Design integration and noise studies for jet STOL aircraft. Task 7A: Augmentor wing cruise blowing valveless system. Volume 1: System design and test integration

Exploratory design studies conducted to establish the configuration of an augmentor wing vruise blowing (valveless) system in a 150-passenger STOL airplane were reported in NASA CR-114570. Those studies have been updated to incorporate the results of static rig, flow duct, and wind tunnel tests. Minor adjustments in duct flow velocity, flap length, and blowing nozzle geometry were incorporated to provide airplane characteristics that minimize takeoff gross weight and achieve sideline noise objectives for an advanced commercial STOL airplane

Labour supply and skills demands in fashion retailing

If, as Adam Smith once famously suggested, Britain was a nation of shopkeepers then it is now a nation of shopworkers. Retail is now a significant part of the UK economy, accounting for £256 billion in sales and one-third of all consumer spending (Skillsmart, 2007). It is the largest private sector employer in the UK, employing 3m workers, or 1 in 10 of the working population. For future job creation in the UK economy retail is also similarly prominent and the sector is expected to create a further 250,000 jobs to 2014 (Skillsmart, 2007). The centrality of retail to economic success and job creation is apparent in other advanced economies. For example, within the US, retail sales is the occupation with the largest projected job growth in the period 2004-2014 (Gatta et al., 2009) and in Australia retail accounts for 1 in 6 workers (Buchanan et al., 2003). Within the UK these workers are employed in approximately 290,000 businesses, encompassing large and small organizations and also a number of sub-sectors. This variance suggests that retail should not be regarded as homogenous in its labour demands. Hart et al. (2007) note how skill requirements and the types of workers employed may differ across the sector. This chapter further opens up this point, providing an analysis of the labour supply and skills demands for the sub-sectors of clothing, footwear and leather goods, which are described by Skillsmart (2007: 48) as being 'significant categories in UK retailing'

Real-time monitoring as a supplementary security component of vigilantism in modern network environments

© 2020, The Author(s). The phenomenon of network vigilantism is autonomously attributed to how anomalies and obscure activities from adversaries can be tracked in real-time. Needless to say, in today’s dynamic, virtualized, and complex network environments, it has become undeniably necessary for network administrators, analysts as well as engineers to practice network vigilantism, on traffic as well as other network events in real-time. The reason is to understand the exact security posture of an organization’s network environment at any given time. This is driven by the fact that modern network environments do, not only present new opportunities to organizations but also a different set of new and complex cybersecurity challenges that need to be resolved daily. The growing size, scope, complexity, and volume of networked devices in our modern network environments also makes it hard even for the most experienced network administrators to independently provide the breadth and depth of knowledge needed to oversee or diagnose complex network problems. Besides, with the growing number of Cyber Security Threats (CSTs) in the world today, many organisations have been forced to change the way they plan, develop and implement cybersecurity strategies as a way to reinforce their ability to respond to cybersecurity incidents. This paper, therefore, examines the relevance of Real-Time Monitoring (RTM) as a supplementary security component of vigilantism in modern network environments, more especially for proper planning, preparedness, and mitigation in case of a cybersecurity incident. Additionally, this paper also investigates some of the key issues and challenges surrounding the implementation of RTM for security vigilantism in our modern network environments

The Politics of Service Delivery Reform

This article identifies the leaders, the supporters and the resisters of public service reform. It adopts a principal–agent framework, comparing reality with an ‘ideal’ situation in which citizens are the principals over political policy-makers as their agents, and policy-makers are the principals over public service officials as their agents. Reform in most developing countries is complicated by an additional set of external actors — international financial institutions and donors. In practice, international agencies and core government officials usually act as the ‘principals’ in the determination of reforms. The analysis identifies the interests involved in reform, indicating how the balance between them is affected by institutional and sectoral factors. Organizational reforms, particularly in the social sectors, present greater difficulties than first generation economic policy reforms

Giving Miss Marple a makeover : graduate recruitment, systems failure and the Scottish voluntary sector

The voluntary sector in Scotland, as across the globe, is becoming increasingly business like. Resultantly, there is an increasing demand for graduates to work in business and support functions. In Scotland, however, despite an oversupply of graduates in the labor market, the voluntary sector reports skills shortages for graduate-level positions; a leadership deficit was also reported in countries such as the United States. Through exploratory, mainly qualitative, case study and stakeholder research, this article proposes that one reason for this mismatch between the supply of and demand for graduates is a systems failure within the sector. Many graduates and university students remain unaware of potentially suitable paid job opportunities, in part because of the sector's voluntary label. To rectify this systems failure, thought needs to be given to the sector's nomenclature and the manner in which voluntary sector organizations attract graduate recruits, for example, through levering value congruence in potential recruits

Ontology‐driven perspective of CFRaaS

A Cloud Forensic Readiness as a Service (CFRaaS) model allows an environment to preemptively accumulate relevant potential digital evidence (PDE) which may be needed during a post‐event response process. The benefit of applying a CFRaaS model in a cloud environment, is that, it is designed to prevent the modification/tampering of the cloud architectures or the infrastructure during the reactive process, which if it could, may end up having far‐reaching implications. The authors of this article present the reactive process as a very costly exercise when the infrastructure must be reprogrammed every time the process is conducted. This may hamper successful investigation from the forensic experts and law enforcement agencies perspectives. The CFRaaS model, in its current state, has not been presented in a way that can help to classify or visualize the different types of potential evidence in all the cloud deployable models, and this may limit the expectations of what or how the required PDE may be collected. To address this problem, the article presents the CFRaaS from a holistic ontology‐driven perspective, which allows the forensic experts to be able to apply the CFRaaS based on its simplicity of the concepts, relationship or semantics between different form of potential evidence, as well as how the security of a digital environment being investigated could be upheld. The CFRaaS in this context follows a fundamental ontology engineering approach that is based on the classical Resource Description Framework. The proposed ontology‐driven approach to CFRaaS is, therefore, a knowledge‐base that uses layer‐dependencies, which could be an essential toolkit for digital forensic examiners and other stakeholders in cloud‐security. The implementation of this approach could further provide a platform to develop other knowledge base components for cloud forensics and security

Acoustic characterisation of a small high-speed centrifugal compressor with casing treatment: an experimental study

[EN] With the advancements in manufacturing, materials and computational methods, turbomachinery designs have become more efficient providing higher specific power and reliability with lower weight and cost. The rotational speed of turbomachines has increased while the overall machine size has decreased for a similar power output leading to the pervasive presence of small, high-speed turbomachines, specifically centrifugal compressors in helicopters, unmanned aerial vehicles (UAVs), auxiliary power units (APUs), turbochargers and micro gas turbines. In addition to superior aerodynamic performance over a wide range, increased operating speeds have made the acoustic emissions of small centrifugal compressors a critical aspect of design. Therefore, this work presents an experimental campaign to characterise the acoustic behaviour of a compressor with an intent to quantify the dominant features of the flow-induced noise for design and near surge operating conditions. Furthermore, the campaign is extended to establish the impact of the ported shroud casing treatment and operating speed on the acoustic emission of the compressor. The in-duct noise measurement method is used in this work to quantify the noise generated in the compressor by measuring pressure fluctuations near the inducer and diffuser while the propagation of the generated noise to the ducts is computed from an array of piezoelectric sensors. Spectra at the design operating point are dominated by tonal noise while broadband noise content is the dominant feature of spectra for near surge operation. Although the ported shroud cavity does not significantly alter the overall noise levels of the compressor operating at design condition, it does seem to propagate tonal noise. For near surge operation, the casing treatment positively impacts the acoustic emission with a reduction of approximately 10 dB in the range up to the blade pass frequency. Furthermore, various broadband features are also observed to be alleviated by the casing treatment. (C) 2019 Elsevier Masson SAS. All rightsThe project was sponsored and supported by BorgWarner Turbo Systems and the Regional Growth Fund (RGF Grant Award 01.09.07.01/1789C). The authors would like to thank BorgWarner Turbo Systems for permission to publish the results presented in this paper.Sharma, S.; Broatch, A.; Garcia Tiscar, J.; Allport, JM.; Nickson, AK. (2019). Acoustic characterisation of a small high-speed centrifugal compressor with casing treatment: an experimental study. Aerospace Science and Technology. 95:1-15. https://doi.org/10.1016/j.ast.2019.1055181159

Acoustic and pressure characteristics of a ported shroud turbocompressor operating at near surge conditions

[EN] The operation of compressor at lower mass flow rates is limited by surge which is marked by large fluctuations in operational variables and accompanied by significant increase in noise. Ported shroud casing treatment is a widely used method to control the flow near unstable conditions in order to obtain a stable operation and enhance deep surge margin. The research on the acoustic effects of the ported shroud design is limited. Therefore, this paper numerically characterises the acoustic features of a turbocharger compressor with ported shroud design operating at marginal or soft surge conditions and investigates the correlation between acoustic characteristics and the spatial flow structures. The acoustic and the flow field features are analysed using spectral signatures obtained from an experimentally validated numerical model using both performance and acoustic measurements. Propagation of the frequency content through the ducts has been estimated with the aid of the beamforming and method of characteristics to enhance the content coming from the compressor. Expected acoustic phenomena such as rotating order tones and blade passing peaks are correctly identified in the modelled spectrum with the limitation to capture the specific broadband features. Hence, the numerical model can be used to further the research encompassing the impact these flow enhancement solutions have on the noise emission of the turbocharger. Inspection of the flow field shows radially exiting fluid at the ported shroud slot leading to the formation of the high-speed jets exiting the ported shroud cavity. Circumferential propagation of the stall cells is also identified in the impeller. Further inspection of the pressure field through modal decomposition implies the localisation of the energetic noise sources in the impeller downstream components. The influence of the ported shroud cavity on the acoustic characteristic of the compressor is not significant and is limited to the propagation of the tonal noise in the direction of impeller upstream. (C) 2019 Elsevier Ltd. All rights reserved.The project is sponsored and supported by BorgWarner Turbo Systems and the Regional Growth Fund (RGF Grant Award 01.09.07.01/1789C). The authors would like to thank BorgWarner Turbo Systems for permission to publish the results presented in this paper. The support of the HPC group at the University of Huddersfield is gratefully acknowledged.Sharma, S.; Broatch, A.; Garcia Tiscar, J.; Nickson, AK.; Allport, JM. (2019). Acoustic and pressure characteristics of a ported shroud turbocompressor operating at near surge conditions. Applied Acoustics. 148:434-447. https://doi.org/10.1016/j.apacoust.2019.01.005S43444714