Estimation of errors at the calibration of spectral data at the Irbene RT-32 radio telescope

2020 ◽  
pp. 23-38
Author(s):  
O ANTYUFEYEV ◽  
M BLEIDERS ◽  
O PATOKA ◽  
V BEZRUKOVS ◽  
A ABERFELDS ◽  
...  
Keyword(s):  
Standard Deviation ◽  
Spectral Line ◽  
Spectral Data ◽  
Radio Telescope ◽  
Antenna Temperature ◽  
Oscillator Frequency ◽  
System Temperature ◽  
The Stability

We analyze calibration errors that occur during the single-dish observations at the Irbene RT-32 radio telescope when calibration is done using noise diode. Only frequency switched mode of spectral line observations is considered. The purpose of the article is to find possible values of noise diode temperature Tcal and period of switching oscillator frequency 2tq. For this, we have analyzed the formula for calculating the antenna temperature of the source. It is shown that noise diode temperature affects the standard deviation of source antenna temperature σTs and the error of source antenna temperature δTs caused by instability of system temperature. tq affects the stability of the characteristics of the receiving system. In this article, the dependencies between Tcal, tq, σTs and δTs were found and analyzed. Based on these dependencies, possible values of Tcal and tq are found.

First Results Using a K-Band Maser Receiver on the Parkes 64-m Radio Telescope

1982 ◽  
Vol 4 (4) ◽  
pp. 451-453
Author(s):  
R. A. Batchelor ◽  
J. L. Caswell ◽  
J. R. Forster ◽  
K. J. Wellington
Keyword(s):  
Flux Density ◽  
Radio Telescope ◽  
Total System ◽  
Astronomical Observations ◽  
Antenna Temperature ◽  
First Results ◽  
System Temperature ◽  
24 Ghz ◽  
Csiro Division ◽  
K Band

A new maser receiver, operating between 20 and 24 GHz and constructed by the radiometer group at the CSIRO Division of Radiophysics, was first scheduled for astronomical observations in December 1981. In good observing conditions the system temperature was as low as 60 K. In conjunction with the versatility of the 1024-channel correlator and the large collecting area of the Parkes telescope (the central 37 m illuminated at 22 GHz yields a ratio of flux density to antenna temperature of 9∼ Jy K-1) the total system is a very powerful new tool. Here we report some observations of naturally occuring celestial H2O masers which we have studied with this system.

Effect of test parameters on the stability of fabric shape retention indexes increase recovery testing

2021 ◽  
pp. 004051752110242
Author(s):  
Qianhui Tang ◽  
Lei Wang ◽  
Weidong Gao ◽  
Ruru Pan
Keyword(s):  
Standard Deviation ◽  
Sample Size ◽  
Orthogonal Test ◽  
Test Scheme ◽  
Optimal Test ◽  
Pressure Time ◽  
Test Parameters ◽  
Shape Retention ◽  
The Stability ◽  
Retention Indexes

Fabric shape retention is a crucial property that impacts the durability and usability of fabric and which needs a convenient and accurate evaluation method. In the previous research, the automated crease recovery testing method was used to obtain fabric crease recovery information and evaluate the property of shape retention. Based on the previous research, an orthogonal test method was adopted to investigate the effect of different test parameters on the stability of shape retention detection in this paper. First, three factors, that of sample size, pressure, and pressure time, and three different levels of each factor were determined by the L9(34) orthogonal test table. Next, the fabric shape retention indexes were detected by nine different test schemes, and the comprehensive score of shape retention index standard deviation was obtained as the evaluation criterion of the orthogonal test results. Finally, the optimal test scheme was determined by visual analysis and variance analysis. The results show that the sample size has a certain effect on the stability of shape retention indexes, while the pressure time and the pressure have no significant influence. The optimal test scheme is that the sample size is 30 cm × 30 cm, the pressure time is 60 s, and the pressure is 40 N. The test result measured by the optimal test parameters reveals excellent stability when the vertex angle standard deviation is 2.0°, the height standard deviation is 0.06 cm, and the shape retention area standard deviation is 0.16 cm2. This paper provides an experimental basis for improving the accuracy of fabric shape retention evaluation method.

Molecular Line Observations at Parkes with a 3 GHz Maser

1979 ◽  
Vol 3 (5) ◽  
pp. 321-323 ◽  
Author(s):  
B. Höglund ◽  
J. B. Whiteoak ◽  
F. F. Gardner
Keyword(s):  
Spectral Line ◽  
Radio Telescope ◽  
Ground State ◽  
State Transitions ◽  
Space Observatory ◽  
Molecular Line ◽  
System Sensitivity ◽  
Onsala Space Observatory

A 3 GHz maser from the Onsala Space Observatory, Sweden, is currently at Parkes on a long-term loan basis. So far, it has been used on the 64-m radio telescope for a two-week period of spectral-line observations in February 1979, providing a system sensitivity far superior to that previously available at the same frequency. The observed lines were the ground-state transitions of CH at 3264, 3335 and 3349 MHz, the 211 – 212 transition of H2CS at 3139 MHz, and the 211-212 transition of CH3CHO at 3195 MHz.

scholarly journals Microwave treatment of rice

2013 ◽  
Vol 19 (No. 2) ◽  
pp. 62-66 ◽  
Author(s):  
J. Kaasová ◽  
P. Kadlec ◽  
Z. Bubník ◽  
V. Pour
Keyword(s):  
Microwave Heating ◽  
Starch Content ◽  
Initial Moisture Content ◽  
Microwave Treatment ◽  
Drying Time ◽  
Treated Sample ◽  
System Temperature ◽  
Rice Drying ◽  
The Stability ◽  
Total Starch

The effect of microwave treatment on wet rice was studied. Power output used was 90, 160, 350 or 500 W; final heating temperatures were 40, 60 and 80°C; initial moisture content of rice was 11, 21 or 30%. Temperature of treated sample during microwave heating was measured by means of NoEMI fiber-optic temperature system. Temperature of rice gelatinization, expressed as alkali spreading values and total starch content, was used to evaluate the influence of microwave heating on physicochemical properties of rice. Drying time reduction and the stability of total starch content during microwave treatment of rice makes it possible to recommend the combination of microwave and conventional rice drying for further use.

Spectral-Line Observations of NGC 5128 at Centimetre Wavelengths

1976 ◽  
Vol 3 (1) ◽  
pp. 63-65 ◽  
Author(s):  
F. F. Gardner ◽  
J.B. Whiteoak
Keyword(s):  
Spectral Line ◽  
Radio Source ◽  
Radio Telescope ◽  
Forthcoming Paper ◽  
Co Observations

One of the unusual features of the lenticular galaxy NGC 5128 is the presence of HI absorption (Roberts 1970; Whiteoak and Gardner 1971) and H2CO absorption (Gardner and Whiteoak 1976) against the radio source located near the nucleus. Using the Parkes 64-m radio telescope we have made HI and H2CO observations with improved resolution, and have also detected OH absorption in this galaxy. For the OH and H2CO observations, the equipment and observing procedure have already been described (e.g. Whiteoak and Gardner 1973; Gardner and Whiteoak 1976); for the HI observations they will be described in a forthcoming paper (Whiteoak and Gardner, to be submitted to Aust. J. Phys.).

Uncertainty Quantification and Stochastic Variations of Renewable Fuels

2015 ◽  
Author(s):  
F. Montomoli ◽  
M. Insinna ◽  
A. Cappelletti ◽  
S. Salvadori
Keyword(s):  
Standard Deviation ◽  
Temperature Distribution ◽  
Combustion Chamber ◽  
Uncertainty Quantification ◽  
Mean Value ◽  
Maximum Temperature ◽  
Test Case ◽  
Renewable Fuels ◽  
Stochastic Variation ◽  
The Stability

Renewable fuels have been successfully used in gas turbine combustion chambers and the layout of the chamber does not require major interventions if the composition is known. However, the variation in the composition in renewable fuels is higher than in fossil ones and it is stochastic. In principle, this variation affects the stability of the combustion, the emissions and the temperature distribution. The combustion chamber tested in this work has been designed to reproduce the temperature distribution of MT1 test case and modelled using reactive CFD simulations. The fuel is an ideal natural gas with a random mix of methane and hydrogen. In order to account the stochastic variation of the fuel composition, a probabilistic analysis is carried out with two sampling methods: a Monte Carlo simulation with meta-models and a Probabilistic Collocation Method. The two methodologies show similar results in terms of mean value and standard deviation. The paper proves that is possible to predict the mean value of temperature and emissions in a modern chamber and their associated standard deviation by applying an uncertainty quantification methodology. One of the major drawbacks of the composition change is the maximum temperature variation at the exit that can reduce the life of the downstream turbine. The variation in the emissions seems less important and all the major differences in the composition are mixed out before the combustion chamber exit.

scholarly journals Sample Entropy-Based Approach to Evaluate the Stability of Double-Wire Pulsed MIG Welding

2014 ◽  
Vol 2014 ◽  
pp. 1-8 ◽  
Author(s):  
Ping Yao ◽  
JiaXiang Xue ◽  
Kang Zhou ◽  
XiaoJun Wang
Keyword(s):  
Standard Deviation ◽  
Pulse Width ◽  
Quantitative Method ◽  
Orthogonal Experiment ◽  
Welding Current ◽  
Sample Entropy ◽  
Mig Welding ◽  
Base Current ◽  
The Stability ◽  
Three Factor

According to the sample entropy, this paper deals with a quantitative method to evaluate the current stability in double-wire pulsed MIG welding. Firstly, the sample entropy of current signals with different stability but the same parameters is calculated. The results show that the more stable the current, the smaller the value and the standard deviation of sample entropy. Secondly, four parameters, which are pulse width, peak current, base current, and frequency, are selected for four-level three-factor orthogonal experiment. The calculation and analysis of desired signals indicate that sample entropy values are affected by welding current parameters. Then, a quantitative method based on sample entropy is proposed. The experiment results show that the method can preferably quantify the welding current stability.

Robust Analysis of a Wireless Bistable Micro-Actuator

2012 ◽  
Author(s):  
Syed Sajid Hussain Zaidi ◽  
Zohra Cherfi-Boulanger ◽  
Nassim Boudaoud ◽  
Philippe Pouille ◽  
Frédéric Lamarque
Keyword(s):  
Standard Deviation ◽  
Power Supply ◽  
Switching Time ◽  
Total Duration ◽  
Optical Power ◽  
Transient Regime ◽  
Cycle Number ◽  
Micro Actuator ◽  
Micro Actuators ◽  
The Stability

Nowadays, the integration of micro-actuators in the micro-systems poses a significant problem due to the complex designs as well as due to the contact power supply systems (e.g., via micro-batteries or via wires). A way to overcome this problem is to provide remote power supply and control to the bistable micro-actuators. It is mainly done by RF (radio-frequency) or optical means. As a consequence, the stability of the two positions of this kind of micro-actuators and the switching time evolution between them have to be studied to determine the robustness of the contactless bistable micro-actuators. In this work, these system parameters were analysed by the ANOVA (Analysis Of Variance) method during a longlife test for 8 different configurations (Design of Experiments) of bistable micro-actuators controlled by laser. Transient and permanent regimes were observed for the stability of the positions, for the standard deviation around the positions and for the switching time as well. In each case, the transient regime represented only 3% of the total duration of the longlife test. A very good stabilisation was observed in the permanent regime whereas a decrease of the stroke was observed in the transient regime. As a consequence, during this regime, the switching time was reduced compared with the regular values (few seconds, optical power dependent). In the permanent regime, a progressive increase of this factor was noted that indicated the progressive fatigue of the bistable micro-actuator. A second indicator of the micro-actuator fatigue was given by the increase of the standard deviation of the stable position after cycle number 9000. Above this point, the micro-actuator was vibrating during the functioning even if the stability remained acceptable.

The resonant valley suppression of a hydraulic shaking table by using adaptive spectral line enhancer

2018 ◽  
Vol 232 (10) ◽  
pp. 1379-1388
Author(s):  
Tao Wang ◽  
Jinchun Song
Keyword(s):  
Spectral Line ◽  
Coupling Effect ◽  
Resonance Effect ◽  
Shaking Table ◽  
Resonance Phenomenon ◽  
Resonant System ◽  
Stability Range ◽  
Elastic Load ◽  
Hydraulic Servo ◽  
The Stability

As an electro-hydraulic servo shaking table takes on an elastic load in a vibration test of a 2-mass dynamic system, a mutual coupling effect is exerted between the shaking table and the specimen, which will form a resonant system to weaken the dynamic characteristics of the system. As required by the system bandwidth, the resonant system contains a resonance valley and a resonance peak, and its amplitude commonly surmounts the stability range of the system’s acceleration amplitude. In this article, the resonance phenomenon is analyzed, and the structure and the parameters of the three-state controller are designed on the basis of a pole assignment system. The adaptive spectral line enhancer is adopted to suppress the resonant valley, and the power spectrum is analyzed to experimentally verify that it exerts an anti-resonance effect.

scholarly journals The extent of achieving the goals of civic education in the light of the concept of globalization in the curriculum of the civic and national education of high elementary schools from Aqaba teacher’s perspective

2021 ◽  
Vol 10 (1) ◽  
pp. 17
Author(s):  
Doha I. AL- Tarawneh ◽  
Jehan Hashim AL-Safasfeh ◽  
Ekhlas M. Al.Edi
Keyword(s):  
Elementary Schools ◽  
Standard Deviation ◽  
Civic Education ◽  
Arithmetic Average ◽  
National Education ◽  
The Social ◽  
Study Population ◽  
Standard Deviations ◽  
The Stability ◽  
Teacher's Perspective

The study aimed at revealing the extent of achieving the goals of civic education in the light of the concept of globalizationin the curriculum of the civic and national education of high elementary schools from Aqaba teacher’s perspective.  The study population consists of all the teachers of the social studies in elementary schools at Aqaba Governorate for the year (2019-2020). It consists of 49 teachers distributed in 17 schools. The study tried to answer the following questions: To what degree the goals of civic education in the light of the concept of globalization in the curriculum of the civic and national education from Aqaba teacher’s perspective can be achieved? Are there any statistical difference in the teacher’s evaluations to achieve thecurriculum of the civic and national education based on gender and level of education? The study tools were a test and a questioner that measures the teachers’ view of the extent of achieving the goals of civic education in the light of the concept of globalization. Therefore it was divided into two parts one pertaining the citizenship values and the other one pertaining the goals of globalization. The researcher got the arithmetic averages and the standard deviations for each paragraph and for each field of the study. The stability coefficients of the study were measured individually in addition to the questioner coefficient of stability as a whole which was (0.78). The globalization stability coefficient was (0.78) and the civic education was (0.896) all of which are high and accepted stability coefficients. The arithmetic averages and the standard deviations were measured for the two parts of the study. It was noticed that the civic education got the lowest arithmetic average (3.01) and a standard deviation (0.91). As for the second part namely the globalization that got the highest arithmetic average (3.29) and a standard deviation (1.16). The researcher believes that the awareness of civic education and the goals of globalization are very important and should be included in the curriculum. Both come in accordance with the study conclusion.

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