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2.
A new evacuation method for emergencies, the Follow Me method, in which each leader takes only one evacuee to an exit without gesturing or loudly directing many evacuees toward the exit, was compared, in two field experiments, with a traditional method, the Follow Directions method, in which each leader indicates the direction with a loud voice and vigorous gestures. Results showed that the Follow Me method was more effective when the leader-to-evacuee ratio was relatively small, such as 1:4, and less effective when the ratio was large, such as 1:8. Effective evacuation by the Follow Me method was shown to be caused by the drawing power of emergent small groups. Generating from around a leader, other evacuees rapidly formed a collective stream toward the exit. Small groups can be used as a lever in moving a larger collectivity in an emergency, as well as in activating a large formal organization. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
3.
The electron-microscopic visualization of acrylic rubber dispersed in a heterogeneous structural resin composition consisting of a rubber-modified two-phase plastic comprising essentially a butyl acrylate rubber phase and an acrylonitrile–styrene copolymer phase, respectively, has been accomplished. This procedure consists of the following: The molded resin specimen is treated with hydrazine hydrate solution to produce the acrylic acid hydrazides. Allow the treated specimen to soak in osmium tetroxide solution. The acrylic rubber may be indirectly fixed and stained. Some micrographs of ultrathin sections of two or three resin compositions, cut by an ultramicrotome, are presented. 相似文献
4.
Yoshiro Funakoshi Masaki Yamamoto Yoshihiko Matsumura Hiromu Komeda 《Powder Technology》1980,27(1):13-21
Necessary conditions were studied for the optimum operation of agglomeration granulation. The mechanisms that would realize these conditions were investigated by several experiments.On the basis of the results obtained, a novel granulating system involving a surface wetness control mechanism has been developed.The present paper describes the mixing and dispersing characteristics of the coating vessel, the detection method for wetness control, the particular spraying units, and the operating conditions thereof, together with the characteristics of this newly developed powder coating granulation system.This system has been shown to provide an easy and reproducible granulating technique even when products below 1 mm in size are required. 相似文献
5.
Catalytic performances of various metal molybdates were tested in the oxidative dehydrogenation of propane to propene with molecular oxygen under an atmospheric pressure. Most of the molybdates tested promoted the selective oxidative conversion of propane to propene and among them cobalt and magnesium molybdates were found highest in the activity and selectivity. It was also found that their catalytic activities were highly sensitive to the catalyst composition, and it turned out that Co0.95MoO
x
and Mg0.95MoO
x
catalysts which have slightly excess molybdenum showed the highest activity in the oxidative dehydrogenation of propane. Under the optimized reaction conditions, higher reaction temperatures and lower partial pressures of oxygen, these catalysts gave 60% selectivity to propene at 20% conversion of propane. Since the molybdates having the surface enriched with molybdenum oxide tended to show high activity for the propane oxidation, surface molybdenum oxide clusters supported on metal molybdate matrix seem to be the active sites for the selective oxidative dehydrogenation of propane. 相似文献
6.
Yoshihiko Sadaoka Enrico Traversa Masatomi Sakamoto 《Journal of Alloys and Compounds》1996,240(1-2):51-59
Perovskite-type LaxLn1−x″CoO3 oxides are prepared by the thermal decomposition of LaxLn1−x″ [Co(CN)6] · nH2O hetero-nuclear complexes. Except for LaCoO3 (hexagonal), the structures observed for LaxSm1−xCoO3 are othorhombic. While the perovskite-type oxide HoCoO3 is not formed by decomposition at 1000°C of the corresponding hexacyano complex, the partial replacing of Ho with La is effective in forming the pervoskite-type oxide having an orthorhombic structure containing Ho even at 800°C. A monotonous correlation (quasi-linear relationship) was found between the b- and c-lattice constants of the orthorhombic structures of the perovskite-type oxides and the effective radii of Ln ions, defined as reff = xr1.a + (1 − x)r1.0″. The distortion parameter for the orthorhombie cell (3″a/b−1) increaseswith decrease in reff and is expected to be 0.270 for perovskite-type HoCoO3. The crystal structure of the LaxLn1−x″, CoO3 oxides is mainly controlled by the effective radii of Ln ions. 相似文献
7.
Database of human motion has been widely used for recognizing human motion and synthesizing humanoid motions. In this paper,
we propose a data structure for storing and extracting human motion data and demonstrate that the database can be applied
to the recognition and motion synthesis problems in robotics. We develop an efficient method for building a human motion database
from a collection of continuous, multi-dimensional motion clips. The database consists of a binary tree representing the hierarchical
clustering of the states observed in the motion clips, as well as node transition graphs representing the possible transitions
among the nodes in the binary tree. Using databases constructed from real human motion data, we demonstrate that the proposed
data structure can be used for human motion recognition, state estimation and prediction, and robot motion planning. 相似文献
8.
In maintenance of concrete structures, crack detection is important for the inspection and diagnosis of concrete structures.
However, it is difficult to detect cracks automatically. In this paper, we propose a robust automatic crack-detection method
from noisy concrete surface images. The proposed method includes two preprocessing steps and two detection steps. The first
preprocessing step is a subtraction process using the median filter to remove slight variations like shadings from concrete
surface images; only an original image is used in the preprocessing. In the second preprocessing step, a multi-scale line
filter with the Hessian matrix is used both to emphasize cracks against blebs or stains and to adapt the width variation of
cracks. After the preprocessing, probabilistic relaxation is used to detect cracks coarsely and to prevent noises. It is unnecessary
to optimize any parameters in probabilistic relaxation. Finally, using the results from the relaxation process, a locally
adaptive thresholding is performed to detect cracks more finely. We evaluate robustness and accuracy of the proposed method
quantitatively using 60 actual noisy concrete surface images. 相似文献
9.
This note examines testing methods for Paretoness in the framework of rank-size rule regression. Rank-size rule regression describes a relationship found in the analysis of various topics such as city population, words in texts, scale of companies and so on. In terms of city population, it is basically an empirical rule that log?(S(i)) is approximately a linear function of log?(i) where S(i) is the number of population of i th largest city in a country. This is closely related to the so-called Zipf’s law. It is known that this kind of empirical observation is found when the city population is a random variable following a Pareto distribution. Thus one may be willing to test if city size has a Pareto distribution or not. Rosen and Resnick [K.T. Rosen, M. Resnick, The size distribution of cities: an explanation of the Pareto law and primacy, Journal of Urban Economics 8 (1980), 165–186] and Soo [K.T. Soo, Zipf’s law for cities: a cross country investigation, Regional Science and Urban Economics (35) 2005, 239–263] regress log?(S(i)) on log?(i) and log?2(i) and test the null of Paretoness by standard t-test for the latter regressor. It is found that t-statistics take large values and the Paretoness is rejected in many countries. We study the statistical properties of the t-statistic and show that it explodes asymptotically, in fact, by simulation and thus the t-test does not provide a reasonable testing procedure. We propose an alternative test statistic which seems to be asymptotically normally distributed. We also propose a test with the null hypothesis that the city size distribution is Pareto with exponent unity, which is a modification of the F-test. 相似文献
10.
Yasushi Hosokawa Daiki Urata Akio Doi Toyoo Takata Yoshihiko Abe 《Artificial Life and Robotics》2017,22(3):346-356
The virtual diving experience learning system of “Ama”, Japanese traditional female divers, has been developed to simulate how divers move in a virtual space using the diving interface and utilizing an accelerometer and a gyroscope. This interface not only detects the diving motion but also outputs the movement. Diving motion is shown in the ways of hand motion while standing. Although this makes it possible for a learner to understand the divers’ actions more clearly, this system’s difficulty is in visualizing a divers’ actions including their hands or bodies. Therefore, our study focuses on developing the operation system to reproduce actual ways of Amas’ diving with a virtual human body in a virtual space. First, the motion capture was done in an underwater condition. In the next process, the virtual human body was created. Finally, with the motion viewer, the more vivid actions of the Ama were successfully reproduced much more than in previous attempts. Using this system, the effectiveness of the Amas’ movement learning was confirmed, because a learner practices Amas’ movement. 相似文献