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This paper addresses the relationship between temperature or relative humidity and the number of patients seen and how often the treating physician deemed it necessary to transport the patient to the hospital. A retrospective review was performed on 251 patients seen at the Dayton airshow during the 2‐day period of 21‐22 July 2001. The air show has an attendance of approximately 50,000 people spread out through this 3‐day event. The first aid tents that provide the medical care at the air show are staffed by either senior emergency medicine residents or emergency medicine attendings. Results showed that the relationship between the number of patients transported and the temperature reveals a pattern of more patients being transported as the temperature increases.

The purpose of this paper is to study the effects of ion‐slip current and Hall current on the formation of longitudinal vortices in natural convection flow over a heated horizontal plate.

The criterion on the position marking on the onset of longitudinal vortices is defined in the present paper. The results show that the onset position characterized by the Grashof number depends on the Prandtl number, the Reynolds number, the wave number, the Hall parameter, the ion‐slip parameter, and the Hartmann number.

The flow becomes more stable as the magnetic field increases. However, the destabilizing effect is found on the flow when the Hall and ion‐slip currents are presented.

The standard method of linear stability model is applied, with terms higher than first order in disturbance quantities being neglected.

The problem of MHD natural convection flow with Hall and ion‐slip currents has many important engineering applications, e.g. power generators, Hall accelerators and flows in channels and ducts.

This study is to check the validity of the assumptions that the conditions of Hall and ion‐slip currents can be ignored.

A finite element method for the analysis of combined radiative and conductive heat transport in a finite axisymmetric configuration is presented. The appropriate integro‐differential governing equations for a grey and non‐scattering medium with grey and diffuse walls are developed and solved for several model problems. We consider axisymmetric, cylindrical geometries with top and bottom boundaries of arbitrary convex shape. The method is accurate for media of any optical thickness and is capable of handling a wide array of axisymmetric geometries and boundary conditions. Several techniques are presented to reduce computational overhead, such as employing a Swartz‐Wendroff approximation and cut‐off criteria for evaluating radiation integrals. The method is successfully tested against several cases from the literature and is applied to some additional example problems to demonstrate its versatility. Solution of a free‐boundary, combined‐mode heat transfer problem representing the solidification of a semitransparent material, the Bridgman growth of an yttrium aluminium garnet (YAG) crystal, demonstrates the utility of this method for analysis of a complex materials processing system. The method is suitable for application to other research areas, such as the study of glass processing and the design of combustion furnace systems.

The purpose of this paper is to evaluate the thermal and fluid dynamic behaviors of natural convection in a vertical channel‐chimney system heated symmetrically at uniform heat flux in order to detect the different fluid motion structures inside the chimney, such as the cold inflow from the outlet section of the chimney and the reattachment due to the hot jet from the channel, for different extension and expansion ratios of the adiabatic extensions.

The model is constituted by two‐dimensional steady‐state fully elliptic conservation equations which are solved numerically in a composite three‐part computational domain by means of the finite‐volume method.

Stream function and temperature fields in the system are presented in order to detect the different fluid motion structures inside the chimney, for different extension and expansion ratios of the adiabatic extensions. The analysis allows to evaluate the effect of the channel aspect ratio on the thermal and fluid dynamic behaviors on a channel‐chimney system and thermal and geometrical conditions corresponding to a complete downflow. Guidelines to estimate critical conditions related to the beginning of flow separation and complete downflow are given in terms of order of magnitude of Rayleigh and Froude numbers.

The hypotheses on which the present analysis is based are: two‐dimensional, laminar and steady‐state flow, constant thermophysical properties with the Boussinesq approximation. The investigation is carried out in the following ranges: from 100 to 100,000 for the Rayleigh number, from 5.0 to 20 for the aspect ratio, from 1.0 to 4.0 for the expansion ratio and from 1.5 to 4 for the extension ratio.

Thermal design of heating systems in different technical fields, such as in electronic cooling and in building ventilation and houses solar components, evaluation of heat convective coefficients and guidelines to estimate critical conditions related to the beginning of flow separation and complete downflow.

The paper is useful to thermal designers because of its evaluation of the thermal and velocity fields, correlation for the Nusselt number and guidelines criteria in terms of Rayleigh and Froude numbers to evaluate conditions of flow separation and complete downflow in natural convection in air for vertical channels‐chimney systems.

Using a dynamic capabilities lens, this paper aims to study the impact of genomics generally and gene therapy specifically on the rare disease sector of the biopharmaceutical industry.

In this study, 24 genomics-based, rare disease-focused biopharma companies were studied and several variables were tested with respect to enterprise value growth. The companies were analyzed as a group of rare disease firms, as well as by size.

The authors found that number of employees, revenues, number of pipeline and marketed products and retained earnings are strongly correlated (in that order) with enterprise value in rare disease focused biopharma companies. These correlations seem to be weaker as a company’s market capitalization size decreases, indicating that there tends to be increasing returns to scale.

This study found that increasing rates of cumulative returns to enterprise value growth depends on accumulating knowledge-based employees and expanding product portfolios of disruptive genomics-based technologies for treating rare diseases. Aggregating skilled and innovative employees (especially in bigger companies) can be seen as a cumulative bolstering factor in leveraging dynamic capabilities which can be recognized, understood and transformed into commercial success (i.e. increasing returns in enterprise value). In other words, technology managers’ job is to manage not only the financial aspects of the technology but also human resources, asset configuration and strategic alliances efficiently toward faster and better innovation. Strong dynamic capabilities can be formed with the accumulation of experience, articulation and codification of knowledge and an adaptive ability to change the way they solve problems as their environment transforms.

This is the first study to demonstrate and measure a relationship between dynamic capabilities and enterprise value in genomics-based rare disease firms. Further, this study highlights the importance of building the capability and capacity to absorb expertise and accumulate knowledge for new product innovations and sustainable competitive advantage in industries characterized by disruptive innovation.

A detailed review of the archival literature on: fluid dynamics, heat transfer and shape optimization reveals that the optimal shape of natural convective cavities has not been investigated so far, and of course, its physical features are not understood. A prominent application of cavities cooled by natural convection arises in the miniaturization of electronic packaging where some type of temperature constraint must be applied at the directly heated wall. This contemporary issue has been addressed in the present work in an elegant manner by linking a code on computational fluid dynamics with a shape optimization code. Once the velocity and temperature fields were accurately computed for an initial cavity with a certain heat load, a two‐step optimization procedure was implemented in a methodical fashion. A first optimization sub‐problem transformed a square cavity into a rectangular cavity, while the second optimization sub‐problem sculpted the shape of the upper horizontal insulated wall in order to bring down the maximum wall temperature of the directly heated vertical wall, i.e. the so‐called “hot spot”. A bird's eye inspection of the numerical results revealed that the first optimization sub‐problem produced a significant reduction in area (volume), while raising the maximum wall temperature of the heated vertical wall by a small amount. The second optimization sub‐problem supplied a remarkable decrease in the maximum wall temperature of the heated vertical wall, carrying with it a moderate increase in area (volume). At the end, the optimal shape of the cavity turns out to be a disfigured vertical rectangular cavity in which the upper insulated wall forming a parabolic‐skewed cap.

Purpose: An examination of the uptake and application of Robotic, Artificial Intelligence and Service Automation (RAISA) technologies by the events industry.

Design/methodology/approach: Academic and practitioner literature review and analysis pertaining to the relevance of RAISA in events.

Findings: The events industry has tended to rely on automation in staging and event production and the application of RAISA in events has been limited but holds great potential for the future. Whereas, in the hospitality and tourism industries RAISA has been applied across a range of service functions. For example, in such industries, artificial intelligence, machine learning and service robotics technologies have become commonplace. Nonetheless, the same level of adoption of RAISA in events is less evident particularly in front-of-house operation, due largely to the incompatibility with the raison d'être of event attendance – the purposive congregation of people seeking an event experience.

Research limitations/implications: The findings are the views of the authors and are therefore reliant upon existing events management literature on RAISA and their interpretation of this information and its application to the events industry.

Practical implications: RAISA has the capacity to play a crucial technical function in the events industry. However, it needs to be acknowledged that an event is essentially an experiential product which is simultaneously delivered and consumed in a particular setting/venue. RAISA applications and techniques avail event management immense sustainability and growth potential.

Social implications: Events are expressions of human social interactions and activities. Given the recent trend in sports media consumption as a substitute for live event attendance compounded by barriers to event attendance such as heightened terrorism threat and high expense/cost, there is a real risk of degradation of the social significance of the events industry. The prudent uptake of RAISA has the potential to emolliate the barriers to attendance while facilitating effective marketing and industry sustainability.

Originality/value: This chapter provides a new perspective in focusing on the potential applicability of RAISA in event management practice.

In their recent book, Dead Man Working, Carl Cederström and Peter Fleming paint a haunting picture of the contemporary employee: sleep deprived and overworked, exhausted and strung out, unable to tell where work ends and where life begins, hardly alive and yet unable to die. In this paper, the author widens the picture by examining the systemic effects of contemporary work on the family. Drawing upon ideas from psychoanalysis and critical theory, the author reveals how the extraction of life by work reverberates across generations and seeps into the home environment. The author also reveals how new constellations of family reinforce deadening work. What emerges is a family portrait known as the “dead family working.”

Research on natural convection in open channels is very extensive due to its role in many engineering applications such as thermal control of electronic systems. In this paper, a parametric analysis is carried out in order to add knowledge of heat transfer in air natural convection for a symmetrically heated vertical parallel plate channel with a central auxiliary heated or adiabatic plate. The two‐dimensional steady‐state problem is solved by means of the stream function–vorticity approach and the numerical solution is carried out by means of the control volume method. Results are obtained for both a heated and unheated auxiliary plate, for a Rayleigh number in the range 10³–10⁶, for a ratio of the auxiliary plate height to the channel plate height equal to 0, 0.5 and 1 and for a ratio of the channel length to the channel gap in the range 5–15. Correlations for maximum wall temperatures and average channel Nusselt numbers are proposed.

To address the impact of adding insulated plate extensions at the entrance of an isoflux vertical parallel‐plate channel on the thermal performances of natural convection in air for these systems.

The model relies on the full elliptic conservation equations which are solved numerically in a composite three‐part computational domain by means of the finite‐volume method.

Results are reported in terms of wall temperatures, induced mass flow rates, as well as velocity and temperature profiles of the air for various thermal and geometric parameters. The wall temperatures increase when the extensions are appended at the inlet of the channel. Wall temperature profiles strongly depend on the Rayleigh number and the dependence of the heated channel aspect ratio is weaker than the extension ratio. Velocity and temperature profiles modify inside the heated channel due to the thermal development. In addition, correlation equations for main engineering quantities, such as the induced mass flow rate, average Nusselt number and dimensionless maximum wall temperature in terms of the channel Rayleigh number, channel aspect ratio and extension ratio are presented.

The investigation has been carried out in the following ranges: 10³‐10⁵ for the Rayleigh number, 5.0‐15.0 for the channel aspect ratio and 1.0‐5.0 for the extension ratio. The hypotheses on which the present analysis is based are: two‐dimensional, laminar and steady‐state flow, constant thermophysical properties with the Boussinesq approximation.

Thermal design of heating systems in manufacturing processes, evaluation of heat convective coefficients and maximum attained wall temperatures.

Evaluation of the thermal and velocity fields and correlation equations for the Nusselt number and maximum dimensionless temperatures in natural convection in air for vertical channels. The paper is useful to thermal designers.