Factor noise

Severe corrosion, Rough tubing, Probe wear. Centring, Fill factor, Noise... 

A major part of Taguchi s philosophy centers around the separation of effects caused by noise factors and effects caused by control factors. Control factors are variables that are under the control of the experimenter flow rate, pH, concentration, reactor temperature, etc. In contrast, noise factors are variables that are not under the control of the experimenter ambient temperature, ambient humidity, identity of process operator (Joe or Jane), source of raw material, etc. Control factors are sometimes called process factors noise factors are sometimes called environmental factors. 

It was discussed above that two types of factors can influence our process or system controlled factors design factors in Taguchi s terminology) and uncontrolled factors noise factors. The latter are inherent to the experimentation and can only be estimated by replication of runs. If the variability between replications is too large, any conclusion drawn from our study may have no meaning at all. Further, their variability can be as important as the mean of the replicates. Noise factors must be identified properly and, if possible, simulated in our experimentation. Sometimes noise factors are actually uncontrolled and, in such a case, we must be able to simulate them by means of some alternative parameter controlled during the experiments. For instance, temperature inside an oven can be a noise factor, but we can measure it at different locations, and accordingly, the effect of temperature inside is simulated by a location factor. 

Other Stress Factors. Noise has been shown to affect the rate of metabolism of 2-napthylamine, causing a slight increase in the rat. This increase is additive with that caused by cold stress. 

Proc. Algorithm Bunching Factor Noise Threshold Area Threshold ... 

Sanotskij IV, Grodetskaya MS, Gasenian GA, et al. 1984. The study of the combined effect of carbon disulfide and other harmful environmental factors (noise, alcohol, stress) on cardiovascular system. Combined effects of occupational exposures. Proceedings of the Fourth Finnish-Soviet Joint Symposium, Institute of Occupational Health, Helsinki, Finland. 29-41. 

As a supplement to R2.2.1766-03, specific recommendations are planned on methods and criteria assessment (scales, models, etc) of workers health (morbidity, mortality, etc), workplace factors (noise, vibration, dust, chemicals, etc), work load (physical load nervous tension), and reproductive health risk assessment. Relevant data have been published in handbook on occupational risk (Izmerov Denisov, 2003). 

Occupational diseases that affect the health of workers, to cause premature workers lose the ability to work the main factors. Mine occupational hazards in dust (coal dust, rock dust, cement dust, etc.), chemicals (nitrogen oxides, carbon oxides, sulfur dioxide, hydrogen sulfide, etc.) and physical factors (noise, vibration, thermal radiation, high temperature, etc.) three categories. Which is the most serious to dust hazards caused by pneumoconiosis. 2009,14,495 cases of pneumoconiosis new cases, the CWP and sand lung accounted for 91.89%. The incidence of pneumoconiosis shorten the length of service, the mass of pneumoconiosis... 

Noise. Sound emissions which amount to a molestation or pose a danger to man are perceived as noise and are regarded as negative environmental factors. Noise is a mixture of pressure waves of frequencies from between 18 and 20,000 Hz. 

It was discussed above that two types of factor can influence our process or system controlled factors ( design factors in Taguchi s terminology) and uncontrolled factors ( noise factors ). The latter are inherent to the... 

Quality is best achieved by minimising the deviation from the target. The product should be designed in such a way that it is immune to uncontrollable environmental factors (noise factors). 

There is some uncertainty connected with testing techniques, errors of characteristic measurements, and influence of fectors that carmot be taken into account for building up a model. As these factors cannot be evaluated a priori and their combination can bring unpredictable influence on the testing results it is possible to represent them as additional noise action [4], Such an approach allows to describe the material and testing as a united model — dynamic mathematical model. 

Figure 1. Dynamic model of testing of the material as a black box , where IN - loads and actions OUT - response of the material as measuring characteristics N - noise (combination of uncertain factors) ...

In order to maximize the excitation, precautions have to be taken to avoid cross-talk between excitation and signal. Therefore differential probes are commonly used with a SQUID system Nevertheless, for the discussed defects the SQUID system has a lower excitation field by a factor of about 100 compared with the commereial system This we must keep in mind, when we compare measured signal to noise ratios. There is a potential to improve for small defeets, when eross-talk is managed very well. 

It can be observed from the Figure 1 that the sensitivity of I.I. system is quite low at lower thicknesses and improves as the thicknesses increase. Further the sensitivity is low in case of as observed images compared to processed images. This can be attributed to the quantum fluctuations in the number of photons received and also to the electronic and screen noise. Integration of the images reduces this noise by a factor of N where N is the number of frames. Another observation of interest from the experiment was that if the orientation of the wires was horizontal there was a decrease in the observed sensitivity. It can be observed from the contrast response curves that the response for defect detection is better in magnified modes compared to normal mode of the II tube. Further, it can be observed that the vertical resolution is better compared to horizontal which is in line with prediction by the sensitivity curves. 

Fig.5 shows the noise influence on CCF for both types of pulses and different b values. This influence is weak, especially for q(t) type of signals. For s(t) signals growth of 2-factor critically increases the signal to noise ratio. For q(t) signals this effect is much weaker and depends on quantity of periods in pulses. 

After the signal emerges from the lock-m amplifier it still contains a considerable amount of noise. Most of the noise contributions to the signal can be eliminated by passing the signal tlirough a low-pass filter. The filter tune constant is a measure of the cutoff frequency of the filter. If accurate linewidth and g-factor... 

The pyrolysis of CR NH (<1 mbar) was perfomied at 1.3 atm in Ar, spectroscopically monitoring the concentration of NH2 radicals behind the reflected shock wave as a fiinction of time. The interesting aspect of this experiment was the combination of a shock-tube experiment with the particularly sensitive detection of the NH2 radicals by frequency-modulated, laser-absorption spectroscopy [ ]. Compared with conventional narrow-bandwidth laser-absorption detection the signal-to-noise ratio could be increased by a factor of 20, with correspondingly more accurate values for the rate constant k T). 

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