Mechanical

Drilling force and temperature of bone under dry and physiological drilling conditions
Many researches on drilling force and temperature have been done with the aim to reduce the labour intensiveness of surgery, avoid unnecessary damage and improve drilling quality. However, there has not been a systematic study of mid- and high-speed drilling under dry and physiological conditions(injection of saline). Furthermore, there is no consensus on optimal drilling parameters. To study t...


Optimal design of multiple stresses accelerated life test plan based on transforming the multiple stresses to single stress
For planning optimum multiple stresses accelerated life test plans, a commonly followed guiding principle is that all parameters of the life-stress relationship should be estimated, and the number of the stress level combinations must be no less than the number of parameters of the life-stress relationship. However, the general objective of an accelerated life test(ALT) is to assess the p-th qu...
Sequential RBF surrogate-based efficient optimization method for engineering design problems with expensive black-box functions
As a promising technique, surrogate-based design and optimization(SBDO) has been widely used in modern engineering design optimizations. Currently, static surrogate-based optimization methods have been successfully applied to expensive optimization problems. However, due to the low efficiency and poor flexibility, static surrogate-based optimization methods are difficult to efficiently solve pr...


Coupling characteristics and control of dual mechanical port machine with spoke type permanent magnet arrangement
Dual mechanical port machine(DMPM), as a novel electromechanical energy conversion device, has attracted widespread attention. DMPM with spoke type permanent magnet arrangements(STPM-DMPM), which is one of several types of DMPM, has been of interest recently. The unique coupling characteristics of STPM-DMPM are beneficial to improving system performance, but these same characteristics increase ...
Influence of tire dynamics on slip ratio estimation of independent driving wheel system
The independent driving wheel system, which is composed of in-wheel permanent magnet synchronous motor(I-PMSM) and tire, is more convenient to estimate the slip ratio because the rotary speed of the rotor can be accurately measured. However, the ring speed of the tire ring doesn’t equal to the rotor speed considering the tire deformation. For this reason, a deformable tire and a detailed I-PM...


Electromagnetic characteristic of twin-wire indirect arc welding
Traditional welding methods are limited in low heat input to workpiece and high welding wire melting rate. Twin-wire indirect arc(TWIA) welding is a new welding method characterized by high melting rate and low heat input. This method uses two wires: one connected to the negative electrode and another to the positive electrode of a direct-current(DC) power source. The workpiece is an independen...
High-precision thickness setting models for titanium alloy plate cold rolling without tension
Due to its highly favorable physical and chemical properties, titanium and titanium alloy are widely used in a variety of industries. Because of the low output of a single batch, plate cold rolling without tension is the most common rolling production method for titanium alloy. This method is lack of on-line thickness closed-loop control, with carefully thickness setting models for precision. A...

Accounting for evolving pore size distribution in water retention models for compacted clays
Water retention in compacted clays is dominated by multi-modal pore size distribution which evolves during hydro-mechanical paths depending on water content and stress history. A description of the evolutionary fabric has been recently introduced in models for water retention, but mostly on a heuristic base. Here, a possible systematic approach to account for evolving pore size distribution is ...
Numerical modeling of toxic nonaqueous phase liquid removal from contaminated groundwater systems: mesh effect and discretization error estimation
Numerical modeling has now become an indispensable tool for investigating the fundamental mechanisms of toxic nonaqueous phase liquid (NAPL) removal from contaminated groundwater systems. Because the domain of a contaminated groundwater system may involve irregular shapes in geometry, it is necessary to use general quadrilateral elements, in which two neighbor sides are no longer perpendicular ...

Robotic System Development for Cooperative Orthopedic Drilling Assistance
This paper describes a robotic bone drilling and screwing system for applications in orthopedic surgery. The goal is to realize two robot manipulators performing cooperative bone drilling. The proposed cooperative bone drilling system can be divided into hardware and software development. The hardware development section consists of two robot manipulator arms, which perform drilling and grippin...
Study on the crack-inclusion interaction with coupled mechanical and thermal strains
The interaction between a Mode I crack and an inclusion in an infinite medium is examined with consideration of coupled mechanical and thermal loads under plane strain condition. A closed-form formula for the change of the stress intensity factor is obtained based on the transformation toughening theory and the Eshelby inclusion method. The mismatched thermal expansion strains between the inclu...

Stress Intensity Factors for Hypocycloidal Hole with Cusps in Infinite Anisotropic Plate
Using Muskhelishvili’s complex variable approach, general solution to calculate stress intensity factors (SIF) for hypocycloidal hole is obtained in infinite symmetric anisotropic plate. The stress functions are evaluated and numerical results are presented for Graphite/epoxy, Glass/Epoxy and isotropic material. The effect of stacking sequence, hole geometry, material properties and loading a...
Study on powertrain system for CNG-electric hybrid city bus
In order to obtain better economy and power performances of compressed natural gas (CNG) and electric hybrid city bus, the powertrain system is designed and studied in this paper. Based on manufacturing technology, operation cost and dynamic property, economy is regarded as the main optimization goal for CNG-electric hybrid city bus, which determines the structure of powertrain system of CNG-el...
A fatigue and low-energy shock-based approach to predict fatigue life
A product that is characterized by fatigue-induced failure always suffers from complex fatigue loads, and the damage caused by fatigue loads accumulates with time. The existence of shocks not only directly increases the risk of failure but also affects the magnitude of damage caused by fatigue loads. This study analyzes the reliability of a product when fatigue loads and shocks are both involve...
Transient performance prediction of an axial compressor considering VIGV operation speeds
In the present study, transient performance and flow characteristics of a 1.5-stage compressor with VIGV are investigated using CFD. The level of accuracy of CFD approach is evaluated by comparing the predicted performance against experimental data of a 3.5-stage compressor. The main objective of the present research is to quantitatively estimate the performance of transonic axial-flow compress...