Improve Signal-to-Noise Ratio

A corresponding composite probe with the same frequency and crystal size, however, detects the test flaw much better the echo has a 12 dB higher amplitude (see Fig. 4) and in addition, the noise level is much lower, resulting in an improved signal to noise ratio. This effect is especially observed at high sound attenuation. However, in materials with low attenuation or in case of shorter sound paths the standard probe yields a comparable good signal to noise ratio. 

There is an improved signal-to-noise ratio in the raw data. This can be seen in the Ex N E) form of data in Figure 3-... 

The fourth-order coherent Raman spectrum of a liquid surface was observed by Fujiyoshi et al. [28]. The same authors later reported a spectrum with an improved signal-to-noise ratio and different angle of incidence [27]. A water solution of oxazine 170 dye was placed in air and irradiated with light pulses. The SH generation at the oxazine solution was extensively studied by Steinhurst and Owrutsky [24]. The pump and probe wavelength was tuned at 630 nm to be resonant with the one-photon electronic transition of the dye. The probability of the Raman transition to generate the vibrational coherence is enhanced by the resonance. The efficiency of SH generation is also enhanced. 

As said before, there are two main applications of Fourier transforms the enhancement of signals and the restoration of the deterministic part of a signal. Signal enhancement is an operation for the reduction of the noise leading to an improved signal-to-noise ratio. By signal restoration deformations of the signal introduced by imperfections in the measurement device are corrected. These two operations can be executed in both domains, the time and frequency domain. 

The analytical performance of Prussian blue-modified electrodes in hydrogen peroxide detection were investigated in a flow-injection system equipped with a wall-jet cell. Nano-structured Prussian blue-modified electrodes demonstrate a significantly decreased background, which results in improved signal-to-noise ratio. 

Probably the first instrument designed for reflectance studies was that described by Nutting [8], and improved by Taylor [9]. Since that time, a large number of instruments have been proposed, and numerous modifications suggested to continually improve signal-to-noise ratios [1,2]. 

In conclusion, CL ISH has proved more sensitive than ISH followed by colorimetric detection and can be as sensitive as ISH using radioactive labels [31, 32, 64, 65], When compared with fluorometric detection, CL showed an improved signal-to-noise ratio, thus a higher specific detectability furthermore, once standardized, it provided more precise and accurate quantitative results. 

Equation (7.1) suggests that larger values of 7um may be obtained by rotating the RDE at ever faster speeds. Is it valid to suppose that a faster CO will always lead to an improved signal-to-noise ratio ... 

Biological samples, which are often available in limited amounts, can be separated and detected with a drastically improved signal-to-noise ratio, since the volumetric band-broadening (dilution) is much smaller on a capillary column. Smaller columns also require less solvent which is an... 

Wang et al. [34] have introduced a new heated mercury film electrode based on a screen printed carbon substrate. It was used in anodic stripping and exhibited a significantly improved signal-to-noise ratio. A directly heated mercury film electrode for anodic stripping voltammetry has been described by Jasinski [35]. Different factors influencing the quality of analytical determination have been investigated. Renewed mercury electrodes and examples of their various applications have been reviewed in Ref. 36. Lovric and Scholz [37] have discussed the conditions... 

When an improved signal-to-noise ratio is required, Eq. (1) becomes... 

Better control of the cantilever oscillation in liquid environment can be achieved when the cantilever is oscillated directly by an external force. This idea was implemented by the so-called Magnetic-Alternative-Current Mode (MAC Mode) [194]. A magnetic cantilever is driven by an external magnetic field which is generated by a solenoid placed beneath the sample. The direct excitation of the cantilever avoids unwanted resonance s from the cantilever holder, the fluid body, and the sample itself. Furthermore, the improved signal-to-noise ratio allows smaller oscillation amplitudes and set point ratios Asp/Af closer to 1. Both factors result in a significant reduction in the energy deposited into the sample,... 

Computers. - Gone are the days when the computer merely added spectra together to improve signal-to-noise ratios. Modern dedicated computers, once they have been set up by the operator, completely control the n.m.r. experiment, including all manner of pulse sequences, delay times, Fourier transformations, integrations, data retrieval, and data manipulation even automatic sample changing is becoming available. Possibly the best sources of the latest information on the capabilities of typical n.m.r. computer systems are the major instrument manufacturers. 

An improved signal-to-noise ratio in the topographic analysis of coenzyme fluorescence transients will mean enhanced accuracy in the determination of metabolic rate laws (18,19,20,... 

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