Experimental evidences for bifurcation angles control on abandoned channel fill geometry

Abstract. The nature of abandoned channels sedimentary fills has a significant influence on the development and evolution of floodplains and ultimately on fluvial reservoir geometry. A control of bifurcation geometry (i.e., bifurcation angle) on channel abandonment dynamics and resulting channel fills, such as sandplug, has been intuited many times but never quantified. In this study we present a series of experiments focusing on bedload transport designed to test the conditions for channel abandonment by modifying the bifurcation angle between channels, the flow incidence angles and the differential channel bottom slopes. We find that disconnection is possible in the case of asymmetrical bifurcations with high diversion angle (≥ 30°) and quantify for the first time a relationship between diversion angle and sandplug length and volume. The resulting sandplug formation is initiated in the flow separation zone at the external bank of the mouth of the diverted channel. Sedimentation in this zone initiates a feedback loop leading to sandplug growth, discharge decrease and eventually to channel disconnection. Finally, the formation processes and final complex architecture of sandplugs are described, allowing for a better understanding of their geometry. Although our setup lacks the complexity of natural rivers, our results seem to apply at larger scales. Taken into account, these new data will improve the realism of fluvial models.

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Experimental evidence for bifurcation angles control on abandoned channel fill geometry

Earth Surface Dynamics ◽

10.5194/esurf-8-275-2020 ◽

2020 ◽

Vol 8 (2) ◽

pp. 275-288 ◽

Cited By ~ 1

Author(s):

Léo Szewczyk ◽

Jean-Louis Grimaud ◽

Isabelle Cojan

Keyword(s):

Bedload Transport ◽

Bifurcation Angle ◽

Fluvial Reservoir ◽

Abandoned Channel ◽

Reservoir Geometry ◽

Series Of Experiments ◽

Channel Bottom ◽

Abandoned Channels ◽

Complex Architecture ◽

Sand Plug

Abstract. The nature of abandoned channels' sedimentary fills has a significant influence on the development and evolution of floodplains and ultimately on fluvial reservoir geometry. A control of bifurcation geometry (i.e., bifurcation angle) on channel abandonment dynamics and resulting channel fills, such as sand plugs, has been intuited many times but never quantified. In this study, we present a series of experiments focusing on bedload transport designed to test the conditions for channel abandonment by modifying the bifurcation angle between channels, the flow incidence angles and the differential channel bottom slopes. We find that disconnection is possible in the case of asymmetrical bifurcations with high diversion angle (≥30∘) and quantify for the first time an inverse relationship between diversion angle and sand plug length and volume. The resulting sand plug formation is initiated in the flow separation zone at the external bank of the mouth of the diverted channel. Sedimentation in this zone induces a feedback loop leading to sand plug growth, discharge decrease and eventually to channel disconnection. Finally, the formation processes and final complex architecture of sand plugs are described, allowing for a better understanding of their geometry. Although our setup lacks some of the complexity of natural rivers, our results seem to apply at larger scales. Taken into account, these new data will improve fluvial (reservoir) models by incorporating more realistic topography and grain size description in abandoned channels.

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Thanato-Laboratorien. Theorien von Tod und Sterben und Elias Canettis Buch gegen den Tod

Kulturwissenschaftliche Zeitschrift ◽

10.2478/kwg-2019-0007 ◽

2020 ◽

Vol 4 (1) ◽

pp. 67-86

Author(s):

Elisabeth Heyne

Keyword(s):

Human Life ◽

Death And Dying ◽

Point Of View ◽

Visual Images ◽

Elias Canetti ◽

History Of ◽

Series Of Experiments ◽

First Time ◽

Textual Form ◽

Or History

AbstractAlthough visual culture of the 21th century increasingly focuses on representation of death and dying, contemporary discourses still lack a language of death adequate to the event shown by pictures and visual images from an outside point of view. Following this observation, this article suggests a re-reading of 20th century author Elias Canetti. His lifelong notes have been edited and published posthumously for the first time in 2014. Thanks to this edition Canetti's short texts and aphorisms can be focused as a textual laboratory in which he tries to model a language of death on experimental practices of natural sciences. The miniature series of experiments address the problem of death, not representable in discourses of cultural studies, system theory or history of knowledge, and in doing so, Canetti creates liminal texts at the margins of western concepts of (human) life, science and established textual form.

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The Instrumentally Derived Incentive-Motivational Function

International Journal of Comparative Psychology ◽

10.46867/ijcp.2014.27.04.01 ◽

2014 ◽

Vol 27 (4) ◽

Author(s):

Stanley J. Weiss

Keyword(s):

Stimulus Control ◽

Differential Reinforcement ◽

Neutral Group ◽

Process Learning ◽

Control Research ◽

Operant Contingency ◽

Discriminative Property ◽

Lever Pressing ◽

Series Of Experiments ◽

First Time

Though differential reinforcement, a discriminative stimulus (SD) acquires two properties. The operant contingency is responsible for the SDs response-discriminative property. However, as stimulus control develops an SD also acquires incentive-motivational properties through its association with reinforcement changes. A systematic series of experiments are described that breaks the usual co-variation of response and reinforcement rates in most discriminative operant situations. In three groups, SDs (a tone and a light) occasioned steady moderate lever pressing in rats that ceased when neither SD was present. Probably of reinforcement in these SDs, relative to when both were off, was systematically manipulated to make them incentive-motivationally excitatory, neutral or inhibitory. In each SD, for the “excitatory” group reinforcement (food) probability increased from 0 to 100%, for the “neutral” group it was unchanged and for the “inhibitory” group it decreased from 100 to 0%. Although behaviorally indistinguishable in training, a stimulus-compounding assay revealed that tone-plus-light tripled response rate in the incentive-excitatory group, doubled rate in the incentive-neutral group and didn’t increase rate in the incentive-inhibitory group – producing the instrumentally derived incentive-motivational function for the first time. This is discussed context of two-process learning theory, a functional analysis of transfer-of-control research plus how the response-discriminative and incentive-motivational properties acquired by an SD contribute to the stimulus control of behavior.

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Channeling and radiation experiments at SLAC

International Journal of Modern Physics A ◽

10.1142/s0217751x19430061 ◽

2019 ◽

Vol 34 (34) ◽

pp. 1943006

Author(s):

U. Wienands ◽

S. Gessner ◽

M. J. Hogan ◽

T. Markiewicz ◽

T. Smith ◽

...

Keyword(s):

Gamma Rays ◽

Beam Energy ◽

Narrow Band ◽

Test Facility ◽

Test Beam ◽

High Beam ◽

Silicon Crystals ◽

Volume Reflection ◽

Series Of Experiments ◽

First Time

Since 2014, a SLAC-Aarhus-Ferrara-CalPoly collaboration augmented by members of ANL and MIT has performed electron and positron channeling experiments using bent silicon crystals at the SLAC End Station A Test Beam as well as the FACET accelerator test facility. These experiments have revealed a remarkable channeling efficiency of about 24% under our conditions. Volume reflection is even more efficient with almost the whole beam taking part in the reflection process. A positron experiment demonstrated quasi-channeling oscillations for the first time at high beam energy. In our most recent experiment we measured the spectrum of gamma radiation for crystal orientations covering channeling and volume reflection. This series of experiments supports the development of more advanced crystalline devices capable e.g. of producing narrow-band gamma rays with electron beams or studying the interaction of the electrons with the wakefields generated in the crystal at high beam intensity.

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Regularized Evolution for Image Classifier Architecture Search

Proceedings of the AAAI Conference on Artificial Intelligence ◽

10.1609/aaai.v33i01.33014780 ◽

2019 ◽

Vol 33 ◽

pp. 4780-4789 ◽

Cited By ~ 206

Author(s):

Esteban Real ◽

Alok Aggarwal ◽

Yanping Huang ◽

Quoc V. Le

Keyword(s):

Neural Network ◽

Learning Algorithm ◽

State Of The Art ◽

Simple Method ◽

Current State ◽

Network Topologies ◽

Comparable Accuracy ◽

Tournament Selection ◽

Complex Architecture ◽

First Time

The effort devoted to hand-crafting neural network image classifiers has motivated the use of architecture search to discover them automatically. Although evolutionary algorithms have been repeatedly applied to neural network topologies, the image classifiers thus discovered have remained inferior to human-crafted ones. Here, we evolve an image classifier— AmoebaNet-A—that surpasses hand-designs for the first time. To do this, we modify the tournament selection evolutionary algorithm by introducing an age property to favor the younger genotypes. Matching size, AmoebaNet-A has comparable accuracy to current state-of-the-art ImageNet models discovered with more complex architecture-search methods. Scaled to larger size, AmoebaNet-A sets a new state-of-theart 83.9% top-1 / 96.6% top-5 ImageNet accuracy. In a controlled comparison against a well known reinforcement learning algorithm, we give evidence that evolution can obtain results faster with the same hardware, especially at the earlier stages of the search. This is relevant when fewer compute resources are available. Evolution is, thus, a simple method to effectively discover high-quality architectures.

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Peculiaries of interactions between proteins of the macroglobulin family and with the endocytic receptors (a possible mechanism of transmembrane transfer)

Biomeditsinskaya Khimiya ◽

10.18097/pbmc20115701106 ◽

2011 ◽

Vol 57 (1) ◽

pp. 106-113

Author(s):

V.N. Zorina ◽

R.M. Zorina ◽

N.A. Zorin

Keyword(s):

Low Density Lipoprotein ◽

Density Lipoprotein ◽

Receptor Associated Protein ◽

Leading Role ◽

The Family ◽

Density Lipoprotein Receptor ◽

A Cell ◽

Series Of Experiments ◽

First Time ◽

Lipoprotein Receptor Related Protein

We have conducted a series of experiments, for specification of mechanisms which proteins of the macroglobulin family deliver regulatory substances inside of a cells. We have shown that all members of the family are not only compete for binding to proteinases, but also can interact with each other. We have confirmed that only a complex of alpha-2-macroglobulin (α2-MG) with proteinase is capable to react with the major endocytic receptor (low-density lipoprotein receptor-related protein, LRP). For the first time we have demonstrated, that interaction of α2-MG firstly with proteinase, and then with LRP provokes a progressive conformational consolidation of the multicomplex, which is accompanied by a paradoxical increase of the electrophoretic mobility in comparison with native α2-MG. We suggest that such stepwise conformational consolidation, together with earlier demonstrated charge neutralization (versus pI of internal environments) after interaction firstly with proteinase, and then with LRP, components of is the key moment of the mechanism of transmembrane transfer. Taking into account, that α2-MG transfers a broad spectrum of protein regulators, and interacts not only with LRP, but also with a signal receptor (grp78), and also can regulate (under certain conditions) both own synthesis, and synthesis of LRP and its blocker (receptor - associated protein, RAP), we suggest that this main member of the macroglobulin family plays a leading role in the regulation of intercellular interactions and in the transmission of signal inside of a cell.

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Emotion increases the similarity between neural representations of pictures, but not their perceived similarity.

10.1101/2021.06.21.449164 ◽

2021 ◽

Author(s):

Martina Riberto ◽

Rony Paz ◽

Gorana Pobric ◽

Deborah Talmi

Keyword(s):

Objective Measures ◽

Similarity Analysis ◽

Perceived Similarity ◽

Emotional Stimuli ◽

Search Volume ◽

Neural Representations ◽

Similarity Space ◽

Two Measures ◽

Series Of Experiments ◽

First Time

Emotional similarity refers to the tendency to group stimuli together because they evoke the same feelings in us, even when they look different and have different semantic meanings. It is still unclear which features define the similarity space of emotional categories. Additionally, whether emotional stimuli are perceived as more similar than neutral ones, and whether this difference is paralleled by differences in their neural representations, has never been investigated. We conducted a series of experiments to quantify behavioural similarity, and one that used fMRI and Representation similarity analysis to compute neural similarity. We hypothesised that the similarity between emotional stimuli will be greater than between non-emotional stimuli, paralleled by higher neural similarity among emotional stimuli. We tested these hypotheses with two measures of similarity and two different databases of complex negative and neutral pictures, the second of which allowed us to control semantic similarity. For the first time, we found a decoupling between subjective and objective measures of emotional similarity. Pictures taken from two distinct emotional and neutral categories were perceived as equally similar; however, their neural similarity was higher. This effect was detected in brain clusters localised in a constrained search volume. We conclude that features representing participants similarity space may have different weights in these regions than they do in explicit ratings.

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Identification of Motor and Mental Imagery EEG in Two and Multiclass Subject-Dependent Tasks Using Successive Decomposition Index

Sensors ◽

10.3390/s20185283 ◽

2020 ◽

Vol 20 (18) ◽

pp. 5283 ◽

Cited By ~ 1

Author(s):

Muhammad Tariq Sadiq ◽

Xiaojun Yu ◽

Zhaohui Yuan ◽

Muhammad Zulkifal Aziz

Keyword(s):

Neural Network ◽

Mental Imagery ◽

Practical Applications ◽

The Public ◽

Series Of Experiments ◽

Neural Network Classifiers ◽

Public Datasets ◽

Dependent Tasks ◽

First Time

The development of fast and robust brain–computer interface (BCI) systems requires non-complex and efficient computational tools. The modern procedures adopted for this purpose are complex which limits their use in practical applications. In this study, for the first time, and to the best of our knowledge, a successive decomposition index (SDI)-based feature extraction approach is utilized for the classification of motor and mental imagery electroencephalography (EEG) tasks. First of all, the public datasets IVa, IVb, and V from BCI competition III were denoised using multiscale principal analysis (MSPCA), and then a SDI feature was calculated corresponding to each trial of the data. Finally, six benchmark machine learning and neural network classifiers were used to evaluate the performance of the proposed method. All the experiments were performed for motor and mental imagery datasets in binary and multiclass applications using a 10-fold cross-validation method. Furthermore, computerized automatic detection of motor and mental imagery using SDI (CADMMI-SDI) is developed to describe the proposed approach practically. The experimental results suggest that the highest classification accuracy of 97.46% (Dataset IVa), 99.52% (Dataset IVb), and 99.33% (Dataset V) was obtained using feedforward neural network classifier. Moreover, a series of experiments, namely, statistical analysis, channels variation, classifier parameters variation, processed and unprocessed data, and computational complexity, were performed and it was concluded that SDI is robust for noise, and a non-complex and efficient biomarker for the development of fast and accurate motor and mental imagery BCI systems.

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Semantic closure demonstrated by the evolution of a universal constructor architecture in an artificial chemistry

Journal of The Royal Society Interface ◽

10.1098/rsif.2016.1033 ◽

2017 ◽

Vol 14 (130) ◽

pp. 20161033 ◽

Cited By ~ 5

Author(s):

Edward B. Clark ◽

Simon J. Hickinbotham ◽

Susan Stepney

Keyword(s):

In Silico ◽

Von Neumann ◽

Artificial Chemistry ◽

Viable Offspring ◽

Abstract Description ◽

Series Of Experiments ◽

First Time ◽

Semantic Closure ◽

Simultaneous Evolution ◽

Genomic Material

We present a novel stringmol-based artificial chemistry system modelled on the universal constructor architecture (UCA) first explored by von Neumann. In a UCA, machines interact with an abstract description of themselves to replicate by copying the abstract description and constructing the machines that the abstract description encodes. DNA-based replication follows this architecture, with DNA being the abstract description, the polymerase being the copier, and the ribosome being the principal machine in expressing what is encoded on the DNA. This architecture is semantically closed as the machine that defines what the abstract description means is itself encoded on that abstract description. We present a series of experiments with the stringmol UCA that show the evolution of the meaning of genomic material, allowing the concept of semantic closure and transitions between semantically closed states to be elucidated in the light of concrete examples. We present results where, for the first time in an in silico system, simultaneous evolution of the genomic material, copier and constructor of a UCA, giving rise to viable offspring.

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Bedload transport in two creeks at the ice-free area of the Baranowski Glacier, King George Island, West Antarctica

Polish Polar Research ◽

10.1515/popore-2017-0003 ◽

2017 ◽

Vol 38 (1) ◽

pp. 21-39 ◽

Cited By ~ 11

Author(s):

Joanna Sziło ◽

Robert J. Bialik

Keyword(s):

Water Discharge ◽

Weather Conditions ◽

Arithmetic Mean ◽

Bedload Transport ◽

Water Levels ◽

West Antarctica ◽

Weighted Arithmetic ◽

Granulometric Analysis ◽

First Time

Abstract This paper presents a unique case study and methodology for measurements of the bedload transport in the two, newly created troughs at the forefield of the Baranowski Glacier: Fosa and Siodło creeks. The weather conditions and the granulometric analysis are presented and discussed briefly. Rating curves for the Fosa and Siodło creeks are presented for the first time for this region. Changes of the bedload transport as well as water discharge and water velocity at both creeks are investigated. The hysteresis for the relationships between rate of bedload transport and water discharges were identified showing that for both creeks for the higher water levels a figure of eight loop may be easily recognized. Moreover, a new method for the calculation of bedload transport rate, based on the weighted arithmetic mean instead of the arithmetic mean, is proposed.

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