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In fire evacuation situations, at corridors, many evacuees are plagued by high density, low velocity, and long waiting time. Therefore, engineers have to consider the countermeasure preventing crowd accidents. For this purpose, the development of pedestrian simulators that are constructed with concrete physical parameters, such as the headway distance between pedestrians, velocity, and specific flow, is required. To acquire the evacuation behavior in corridors, we conducted well-controlled pedestrian walking experiments in a confined corridor with realistic architectural geometry and modeled the pedestrian behaviors. An experimental loop corridor was constructed to acquire stable pedestrian flows without distractions from bottlenecks or merging flows. We conducted five experiments with different density patterns with an average density ranging from 1.28 to 3.42 people/m2 and a maximum of 96 test participants. We found that when the headway distance is 0.55–1.15 m, the velocity increases linearly with increasing headway distance, similar to single-file experiments. When the density is higher than 2.35 people/m2, the pedestrians cannot walk at a constant speed, and they exhibit stop-and-go behavior. In this situation, the percentage of pedestrians who walk at a headway distance of approximately 0.4–0.5 m, which is the minimum headway distance, increases. In addition, the fundamental diagram between density and velocity is acquired at a density higher than 1.4 people/m2 as an inversely proportional function. The density dependence on the specific flow is a linear function. The maximum specific flow is acquired at the marginal minimum density where a linear relationship is maintained.

SimTread was developed as a pedestrian simulation system following a straightforward, highly user‐definable pedestrian and spatial model. Unlike network and mesh models, this pedestrian model is a multi‐agent system in which an individual pedestrian is modeled as an agent. The spatial model is based on actual coordinates, which enables the direct representation of plans using the SimTread model. The crowd characteristics represented by this system were evaluated through test cases by measuring the flow rate, which is a primary indicator of crowd evaluation. The major results are as follows: (a) SimTread demonstrated a reasonable crowd‐behavior simulation in a simple plan that was equivalent to network models. Along with the added benefits of operability, such performance is highly desirable. (b) In cases where a bottleneck accumulated a number of pedestrians sufficient to block nearby exits, SimTread accurately portrayed the resulting crowd propagation. This allowed qualitative crowd analysis.

Cancer can develop into a recurrent metastatic disease with latency periods of years to decades. Dormant cancer cells, which represent a major cause of recurrent cancer, are relatively insensitive to most chemotherapeutic drugs and radiation. We previously demonstrated that cancer cells exhibited dormancy in a cell density-dependent manner. Dormant cancer cells exhibited increased porphyrin metabolism and sensitivity to 5-aminolevulinic acid-based photodynamic therapy (ALA-PDT). However, the metabolic changes in dormant cancer cells or the factors that enhance porphyrin metabolism have not been fully clarified. In this study, we revealed that lipid metabolism was increased in dormant cancer cells, leading to ALA-PDT sensitivity. We performed microarray analysis in non-dormant and dormant cancer cells and revealed that lipid metabolism was remarkably enhanced in dormant cancer cells. In addition, triacsin C, a potent inhibitor of acyl-CoA synthetases (ACSs), reduced protoporphyrin IX (PpIX) accumulation and decreased ALA-PDT sensitivity. We demonstrated that lipid metabolism including ACS expression was positively associated with PpIX accumulation. This research suggested that the enhancement of lipid metabolism in cancer cells induces PpIX accumulation and ALA-PDT sensitivity.

In this study, pedestrian crowd dynamics at corner turns were investigated by analyzing pedestrian trajectories in a subject experiment for building more reliable, general-purpose, pedestrian simulation models. An experiment under laboratory conditions was conducted wherein a pedestrian crowd walked straight for a short distance before turning into a right-angled corner built with partition walls; the opposite sides were unwalled. Trials were performed with different widths and densities of initial participant positions. Finally, the trajectories of the pedestrians were extracted from a video through computer image analysis. The results demonstrated that pedestrian behavior at corner turns depends on lane position, lane distance (from the wall), and crowd density.

The occupants shall evacuate the building through stairs, in case of fire of high-rise building. A number of evacuees may cause the congestion on stairs. This paper focuses on the characteristics of the non-merging evacuation flow, which is the flow consisting only of evacuees descending on the staircase without merging there under flow conditions on the upper floor, which are generated by the merging of persons going down the staircase and entering there. This study used the data obtained in the observational survey on the real evacuation drills repeated annually for three years in the high-rise building. The flow conditions were classified into three groups based on the congestion and the merging of evacuations in the staircase. As a result of this study, the characteristics of the non-merging evacuation flow in each of the three groups were elucidated.

In amendment of Building Standards Act of the year 2000, the verification method for evacuation safety was introduced. Knowledge gained in Togawa’s study (1955) is frequently used in this verification method; however, depending on the spatial condition, the estimated results differ from the actual crowd walk nature and this remains a challenge. Considering the situation, this study aims to illustrate the relationship between the spatial condition and crowd walk nature and analyze data gained from the Crowd Evacuation Experiment done in 2015 at Tokyo University of Science. When a corridor includes an opening (a bottleneck) or a merging, a pedestrian crowd will be restrained at the opening/merging. Each part of the bottleneck corridor showed a very similar feature as the merging corridor. Therefore, this study analyzed the bottleneck corridor and merging corridor with a uniform model. These analysis results confirmed the relationship between each part’s density and the ratio of inflow width to the outflow width and showed that specific flow can be calculated from the margin of two densities, regardless of the spatial condition.

In 2017 in Tokyo, more than thousand occupants of a seven-story office building evacuated due to fire located at an adjacent site. Because the fire did not occur on their own site, the evacuation was spontaneous and, therefore, not performed according to a normal evacuation manual. This paper investigates the human behavior in this evacuation case, especially focusing on the decision-making process. To do this, the authors conducted face-to-face interviews with four people from the organization who made the decision to let employees evacuate and forty-one employees who evacuated. The major findings of the study are: (1) visual observation of fire through windows influences the occupants’ evacuation strategy; (2) occupants tended to postpone leaving the workplace until they received an explicit evacuation cue from others; and (3) multiple occupants chose stairs by taking into consideration that the fire was not in their building. Since the fire compartments had not yet been built and there was no immediate danger to life, these results can also be applied to the evacuation of non-fire floors in a building fire.

This study analysed evacuees’ movements in three sequentially announced evacuation drills in a theatre to clarify evacuees’ route choice mechanism in an auditorium and to obtain a data-set for the validation of evacuation simulations and egress time calculations. The drills were conducted in a multi-purpose theatre in Japan over consecutive years, involving approximately 400 –540 occupants aged 6–90. The coordinates of every occupant in the auditorium during the drills were accurately obtained every 0.5 s using the authors’ original software programmes, so that evacuees’ trajectories and walking speeds at each point could be obtained. Thereby, we obtained more than 100,000 data points in total to analyse. The drills were also compared from the point of view of the flow control of the facility’s staff during the evacuation. The results revealed that, while the evacuees in the centre blocks chose the closest aisle from their seats, most of the evacuees in the side blocks chose the wall side aisles. The occupants did not create queues in aisles between seat blocks. They tended to walk along seatways, the narrow spaces between seat rows to get closer to their target exit, rather than stacking in the aisles. In addition, the specific flow at exit doors from the auditorium in a congested situation was ca. 0.96 pers./m/s.

Despite the total evacuation time of occupants in a multi-storey building not being affected by pedestrian merging on stairs, the calculation of evacuation times in each individual floor depends on the pedestrian merging ratio. In fact, different merging ratios may cause an evacuation to take place from the top to the bottom or vice versa. A simplified simulation model for the calculation of evacuation time at each floor is presented here. This model allows the investigation of the impact of two main variables affecting the evacuation time at each floor, namely 1) different initial numbers of pedestrians at each floor (i.e. occupant load), and 2) different merging ratios at each floor. This means that the model allows the calculation of the evacuation time at each floor considering a building with different occupancy types at different floors (e.g. office, residential, commercial, etc.) and different merging ratios which may be caused by a different configuration of the landing door at each floor. The model is presented in this paper using a case study of a hypothetical building. A detailed discussion on the model assumptions, advantages and limitations is also provided.

An increasing demand for electricity and preserving the environment has become a great driving force for the development of advanced boilers for coal-fired plants to improve their plant efficiency by raising the operating temperature. To achieve this purpose, the development of materials that possess a high mechanical strength and excellent resistance against corrosion at high temperatures is required. Considering such situation, the high-temperature corrosion behavior of SiO2-forming materials such as CrSi2-Ni and CoNiCrAlY-Si alloys in atmospheres containing NaCl and Na2SO4 is introduced. The SiO2 scale plays a significant role in suppressing the inward diffusion of sulfur and chlorine, resulting in the remarkable suppression of the formation of sulfide and chloride at the scale/substrate interface and inside of the substrate. Based on such results, it is emphasized that SiO2-forming materials show outstanding corrosion resistance against atmospheres containing NaCl and Na2SO4.

The type and relative position of evacuation signage to evacuees’ location can affect their likelihood to understand and comply with the information provided. To address this issue, a Virtual reality (VR) experiment with 60 participants was carried out to investigate the effect of signage vs viewer placement on the compliance with the indicated direction in case of evacuation. The VR experiments were conducted with a head mounted display. Different independent variables linked to the signage placement/type were investigated in a VR underground square scenario, namely (1) the installation position (i.e., distance, angle of interaction), and (2) the arrow type in use on the signage. Participants selected evacuation routes in VR and a questionnaire investigating their degree of confidence regarding their choice was performed. Results show that the angle of interaction affects the evacuees’ chosen direction. Participants showed a higher degree of confidence when the arrow pointed towards the centre of the route. In addition, after a distance of 2.0 m from the centre, the correct answer rate of the evacuation signage for the cases of arrows pointing left, right and up become comparable. The use of an up arrow performed as well as the use of left and right arrows, while an arrow pointing down was not as clearly understood. The concept of visible area ratio is suggested to evaluate the compliance with the direction indicated by evacuation signage. The result is supported by the relationship between the lateral position of the signage and the calculated angle of interaction.

Pedestrian merging flows on stairs are defined as the confluence of a flow of pedestrians from a stair and pedestrians from each floor of a multi-storey building. This paper introduces a novel simplified mathematical model for the calculation of evacuation times on stairs which takes into account the impact of merging flows. The model allows calculating the impact of merging ratio (people accessing the stair landing from the floor and from the stair) on pedestrian flows and evacuation times at each floor in congested situations. The assumptions and implementation of the model are presented. A hypothetical model case study of a 10-floor building evacuation is investigated, where the results of the new model are compared with the results of an evacuation simulation model using SimTread. Advantages and limitations of the new model in relation to the existing methods adopted for the simulation of merging flows on stairs are discussed.

Evacuees within fire-affected buildings may have to escape through smoke-filled corridors without the aid of lighting, with a high probability of failing to escape. It is thus of vital importance to enhance evacuation safety procedures. It is equally necessary to study changes in walking speeds in situations of fire escapes in order to accurately estimate time required to escape. This paper focuses on measuring changes in walking speeds of evacuees, as influenced by emergency signs, smoke, and illumination. Participants, 20 non-disabled individuals with normal vision, were made to individually traverse a corridor in which conditions were controlled, including the presence/absence of an emergency exit sign, smoke density, and ceiling lights. Changes in walking speeds under the three aforementioned conditions, including smoky or blackout conditions, were accurately measured and their influences on walking speeds were identified. The results will be useful to estimate evacuation time in situations of fires.

Scientifically validated tools to assess housing accessibility for older adults in Japan have been lacking. To address this, a rigorous procedure of adapting an existing housing assessment tool—the Housing Enabler, developed in Sweden—for valid use in Japan was conducted. The original tool was translated into the Japanese language, using established translation procedures. In the process, researchers checked the appropriateness of technical terms and adjusted specifications to be in accordance with Japanese standards. An expert panel approach was used to validate the content of the Japanese Housing Enabler. Thirteen certified occupational therapists, architects and care-managers (average experience=14.5 years) participated as experts in the content validity study. They rated each item with regard to relevance for assessing housing accessibility in Japan, on a scale from 1(=Not relevant) to 4(= Highly relevant). They suggested adjustments and additions that they found to be relevant to capture particularities of Japanese housing and building design. After individual ratings, the experts gathered for consensus discussions on suggested revisions of the item list. As a result, the number of items was substantially increased (from 161 to 283). A content validity index (CVI) was calculated for each item (i.e., the proportion of experts rating the relevance as at least 3). Using a recommended threshold of CVI ≥0.78, more than 90% of the items were considered relevant, thus supporting the content validity. However, the large amount of items might jeopardize the feasibility of the instrument. Further studies are needed to evaluate feasibility, criterion-related validity and aspects of reliability.

Summary Many studies have been conducted on the evacuation behavior on the staircases of buildings, but very little data are available for a situation with many occupants in a crowded high-rise building. Therefore, this study investigated the evacuation behavior of a large number of evacuees on the staircase of a 25-story high-rise building. A total evacuation drill was conducted with 2088 evacuees, and the behavior of 1136 evacuees on the landings of the south staircase was recorded by a video recorder on the ceiling. The relationship between the density and speed of the evacuees on the landings was analyzed from the evacuation data for two situations: without and with merging in the stair flow. The evacuation stair flow in this drill had merging occupants entering from the floors, but no one entered from the lower floors during the latter period of the drill. Therefore, the flow during the latter period was treated as non-merging flow, for which it was observed that, when the staircase was fully crowded, the density on the landings in the moving situation was different from that in the stopped situation. Moreover, the density on the landings was different from that on the treads. Furthermore, in the merging flow, a merging ratio of approximately 50:50 occurred during the congested evacuation. Copyright © 2016 John Wiley & Sons, Ltd.

This study investigates the factors that effect of human body shape on the pedestrian's specific flow rate at openings. The results of the authors' experiment show that the mean pedestrian specific flow rates were appendix more than 2.0 person/m/s. Furthermore, the flow late increases with the opening width not linearly but in form of a step function. The participants often twisted their shoulder when they entered to the opening in particular if they passed near the opening edge through. This action makes their projected body width against the opening smaller so that they could enter into spatial gaps that were smaller than their actual body width.

Tsunami evacuation plans have been deliberately developed by local governments in coastal areas in Japan under guidance from the national government since before the Great East Japan Earthquake in March 2011. These plans, however, do not mention the time required for all local residents to evacuate to evacuation areas. This paper reports a procedure to design an effective tsunami safe town planning using multi-agent simulator (MAS) which identify a degree of evacuation risk in objective area. A case study is applied to one of the worst hit town of tsunami, in which additional facilities such as evacuation areas, safe buildings, and evacuation routes are proposed as well.

Ticket gates in railway stations or stadiums and security gates in office buildings pose difficulties for evacuation in in case of fire. This paper focuses on the characteristics of a crowd passing through the ticket gates of Japanese railway stations. The characteristics of a crowd flow passing through ticket gates were identified, and numerical values were derived to estimate the evacuation time. A total of 48 subjects were asked to pass through a ticket gate with three passages and three different wide passages, where each width was the same as the sum of the three passage widths of the ticket gate. The crowd flow through the ticket gate was simulated with the pedestrian simulation model SimTread. The results of this study elucidated the flow rate through the ticket gates and the numerical values to calculate the time for evacuation planning.