Control of the contractility of the myocardium in a feedback system

1966 ◽  
Vol 28 (2) ◽  
pp. 195-205 ◽  
Author(s):  
Sidney Roston
Keyword(s):  
Feedback System ◽  
Contractility Of The Myocardium

Experiments with a scanning tunneling microscope (STM) mounted in a scanning electron microscope (SEM)

1986 ◽  
Vol 44 ◽  
pp. 636-639
Author(s):  
Oliver C. Wells ◽  
Mark E. Welland
Keyword(s):  
Electron Microscope ◽  
Scanning Electron Microscope ◽  
Mechanical Stability ◽  
Tunneling Current ◽  
Feedback System ◽  
Scanning Tunneling ◽  
Surface Profiling ◽  
Close Proximity ◽  
Metal Tip ◽  
Scanning Electron

Scanning tunneling microscopes (STM) exist in two versions. In both of these, a pointed metal tip is scanned in close proximity to the specimen surface by means of three piezos. The distance of the tip from the sample is controlled by a feedback system to give a constant tunneling current between the tip and the sample. In the low-end STM, the system has a mechanical stability and a noise level to give a vertical resolution of between 0.1 nm and 1.0 nm. The atomic resolution STM can show individual atoms on the surface of the specimen.A low-end STM has been put into the specimen chamber of a scanning electron microscope (SEM). The first objective was to investigate technological problems such as surface profiling. The second objective was for exploratory studies. This second objective has already been achieved by showing that the STM can be used to study trapping sites in SiO2.

Clinical Renal Function Testing by External Double Isotope Monitoring Technique

1971 ◽  
Vol 10 (01) ◽  
pp. 16-24
Author(s):  
J. Fog Pedersen ◽  
M. Fog Pedersen ◽  
Paul Madsen
Keyword(s):  
Renal Function ◽  
Glomerular Filtration Rate ◽  
Glomerular Filtration ◽  
Plasma Flow ◽  
Filtration Rate ◽  
Renal Plasma Flow ◽  
Correlation Coefficients ◽  
Feedback System ◽  
Effective Renal Plasma Flow ◽  
Advantages And Disadvantages

SummaryAn accurate catheter-free technique for clinical determination simultaneouslyof glomerular filtration rate and effective renal plasma flow by means of radioisotopes has been developed. The renal function is estimated by the amount of radioisotopes necessary to maintain a constant concentration in the patient’s blood. The infusion pumps are steered by a feedback system, the pumps being automatically turned on when the radiation measured over the patient’s head falls below a certain preset level and turned off when this level is again readied. 131I-iodopyracet was used for the estimation of effective renal plasma flow and125I-iothalamate estimation of the glomerular filtration rate. These clearances were compared to the conventional bladder clearances and good correlation was found between these two clearance methods (correlation coefficients 0.97 and.90 respectively). The advantages and disadvantages of this new clearance technique are discussed.

Continuous Estimation of CO2 Production during Exercise

1997 ◽  
Vol 36 (04/05) ◽  
pp. 368-371
Author(s):  
R. Soma ◽  
Y. Yamamoto
Keyword(s):  
Fuzzy Logic ◽  
Steady State ◽  
Infusion Rate ◽  
Feedback System ◽  
Whole Body ◽  
Co2 Production ◽  
Cycle Exercise ◽  
Continuous Estimation ◽  
Breath Measurement ◽  
13Co2 Enrichment

Abstract.A new method was developed for continuous isotopic estimation of human whole body CO2 rate of appearance (Ra) during non-steady state exercise. The technique consisted of a breath-by-breath measurement of 13CO2 enrichment (E) and a real-time fuzzy logic feedback system which controlled NaH13CO3 infusion rate to achieve an isotopic steady state. Ra was estimated from the isotope infusion rate and body 13CO2 enrichment which was equal to E at the isotopic steady state. During a non-steady state incremental cycle exercise (5 w/min or 10 w/min), NaH13CO3 infusion rate was successfully increased by the action of feedback controller so as to keep E constant.

Supercontinuum laser-based monochromatic radiant source for detector spectral responsivity characterization in the range 0.9–1.6 μm using absolute cryogenic radiometer

2020 ◽  
pp. 28-33
Author(s):  
A. Yu. Dunaev ◽  
A. S. Baturin ◽  
V. N. Krutikov ◽  
S. P. Morozova
Keyword(s):  
Power Distribution ◽  
Spectral Power ◽  
Feedback System ◽  
Operating Mode ◽  
Spectral Responsivity ◽  
Spectral Power Distribution ◽  
Cryogenic Radiometer ◽  
Supercontinuum Laser ◽  
Radiant Power ◽  
Double Monochromator

An improved monochromatic radiant source with spectral bandwidth of 4 nm based on supercontinuum laser and a double monochromator was included in absolute cryogenic radiometer-based facility to improve the accuracy of spectral responsivity measurement in the range 0.9–1.6 μm. The developed feedback system ensures stabilization of monochromatic radiant power with standard deviation up to 0.025 %. Radiant power that proceeds detector under test or absolute cryogenic radiometer varies from 0.1 to 1.5 mW in dependence of wavelength. The spectral power distribution of its monochromatic source for various operating mode is presented.

Optimal Model Reference Control Scheme Design for Nonlinear Strict-Feedback Systems

2020 ◽  
Vol 38 (9A) ◽  
pp. 1342-1351
Author(s):  
Musadaq A. Hadi ◽  
Hazem I. Ali
Keyword(s):  
Reference Model ◽  
Feedback System ◽  
Optimization Method ◽  
Feedback Systems ◽  
Model Reference ◽  
Scheme Design ◽  
Model Reference Control ◽  
Control Scheme ◽  
Lyapunov Stability Analysis ◽  
Strict Feedback

In this paper, a new design of the model reference control scheme is proposed in a class of nonlinear strict-feedback system. First, the system is analyzed using Lyapunov stability analysis. Next, a model reference is used to improve system performance. Then, the Integral Square Error (ISE) is considered as a cost function to drive the error between the reference model and the system to zero. After that, a powerful metaheuristic optimization method is used to optimize the parameters of the proposed controller. Finally, the results show that the proposed controller can effectively compensate for the strictly-feedback nonlinear system with more desirable performance.

Propaganda as a means of implementing the ideological function of the state

2020 ◽  
Vol 2020 (3) ◽  
pp. 10-14
Author(s):  
Aleksey Bredikhin ◽  
Andrei Udaltsov
Keyword(s):  
Mass Media ◽  
Feedback System ◽  
Legal Framework ◽  
The State ◽  
The Political ◽  
Special Position ◽  
Equal Footing ◽  
Constitutional Order ◽  
Political Situation ◽  
The Mass Media

In the article the authors analyze the essence of propaganda as a means of implementing ideological function of the state. It is noted that propaganda is a mechanism of spreading information persuasive influence in the interpretation and estimation of state power representatives. The structure of propaganda is determined: beneficiary of propaganda, subjects of propaganda, content of propaganda, channels of realization of propaganda, addressee of propaganda, feedback system. Types of propaganda are distinguished: political, axiological, educational, preventive. The authors come to the conclusion that the basic directions and the propaganda content are established in normative acts and the programs and organizational actions accepted according to them. Along with the implementation of propaganda, the ideological function is implemented by prohibiting or restricting propaganda or other dissemination of information that endangers the foundations of the constitutional order and is otherwise aimed at destabilizing the political situation in the State, as well as prohibiting the propaganda of ideas that may harm the foundations of morality and morality. The mass media are essential in carrying out propaganda. The State widely uses this resource on an equal footing with other actors to disseminate ideas of public importance and uses the services of various communication agencies. However, the state forms a legal framework for the mass media, their rights and limitations, which still determines the special position of the state in this process.

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