We propose a numerical-experimental method of determining the residual stresses in welded shells of revolution. We solve the inverse conditionally correct problem of recovering the complete picture of the residual stress state from part of the experimental values obtained by the method of photoelasticity. We apply the numerical spline-coUocation method.Residual stresses are those that exist in structural elements in the absence of external forces. Such stresses arise, in particular, as the result of various technological processes and have significant influence on the durability, strength, and reliability of the structures. In the complex of methods of determining and controlling the residual stresses an important place belongs to nondestructive (physical) methods [3]. For shell structures made of optically active materials, especially glass, the method of integral photoelasticity, in which tangential and normal illumination of the shells has been used [4], has proved to be effective. However, by this method one can exhibit only some of the components of the residual stress tensor. For example, for a shell of zero Gaussian curvature (cylinders, cones, and the like) this method does not make it possible to determine the circumferential components of the residual stresses, and for spherical shells with nonzero Gaussian curvature in the presence of metal inclusions it is impossible to find the circumferential components near the inclusion in this way because of the opaqueness of the metal.In this connection an experimental-theoretical method has been proposed and developed for determining the residual stresses in compound glass shells [3]. The method is based on solving inverse conditionally correct problems of recovering the residual strain field and the stress-strain state of a shell from part of the values obtained experimentally.Let us briefly describe the essence of the method. For a specific set of technological conditions of manufacturing a glass structure we describe the field of free residual strains whose incompatibility produces the residual stresses, taking account of the a priori picture of its qualitative behavior, by a certain function e ~ that contains a certain set of unknown parameters. Substituting the function e ~ in the equation of the theory of shells with intrinsic stresses, we find the solution of this system and write expressions for determining the residual stresses in which the unknown parameters occur. Equating the experimental values of some of the components of the residual stress tensor to the expressions corresponding to them computed theoretically, we find the unknown parameters. We find the width of the zone of localization of the residual strain field near the weld seam from the condition that a certain functional for the difference between the theoretical and experimental values of the stresses must have a minimum. Thus we recover the field of free residual strains, as the cause of the residual stresses, from part of the values of the stress tensor obtained experimentally.We now c...

We solve the inverse conditionally correct problem of recovering the complete picture of the residual stressed state for a compound shell welded from two parts, one cylindrical and the other conical. We apply the partial values of the stresses obtained experimentally by the method of photoelasticity. We also apply the numerical method of spline-collocations.The numerical-experimental method of determining the residual stresses in compound welded shells of revolution is One of the nondestructive methods oL~ontrol of the level of'such stresses. It is: based on: solving)inverse conditionally correct problems of recovering the complete picture of the stress-strain state of the shell from some of the values of the stresses obtained experimentally [4,6].We consider a shell structure made of optically active materials for which the method of integral photoelasticity [7] is an effective experimental method. For such materials, especially for glass, we describe the residual strain field by the spherical tensor o =80.e 0, Thus we have a finite-parameter representation of the field (1), and we regard the inverse of the problem of creating it as the problem of finding the parameters of the model just constructed in a finite-dimensional space, where each closed bounded set is compact [8]. For parametric models the following assertion holds [8]: if there

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The production of functional food products is one of the most important directions of development of the food industry. Particular attention is paid to the creation of new balanced in composition of products enriched with functional components, allowing them to increase their nutritional and biological value. Among vegetable crops, pumpkin is a highly valuable raw material in the food industry, which has equally both nutritional and biological value, and allowing for the correction of the human nutritional status. Based on this, we has been assessed the biochemical indicators of the varieties and hybrids of table pumpkin during to keeping as a perspectives raw material for the products of functional allocation in the Far East region. The research was carried out by the department of vegetable crops and potatoes of the Far Eastern Research Institute of Agriculture in the framework of the Far East program. Biochemical studies on pumpkin were carried out in the laboratory of agriculture of the Far Eastern Research Institute of Agriculture and in the laboratory of testing of the Center for Agrochemical Service “Khabarovsk” three times: 1 - before laying on to keeping; 2 - after 1.5 months of keeping; 3 - 1 month after the previous study. The results of studies showed that the varieties Nadezhda, Zimnyaya sladkay and Japanese hybrid Orange colon after 2.5 months of keeping, there was a decrease in some biochemical parameters. The varieties Vnuchka, Zhemchuzhina and a Japanese hybrid Sweet kob there is a tendency to increase almost all the quality indicators during the whole period of keeping. The content of dry matter, Vitamin C and potassium increases significantly. A favorable period for the processing of raw materials in the manufacture of the products of functional allocation is 1-2 months after harvesting for the Nadezhda variety and 1-4 months for the Vnuchka variety. Perspectives for the Far Eastern region in the manufacture of the products of functional allocation from foreign varieties are the Zimnyaya sladkay variety and the Japanese hybrid Orange colon.