Читать книгу The ABC of Qualimetry. The Toolkit for Measuring Immeasurable - Garry G. Azgaldov, Alexander V. Kostin - Страница 5

1.1.1. The Essence of Quality and Quality Control

The Concept of Quality and What Makes It Different from Other Similar Concepts

As already noted in the Introduction, Quality Control is one of the main applications for qualimetry.

Unfortunately, modern economic theory and economic practice alike, has unambiguous and common interpretations of the terms quality and control, leading to frequent misunderstandings with resulting in completely different approaches to many important issues. For example, “What really happens to an object (e.g., life quality), which, as often claimed, is being controlled?” Is the process indeed a control one? Is it indeed quality and not something else that is subject to control?”

These are not idle questions. Unless we figure them out we cannot count on success in addressing the issue of quality. Therefore, let us clarify our definitions of the key terms, quality and control. At the outset we introduce some terms based on which it will be possible to define the desired term, quality control.

Object, a thing or a process; as applied to the theme of these introduction:

– An animate thing (e.g., a city dweller) or an inanimate one (e.g., a motor car);

– A product of labour (e.g., a dwelling house) or a product of nature (e.g., a natural landscape around an urban settlement);

– A physical object (e.g., an industrial enterprises) or an ideal one (e.g., an artwork made out in a book title);

– A natural object (e.g., a landscape) or a man-made one (e.g., a set of landscape design structures);

– A product (e.g., a piece of clothing) or a service (e.g., a medical service);

– Items (e.g., motorways) or processes (e.g., life activities, which collectively form the quality of life).

In what follows the term object will apply to an object (which can be called “singular”) such that its quantity, in common measurement units, equals one. Then, a city can be an object but not three cities taken together; likewise one airplane, one specialist, etc.

Property. A feature, characteristic or peculiarity of an object, that becomes apparent during its consumption/operation/use/application (henceforth, all these terms are used interchangeably) according to the purpose of its use (e.g., the mean lifetime of a community).

The mention of the condition “according to its purpose” is caused by the following considerations: Imagine an emergency situation in which indoor sports facilities have to be used as temporary shelter for the inhabitants of a city whose homes were destroyed in a disaster (such as caused by Hurricane Katrina in New Orleans in 2005). The floor area of the interior, which can accommodate refugees, would seem to be a characteristic of a sports structure. The thing is that this kind of utilisation of athletic facilities is abnormal, out of keeping with their purpose. Therefore, a feature of a sport hall such as “the number of refugees it can accommodate” cannot be regarded as its “property” in a qualimetric sense.

We draw the reader’s attention to one more circumstance, which, although mentioned in the definition of the term property, is sometimes neglected in practice. Properties are not just any features/characteristics/peculiarities of an object, but only those that occur during its production or consumption/application/use/operation.

For illustration we give the following example (which for greater clarity relates to product quality). Any product made of a ferromagnetic material is known to possess the quality of magnetostriction, that is, the ability to change its shape and size in response to changes in the magnetic field.

Let us consider two different kinds of products made of a ferromagnetic material: a mechanical chronometer watch and the track shoes of a caterpillar tractor. Obviously, magnetostriction is incident to both.

In a chronometer magnetostriction shows in the way its accuracy is affected by exposure to a strong magnetic field. As for tracks, the phenomenon of magnetostriction in a physical sense does take place during their operation, but its impact (e.g., the magnitude of the absolute and relative changes in the linear and volumetric dimensions of the tracks) does not affect the performance of the tracks as part of a caterpillar belt. We can assume, therefore, that magnetostriction is not manifested in the consumption of these products (that is not in a physical but an economic sense.)

It follows that for an object like a chronometer watch, the presence of magnetostriction is to be considered one of its properties, whereas for a caterpillar track it is not a property in the sense outlined above in the definition of property.

Quality is a property representing a set of those and only those properties that characterise the consumption results of an object, both desirable and undesirable, excluding the cost of their creation and consumption. That is to say, this set includes only properties associated with the results achieved in consuming an object, and does not include ones associated with the cost of providing these results.

Notice that:

(1) The properties that constitute quality do not include those that manifest themselves in the course of production/creation/development/manufacture of objects (hereinafter, unless otherwise indicated we shall generally use instead of four terms – production, creation, development, manufacture – a single umbrella term, production);and

(2) The entire life cycle of an object will be conventionally considered to consist of only two broad stages, those of production and consumption, with the consumption stage including what is known as distribution (which is only applicable to some objects, e.g., products of labour but not the quality of life).

Thus, when we analyse the quality of an object we can – even must – ignore its manufacturing technique and its production and consumption costs and focus instead on the results, both positive and negative, achieved at its consumption stage.

Cost Effectiveness. The totality of properties characterising the capital input into the production and consumption of an object. (In some cases cumulative costs can be represented by so-called reduced costs or full costs.).

From the definitions and interpretations of the terms quality and cost-effectiveness it follows that the entire set of properties of an object can be divided into two disjoint subsets: the properties that form the quality of the object and those that form its cost effectiveness.

As consumers are not normally only care for either the quality of an object ignoring its cost effectiveness or, alternatively, its cost effectiveness without regard to its quality, the science of qualimetry, naturally, felt the need for a characteristic that would take into account the entire set of properties associated both with the consumption of an object (its quality) and the costs incurred (its cost effectiveness).

This characteristic is termed integral quality in qualimetry.

Integral quality. The property of an object describing the sum of its quality and cost effectiveness. Thus, integral quality is the most general characteristic of an object, which factors in all of its properties.

It should be noted that the engineering and economic literature uses concepts and terms similar in meaning to the ones introduced above, quality and integral quality. We will consider these concepts starting with those who are close to the concept of quality.

The term engineering level is usually applied to the quality of products (but not, e.g., to the quality of life). It is almost identical in scope to the term quality. However, it has several shortcomings compared to the latter:

(a) In a purely linguistic sense, with some objects this term is perceived as much less suitable than quality. Imagine pronouncing phrases like “the engineering level of ladies” perfume”, “the engineering level of milk,” “the engineering level of a specialist,” “the engineering level of a managerial decision,” or “the engineering level of life.” Substituting quality for engineering level immediately improves the sound of these identical terms: “the quality of ladies” perfume,” “the quality of milk,” “the quality of a specialist,”“the quality of a managerial decision,” “the quality of life.”

(b) The term quality has a long history dating back to Aristotle’s days, while the term engineering level came into being (mainly in the Russian literature) in the last 30 – 35 years. This brings up the natural question: why use a new term if we have a long-established synonymous term?

(c) It is common knowledge that the quality of a finished product is defined by three factors: the quality of its design, the quality of its raw materials and semi-finished products, and the quality of its manufacture (that is, the extent to which its design parameters are met in manufacture).Sometimes the term engineering level refers to what is termed design quality in qualimetry.

Then the question arises: why introduce a new term, engineering level, if we can do with the good old term, quality (or more precisely, design quality)?

For these reasons, in the science of qualimetry (and in this ABC) the term engineering level is not used.

The term technical excellence is an absolute synonym of engineering level. Therefore, all that was said above regarding engineering level applies to technical excellence.

The term utility describes a property that characterises the aggregate of quantity and quality of an object (see, e.g., [1]).

For example, the utility of two houses is greater than that of one of exactly the same quality. However, utility and quality means the same thing when applied to one unit of quantity of an object. That is to say, we can assume that quality is the utility of one unit of quantity of an object. Since the quantitative estimation toolbox is better designed for quality than for utility in what follows we will use mainly the term quality, that is to say, consider mainly objects whose number is equal to one unit.

The term value is synonymous with utility but its use is normally restricted to the philosophical literature. All that we have said above about utility holds for value.

Concept of use value. If as shown above, quality is the utility of an object unit (that is, a property inherent in the object),use value is the object possessing this property, i.e. utility. As applied to an object whose quantity equals unity, use value is the object possessing this property whose quantity equals unity (see [1]). As the subject matter of this ABC is the quality of an object (e.g., the quality of life) and not its quantity, hereafter the concept of use value will not be generally used and our exposition will be in relation to the concept of quality.

The term efficiency has many different interpretations. With regard to the most commonly used one it is very close to integral quality. However, because of its ambiguity we will use it instead the term integral quality. On the other hand, since most of the statements relating to the concept of quality remain in force and applicable to the concept of integral quality, the latter will be used hereafter only in specified cases.

We introduce some more concepts related to the concept of quality.

Property / quality / integral quality index. Is a quantitative characteristic of a property / quality / integral quality.

Index value. Is a specific numeric value that an index can take. For example, the values for the property index “room temperature” can be 20° С or 22° С. Here the numerals 20 or 22 are the values of the property index. Similarly the term index value can be illustrated (this time in dimensionless units) with reference to quality. Let the quality index be expressed by the symbol К^к. Then in the expression К^к = 0.68 the numeral 0.68 is the value of К^к.

Where quality is analysed in general terms (i.e., not in a numeric but in an alphabetic form) the value of the index is expressed not by a numeral but by a lowercase letter (as opposed to the index itself, which is always denoted by a capital letter). For example, the expression K^К= k₁^K reads as follows: the quality index K^K has the value k₁^K. This applies to a quality index but also to a property index, an integral property index, etc.; to any index at all.

After we have clarified the meanings of the basic concepts related to the term quality we can analyse concepts related to the term control, which is in practice often linked with quality (e.g., in phrases like “product quality control”).