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Improvements defined

The American Chemical Society s Committee on Environmental Improvement defines standardization as the process of determining the relationship between the measured signal and the amount of analyte. A method is considered standardized when the value of k in equation 5.1 or 5.2 is known. [Pg.106]

Clinical Trials In controlled clinical trials in patients with asthma, the onset of improvement in pulmonary function, as measured by maximum midexpiratory flow rate (MMEF), was within 30 minutes after a dose of albuterol tablets, with peak improvement occurring between 2 and 3 hours. In controlled clinical trials in which measurements were conducted for 6 hours, clinically significant improvement (defined as maintaining a 15% or more increase in forced expiratory volume in 1 second [FEVj] and a 20% or more increase in MMEF over baseline values) was observed in 60% of patients at 4 hours and in 40% at 6 hours. In other single-dose, controlled clinical trials, clinically significant improvement was observed in at least 40% of the patients at 8 hours. No decrease in the effectiveness of albuterol tablets was reported in patients who received long-term treatment with the drug in uncontrolled studies for periods up to 6 months. [Pg.60]

In Figure 12 is presented the calculated (a) and experimental (b) relative output energy improvement, defined as A = 100%, where and... [Pg.105]

This justifies all the work undertaken to arrive at fuel denitrification which, as is well known, is difficult and costly. Moreover, technological improvements can bring considerable progress to this field. That is the case with low NO burners developed at IFF. These consist of producing separated flame jets that enable lower combustion temperatures, local oxygen concentrations to be less high and a lowered fuel s nitrogen contribution to NOj. formation. In a well defined industrial installation, the burner said to be of the low NO type can attain a level of 350 mg/Nm, instead of the 600 mg/Nm with a conventional burner. [Pg.269]

The nature of these paraffins and their concentration in diesel fuel affect the three temperatures that characterize the cold behavior. The cloud point is the temperature at which crystals of paraffins appear when the temperature is lowered. The cold filter pluming point is defined as the temperature under which a suspension no ionger flows through a standard filter. Finally, the pour point is the temperature below which the diesel fuel no longer flows by simple gravity in a standard tube. These three temperatures are defined by regulations and the refiner has three types of additives to improve the quality of the diesel fuel of winter. [Pg.353]

At each phase of a project cost information is required to enable decisions to be taken. In the conceptual phase these estimates may be very approximate (e.g. + 35% accuracy), reflecting the degree of uncertainty regarding both reservoir development and surface options. As the project becomes better defined the accuracy of estimates should improve. [Pg.299]

The main goal of ultrasonic grain noise suppression in material flaw detection is to improve the perceptual possibilities of the operator to observe defect echoes. The suppression is defined as perceptually ideal when a received signal (or image) which contains echoes buried in noise is filtered to yield nonzero values only at the positions of the defect echoes. [Pg.89]

Flead and Silva used occupation numbers obtained from a periodic FIF density matrix for the substrate to define localized orbitals in the chemisorption region, which then defines a cluster subspace on which to carry out FIF calculations [181]. Contributions from the surroundings also only come from the bare slab, as in the Green s matrix approach. Increases in computational power and improvements in minimization teclmiques have made it easier to obtain the electronic properties of adsorbates by supercell slab teclmiques, leading to the Green s fiinction methods becommg less popular [182]. [Pg.2226]

In this paper we present a number of time integrators for various problems ranging from classical to quantum molecular dynamics. These integrators share some common features they are new, they are second-order accurate and time-reversible, they improve substantially over standard schemes in well-defined model situations — and none of them has been tested on real applications at the time of this writing. This last feature will hopefully change in the near future [20]. [Pg.421]

Once the quality of the dataset is defined, the next task is to improve it. Again, one has to remove outliers, find out and remove redundant objects (as they deliver no additional information), and finally, select the optimal subset of descriptors. [Pg.205]

The idea behind this approach is simple. First, we compose the characteristic vector from all the descriptors we can compute. Then, we define the maximum length of the optimal subset, i.e., the input vector we shall actually use during modeling. As is mentioned in Section 9.7, there is always some threshold beyond which an inaease in the dimensionality of the input vector decreases the predictive power of the model. Note that the correlation coefficient will always be improved with an increase in the input vector dimensionality. [Pg.218]

In recent decades, computer scientists have tried to provide computers with the ability to learn. This area of research was summarized under the umbrella term "machine learning . Today machine learning is defined as "the study of computer algorithms that improve automatically through experience [1]. [Pg.440]

If we define region 1 so that it overlaps with X and Y we may improve the sampling a obtain a more reliable value. This is shown in Figure 11.1. [Pg.581]

The catalytic vapor-phase oxidation of propylene is generally carried out in a fixed-bed multitube reactor at near atmospheric pressures and elevated temperatures (ca 350°C) molten salt is used for temperature control. Air is commonly used as the oxygen source and steam is added to suppress the formation of flammable gas mixtures. Operation can be single pass or a recycle stream may be employed. Recent interest has focused on improving process efficiency and minimizing process wastes by defining process improvements that use recycle of process gas streams and/or use of new reaction diluents (20-24). [Pg.123]

Nearly every chemical manufacturiag operation requites the use of separation processes to recover and purify the desired product. In most circumstances, the efficiency of the separation process has a significant impact on both the quality and the cost of the product (1). Liquid-phase adsorption has long been used for the removal of contaminants present at low concentrations in process streams. In most cases, the objective is to remove a specific feed component alternatively, the contaminants are not well defined, and the objective is the improvement of feed quality defined by color, taste, odor, and storage stability (2-5) (see Wastes, industrial Water, industrial watertreati nt). [Pg.291]


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See also in sourсe #XX -- [ Pg.150 ]




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