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The present paper is designed to provide a summary of our study on the high temperature corrosion of Al2O3, SiO2 and Al2O3–SiO2 forming alloys in the gas phase and liquid phase of Na2SO4–NaCl system by comparing their corrosion resistance at 1000 °C. The obtained results show that the alumina-forming alloy experiences severe internal corrosion in the gas phase compared to in the liquid phase due to oxide cracking. This results in an increase in the inward diffusion and/or penetration of constituents of the salts and oxygen to form internal Al-oxide and Cr-sulfides. In the liquid phase, however, the formation of yttrium sulfide beneath a continuous double oxides layer of Al5Y3O12 and Al2O3 may be related to the high affinity of yttrium for sulfur. On the other hand, it is apparent from the cross-sectional observations that a SiO2 and Al2O3–SiO2 forming alloys form a continuous and dense oxides layer, and demonstrate a high resistance against internal oxidation and corrosion in both corrosive environments.

The high temperature corrosion behavior of Si-containing alloys consisting of Cr-Si-Ni and CoNiCrAlY-Si alloys fabricated by spark plasma sintering technique was investigated in the liquid phase of Na2SO4 + 25.7 mass% NaCl at temperatures ranging from 923-1273 K. The purpose of this study is to develop excellent corrosion resistant alloys for coating applications. Our experimental results show the CrSi2 alloy with 10 mass% Ni content and the CoNiCrAlY alloy with 30 mass% Si content are the most promising materials for applications in this atmosphere. This is due to the formation of a protective SiO2 and Al2O3/SiO2 scale, respectively. The formation of a dense and continuous oxide layer composed and/or consisted of SiO2 plays a significant role in hindering the inward diffusion of chlorine and sulfur to the alloys substrate. Particularly, the corrosion mechanism of Cr-Si-Ni alloys and the influence of Ni addition on the corrosion resistance of CrSi2 alloy are discussed in the present paper.

The objective of this study is to develop an excellent corrosion resistant alloy for high temperature coating applications. The Si-containing alloys consisting of CoNiCrAlY and CrSi2 alloys with varying Si and Ni content respectively were prepared by spark plasma sintering (SPS) technique. The corrosion behavior of these alloys was investigated in the gas phase of air-(Na2SO4+25.7mass%NaCl) at elevated temperatures of 923, 1073 and 1273K. The results showed that CoNiCrAlY alloy with 30mass% Si content and CrSi2 alloy with 10mass% Ni content were the most effective materials for application in the gas phase of air-(Na2SO4+25.7mass%NaCl) due to the formation of protective Al2O3/SiO2 and SiO2 scale, respectively. Therefore, it is realized that CoNiCrAlY-30mass% Si and CrSi2-10mass% Si coating are very effective for improving of high temperature corrosion resistance of STBA21 steel.

The addition of Si to CoNiCrAlY was considered in order to develop corrosion resistant alloys for coating applications. The high temperature corrosion behavior of spark plasma sintered CoNiCrAlY alloys of 0, 10, 20, and 30 mass% Si content was investigated in an air-(Na2SO4+25.7 mass%NaCl) gas atmosphere at elevated temperatures of 923, 1073, and 1273 K. The results showed that CoNiCrAlY-Si alloys formed mainly an Al2O3 or Al2O3/SiO2 scale, depending on the alloy composition and the temperature. The addition of 30 mass% Si significantly improved the high-temperature corrosion resistance of CoNiCrAlY alloy in an air-(Na2SO4+25.7 mass%NaCl) gas atmosphere at these temperatures. The high temperature corrosion behavior of CoNiCrAlY-Si alloys was discussed in the present paper.

In the near future, there will be several types of the leading robots that lead us a way to a destination in our daily life spaces. Some experiments were conducted in order to clarify the characters behaviors of human in follow-walking after leading robots in a real corridor. Following results were obtained. 1) The distance to the robots were kept in from 900 to 1100(mm). And 2) Subjects tended to gaze at the short size robot (300mm height) more frequently than the middle size one (600mm height). 3) When the leading speed is lower (0.34m/s), subjects tended to gaze at the short size robot (300mm height) more frequently than the tall size one (900mm height). 4) The characteristic fixation pattern was found that was gazing at the midair area above the head of the robots.

SimTread has been developed as a pedestrian simulation system with straightforward pedestrian and space model, which is highly operable by the users. The pedestrian model is a multi agent system in which the individual pedestrian is modeled as agents, and the space model is based on real coordinates, on the contrary of network and mesh models, that enable to represent plans directly into models.The characteristics of crowd represented in this system had been evaluated through test cases by measuring the flow rate that is a major index for evaluating crowd.Major results are as follows 1. In a simple plan that are comparable to network models, SimTread showed reasonable behaviours of crowds, which in terms of operability, can be concluded as highly desirable performance. 2. In a case where a bottleneck accumulates enough pedestrians so that consecutive exits will be virtually closed, SimTread showed accurately the propagation of crowd, which led to qualitative analysis of the crowd.

In view of the rapid large scale development of underground in the central big cities, especially around terminal stations, evacuation experiments have been conducted with 79 subjects using an underground shopping mall near Tokyo Station actually in service after business hours. Four groups of 20 subjects started from different locations and time to “escape” from any of emergency exits was measured for each subject. 12 out of the 79 subjects wore elderly simulator to compare evacuation behavior of elderly and that of younger people. The evacuation behavior was also monitored by video cameras and escape route of each subject was reproduced afterwards. Five experiments were conducted using the lighting conditions and layout of emergency exits as parameters. The starting point was changed from experiment to experiment, not making any subject repeat similar selection of escape route. The shopping mall is composed of grid of passages, and is installed with escape route sign lights on every passage according to Fire Service Law. In every experiment, it was observed that considerable portion of subjects did not select right passage toward nearest exit at intersection nor passed over right exits. These are not compliant with widely accepted assumption for deterministic modeling of evacuation in mall-like facility. Factors dictating the probability to select right passage at intersections and that to recognize emergency exit are analyzed from the experimental data.

The purpose of this study was to investigate the effects of merges on crowds in a staircase and the ease of merging with variations in crowd density, directions of merge, and whether the door joining a hallway to a staircase was opened or closed. The results led to the following conclusions: 1) merging is easier at lower population density; 2) merging is easier if the direction of the merging crowd is same as the direction of the crowd in the staircase; and 3) merging is easier if the door is initially opened, and the evacuation speed is decreased by 30% when the door is initially closed.

The purpose of the study is to investigate the criterion for the force required to open fire doors, and the required dimensions of fire door frames, from an ergonomic point of view for wheelchair users, through conducting experimental studies on passing through fire doors.This study implemented two types of experimental design, observing subjects passing through fire doors, and measuring the force required to open them.The results of the study show that it is desirable for fire doors to have a required opening force of no more than 40N and a width of more than 850mm. When using a wheelchair, the direction from which the door is approached has a significant impact on whether or not the subject can pass through the door. From these observations, it is postulated that in cases where corridors are narrow and there is not sufficient room to maneuver a wheelchair, a wheelchair user will often be unable to evacuate safely to the stairwell if they approach the fire door from the door knob side. Therefore it is essential that there is sufficient space in front of the fire door to bring a wheelchair parallel to the door, and also to rotate the wheelchair 180 degrees when necessary.

The purpose of this study is to analyze the patterns of complicated pedestrian flow with visible pedestrian area model. The coordinates of all pedestrians at each frame is calculated.The pedestrian area is defined as the 90cm circle from the coordinates of each pedestrian. The condition of monodirectional pedestrians which forms groups is similar to the distribution of electric field, so Blobs, Meta-ball, with Bezier Clipping method is used to visualize the pedestrian area. (1) The conflict among pedestrians is reduced by the forming group of monodirectional pedestrians; (2) The pedestrian move along the edge of other group's area because he/she can't cross inside the group; (3) The overlap of group's area illustrates the conflict between groups;The condition of pedestrian flow is analyzed with visible pedestrian area model.

The purpose of this study is to evaluate the pedestrian space with time series interfering area model. The model illustrates the interference of pedestrian's area in the several directions. And the coordinates of pedestrians are sensed and used for evaluation of the space. The “time series interfering area model” describes the load between pedestrians in the several directions. This model's advantage is as follows; (1) The characteristics of pedestrian loads in a time series are grasped and comprehended with it. (2) As the congestion in the observation area in a time series is observed, and the area is evaluated particularly. (3) The situations of intersecting pedestrians in the several directions are grasped.

This paper describes the characteristics of crowd flow passing through simple-shaped rooms and to validate an evacuation simulation model called “SimTread”. It presents experiments on crowd flow with 43 subjects and intends to quantify the aspects of crowd flow in simple rooms. Recently, for estimating evacuation of buildings on fire, several computer simulation models have been developed and applied. However, human evacuation data-sets for validating simulation are scarce. The results of this study show that pedestrian flow rate at the opening changes depending on the density of the space connected. Flow rate rises if the opening is connected to larger space, which is less dense and, in result, increases speed of pedestrians. For validating an evacuation simulator, evacuation data from actual building fires are too complex for proving the equivalence. Therefore, we carried out the experiments of crowed flow passing through simpleshaped rooms, and compared experimental data with our simulation results. There was a good agreement between the result of experiments and simulations. The differences were less than 10%.

Conference on Pedestrian and Evacuation Dynamics, PED 2014, Delft, Netherlands, 22 Oct 2014 - 24 Oct 2014; Transportation Research Procedia 2, 367-375 (2014). doi:10.1016/j.trpro.2014.09.034 special issue: "Conference on Pedestrian and Evacuation Dynamics : (PED 2014) ; Delft, The Netherlands, 22 - 24 October 2014 / ed.: Winnie Daamen, ...", Published by Elsevier, Amsterdam [u.a.]

This paper presents the characteristics of pedestrian movement around doors connected to corridors. We focused on the flow rates through a door connected to a corridor to verify the evacuation safety for a performance-based design. In full scale evacuation experiment, when the corridor connected to a door was crowded, the flow rate at the door decreased. Furthermore, the differences between the experimental results and those from multi-agent pedestrian simulator were investigated to examine the validity of the simulation.