Engineering Commons^™

Microstructural Characterisation And Mechanical Evaluation Of Ti-15mo Manufactured By Laser Metal Deposition, Edohamen Awannegbe, Huijun Li, Tingting Song, Frank Niessen, Ma Qian, Azdiar A. Gazder, Mitchell John Bromley Nancarrow, Elena V. Pereloma

Faculty of Engineering and Information Sciences - Papers: Part B

A bidirectional powder deposition strategy was employed to additively manufacture Ti-15Mo wt% using laser metal deposition. Phase identification, elemental analysis and microstructural characterisation were conducted after fabrication and uniaxial tensile testing using X-ray diffraction and scanning electron microscopy along the different processing directions. In addition, electron backscattering diffraction and transmission electron microscopy were used to analyse deformation mechanisms. It was found that three distinct zones, namely the fusion, remelted and heat affected zones, evolved in all 25 deposited layers which predominantly comprised coarse columnar grains. Mo segregation was pronounced in the as-built microstructure. Deformation accommodation in β matrix was by …

Thermal Effect During Laser-Induced Plasmonic Heating Of Polyelectrolyte-Coated Gold Nanorods In Well Plates, Sujin Jiracheewanun, Michael B. Cortie, Dakrong Pissuwan

Faculty of Engineering and Information Sciences - Papers: Part B

We examined the generation and transfer of heat when laser irradiation is applied to water containing a suspension of gold nanorods coated with different polyelectrolytes. The ubiquitous well plate was used as the geometry for these studies. The predictions of a finite element model were compared to experimental measurements. It is found that relatively high fluences must be applied in order to generate biologically relevant changes in temperature. This is due to the significant lateral heat transfer from the sides of the well, which strongly limits the temperature that can be achieved. A 650 mW continuous-wave (CW) laser, with a …

Finite Element Analysis Of Square Frp-Concrete-Steel Columns Under Eccentric Compression, Amin Izadi, Lip H. Teh, Aziz Ahmed, Maria Anna Polak

Faculty of Engineering and Information Sciences - Papers: Part B

This paper presents the development of a finite element (FE) methodology for investigating the behavior of the FRP, concrete and steel components of a square FRP-concrete-steel composite (FCSC) columns with a rotated square inner steel tube. The FE models are developed in ABAQUS using the authors’ recently refined Concrete Damage Plasticity Model (CDPM) in conjunction with the FRP damage criteria available in the literature. The developed FE methodology is verified against the authors’ experimental test results involving columns with normal and rotated square inner steel tubes under eccentric loading, and the FE analysis results are used to explain the …

Transtibial Prosthetic Socket Fitting: Australian Prosthetist Perspectives On Primary Challenges, Management Strategies, And Opportunities For Workflow And Technological Innovation, Lucy E. Armitage, Kirsty A. Mcdonald, Lauren Kark, Angela Buller, Belinda Ford

Faculty of Engineering and Information Sciences - Papers: Part B

Background: Following transtibial amputation, a custom-built socket is the most common interface between the prosthesis and residual limb. Desire from both prosthetists and prosthesis users for improved socket fitting processes have been well documented. However, there is currently limited information available about prosthetists’ experiences of how prosthetic manufacturing workflow can contribute to socket fit problems.

Objectives: This study aims to determine how socket fit problems are currently detected and managed by prosthetists and to identify challenges, management strategies, and opportunities for workflow and technological innovation during prosthesis manufacture and socket fitting.

Study design: Mixed-method (quantitative and qualitative) survey.

Methods: An …

Development Of A More Accurate Geant4 Quantum Molecular Dynamics Model For Hadron Therapy, Yoshi-Hide Sato, Dousatsu Sakata, David Bolst, Susanna Guatelli, Akihiro Haga

Faculty of Engineering and Information Sciences - Papers: Part B

Objective. Although in heavy-ion therapy, the quantum molecular dynamics (QMD) model is one of the most fundamental physics models providing an accurate daughter-ion production yield in the final state, there are still non-negligible differences with the experimental results. The aim of this study is to improve fragment production in water phantoms by developing a more accurate QMD model in Geant4. Approach. A QMD model was developed by implementing modern Skyrme interaction parameter sets, as well as by incorporating with an ad hoc α-cluster model in the initial nuclear state. Two adjusting parameters were selected that can significantly affect the fragment …

A Photographic Essay On Landslides Across Southeastern New South Wales Triggered By The Rainfall Events Of 2022, Phil Flentje, Connor Larkin, Damian Mulcahy, Larissa Hettiarachchi, Dan Horan, James Cox, Stuart Milling, Peter Tobin, Kevin Bogie

Faculty of Engineering and Information Sciences - Papers: Part B

Eastern Australia has experienced a significant magnitude rainfall event of extended duration in the first 7 months of 2022. Across the east coast of New South Wales (NSW) a series of troughs and East Coast Lows occurred during a La Nina weather cycle bringing above average rainfall to the region. As this first half of 2022 La Nina event was drawing to a close the Indian Ocean Dipole entered a negative phase which coincided with another intense East Coast Low in early July 2022 impacting the Illawarra region of NSW. These events caused widespread flooding and significant landslide damage to …

Optimum Auxiliary Fan Location To Control Air Recirculation, Ramakrishna Morla, Shivakumar Karekal, Ajit R. Godbole, Purushotham Tukkaraja, Ping Chang

Faculty of Engineering and Information Sciences - Papers: Part B

This paper presents the optimum auxiliary fan(s) location to control air recirculation in dead-end workings where diesel-powered vehicles operate. Investigations were conducted with various secondary fan locations from the dead-end crosscut with varying the intake air quantities using a 30 m³/s capacity twin 75 kW auxiliary fan and 45 m³/s capacity twin 110 kW auxiliary fan to control air recirculation and DPM. The results showed that if the drive intake airflow rate matches the fan capacity, air recirculation will occur even when the fan is located 10 m away from the crosscut entry. Results also showed …

Prehistoric Landslides: Significance, Recognition, Examples, James V. Hamel, David L. Knott, Phil Flentje, Stephen Fityus

Faculty of Engineering and Information Sciences - Papers: Part B

Prehistoric landslides with a wide range of ages and sizes exist worldwide in both rock and soil. Many are thought to have occurred during Pleistocene time when climates in some areas were harsher and wetter. Subsequent weathering and erosion have subdued topography and other features of prehistoric landslides, often making them difficult to recognize. Recognition is the key to dealing with prehistoric and other old landslides. Old slide masses are usually only marginally stable because past movements reduced available shear strength on their failure surfaces to residual levels. These masses are susceptible to reactivation by construction activities, heavy precipitation, and …

Bulli Pass Landslide Risk Management Part 1 – Hazard Assessment, Andrew Hunter, Phil Flentje, Alan Moon

Faculty of Engineering and Information Sciences - Papers: Part B

The Princes Highway along Bulli Pass is a narrow, heavily trafficked two lane section of the Princes Highway that traverses steep slopes on a grade of 9H:1V on the Illawarra Escarpment, about 11 km north of Wollongong, and 75 km south of Sydney in New South Wales (NSW), Australia. It is an important arterial road for the northern suburbs of Wollongong, connecting Mt Ousley Road (M1 Princes Motorway) at the crest of the escarpment to the suburb of Thirroul on the coastal plain at the base of the escarpment. Bulli Pass has a long history of landslide and rockfall events, …

Hygrothermal Performance Of Vapour-Permeable Wall Membranes In Cooler Australian Climates: Comparative Modelling And Sensitivity Analysis – Addendum, January 2022, Alan Green, Paul Cooper

Faculty of Engineering and Information Sciences - Papers: Part B

This document has been prepared as an addendum to the report ‘Hygrothermal Performance of Vapour-Permeable Wall Membranes in Cooler Australian Climates: Comparative Modelling and Sensitivity Analysis’ [1] prepared by the Sustainable Buildings Research Centre (SBRC) at the University of Wollongong under the auspices of the Australian Research Council Hub for Australian Steel Innovation. It includes results from an additional set of hygrothermal simulations, as well as further explanation of certain assumptions in the original report.

Indoor Temperatures And Energy Use In Nsw Social Housing, Daniel Daly, Theresa Harada, M P. Tibbs, Paul Cooper, Gordon R. Waitt, Federico Tartarini

Faculty of Engineering and Information Sciences - Papers: Part B

Issues of fuel poverty and thermal discomfort have been identified in social housing internationally, and have been linked with possible health risks for tenants. Statistically, many of the known factors linking poor thermal performance of a dwelling and increased health risk are over-represented in Australian social housing compared with the general housing sector. The results of a mixed-method study undertaken in social housing properties are offered to better understand the relationship between energy consumption and thermal performance in a temperate climate in New South Wales, Australia. The project design combined household energy ethnographies, home energy audits and longitudinal monitoring of …

Mlc Tracking For Lung Sabr Is Feasible, Efficient And Delivers High-Precision Target Dose And Lower Normal Tissue Dose, Jeremy Booth, Vincent Caillet, Adam Briggs, Nicholas G. Hardcastle, Georgios Angelis, Dasantha Jayamanne, Meegan Shepherd, Alexander Podreka, Kathryn Szymura, Doan Nguyen, Per Poulsen, Ricky O'Brien, Benjamin Harris, Carol Haddad, Thomas Eade, Paul Keall

Faculty of Engineering and Information Sciences - Papers: Part B

Background and purpose: The purpose of this work is to present the clinical experience from the first-in-human trial of real-time tumor targeting via MLC tracking for stereotactic ablative body radiotherapy (SABR) of lung lesions. Methods and materials: Seventeen patients with stage 1 non-small cell lung cancer (NSCLC) or lung metastases were included in a study of electromagnetic transponder–guided MLC tracking for SABR (NCT02514512). Patients had electromagnetic transponders inserted near the tumor. An MLC tracking SABR plan was generated with planning target volume (PTV) expanded 5 mm from the end-exhale gross tumor volume (GTV). A clinically approved comparator plan was generated …

Laboratory Learning Objectives Measurement: Relationships Between Student Evaluation Scores And Perceived Learning, Sasha Nikolic, Thomas Suesse, Kosta Jovanovic, Zarko Stanisavljevic

Faculty of Engineering and Information Sciences - Papers: Part B

Contribution: This article provides evidence that perceived learning has a relationship and influences the way students evaluate laboratory experiments, facilities, and demonstrators. Background: Debate continues on the capability and/or reliability of students to evaluate teaching and/or learning. Understanding such relationships can help educators decode evaluation data to develop more effective teaching experiences. Research Question: Does a relationship exist between student evaluation scores and perceived learning? Methodology: Perceived learning across the cognitive, psychomotor, and affective domains was measured using the Laboratory Learning Objectives Measurement (LLOM) tool at an Australian (344 students) and Serbian (181 students) university. A multilevel statistical analysis was …

Genetic Variation For Fusarium Crown Rot Tolerance In Durum Wheat, Gururaj Pralhad Kadkol, Jess Meza, Steven Simpfendorfer, Steve Harden, Brian R. Cullis Professor

Faculty of Engineering and Information Sciences - Papers: Part B

Tolerance to the cereal disease Fusarium crown rot (FCR) was investigated in a set of 34 durum wheat genotypes, with Suntop, (bread wheat) and EGA Bellaroi (durum) as tolerant and intolerant controls, in a series of replicated field trials over four years with inoculated (FCR-i) and non-inoculated (FCR-n) plots of the genotypes. The genotypes included con- ventional durum lines and lines derived from crossing durum with 2–49, a bread wheat geno- type with the highest level of partial resistance to FCR. A split plot trial design was chosen to optimize the efficiency for the prediction of FCR tolerance for each …

Electrospun Nanofibers For Efficient Adsorption Of Heavy Metals From Water And Wastewater, Maryam Salehi, Donya Sharafoddinzadeh, Fatemeh Mokhtari, Mitra Salehi Esfandarani, Shafieh Karami

Faculty of Engineering and Information Sciences - Papers: Part B

Heavy metals (HMs) are persistent and toxic environmental pollutants that pose critical risks toward human health and environmental safety. Their efficient elimination from water and wastewater is essential to protect public health, ensure environmental safety, and enhance sustainability. In the recent decade, nanomaterials have been developed extensively for rapid and effective removal of HMs from water and wastewater and to address the certain economical and operational challenges associated with conventional treatment practices, including chemical precipitation, ion exchange, adsorption, and membrane separation. However, the complicated and expensive manufacturing process of nanoparticles and nanotubes, their reduced adsorption capacity due to the aggregation, …

Infinitesimal Knowledges, Rodney Nillsen

Faculty of Engineering and Information Sciences - Papers: Part B

The notion of indivisibles and atoms arose in ancient Greece. The continuum—that is, the collection of points in a straight line segment, appeared to have paradoxical properties, arising from the ‘indivisibles’ that remain after a process of division has been carried out throughout the continuum. In the seventeenth century, Italian mathematicians were using new methods involving the notion of indivisibles, and the paradoxes of the continuum appeared in a new context. This cast doubt on the validity of the methods and the reliability of mathematical knowledge which had been regarded as established by the axiomatic method in geometry expounded by …

Thermal Bridging Of Horizontal Ceilings Under Pitched Roofs, Alan Green, Leela Kempton, Paul Cooper, Georgios Kokogiannakis

Faculty of Engineering and Information Sciences - Papers: Part B

A detailed investigation has been conducted into methods for determining the thermal performance of horizontal ceilings under pitched roofs. Existing literature on relevant calculation, simulation and test methods was reviewed, and an extensive computational fluid dynamics (CFD) simulation study was conducted. Results from the CFD simulations were used to assess the accuracy of standard thermal bridge calculation methods when applied to timber-framed and steel-framed ceilings under a roof space.

Event-Triggered H∞ Control For Active Seat Suspension Systems Based On Relaxed Conditions For Stability, Wenxing Li, Haiping Du, Donghong Ning, Weihua Li, Shuaishuai Sun, Jumei Wei

Faculty of Engineering and Information Sciences - Papers: Part A

© 2020 Elsevier Ltd An event-triggered H∞ controller is designed for an active seat suspension in this paper, where the continuous event-trigger scheme is applied to transfer the dynamic system states to the controller only at event-triggered time instants. Delay-dependent stability criteria in the form of linear matrix inequality (LMI) are presented to guarantee the asymptotic stability of the seat suspension system. One Lyapunov function is chosen where some matrices are introduced with relaxed conditions. Two tight inequalities are applied to prove the positive definiteness of the Lyapunov function and stability of the system, which reduces the conservatism of the …

A Hybrid Unsupervised Clustering-Based Anomaly Detection Method, Guo Pu, Lijuan Wang, Jun Shen, Fang Dong

Faculty of Engineering and Information Sciences - Papers: Part B

In recent years, machine learning-based cyber intrusion detection methods have gained increasing popularity. The number and complexity of new attacks continue to rise; therefore, effective and intelligent solutions are necessary. Unsupervised machine learning techniques are particularly appealing to intrusion detection systems since they can detect known and unknown types of attacks as well as zero-day attacks. In the current paper, we present an unsupervised anomaly detection method, which combines Sub-Space Clustering (SSC) and One Class Support Vector Machine (OCSVM) to detect attacks without any prior knowledge. The proposed approach is evaluated using the well-known NSL-KDD dataset. The experimental results demonstrate …

Towards A More Effective Bidirectional Lstm-Based Learning Model For Human-Bacterium Protein-Protein Interactions, Huaming Chen, Jun Shen, Lei Wang, Yaochu Jin

Faculty of Engineering and Information Sciences - Papers: Part B

The identification of protein-protein interaction (PPI) is one of the most important tasks to understand the biological functions and disease mechanisms. Although numerous databases of biological interactions have been published in debt to advanced high-throughput technology, the study of inter-species protein-protein interactions, especially between human and bacterium pathogens, remains an active yet challenging topic to harness computational models tackling the complex analysis and prediction tasks. In this paper, we comprehensively revisit the prediction task of human-bacterium protein-protein interactions (HB-PPI), which is a first ever endeavour to report an empirical evaluation in learning and predicting HB-PPI based on machine learning models. …

H∞ Delayed Tracking Protocol Design Of Nonlinear Singular Multi-Agent Systems Under Markovian Switching Topology, Xiangli Jiang, Guihua Xia, Zhiguang Feng, Zhengyi Jiang

Faculty of Engineering and Information Sciences - Papers: Part B

© 2020 Elsevier Inc. The consensus tracking of singular multi-agent systems (MASs) with Lipschitz-type nonlinearities and exogenous disturbances is researched in this paper. Governed by a Markov chain, the network interaction randomly switches in a directed graph set, where the directed spanning tree is not contained in each graph while exists in the union rooting at the leader node. By utilizing a collection of in-neighbors’ information that involves communication delay, the intention is to design a protocol such that the resultant consensus error system is stochastic admissible with an H∞ disturbance attenuation level. Based on algebraic graph theory, stochastic admissibility …

Utilizing Qr Codes To Verify The Visual Fidelity Of Image Datasets For Machine Learning, Yang-Wai Chow, Willy Susilo, Jianfang Wang, Richard Buckland, Joon Sang Baek, Jongkil Kim, Nan Li

Faculty of Engineering and Information Sciences - Papers: Part B

Machine learning is becoming increasingly popular in modern technology and has been adopted in various application areas. However, researchers have demonstrated that machine learning models are vulnerable to adversarial examples in their inputs, which has given rise to a field of research known as adversarial machine learning. Potential adversarial attacks include methods of poisoning datasets by perturbing input samples to mislead machine learning models into producing undesirable results. While such perturbations are often subtle and imperceptible from the perspective of a human, they can greatly affect the performance of machine learning models. This paper presents two methods of verifying the …

Hygrothermal Performance Of Vapour-Permeable Wall Membranes In Cooler Australian Climates: Comparative Modelling And Sensitivity Analysis, Alan Green, Paul Cooper

Faculty of Engineering and Information Sciences - Papers: Part B

This research project was carried out under the auspices of the Australian Research Council (ARC) Research Hub for Australian Steel Innovation (IH200100005) and follows on from earlier experimental and numerical research that explored the thermal and hygric performance of walls with ventilated cavities [1]. The new research described below extends our earlier work, with an aim to:

1. Simulate and compare the hygrothermal (heat and moisture) performance of case study walls with ‘Class 3’ reflective and ‘Class 4’ non-reflective membranes located in Australian NCC Climate Zones 6 and 7; and
2. Investigate the sensitivity of such hygrothermal simulations to modelling assumptions

Automatic Ventricular Nuclear Magnetic Resonance Image Processing With Deep Learning, Binbin Yong, Chen Wang, Jun Shen, Fucun Li, Hang Yin

Faculty of Engineering and Information Sciences - Papers: Part A

Cardiovascular diseases (CVD) seriously threaten the health of human beings, and they have caused widespread concern in recent years. At present, the diagnosis of CVD is mainly conducted by computed tomography (CT), echocardiography and nuclear magnetic resonance (NMR) technologies. NMR imaging technology is widely used in medical applications owing to its characteristics of high resolution and very low radiation. However, manual NMR image segmentation is time-consuming and error-prone, which has led to the research on automatic NMR image segmentation technologies. Researchers tend to explore the ventricular NRM image segmentation to improve the accuracy of CVD diagnosis. In this study, based …

Using Cost-Sensitive Learning And Feature Selection Algorithms To Improve The Performance Of Imbalanced Classification, Fang Feng, Kuan-Ching Li, Jun Shen, Qingguo Zhou, Xuhui Yang

Faculty of Engineering and Information Sciences - Papers: Part A

Imbalanced data problem is widely present in network intrusion detection, spam filtering, biomedical engineering, finance, science, being a challenge in many real-life data-intensive applications. Classifier bias occurs when traditional classification algorithms are used to deal with imbalanced data. As already known, the General Vector Machine (GVM) algorithm has good generalization ability, though it does not work well for the imbalanced classification. Additionally, the state-of-the-art Binary Ant Lion Optimizer (BALO) algorithm has high exploitability and fast convergence rate. Based on these facts, we have proposed in this paper a Cost-sensitive Feature selection General Vector Machine (CFGVM) algorithm based on GVM and …

Hybrid Translation And Language Model For Micro Learning Material Recommendation, Jiayin Lin

Faculty of Engineering and Information Sciences - Papers: Part A

As an emerging pedagogy, micro learning aims to make use of people’s fragmented spare time and provide personalized online learning service, for example, by pushing fragmented knowledge to specific learners. In the context of big data, the recommender system is the key factor for realizing the online personalization service, which significantly determines what information will be fmally accessed by the target learners. In the education discipline, due to the pedagogical requirements and the domain characteristics, ranking recommended learning materials is essential for maintaining the outcome of the massive learning scenario. However, many widely used recommendation strategies in other domains showed …

An In Situ Synchrotron Study Of The Localized B2↔B19' Phase Transformation In An Ni-Ti Alloy Subjected To Uniaxial Cyclic Loading-Unloading With Incremental Strains, Xiaohui Bian, Ahmed A. Saleh, Peter Lynch, Christopher Davies, Azdiar Adil Gazder, Elena V. Pereloma

Faculty of Engineering and Information Sciences - Papers: Part A

© 2020. High-resolution in situ synchrotron X-ray diffraction was applied to study a cold-drawn and solution-treated 56Ni-44Tiwt% alloy subjected to uniaxial cyclic loading-unloading with incremental strains. The micro-mechanical behaviour associated with the partial and repeated B2↔B19' phase transformation at the centre of the sample gauge length was studied with respect to the macroscopic stress-strain response. The lattice strains of the (110)B2 and different B19' grain families are affected by (i) the transformation strain, the load-bearing capacity of both phases and the strain continuity maintained at/near the B2-B19' interfaces at the centre of the gauge length, and (ii) the extent of …

Autonomous Control Strategy For Microgrid Operating Modes Smooth Transition, Yaran Li, Long Fu, Ke Meng, Zhao Dong, Kashem M. Muttaqi, Wenli Du

Faculty of Engineering and Information Sciences - Papers: Part A

© 2013 IEEE. Microgrid transition between standalone and grid-connected modes is a promising alternative to provide the grid with increasing flexibility and availability. However, transition smoothness relies heavily on control topologies and corresponding parameters, which thus remains challengeable. Existing microgrid transition strategies have two major deficiencies: 1) Inverter control mode alters subjected to microgrid operating mode, for instance, the inverter in current control will switch to voltage control when microgrid disconnects to the utility grid; 2) Controller parameters are selected based on practice and experience, where a systematic and efficient approach does not exist. Motivated by these limitations, in this …

Microstructural Evolution Of Hybrid Aluminum Matrix Composites Reinforced With Sic Nanoparticles And Graphene/Graphite Prepared By Powder Metallurgy, Jiangshan Zhang, Qing Liu, Shufeng Yang, Zhixin Chen, Qiang Liu, Zhengyi Jiang

Faculty of Engineering and Information Sciences - Papers: Part A

© 2020 Chinese Materials Research Society The dispersion of ceramic nanoparticles is of significance to the microstructure and properties of particulate reinforced metal matrix composites. In this study, two hybrid enhancers, SiC-graphite and SiC-graphene nanosheets (GNSs), were incorporated into aluminum matrix composites using powder metallurgy. The dispersion of the reinforcements and microstructural evolution of the composites were characterized by using Scanning Electron Microscopy, X-Ray Diffraction, Transmission Electron Microscopy, and Raman spectroscopy. The results show that thin GNSs accelerated the deformation of the aluminum particles, and defects were introduced into the carbonaceous phases during the ball milling process. Al4C3 needles generated …

A 3d Printed Modular Soft Gripper For Conformal Grasping, Charbel Tawk, Rahim Mutlu, Gursel Alici

Faculty of Engineering and Information Sciences - Papers: Part A

© 2020 IEEE. In this work, a 3D printed modular soft gripper with highly conformal soft fingers was developed. A soft auxetic structure with compliant ribs is 3D printed simultaneously with each soft pneumatic finger for conformal grasping. The fingers of the soft gripper were printed monolithically, without requiring support material and postprocessing, using a low-cost and open-source fused deposition modeling (FDM) 3D printer that employs a commercially available thermoplastic polyurethane (TPU). The soft fingers of the gripper were optimized using finite element modeling (FEM). The FE simulations accurately predicted the performance of the fingers in terms of deformation and …