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Reynolds-averaged Navier–Stokes (RANS) models often perform poorly in shock/turbulence interaction regions, resulting in excessive wall heat load and incorrect representation of the separation length in shockwave/turbulent boundary layer interactions. The authors suggest that this can be traced back to inadequate numerical treatment of the inviscid fluxes. The purpose of this study is an extension to the well-known Harten, Lax, van Leer, Einfeldt (HLLE) Riemann solver to overcome this issue.

It explicitly takes into account the broadening of waves due to the averaging procedure, which adds numerical dissipation and reduces excessive turbulence production across shocks. The scheme is derived based on the HLLE equations, and it is tested against three numerical experiments.

Sod’s shock tube case shows that the scheme succeeds in reducing turbulence amplification across shocks. A shock-free turbulent flat plate boundary layer indicates that smooth flow at moderate turbulence intensity is largely unaffected by the scheme. A shock/turbulent boundary layer interaction case with higher turbulence intensity shows that the added numerical dissipation can, however, impair the wall heat flux distribution.

The proposed scheme is motivated by implicit large eddy simulations that use numerical dissipation as subgrid-scale model. Introducing physical aspects of turbulence into the numerical treatment for RANS simulations is a novel approach.

The purpose of this paper is to review recent progress in electronic nose technologies, focusing on hybrid systems combining biological elements with physical transducers.

Electronic nose technologies are moving rapidly towards hybrid bioelectronic systems, where biological odour-recognition elements from the olfactory pathways of vertebrates and insects are being utilised to construct new “bionic noses” that can be used in industrial applications.

With the increased understanding of how chemical senses and the brain function in biology, an emerging field of “neuromorphic olfaction” has arisen.

Important components are olfactory receptor proteins and soluble proteins found at the periphery of olfaction called odorant-binding proteins. The idea is that these proteins can be incorporated into transducers and function as biorecognition elements for volatile compounds of interest.

Major drivers are the security, environmental and medical applications, and the internet of things will be a major factor in implementing low-cost chemical sensing in networked applications for the future.

Widespread take up of new technologies that are cheap will minimise the impact of environmental pollution, increase food safety and may potentially help in non-invasive screening for medical ailments.

This review brings together diverse threads of research leading to a common theme that will inform a non-expert of recent developments in the field.

This work has been motivated by the authors' long‐term research on odor‐sensing systems using acoustic wave‐based sensors and pattern recognition techniques. The sensors should be fabricated in such a way that they mimic performance of the olfactory receptors. In these terms, the purpose of this paper is to test a simple method for fabrication of quartz crystal microbalance (QCM) sensors by using nanocomposites and amphiphilic gas chromatography (GC) materials. The obtained sensors were intended to be highly sensitive to odorants at low concentrations and in high‐humidity conditions, as well as contributing to discrimination among odorant samples.

The proposed fabrication process consists of four stages: formation of all‐lipopolymeric layer on surface of the QCM sensor; preparation of lipopolymeric nanocomposites by means of chemisorption of lipopolymers onto nano‐Au; precipitation of the nanocomposites onto the lipopolymer‐coated QCM surface; and physisorption of amphiphilic GC materials onto the lipopolymer‐nanocomposite matrix. The fabricated sensors have been evaluated in the experiments of exposure to vapors of odorants at various concentrations and humidity levels.

The authors found that sensitivity of the sensors fabricated using the proposed method was much superior to that recorded for the sensors with all‐lipopolymeric and all‐amphiphilic films. The novel sensors' performance showed robustness against humidity and capability to discriminate among odorant samples at relatively low‐concentration levels.

The sensors fabricated using the proposed method can be useful in recognition of the odorant samples at ppb‐level under high humidity. Their performance has not been deteriorated even under high humidity.

The paper presents application of a relatively simple chemi‐/physisorption processes to form an odor‐interactive coating, with high sensitivity and robustness against humidity. To the best of the authors' knowledge, the method proposed here has not been presented by other groups.

Olfaction plays a very important role in daily life. The olfactory system has the ability to recognize, discriminate and identify thousands of odorant compounds with extremely high sensitivity and specificity. The research on olfactory system has very important values in exploring the mechanisms of information processing in the other sensory nervous systems and brain. Recently, with the development of molecular biological and microelectronics technology research, the study of olfactory cell-based sensors has made great progress. The purpose of this paper is to provide details of recent developments in olfactory cell-based sensors.

Following an introduction, this paper first discusses some olfactory cell-based biosensors, which focus on the light-addressable potentiometric sensors and the microelectrode arrays. Second, surface modification, microfabrication and microfluidic technology which can improve the efficiency of cell immobilization will be summarized. The research trends of olfactory cell-based sensor in future will be proposed.

This paper shows that the biosensors’ performance is expected to be greatly improved due to the fast development of nanotechnology, optical technology and microelectronics. More and more emerging intelligent olfactory sensors will have a promising prospect in many application fields, including food quality and safety assessment, environmental monitor and human diseases detection.

This paper provides a detailed and timely review of the rapidly growing research in the olfactory cell-based sensors.

To examine whether indigenous critiques of globalization and critical theories of modernity are compatible, and how they can complement each other so as to engender more realistic theories of modern society as inherently constructive and destructive, along with practical strategies to strengthen modernity as a culturally transformative project, as opposed to the formal modernization processes that rely on and reinforce modern societies as structures of social inequality.

Comparison and assessment of the foundations, orientations, and implications of indigenous critiques of globalization and the Frankfurt School’s critical theory of modern society, for furthering our understanding of challenges facing human civilization in the twenty-first century, and for opportunities to promote social justice.

Modern societies maintain order by compelling individuals to subscribe to propositions about their own and their society’s purportedly “superior” nature, especially when compared to indigenous cultures, to override observations about the de facto logic of modern societies that are in conflict with their purported logic.

Social theorists need to make consistent efforts to critically reflect on how their own society, in terms of socio-historical circumstances as well as various types of implied biases, translates into research agendas and propositions that are highly problematic when applied to those who belong to or come from different socio-historical contexts.

An effort to engender a process of reciprocal engagement between one of the early traditions of critiquing modern societies and a more recent development originating in populations and parts of the world that historically have been the subject of both constructive and destructive modernization processes.

The burden social theorists must be willing to accept, respond to, and act upon pertains to the difficulties that predictably accompany all efforts to convey to nontheorists the unwelcome fact of heteronomy – that as actors, we are not as autonomous as we were told and prefer to assume – and to spell out what heteronomy in the form in which it has been shaping the developmental trajectory of modern societies means for professional theorists. I introduce the concept of “vitacide,” designed to capture that termination of life is a potential vanishing point of the heteronomous processes that have been shaping modern societies continuing to accelerate and intensify in ways that prefigure our future, but not on our human or social terms. Heteronomy pointing toward vitacide should compel us as social theorists to consider critically both the constructive and destructive trajectory that social change appears to have been following for more than two centuries, irrespective of whether the resulting prospect is to our liking or not. In this context, the classical critical theorists of the early Frankfurt School, especially Max Horkheimer and Theodor W. Adorno, pursued what turned out to be an evolving interest in rackets, the authoritarian personality, and the administered society – concepts that served as foils for delineating the kind of theoretical stance that is becoming more and more important as we are moving into an increasingly uncertain future.

On the face of it, there may not seem much in common with a World Bank project to increase the productivity of Nicaraguan farmers, and British financial institutions’ need to bring profitable new products and services on stream quickly. Or with a US office‐product company’s determination to significantly increase revenues, or a Danish underwater acoustics company’s aim to reduce product development times from three years to three months.

Purpose – Although the US has lagged behind international developments in health technology assessment (HTA), renewed interest in HTA in the US has been fueled by the appropriation of $1.1 billion comparative effectiveness research (CER) in 2009 and the debate over health care reform.

Approach – To inform CER practices in the US, we present case studies of HTA from England/Wales and Germany: contrasting methods; relevance to the US; and impact on innovation.

Findings – The National Institute of Health and Clinical Excellence (NICE) was established in 1999 to inform trusts within the National Health Service of England and Wales. It uses cost-effectiveness analysis to guide the allocation resource across preventative and curative interventions. In Germany, the Institut für Qualität und Wirtschaftlichkeit im Gesundheitswesen (IQWiG) was established in 2004 to inform reimbursement and pricing policies for the statutory sickness funds set by the Gemeinsamer Bundesausschuss (G-BA). IQWiG evaluates competing technologies within specific therapeutic areas, placing more weight on clinical evidence and the relative efficiency of competing therapies.

Practical implications – Although having deep political and cultural antecedents, differences between NICE and IQWiG can be explained by perspective: the former guiding resource allocation across an entire system (macro-evaluation), the latter focusing on efficiency within the bounds of a particular therapeutic area (micro-evaluation). Given the decentralized nature of the US health care system, and the relative powers of different medical specialties, the IQWiG model presents a more suitable case study to guided CER efforts in the US.