Characteristics of merging behavior in large crowds

2022 ◽  
Vol 2022 (1) ◽  
pp. 013403
Author(s):  
Liping Lian ◽  
Xu Mai ◽  
Weiguo Song ◽  
Jun Zhang ◽  
Kwok Kit Richard Yuen ◽  
...  
Keyword(s):  
Shannon Entropy ◽  
Safety Management ◽  
Main Channel ◽  
Pedestrian Flow ◽  
Controlled Experiments ◽  
Public Infrastructure ◽  
Laboratory Conditions ◽  
Merging Behavior ◽  
Relationship Of ◽  
The Relationship

Abstract Merging pedestrian flow can be observed often at public intersections and locations where two or more channels merge. Because of restrictions on the flow, pedestrian congestion, or even crowd disasters (e.g. Hajj crush 2015) happen easily at these junctions. However, studies on merging behaviors in large crowds remain rare. This paper investigates the merging characteristics of the pedestrian flow with controlled experiments under laboratory conditions. The formation of lanes is observed, and the lane separation width can vary for different density levels. Shannon entropy is used to analyze the utilization of the passage. The space usage in the merging area is most efficient when the width of the two branches is half that of the main corridor. Furthermore, the branch and main channel can mutually bottleneck each other in the large crowds and the flowrates for the upstream, downstream and branches are investigated. This study uses spatiotemporal diagrams to explore the clogging propagation of the merging flow as well as the relationship of the velocity and position. The results can be used as references for the design of public infrastructure and human safety management.

scholarly journals A Note on the Relationship of the Shannon Entropy Procedure and the Jensen–Shannon Divergence in Cognitive Diagnostic Computerized Adaptive Testing

SAGE Open ◽  
2020 ◽  
Vol 10 (1) ◽  
pp. 215824401989904
Author(s):  
Wenyi Wang ◽  
Lihong Song ◽  
Teng Wang ◽  
Peng Gao ◽  
Jian Xiong
Keyword(s):  
Shannon Entropy ◽  
Selection Criteria ◽  
Computerized Adaptive Testing ◽  
Adaptive Testing ◽  
Item Selection ◽  
Item Parameters ◽  
Post Hoc ◽  
Relationship Of ◽  
Jensen Shannon Divergence ◽  
The Relationship

The purpose of this study is to investigate the relationship between the Shannon entropy procedure and the Jensen–Shannon divergence (JSD) that are used as item selection criteria in cognitive diagnostic computerized adaptive testing (CD-CAT). Because the JSD itself is defined by the Shannon entropy, we apply the well-known relationship between the JSD and Shannon entropy to establish a relationship between the item selection criteria that are based on these two measures. To understand the relationship between these two item selection criteria better, an alternative way is also provided. Theoretical derivations and empirical examples have shown that the Shannon entropy procedure and the JSD in CD-CAT have a linear relation under cognitive diagnostic models. Consistent with our theoretical conclusions, simulation results have shown that two item selection criteria behaved quite similarly in terms of attribute-level and pattern recovery rates under all conditions and they selected the same set of items for each examinee from an item bank with item parameters drawn from a uniform distribution U(0.1, 0.3) under post hoc simulations. We provide some suggestions for future studies and a discussion of relationship between the modified posterior-weighted Kullback–Leibler index and the G-DINA (generalized deterministic inputs, noisy “and” gate) discrimination index.

EFFECT OF CHANGES IN ENVIRONMENT AND MANAGEMENT ON GROWTH OF PASTURE SPECIES

1954 ◽  
pp. 75-81
Author(s):  
K.J. Mitchell
Keyword(s):  
Light Intensity ◽  
Growth Characteristic ◽  
Leaf Tissue ◽  
Laboratory Conditions ◽  
Relationship Of ◽  
The Relationship

In considering the relationship of light and temperature to the growth of grasses and clovers it is important to know the actual conditions around individual plants in a pasture. Without that information the resuits of detailed experiments in glasshouse or laboratory conditions cannot be interpreted. For light intensity little comment is needed. It is well known that considerable shading occurs within a long pasture. Shorter plants are overshadowed by tall ones, but even for those taller plants a large proportion of their leaf tissue can be in dense shade. Consequently they will also assume a pattern of growth characteristic of shaded plants.

Use of Electrical Currents to Delay Intravascular Thrombosis in Experimental Animals

1956 ◽  
Vol 187 (3) ◽  
pp. 473-478 ◽  
Author(s):  
Philip N. Sawyer ◽  
Bernhard Deutch
Keyword(s):  
Controlled Experiments ◽  
Electrical Currents ◽  
Experimental Animals ◽  
Canine Experiments ◽  
Intravascular Thrombosis ◽  
Relationship Of ◽  
The Relationship ◽  
A Current

Previous studies on the relationship of electric phenomena to intravascular thrombosis have been discussed. On the basis of these studies, canine experiments were designed to determine whether or not a negatively charged electrode could by means of its oriented current prevent formation of a thrombus in an injured vessel. Using electrodes of several types a series of controlled experiments were performed which demonstrate that a current created by the technique used would delay intravascular thrombosis for periods up to 12 hours.

scholarly journals Toward an Infrastructural Sublime: Narrating Interdependency in Karen Tei Yamashita’s Los Angeles

MELUS ◽  
2020 ◽  
Vol 45 (2) ◽  
pp. 1-24
Author(s):  
Jina B Kim
Keyword(s):  
Los Angeles ◽  
American Literature ◽  
Public Infrastructure ◽  
Aesthetic Value ◽  
The Public ◽  
Self Sufficiency ◽  
Distribution Of Resources ◽  
Labor Networks ◽  
Relationship Of ◽  
The Relationship

Abstract This article examines the vibrant city infrastructures of Karen Tei Yamashita's 1997 novel Tropic of Orange in order to highlight interdependency as political and aesthetic value. The novel's emphasis on urban support systems—the oft-unnoticed roads, pipes, wires, and labor networks that allow the city to function—positions infrastructure as itself a critical lens, one that can reassess the relationship of ethnic American literature and subjectivity to the values of self-ownership, protest, and independence. By amplifying the overlooked support networks that underpin fictions of self-sufficiency, Yamashita's Tropic of Orange diverges from the narrative of self-ownership as liberatory endpoint. Instead, it recuperates the much-maligned category of dependency, positioning dependency as a vital site of aesthetic and political possibility within anti-racist and anti-capitalist struggle. This recuperation proves particularly significant in light of pernicious and persistent dependency mythologies, such as the “illegal immigrant,” that frame racialized subjects as drains on the public. Infrastructure, as an often unseen entity nonetheless central to the operation of cities and the global distribution of resources, represents a key vehicle in Tropic of Orange for thinking about contemporary ecologies of assistance, power, and provision, and for mapping the global imbalances of power that render certain dependencies hypervisible while erasing others.

scholarly journals Diet and reproduction of the fish Joturus pichardi (Mugiliformes: Mugilidae) in the Pacuare River basin, Costa Rica

2019 ◽  
Vol 11 (3) ◽  
pp. 430-435
Author(s):  
Derick Herrera-Solano ◽  
Francisco S. Álvarez ◽  
Daniel Stange-Fernández ◽  
Jennifer Contreras-Picado
Keyword(s):  
Land Use ◽  
Costa Rica ◽  
River Basin ◽  
Main Channel ◽  
Forest Land ◽  
Migratory Species ◽  
Reproduction Period ◽  
Relationship Of ◽  
First Time ◽  
The Relationship

Introduction: Joturus pichardi is an important migratory species that inhabits the rivers of the Atlantic zone of Costa Rica and has been little studied. Objective: To describe the diet and reproduction of J. pichardi and its relationship with environmental factors in the Pacuare River basin. Methods: Sixteen sampling sites were selected along the main channel or Pacuare River. The samplings were performed from October 2015 to October 2016. The gonads, stomach, and intestines of seven individuals of J. pichardi were analyzed. The relationship of J. pichardi between the physicochemical variables of the water and the structure of the habitat was analyzed. Results: Twenty individuals were collected at an elevation of 225-235masl. The occurrence of J. pichardi was related to sites with higher river velocity, high values of dissolved oxygen, rock substrate and forest land use. All the individuals analyzed had visceral fat and endoparasites in the stomach. Bryophytes, ferns, macroinvertebrates, and detritus were identified as part of the diet of J. pichardi. According to the analysis of gonads in adults, the individuals were identified in the gonadal state types I, II and V. Conclusions: Our results suggest J. pichardi is an omnivorous species associated with sites with rocks, rapids, well-oxygenated waters, and forest land use. Also, the analysis of gonads coincides with the known reproduction period of the species. Finally, individuals of Neoechinorhynchus spp. are recorded for the first time in stomachs of J. pichardi in Costa Rica.

scholarly journals Изучение взаимосвязи главных напряжений при разрушении морского льда

2020 ◽  
Author(s):  
A.I. Mamontov ◽  
M.V. Kitaev ◽  
O.E. Surov ◽  
V.V. Novikov
Keyword(s):  
Experimental Data ◽  
Potential Energy ◽  
Sea Ice ◽  
Research Method ◽  
Lateral Compression ◽  
Natural Conditions ◽  
Special Equipment ◽  
Laboratory Conditions ◽  
Relationship Of ◽  
The Relationship

Статья посвящена исследованию прочности морского льда. Методом исследования является сброс треугольного индентора (треугольный стальной клин) на поверхность морского льда, предварительно очищенную от верхнего слоя. Для измерения давления, потенциальная энергия индентора до сброса вычисляется расчетным способом, а глубина отпечатка после падения измеряется экспериментально. Экспериментальные данные собирались в разные годы. Температура льда во время проведения экспериментов была различной. В 2018г температура льда была -5С. В 2019 году температура льда была -1С. Сброс индентора производился с разных высот. В результате эксперимента установлена взаимосвязь главных напряжений. При небольшом боковом сжатии льда, давление при котором лед разрушается существенно возрастает. Особенностью этой работы является то, что эксперимент проводился в естественных условиях в одной из бухт г.Владивостока на расстоянии 200 метров от береговой линии, сброс индентора производился на очищенный морской лед. Этот метод исследования проще, чем сжатие образцов льда в лабораторных условиях, так как в последнем случае требуется специальное оборудование и трудоемкая организация проведения опытов.The article is devoted to the study of the strength of sea ice. The research method is the discharge of a triangular indenter (triangular steel wedge) onto the surface of sea ice, previously cleaned from the upper layer. To measure the pressure, the potential energy of the indenter before discharge is calculated, and the imprint depth after falling is measured experimentally. Experimental data were collected in different years. The temperature of the ice during the experiments was different. In 2018, the ice temperature was -5 С. In 2019, the ice temperature was -1 C. The indenter was reset from different heights. As a result of the experiment, the relationship of the main stresses was established. With a small lateral compression of ice, the pressure at which the ice is destroyed increases significantly. A feature of this work is that the experiment was conducted under natural conditions in one of the bays of Vladivostok at a distance of 200 meters from the coastline, the indenter was discharged onto purified sea ice. This research method is simpler than compressing ice samples under laboratory conditions, since in the latter case special equipment and labor-intensive organization of experiments are required.

The relationship of the scleractinian corals to the rugose corals

Paleobiology ◽  
1980 ◽  
Vol 6 (02) ◽  
pp. 146-160 ◽  
Author(s):  
William A. Oliver
Keyword(s):  
Critical Points ◽  
Scleractinian Corals ◽  
Convincing Evidence ◽  
Early Triassic ◽  
Rugose Corals ◽  
History Of ◽  
The Subject ◽  
Relationship Of ◽  
The Relationship ◽  
Biologic Factors

The Mesozoic-Cenozoic coral Order Scleractinia has been suggested to have originated or evolved (1) by direct descent from the Paleozoic Order Rugosa or (2) by the development of a skeleton in members of one of the anemone groups that probably have existed throughout Phanerozoic time. In spite of much work on the subject, advocates of the direct descent hypothesis have failed to find convincing evidence of this relationship. Critical points are:(1) Rugosan septal insertion is serial; Scleractinian insertion is cyclic; no intermediate stages have been demonstrated. Apparent intermediates are Scleractinia having bilateral cyclic insertion or teratological Rugosa.(2) There is convincing evidence that the skeletons of many Rugosa were calcitic and none are known to be or to have been aragonitic. In contrast, the skeletons of all living Scleractinia are aragonitic and there is evidence that fossil Scleractinia were aragonitic also. The mineralogic difference is almost certainly due to intrinsic biologic factors.(3) No early Triassic corals of either group are known. This fact is not compelling (by itself) but is important in connection with points 1 and 2, because, given direct descent, both changes took place during this only stage in the history of the two groups in which there are no known corals.

Skeletal elements of crinoid echinoderms: High-resolution structural and microanalytical results

1983 ◽  
Vol 41 ◽  
pp. 194-195
Author(s):  
D. F. Blake ◽  
L. F. Allard ◽  
D. R. Peacor
Keyword(s):  
High Resolution ◽  
Marine Invertebrates ◽  
Sea Urchins ◽  
Structural Features ◽  
Sea Stars ◽  
High Resolution Tem ◽  
Relationship Of ◽  
The Relationship ◽  
Insight Into

Echinodermata is a phylum of marine invertebrates which has been extant since Cambrian time (c.a. 500 m.y. before the present). Modern examples of echinoderms include sea urchins, sea stars, and sea lilies (crinoids). The endoskeletons of echinoderms are composed of plates or ossicles (Fig. 1) which are with few exceptions, porous, single crystals of high-magnesian calcite. Despite their single crystal nature, fracture surfaces do not exhibit the near-perfect {10.4} cleavage characteristic of inorganic calcite. This paradoxical mix of biogenic and inorganic features has prompted much recent work on echinoderm skeletal crystallography. Furthermore, fossil echinoderm hard parts comprise a volumetrically significant portion of some marine limestones sequences. The ultrastructural and microchemical characterization of modern skeletal material should lend insight into: 1). The nature of the biogenic processes involved, for example, the relationship of Mg heterogeneity to morphological and structural features in modern echinoderm material, and 2). The nature of the diagenetic changes undergone by their ancient, fossilized counterparts. In this study, high resolution TEM (HRTEM), high voltage TEM (HVTEM), and STEM microanalysis are used to characterize tha ultrastructural and microchemical composition of skeletal elements of the modern crinoid Neocrinus blakei.

Studies on Leukemogenic and Sarcomagenic Viruses

1970 ◽  
Vol 28 ◽  
pp. 156-157
Author(s):  
Leon Dmochowski
Keyword(s):  
Electron Microscopy ◽  
Electron Microscope ◽  
Morphological Properties ◽  
Mode Of Development ◽  
Relationship Of ◽  
The Relationship

Electron microscopy has proved to be an invaluable discipline in studies on the relationship of viruses to the origin of leukemia, sarcoma, and other types of tumors in animals and man. The successful cell-free transmission of leukemia and sarcoma in mice, rats, hamsters, and cats, interpreted as due to a virus or viruses, was proved to be due to a virus on the basis of electron microscope studies. These studies demonstrated that all the types of neoplasia in animals of the species examined are produced by a virus of certain characteristic morphological properties similar, if not identical, in the mode of development in all types of neoplasia in animals, as shown in Fig. 1.

The relationship of IGE receptor topography to signaling activity in RBL-2H3 mast cells

1991 ◽  
Vol 49 ◽  
pp. 236-237
Author(s):  
J.R. Pfeiffer ◽  
J.C. Seagrave ◽  
C. Wofsy ◽  
J.M. Oliver
Keyword(s):  
Mast Cells ◽  
Protein A ◽  
Scattered Electron ◽  
Ige Receptor ◽  
Receptor Complexes ◽  
Ige Binding ◽  
Electron Imaging ◽  
Small Clusters ◽  
Relationship Of ◽  
The Relationship

In RBL-2H3 rat leukemic mast cells, crosslinking IgE-receptor complexes with anti-IgE antibody leads to degranulation. Receptor crosslinking also stimulates the redistribution of receptors on the cell surface, a process that can be observed by labeling the anti-IgE with 15 nm protein A-gold particles as described in Stump et al. (1989), followed by back-scattered electron imaging (BEI) in the scanning electron microscope. We report that anti-IgE binding stimulates the redistribution of IgE-receptor complexes at 37“C from a dispersed topography (singlets and doublets; S/D) to distributions dominated sequentially by short chains, small clusters and large aggregates of crosslinked receptors. These patterns can be observed (Figure 1), quantified (Figure 2) and analyzed statistically. Cells incubated with 1 μg/ml anti-IgE, a concentration that stimulates maximum net secretion, redistribute receptors as far as chains and small clusters during a 15 min incubation period. At 3 and 10 μg/ml anti-IgE, net secretion is reduced and the majority of receptors redistribute rapidly into clusters and large aggregates.

Sign in / Sign up

Export Citation Format

Share Document