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Based on the practical experience of power grid planning, the general characteristics and main problems of the receiving-end grid are summarized, and the ideas and methods of external power receiving planning are put forward. Combined with the current situation, the pattern of power supply and demands of a typical recipient power network in China, this paper analysed the reasonable scale of power receiving, the proportion of AC/DC power transmitted and the infeed AC/DC terminal location for long-term development, and conducts comprehensive technical and economic comparisons among various feasible external power receiving schemes to form a recommended scheme

In this study, we used market basket analysis and land accessibility for the layout of MG Steel Logistics Park. Due to the unreasonable cargo space layout, the outbound trucks in the MG Steel Logistics Park detour and transfer, which caused congestion. Using market basket analysis, this research took outbound trucks as the research object to measure the degree of correlation between cargo locations. Then, we measured the convenience of cargo locations by the accessibility and matched it with the steel outbound frequency. We established a model and got the layout allocation plan with the maximum degree of relevance and the minimum difference in cargo-location matching as the target. In the solution algorithm, we use roulette method and the elite retention strategy to improve the genetic algorithm. Finally, we compared the results before and after optimization. We found that the number of truck transfers was reduced by 33%, and the truck staying time was reduced by 21%.

Gust is the most serious natural disaster that threatens the safety of port portal crane. The wind resistance of some port cranes is not optimistic, and wind disaster accidents occur frequently. Based on the analysis of some classic cases of wind disasters at home and abroad, this paper finds out the weak links of the wind proof ability of port portal crane, and puts forward the countermeasures to improve and enhance the wind proof ability of port portal crane.

With the continuous development of modern industry in our country, the use of cranes is becoming more and more common, but the unsafe incidents of cranes occur from time to time, which makes the risk assessment of cranes more and more important. Crane risk assessment has become an important part of crane risk management. In order to further promote the development of crane risk management, this paper tests the feasibility and effectiveness of this method through the study of fuzzy safety evaluation method and the direct application of this method to the risk assessment of portal crane.

Red mud is a strong alkaline waste discharged from the process of alumina extraction, which is harmful to the environment and its utilization rate is always low. One of the effective ways to utilize red mud is used as road subgrade material. In this paper, the industrial wastes including red mud, fly ash, slag, and desulfurized gypsum are used as basic raw materials to prepare subgrade filling materials. A series of laboratory tests, such as compaction test, California Bearing Ratio (CBR) test (soaked and non-soaked conditions) and permeability test, are carried out. The physical and mechanical properties, such as maximum dry density, optimum moisture content, CBR value, expansion, permeability coefficient and soaked strength loss rate, of the mixtures with different proportions, were studied. The results can provide reference for the selection of the best proportion scheme and promote the utilization of red mud in subgrade engineering.

The study of water and heat flux in Aral Sea Basin is a hot topic in the study of water resources in Central Asia. Aerodynamic roughness is the key parameter of inversion. Zom is retrieved based on NDVI and Albedo simulation and verified by the vegetation height in Central Asia. The results show that the inversion of Zom by this model is basically reasonable. In 2018, the monthly average value of Zom is about 0.056m, the vegetation height in Aral Sea Basin is about 0.44m, and both Zom and vegetation height in space are higher in eastern mountainous areas than in western desert areas.

This study documents the occurrence of sulfonamides (SA) and their acetylated metabolite compounds in an aquaculture environment in China. Five parent compounds of SAs and four metabolites were detected in fish water, surface water, and groundwater. The most relevant compounds in terms of frequency of detection and maximum concentrations detected were sulfamethoxazole and sulfachinoxalin in fish water and surface water, with average concentrations of 541 ng/L and 274 ng/L, respectively. The acetylated metabolites were detected at higher concentrations than their parent compounds in groundwater, although they were much lower than in the surface environment. The recent appearance of acetylated metabolites of SAs in groundwater samples demonstrates the environmental health concern and the need of further study.

To solve the problems of cylinder piston striking cylinder and the hydraulic shocking of the main pump, and causing energy waste problem, the method of variable displacement control of piston stroke was proposed. In order to achieve effective control of the piston stroke, variable displacement control model was established under the physical constraint condition of non-collision between piston and cylinder. And the control process was realized by Dynamic Programming(DP), the simulation and test results show that piston of concrete pumping system don’t strike cylinder and reduce the hydraulic shock of the main pump outlet, meanwhile improve the response speed of the cylinder and achieve energy-saving purposes under varying loads. This control model built in the integration design space of structure variable and control variable is of guiding significance for solving open-loop system’s engineering problems.

Silicon carbide (SiC) and gallium nitride (GaN) are typical representative of the wide band-gap semiconductor material, which is also known as third-generation semiconductor materials. Compared with the conventional semiconductor silicon (Si) or gallium arsenide (GaAs), wide band-gap semiconductor has the wide band gap, high saturated drift velocity, high critical breakdown field and other advantages; it is a highly desirable semiconductor material applied under the case of high-power, high-temperature, high-frequency, anti-radiation environment. These advantages of wide band-gap devices make them a hot spot of semiconductor technology research in various countries. This article describes the research agenda of United States and European in this area, focusing on the recent developments of the wide band-gap technology in the US and Europe, summed up the facing challenge of the wide band-gap technology.

This paper describes the technical principles of series compensation, and introduces the series compensation device structure, and finally got through simulation effects of rapid switching Series Compensation for distribution network distance protection. Distribution network is an important network connections and power grid users, from the distribution of electric energy in the power system, the strength of its transmission capacity directly determines the power user power quality is good or bad. However, since the electricity distribution network of long-term failure to get the attention of practitioners, its construction and the relatively slow pace of reconstruction, the aging serious, increasingly unable to meet the annual growth of electricity demand.The main problem with the presence of the grid are:Distribution network construction is lagging behind, power transmission grid capacity is insufficient. Network structure is irrational, power supply radius is too long, circuitous route power line terminal voltage is too low. Part serious aging distribution equipment and lines, the line number is small, backward technology, serious power loss. Reactive power shortage, power grid is not economical and low power quality. Therefore, how to improve the status of the distribution network has become the focus of power workers

The extracellular matrix constitutes a highly organized intercellular medium. In multicellular animals, it plays important functions for cell cohesion and for the modulation of cell differentiation and behaviour as well. All the investigations conducted in non-vertebrate species have shown that the extracellular matrix is present at the onset of the multicellular life and throughout the animal kingdom. The collagen fibrils are the most constant element. Recent data on the structure of fibrillar collagen molecules and on the organization of the corresponding genes, obtained in sponges and sea-urchins have shown the remarkable conservation of these fibrillar collagens during evolution. This even emphasize their very likely fundamental function. These results, associated with data provided by morphological and biochemical informations obtained in cnidarians suggest that these primitive fibrillar collagens are the direct precursors of some vertebrate minor fibrillar collagens such as type V. Other collagens, with interrupted triple helix, are more variable and their characterization in sponges leads to consider these non-fibrillar collagens as precursors of basement membrane collagens, of fibril-associated collagens (the FACITs collagens), of the so-called "epithelial" collagens. They were probably used as sticking devices, anchoring the animal to its substratum, or as covering layers (cuticles, sheaths), and even as skeletons (i.e. the bath sponge). Adhesive molecules of higher animals ensure the mediation of the interactions between cells (via their membrane receptors of the integrin type) and the fibrous network of the extracellular matrix. It is the same situation at the beginning of the evolution of the multicellular animals where fibronectin, tenascin and then laminin are present. Proteoglycans too are components of primitive extracellular matrices. At last, only collagen mineralized by calcium phosphate (in bone) and elastin (in elastic fibers and laminae) seem to be restricted to vertebrates.