Number of increments

Assume temperature increments of condensation from the inlet temperature to the outlet. The increments should be smaller near the inlet as most of this heat load will be transferred at the higher temperature level. The number of increments is a function of the desired accuracy. However, as a rule, the minimum should be 4, with 6 or more being preferred. 

Because we are always in a hurry (so many samples, so little spectrometer time) we always try to acquire that little bit faster than we should. This is particularly true with 2-D acquisitions which can be very time-consuming. As discussed previously, we try to minimise the number of increments to save time. This gives rise to highly truncated data sets and poor resolution. This can be made to look a little prettier by adding a load of zeros to the experiment before Fourier transforming it. We call this (somewhat obviously) zero filling . Note that this doesn t add any information but it does make the result look nicer. 

The number of increments can be changed using the parameter ARRAY. The boundary conditions dictate the formulation of the first and last segments as follows Center of slab (segment ARRAY), dS/dX=0 and dP/dX=0 surface conditions (segment 0), P0 and S0. With the same parameter values, the results of example ENZSPLIT should be exactly the same as the steady-state of ENZDYN. 

The calculation accuracy can be increased by splitting the tube length into a number of increments and making the calculation of the pressure drop for each. 

In Example 10.2, the range of pressure in the supply tank is specified and a more convenient method of calculation is to split the pressure range into a number of increments. After calculating the mass flow rate, the mass remaining in the tank is determined from the pressure at the end of the increment and hence the required time may be determined. A small refinement is to base the flow rate calculation on the mean pressure in the increment rather than on that at the beginning. 

The number of increments taken shall directly influence the sampling accuracy provided the bulk material comprises of varying particle sizes. 

If the distribution is Gaussian or binomial, the minimum number of increments can be e tijated from... 

The proper setting for variographic analysis is a set of 60 representative increments (this is a minimnm requirement, 100 samples is always preferable if possible, the minimum number of increments ever snc-cessfnlly snpporting an interpretable variogram is 42), in order to cover well the specific process variations to be characterized. It is important to select a 0niin that is smaller than the most probable sampling frequency likely to be used in rontine process monitoring and QC. It will be the objective of the data analysis to... 

OPA orthogonal projection approach Q number of increments per sample... 

The range of doses and number of increments likely to be required in man... 

Situations may arise when the dose range that has to be studied is very wide and the number of increments required to cover the range is large. It may then be advisable to use successive cohorts of volunteers so that the first cohort might receive dose levels 1-4, the second dose levels 4-7 and so on. Note that each cohort is introduced at the top dose level received by the preceding cohort, the... 

As can be seen in these equations, depends on a number of factors. The properties of the population from which the object stems are described by a, and T,. The relevant property of the object is its size p, expressed in units Tx. The relevant properties of the sample are increment size g, the number of increments n and the distance between the increments, a. If the sample size is expressed as a fraction of the object, F, the relations between F, a and n are depicted in Fig. 7 and 8... 

The number of increments (e.g., the number of shovelfuls required to constitute the gross sample, which is usually 200 to 500 lb) must be established. 

For raw, dirty, or poorly cleaned coal, the minimum number of increments is 35. 

In summary, the precision of sampling improves with the size of each of the increments collected and with the number of increments included in a gross sample and manual sampling involves the principle of ideal sampling insofar as every particle in the entire mass to be sampled has an equal opportunity to be included in the sample. 

In car-top sampling, only the coal near the top surface has the potential to be included in the sample, thereby violating the basic tenet of obtaining a representative sample. Thus, the uncertainties regarding the accuracy of the results are increased and any conclusions drawn from the data are highly suspect. Therefore, if car-top sampling is a necessity, the increments must not be collected predominantly from any given location relative to the dimensions of the railcar. Furthermore, if the railcars vary substantially in size, the number of increments per car should be varied proportionately. 

Gross moisture sample sample representing one lot of coal and composed of a number of increments on which neither reduction nor division has been performed or a subsample for moisture testing taken. 

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