Application of probability-based multi-objective optimization in material engineering

Introduction/purpose: Althought many methods have been proposed to deal with the problem of material selection, there are inherent defects of additive algorithms and subjective factors in such algorithms. Recently, a probability-based multi-objective optimization was developed to solve the inherent shortcomings of the previous methods, which introduces a novel concept of preferable probability to reflect the preference degree of the candidate in the optimization. In this paper, the new method is utilized to conduct an optimal scheme of the switching material of the RF-MEMS shunt capacitive switch, the sintering parameters of natural hydroxyapatite and the optimal design of the connecting claw jig. Methods: All performance utility indicators of candidate materials are divided into two groups, i.e., beneficial or unbeneficial types for the selection process; each performance utility indicator contributes quantitatively to a partial preferable probability and the product of all partial preferable probabilities makes the total preferable probability of a candidate, which transfers a multi-objective optimization problem into a single-objective optimization one and represents a uniquely decisive index in the competitive selection process. Results: Cu is the appropriate material in the material selection for RF - MEMS shunt capacitive switches; the optimal sintering parameters of natural hydroxyapatite are at 1100°C and 0 compaction pressure; and the optimal scheme is scheme No 1 for the optimal design of a connecting claw jig. Conclusion: The probability-based multi-objective optimization can be easily used to deal with an optimal problem objectively in material engineering.

Rehabilitation aspects of nutritional correction after extensive combined sequity resection

The purpose is the tactics of nutritional rehabilitation after extensive intestinal resection. The metabolic characteristics of the short intestine syndrome and the consequences of combined fine-binding resections, as well as the adaptive and regenerative capabilities of the bowel, are presented. The optimal scheme of nutritional correction for the consequences of combined bowel resections is presented.Conclusion. To stimulate adaptive-regenerative processes in the intestine, it is advisable to use teduglutide (analogue of GLP-2); if ineffective, surgical rehabilitation can be recommended.

Frequency manipulation of a light-activated shape-memory polymer-laminated cylindrical shell

A light-activated shape-memory polymer is a novel smart material that exhibits a dynamic Young's modulus when exposed to light. The non-contact actuation feature facilitates the lamination of a light-activated shape-memory polymer on host structures for realising frequency control. In this study, we investigated the natural frequency of a simply supported cylindrical shell coupled with light-activated shape-memory polymer patches located arbitrarily on the shell. Initially, we compared the natural frequency of a completely laminated cylindrical shell using two different approaches. Further, we analysed the effect of changes in the length and location of the light-activated shape-memory polymer patch pair on the natural frequency of the cylindrical shell. Based on the experimental results, we propose an optimal scheme, wherein several light-activated shape-memory polymer patch pairs are distributed on the surface of the shell, and the frequency control capability of the proposed scheme is evaluated comprehensively. The results verify that the optimal scheme has an adequate control effect on the natural frequency of the cylindrical shell.

Red beet in the Republic of Dagestan

Представлены материалы экспериментальных исследований по разработке элементов технологии возделывания столовой свеклы на луговых среднесуглинистых почвах сухостепной равнинной зоны Дагестана. Цель исследований – повышение урожайности свеклы столовой на основе выбора оптимальной схемы и густоты посева свеклы сорта Бордо 237, а также применения регулятора роста Биостим Универсал с использованием системы капельного орошения. Фактор А – схемы посева с двумя вариантами: А1 – широкорядный посев с междурядьем 45 см (контроль) и А2 – двустрочный ленточный посев по схеме 20+50. Фактор В – густота посевов с тремя вариантами: В1 – расстояние в ряду через 6 см, В2 – через 8 см и В3 – через 10 см соответственно, что в зависимости от схемы посева обеспечивало густоту посева столовой свеклы от 222 до 473 тыс. шт/га. Фактор С – обработка растений с двумя вариантами: С1 – опрыскивание водой (контроль) и С2 – некорневая подкормка биостимулятором-антистрессантом Биостим Универсал (в фазе 4–6 листа) и при 50%-ном смыкании рядков (в фазе 8–10 листа). Доза применения препарата – 2,0 л/га с расходом рабочего раствора 200–400 л/га. Система капельного орошения состояла из поливных трубопроводов с расстоянием между ними 0,7 м, между капельницами – 0,3 м с расходом воды 2 л/ч. Средний срок посева – первая декада апреля. Поддержание необходимого режима орошения свеклы столовой обеспечивали вегетационными поливами с нормой 125 м3/га при оросительной норме 2875 м3/га. Выявлено, что наиболее оптимальная схема посева столовой свеклы: двустрочный ленточный посев – 20+50 см с расстоянием в ряду через 8 см, которая при двукратной некорневой подкормке препаратом Биостим Универсал в дозе 2,0 л/га с расходом рабочего раствора 200–400 л/га обеспечивает урожайность 59,8 т/га корнеплодов при их высоком качестве. The materials of experimental studies on the development of elements of the technology of cultivation of table beets on meadow medium loamy soils of the dry-steppe plain zone of Dagestan are presented. The purpose of the research is to increase the yield of table beet based on the selection of the optimal scheme and the density of sowing of Bordo 237 beet, as well as the use of a Biostimulator growth regulator using a drip irrigation system. Factor A is a seeding scheme with two options: A1 is a wide-row seeding with a row spacing of 45 cm (control) and A2 is a two-line ribbon seeding according to the scheme 20+50. Factor B is the density of crops with three options: B1 – the distance in a row after 6 cm, B2 – after 8 cm and B3 – after 10 cm, respectively, which, depending on the sowing scheme, provided the density of table beet sowing from 222 to 473 thousand pcs/ha. Factor C – treatment of plants with two options: C1 – spraying with water, control and C2 – foliar feeding with biostimulator-antistressant Biostim Universal (in the phase of 4–6 leaves) and with 50% closure of rows (in the phase of 8–10 leaves). The dose of the biostimulator is 2.0 l/ha with a working solution consumption of 200–400 l/ha. The drip irrigation system consisted of irrigation pipelines with a distance of 0.7 m between them, 0.3 m between droppers with a water flow rate of 2 l/h. The average sowing period is 1 decade of April. Maintenance of the necessary irrigation regime of the canteen beet was provided by vegetation irrigation with a rate of 125 m3/ha with an irrigation rate of 2875 m3/ha. It was revealed that the most optimal scheme for sowing table beets: two-line ribbon sowing – 20+50 cm with a distance in a row through 8 cm, which, with two-fold foliar top dressing with a Biostim Universal at a dose of 2.0 l/ha with a working solution consumption of 200–400 l/ha, provides a yield of 59.8 t/ha of root crops with their high quality.

A Joint Grid-Source Planning Method Considering Adaptability of Power System

With the large-scale renewable energy access to the power grid, the construction and operation state of the power system have been greatly changed. Therefore, the adaptability of power system to deal with the fluctuation and uncertainty of renewable energy is of great significance to ensure the safe and stable operation of the system and promote the consumption of renewable energy. Based on the structural characteristics and operation status of the power system with high proportion of renewable energy, the adaptability index of the system construction and generators capacity is proposed, which takes into account the security, validity, stability and supply-demand balance of the power system, and comprehensively evaluates the acceptance capacity of the system to the renewable energy. On this basis, a multi-objective power system planning model based on grid-source coordination considering both economy and adaptability is established. The optimal scheme is obtained through the comprehensive decision of the optimal scheme set by the nonlinear improved principal component analysis. Finally, the effectiveness of the adaptability index and the planning model is verified by an example simulation with the improved Gaver-18 system.

Analysis of chromatic aberrations influence on operation of the tunable AOTF-based source

Developing a source with the possibility of tuning in wavelengths based on an acousto-optical tunable filter (AOTF), an essential factor is the ability to provide accurate color coordinates of the simulated color (in the case of developing a color standard for colorimetry) or the required wavelength (in the case of an application for spectral studies). As shown earlier, the choice of the principal layout – confocal or parallel beam path - primarily determines the dimensions and efficiency of using the luminous flux. However, these schemes also need to be analyzed for color or wavelength fidelity, considering other components used in the scheme. The analysis performed allows to identify the optimal scheme to ensure the required color reproduction accuracy and establish the requirements for correcting chromatic aberrations of the components.

DETERMINATION OF THE OPTIMAL SCHEME FOR THE DEVELOPMENT OF A CUTTING AREA ACCORDING TO THE DEGREE OF UNDERGROWTH PRESERVATION

The article is devoted to the substantiation of the optimal scheme for the development of felling areas according to the degree of preservation of undergrowth. For this, three options were explored. The first method involves the laying of apiary trails, followed by the development of half-incisions with ribbons of a certain width, starting from the nearest to the apiary trail. In the second method of apiary development, the laying of apiary trails is not assumed and the felling of trees occurs inside the plantation on a belt of a certain width located perpendicular to the main trail. The third method of apiary development, proposed for comparison, involves the use of technological sighting devices at an angle to the main and apiary technological corridor. To compare the indicated methods of performing processing operations in apiaries, analytical expressions were obtained to determine technological areas and a calculation of all their components was performed.