Interpreting Open- and Closed-Loop Transfer Relations Between Cardiorespiratory Parameters: Lessons Learned from a Computer Model of Beat-to-Beat Cardiovascular Regulation

1997 ◽  
Vol 36 (04/05) ◽  
pp. 237-240
Author(s):  
P. Hammer ◽  
D. Litvack ◽  
J. P. Saul
Keyword(s):  
Computer Model ◽  
Closed Loop ◽  
Computer Models ◽  
Cardiovascular Regulation ◽  
Cardiovascular Control ◽  
Lessons Learned ◽  
Multiple Systems ◽  
Response Characteristics ◽  
Similarities And Differences

Abstract:A computer model of cardiovascular control has been developed based on the response characteristics of cardiovascular control components derived from experiments in animals and humans. Results from the model were compared to those obtained experimentally in humans, and the similarities and differences were used to identify both the strengths and inadequacies of the concepts used to form the model. Findings were confirmatory of some concepts but contrary to some which are firmly held in the literature, indicating that understanding the complexity of cardiovascular control probably requires a combination of experiments and computer models which integrate multiple systems and allow for determination of sufficiency and necessity.

Response Characteristics of a Pulse-Width-Modulated Electrohydraulic Servo

1970 ◽  
Vol 92 (2) ◽  
pp. 204-214 ◽  
Author(s):  
S. C. Tsai ◽  
P. R. Ukrainetz
Keyword(s):  
Pulse Width ◽  
Closed Loop ◽  
Mechanical Load ◽  
Transfer Characteristic ◽  
Double Fourier Series ◽  
Hydraulic Control ◽  
Pulse Width Modulated ◽  
Response Characteristics ◽  
Theoretical Analyses

Methods for analyzing the response characteristics of a pulse-width-modulated electro-hydraulic servomechanism are presented. Except for the modulator, the hydraulic control system is of conventional configuration. The modulator transfer characteristic is derived from a double Fourier series analysis of the pulse-width-modulated signal and this indicates the effect of the modulation parameters on the system performance. The valve flow which controls the mechanical load motion has been shown to be the dominant nonlinearity in a valve-controlled hydraulic system, and the system becomes more complicated due to the valve spool dither which is a consequence of the pulse-width-modulated signal. A dual-input describing function is developed for the equivalent valve flow gain in the determination of the system closed-loop frequency response. A numerical simulation is used to obtain the closed-loop transient response. Experimental verification of the theoretical analyses is carried out on a practical system. Good agreement is obtained between the predicted and the experimental responses.

scholarly journals Potentiometric Response of Solid-State Sensors Based on Ferric Phosphate for Iron(III) Determination

Sensors ◽  
2021 ◽  
Vol 21 (5) ◽  
pp. 1612
Author(s):  
Andrea Paut ◽  
Ante Prkić ◽  
Ivana Mitar ◽  
Perica Bošković ◽  
Dražan Jozić ◽  
...  
Keyword(s):  
Silver Sulfide ◽  
Potential Change ◽  
Linear Potential ◽  
Response Characteristics ◽  
Potentiometric Response ◽  
Best Response ◽  
Body Design ◽  
Long Lifetime ◽  
First Time

A novel ion-selective electrode with membranes based on iron(III) phosphate and silver sulfide integrated into a completely new electrode body design has been developed for the determination of iron(III) cations. The best response characteristics with linear potential change were found in the iron(III) concentration range from 3.97× 10−5 to 10−2 mol L−1. The detection limit was found to be 2.41× 10−5 mol L−1 with a slope of –20.53 ± 0.63 and regression coefficient of 0.9925, while the quantification limit was 3.97× 10−5 M. The potential change per concentration decade ranged from –13.59 ± 0.54 to –20.53 ± 1.56 for Electrode Body 1 (EB1) and from –17.28 ± 1.04 to –24 ± 1.87 for Electrode Body 2 (EB2), which is presented for the first time in this work. The prepared electrode has a long lifetime and the ability to detect changes in the concentration of iron cations within 20 s. Membrane M1 showed high recoveries in the determination of iron cations in iron(III) standard solutions (98.2–101.2%) as well as in two different pharmaceuticals (98.6–106.5%). This proves that this type of sensor is applicable in the determination of ferric cations in unknown samples, and the fact that all sensor parts are completely manufactured in our laboratory proves the simplicity of the method.

Measuring the Hidden Numbers of Human Trafficking Through Multiple Systems Estimation: Lessons Learned and Challenges Outstanding

2021 ◽  
pp. 001112872098719
Author(s):  
Davina Durgana ◽  
Jan van Dijk
Keyword(s):  
Human Trafficking ◽  
Migrant Workers ◽  
Lessons Learned ◽  
Multiple Systems ◽  
State Institutions ◽  
Gender And Age ◽  
Prevalence Estimates ◽  
Trafficking Victims ◽  
Developed Nations ◽  
Further Development

This article takes stock of studies conducted in eight countries to estimate the prevalence of human trafficking by employing the technique of Multiple Systems Estimation on data on victims of human trafficking recorded by state and non-state institutions. It presents an overview of MSE-based prevalence estimates of human trafficking victims per 100,000 inhabitants of these countries, disaggregated by type of exploitation, gender, and age. For some countries it also presents the different likelihoods of various sub-categories of trafficking victims, such as minors and migrant workers, to be detected by authorities and/or NGOs. Next, the article recounts what these studies have taught us about the suitability of applying MSE on existing multi-source databases to estimate the prevalence of trafficking victimization. The article concludes with a discussion on the promises and limitations of MSE and its prospects for further development, especially among developed nations.

An Analysis of Conventional and Self-Aligned four Terminal Resistor Structures for The Determination of The Contact Resistivity from End Resistance Measurements

1986 ◽  
Vol 71 ◽  
Author(s):  
I. Suni ◽  
M. Finetti ◽  
K. Grahn
Keyword(s):  
Finite Element Method ◽  
Finite Element ◽  
Computer Model ◽  
Contact Resistivity ◽  
Experimental Results ◽  
The Finite Element Method ◽  
Model Based ◽  
A Value ◽  
And Diffusion

AbstractA computer model based on the finite element method has been applied to evaluate the effect of the parasitic area between contact and diffusion edges on end resistance measurements in four terminal Kelvin resistor structures. The model is then applied to Al/Ti/n+ Si contacts and a value of contact resistivity of Qc = 1.8×10−7.Ωcm2 is derived. For comparison, the use of a self-aligned structure to avoid parasitic effects is presented and the first experimental results obtained on Al/Ti/n+Si and Al/CoSi2/n+Si contacts are shown and discussed.

Psychological factors of student youth‘s responsible behavior.

2020 ◽  
Vol 89-90 (4-5) ◽  
pp. 93-101
Author(s):  
Tatyana Fadeeva ◽  
Keyword(s):  
Social Responsibility ◽  
Self Esteem ◽  
Psychological Characteristics ◽  
Educational Organizations ◽  
Social Desirability Scale ◽  
Self Confidence ◽  
Responsible Behavior ◽  
Symptom Complex ◽  
Similarities And Differences

The article considers the problem of studying the determinants of the types of responsible behavior of young people. It is assumed that there are similarities and differences in the determination of the types of responsible behavior of the youth. The study involved 70 students (average age – 22 years old, SD = 2.19; men – 12%). We used the standardized methods "Questionnaire for the diagnosis of the personal symptom complex of responsibility" (Kocharyan I.A.), "Methods for the study of self-attitude" (Panteleev S.R.), the questionnaire "Determining the level of self-esteem" (Kovalev S.V.), "Social Desirability Scale" (D. Crown, D. Marlowe). We established that the most pronounced types of social behavior of youth are "ethics" and "self-sacrifice". It is shown that the severity of the type of social responsibility is determined by various combinations of psychological characteristics. The most complex regression equation characterizes the type of responsible behavior “Normalizations”. The least pronounced prediction of responsible behavior was revealed in relation to its types: "Fidelity to principle" and "Self-confidence". The results of this study can be useful for further study of the problems of social responsibility, as well as for the development of programs for the formation of youth's social responsibility in educational organizations.

scholarly journals SIMULATION TESTS OF EXTINGUISHING PROCESS USING MIST NOZZLES WITH APPLICATION OF HYBRID FIRE MODEL

2016 ◽  
Vol 22 (4) ◽  
pp. 573-583 ◽  
Author(s):  
Jerzy GAŁAJ ◽  
Marek KONECKI ◽  
Ritoldas ŠUKYS
Keyword(s):  
Heat Flux ◽  
Computer Model ◽  
Input Data ◽  
Elementary Cell ◽  
Characteristic Parameters ◽  
Computational Cell ◽  
Fire Model ◽  
Fire Extinguishing ◽  
Unique Approach

The article presents a computer model of the fire extinguishing process using mist nozzles. A previously developed hybrid fire model was used for this purpose. Assumptions and relationships were given to represent a math­ematical model of extinguishing process, which comprises a unique approach to the determination of sprinkling area in an elementary cell of field fire model. A description of simulation tests of the model was given for several different input data, differing by mean diameters of droplets. This enabled a study of their effects on such output parameters as received heat flux, temperature and rate of its growth. For one selected computational cell located on the axis of the nozzle at floor level having the coordinates [10, 10, 1], the obtained results were presented in the form of heat flux and temperature. To simplify the analysis, characteristic parameters of particular curves were listed in the table. Conclusions formulated on the basis of results obtained during tests were specified at the end of work. They confirmed the expected regularity assuming that the extinguishing process was more effective in the case of droplets of a smaller diameter and greater sprinkling intensity. This allows assessing the degree, to which these stream parameters affect the extinguishing effectiveness.

scholarly journals Expressionism in European and Chinese painting (late XIX – early XXI centuries)

2020 ◽  
pp. 27-46
Author(s):  
Jitai Wang
Keyword(s):  
Comparative Analysis ◽  
Mutual Influence ◽  
Cultural Factors ◽  
Chinese Painting ◽  
Oil Painting ◽  
New Concepts ◽  
Similarities And Differences ◽  
The Individual ◽  
The Impact

This article examines the impact of Chinese traditional painting upon the formation of Western expressionism, as well as interprets the influence of Western expressionism upon Chinese painting in expressionist manner of different periods. The author reveals the mutual influence, similarities and differences between Western expressionism and Chinese painting in expressionist manner, Chinese imagery oil painting, Chinese colored ink painting, and Chinese imagery painting in Western style. Based on correlation between the spiritual ideology of painting and artistic form, the author carries out a comparative analysis of spiritual and formal factors of Chinese and Western painting systems for the purpose of determination of their mutual influence, and how it affects the emergence of new concepts in painting. The structure of brush stroke of the artist defines his aesthetic spirit. The article determines the “cyclic” nature of interinfluence processes between Chinese and Western painting systems that stimulate the development of human civilization. The analysis of corresponding cultural factors allows assessing the individual artistic characteristics of painting. Both, Chinese and Western painting systems entered the period when spiritual ideology of painting interacts with the artistic forms, opening the era of “globalization” of the language of painting.

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