Quasi-static methods

Table 1.5 reviews the capabilities of the most common (quasi-)static methods (we excluded the very fast oscillating jet and pulsating bubble), obtaining dynamic information. Some of these are intrinsically dynamic in that the measurement requires the extension of an interface (drop weight, maximum bubble pressure), so that y(t) data can in principle be obtained when the rate of extension can be varied in a controlled fashion. Others are basically static (shapes of sessile or pendent drops and bubbles), but can be rendered dynamic by disequilibratlon. 

In studying the kinetics of spontaneous boiling-up of superheated water use was made of the method of measuring the lifetime (quasi-static method) and the method of pulse superheat of a liquid on a thin platinum wire (dynamic method). 

As the size of the metastable region and the number of relaxation times by all the signs increase, the use of quasi-static methods becomes unacceptable. It is probably for this reason in part that research into not fully stable states of complex systems (mixtures and thermally unstable fluids ) progresses very slowly. To solve the problem, we are developing the method of controlled pulse heating of a thin wire probe - resistance thermometer. 

At longer adsorption times a large variety of static and quasi-static methods exists, reaching into the time domain of hours and even days. 

Fig. 6.15. C-V characteristics taken using quasi-static methods for a series of devices with the same source and drain overlap, bnt different channel lengths. In depletion (toward the right part of the graph) the capacitance observed is only the overlap capacitance Cos + Cgd and is the same for all devices. In accnmulation the capacitance is Cgs + Cgd- -CoxWL, and the channel capacitance can be measnred from the difference.

Static and quasi-static methods of evaiuation of pair pressure... 

This paper has used the SLOPEAV module in the Geo Slope system software developed by the Canadian company, based on a slope stability analysis and calculation method which is recommended by the specification—Quasi static method to analyze and calculate the stability. Among all the methods, the M-P method is the strict solution which is recommended by slope specification. Therefore, M-P results are mainly adopted for the stability analysis (Zhang et al., 2008). The stability calculations have considered natural and earthquake circumstances, and used 0.10 g and 0.15 g, which are different seismic peak acceleration, to calculate in earthquake conditions (Chai et al., 2007). The calculate parameters has based on the integrated shear strength parameters. The results have been shown in figure 8 and figure 9. 

Measurement of Piezoelectric Constants by a Static (or quasi-static) Method... 

Usually, a ferroelectric thin film sample fabricated by the sol-gel method is coated on a substrate, which is much thicker than the film. The piezoelectric constant, 433, of the thin film sample can be measured by the static (or quasi-static) method and the electromechanical coupling factor 33 can be calculated from the known dielectric constant and the elastic coefficients 3. It is hard to measure a thin film/substrate system by a dynamic method, e.g., the transportation line method, because the vibrator is a thin film/substrate system and the major vibration is caused by the substrate, not by the film. 

Methods for Measuring the Pyroelectric Coefficient of Composites The most usual way to measure the pyroelectric coefficient is by the coavenlkmal quasi-static method [48,154,155]. Since tte polarizalioo P measure is surface charge density o QIA (Q denotes electric charge and A is the surface of the dielectric film), Eq. (25) can be rewritten as follows ... 

Unlike crystalline melting, the glass transition temperature is a relaxation transition. This means that it is dependent on the effective frequency of the measureirtent. This frequency is found by dynamic mechanical (DMA), dielectric relaxation, and pulsed nuclear magnetic methods. Quasi-static methods, such as dilatometry, differential scanning calorimetry (DSC), and thermomechanical analysis (TMA), show that the effective frequency depends on the rate of temperature scan. This is one of the reasons why the glass transition temperatures reported for various amorphous materials appear so diverse. 

J. Zhao et al. [5] measured the vapwr pressure data for nine binary systems containing water, methanol or ethanol with the ionic liquids l-methyl-3-methylimidazolium dimethylphosphate ([MMImJDMP), l-ethyl-3- methylimidazolium diethylphosphate ([EMImJDEP) and l-butyl-3-methylimidazo- Hum dibutylphosphate ([BMImJDBP) and one ternary system ethanol-water- [MMImJDMP at varying temperature and ionic liquid mass percent ranging from 10% to 70% by a quasi-static method. The vapor pressure data of the... 

Monte Carlo methods can be classified as static, quasi-static or dynamic. Static methods are those that generate a sequence of statistically independent samples from the desired probability distribution tt. Quasi-static methods are those that generate a sequence of statistically independent batches of samples from the desired probability distribution ir the correlations within a batch are often difficult to describe. Dynamic methods are those that generate a sequence of correlated samples from some stochastic process (usually a Markov process) having the desired probability distribution TT as its unique equilibrium distribution. 

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