scholarly journals Developing A Method for Estimation of Tightness Based on Calibration Characteristics

2018 ◽  
Vol 7 (4.36) ◽  
pp. 25
Author(s):  
Yu.S. Asadova ◽  
M.V. Nemenko ◽  
A.M. Volodina
Keyword(s):  
Measuring Chamber ◽  
Throttle Device

This article discusses methods of assessing tightness of mass-produced products. In order to reduce errors in the calibration of gas analytical leak detectors, a method is proposed which is based on transferring a certain number of molecules from the measuring chamber. This is done by means of a throttle device called frequency resistance. Based on the tests performed, results of the study are displayed.

scholarly journals Large-Volume Liquid Scintillation Counting of Carbon-14

Radiocarbon ◽  
1980 ◽  
Vol 22 (2) ◽  
pp. 417-427 ◽  
Author(s):  
Lorenz Eichinger ◽  
Werner Rauert ◽  
Josef Salvamoser ◽  
Manfred Wolf
Keyword(s):  
Detection Limit ◽  
Liquid Scintillation Counting ◽  
Liquid Scintillation ◽  
Scintillation Counting ◽  
Measuring Chamber ◽  
Carbon 14 ◽  
Experimental Detection ◽  
Scintillation Solution ◽  
Special Measuring ◽  
Experimental Detection Limit

Efforts have been undertaken to further improve the relatively simple technique of low-level liquid scintillation counting of 14C. Two different approaches have been made. By synthesizing more benzene for 14C measurement than usual (with up to 19.5g of carbon) an experimental detection limit of about 0.1 percent modern has been achieved (97.5% confidence level, 1000 min). Absorption of CO2 with up to 5.3g of carbon in 160ml of an absorbent-scintillation solution and counting in a special measuring chamber resulted in an experimental detection limit of about 1 percent modern, with the sample preparation taking only 1 hour. The detection limits achieved by the two techniques correspond to 14C ages of about 55,000 and 35,000 years BP, respectively.

A new method of measuring skin humidity

1976 ◽  
Vol 41 (2) ◽  
pp. 256-258 ◽  
Author(s):  
H. Reinhart ◽  
G. Brenneisen
Keyword(s):  
Relative Humidity ◽  
Switching Time ◽  
Time Measurement ◽  
Climatic Conditions ◽  
Logic Circuit ◽  
Simple Circuit ◽  
Measuring Chamber ◽  
Resistance Bridge ◽  
Temperature Recording ◽  
Long Time

A device suitable for the long-time measurement of relative skin humidity is described. This is a simple circuit with a resistance bridge for lithium chloride sensors connected to a digitally steered logic circuit, which causes dried air to stream intermittently through a measuring chamber placed on the skin in such a way that the relative humidity over the skin is maintained at a constant level. The number of switching time periods is proportional to the relative humidity (secretion performance) of the skin and can be counted, recorded, or directly fed into a digital calculator. The apparatus, including a two-channel version with skin temperature recording, has proved useful in sleep investigations under extreme climatic conditions.

scholarly journals Improved system for identifying biological tissue temperature using electrical impedance tomography

2018 ◽  
Vol 158 ◽  
pp. 01019 ◽  
Author(s):  
Evgeniy Korolyuk ◽  
Konstantin Brazovskii
Keyword(s):  
Electrical Impedance ◽  
Saline Water ◽  
Broad Band ◽  
Experimental Studies ◽  
Impedance Spectrum ◽  
Target Object ◽  
Tissue Temperature ◽  
Band Spectrum ◽  
Measuring Chamber ◽  
Impedance Tomography

This paper proposes a cheap and compact medical system that determines the temperature of an object using broadband impedance tomography. This system can be used in medicine to visualize ice structure in tissue during cryosurgical operations, as well as for fault diagnosis and location in studied industrial objects. These effects are achieved by measuring electrical impedance between electrode pairs in the measuring chamber. The assembled prototype is compact, consumes little power, and allows to non-invasively determine the impedance of a target object in real time. The research included experimental studies to determine the dependence of the impedance spectrum of saline water and muscle tissue on temperature in broad band spectrum, which allowed to obtain the dependence of total electrical impedance of target objects on temperature.

Jet propulsion of the calycophoran siphonophores Chelophyes and Abylopsis

1982 ◽  
Vol 62 (2) ◽  
pp. 263-276 ◽  
Author(s):  
Q. Bone ◽  
E. R. Trueman
Keyword(s):  
Measuring Chamber ◽  
Free Swimming ◽  
Jet Propulsion ◽  
The Cost

Jet propulsion in the small siphonophores Chelophyes and Abylopsis was investigated by measuring chamber pressures and thrust exerted in tethered nectophores, and by cinephotography of free swimming colonies. Although of similar design, the two siphon-ophores swim at different speeds, and with very different chamber pressures in the locomotor nectophores. Estimates of drag incurred during swimming, and of the cost of the process in the two forms are discussed.

scholarly journals Discussion on Flow-Through Phenomena in the Air Gauge Cascade

2017 ◽  
Vol 11 (1) ◽  
pp. 38-46 ◽  
Author(s):  
Czesław Janusz Jermak
Keyword(s):  
Static Characteristic ◽  
Back Pressure ◽  
The Other ◽  
Measuring Chamber ◽  
Measuring Point ◽  
Air Stream ◽  
Flow Through ◽  
Nozzle Head ◽  
Complex Phenomena ◽  
The Impact

Abstract In the paper, the flow-through phenomena in the air gauge are under discussion form the thermodynamic and gasodynamic perspective. The main elements of the cascade are considered the inlet nozzle (restriction), measuring chamber and the measuring nozzle with the measuring slot (displacement between the nozzle head and measured surface). The purpose of the analysis was to point out the impact on the metrological characteristics of the air gauge. In particular, attention was paid to the airflow through the measuring slot. Here, the complex phenomena take place, among others the supersonic areas and a “bubble ring,” which cause discontinuity and hysteresis in the static characteristic. On the other hand, the air stream expansion after the restriction (inlet nozzle) is observed in the measuring chamber. The point of the above discussion was to work out some recommendation on the nozzles geometry and the localization of the back-pressure measuring point in the chamber.

scholarly journals DRUGAS: implantable telemetric system for measuring the portal venous pressure: assembly aspects

2017 ◽  
Vol 3 (2) ◽  
pp. 123-126
Author(s):  
Roland Fischer ◽  
Jens Weidenmüller ◽  
Michael Görtz ◽  
Thorsten Goettsche ◽  
Wilfried Mokwa
Keyword(s):  
Venous Pressure ◽  
Measuring System ◽  
Measuring Chamber ◽  
Small Flow ◽  
Telemetric System ◽  
System Requirements ◽  
Main Components ◽  
High Degree ◽  
Specific Metal ◽  
Shape And Size

AbstractDeveloping an implantable, telemetric pressure measuring system for venous applications makes a high degree of miniaturization necessary. Thus the influence on the measurement environment is minimized and the risk of thrombosis at small flow blood velocities is decreased. But these systems are limited in terms of accuracy and resolution. The asked system requirements could only be reached by optimising the assembly and encapsulation techniques. To achieve the high degree of miniaturization numerical simulations were performed on the shape and size of the implant and led to the development of a specific metal housing consisting of two main components. A small measuring chamber will be placed into the portal vein and is rigidly fixed to a flat circular part that contains the pressure sensor chip and a transponder board and will be located outside on top of the vein. The main focus of the assembly process was based on a stress-free design and mounting of the components.

scholarly journals A Recent Electronic Control Circuit to a Throttle Device

Electronics ◽  
2020 ◽  
Vol 9 (1) ◽  
pp. 191 ◽  
Author(s):  
Leonardo Acho ◽  
Gisela Pujol-Vázquez ◽  
José Gibergans-Báguena
Keyword(s):  
Gasoline Engine ◽  
Control Strategies ◽  
Electronic Control Unit ◽  
Control Unit ◽  
Control Circuit ◽  
Electronic Control ◽  
Control Scheme ◽  
Control Objective ◽  
Electronic Controller ◽  
Throttle Device

The main objective of this paper was to conceive a new electronic control circuit to the throttle device. The throttle mechanical actuator is the most important part in an automotive gasoline engine. Among the different control strategies recently reported, an easy to implement control scheme is an open research topic in the analog electronic engineering field. Hence, we propose using the nonlinear dwell switching control theory for an analog electronic control unit, to manipulate an automotive throttle plate. Due to the switching mechanism commuting between a stable and an unstable controllers, the resultant closed-loop system is robust enough to the control objective. This fact is experimentally evidenced. The proposed electronic controller uses operational amplifiers along with an Arduino unit. This unit is just employed to generate the related switching signal that can be replaced by using, for instance, the timer IC555. Thus, this study is a contribution on design and realization of an electronic control circuit to the throttle device.

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