An improved optimization method is proposed which combines the particle swarm (PSO) algorithm with dimension reduction kriging surrogate model (DK), namely PSO + DK. In this method, a dynamically constructed and updated between lower dimensional principal components response, instead of high-dimensional design variables response as in traditional methods. The key point DK that analysis (PCA) integrated active learning (AK). Since PCA can reduce effectively, makes construction possible for...

The main focus of this work is the successful deposition hard and wear-resistant TiAlCN coating on surface GCr15 bearing steel by means magnetron sputtering technology. phase composition chromium nitride transition layer was monitored precisely controlling nitrogen (N2) flow rate to strengthen bonding between surface. It found that performance reached optimal state at a N2 40 sccm, yielding hardness 23.3 GPa, friction coefficient only 0.27, wear 0.19 × 10−8 mm3/N·m.

This paper develops a method for the time-dependent reliability analysis of deteriorating structures using phase-type (PH) distributions. The model consists two aspects: progressive deterioration posed by aging effects, and shock caused random shocks. Evaluating distribution sum variables is tough work in model. For simplified problems that follow specific distributions with convolutions being derived analytically, it effective to utilize semianalytical methods analysis. other general (the...

An accurate dynamic 3D deformation measurement method realized by the combination of phase-shifting speckle interferometry and correlation is proposed. By converting field reference into a circular polarized linear state, three-step interferograms one specklegram were recorded directly simultaneously within single image using polarization camera. Then, out-of-plane was demodulated from synchronous fringe patterns, in-plane measured performing calculations specklegrams with effect ignored....

Reliability analysis methods such as active learning Kriging surrogate model combined with simulation-based have been paid much attention in recent years. These techniques can reduce the computational cost to a certain extent. However, burden may still be heavy for complex engineering problems. To address these issues, Kriging-based important region sampling method is proposed efficient reliability analysis. The new an improvement on original combining and Monte Carlo simulation (AK-MCS),...

In the life cycle of a long-life structure, multiple maintenances are often required to ensure safety or normal performance. This article developed multi-mission selective maintenance optimization model for system with several multistate components over finite time horizon. The aims minimize total cost by determining optimal intervention and corresponding option each component. reliability requirement is taken as constraint. degradation process component characterized homogeneous continuous...

Time-dependent reliability analysis remains challenging in practical engineering applications, since the modeling and solution are complicated, resulting huge computational burden. The composite limit state (CLS) method can efficiently reduce cost to a certain extent. However, is still high. In this article, an improved (ICLS) proposed for efficient time-dependent analysis, which based on original CLS. We propose two enhancements improve efficiency of ICLS approach. First, different from...

Compared with a constant stiffness (CS) composite structure of traditional straight fiber path, variable (VS) curvilinear path has broader design space. Taking the performance CS cylinder as baseline, two curved formats VS cylinders are investigated. One is that angle varies in circumferential direction (i.e., variation, VS-C), other both and axial directions variation,VS-CA). Non-uniform rational B-spline curve/surface used to define continuously varying orientation angle, making come true....

Due to its high power, efficiency, low pollution, and compact size, permanent magnet synchronous motors (PMSMs) have been widely used in a variety of fields, including electric vehicles, aerospace, wind turbines, marine devices which are renewable, sustainable, environmentally friendly energy resources. However, these practical scenarios, the motor operating conditions complex variable. Under temperatures current conditions, PMSMs may experience demagnetization failures, not only leading...

The Laplacian spectrum significantly contributes the study of structural features non-regular networks. Actually, it emphasizes interaction among network eigenvalues and their properties. Let

It remains a significant challenge to quantitatively describe the corrosion of reinforced concrete (RC) structures under chloride penetration. Moreover, when considering uncertainties throughout life cycle corroded RC for assessing their safety, reliability, and optimal design, complexity problem intensifies. To address these issues, this paper studies time-dependent reliability analysis design beams. At first, beams is investigated by both serviceability limit state (SLS), which corresponds...

It remains a grand challenge to handle time-dependent system reliability with stochastic process due the complexity and high computational cost. In this work, new phase-type (PH) distribution-based method is proposed for analysis. The PH strategy incorporated adaptive Kriging (AK) surrogate model make up PH-AK method. stage, main concern of obtain extreme value distribution process, which approximated as random variable distribution. Moreover, time parameter treated uniform variable....

Performance and reliability of structures will deteriorate with the effects loads, environment, interior factors materials. In this article, a novel cumulative damage model is developed for time-dependent analysis deteriorating structures. The deterioration combination three stochastic processes: gradual posed by aging effects, sudden caused transient additional introduced sustained loads. effect modeled as gamma process, while load described Poisson process. stationary binomial process...

Abstract Phase unwrapping plays an important role in optical phase measurements. In particular, under heavy noise conditions remains open issue. this paper, a deep learning-based method is proposed to conduct the task by combining Zernike polynomial fitting and Swin-Transformer network. method, regarded as regression problem, network used map relationship between wrapped data coefficients. Because of self-attention mechanism transformer network, coefficients can be estimated accurately even...

It remains an important challenge to quantitatively describe the corrosion of reinforced concrete (RC) structures under chloride penetration. When considering uncertainties encountered throughout life cycle RC exposed a corrosive environment and evaluating their safety reliability, complexity problem intensifies. To address these issues, this paper focuses on time-dependent reliability analysis corroded beams, utilizing phase-type (PH) fitting method. Initially, model for beams is...