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Full-Text Articles in Science and Technology Studies

Analysis Of A Chemostat Model With Variable Yield Coefficient And Substrate Inhibition: Contois Growth Kinetics, Rubayyi Turki Alqahtani, Mark I. Nelson, Annette L. Worthy Jan 2015

Analysis Of A Chemostat Model With Variable Yield Coefficient And Substrate Inhibition: Contois Growth Kinetics, Rubayyi Turki Alqahtani, Mark I. Nelson, Annette L. Worthy

Faculty of Engineering and Information Sciences - Papers: Part A

2015, Copyright Taylor & Francis Group, LLC. We analyze the steady-state operation of a generalized reactor model that encompasses a continuous flow bioreactor and an idealized continuous flow membrane reactor as limiting cases. The biochemical reaction kinetics is governed by a Contois growth model subject to noncompetitive substrate inhibition with a variable substrate yield coefficient. The steady-state performance of the reactor is predicted and stability of the steady-state solutions as a function of dimensionless residence time reported. Our results identified two cases of practical interest. The first feature corresponds to the case where solutions to both no-washout and washout conditions …


Large Piezoelectric Coefficient And Ferroelectric Nanodomain Switching In Ba(Ti0.80zr0.20)O3-0.5(Ba0.70ca 0.30)Tio3 Nanofibers And Thin Films, A Jalalian, A Grishin, Xiaolin Wang, Zhenxiang Cheng, S X. Dou Oct 2014

Large Piezoelectric Coefficient And Ferroelectric Nanodomain Switching In Ba(Ti0.80zr0.20)O3-0.5(Ba0.70ca 0.30)Tio3 Nanofibers And Thin Films, A Jalalian, A Grishin, Xiaolin Wang, Zhenxiang Cheng, S X. Dou

Shi Xue Dou

Currently available low-dimensional piezoelectric materials show a low piezoelectric coefficient d33 of merely 100 pm V-1 with Pb(Zr, Ti)O3-based materials at the high end. Here, we report very large piezoelectricity in Ba(Ti0.80Zr0.20)O 3-0.5(Ba0.70Ca0.30)TiO3 (BTZ-0.5BCT) lead-free nanostructures sintered as thin films (d33 = 140 pm V -1) and nanofibers (d33 = 180 pm V-1). The influences of lateral size, geometry, and the clamping effect on the piezoelectric performance were investigated for both thin films and nanofibers. Combining a high piezoelectric coefficient with environmental benefits, the BTZ-0.5BCT nanostructures provide the superior functions sought for highly efficient piezoelectric devices and electromechanical systems. 2014 …


Large Piezoelectric Coefficient And Ferroelectric Nanodomain Switching In Ba(Ti0.80zr0.20)O3-0.5(Ba0.70ca 0.30)Tio3 Nanofibers And Thin Films, A Jalalian, A Grishin, Xiaolin Wang, Zhenxiang Cheng, S X. Dou Jan 2014

Large Piezoelectric Coefficient And Ferroelectric Nanodomain Switching In Ba(Ti0.80zr0.20)O3-0.5(Ba0.70ca 0.30)Tio3 Nanofibers And Thin Films, A Jalalian, A Grishin, Xiaolin Wang, Zhenxiang Cheng, S X. Dou

Faculty of Engineering and Information Sciences - Papers: Part A

Currently available low-dimensional piezoelectric materials show a low piezoelectric coefficient d33 of merely 100 pm V-1 with Pb(Zr, Ti)O3-based materials at the high end. Here, we report very large piezoelectricity in Ba(Ti0.80Zr0.20)O 3-0.5(Ba0.70Ca0.30)TiO3 (BTZ-0.5BCT) lead-free nanostructures sintered as thin films (d33 = 140 pm V -1) and nanofibers (d33 = 180 pm V-1). The influences of lateral size, geometry, and the clamping effect on the piezoelectric performance were investigated for both thin films and nanofibers. Combining a high piezoelectric coefficient with environmental benefits, the BTZ-0.5BCT nanostructures provide the superior functions sought for highly efficient piezoelectric devices and electromechanical systems. 2014 …


Comparative Study Of Vehicle Tyre-Road Friction Coefficient Estimation With A Novel Cost-Effective Method, Boyuan Li, Haiping Du, Weihua Li Jan 2014

Comparative Study Of Vehicle Tyre-Road Friction Coefficient Estimation With A Novel Cost-Effective Method, Boyuan Li, Haiping Du, Weihua Li

Faculty of Engineering and Information Sciences - Papers: Part A

This paper qualitatively and quantitatively reviews and compares three typical tyre-road friction coefficient estimation methods, which are the slip slope method, individual tyre force estimation method and extended Kalman filter method, and then presents a new cost-effective tyre-road friction coefficient estimation method. Based on the qualitative analysis and the numerical comparisons, it is found that all of the three typical methods can successfully estimate the tyre force and friction coefficient in most of the test conditions, but the estimation performance is compromised for some of the methods during different simulation scenarios. In addition, all of these three methods need global …


A Novel Cost Effective Method For Vehicle Tire-Road Friction Coefficient Estimation, Boyuan Li, Haiping Du, Weihua Li Jan 2013

A Novel Cost Effective Method For Vehicle Tire-Road Friction Coefficient Estimation, Boyuan Li, Haiping Du, Weihua Li

Faculty of Engineering and Information Sciences - Papers: Part A

The tire-road friction coefficient is critical to vehicle longitudinal, lateral and roll dynamics and control because tire is the only contact part between the vehicle body and the road. However, direct measurement of tire-road friction coefficient is impossible in practice. This paper presents a novel cost effective method for vehicle tire-road friction coefficient estimation. This method only needs the measurements of the wheel angular velocity, the traction/brake torque and the longitudinal acceleration, which are all available from the commonly installed sensors in ordinary passenger vehicles, and can be used to estimate the individual tire-road friction coefficient. There are three steps …