Building Fire Evacuation: An IoT-Aided Perspective in the 5G Era

Complex and tall buildings have been constructed in many cities recently. Fire safety should be a major concern of building designers, engineers, and governments. Previous fire experience has made us understand the importance of acquiring fire-ground information to facilitate firefighting operations, evacuation processes, rescues, etc. Recently, the rapid advancement in Information Technology, Data Analytics, and other detection and monitoring systems has provided the basis for fire safety researchers to re-think fire safety strategies in the built environment. Amongst all fire safety studies, evacuation in tall buildings, including elevator evacuations, has attracted much attention. IoT-aided building fire evacuation is a new concept of the building evacuation mode, which improves the building evacuation process by making decisions of escape based on the real-time fire-ground information, such as the fire environment and occupant situations. Focusing on IoT applications in building fire evacuation, this paper explores the advantages and insufficiencies of current smart building fire evacuation systems. A conceptual design of an IoT-aided building fire evacuation control system is described. The system is introduced in the sequence of information needs, information sources and data transmission, and potential services and applications. Finally, new insights into promising 5G technologies for future building fire evacuations are discussed.

MATHEMATICAL MODEL OF THE INTERACTION OF THE SCREW WORKING BODIES OF FOREST FIRE GROUND-THROWING MACHINES WITH THE GROUND COVER

The paper provides an overview of research on the working processes of screw working bodies of technological machines. It is noted that at present such important issues in the theory of auger working bodies as the required number of auger turns, the required position of the auger spiral in relation to the center, etc. have not been fully resolved, since the solution of these issues can provide an increased productivity of the tool. A structural and technological scheme of a forest fire machine with multifunctional modules is proposed, which consists of auger working bodies, which can be changed modularly with a screw metal thread for a brush, depending on the area and type of soil, the rotor of the thrower, with the ability to drive the cutters-throwers and auger working bodies both from the power take-off shaft of the tractor, and using a hydraulic motor, a guide casing. A mathematical model of an auger working body with a hydraulic drive has been compiled for removing the ground cover with forest litter when extinguishing forest fires with a ground gun, so that combustible materials do not fall into the fire zone together with the soil flow from the rotor-thrower. The working process of the hydraulic drive of the auger working bodies of a forest fire ground-sweeping machine is described by a system of differential equations, including the equations of translational and rotational movements of the auger working body and the equation of the flow rate of the working fluid. The problem of optimization of kinematic and dynamic parameters of auger working bodies of forest fire ground-sweeping machine is set

MATHEMATICAL MODEL OF THE OPERATING PROCESS OF THE ROTOR-THROWING MACHINE

The work describes theoretical studies of mathematical, physical and simulation models for studying ground-throwing equipment, in particular, the interaction of the rotor of the thrower with the soil. Changes and innovations carried out by the world community are developing in many directions related to the protection of forests from uncontrolled forest fires. The spread of an uncontrolled forest ground fire over a combustible biofuel occurs by running raids along the litter and along the bases of tree trunks at different speeds, and the height of the flame without taking measures will reach the top of the tree. We have proposed a version of a forest fire ground gun that performs a technological process with the rise of a soil layer above the soil surface, and then a three-stage rotor-thrower ejects the soil in a given direction. The process of throwing soil in an amount sufficient to extinguish the forest ground edge of the fire is a complex system of interaction of the working body with the medium of bulk elements. The main problem, in our opinion, is associated with the insufficient volume supplied by the existing units. On the issue of formalized modeling of soil movement during the operation of the rotor of a forest fire ground gun. With the modern development of digital technologies, the decision-making process on how to modernize technical equipment is unthinkable without designing a workflow. For the constant development of the model, formal relations should contain parameters characterizing the influence of the equipment operating conditions. Thus, the continuous computational experiment will allow not only to estimate the parameters of the working process, but also to manage the optimization of the model itself to determine the most effective values of its parameters. At the first stage of modeling, it was decided that the main parameter of the modernization efficiency would be the value of the average range of the ground flight. Formula relations for the model were obtained within the framework of the physics of the flight of a material point at an angle to the horizon with a minimum influence of the external environment (negligible air viscosity). At the first stage of modeling using spreadsheets, the dependence p (t) was estimated using spreadsheets, which showed that the pressure in the system stabilizes in fractions of a second. So, using the model relations, it is possible to determine in the result of a computational experiment the value of the average range of the ground flight

Expert knowledge elicitation in the firefighting domain and the implications for training novices

Background/Purpose Experienced firefighters often make important decisions in fast-paced fire ground environments characterised by uncertainty and evolving conditions, mostly under considerable time-pressure. The nature of these environments inadvertently presents firefighters with novel situations that occasionally challenge their expertise, subsequently necessitating a reliance on intuitive as opposed to rational decisions. The purpose of this study is to elicit the tacitly held knowledge and intuitive thought processes that were used by 31 experts while managing a range of complex, non-routine fire incidents. Design/Methodology/Approach The study used a formal knowledge elicitation technique known as the critical decision method (CDM). CDM is a qualitative strategy that applies a set of cognitive probes to explore the cognitive processes that aid the performance of a complex task. This method was preferred to other cognitive task analysis methods as it specifically favours the use of retrospective incident accounts and incidents that were both challenging and memorable. Using the full CDM protocol, 31 experienced firefighters were interviewed across various fire stations in the UK and Nigeria (UK = 15, Nigeria = 16). The interview transcripts were coded, categorised and analysed using the emergent themes analysis approach. Findings The results from the study identified 134 decision points across the 31 incident accounts. A total of 42 salient cues sought by experts at each decision point were revealed and organised into a critical cue inventory. The identified cues were subsequently categorised into five distinct types based on the type of information each cue relayed to an incident commander. The study further developed a decision-making model – information filtering and intuitive decision-making model – that describes how experienced firefighters made difficult fire ground decisions amidst multiple informational sources. The model ultimately showed experts’ preferences for intuitive decisions as the default-thinking mode, with deliberation only required on few instances as conditions warranted. The study also compiled and indexed the cognitive strategies elicited from the expert firefighters into a competence assessment framework. Practical Implications In light of existing debate about the accessibility of expert knowledge, the current study not only provides empirical evidence detailing the practical application of the CDM as a formal knowledge elicitation method but also delineates a range of cognitive outputs from the elicitation process that ultimately holds relevance for knowledge transfer from expert to novices. The study identified a range of training needs and discussed the practical implications of transferring expert knowledge into learning tasks that could subsequently aid the cognitive development of novices. In particular, the study proposed adopting the four-component instructional design model in organising the CDM outputs for training purposes. Originality/Value While it is generally taken that experts, because of their extensive domain knowledge and well-developed schema, often perform considerably (and sometimes exceptionally) well when solving complex problems, finding a credible and objective method to model what experts know and do continues to pose a challenge, particularly when such revelation is crucially required for training purposes. This study is therefore timely since its tacit and intuitive knowledge outputs can now be applied to enhance the development of training curricula for novices. The learning tasks developed from the CDM outputs are hoped to facilitate organisational learning not only within the firefighting domain but also across other high reliability organisations. It is extremely important that expert knowledge is preserved in these domains especially in countries such as the UK, where the rate of real fires has been on decline, which in turn suggests that the quality of experiential knowledge required to manage complex non-routine fire cases may also be on decline. The current study also presents and discusses insights based on the cultural differences observed between the UK and the Nigerian fire services.

Disturbance history modulates how litter and herbaceous cover influence conifer regeneration after fire

Climate-driven increases in disturbance frequency and extent augment the potential for compounded disturbances. Drawing on well-studied forests that experienced successive disturbances, we asked: (1) how does post-fire cover of litter, herbaceous cover and bare ground vary between stands affected by combinations of blow-down, insect outbreak, and fire? (2) How do post-fire relationships between ground cover and conifer regeneration vary with recent disturbance history? We measured ground cover and conifer regeneration from 2003 to 2014 following stand-replacing fires in 2002. Burned stands were either blown down in 1997, affected by a 1940s Dendroctonus rufipennis (spruce beetle; SB) outbreak, or neither. Implementing mixed-effects models, we measured the relationships between pre-fire stand attributes (structural stage, canopy dominance and combination of disturbances) and post-fire ground cover and between post-fire ground cover and conifer regeneration. Fire-only stands had more litter and herbaceous cover post fire than other stands (P<0.05). Fir regeneration increased with litter in stands that only burned, but decreased with litter in stands that were first blown down. Similarly, pine and fir regeneration increased with herbaceous cover after fire-only, but did the opposite in stands affected by the SB outbreak. Pre-fire legacies can modulate the effects of ground cover on plant regeneration.

Impact of Fire Attack Utilizing Interior and Exterior Streams on Firefighter Safety and Occupant Survival: Water Mapping

As research continues into how fire department interventions affect fire dynamics in the modern fire environment; questions continue to arise on the impact and implications of interior versus exterior fire attack on both firefighter safety and occupant survivability. Previous research into various types of fire ground ventilation, flow paths, and exterior fire streams has provided the fire service with an increased understanding of fire dynamics. However, in some instances, the information from the studies may not support current, experienced-based practices. This gap between the research to date and the fire ground suppression experience has driven the need for further study. Therefore, research into the various methods of fire attack will allow a broader understanding of how firefighter interventions on the fire ground can impact the outcome of both life safety and property protection. This study will build upon the fire research conducted to date by analyzing how firefighting tactics, specifically different fire suppression tools and tactics, affect the thermal exposure and survivability of both firefighters and building occupants and affect fire behavior in structures. The purpose of this study is to improve firefighter safety, fireground tactics, and the knowledge of fire dynamics by providing the fire service with scientific information, developed from water flow and full-scale fire testing, in representative single-family homes. The project will be comprised of 3 parts: • Part I: Water Distribution • Part II: Air Entrainment • Part III: Full-Scale Residential Fire Experiments This report details the results and analysis from the water distribution experiments. These tests were conducted without the presence of fire to gain a fundamental understanding of water flows into compartments. Each test was designed to quantify water distribution within a compartment by evaluating the differences caused by various application methods, hose stream types, nozzle movements, pressures/flow rates, stream locations and elevation angles.

Impact of Fire Attack Utilizing Interior and Exterior Streams on Firefighter Safety and Occupant Survival: Air Entrainment

As research continues into how fire department interventions affect fire dynamics in the modern fire environment, questions continue to arise on the impact and implications of interior versus exterior fire attack on both firefighter safety and occupant survivability. Previous research into various types of fire ground ventilation, flow paths, and exterior fire streams has provided the fire service with an increased understanding of fire dynamics. However, in some instances, the information from the studies did not support current, experience-based practices. This gap between the research to date and the fire ground suppression experience has driven the need for further study. This study will build upon the fire research conducted to date by analyzing how firefighting tactics, specifically different fire suppression tools and tactics, affect the thermal exposure and survivability of both firefighters and building occupants and affect fire behavior in structures. The purpose of this study is to improve firefighter safety, fire ground tactics, and the knowledge of fire dynamics by providing the fire service with scientific information, developed from water flow and full-scale fire testing, in representative single-family homes. This study will build and expand upon the fire research conducted to date by analyzing how firefighting tactics, specifically suppression methods, affect the thermal exposure and survivability of both firefighters and building occupants in addition to impacting fire behavior in structures. The purpose of this study is to improve firefighter safety, fireground tactics, and the knowledge of fire dynamics by providing the fire service with credible scientific information, developed from both water flow and full-scale fire testing, in representative single family homes. The project is comprised of 3 parts: • Part I: Water Distribution • Part II: Air Entrainment • Part III: Full-Scale Residential Fire Experiments This report details the results and analysis from the air entrainment testing. These tests were conducted without the presence of fire to gain a fundamental understanding of how hose streams entrain air. Each set of experiments was intended to add to the understanding of air entrainment and pressure from fire service hose streams by evaluating the differences caused by various application methods, hose stream types, nozzle movements, pressures/flow rates, manufacturers, and ventilation configurations.