Helicopter main-rotor noise: Determination of source contributions using scaled model data

Acoustic data from a test of a 40 percent model MBB BO-105 helicopter main rotor are scaled to equivalent full-scale flyover cases. The test was conducted in the anechoic open test section of the German-Dutch Windtunnel (DNW). The measured data are in the form of acoustic pressure time histories and spectra from two out-of-flow microphones underneath and foward of the model. These are scaled to correspond to measurements made at locations 150 m below the flight path of a full-scale rotor. For the scaled data, a detailed analysis is given for the identification in the data of the noise contributions from different rotor noise sources. Key results include a component breakdown of the noise contributions, in terms of noise criteria calculations of a weighted sound pressure level (dBA) and perceived noise level (PNL), as functions of rotor advance ratio and descent angle. It is shown for the scaled rotor that, during descent, impulsive blade-vortex interaction (BVI) noise is the dominant contributor to the noise. In level flight and mild climb, broadband blade-turbulent wake interaction (BWI) noise is dominant due to the absence of BVI activity. At high climb angles, BWI is reduced and self-noise from blade boundary-layer turbulence becomes the most prominent

Divergence of Safety and Security

© 2020, The Author(s). Safety and security have similar goals, to provide social wellness through risk control. Such similarity has led to views of professional convergence; however, the professions of safety and security are distinct. Distinction arises from variances in concept definition, risk drivers, body of knowledge, and professional practice. This chapter explored the professional synergies and tensions between safety and security professionals, using task-related bodies of knowledge. Findings suggest that safety and security only have commonalities at the overarching abstract level. Common knowledge does exist with categories of risk management and control; however, differences are explicit. In safety, risk management focuses on hazards management, whereas security focuses on threat mitigation. Safety theories consider health impacts and accidents, whereas security crime and crime prevention. Therefore, safety and security are diverging as distinct professions

An Intensive Archeological Survey and Testing of the Proposed Lower Dorchester County Wastewater Facilities Project Area Near Summerville, South Carolina

https://scholarcommons.sc.edu/archanth_books/1174/thumbnail.jp

Toward biodefence: A framework for the mitigation of malicious threats to livestock production enterprises in Australia

Biosecurity underpins the Australian agricultural sector, estimated to be worth $51 billion in exports and trade,$50 billion in tourism, $5.7 trillion in environmental assets, and more than 1.6 million jobs. Given the value to the Australian economy and the potential consequences of a deliberately introduced biological agent, measures to prevent malicious biosecurity threats are critical for national security. Using the framework of Situational Crime Prevention (SCP), the study examined recommended biosecurity practices for cattle production enterprises in Australia and explored the extent to which the Australian biosecurity framework is underpinned by preventative security. The study found the existing biosecurity framework has limited theoretical security underpinning and is constituted by practices primarily aimed at preventing naturally occurring and accidental threats, rather than an active preventative security approach at the farming level to mitigate threats of a malicious or deliberate nature. These findings identify a deficit in Australia’s national security approach to biosecurity in cattle production enterprises, establishing a need for biosecurity recommendations at an industry and primary production level to embed security theory and principles to account for malicious actors in alignment with international biodefence strategy. Subsequently, the study demonstrated how security theory can be applied to biosecurity and the agricultural sector more broadly and developed an SCP framework toward biodefence of agriculture, converging biosecurity and security as a bilateral approach to mitigating naturally occurring, accidental, and deliberate biosecurity threats

The efficacy of aligning lessons learnt from significant bushfire incidents to the organisational stratum

Australia\u27s bushfire seasons are expected to become longer and more severe due to the effects of climate change and an increasing population living in rural-urban fringes. Social and economic vulnerability to extreme natural hazards means that Australia’s emergency services sector plays a significant role in community safety and wellbeing. Therefore, it is important that the sector continually improves. Australia has a long history of conducting external reviews into significant bushfires. While these reviews receive good support and seek to identify relevant lessons, barriers remain that prevent these lessons from being effectively learnt. It is possible that some of these barriers exist because the stratum of work impedes the capture, codifying and adjustments to systems. This research investigated the premise that lessons learnt in the Australian emergency services sector occurs on a stratum, with different types of lessons learnt at different levels of work. Four significant independent bushfire reviews were analysed to evaluate whether specific lessons could be aligned to the stratum of work. Findings were that not all lessons apply to all levels of organisations. This supports the premise that lessons are learnt on a vertical organisational stratum; for example, some lessons were operational, others were tactical and some were strategic. It was determined that a lack of understanding of the barriers within an organisations stratum could impede the effectiveness of lessons being learnt

Decision-making in balancing fire safety hazards against security threats within the built environment

The built environment faces challenges from fire hazards and threats by malicious actors. Risks presented from these hazards and threats are managed through the practices of fire safety and physical security. Whilst distinct disciplines, both impact the built environment systems, resulting in potential conflict. To manage this conflict, a complex process is required. Through the framework of Governmentality, using a mixed methods approach, the study explored the process which fire safety engineers and security practitioners undertake to manage this conflict. The study produced a conceptual model that explains how practitioners operate and manage risk associated with fire safety hazards and security threats. The model indicates that the process for resolving conflicts is a dichotomy between physical security and fire safety, with fire safety being the most dominate and influential. Nevertheless, both fire safety and physical security are subservient to building regulations in this process; however unlike security, fire safety is codified through building regulations. Risk assessment and the design process are core processes, but only used in decision-making when there is conflict between the fire safety and physical security. Findings demonstrated that context remains static for greater threats, whereas context is dynamic for fire safety

Epidemic predictions in an imperfect world : modelling disease spread with partial data

‘Big-data’ epidemic models are being increasingly used to influence government policy to help with control and eradication of infectious diseases. In the case of livestock, detailed movement records have been used to parametrize realistic transmission models. While livestock movement data are readily available in the UK and other countries in the EU, in many countries around the world, such detailed data are not available. By using a comprehensive database of the UK cattle trade network, we implement various sampling strategies to determine the quantity of network data required to give accurate epidemiological predictions. It is found that by targeting nodes with the highest number of movements, accurate predictions on the size and spatial spread of epidemics can be made. This work has implications for countries such as the USA, where access to data is limited, and developing countries that may lack the resources to collect a full dataset on livestock movements

Topographic determinants of foot and mouth disease transmission in the UK 2001 epidemic

Background A key challenge for modelling infectious disease dynamics is to understand the spatial spread of infection in real landscapes. This ideally requires a parallel record of spatial epidemic spread and a detailed map of susceptible host density along with relevant transport links and geographical features. Results Here we analyse the most detailed such data to date arising from the UK 2001 foot and mouth epidemic. We show that Euclidean distance between infectious and susceptible premises is a better predictor of transmission risk than shortest and quickest routes via road, except where major geographical features intervene. Conclusion Thus, a simple spatial transmission kernel based on Euclidean distance suffices in most regions, probably reflecting the multiplicity of transmission routes during the epidemic

Corporate security career progression: A comparative study of four Australian organisations

© 2019, Springer Nature Limited. The study investigated the Corporate Security stratum of work within large Australian organisations, seeking to extract professional seating, roles, associated task complexity, career opportunity and progression ceilings as articulated through the socio-organisational literature. Two phases were applied: Phase One used online surveys distributed to participants (N = 53) across four Australian organisations, Phase Two employed semi-structured interviews and focus groups (N = 14). Findings reinforced the established literature articulation of corporate security’s roles; however, they contested the current articulation of corporate security’s executive level seating within large organisations. Instead, the study identified a Corporate Security seating with a restricted sphere of risk-based influence, along with a maximum career level at general manager. The study demonstrates an occupational corporate security ceiling, debunking the security executive belief. Corporate security was located within the technostructure group as a specialist, limiting opportunity for executive level roles or strategic influence