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The macro-scale and meso-scale simulation models of stainless steel clad plate were established by DEFORM-3D. The multi-scale coupling simulations of clad plate with different rolling parameters were carried out. The ...
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The horizontal yaw cutting condition of the picks was analyzed to study the load characteristics of a roadheader’s cutting *** on theoretical calculation,the range of the cutting angle was cert
The horizontal yaw cutting condition of the picks was analyzed to study the load characteristics of a roadheader’s cutting *** on theoretical calculation,the range of the cutting angle was cert
The shortage of water resources is a major challenge of the world,seawater desalination is the best way to solve the crisis of water *** osmosis membrane desalination equipment needs to
The shortage of water resources is a major challenge of the world,seawater desalination is the best way to solve the crisis of water *** osmosis membrane desalination equipment needs to
Basal fracture due to dwell fatigue (DF) is primary cause of core material failure during aero-engine service, which highlights the importance of understanding the crack initiation mechanism. In this study, the relati...
Basal fracture due to dwell fatigue (DF) is primary cause of core material failure during aero-engine service, which highlights the importance of understanding the crack initiation mechanism. In this study, the relationship between activation of plastic slip within the [0001] basal plane orientation, local strain and crack initiation in near-α Ti60 alloys was investigated using coupled in situ and high-resolution digital image correlation (HR-DIC) methods. The results show that basal slip is preferentially activated resulting into a higher shear strain in DF compared to [10 1 ¯ 0] prismatic orientation grains. Two types of cracking induced by strong basal slip were identified in grains with medium to high basal Schmidt factor (SF): slip transgranular cracking and basal twist grain boundary (BTGB) cracking. The slip deformation and strain evolution of the two types of cracks before and after their initiation were observed for the first time on the sample surface by in-situ dwell, which provides experimental and theoretical support for their formation mechanism. In order to constitute potential locations for crack nucleation, these regions have high local and shear strains during the basal slip stage prior to crack initiation. The higher local strain in the former is attributed to the intrusion and extrusion mechanism of the slip bands, while the latter is attributed to the inconsistency of the slip deformation of the microscopic dislocations on both sides of the BTGB making the GB slip-shear. Additionally, the incoordination on both sides of the GB, coupled with the inherently low cleavage energy, makes the BTGB more susceptible to cracking compared to slip transgranular cracking. No elemental segregation or β-phase influence was observed at the grain boundary interface. This study provides new insights into the mechanisms involved basal slip-induced cracking in Ti alloys subjected to dwell loadings.
In the traditional quantum genetic algorithm, the rotation angle and direction of the quantum rotation gate should be looked up from the lookup table which has been designed according to the specific problem. However,...
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The axial piston pump usually works under variable speed *** is important to evaluate the health status of the axial piston pump under the variable speed *** at the characteristic signals obtained under different wear...
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The axial piston pump usually works under variable speed *** is important to evaluate the health status of the axial piston pump under the variable speed *** at the characteristic signals obtained under different wear levels of the port plate,a feature signal extraction method under variable speed conditions is ***,the combination of complete ensemble empirical mode decomposition with adaptive noise(CEEMDAN)energy spectrum and fast spectral kurtosis principle is used to accurately extract the intrinsic mode function(IMF)component containing the sensitive information of the degraded ***,the aspect ratio analysis method of the angle domain variational mode decomposition(VMD)is used to process the feature index containing the sensitive information of the degraded *** order to evaluate the health status of the axial piston pump under variable speed,the vibration reliability analysis method for axial piston pump based on Weibull proportional failure rate model is *** experimental results show that the proposed method can accurately evaluate the health status of the axial piston pump.
In this paper, a finger rehabilitation robot with flexion/extension function is developed. This device consists of a four-finger mechanism and a thumb mechanism. The four-finger mechanism is modular designed, and cons...
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