Aspects of the formation of a tractor fleet of agricultural enterprises

Studies and production experience show that with an increase in the mass and power-weight factor of tractors, the return on investment in this technical progress field decreases. The paper justifies that at the current stage, the priority is to reduce the energy consumption of mechanized processes and comply with agro-technological requirements in the changing natural and production conditions. It reflects the areas of designing tractors and the effectiveness of their operation. The compaction effect on the soil is shown, taking into account the types of movers. The authors propose to complete the tractor fleet for various agro-industrial organizations.

Hardy-Littlewood-Type Theorem for Mixed Fractional Integrals in Hölder Spaces

We study mixed Riemann-Liouville fractional integration operators and mixed fractional derivative in Marchaud form of function of two variables in Hölder spaces of different orders in each variables. The obtained are results generalized to the case of Hölder spaces with power weight.

Hardy-Littlewood-Type Theorem for Mixed Fractional Integrals in Hölder Spaces

We study mixed Riemann-Liouville fractional integration operators and mixed fractional derivative in Marchaud form of function of two variables in Hölder spaces of different orders in each variables. The obtained are results generalized to the case of Hölder spaces with power weight.

Sharp Bounds for Generalized m -Linear n -Dimensional p -Adic Hardy-Littlewood-Pólya Operator

In this paper, we study the sharp bounds for the generalized m -linear n -dimensional p -adic Hardy-Littlewood-Pólya operator on central and noncentral p -adic Morrey spaces with power weight. As an application, the sharp bounds for the p -adic Hardy-Littlewood-Pólya operator on corresponding Morrey spaces are obtained. These results generalize substantially some well-known results.

A Novel Multi-Attribute Decision-Making Algorithm for Landfill Site Selection Based on Q-Rung Orthopair Probabilistic Hesitant Fuzzy Power Weight Muirhead Mean Operator

BackgroundWith the rapid development of economy and the acceleration of urbanization, the garbage produced by urban residents also increases with the increase of population. In many big cities, the phenomenon of "garbage siege" has seriously affected the development of cities and the lives of residents. Sanitary landfill is an important way of municipal solid waste disposal. However, due to the restriction of social, environmental and economic conditions, landfill site selection has become a very challenging task. In addition, landfill site selection is full of uncertainty and complexity due to the lack of cognitive ability of decision-makers and the existence of uncertain information in the decision-making process.MethodsA novel multi-attribute decision making method based on q-rung orthopair probabilistic hesitant fuzzy power weight Muirhead mean (q-ROPHFPWMM) operator is proposed in this paper, which can solve the problem of landfill site selection well. This method uses probability to represent the hesitance of decision maker and retains decision information more comprehensively. The negative effect of abnormal data on the decision result is eliminated by using the power average operator. Muirhead mean operator is used to describe the correlation between attributes. ResultsAn example of landfill site selection is given to verify the effectiveness of the proposed method, and the advantages of the proposed method are illustrated by parameter analysis and comparative analysis. ConclusionThe q-ROPHFPWMM operator can describe the correlation between any evaluation factors and effectively reduce the impact of unreasonable evaluation information given by decision makers on the results. In addition, this method has a wider space for information expression, gives the decision maker a great degree of freedom in decision-making.

Design and Performance of a Compact Air-Breathing Jet Hybrid-Electric Engine Coupled With Solid Oxide Fuel Cells

A compact air-breathing jet hybrid-electric engine coupled with solid oxide fuel cells (SOFC) is proposed to develop the propulsion system with high power-weight ratios and specific thrust. The heat exchanger for preheating air is integrated with nozzles. Therefore, the exhaust in the nozzle expands during the heat exchange with compressed air. The nozzle inlet temperature is obviously improved. SOFCs can directly utilize the fuel of liquid natural gas after being heated. The performance parameters of the engine are acquired according to the built thermodynamic and mass models. The main conclusions are as follows. 1) The specific thrust of the engine is improved by 20.25% compared with that of the traditional jet engine. As pressure ratios rise, the specific thrust increases up to 1.7 kN/(kg·s−1). Meanwhile, the nozzle inlet temperature decreases. However, the temperature increases for the traditional combustion engine. 2) The power-weight ratio of the engine is superior to that of internal combustion engines and inferior to that of turbine engines when the power density of SOFC would be assumed to be that predicted for 2030. 3) The total pressure recovery coefficients of SOFCs, combustors, and preheaters have an obvious influence on the specific thrust of the engine, and the power-weight ratio of the engine is strongly affected by the power density of SOFCs.