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The purpose of this paper is to understand the effect of airflow dynamics on vortices for different flow rates using the human nose three-dimensional model.

Olfaction originates with air particles travelling from an external environment to the upper segment of the human nose. This phenomenon is generally understood by using the nasal airflow dynamics, which enhances the olfaction by creating the vortices in the human nose. An anatomical three-dimensional model of the human nasal cavity from computed tomography (CT) scan images using the MIMICS software (Materialise, USA) was developed in this study. Grid independence test was performed through volume flow rate, pressure drop from nostrils and septum and average velocity near the nasal valve region using a four computational mesh model. Computational fluid dynamics (CFD) was used to examine the flow pattern and influence of airflow dynamics on vortices in the nasal cavity. Numerical simulations were conducted for the flow rates of 7.5, 10, 15 and 20 L/min using numerical finite volume methods.

At coronal cross-sections, dissimilar nasal airflow patterns were observed for 7.5, 10, 15 and 20 L/min rate of fluid flow in the human nasal cavity. Vortices that are found at the boundaries with minimum velocity creates deceleration zone in the nose vestibule region, which is accompanied by flow segregation. Maximum vortices were observed in the nasal valve region and the posterior end of the turbinate region, which involves mixing and recirculation and is responsible for enhancing the smelling process.

The proposed analysis is applicable to design the sensor chamber for electronic noses.

In this paper, the influence of airflow dynamics on vortices in the human nasal cavity is discussed through numerical simulations.

The paper aims to focus on airflow and heat transfer inside the human nasal cavity. The contribution of this work is the inertial analysis of the momentum and thermal stress of the cavity throughout the respiratory cycle.

By means of computer tomography scans, an accurate three‐dimensional anatomical representation of the human nasal cavity was obtained. A three‐dimensional numerical model is presented in order to predict the time evolution of flow patterns during a quiet breathing cycle, covering inhalation and exhalation. An inertial analysis of the momentum and a detailed study of the thermal behaviour during the breathing cycle is carried out.

Head loss, velocity and temperature values are in agreement with experimental results from previous studies. Based on these results, the influence of the inhalation and the exhalation on the flow pattern and air conditioning has been reviewed. Results suggest that the anterior and posterior turbinate regions are where the air conditioning is primarily produced.

The future goal is to investigate respiratory disorders to increase the effectiveness of the eventual treatment of the pathology. The model could be a useful tool to predict, for instance, the modification of the flow patterns due to septal perforations.

The transient resolution provides insight into the momentum and thermal inertia though the breathing which is far from being well understood.

In nature the siting of the organs responsible for picking up odours is very variable. In vertebrate animals such as man, the forward part of the head, usually just above the mouth is the invariable site. In the invertebrates this is far from the case. In the insects, odours are sensed by the antennae or feelers which project forward from the head. In the various worms the sensory cells are sited in pits on the side of the head and in flies they are even found on the feet. In each case, however, nature has contrived to locate these sensory organs in the most appropriate place where they can provide the maximum of information. Basically, in man the receptor area for smell is an off‐shoot of the respiratory system. (Fig. 1) A smell, odour, aroma — call it what you will — consists essentially of particles of gas and vapour and, as such, one cannot be aware of its presence until some of it enters the nasal cavity either via the nose, or, alternatively, by the back of the mouth.

As their name implies, the prime function of these ingredients is to donate flavour which is detected by the senses of taste and smell. Taste itself is made up of the four primary tastes — sweet, sour, salt and bitter — which are detected by the taste buds situated in the mouth, mainly on the tongue, palate and cheeks. Smell is detected by extremely sensitive cells at the top of the nasal cavity. The current standard definition of flavour is as follows: ‘Flavour is the sensation elicited by a foodstuff when the taste and odour receptors are stimulated’.

The Secretary of State for Social Services, in exercise of his powers under sections 56 and 85 of the National Insurance (Industrial Injuries) Act 1965(a) and section 57 of that Act as modified by section 8 of the National Insurance Act 1966(b) and of all other powers enabling him in that behalf, after reference to the Industrial Injuries Advisory Council, hereby makes the following regulations:—

Less lethal weapons have become a critical tool for law enforcement when confronting dangerous, combative individuals in the field. The purpose of this paper is to review the medical aspects and implications of three different types of less lethal weapons.

The paper conducted a comprehensive medical literature review on blunt projectiles, irritant sprays including oleoresin capsicum (OC), and conducted energy devices such as the Taser™. It reviews the history, mechanisms of action, intended and other physiologic effects, and medical safety risks and precautions of these devices. In particular, the paper focuses on the issue of sudden in‐custody death and less lethal weapons, reviewing case reports, animal research and human investigative studies on this topic.

In general, these three different types of less lethal weapons have been effective for their intended use. Each type of less lethal weapon has a number of physiologic effects and specific medical issues that must be considered when the weapon is used. There is no clear evidence that these devices are inherently lethal, nor is there good evidence to suggest a causal link between sudden in‐custody death and the use of irritant sprays or conducted energy devices.

While further research on the physiologic effects of these devices is needed, this paper provides law enforcement with a medical review of less lethal weapons including blunt projectiles, irritant sprays such as OC, and conducted energy devices such as the Taser.

The purpose of this paper is to illustrate how biomimetics can be applied in sensor design. Biomimetics is an engineering discipline that uses nature as an inspiration source for generating ideas for how to solve engineering problems. The paper reviews a number of biomimetic studies of sense organs in animals and illustrates how a formal search method developed at University of Toronto can be applied to sensor design.

Using biomimetics involves a search for relevant cases, a proper analysis of the biological solutions, identification of design principles and design of the desired artefact. The present search method is based on formulation of relevant keywords and search for occurrences in a standard university biology textbook. Most often a simple formulation of keywords and a following search is not enough to generate a sufficient amount of useful ideas or the search gives too many results. This is handled by a more advanced search strategy where the search is either widened or it is focused further mainly using biological synonyms.

A major problem in biomimetic design is finding the relevant analogies to actual design tasks in nature.

Biomimetics can be a challenge to engineers due to the terminology from another scientific discipline.

Using a formalised search method is a way of solving the problem of finding the relevant biological analogies.

The paper is of value as most present biomimetic research is focused on the understanding of biological phenomena and does not have as much focus on the engineering design challenges.

Whereas a draft of the following Scheme was laid before Parliament and approved by a resolution of each House of Parliament: