The purpose of the article is to analyze the influence of the properties of the range of colors (long-wave, medium-wave, and short-wave) on a person`s feelings, his or her psycho-emotional perception, and consider these features in the design-projecting of jewelry. Also, to create further prospects for expanding the consumption of such jewelry in both domestic and foreign markets. Methodology. To conduct research, a set of general scientific approaches was used, in particular: visual-analytical, system-informational, modern methods of analysis of mechanical systems, and the method of classifications. Results. The features of the influence of color properties on the psycho-emotional perception of every person have been revealed. The designs of jewelry have been developed using some specific color ranges that will create an attractive, festive atmosphere, to identify a wider and more effective application of these features. Scientific novelty. Specific features of the influence of color and a certain color range on the formation of the appropriate psycho-emotional mood of a person have been identified, which must be considered in the design-projecting of jewelry. The variants of effective use of special properties of the color range of an enamel covering have been proposed to increase the consumers` interest in new developments of jewelry in both domestic and foreign markets. Practical significance. Practical recommendations and options for using the appropriate color range of enamel covering that can create certain psycho-emotional feelings (good mood, creative inspiration, passivity, indifference, aggression, etc.) have been proposed to extend the application of enamel coverings in the creation and development of various types of jewelry.

The questions of design maintenance of a given fatigue longevity of rods of complex form during the intensification of load modes without changing of geometric, inertial and rigidity parameters of roads are considered. The study is conducted on the example of needles of circular machines with a small diameter of cylinder (automatic half-hose machines). An approach, based on the system of calculation of loads, loadings and resources under the criterion of fatigue strength, is proposed. The key link for the transition from the results of dynamic analysis to the determination of reliability indices is the dependence of limited longevity of needles on the cycles of load to fatigue failure with the use of statistical data on operating time to fatigue failure of the needles in production conditions. Since the random values of loads of the needles do not obey the normal law of distribution, the general description of density of distribution of amplitude of loads is presented. The influence of increase in speed parameters and constructive measures, aimed to reduce the corresponding loads at a current size of critical section of the needles, on the fatigue longevity is analyzed.

The purpose of the work is to develop the algorithm for calculation of the probability of failure-free operation of flexible plates of complex shapes for the cams, using the criterion of fatigue strength, to make decisions on minimization of their sizes with the subsequent evaluation of the implemented measures. The studies are performed on the example of a plate for the cam, the configuration of which provides both beam and double console deformations at the same time. The comprehensive approach is presented, which includes dynamic analysis of the needle impact on the cam surface, computer simulation of geometric parameters of the plate by the finite element method (FEM) according to the condition of strength, and classical principles of mathematical statistics and Theory of Probability. The finite-element model with a volumetric 8-node element is used, which allows, with ease of calculations, to obtain the results with a high accuracy when determining the stress-deformed state of the study object. The computer simulation is performed using Code_Aster software with free access. Also, in the calculation of reliability, the random nature of the multifactorial influence on the value of the plate fatigue limit and the loading variations of the cam are considered. When determining the equivalent forces, taking into account the cyclical operation of the machine, the forces that affect the cams during the production of one product are taken as a loading. The numbers of cycles corresponding to these loadings are calculated by the formulas, which are made as a result of the analysis of trajectories of needles motion concerning the cams when knitting different sections of the product. When calculating equivalent stresses, only stresses that influence the accumulation of fatigue failures are used, that is, the values greater than the half of the detail fatigue limit. The proposed computational approach can be used to generate the cams with flexible work plates of different configurations, including under the equal stress condition.

The article states that the use of composite materials instead of traditional materials allows you to significantly reduce the weight of the product, while not changing the strength characteristics of this material. It was determined that polymer composite materials based on metal powders, high-strength organic (aramid) and carbon fiber fillers with a polymer matrix are promising for use as structural materials. Fillers are used to improve the operational properties of the composite material (strength, stiffness, heat resistance), give them various specific properties and reduce the cost. The classification of polymer composite materials by matrix and filler is presented. It is noted that the greatest variety of properties can be obtained using solid fillers of different nature (metals, ceramics, polymers) and structures. It has been established that both the type of filler and the shape and size of the particles are important when forming certain properties of polymer composite materials. It was determined that composite materials are used in additive technologies, in particular in 3D printing. Examples of the production of composite filaments by various companies, including various types of fillers, are given. The developed technology of printing with a mixture of polymer connector and filler using a 3D printer, which includes certain stages, is presented. Polymer materials and solid fillers of various nature were selected as the matrix for experimental research and their properties were described. The classification of equipment for forced mixing of materials is described. The developed extruder that prints with granules or composite mixtures of polymer materials and the 3D printer on which it is installed are presented. Composite mixtures for conducting experimental studies are given. The parameters of the printed samples to be examined are specified.

The purpose of the work was analytical research and computer modeling of the influence of shape and size of console beams of elastic plates in non-base configurations for the cam of the automatic half-hose machine under the conditions of flexibility, strength, and minimization of sizes. The scientific novelty of the work lies in the further development of the theory and methodology of designing the elements of knitting systems of the automatic half-hose machines based on regimes of loading, limitations in strength and dimensions, as well as requirements of the technological process. In order to increase the flexibility of the elastic plate, the symmetrical introduction of two console beams of trapezoidal shape was proposed. The influence exerted by the coefficient of the shape of console beams and their lengths on the magnitudes of deflections and stresses was analyzed, which allows making grounded and flexible decisions regarding the dimensions of the root and the end sections of the beams at the preliminary stage of design. The mathematical support was presented mainly in an explicit form, which simplified the analysis of the influence of controlled dimensions of the elastic plates on their flexibility and strength, as well as contributes to the comprehensive approach to the development of cams of different constructions with elastic plates and allows improving the quality and efficiency of design solutions of cams. The beam bending theory and the finite element method based on Code_Aster shared software were used. The model of the plate was represented by an ordered grid of finite nodal elements of the same size, without the use of elongated and flat elements. According to the results of simulation experiments, the distributions of deformations and stresses on the surface of the elastic plate of the cam were obtained, depending on its shape and size, which confirmed the validity of calculated recommendations.