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Full-Text Articles in Science and Technology Studies

Characterisation Of Coke Packed Beds After Liquid Slag Flow At 1 500°C By Image Analysis, Hazem Labib George, Raymond Longbottom, Sheng Chew, David Pinson, Brian Monaghan Jan 2014

Characterisation Of Coke Packed Beds After Liquid Slag Flow At 1 500°C By Image Analysis, Hazem Labib George, Raymond Longbottom, Sheng Chew, David Pinson, Brian Monaghan

Faculty of Engineering and Information Sciences - Papers: Part A

The flow of slag in the lower zone of the ironmaking blast furnace was experimentally simulated by adding slag to a high temperature laboratory scale coke packed bed. The flow of slag through packed beds of coke with packing densities varying from 50% to 65% was examined at 1 500°C. Since the liquid flow through a packed bed depends on packing properties such as particle size, particle shape, pore size and pore neck size, it was necessary to characterise these properties of the beds. In this work, image analysis of successive sections of the tested beds was utilised to characterise …


Effects Of Temperature And Strain Rate On Microstructure And Mechanical Properties Of High Chromium Cast Iron/Low Carbon Steel Bimetal Prepared By Hot Diffusion-Compression Bonding, Xingjian Gao, Zhengyi Jiang, Dongbin Wei, Sihai Jiao, Dengfu Chen, Jianzhong Xu, Xiaoming Zhang, Dianyao Gong Jan 2014

Effects Of Temperature And Strain Rate On Microstructure And Mechanical Properties Of High Chromium Cast Iron/Low Carbon Steel Bimetal Prepared By Hot Diffusion-Compression Bonding, Xingjian Gao, Zhengyi Jiang, Dongbin Wei, Sihai Jiao, Dengfu Chen, Jianzhong Xu, Xiaoming Zhang, Dianyao Gong

Faculty of Engineering and Information Sciences - Papers: Part A

The objective of this study is to develop a hot diffusion-compression bonding process for cladding low carbon steel (LCS) to high chromium cast iron (HCCI) in solid-state. The influence of temperature (950-1150 degrees C) and strain rate (0.001-1 s (1)) on microstructure, hardness and bond strength of the HCCI/LCS bimetal were investigated. The interface microstructure reveals that the unbonded region can only be found for 950 degrees C due to lack of diffusion, while the intergrowth between the constituent metals occurred at and above 1100 degrees C. When bonding temperature increases to 1150 degrees C, a carbide-free zone was observed …


A Multifeature-Based Approach For Islanding Detection Of Dg In The Subcritical Region Of Vector Surge Relays, Mollah R. Alam, Kashem M. Muttaqi, Abdesselam Bouzerdoum Jan 2014

A Multifeature-Based Approach For Islanding Detection Of Dg In The Subcritical Region Of Vector Surge Relays, Mollah R. Alam, Kashem M. Muttaqi, Abdesselam Bouzerdoum

Faculty of Engineering and Information Sciences - Papers: Part A

Anti-islanding protection is an important requirement which has to be considered prior to the integration of distributed generation into electricity grids. Conventional vector surge (VS) relays are usually used to detect islanding; however, there is a nondetection zone (NDZ) wherein islanding incidents are undetectable by VS relays. This paper proposes a multifeature-based technique for islanding detection in the subcritical region, defined as a subregion of the NDZ. In the proposed method, features are extracted from five network variables. The extracted features are then used as inputs to a support vector machine to classify the event as islanding or nonislanding. A …


Optimal Adaptive Wireless Body Area Networks For High Speed In Health Services, Miftadi Sudjai, Le Chung Tran, Farzad Safaei, Son Lam Phung Jan 2014

Optimal Adaptive Wireless Body Area Networks For High Speed In Health Services, Miftadi Sudjai, Le Chung Tran, Farzad Safaei, Son Lam Phung

Faculty of Engineering and Information Sciences - Papers: Part A

Adaptive ultra-wideband wireless body area networks have been proposed as one of feasible mHealth platforms offering a high-speed, robust mobile health service. The error performance of such sytems outperforms non-adaptive systems by up to 4 dB. To further improve the error performance, the optimization of adaptive parameters is investigated in this paper. Simulation results show that the proposed optimal adaptive systems achieves a 2 dB gain with respect to bit error rate (BER). This improvement is equivalent to extra reduction of the power consumption up to 37% in these networks, thus increasing the longevity and reliability of mHealth services.


Characterisation Of Gas Turbine Dynamics During Frequency Excursions In Power Networks, Lasantha Meegahapola Jan 2014

Characterisation Of Gas Turbine Dynamics During Frequency Excursions In Power Networks, Lasantha Meegahapola

Faculty of Engineering and Information Sciences - Papers: Part A

Gas turbines inherently depict unique frequency response characteristics compared with other conventional synchronous generation technologies as their active power output is not entirely determined by the governor response during frequency deviations of the power network. Thus, gas turbine dynamics significantly influence on system stability during frequency events in power networks. Power system and power plant operators require improved understanding of the gas turbine characteristics during various frequency events in order to mitigate adverse impact on power system. Therefore a comparative analysis has been performed between combined-cycle gas turbines (CCGTs) and open-cycle gas turbines (OCGTs) in order to characterise the dynamic …


An Effective Localization Method For Robotic Endoscopic Capsules Using Multiple Positron Emission Markers, Trung Duc Than, Gursel Alici, Steven Harvey, Graeme O'Keefe, Hao Zhou, Weihua Li, Trent Cook, Sharon Alam-Fotias Jan 2014

An Effective Localization Method For Robotic Endoscopic Capsules Using Multiple Positron Emission Markers, Trung Duc Than, Gursel Alici, Steven Harvey, Graeme O'Keefe, Hao Zhou, Weihua Li, Trent Cook, Sharon Alam-Fotias

Faculty of Engineering and Information Sciences - Papers: Part A

The wireless capsule endoscope (WCE) is a first-line medical tool for the diagnosis of many gastrointestinal (GI) tract diseases such as obscure GI bleeding, Crohn's disease, small bowel tumors, and Celiac disease. Over the past few years, significant research attention has been paid to upgrading the WCE from a diagnostic-only tool to an active medical robot having not only diagnostic capabilities but therapeutic functionalities, such as biopsy, microsurgery, and targeted drug delivery, as well. One of the major limitations that impedes the development of such a robotic-type endoscope is the lack of a highly accurate localization system. In this paper, …


Numerical Modelling Of The Groundwater Inflow To An Advancing Open Pit Mine: Kolahdarvazeh Pit, Central Iran, Saeed Bahrami, Faramarz Doulati Ardejani, Soheyla Aslani, Ernest Baafi Jan 2014

Numerical Modelling Of The Groundwater Inflow To An Advancing Open Pit Mine: Kolahdarvazeh Pit, Central Iran, Saeed Bahrami, Faramarz Doulati Ardejani, Soheyla Aslani, Ernest Baafi

Faculty of Engineering and Information Sciences - Papers: Part A

The groundwater inflow into a mine during its life and after ceasing operations is one of the most important concerns of the mining industry. This paper presents a hydrogeological assessment of the Irankuh Zn-Pb mine at 20 km south of Esfahan and 1 km northeast of Abnil in west-Central Iran. During mine excavation, the upper impervious bed of a confined aquifer was broken and water at high-pressure flowed into an open pit mine associated with the Kolahdarvazeh deposit. The inflow rates were 6.7 and 1.4 m3/s at the maximum and minimum quantities, respectively. Permeability, storage coefficient, thickness and initial head …


Identity-Based Chameleon Hashing And Signatures Without Key Exposure, Xiaofeng Xiaofeng Chen, Fangguo Zhang, Willy Susilo, Haibo Tian, Jin Li, Kwangjo Kim Jan 2014

Identity-Based Chameleon Hashing And Signatures Without Key Exposure, Xiaofeng Xiaofeng Chen, Fangguo Zhang, Willy Susilo, Haibo Tian, Jin Li, Kwangjo Kim

Faculty of Engineering and Information Sciences - Papers: Part A

The notion of chameleon hash function without key exposure plays an important role in designing secure chameleon signatures. However, all of the existing key-exposure free chameleon hash schemes are presented in the setting of certificate-based systems. In 2004, Ateniese and de Medeiros questioned whether there is an efficient construction for identity-based chameleon hashing without key exposure. In this paper, we propose the first identity-based chameleon hash scheme without key exposure based on the three-trapdoor mechanism, which provides an affirmative answer to the open problem. Moreover, we use the proposed chameleon hash scheme to design an identity-based chameleon signature scheme, which …


Mri Distortion: Considerations For Mri Based Radiotherapy Treatment Planning, Amy Walker, Gary P. Liney, Peter E. Metcalfe, Lois Holloway Jan 2014

Mri Distortion: Considerations For Mri Based Radiotherapy Treatment Planning, Amy Walker, Gary P. Liney, Peter E. Metcalfe, Lois Holloway

Faculty of Engineering and Information Sciences - Papers: Part A

Distortion in magnetic resonance images needs to be taken into account for the purposes of radiotherapy treatment planning (RTP). A commercial MRI grid phantom was scanned on 4 different MRI scanners with multiple sequences to assess variations in the geometric distortion. The distortions present across the field of view were then determined. The effect of varying bandwidth on image distortion and signal to noise was also investigated. Distortion maps were created and these were compared to the location of patient anatomy within the scanner bore to estimate the magnitude and distribution of distortions located within specific clinical regions. Distortion magnitude …


The Effect Of Ageing On Microstructure And Mechanical Properties Of Powder Ti-5al-5mo-5v-1cr-1fe Alloy, Mansur Ahmed, Dmytro Savvakin, Orest M. Ivasishin, E V. Pereloma Jan 2014

The Effect Of Ageing On Microstructure And Mechanical Properties Of Powder Ti-5al-5mo-5v-1cr-1fe Alloy, Mansur Ahmed, Dmytro Savvakin, Orest M. Ivasishin, E V. Pereloma

Faculty of Engineering and Information Sciences - Papers: Part A

The thermo-mechanically processed powder Ti-5Al-5V-5Mo-1Cr-1Fe alloy was aged at 9.23 K for 1-8 h in order to investigate the effect of ageing time on the microstructure-mechanical properties relationships. The microstructures of the alloy after ageing cosist of the both primary and secondary alpha phases with retained B matrix phase. The shift of B peaks in X-ray pattern with ageing time indicates an increase in lattice parameter distorition due to diffusion into the retained B phase of more B stabilisers with smaller atomic radius compared to the elemental Ti. The tensile test results indicate that the sample aged for 1 h …


Purely Infinite Partial Crossed Products, Thierry Giordano, Adam Sierakowski Jan 2014

Purely Infinite Partial Crossed Products, Thierry Giordano, Adam Sierakowski

Faculty of Engineering and Information Sciences - Papers: Part A

Let (A, G, alpha) be a partial dynamical system. We show that there is a bijective corespondence between G-invariant ideals of A and ideals in the partial crossed prroduct A xalpha, r G provided the action is exact and residually topologically free.


Investigating The Optimal Passive And Active Vibration Controls Of Adjacent Buildings Based On Performance Indices Using Genetic Algorithms, Muhammad N. S Hadi, Mehmet Uz Jan 2014

Investigating The Optimal Passive And Active Vibration Controls Of Adjacent Buildings Based On Performance Indices Using Genetic Algorithms, Muhammad N. S Hadi, Mehmet Uz

Faculty of Engineering and Information Sciences - Papers: Part A

This study proposes the optimal passive and active damper parameters for achieving the best results in seismic response mitigation of coupled buildings connected to each other by dampers. The optimisation to minimise the H2 and H- norms in the performance indices is carried out by genetic algorithms (GAs). The final passive and active damper parameters are checked for adjacent buildings connected to each other under El Centro NS 1940 and Kobe NS 1995 excitations. Using real coded GA in H- norm, the optimal controller gain is obtained by different combinations of the measurement as the feedback for designing the control …