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The purpose of this study is to investigate the transport phenomena of smoke flow in a semi-open vertical shaft.

The large eddy simulation (LES) method was used to model the movement of fire-induced thermal flow in a full-scale vertical shaft. With this model, different fire locations and heat release rates (HRRs) were considered simultaneously.

It was determined that the burning intensity of the fire is enhanced when the fire attaches to the sidewall, resulting in a larger continuous flame region in the compartment and higher temperatures of the spill plume in the shaft compared to a center fire. In the initial stage of the fire with a small HRR, the buoyancy-driven spill plumes incline toward the side of the shaft opposite the window. Meanwhile, the thermal plumes are also directed away from the center of the shaft by the entrained airflow, but the inclination diminishes as HRR increases. This is because a greater HRR produces higher temperatures, resulting in a stronger buoyancy to drive smoke movement evenly in the shaft. In addition, a dimensionless equation was proposed to predict the rise-time of the smoke plume front in the shaft.

The results need to be verified with experiments.

The results could be applied for design and assessment of semi-open shafts.

This study shows the transport phenomena of smoke flow in a vertical shaft with one open side.

The purpose of this paper is to present a fast and bare bones implementation of a numerical method for quickly simulating turbulent thermal flows on GPUs. The work also validates earlier research showing that the lattice Boltzmann method (LBM) method is suitable for complex thermal flows.

A dual lattice hydrodynamic (D3Q27) thermal (D3Q7) multiple-relaxation time LBM model capable of thermal DNS calculations is implemented in CUDA.

The model has the same computational performance compared to earlier publications of similar LBM solvers. The solver is validated against three benchmark cases for turbulent thermal flow with available data and is shown to be in excellent agreement.

The combination of a D3Q27 and D3Q7 stencil for a multiple relaxation time -LBM has, to the authors’ knowledge, not been used for simulations of thermal flows. The code is made available in a public repository under a free license.

The purpose of this paper is to present a procedure to design an experimental setup meant to validate an innovative approach for simulating, via computational fluid dynamics, a high-pressure gas release from a rupture (e.g. on an offshore oil and gas platform). The design is based on a series of scaling exercises, some of which are anything but trivial.

The experimental setup is composed of a wind tunnel, the instrumented scaled (1:10) mock-up of an offshore platform and a gas release system. A correct scaling approach is necessary to define the reference speed in the wind tunnel and the conditions of the gas release to maintain similarity with respect to the real-size phenomena. The scaling of the wind velocity and the scaling of the gas release were inspired by the approach proposed by Hall et al. (1997): a dimensionless group was chosen to link release parameters, wind velocity and geometric scaling factor.

The theoretical scaling approaches for each different part of the setup were applied to the design of the experiment and some criticalities were identified, such as the existence of a set of case studies with some release parameters laying outside the applicability range of the developed scaling methodology, which will be further discussed.

The resulting procedure is one of a kind because it involves a multi-scaling approach because of the different aspects of the design. Literature supports for the different scaling theories but, to the best of the authors’ knowledge, fails to provide an integrated approach that considers the combined effects of scaling.

The architecture, engineering and construction industry faces several challenges when performing life-cycle cost calculations. On the basis of activity theory, this study aims at improving our understanding of the current cost calculation in design practices as an activity system with a number of built-in contradictions.

Drawing on one of the authors’ practical experience from a design office, the research design comprises a paradigmatic case study of a Danish architecture firm, in which data are gathered through documents, observations, interviews and physical artefacts. Moreover, this paper applies a literature review on barriers for adopting life-cycle costing.

The paper identifies a number of primary, secondary, tertiary and quaternary contradictions between practices of design, cost calculations and data management. Thus, hypotheses are formulated on how and to what extent these different contradictions shape cost calculations in design practices to obstruct or support the application of life cycle costing principles in design.

This study is part of an ongoing research project. Thus, additional analysis is required before the authors may conclude on final results.

This paper identifies a number of factors that obstruct or support the implementation of life cycle costing in current design practices.

This paper provides new insights into the various contradictions that shape data management in architectural offices as a prerequisite for improving life cycle design practices.

This paper aims to examine the time it would take to provide medical prophylaxis for a large urban population in the wake of an airborne anthrax attack and the effect that various parameters have on the total logistical time.

A mathematical model that evaluates key parameters and suggests alternatives for improvement is formulated. The objective of the model is to minimize the total logistical time required for prophylaxis by balancing three cycles as follows: the loading cycle, the shipping cycle and the service cycle.

Applying the model to two representative cases reveals the effect of various parameters on the process. For example, the number of distribution centers and the number of servers in each center are key parameters, whereas the number of central depots and the local shipping method is less important.

Various psychological factors such as mass panic are not included in the model.

There are few papers analyzing the logistical response to an anthrax attack, and most focus mainly on the strategic level. The study deals with the tactical logistical level. The authors focus on the distribution process of prophylaxis and other medical supplies during the crisis, analyze it and identify the parameters that influence the time between the detection of the attack and the provision of effective medical treatment to the exposed population.

It's hard to envision a system more global and more integrated than research. Many stakeholders affect and are affected by changes in the research ecosystem; the ecosystem differs in significant ways across the globe and between researchers, institutions and fields of study; and there are many questions that exclusive action can't address. There are also broad ecosystem-level questions that need answering. For these reasons alone, global approaches to reform are needed.

The first step in this exploration isn't to start looking for “solutions”, but to develop a better understanding of how our needs and interests overlap. By identifying the broad contours of common ground in this conversation, we can build the guardrails and mileposts for our collaborative efforts and then allow the finer-grained details of community-developed plans more flexibility and guidance to evolve over time.

What are these overlapping interests? First, the people in this community share a common motive – idealism – to make research better able to serve the public good. We also share a common desire to unleash the power of open to improve research and accelerate discovery; we are all willing to fix issues now instead of waiting for market forces or government intervention to do this for us; and we want to ensure that everyone everywhere has equitable access to knowledge.

There is also very broad agreement in this community about which specific problems in scholarly communication need to be fixed and why, and well as many overlapping beliefs in this community. OSI participants have concluded that four such beliefs best define our common ground: (1) research and society will benefit from open done right; (2) successful solutions will require broad collaboration; (3) connected issues need to be addressed, and (4) open isn't a single outcome, but a spectrum.

OSI has been observing and debating the activity in scholarly communication since late 2014 with regard to understanding possible global approaches and solutions for improving the future of open research. While the COVID-19 pandemic has made the importance of open science abundantly clear, the struggle to achieve this goal (not just for science but for all research) has been mired in a lack of clarity and urgency for over 20 years now, mostly stalling on the tension between wanting more openness but lacking realistic solutions for making this happen on a large scale with so many different stakeholders, needs and perspectives involved.

Underlying this tension is a fundamental difference in philosophy: whether the entire scholarly communication marketplace, driven by the needs and desires of researchers, should determine what kind of open it wants and needs; or whether this marketplace should be compelled to adopt open reform measures developed primarily by the scholarly communication system's main billpayers-funders and libraries. There is no widespread difference of opinion in the community whether open is worth pursuing. The debate is mostly over what specific open solutions are best, and at what pace open reforms should occur.

OSI has proposed a plan of action for working together to rebuild the future of scholarly communication on strong, common ground foundation. This plan – which we're referring to as Plan A – calls for joint action on studies, scholarly communication infrastructure improvement, and open outreach/education. Plan A also calls for working together with UNESCO to develop a unified global roadmap for the future of open, and for striving to ensure the community's work in this space is researcher-focused, collaborative, connected (addressing connected issues like peer review), diverse and flexible (no one-size-fits-all solutions), and beneficial to research. UNESCO's goal is to finish its roadmap proposal by early 2022.

For a full discussion of OSI's common ground recommendations, please see the Plan A website at http://plan-a.world.

For the purpose of reducing the incidence of hazardous materials transport accident, eliminating the potential threats and ensuring their safety, aiming at the shortcomings in the process of current hazardous materials transportation management, this paper aims to construct the framework of hazardous materials transportation safety management system under the vehicle-infrastructure connected environment.

The system takes the intelligent connected vehicle as the main supporter, integrating GIS, GPS, eye location, GSM, networks and database technology.

By analyzing the transportation characteristics of hazardous materials, this system consists of five subsystems, which are vehicle and driver management subsystem, dangerous sources and hazardous materials management subsystem, route analysis and optimization subsystem, early warning and emergency rescue management subsystem, and basic information query subsystem.

Hazardous materials transportation safety management system includes omnibearing real-time monitoring, timely updating of system database, real-time generation and optimization of emergency rescue route. The system can reduce the transportation cost and improve the ability of accident prevention and emergency rescue of hazardous materials.

The purpose of this paper is to introduce and discuss potential applications of emerging Building Information Model (BIM) and related technologies as applied to healthcare facilities. The paper presents example of applications of digital tools enabled by BIM that support more integrated outcomes for complex healthcare projects.

Paper formulation by a transdisciplinary author group with ideas and approaches developed through discussions and writing to explore future research directions. Initial ideas are supplemented by a literature review with examples introduced where relevant.

BIM as a front-end construction engineering tool is quite mature. Application of BIM and related tools to support complex healthcare at the precinct scale, for facilities management (FM), including improved user experience (UX) has been limited but shows great promise to support complex healthcare projects.

The research presented is limited and exploratory as it represents the first step by this group to investigate an integrated approach to digital healthcare design and FM.

The paper introduces the considerable benefits of BIM models, and related tools for FM and/or UX (both staff and patients) to save time, money and improves efficiency and accuracy in healthcare facilities.

The transdisciplinary author group brought broad perspectives to the potential benefits of combining accurate data-rich legacy building models with other digital tools for increased integration and co-ordination at all life stages of a healthcare precinct.

The purpose of this paper is to introduce an approach in measuring the shielding gas flow within laser powder bed fusion (L-PBF) machines under near-process conditions (regarding oxygen content and shielding gas flow).

The measurements are made sequentially using a hot-wire anemometer. After a short introduction into the measurement technique, the system which places the measurement probe within the machine is described. Finally, the measured shielding gas flow of a commercial L-PBF machine is presented.

An approach to measure the shielding gas flow within SLM machines has been developed and successfully tested. The use of a thermal anemometer along with an automated probe-placement system enables the space-resolved measurement of the flow speed and its turbulence.

The used single-normal (SN) hot-wire anemometer does not provide the flow vectors’ orientation. Using a probe with two or three hot-films and an improved placement system will provide more information about the flow and less disturbance to it.

A measurement system which allows the measurement of the shielding gas flow within commercial L-PBF machines is presented. This enables the correlation of the shielding gas flow with the resulting parts’ quality.

The purpose of this paper is to investigate the major political and economic changes in the world and the likely impact that these changes will bring to tourism and hospitality industries.

The paper adopts a geopolitical perspective on the dynamics of tourist flows, stipulating that geopolitics has a major impact on the size, structure, and direction of these flows.

The paper identifies six geopolitical drivers of tourist flows in the future, namely: the fall of the American Empire, the rise of the BRIC and the PINE countries, increased global political instability, increased importance of regional supranational organisations, greater control of the individuals on a global scale, and the greater importance and power of corporations than national governments.

The paper critically evaluates the geopolitical drivers of tourist flows, their likely future development and the impact they have on tourism.