The first-order reliability method (FORM) is efficient but may not be accurate for nonlinear limit-state functions. second-order (SORM) more less efficient. To maintain both high accuracy and efficiency, we propose a new analysis with efficiency. first performs the FORM to identify most probable point (MPP). Then, associated function decomposed into additive univariate functions at MPP. Each further approximated by quadratic function. cumulant generating of then available so that saddlepoint...

A function generator mechanism links its motion output and input with a desired functional relationship. The probability of realizing such relationship is the kinematic reliability. time-dependent reliability because it provides over time interval where defined. But methodologies are currently lacking for mechanisms. We propose mean value first-passage method analysis. With assumption normality random dimension variables small variances, error becomes nonstationary Gaussian process. at first...

The widely used First Order Reliability Method (FORM) is efficient, but may not be accurate for nonlinear limit-state functions. Second (SORM) more less efficient. To maintain both high accuracy and efficiency, we propose a new second order reliability analysis method with first efficiency. performs the FORM identifies Most Probable Point (MPP). Then associated function decomposed into additive univariate functions at MPP. Each further approximated as quadratic function, which created...

Roller shapes play a very critical role in the performance of antibacklash double-roller enveloping hourglass worm (ADEHW) gears; however, their influence is seldom reported literature. Based on theories differential geometry and gear meshing, this paper presents generic models meshing characteristics for ADEHW gears, including both contact curve tooth profile. We present different functions derivatives with respect to each drive type associated roller shapes. also compare effects curve,...

In practical scenarios, journal bearings often exhibit shape errors due to machining imperfections and operational wear. These deviations from perfect roundness can significantly impact the performance of during start-up. This study investigates on transient mixed lubrications, such as water film temperature asperity contact, well rotor dynamics water-lubricated (WLB) at The simulation results developed numerical model are compared with experimental data existing studies verify their...

ABSTRACT The aim of this study is to better enable students grasp the complex material science involved in engine casting, address various engineering challenges, gain precise control casting process, strengthen their practical skills, and enhance effectiveness teaching forging. Firstly, on basis real forging production, complete 3D modeling each production line carried out using 3dsMax software. Then, finished models are imported into virtual simulation software Unity3D arrange layouts...

Abstract Aero‐engine turbine blades are subject to combined high and low cycle fatigue (CCF) loadings during operations. In this paper, a modified nonlinear cumulative damage model is developed based on linear accumulation theory static toughness exhaustion predict the CCF life of common blade materials. An interaction factor created reflect integrated effect (HCF‐LCF). Available test data from TC4 alloy other two materials, together with utilized validate robustness accuracy proposed...

Simultaneous detection of various o ‐phthalaldehyde (OPA)‐labeled amino acids (AAs) in food samples was reported based on CE separation. Ionic liquid used for the first time analysis AAs with in‐capillary derivatization. Several other additives, including SDS, α/β‐CD, and ACN, as well key parameters separation (buffer pH value, voltage), were also investigated. Our results show that multiple additive strategy exhibits good stable repeatable character OPA‐labeled AAs, either derivatization or...

Fatigue life estimation of aero-engine turbine components under combined high and low cycle fatigue (CCF) is significance for guaranteeing the structural reliability during operation. According to investigations on damage evolution process, a nonlinear accumulation method proposed prediction CCF loadings, interaction effect between (HCF) (LCF) considered by integrating factor stress ratio CCF. Furthermore, experimental results alloys blades are utilized validate conduct comparative analysis...

Aiming at the acoustic attenuation in salt-cavern environment, this paper established a theoretical relationship of ultrasonic gas storage, based on wave equation propagating non-ideal medium, and considering specific environment analyzes how wall roughness storage affects attenuation. The results show that inner has an effect surface is solid-liquid interface, where change medium will affect wave, effective reflection coefficient cause to attenuate lower frequency. On basis, characteristics...

A periodic intermittent adaptive control method with saturation is proposed to pin the quasi-consensus of nonlinear heterogeneous multi-agent systems external disturbances in this paper. new protocol designed internal coupling between follower agents and feedback gain leader follower. In particular, we use law: when error converges a certain range, edge weight will not be updated. Furthermore, propose three saturated pinning protocols. The achieved through its own as long remain connected...

Spherical mechanisms are widely used in engineering applications. Minimizing their motion error is critical for high performance of such mechanisms. The significantly affected by uncertainties spherical impact the on error, however, rarely considered mechanism analysis and synthesis. In this work, we quantify effects randomness major dimension variables through kinematic reliability with a probabilistic approach. Two types reliability, point interval discussed. For former First Order Second...

In this paper, a new kind of the anti-backlash double-roller enveloping hourglass worm (ADEHW) with line contact between intersecting axes has been studied by means theory gearing and space engagement for first time. The equation tooth profile have derived applying gearing. Meanwhile important factors that impact performances were numerical calculated analysis. Based on developed mathematical model Anti-backlash Double-roller Enveloping Hourglass worm, computer graph gear set designed...

The tooth contact parameters such as lubrication angle, induced normal curvature, entrainment velocity, et al. of the nonbacklash double-roller enveloping hourglass worm gearing and influencing factors are studied systematically. averages velocity roller's rotation angle which located on a number mesh lines taken meshing performance index. Based numerical computation, influences roller radius, installation offset distance, throat diameter coefficient drive center distance non-backlash...

This1 thesis presents a new method of Android application forensics, based on the heap memory analysis. In this method, data an app, running virtual machine, is directly extracted, parsed and reconstructed. The path target can be located depending exported testing data. Next, it designs steps extraction applies them in real forensics work. This discusses way searching targeting detail. It successfully acquires various records from data, including user's password hash, experiments...

The all-level <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">d</i> minimal path vectors ( xmlns:xlink="http://www.w3.org/1999/xlink">d-</i> MPs) are an important input for obtaining the performance metric of multistate networks, which is basis resilience evaluation and analysis. During process, network configurations may change, leading to changes in -MPs. However, when changed, repeated searching MPs time consuming because it NP-hard...

In order to improve wear resistance and rock breaking efficiency of single-roller bit, a new type PDC compound bit is designed. The mechanical model interaction between teeth established, the theoretical calculation formula resultant force torque generated by on cone obtained. rock-breaking experiment are carried out. results show that with increase front inclination angle, axial radial decrease greatly at first then tend be stable, while tangential decreases increases slightly; force, all...

Abstract The time-dependent kinematic reliability of a mechanism is the probability that motion error less than prespecified tolerance for given period time. For analysis, envelope method outperforms sampling (Monte Carlo simulation) because its higher efficiency. This study further enhances with improved accuracy. improvement achieved by keeping all expansion points in approximation limit-state function, some which are discarded original to avoid numerical singularity. A new equivalent...