Multi-objective design of multi-material truss lattices utilizing graph neural networks.

The rapid advancements in additive manufacturing (AM) across different scales and material classes have enabled the creation of architected materials with highly tailored properties. Beyond geometric flexibility, multi-material AM further expands design possibilities by combining materials with distinct characteristics. While machine learning has recently shown great potential for the fast inverse design of lattice structures, its application has largely been limited to single-material systems.

Scheduling optimisation of alcohol test sites.

Drink driving is an infamous factor in road crashes and fatalities. Alcohol testing is a major countermeasure, and random breath tests (RBTs) deter tested drivers and passersby (observers who are not tested). We propose a genetic algorithm (GA)-based RBT scheduling optimisation method to achieve maximal deterrence of drink driving.

A meshless computational framework for studying cold spray additive manufacturing including large numbers of powder particles with diverse characteristics.

Cold spray (CS) has emerged as an appealing additive manufacturing (AM) technique for producing or repairing individual components or entire structures. Compared to fusion-based AM technologies, cold spray additive manufacturing (CSAM) offers distinct advantages in the fabrication of components, while avoiding some melting/solidification-related issues such as phase transformation and oxidation. It involves intricate processes that pose significant challenges for numerical modeling, particularly when simulating the entire process at a large scale.

Laser Ablation Study of Cutting Ceramics with Consideration of the Beam Inclination Angle.

Silicon alumina nitride (SiAlON) and alumina toughened zirconia (ATZ) ceramics are applied for ceramic cutting tools to machine, e.g., cast iron, nickel base alloys and other difficult-to-machine materials.

Digitisation of metal AM for part microstructure and property control.

Metal additive manufacturing, which uses a layer-by-layer approach to fabricate parts, has many potential advantages over conventional techniques, including the ability to produced complex geometries, fast new design part production, personalised production, have lower cost and produce less material waste. While these advantages make AM an attractive option for industry, determining process parameters which result in specific properties, such as the level of porosity and tensile strength, can be a long and costly endeavour. In this review, the state-of-the-art in the control of part properties in AM is examined, including the effect of microstructure on part properties.

Microstructures and Mechanical Properties of Hybrid, Additively Manufactured TiAlV after Thermomechanical Processing.

In the present study, we propose a hybrid manufacturing route to produce high-quality TiAlV parts, combining additive powder laser directed energy deposition (L-DED) for manufacturing of preforms, with subsequent hot forging as a thermomechanical processing (TMP) step. After L-DED, the material was hot formed at two different temperatures (930 °C and 1070 °C) and subsequently heat-treated for stress relief annealing. Tensile tests were performed on small sub-samples, taking into account different sample orientations with respect to the L-DED build direction and resulting in very good tensile strengths and ductility properties, similar or superior to the forged material.

Integrated Forming and Surface Engineering of Disc Springs by Inducing Residual Stresses by Incremental Sheet Forming.

Disc springs are conical annular discs, which are characterized by a high spring force with a small spring travel and good space utilization. In operation, they must meet high demands on the stability of the spring characteristic and the fatigue strength. Under loading, tensile stresses occur which limit the possible applications of disc springs.

Comparison of Microstructure and Mechanical Properties of Scalmalloy Produced by Selective Laser Melting and Laser Metal Deposition.

The second-generation aluminum-magnesium-scandium (Al-Mg-Sc) alloy, which is often referred to as Scalmalloy, has been developed as a high-strength aluminum alloy for selective laser melting (SLM). The high-cooling rates of melt pools during SLM establishes the thermodynamic conditions for a fine-grained crack-free aluminum structure saturated with fine precipitates of the ceramic phase Al₃-Sc. The precipitation allows tensile and fatigue strength of Scalmalloy to exceed those of AlSi10Mg by ~70%.

Development of a Model for Dynamic Recrystallization Consistent with the Second Derivative Criterion.

Dynamic recrystallization (DRX) processes are widely used in industrial hot working operations, not only to keep the forming forces low but also to control the microstructure and final properties of the workpiece. According to the second derivative criterion (SDC) by Poliak and Jonas, the onset of DRX can be detected from an inflection point in the strain-hardening rate as a function of flow stress. Various models are available that can predict the evolution of flow stress from incipient plastic flow up to steady-state deformation in the presence of DRX.

Personal injury recovery cost of pedestrian-vehicle collisions in New South Wales, Australia.

Background: There is a need for routine estimates of injury recovery costs from pedestrian collisions using hospital separation records for economic evaluations.

Objective: To estimate the cost of injury recovery following pedestrian-vehicle collisions using the personal injury recover cost (PIRC) equation using key demographic and injury characteristics.

Method: An estimation of the costs of on-road pedestrian-vehicle collisions involving individuals who were injured and hospitalized in New South Wales (NSW), Australia, from 2002 to 2011 using the PIRC equation.

Estimating the human recovery costs of seriously injured road crash casualties.

Road crashes result in substantial trauma and costs to societies around the world. Robust costing methods are an important tool to estimate costs associated with road trauma, and are key inputs into policy development and cost-benefit analysis for road safety programmes and infrastructure projects. With an expanding focus on seriously injured road crash casualties, in addition to the long standing focus on fatalities, methods for costing seriously injured casualties are becoming increasingly important.

Injury risk for matched front and rear seat car passengers by injury severity and crash type: An exploratory study.

Background: The risk of serious injury or death has been found to be reduced for some front compared to rear seat car passengers in newer vehicles. However, differences in injury severity between car occupants by seating position has not been examined. This study examines the injury severity risk for rear compared to front seat car passengers.

Comparison of novice and full-licenced driver common crash types in New South Wales, Australia, 2001-2011.

Objective: To examine the circumstances of passenger vehicle crashes for novice licenced drivers aged 17-25 years and to compare the crash circumstances of the most common crash types for novices to a sample of full-licence drivers aged 40-49 years.

Method: A retrospective analysis was conducted of passenger vehicle crashes involving novice and full-licenced drivers during 1 January 2001 to 31 December 2011 in New South Wales (NSW), Australia.

Results: There were 4113 injurious crashes of novice drivers.

Risk factors associated with the severity of injury outcome for paediatric road trauma.

Road trauma is one of the most common causes of injury for children. Yet risk factors associated with different levels of injury severity for childhood road trauma have not been examined in-depth. This study identifies crash and injury risk factors associated with the severity of non-fatal injury outcome for paediatric road trauma.

Examination of narratives from emergency department presentations to identify road trauma, crash and injury risk factors for different age groups.

Background: Road trauma represents a high proportion of injury-related emergency department presentations. Narrative text recorded in the emergency department could provide useful information to monitor road trauma and to identify crash and injury risk factors by age group.

Objective: To examine the Public Health Real-time Emergency Department Surveillance System (PHREDSS) to identify road users (i.

The role of evidence, standards and education in rock fishing safety in New South Wales, Australia.

Objective: To examine rock fishing-related fatalities and hospitalisations, identify initiatives aimed at improving safety and survey key rock fishing stakeholders about the strengths and limitations of each initiative.

Method: This research obtained information from mortality and hospitalisation statistics, the published literature and key stakeholders for opinions on the strengths, limitations and improvements for rock fishing safety initiatives.

Results: Injury patterns involving rock fishers have largely remained unchanged over time.

Safe system approach to reducing serious injury risk in motorcyclist collisions with fixed hazards.

Collisions with fixed objects in the roadway environment account for a substantial proportion of motorcyclist fatalities. Many studies have identified individual roadway environment and/or motorcyclist characteristics that are associated with the severity of the injury outcome, including the presence of roadside barriers, helmet use, alcohol use and speeding. However, no studies have reported the cumulative benefit of such characteristics on motorcycling safety.

Data linkage for injury surveillance and research in Australia: perils, pitfalls and potential.

Objective: To outline some of the key issues for injury-related data linkage studies in Australia and describe potential applications of data linkage for injury surveillance and research.

Methods: Narrative review of data linkage capacity and injury-related data collection quality in Australia.

Results: The establishment of national and state-based data linkage centres in Australia has been a great leap forward for data linkage capacity for injury research.

Head and spine injuries sustained by motorcyclists in head-leading collisions with fixed roadside objects.

Objective: Motorcyclist collisions with fixed objects account for a substantial proportion of fatalities in many countries. Biomechanically valid crash test protocols are required to assess the injury potential of different fixed objects to motorcyclists and/or to develop safety devices that ameliorate this injury risk. The aim of the present article is to provide field-observed injury data pertaining to motorcyclist head-leading collisions with fixed objects to assist in the development of crash test protocols.

The rising burden of serious thoracic trauma sustained by motorcyclists in road traffic crashes.

In many countries increased on-road motorcycling participation has contributed to increased motorcyclist morbidity and mortality over recent decades. Improved helmet technologies and increased helmet wearing rates have contributed to reductions in serious head injuries, to the point where in many regions thoracic injury is now the most frequently occurring serious injury. However, few advances have been made in reducing the severity of motorcyclist thoracic injury.

The protective effect of roadside barriers for motorcyclists.

Objective: Roadside barriers are often deployed between road users and fixed hazards to protect users from injury. However, the United States and Australian Roadside Design Guides do not consider motorcyclists in the risk-based decision process for the deployment of a barrier, because the severity indices for barriers and fixed hazards were developed for passenger vehicles. The aim of the present article is to quantify the protective effect of barriers with regards to motorcyclist injury and to thereby inform the Roadside Design Guides as to the relative severity of roadside hazards and infrastructure for motorcyclists.

Can SNOMED CT as implemented in New South Wales, Australia be used for road trauma injury surveillance in emergency departments?

The introduction of Systematized Nomenclature of Medicine - Clinical Terms (SNOMED CT) for diagnosis coding in emergency departments (EDs) in New South Wales (NSW) has implications for injury surveillance abilities. This study aimed to assess the consequences of its introduction, as implemented as part of the ED information system in NSW, for identifying road trauma-related injuries in EDs. It involved a retrospective analysis of road trauma-related injuries identified in linked police, ED and mortality records during March 2007 to December 2009.

Head injuries to restrained occupants in single-vehicle pure rollover crashes.

Objective: Studies performed previously of seat-belted occupants in real-world passenger vehicle rollover-only crashes have identified the head as one of the body regions most often seriously injured. However, there have been few studies investigating how these head injuries occur in any detail. This study aims to investigate the characteristics and patterns of head injury to seat-belted occupants in real-world rollover-only crashes and to identify possible biomechanical mechanisms responsible for head injury to aid in the development of a dynamic rollover test protocol.

The effectiveness of helmets in bicycle collisions with motor vehicles: a case-control study.

There has been an ongoing debate in Australia and internationally regarding the effectiveness of bicycle helmets in preventing head injury. This study aims to examine the effectiveness of bicycle helmets in preventing head injury amongst cyclists in crashes involving motor vehicles, and to assess the impact of 'risky cycling behaviour' among helmeted and unhelmeted cyclists. This analysis involved a retrospective, case-control study using linked police-reported road crash, hospital admission and mortality data in New South Wales (NSW), Australia during 2001-2009.

Thoracic injuries to contained and restrained occupants in single-vehicle pure rollover crashes.

Around one in three contained and restrained seriously injured occupants in single-vehicle pure rollover crashes receive a serious injury to the thorax. With dynamic rollover test protocols currently under development, there is a need to understand the nature and cause of serious thoracic injuries incurred in rollover events. This will allow decisions to be made with regards to adoption of a suitable crash test dummy and appropriate thoracic injury criteria in such protocols.