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Accepted Definition

The broad intent of environmental ergonomics is to create prevailing ambient conditions that are comfortable, acceptable and do not compromise work performance or worker health (Hedge, 2005a). The relevant standard, BS/EN/ISO 11064-6 2005 (Ergonomic Design of Control Centers. Part 6. Environmental Requirements for Control Centers), states that factors such as lighting, humidity, temperature, vibration, noise, and aesthetics must be addressed, because poor environments can seriously affect operator performance. [Pg.307]


We may also define a free energy of mixing [240]. The alternative (and equally acceptable) definition of G given in Eq. 111-87 is... [Pg.140]

There is no official or universally accepted definition of what constitutes a "microemulsion." In fact, for several years, some leading scientists in microemulsion research considered the term to be an unnecessary and even an unfortunate one. Nevertheless (Table 1), during the years from about 1975 to 1980 the word ascended from obscurity to ubiquity. By the end of 1996 there were 13 widely available Knglish-language books (1 9) with the word "Microemulsion" in their tides (10). About 70 more books on surfactants are in print, of which those on industrial appHcations (9,11—18), and environmental effects (19—21) are of particular interest here. [Pg.147]

Plasma can be broadly defined as a state of matter in which a significant number of the atoms and/or molecules are electrically charged or ionized. The generally accepted definition is limited to situations whereia the numbers of negative and positive charges are equal, and thus the overall charge of the plasma is neutral. This limitation on charge leaves a fairly extensive subject area. The vast majority of matter ia the universe exists ia the plasma state. Interstellar space, interplanetary space, and even the stars themselves are plasmas. [Pg.106]

There are no universally accepted definitions of substitute dairy foods, which are referred to as imitations, simulates, substitutes, analogues, and mimics and are associated with terms such as filled, nondairy, vegetable nondairy, and artificial milk, cheese, etc. The term nondairy has been used indiscriminately to describe both imitation dairy products and products legally defined as not being imitation dairy products. Dairy substitutes can be divided into three types those in which an animal or vegetable fat has been substituted for milk fat those that contain a milk component, eg, casein [9000-71-9] or whey protein and those that contain no milk components (see Milk and milkproducts). The first two types make up most of the substitute dairy products. [Pg.438]

This type of bag-cleaning method is a fundamental characteristic of this type of collector. Terminology in the fabric filter field is not totally consistent or comprehensive. Table 13.2 presents acceptable definitions for common fabric filter terminology. [Pg.1233]

The first example of homogeneous transition metal catalysis in an ionic liquid was the platinum-catalyzed hydroformylation of ethene in tetraethylammonium trichlorostannate (mp. 78 °C), described by Parshall in 1972 (Scheme 5.2-1, a)) [1]. In 1987, Knifton reported the ruthenium- and cobalt-catalyzed hydroformylation of internal and terminal alkenes in molten [Bu4P]Br, a salt that falls under the now accepted definition for an ionic liquid (see Scheme 5.2-1, b)) [2]. The first applications of room-temperature ionic liquids in homogeneous transition metal catalysis were described in 1990 by Chauvin et al. and by Wilkes et ak. Wilkes et al. used weekly acidic chloroaluminate melts and studied ethylene polymerization in them with Ziegler-Natta catalysts (Scheme 5.2-1, c)) [3]. Chauvin s group dissolved nickel catalysts in weakly acidic chloroaluminate melts and investigated the resulting ionic catalyst solutions for the dimerization of propene (Scheme 5.2-1, d)) [4]. [Pg.214]

Dissipative systems whether described as continuous flows or Poincare maps are characterized by the presence of some sort of internal friction that tends to contract phase space volume elements. They are roughly analogous to irreversible CA systems. Contraction in phase space allows such systems to approach a subset of the phase space, C P, called an attractor, as t — oo. Although there is no universally accepted definition of an attractor, it is intuitively reasonable to demand that it satisfy the following three properties ([ruelle71], [eckmanSl]) ... [Pg.170]

The detection limit is another value which is often quoted, and this may be defined in a variety of ways. The most widely accepted definition is that the detection limit is the smallest concentration of a solution of an element that can be detected with 95 per cent certainty. This is the quantity of the element that gives a reading equal to twice the standard deviation of a series of at least ten determinations taken with solutions of concentrations which are close to the level of the blank. [Pg.804]

The overall objective of clinical trials is to establish a drug therapy that is safe and effective in humans, to the extent that the risk-benefit relationship is acceptable. The ICH process has developed an internationally accepted definition of a clinical trial as Any investigation in human subjects intended to discover or verify the clinical, pharmacological and/or other pharmacodynamic effects of one or more investigational medicinal product(s), and/or to identify any adverse reactions to one or more investigational medicinal product(s) and/or to study absorption, distribution, metabolism and excretion of one or more investigational medicinal product(s) with the object of ascertaining its (their) safety and/or efficacy. ... [Pg.73]

There are no universally accepted definitions of bulk, fine, and specialty chemicals, nor are these classifications based on any intrinsic properties. For example, a substance that is currently viewed as a bulk chemical may well have been classified as a fine chemical at an earlier stage in its development. [Pg.15]

Where is the dividing line between bulk and fine chemicals Here again there is no universally accepted definition. Nonetheless, a useful definition of a fine chemical is one with a price of more than 10 US dollars/kg and a volume of less than 10,000 tons per annum. The latter is rather a large volume for most fine chemicals, e.g. most pharmaceutical intermediates are produced in quantities of less than 100 tons per annum. In practice, the type of technology used is probably more dictated by volume than by product application. [Pg.16]

In a widely accepted definition, an analytical method can be defined as the series of procedures from receipt of a sample to the production of the final result. Often, not all procedures can be validated in an adequate way. However, even in such cases, where all procedures of a method are validated, the performance characteristics obtained do not reflect all sources of error. In a recent paper,the complete ladder of errors is described in the following way ... [Pg.130]

There is no generally accepted definition of what can be considered toxic and non-toxic. [Pg.362]

Sidney Altman discovered this property of RNA in the course of studies on precursor transfer RNA. It was realized that the catalytic properties of RNA are not exactly the same as those of protein enzymes, since the ribozyme is itself active and thus undergoes change during the catalytic reaction. This does not correspond to the generally accepted definition of an enzyme. Later studies, however, showed that some ribozymes are capable of acting catalytically at other RNA molecules. The ribozymes remain completely unchanged in this process, and thus fulfil the definition of a real enzyme. [Pg.163]

The term information often comes up in discussions of biogenesis, so a brief survey of its meaning is called for. Just as with the problem of the definition of the term life , there seems to be no generally accepted definition of the term information . The state of the physical world can be described in terms of three basic quantities ... [Pg.215]

According to Stuart A. Kauffman (1991) there is no generally accepted definition for the term complexity . However, there is consensus on certain properties of complex systems. One of these is deterministic chaos, which we have already mentioned. An ordered, non-linear dynamic system can undergo conversion to a chaotic state when slight, hardly noticeable perturbations act on it. Even very small differences in the initial conditions of complex systems can lead to great differences in the development of the system. Thus, the theory of complex systems no longer uses the well-known cause and effect principle. [Pg.244]

There is widespread indiscriminate use of, and thus confusion about the terms pharmacogenetics and pharmacogenomics . While no universally accepted definition exists, there is emerging consensus on the differential connotation of the two terms (see Tab. 6.1). [Pg.127]

The precautionary approach (PA) is an important element of environmental law that is used to address a potential risk whether or not that risk can be demonstrated or its consequences identified. The static use of a sole, generally accepted definition of the PA is extremely difficult, since this cannot meet the multitude of needs in important legislative tools introduced in many conventions designed to protect biodiversity. The way out will be a more discursive model, a model that allows for adaptation to specific conditions and which enforces solution-oriented procedures. [Pg.291]

Discussions about the PA usually focus on definitions. Such definitions are plentiful, they depend on the scientific and social background of their authors, and they all contain elements of truth and error. One of the basic problems with the PA is that there is no such thing as an overall definition. The application of the PA is always heavily context-dependent. It is no use solving problems associated with applying the PA by means of a generally accepted definition, since it is difficult to define a principle sharply where uncertainty is the main element. The definition of terms and concepts like uncertainty always depend on the scientific, social, cultural and economic background of individuals employing them. [Pg.292]

Microemulsions are a convenient medium for preparing microgels in high yields and rather uniform size distribution. The name for these special emulsions was introduced by Schulman et al. [48] for transparent systems containing oil, water and surfactants, although no precise and commonly accepted definitions exist. In general a microemulsion may be considered as a thermodynamically stable colloidal solution in which the disperse phase has diameters between about 5 to lOOnm. [Pg.143]

Despite nearly two centuries of intense scrutiny, aromaticity remains a unique research stimulus in chemistry. The concept of aromaticity is elusive it is not directly observable. Numerous indirect measures have been devised, based on the manifestations and ramifications of aromaticity. One of the most recent and widely accepted definitions [2] described aromaticity as a manifestation of electron delocalization in... [Pg.419]

Quantification of the limits of detection (LOD), or minimum detectable levels (MDL statistically defined in Section 13.4), is an important part of any analysis. They are used to describe the smallest concentration of each element which can be determined, and will vary from element to element, from matrix to matrix, and from day to day. Any element in a sample which has a value below, or similar to, the limits of detection should be excluded from subsequent interpretation. A generally accepted definition of detection limit is the concentration equal to a signal of twice (95% confidence level) or three times (99% confidence) the standard deviation of the signal produced by the background noise at the position of the peak. In practice, detection limits in ICP-MS are usually based on ten runs of a matrix matched blank and a standard. In this case ... [Pg.204]

The two distinctive affinities in the surfactant molecule mentioned above serve as the basis for the commonly accepted definition of surfactant groups. According to the charge of their hydrophilic moiety, surfactants can be classified into four categories anionic, non-ionic, cationic and amphoteric. [Pg.32]

There are numerous ways in which an ionic liquid can be defined, and perhaps the most widely accepted definition is ... [Pg.75]

From the preceding discussion we might want to buy into the argument that terrorism is relative, a personal judgment. But is it really relative Is it a personal judgment What is terrorism Take your choice. Seemingly, there is an endless list of definitions and no universally accepted definition of terrorism. However, since terrorism is the main theme of this text, let s review a few of these definitions. [Pg.23]

There is no universally accepted definition of an artificial neural network. However, some definitions can be found in the literature, and examples are cited here. [Pg.3]

To learn the characteristic properties of the biochemical systems considered in this study and to assess their ability to perform as ANNs, a direct comparison between the two is made here. In so doing it should be noted that there is no universally accepted definition of an artificial neural network. Therefore, we refer here to the characteristics of ANNs summarized from some of the definitions available in the literature [17-22]. The next step is to examine if the characteristics mentioned above can also be found in the biochemical networks proposed in this study. These characteristics are compared one by one in Table 5.2. [Pg.129]


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