Инновационные процессы в исследовательской и образовательной деятел

A.A. Kasatkin

Perm National Research Polytechnic University

OPTIMIZATION OF THE TWO-LEAF ELASTIC ELEMENT

The aim of the research was the optimization of the two-leaf spring type elastic element. The elastic element was modelled as the two cantilever beams (leaves). The leaves were different in length, but had the same width. The lower leaf had constant thickness and the upper leaf had variable thickness. The bending of each leaf is described by Bernoulli-Euler model. There was the contact between the leaves. Therefore, the bending problem belongs to the class of the beam contact problems. The optimal parameters of the elastic element were found.

Key words: elastic element, two-leaf spring, contact problem, equal-stress elastic element, optimization.

The leaf springs are widely used in cars, trucks and other vehicles [1]. They are also used in biomechanics – in foot prostheses of different design [2]. Therefore, to design and make durable and reliable leaf springs is an urgent task. The spring whose overall size and rigidity are given is considered optimal if it undergoes minimum stresses at a given load.

The elastic element is modelled as the cantilever two-leaf spring, i.e. each leaf has one end which is clamped and the other one which is free (Figure). The leaves are made of the same material; they have different length, but the same width (in the direction perpendicular to the plane as shown in Figure). The bottom leaf has constant thickness (h1(x) = const) and the top leaf has variable thickness, in other words, the thickness that varies according to the law h2(x) = h20(1+αx). The system is loaded by the force F concentrated at the tip of the lower leaf. In the absence of loading the leaves are straight and fit each other closely. There is no friction between the leaves. The bending of each leaf is described by Bernoulli-Euler model. There is the unbonded contact between the leaves, i.e. the upper leaf may be disconnected from the lower one (leaves are not “glued”), but it is impossible for the top leaf to penetrate under the lower one. Therefore, the bending problem which, in the process of optimization, should repeatedly be addressed belongs to the class of beam contact problems.

y

	h20	L2	L1	x
0		h1

F

Fig. The model of the elastic element

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The solution to problem requires finding the deflection of the spring and the stresses developing in it. This problem is reduced to finding the interaction forces (contact load) of beams. Commonly applied analytical solutions [4] do not cover the case of a linear thickness variation of the top leaf, which was considered in this paper. Therefore, the numerical solution method was applied [5]. Continuous contact load was discretized as a set of concentrated forces. To find the contact area the following iterative scheme was used:

1.First, the contact area (i.e. set of points of application of contact forces) is chosen arbitrarily.

2.Then, when contact area is known, we find contact forces within it and the distances between the leaves outside the area (distances are zero in the contact area itself).

3.If there are negative contact forces (i.e. the bottom leaf "pulls" the top leaf down), which contradicts the condition of unilateral contact, the points of application of these forces are eliminated from the contact area and we go to step 2.

4.If there are negative distances, which contradicts the condition of nonpenetrating the top leaf under the bottom leaf, we add the points at which distances are negative to the contact area and go to step 2. If all distances are non-negative, the contact problem is solved, that is, the contact forces and the contact area are found.

The contact forces and the contact area being known, it is possible to find the deflection of the spring and maximum stress in it max . The stress in each

leaf (the only significant component of the stress tensor xx ) depends on the coordinate x, so

		1			2
max max max			(x)	, max		(x)
	0 x L1			0 x L2					.

Having the algorithm to solve the contact problem makes possible the elastic element optimization. In the course of optimization the thickness of bottom leaf h1, the length of the top leaf L2 and parameters h20 and α that determine the thickness of the top leaf varies. The length of the bottom leaf L1 and the load F must be predetermined as well as the deflection of the spring ∆0. It is necessary to minimize the maximum stress in the spring. Thus, we get the problem of constrained minimization of the function of four variables: σmax(h1,

L2, h20, α) = min, provided ∆(h1, L2, h20, α) = ∆0. It can be shown that, due to the special structure of the functions σmax and ∆, this problem reduces to the pro-

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blem of unconstrained minimization of the function of three dimensionless variables:

f(L2 L1 , h20 h1 , L1)

max (1, L2 L1 ,h20 h1 , L1) (1, L2 L1 ,h20 h1 , L1)23 min. .

This problem was solved (numerically) by Nelder-Mead method.

As a result, we obtained the following parameters of the optimal elastic element:

L2 L1 0,653; h20 h1 1,536; L1 1,027

(the value h1 found from the condition ∆ = ∆0).

It can be shown that the optimal elastic element is equal-stressed in the following sense. There is a segment x1≤ x ≤ x2, where σ1(x)≡σ0 = const, and the maximum values |σ1(x)| and |σ2(x)| are equal σ0. This result is consistent with the well-known fact concerning equal-stressed optimal springs [3]. At the same time, we can show that in this case, the conditions of equal-stress do not uniquely determine the optimal parameters of the elastic member. The interconnection of optimality and equal-stress should be the subject of further study.

References

1.Пархиловский И.Г. Автомобильные листовые рессоры – М.: Машиностроение, 1978. – 232 с.

2.Mathematical modelling of the foot prosthesis elastic element under bending / M.A. Osipenko [et al.] // Russian Journal of Biomechanics. – 2001. – Vol. 5, No. 2 – P. 18–29.

3.Осипенко М.А., Няшин Ю.И. Об оптимизации упругого элемента протеза стопы // Российский журнал биомеханики. – 2011. – Т. 15, № 2. –

С. 16–23.

4.Осипенко М.А. Контактная задача об изгибе двухлистовой рессоры с листами переменной толщины // Вестник Томск. гос. ун-та. Математика и механика. – 2014. – № 1 (27). – С. 90–94.

5.Li H., Dempsey J.P. Unbonded contact of finite timoshenko beam on elastic layer // Journal of Engineering Mechanics. – 1988. – Vol. 114, No. 7. – P. 1265–1284.

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A.I. Krivorutchko

Perm National Research Polytechnic University

SOME DEONTOLOGY PRINCIPLES FOR LEGAL

TEXTS TRANSLATION PRACTICE

The article deals with some deontology problems of legal texts translation which are classified conveniently to imperative and optional ones. A particular attention is paid to the translator’s subjectivity which is revealed in his/her practice.

Key words: legal texts translation, imperative/optional translation deontology principles, translator’s subjectivity, translator’s competence, translator’s task.

Deontology problems associated with translation practice have become of importance quite recently due to which there is a difference in their interpretations. The role of a translator has changed from an impersonal communication participant and a “mechanic” text translator in the recent past to the present day elite linguistic identity. The essence of the concept and pre-supposed by the translator’s subject status exclusivity make us interpret to the followings terms: “translator’s ethics”, “translation deontology principles”, “translator’s competence”, “translator’s task” and others.

The study was based on legal written texts in English and their translation into Russian. The translator, being a subject of intercultural and interpersonal communication, is limited by strict legal culture limits and he must translate authentic texts for accepting culture in the most objective, correct and professional way. At the same time as the translator is individuality, he/she perceives and transmits information with an inevitable subjectivity in his/her practice. The revelation of the translator’s subjectivity could become a distinct subject of the study. The subjective component of the translation practice, underlined by the scientists, leads to the problem of the translation ethic which presents a “silent” code of the correct translation laws that open new perspectives within an anthropocentric approach to translation.

The analysis of deontology translation principles is based on the imperative/optional dichotomy. The terms “imperative” and “optional” are drawn on the social research performed by Rzhanova S.A. (2013) [1]. Within this study the term “an imperative in translation practice” is understood by us as a complex of the conduct principles prescribed by the professional ethics as opposed to the term “an optional in translation practice” which we understand as a complex of subjective, individual principles “if the communication aims demand it” [1, p. 116]. This opposition though is of conventional character.

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To imperative translation principles, described in the study of E.V. Alikina [2], we refer the following:

–confidentiality (the respect of professional secret information related to the Sender and the Receiver of the message);

–respectability (as a principle conferred to the translator’s moral portrait and as a corresponding way of relationship building with communication parties);

–responsibility (to the Sender and the Receiver for the level and quality of the translated text as a product of the translation practice). In our opinion, this principle is of particular importance in the legal texts translating process as this rule violation by the translator can cause serious property loss, an emotional distress, it also can lead to misrepresentation of this profession social significance and of the translators’ reputation on the whole;

–collective solidarity (the principles prescribing relationship solidarity within the collegiate community and the reputational image respect both of an independent translator and of translators’ community on the whole);

–neutral position (the principles of neutral and single translator’s position to all communication parties);

–common cultural principle of politeness.

Among optional translation principles the following can be described:

–“to be friendly and sympathetic”, according to the rule, mediated by “the real-life communication logic in various situations, speech genres and interaction purposes” [1, p. 116];

–“to be crucial to oneself and to one’s own abilities» and to manifest abilities to correct one’s work, «to learn from personal mistakes and those of others” [3, p. 131];

–to respect conduct rules established by the social medium [1, p. 116]. The deontology principles of legal texts translation presume referring to

the term “translator’s competence” understood by us within the article as “competence in languages, cultures, various areas of activities, intercultural communication, the translation quality respect, analysis and improving one’s own knowledge and skills” [4].

The term “translator’s competence” receives an interesting interpretation in French scientists’ works. The aspect important to us is the correlation between the terms “translator’s competence” and “translator’s task”. As the example we give the following definition made by Georgiana Lungu-Badea, of a

Romanian university professor: “La tâche du traducteur consiste à traduire, analyser, critique, choisir les plus adéquates solutiones et à évaluer pour tirer des conclusions sur la qualité, les possibilités d’amélioration du processus de traduction, etc.” [5, p. 79]. (“A translator’s task involves translation, analysis,

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critics, choice among the most adequate solutions and evaluation in order to make judgments about quality, possibilities of improving translation process and so on”, translated by us. – A.K.).

The author also underlines the deontological aspect of the translator’s task: “La tâche se rapporte nécessairement à l’éthique <…> ou aux éthiques de la traduction, concernant tout ceux qui sont impliqués dans le traduction, de l’auteur <…> et du traducteur <…> aux bénéficiaires <…>, démontrant par cela que l’identité et l’altérité, la compétence et la tâche se déterminent mutuellement” [5, p.79]. – (“The task is necessarily related with a science of ethics <…> or even sciences concerning translation involving all processes engaged in translation, from the author <…> and the translator <…> to the beneficiaries <…>, suggesting that subjectivity and variability, competence and the task of translating are mutually depended”, translated by us, A.K.).

In conclusion, it is worth mentioning that the translation ethics and translation competences are recognized by Russian scientists and the scholars abroad as being necessary for fulfilling various translation tasks.

It is supposed that the legal translation sphere which involves subjects and objects of law deserves closer study from the position of the deontology problems than any other area. In that case the translator would conduct his/her translation mission successfully.

References

1.Ржанова С.А. Социально-этические принципы речевого поведения

вмедиапространстве (на примере газетной речи) // Вестник Челябин. гос. ун-та. Сер. Филология. Искусствоведение. – 2013. – Вып. 81, № 22 (313). –

С. 114–118.

2.Аликина Е.В. Введение в теорию и практику устного последовательного перевода. – М.: Восточная книга, 2010. – 192 с.

3.Рябова М.Э. Интегративные процессы как основа повышения качества подготовки переводчиков // Интеграция образования. – 2014. –

№ 2. – С. 130–135.

4.Урубкова Л.М. Формирование коммуникативной компетенции переводчика [Электронный ресурс] – URL: http://www.rusnauka.com/SND/ Philologia/6_urubkova%20l.m.doc.htm (дата обращения: 02.04.2015).

5.Lungu-Badea G. Quelle(s) competence(s) traductionnelle(s) pour accomplir la tâche du traducteur [Электронный ресурс]. – URL: http://www.academia.edu/938489/RESSOURCES_OFFICIELLES_DE_TERMI

NOLOGIE_À_LUSAGE_DES_TERMINOLOGUES_DES_TRADUCTEURS_ ET_DES_INTERPRÈTES (дата обращения: 01.04.2015).

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Y.E. Kurbatov

Perm National Research Polytechnic University

THE TWO-STAGE MODEL OF THE CONCRETE

COMPOSITE FATIGUE WORK

The paper deals with the problem of forecasting the fatigue life of concrete structures, buildings and constructions. The authors propose the two-stage phenomenological model of damage accumulation for the numerical simulation of the fatigue life of concrete composite.

Key words: fatigue life, yield strength, damageability, dispersed phase, destruction kinetics.

Composite materials are increasingly used in the construction industry because they have a number of advantages compared to traditional structural materials. For this reason the problem that deserves close attention is the fatigue fracture mechanics of composites which is a complex process, influenced by different properties of composite components.

Among other structural materials concrete can be considered as a classic composite, whose mechanical properties are determined from the viewpoint of the composite mechanics apparatus. As the structure of the concrete material consists of aggregate and cement stone, – as well as micro cracks and voids between the matrix and the filler, – it can be assumed that under cyclic loading of concrete specimens the accumulation of fatigue damage will occur due to the destruction of the cement matrix. However, fatigue cracks as such are not yet formed at this stage. The fracture of the material is discrete and occurs at specific points of the matrix volume. This process may be determined as the dispersed phase (or stage) of fatigue damage accumulation.

As noted in [1], the emergence of cracks in the metal notched specimens, when the stress value is below the yield strength, is the result of very few loading cycles. The number of cycles range from 3 to 10 percent of the total fatigue life. However, concrete does not have a clearly defined limit of proportionality and yield strength. Therefore, the moment of transition from the dispersed phase to the stage of crack formation can be very different from the above numbers. Thus, in addition to standard task of describing the process of damage accumulation at each stage (by compiling kinetic equations), it is necessary to identify the moment of crack initiation, which, as a matter of fact, differentiate the first stage from the second one.

The description of the destruction kinetics at each stage is actually the determination of the amount of damage accumulated during an arbitrary period of time. In the research done by L. Sosnovskiy and S. Sherbakov [2] the main app-

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roaches to determining the accumulated damage value were described. This value is generally referred to as damageability of the material.

The damageability is most often defined as some abstract value, reciprocal of continuity, which ranges from 0 (completely solid material) to 1 (completely destroyed material). In real life the fatigue failure of the sample occurs long before the destruction of the material.

In the course of simulation it is convenient to use the damageability as the main indicator of the fatigue defects development, whether the latter are local points of structure (1st stage) or cracks (2nd stage). In our previous paper [3] we suggested the mathematical model of the one-stage discrete phase of the material behavior. The damageability was determined as a complex function depending on the loading criterion K and the number of cycles T:

П = f (К,Т).

(1)

Figure shows a supposed damage surface of the cement stone, corresponding to the relation given above.

In the framework of the two-stage model of concrete behavior the equation (1) may be applied but it can be used only before cracks start developing. Then the data obtained must be taken into account. After that it is necessary to continue the process of modeling the fatigue fracture using other kinetic equations, which include the apparatus of fracture mechanics.

Fig. The damage surface

Equation (1) will change: the damageability will depend on the stress intensity factor K and the number of applied cycles N. Now it must be calculated taking into account the crack length:

П = П0 + f (∆K, N).

(2)

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Values of ∆K and N can be obtained by equations found in [4]:

													a		1
					1										2
	K a 2										tg					,
									a
	1										1	m					m
N
										a			2 a01						,
		m															2
	c m			(1		m		)
			2
			2

(3)

(4)

where – stress amplitude,

2a0 – the initial length of the crack,

2a – the current length of the crack (after the application of N cycles), c, m – constants of the material.

It should be noted that these equations were obtained for the polyester composite reinforced with fiberglass. Obviously, they need to be specified and further testing to be used to calculate the concrete material. Furthermore, the fatigue behavior of the material can be considered in a number of ways, using different approaches, which is due to the variety of composites. Hence, the use of one universal equation for all cases is incorrect to say the least. However, for a preliminary assessment of the composites fatigue life in general, and the concrete fatigue life in particular, this technique is applicable.

References

1.Кулик Н.С. Математические модели накопления повреждений и трещиностойкости при действии статических и циклических нагрузок // Вiсник НАУ. – 2009. – № 3. – С. 3–23.

2.Сосновский Л. Концепции поврежденности материалов // Вiсник ТНТУ. – 2011. – Спецвип., част. 1. – С. 14–23.

3.Кашеварова Г.Г. Математическое моделирование усталостной прочности бетона при циклическом нагружении // International Journal for Computational Civil and Structural Engineering. – 2014. – Vol. 10, is. 4. – С. 96– 101.

4.Фудзии Т., Дзако М. Механика разрушения композиционных материалов: пер. с англ. – М.: Мир, 1982.

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K.V. Lipatnikov, E.S. Andreeva,

N.A. Tselischeva, E.A. Naugolnykh

Perm State Pharmaceutical Academy

SYNTHESIS OF BIOLOGICALLY ACTIVE 2-HYDRAZINOBENZO[D]THIAZOLE DERIVATIVES

The article deals with synthesis of new 2-hydrazinobenzo[d]thiazole derivatives based on 4-(het)aryl-2-hydroxy-4-oxobut-2-enoic acids. Conditions of reactions are described. The results of the study of biological activity of the obtained compounds by the program PASS Online are presented. 2- hydrazinobenzo[d]thiazole derivatives have been found to be potent biologically active substances.

Key words: benzo[d]thiazole, 4-(het)aryl-2-hydroxy-4-oxobut-2-enoic acids, PASS Online.

The search for new effective and safe organic molecules remains one of the priorities of Pharmacy. Various pharmacophores are introduced into the structure of substances with the aim of potentiating the biological action. 4-(het)aryl-2-hydroxy- 4-oxobut-2-enoic acids have been stated to be biologically active matrix allowing due to its reaction centers to introduce additional heterocyclic moieties, e.g. 1,3,4- thiadiazole and benzimidazole. It has been found that derivatives of 4-(het)aryl-2- hydroxy-4-oxobut-2-enoic acids containing the mentioned substituents exhibit pharmacological effects such as hypoglycemic, antimicrobial, anticoagulant, antiinflammatory [1, 2]. It is known that the fragment of benzo[d]thiazole included in the composition of the drugs, for example, pramipexole, riluzole, ethoxyzolamide. Consequently, the introduction of 2-hydrazinobenzo[d]thiazole fragment into initial matrix of 4-(het)aryl-2-hydroxy-4-oxobut-2-enoic acids in order to obtain new biologically active compounds is of interest.

Currently, the synthesis is carried out in two directions: preparation of

(Z)-2-[2-(benzo[d]thiazol-2-yl)hydrazinyl]-4-(het)aryl-4-oxobut-2-enoic acids (3a-g) and N-substituted hydrazides of 4-(het)aryl-2-hydroxy-4-oxobut-2-enoic acids (4a-g). The reaction scheme is presented in Figure.

The reaction proceeds at an equimolar ratio of reagents in a medium of ethanol or anhydrous chloroform at a temperature of 20–25 °С. Recrystallization is carried out using acetonitrile and dioxane. The structure of new compounds 3,4 is confirmed by IR and NMR1H spectroscopy. Purity of derivatives 3,4 is determined by the method TLC in ether:benzene:acetone (10:9:1).

The synthesized substances have been tested for biological activity using PASS Online, which can detect the presence or absence of different kinds of biological activity among the final products [3]. Data on the most likely effects of the compounds 3,4 are presented in the Table.

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