scholarly journals Relationship of postsaccadic oscillation with the state of the pupil inside the iris and with cognitive processing

2020 ◽  
Vol 123 (2) ◽  
pp. 484-495
Author(s):  
Shimpei Yamagishi ◽  
Makoto Yoneya ◽  
Shigeto Furukawa
Keyword(s):  
Physical Model ◽  
Cognitive Processing ◽  
Pupil Size ◽  
Dynamic Properties ◽  
Viscosity Coefficient ◽  
Neural System ◽  
The State ◽  
Cognitive Tasks ◽  
Elasticity Coefficient ◽  
Task Dependence

Recent studies using video-based eye tracking have presented accumulating evidence that postsaccadic oscillation defined in reference to the pupil center (PSOp) is larger than that to the iris center (PSOi). This indicates that the relative motion of the pupil reflects the viscoelasticity of the tissue of the iris. It is known that the pupil size controlled by the sphincter/dilator pupillae muscles reflects many aspects of cognition. A hypothesis derived from this fact is that cognitive tasks affect the properties of PSOp due to the change in the state of these muscles. To test this hypothesis, we conducted pro- and antisaccade tasks for human participants and adopted the recent physical model of PSO to evaluate the dynamic properties of PSOp/PSOi. The results showed the dependence of the elasticity coefficient of the PSOp on the antisaccade task, but this effect was not significant for the PSOi. This suggests that cognitive tasks such as antisaccade tasks affect elasticity of the muscle of the iris. We found that the trial-by-trial fluctuation in the presaccade absolute pupil size correlated with the elasticity coefficient of PSOp. We also found the task dependence of the viscosity coefficient and overshoot amount of PSOi, which probably reflects the dynamics of the entire eyeball movement. The difference in task dependence between PSOp and PSOi indicates that the separate measures of these two can be means to distinguish factors related to the oculomotor neural system from those related to the physiological states of the iris tissue. NEW & NOTEWORTHY The state of the eyeball varies dynamically moment by moment depending on underlying neural/cognitive processing. Combining simultaneous measurements of pupil-centric and iris-centric movements and a recent physical model of postsaccadic oscillation (PSO), we show that the pupil-centric PSO is sensitive to the type of saccade task, suggesting that the physical state of the iris muscles reflects the underlying cognitive processes.

STUDY OF THE DYNAMICS OF PULSE HYDRAULIC MECHANISMS WITH PNEUMATIC STROKE CHAMBER

2021 ◽  
Vol 2 ◽  
pp. 159-165
Author(s):  
A.V. GORIN ◽  
R.N. POLYAKOV ◽  
M.A. GRYADUNOVA ◽  
I.V. RODICHEVA
Keyword(s):  
Physical Model ◽  
Relative Energy ◽  
The State ◽  
Energy Losses ◽  
Paper Briefly ◽  
Cross Sectional ◽  
Working Chamber ◽  
Hydraulic Machines ◽  
Pneumatic Chamber ◽  
Hydraulic Mechanism

The paper briefly outlines the state of development of impulse technology. The schemes of hydraulic machines of impulse action with percussion mechanisms of the sixth and seventh classes are presented. The calculation of impulse mechanisms with a pneumatic chamber of the working stroke is given. The physical model of the drain pipeline is presented. Shown is a diagram of the forces acting on the striker during the working stroke. The dependence of the relative energy losses on the ratios of the cross-sectional areas of the working chamber and the drain pipeline is presented. Recommendations are given for the use of a pneumatic accumulator in the drain branch of the pipeline of a pulsed hydraulic mechanism with a pneumatic chamber of the working stroke

scholarly journals Smart air purifier suitable for small public spaces

2019 ◽  
Vol 28 ◽  
pp. 01015
Author(s):  
Pawel Idziak ◽  
Michal Gojtowski
Keyword(s):  
Pressure Drop ◽  
Physical Model ◽  
Air Temperature ◽  
Public Spaces ◽  
The State ◽  
Pm 2.5 ◽  
Air Purifier ◽  
Arduino Uno

The article presents the concept and implemented, functional physical model of a mobile air purifier for small public spaces or apartments. The purifier is a compact, controlled by microcontroller of the Arduino UNO series. The model is equipped with a set of sensors allowing to determine the content of PM 2.5 contaminants. After exceeding the adopted threshold in the software, the system automatically starts the process of air filtering. The following factors are measured: solid contamination content, humidity and air temperature as well as pressure drop on built-in filters. The purifier absorbs solid pollutants and reduces VOC pollutants. The system has been equipped with a screen informing the user about air parameters and the state of the filter contamination.

scholarly journals Balancing Energy Processes in Turbine Engines

2015 ◽  
Vol 21 (4) ◽  
pp. 48-56
Author(s):  
Włodzimierz Balicki ◽  
Paweł Głowacki ◽  
Stefan Szczeciński ◽  
Zbigniew Korczewski ◽  
Adam Kozakiewicz ◽  
...  
Keyword(s):  
Physical Model ◽  
Dynamic Properties ◽  
Turbine Engines ◽  
Combined System ◽  
Long Distance ◽  
Turbofan Engines ◽  
Marine Propulsion ◽  
Balancing Energy ◽  
Marine Applications ◽  
Energy Processes

Abstract The article discusses the issue of balancing energy processes in turbine engines in operation in aeronautic and marine propulsion systems with the aim to analyse and evaluate basic operating parameters. The first part presents the problem of enormous amounts of energy needed for driving fans and compressors of the largest contemporary turbofan engines commonly used in long-distance aviation. The amounts of the transmitted power and the effect of flow parameters and constructional properties of the engines on their performance and real efficiency are evaluated. The second part of the article, devoted to marine applications of turbine engines, presents the energy balance of the kinetic system of torque transmission from main engine turbines to screw propellers in the combined system of COGAG type. The physical model of energy conversion processes executed in this system is presented, along with the physical model of gasodynamic processes taking place in a separate driving turbine of a reversing engine. These models have made the basis for formulating balance equations, which then were used for analysing static and dynamic properties of the analysed type of propulsion, in particular in the aspect of mechanical loss evaluation in its kinematic system.

Pantograph-Catenary Model Simulation Based on DSPACE

2012 ◽  
Vol 256-259 ◽  
pp. 2967-2970
Author(s):  
Shuai Lin ◽  
Zhi Qiang Ju
Keyword(s):  
Real Time ◽  
Physical Model ◽  
High Speed ◽  
Model Simulation ◽  
The State ◽  
Rail Transit ◽  
High Speed Rail ◽  
Simulation Based ◽  
Primary Means ◽  
The City

With the city subway and high speed rail opened, development of rail transit pays more and more people's attention. And the pantograph is the primary means of train running at high speed to get power. Using Simulink and dSPACE in combination, real-time captures the pantograph and catenary's motion. According to the state of the pantograph’s motion, analyses physical model, so as to achieve the purpose of independent manufacturing pantograph pantograph.

scholarly journals A New Class of Almost Ricci Solitons and Their Physical Interpretation

2016 ◽  
Vol 2016 ◽  
pp. 1-6
Author(s):  
K. L. Duggal
Keyword(s):  
Physical Model ◽  
Dynamic Properties ◽  
Fluid Velocity ◽  
General Relation ◽  
Ricci Soliton ◽  
Field Equations ◽  
Open Problems ◽  
Matter Tensor ◽  
Imperfect Fluid ◽  
Almost Ricci Soliton

We establish a link between a connection symmetry, called conformal collineation, and almost Ricci soliton (in particular Ricci soliton) in reducible Ricci symmetric semi-Riemannian manifolds. As a physical application, by investigating the kinematic and dynamic properties of almost Ricci soliton manifolds, we present a physical model of imperfect fluid spacetimes. This model gives a general relation between the physical quantities (u,μ,p,α,η,σij) of the matter tensor of the field equations and does not provide any exact solution. Therefore, we propose further study on finding exact solutions of our viscous fluid physical model for which it is required that the fluid velocity vector u be tilted. We also suggest two open problems.

scholarly journals The rhythm of cognition – Effects of an auditory beat on oculomotor control in reading and sequential scanning

2018 ◽  
Vol 11 (2) ◽  
Author(s):  
Elke B. Lange ◽  
Aleksandra Pieczykolan ◽  
Hans A. Trukenbrod ◽  
Lynn Huestegge
Keyword(s):  
Eye Movement ◽  
Cognitive Processing ◽  
Movement Control ◽  
Movement Behavior ◽  
Oculomotor Control ◽  
Background Music ◽  
Cognitive Tasks ◽  
Text Reading ◽  
Musical Tempo ◽  
Sequential Scanning

Eye-movement behavior is inherently rhythmic. Even without cognitive input, the eyes never rest, as saccades are generated 3 to 4 times per second. Based on an embodied view of cognition, we asked whether mental processing in visual cognitive tasks is also rhythmic in nature by studying the effects of an external auditory beat (rhythmic background music) on saccade generation in exemplary cognitive tasks (reading and sequential scanning). While in applied settings background music has been demonstrated to impair reading comprehension, the effect of musical tempo on eye-movement control during reading or scanning has not been investigated so far. We implemented a tempo manipulation in four steps as well as a silent baseline condition, while participants completed a text reading or a sequential scanning task that differed from each other in terms of underlying cognitive processing requirements. The results revealed that increased tempo of the musical beat sped up fixations in text reading, while the presence (vs. absence) of the auditory stimulus generally reduced overall reading time. In contrast, sequential scanning was unaffected by the auditory pacemaker. These results were supported by additionally applying Bayesian inference statistics. Our study provides evidence against a cognitive load account (i.e., that spare resources during low-demand sequential scanning allow for enhanced processing of the external beat). Instead, the data suggest an interpretation in favor of a modulation of the oculomotor saccade timer by irrelevant background music in cases involving highly automatized oculomotor control routines (here: in text reading).

scholarly journals Information Circulation in The Advanced Neural Activities of Central Neural System

2020 ◽  
Author(s):  
Fayang Ma
Keyword(s):  
Neural Circuits ◽  
Dynamic Properties ◽  
Long Term Potentiation ◽  
Neural System ◽  
Neural Signals ◽  
Term Potentiation ◽  
Neural Information ◽  
Information Circulation ◽  
Different Levels

Long-Term Potentiation(LTP) and Long-Term Depression(LTD) are two major forms of synaptic plasticity, which are also two well-know functional and unit activities involved in high advanced central neural system(CNS) activities, like memory. But we still know little about how the advanced CNS activities are organized in the brain and in the level of organism. Based on the current understanding and experimental evidence of neurology, we propose the term “Information Circulation” to summarize the current understandings for advanced CNS activities, and we define it as separately input neural signals finally converge in different levels of CNS and interact with each other, then neural information are circulated and processed in different levels of CNS to give out orders for next body actions. This review provides a detailed description for the functional organizations of advanced CNS activities in the term of Information Circulation. This article outlines the receiving of outside stimulation and transmission of neural information, especially transmission and procession of visual bioelectrical signals, then we described neural circuits of Information Circulation in advanced CNS activities, the corresponding specificity and dynamic properties of neural circuits, different sensation linkages, and neural synchronization for information circulation to produce consciousness in CNS. In conclusion, Information Circulation is defined as an important signature involved in advanced CNS activities.

Implementing the Extended Reduced Order Physical Model Into Commercialized Software Packages: Implementing Modal Constraints Into Software Packages

2003 ◽  
Author(s):  
Takahito Sagane ◽  
Takao Kinoshita ◽  
Hiroshi Tajima ◽  
Kazuto Seto
Keyword(s):  
Physical Model ◽  
Dynamic Properties ◽  
Flexible Structures ◽  
Rigid Bodies ◽  
Elastic Deformations ◽  
Reduced Order ◽  
Constraint Equations ◽  
Software Packages ◽  
Augmented Formulation ◽  
Value Decomposition

In this paper, the extended reduced order physical model, which is developed to represent dynamics of flexible structures in multibody systems, is implemented to general multibody formulations. The elastic deformations are described using vibration modes associated with the rigid bodies that are effectively defined using dynamic properties of the system in this reduced order modeling method. The recursive formulation and the augmented formulation are used to develop the constraint equations associated with the connections between the reference body and the several rigid bodies in the modal representations used to modal elastic deformations. For this purpose, the n-body constraint is developed for the recursive formulations, while these constraint equations are transformed into the form that is suitable for the augmented formulation using the singular value decomposition or QR decomposition. The use of the formulations in this paper allows for the implementation of the extended reduced order physical model into the commercial multibody codes such as SIMPACK, ADAMS, and DADS.

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