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Arousal And Activation Effects On Physiological And Behavioral Responding During A Continuous Performance Task, Jacqueline A. Rushby, Robert J. Barry, Adam R. Clarke, Mohammad Vaezmousavi Jan 2007

Arousal And Activation Effects On Physiological And Behavioral Responding During A Continuous Performance Task, Jacqueline A. Rushby, Robert J. Barry, Adam R. Clarke, Mohammad Vaezmousavi

Faculty of Health and Behavioural Sciences - Papers (Archive)

Based on previous work indicating different neural substrates, two aspects of energetic state, arousal and activation, have been conceptualised separately in our laboratory. Arousal has been defined as the energetic state at any particular time, and task-related activation as the task-related change in state from resting baseline to the task situation. Both are reflected in electrodermal activity and measured by skin conductance level. Our previous studies in this area have indicated that physiological responses to stimuli in a task are dependent on the arousal level at the time of stimulus presentation, rather than the task-related activation. In contrast, performance on …


Reef Development At High-Latitudes During Multiple Interglacial Cycles: New Evidence From Lord Howe Island, Southwestern Pacific, David Kennedy, Colin D. Woodroffe, J -X Zhao Jan 2007

Reef Development At High-Latitudes During Multiple Interglacial Cycles: New Evidence From Lord Howe Island, Southwestern Pacific, David Kennedy, Colin D. Woodroffe, J -X Zhao

Faculty of Science - Papers (Archive)

Reef development during past Interglacial periods, when sea level and sea surface temperatures were higher than today, provide unique insights into how reef systems may respond to projected human-induced global warming. Lord Howe Island currently represents the southernmost limit of reef development in the Pacific. Reef growth of Pleistocene age has been inferred to have occurred around the island, and this paper provides the fi rst detailed descriptions on the character of this development. Two phases of reef growth are identifi ed, which occurred as isolated fringing reefs along the edge of the basaltic hills of the island. Uranium-series dating …


A Study Into The Use Of Computer Aided Assessment To Enhance Formative Assessment During The Early Stages Of Undergraduate Chemistry Courses, Simon B. Bedford, Gareth J. Price Jan 2007

A Study Into The Use Of Computer Aided Assessment To Enhance Formative Assessment During The Early Stages Of Undergraduate Chemistry Courses, Simon B. Bedford, Gareth J. Price

Faculty of Science, Medicine and Health - Papers: part A

A Virtual Learning Environment (WebCT and latter Moodle) was used to provide students with instant, meaningful feedback on their study of chemistry units during their first semester at University. Short multiple choice questions (MCQ's) were written covering each segment of material delivered in lectures and made available to students over the University computer intranet to allow "24/7" access. The most important aspect of the work was the feedback offered to students within the questions, which was written by undergraduate students to ensure its usefulness. The vast majority of the cohort used the MCQ's, most to gain formative feedback and some …


Observations Of The Mineral Matter Present At The Coke /Iron Interface During Coke Dissolution, Michael Chapman, Brian J. Monaghan, Sharon A. Nightingale, John G. Mathieson, Robert J. Nightingale Jan 2007

Observations Of The Mineral Matter Present At The Coke /Iron Interface During Coke Dissolution, Michael Chapman, Brian J. Monaghan, Sharon A. Nightingale, John G. Mathieson, Robert J. Nightingale

Faculty of Engineering - Papers (Archive)

In this study, the mineral matter layer that forms between coke, and liquid iron during carbon dissolution has been characterised. Rectangular prisms of coke were immersed in an iron–2 mass% carbon melt at representative ironmaking temperatures for 20 min then drop quenched. The quench sample was then sectioned and the coke–iron interface was examined in the SEM. A mineral matter layer was observed at the experimental temperatures 1 400°C, 1 450°C and 1 500°C, but not at 1 550°C. Though no layer was found at 1 550°C a slag was observed on the metal surface. This slag was not evident …


Mathematical Model To Predict Solids Content Of Water Treatment Residuals During Drying, Ali Gharaibeh, Muttucumaru Sivakumar, Dharmappa Hagare Jan 2007

Mathematical Model To Predict Solids Content Of Water Treatment Residuals During Drying, Ali Gharaibeh, Muttucumaru Sivakumar, Dharmappa Hagare

Faculty of Engineering - Papers (Archive)

Dewatering and drying of residuals are extremely energy intensive processes, which are necessary to reduce the quantity of wet residuals produced from the water and wastewater treatment operations. Meteorological conditions are a major factor in the drying of residuals, which can greatly affect the drying period. A mathematical model is developed for the process of drying of water treatment residuals. A steady-state heat-balance equation is applied for a control volume of residuals that takes into account the heat transfer by radiation, convection, and evaporation. The mathematical model was validated using drying experiments conducted in a wind tunnel as well as …


Effect Of High Pressure During The Fabrication On The Thermal And Mechanical Properties Of Amorphous Ni60nb40 Particle-Reinforced Al-Based Metal Matrix Composites, Peng Yu, Shankar Venkataraman, Jayanta Das, Laichang Zhang, Wenyong Zhang, Jurgen Eckert Jan 2007

Effect Of High Pressure During The Fabrication On The Thermal And Mechanical Properties Of Amorphous Ni60nb40 Particle-Reinforced Al-Based Metal Matrix Composites, Peng Yu, Shankar Venkataraman, Jayanta Das, Laichang Zhang, Wenyong Zhang, Jurgen Eckert

Faculty of Engineering - Papers (Archive)

Ni60Nb40 metallic glass particles, prepared by mechanical alloying, were used to fabricate Al–30 wt% Ni60Nb40 metal matrix composites (MMCs) at 823 K by sintering, hot pressing, and hot extrusion. The Ni60Nb40 reinforcements remained amorphous in all the MMCs fabricated by the different methods. Compression tests revealed that the Young’s modulus and yield strength of the MMCs produced by hot-pressing and hot-extrusion are higher than those for the sintered specimens. Differential scanning calorimeter (DSC) annealing of the as-produced MMCs at 913 K revealed there are severe interfacial reactions between the Al matrix …


The Role Of Achievement Goal Orientation In The Development Of Self Efficacy During Computer Training, Anura Rohan Jayasuriya, Peter Caputi, Parri Gregory, Joseph A. Meloche Jan 2007

The Role Of Achievement Goal Orientation In The Development Of Self Efficacy During Computer Training, Anura Rohan Jayasuriya, Peter Caputi, Parri Gregory, Joseph A. Meloche

Faculty of Health and Behavioural Sciences - Papers (Archive)

Computer self-efficacy (CSE) is a key factor that is related to performance in computer training. A study was conducted to understand the effects of achievement goal orientation on computer self efficacy development with 166 trainees using a database application. Results show that trainees with different achievement motivation dispositions have affects on CSE development through different paths. Individuals with high mastery approach and performance approach dispositions have positive effects on pre training CSE. Mastery avoidance disposition increases Computer Anxiety (CA), this is not seen with performance avoidance. Performance approach affects CSE development by increasing effort. The study provides initial evidence for …


Numerical Simulation Of Temperature Field And Thermal Stress Field Of Work Roll During Hot Strip Rolling, Chang-Sheng Li, Hai-Liang Yu, Guan-Yu Deng, Xiang-Hua Liu, Guo-Dong Wang Jan 2007

Numerical Simulation Of Temperature Field And Thermal Stress Field Of Work Roll During Hot Strip Rolling, Chang-Sheng Li, Hai-Liang Yu, Guan-Yu Deng, Xiang-Hua Liu, Guo-Dong Wang

Faculty of Engineering and Information Sciences - Papers: Part A

Based on the thermal conduction equations, the three-dimensional (3D) temperature field of a work roll was investigated using finite element method (FEM). The variations in the surface temperature of the work roll during hot strip rolling were described, and the thermal stress field of the work roll was also analyzed. The results showed that the highest roll surface temperature is 593 °C, and the difference between the minimum and maximum values of thermal stress of the work roll surface is 145. 7 MPa. Furthermore, the results of this analysis indicate that temperature and thermal stress are useful parameters for the …


Influence Of Dog-Bone Apex On Shape During Slab Horizontal Rolling Process, Hai-Liang Yu, Xiang-Hua Liu, Chang-Sheng Li, Guo-Dong Wang Jan 2007

Influence Of Dog-Bone Apex On Shape During Slab Horizontal Rolling Process, Hai-Liang Yu, Xiang-Hua Liu, Chang-Sheng Li, Guo-Dong Wang

Faculty of Engineering and Information Sciences - Papers: Part A

The deformation of slab with dog-bone shape during the horizontal rolling process was simulated using FEM, and the influences of apical dislocation of dog-bone on the slab spread as well as the minimum crop end loss and the lost width at slab head and tail were analyzed. The results show that with the increase in the apical dislocation of dog-bone (LA), the slab spread and the minimum crop end loss at slab head and tail decrease, while the lost width at slab head and tail increases. Meanwhile, the relationships of S/LA-LA, LH/LA-LA, WH/LA-LA, LT/LA-LA, and WT/LA-LA were obtained. © 2007 …


Influence Of Microalloying Precipitates On Bauschinger Effect During Uoe Forming Of Line Pipe Steels, Andrii Kostryzhev, Martin Strangwood, Claire L. Davis Jan 2007

Influence Of Microalloying Precipitates On Bauschinger Effect During Uoe Forming Of Line Pipe Steels, Andrii Kostryzhev, Martin Strangwood, Claire L. Davis

Faculty of Engineering and Information Sciences - Papers: Part A

Large diameter steel line pipes are generally produced by cold deforming hot rolled or thermomechanically controlled rolled (TMCR) plate by the three-stage 'UOE' process. Pipe strength has been found to increase or decrease relative to the plate, depending on the steel grade and plate processing history. The strength increase is due to work hardening whereas any decrease in strength arises from the Bauschinger effect due to the reverse cold deformation of the UOE process. The steel chemistry, through the presence of strengthening microalloy precipitates, and prior processing, through the size and distribution of microalloy precipitates and the presence of retained …


Texture Evolution During Annealing Of Warm Rolled Cr-Containing Low Carbon Steels, E V. Pereloma, Azdiar A. Gazder, John J. Jonas, Chris H. J. Davies Jan 2007

Texture Evolution During Annealing Of Warm Rolled Cr-Containing Low Carbon Steels, E V. Pereloma, Azdiar A. Gazder, John J. Jonas, Chris H. J. Davies

Faculty of Engineering - Papers (Archive)

Two low carbon steels alloyed with 0.48wt% and 0.78wt% Cr were warm rolled to 65% reduction at 640°C. Annealing was carried out at 710°C to achieve a range of recrystallized volume fractions up to 100%. Texture analysis was performed by X-ray diffraction and Electron Back Scattering Diffraction. During the initial stages of recrystallization, more recrystallized grains nucleated at shear bands than at grain boundaries in the 0.48wt%Cr steel, whereas this was not the case in the 0.78wt%Cr steel. This is associated with a decrease in the propensity to form shear bands due to the lower amount of C in solid …