Effectiveness, general definition

Elevated Flares See Flares for a general definition. The elevated flare, by the use of steam injection and effective tip design, operates as a smokeless combustion device. Flaring generally is of low luminosity up to about 20 % of maximum flaring load. Steam injection tends to introduce a source of noise to the operation, and a compromise between smoke elimination and noise is usually necessary. When adequately elevated (by means of a stack) this type of flare displays the best dispersion characteristics for malodorous and toxic combustion products. Visual and noise pollution often creates nuisance problems. Capital and operating costs tend to be high, and an appreciable plant area can be rendered unavailable for plant operations and equipment because of excessive radiant heat. 

You may not find observing the process gain matrix satisfactory. That takes us to the relative gain array (RGA), which can provide for a more quantitative assessment of the effect of changing a manipulated variable on different controlled variables. We start with the blending problem before coming back to the general definition. 

There are several ways to define efficiency. One general definition says that energy efficiency is the ability to produce a desired effect with minimum energy expenditure. For example, suppose that you want to bake a potato. You can use a microwave oven or a conventional oven. 

As no international consensus has been achieved in the OECD/IPCS project (OECD 2003a) in order to differentiate between dose (concentration)-response (effect) relationship and because it in reality is difficult to understand the subtle differences in the different terms as defined in the OECD/IPCS project, the broader and more general definition provided in the TGD (EC 2003) will be used in this book, and will generally be referred to as dose-response. Consequently, the term dose will, in this book, generally mean both dose and exposure concentration unless otherwise stated. 

A general definition of the term acute toxicity is The adverse effects occurring within a given time, following a single exposure to a substance. The term usually excludes local irritant or corrosive effects arising from a single application of a substance to the skin or eye (Section 4.5) (EC 2003). 

GENERAL DEFINITIONS. Effective use of statistical principles requires a clear understanding of certain fundamental terms. 

Let us give the general definition of chemical induction, which reflects its specific features. At chemical induction, chemical reaction spontaneously proceeding in the system performs the effective work for another, non-spontaneous chemical reaction in the same system to proceed, which may not run without the first one. 

The term piezoelectric nonlinearity is used here to describe relationship between mechanical and electrical fields (charge density D vs. stress a, strain x vs. electric field E) in which the proportionality constant d, is dependent on the driving field, Figure 13.1. Thus, for the direct piezoelectric effect one may write D = d(a)a and for the converse effect x = d(E)E. Similar relationships may be defined for other piezoelectric coefficients (g, h, and e) and combination of electro-mechanical variables. The piezoelectric nonlinearity is usually accompanied by the electro-mechanical (D vs. a or x vs. E) hysteresis, as shown in Figure 13.2. By hysteresis we shall simply mean, in the first approximation, that there is a phase lag between the driving field and the response. This phase lag may be accompanied by complex nonlinear processes leading to a more general definition of the hysteresis [2],... 

For rather general kinetics the effectiveness factor definition can be approximated as... 

In the operator L, the first term represents convection and the second diffusion. Equation (44) therefore describes a balance of convective, diffusive, and reactive effects. Such balances are very common in combustion and often are employed as points of departure in theories that do not begin with derivations of conservation equations. If the steady-flow approximation is relaxed, then an additional term, d(p(x)/dt, appears in L this term represents accumulation of thermal energy or chemical species. For species conservation, equations (48) and (49) may be derived with this generalized definition of L, in the absence of the assumptions of low-speed flow and of a Lewis... 

A more general definition of magnetization-transfer efficiency e, , that includes only coherent effects and that is independent of structural or motional properties of a specific sample can be defined based on the idealized transfer function Lfir) ... 

It was confirmed that the generalized definition of the effectiveness ffictor given in a previous paper [1] is valid for any type of kinetics and multiple deactivation mechanisms. 

The only advantage of the effective diffusivity definitions is their simplicity in computation no matrix functions need be evaluated. The primary disadvantage of the use of D- is that these parameters are not, in general, system properties except for the limiting cases noted in Chapter 6. 

Even when is low, the center and surface temperatures may differ appreciably, because catalyst pellets have low thermal conductivities (Sec. 11-5). The combined effect of mass and heat transfer on can still be represented by the general definition of the effectiveness factor, according to Eq. (11-41). Hence Eq. (11-42) may be used to find r, provided rj is the nonisothermal effectiveness factor. The nonisothermal 17 may be evaluated in the same way as the isothermal 77, except that an energy balance must be combined with the mass balance. 

A general definition of clinical trial , is any kind of study designed to establish the effects of a particular therapeutic intervention. 

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