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Poverty has long plagued humanity. The main factors affecting the gap between the rich and the poor are natural resources, human resources, information resources and science and technology. Using data from various clean energy industries and historical research methods, this paper shows that the clean energy industry is a new way to reduce poverty in developing countries. In the history of agricultural development, land and water resources are the important sources of wealth growth. In the history of industrial development, mineral resources, coal and oil energy have become the material basis for getting rich. In the 21st century with the great development of artificial intelligence, the importance of power resources is becoming more and more prominent, and clean energy such as solar energy and wind energy has become a new natural resource to create social wealth. Chinese successful practice in the development of clean energy industry shows that the clean energy industry is an effective way to get out of poverty. The results of the cooperation between China and African countries in developing clean energy industries show that the energy industry plays an increasingly important role in helping developing countries out of poverty. Although the development of clean energy industry is still restricted by market competition and monopoly organizations, the development road is still tortuous and long, it has a very bright future.

In this paper, a 2D off-grid small compact model of vertical axis wind turbine was established. The sliding grid technology, the RNG turbulence model and the Coupld algorithm was applied to simulate the unsteady value of the model's aerodynamic performance. Through the analysis on the flow field at difference moments, the rules about velocity fields, vortices distributions and the wind turbine's total torque were obtained. The results show that: the speed around wind turbine blades have obvious gradient, and the velocity distribution at different times show large differences in the computional domain. In the rotating domain vorticity is large. With away from the rotation domain, vorticity reduced quickly. In the process of rotating for vertical axis wind turbine, the wind turbine's total torque showed alternating positive and negative changes.

The US debt limit has important implications for economic and financial stability. By analyzing historical data, this article finds that there is a significant correlation between the debt limit and the US financial market. The article also constructs an exponential smoothing mathematical model to successfully predict the debt limit in the future and test the accuracy of the model using historical data. The results show that the debt limit has a significant positive linear correlation with the S&P 500 Index and the Spot Gold Price Index. Although there is no linear correlation between the debt limit and the dollar index, this paper finds a hidden pattern by comparing the data of the Democratic and Republican administrations. Based on the results of the projections of the debt limit for the next five years and the correlation with the three major indices, the article makes a reasonable prediction of the future trend of the US financial market and provide insights. These results suggest that the situation in the United States may be more optimistic than expected.

In the learning of Chinese as a second language, phonetic learning serves as the basis of the whole learning process, among which the learning of Chinese tones is of paramount importance. In this regard, this paper aims to explore the pronunciation of Chinese tones by native French speakers in the target language environment. First, through the experimental analysis as well as the recording of the tones of native French speakers, this paper selects a total of 237 disyllabic words, with a total of four combinations determined except for the combination of the same disyllabic neutral tone in the target language environment. Meanwhile, this paper utilizes PRAAT software to acquire the average frequency of tone sampling points, whereby the tone-pattern error of each tone combination can be clarified. Secondly, by comparing and analyzing the foregoing results with the tone patterns of Chinese students, this paper further finds out the tone-pattern errors of the same tone combination in disyllabic words, thus summarizing the corresponding error rules. Through the above experimental analysis, this paper concludes that the combination of Tone 3 and Tone 3 presents the highest pronunciation error rate, followed by the combination of Tone 2 and Tone 2. In addition, this paper reveals that the tone error is the main tone error and that there are also duration errors. Lastly, combined with the specific reasons for the errors, this paper proposes targeted online teaching strategies suitable for international Chinese education.

In the fabrication of silicon wafers to create integrated circuits, chemistry and physics play a significant role. It is important to change the silicon wafer surface conditions and properties using both innocuous and harmful compounds, particular and uncommon circumstances, plasma-state elements, and RF (Radio Frequency) energies. Starting with the production of silicon wafers, sands are molten under high temperature in order to change its molecular structure. In this process, silicon ingot with particular diameter is formed and sliced into pieces of wafer. Following by chemical manufacture, wafer would be prepared to be fabricated into integrated circuits. Then, the circuits would be drawn onto the wafer through oxidation, photolithography, etching, diffusion, and ion implanation. After those fabrication, all these components (transistors, resistors, capacitors, and so on) were only accessible as discrete units, would have taken up most of a medium-sized room 20 years ago, the devices currently fill a one-inch square IC’s surface. When it comes to wafer sorting, a systematic mode will be used to take each bad die from the whole die pie. The researchers will use the relative finder and tester to gain the situation for each die and this work will bring foundation to the following stages including packaging and final test. The packaging process comes to the next consideration. This work divides the packaging process into five steps. All those steps are listed clearly in the essay below, from sawing up the wafer into an individual die to marking the packages. The final process after packaging is the final test. The final test is not such complicated. So this work only introduces the devices that it will use and its purpose.

Composite materials have been widely studied due to their good mechanical, electrical and chemical properties, especially atomic structure fuel cells with large specific surface area, high electrical conductivity and good compatibility of composite materials. These new composite materials have many excellent physical and chemical properties, and are widely used in many fields, especially in the field of electrochemistry, showing their unique advantages. Composite materials play an important role in the electrocatalytic reaction of composite materials due to their high specific surface area and good compatibility of composite materials. The construction based on composite materials has high sensitivity, wide linear range, good repeatability and stability. As a catalyst in a fuel cell, the composite material can improve the energy density and fuel utilization rate of the fuel cell, which is a high-performance fuel cell.

With the advent of the Internet society, gender stereotypes have gradually become more binding for women, and there are gender stereotypes or feminist theories spreading in both the real society and online media. This article is beneficial to the study of current feminism and the discussion of women’s discourse on the Internet. By applying the theory of gender stereotypes and taking bloggers’ postings on Red Book as the research object, this article analyzes the reasons for the emergence of white, thin and young as the main aesthetic theme, as well as the reasons for the gradual dissipation of this stereotype and its effects. The results of the study show that with the large number of current social media users and their rapid dissemination, the mainstream aesthetic finds changes from the gender stereotype of white, thin and young to its dissolution, reflecting the contemporary mainstream view that women are no longer objects to be gazed at and objectified. This study further demonstrates that social media has an important role in promoting the development of feminism in China and that the influence and changes produced by women’s opposition to stereotypes have promoted more women to embrace a pluralistic aesthetic.

The paper combined with the actual situation of setting up outdoor swimming pool facilities in the school analyzes and studies the design content of the preliminary positioning, engineering design, construction design and operation use from the positioning, design, cost, energy saving, management, operation and other aspects of the transformation concept of “planning” and “construction”, and provides a reference for the design of the outdoor swimming pool in the school.

Heating methods adopted in Northern China’s rural areas show characteristics of diversity, low heat efficiency, bringing environmental pollution and so on. Meanwhile, with harvest in rural areas, there has been a problem of a large amount of accumulated waste straws which can be used as biomass energy, a source of clean energy and also green energy of the 21st century given its fraction of harmful components such as sulfur, nitrogen and heavy metals.

For the highway bridges with small or medium span, a vehicle will stay on the bridge after the excitation. So the measured values of the vibration characteristics of the bridge are related to the vehiclebridge system. In order to analyse the natural vibration characteristics of simply supported bridge and the loaded frequency of vehicle-bridge system, theoretical analysis was carried out firstly, then the simply supported beam calculation model was built based on finite element method, and the results were compared with the measured values. The finite element model of a mass block-simply supported beam system was built by regarding the vehicles as a concentrated mass block attached. Both the vibration modals of the bridge system and the loaded frequencies of the vehicle-bridge system under diffident vehicle positions were obtained by software analysing. As a result, the variation characteristics of the loaded frequency for this simply supported bridge were extracted and discussed through the comparison of the results from both finite element method and the measured.

Energy demand forecast has an important practical significance for the sustainable development of the national economy, the reasonable allocation of resources, and the construction of modernization goals. This study is based on the analysis of coal, electricity, natural gas, and other energy data in Yunnan Province from 2011 to 2018 and uses long short-term memory, sequence to sequence, deep learning, and ridge regression coupling methods to construct an energy demand forecast model in Yunnan Province. Forecast results show the following. The total energy consumption of Yunnan Province from 2021 to 2025 will continue to increase. Moreover, the coal consumption of Yunnan Province will continue to decline from 2021 to 2025. Furthermore, the electricity consumption of Yunnan will increase by about 8.02% year-on-year from 2021 to 2025. The experiment proves that the forecasting effect of the energy demand forecast model proposed in this study is excellent.

The offshore engineering develop fast in recent years, a new method named “big-size sandbag cofferdam” is applied to many practical projects in China. The sandbag is made of geotextile with large sizes in length and width. Sandbags are filled with pumped sea sand and stacked together layer by layer. Many theoretical obstacles remain unsolved, which has restricted the application of this advanced technology. Based on an instability project located in Bohai Bay, the failure mode of the big-size sandbag cofferdam on soft foundation was studied. The results show that the deformation of cofferdam was concentrated on the bottom sandbag, under the action of insufficient foundation bearing capacity and overburden load, the stress of the geotextile at the bottom layer increase sharply during the fast filling, then exceed its ultimate tensile strength, and the cofferdam would be pulled apart from the bottom to top, lead to a continuous penetrating sliding surface failure of big-size sandbag cofferdam.

Substantial produced water in oilfield need to be treated. Treatment mechanism such as adsorption, flotation, filtration, desalination, etc. are described. Based on the mechanisms, process and technology, tools and facility for produced water treatment are compared. Technology selection method and requirements are discussed. Multiple processes combination is discussed and considered as promising.

In this paper, the simulation analysis on partial discharge (PD) signals produced by multiple insulation defects in gas insulated substation (GIS) has been researched by the simulation software of electromagnetic field (XFDTD). The theoretical analysis and simulation results show that the single partial discharge signal is the linear convolution of the partial discharge current signal and its corresponding impact response in GIS. The mixed partial discharge signals are the linear mixtures of every partial discharge signal.

Depression is an affective disorder that endangers human health, and its main clinical feature is significant and persistent depression. The pathological mechanism of depression is complex and has not been fully elucidated so far. In recent years, with the further study of molecular biology techniques, depression is closely related with mood regulation, cognitive function, function changes of specific protein and abnormal cell signal transduction pathways in the brain, causing cell dysfunction, which affects the brain nerve cells apoptosis regeneration mechanism of trigger depressive symptoms. By referring to and sorting out relevant literatures, this paper comprehensively described the research progress of the signal transduction mechanism of cyclic adenosine phosphate (cAMP), mitogen-activated protein kinase (MAPK) and calmodulin kinase (CaMK) in depression, so as to provide reference for explaining the pathogenesis of depression and developing treatment plans.

The optimal synthesis process conditions of polycarboxylic acid water reducers were investigated and characterized by infrared spectroscopy as well as GPC using high performance polycarboxylic acid water reducers synthesized by isoproterenol polyoxyethylene ether polymerized with acrylic acid and introducing unsaturated monomeric dibasic ester. The results showed that the optimum synthetic process conditions were as follows: acid-ether ratio of 3.0:1, amount of binary ester as 2.8% of monomer mass, amount of initiator as 0.35% of monomer mass, amount of chain transfer agent as 0.35% of monomer mass; the initial slump and initial expansion of the concrete of the synthetic water-reducing agent PCE-H were greater than those of the commercially available polycarboxylic acid water-reducing agent PCE-W, and the working performance of the concrete was better. PCE-H also has no adverse effect on strength.

The physicochemical properties of Phellinus baumii polysaccharides extracted from the fruiting bodies by different grinding methods were studied in this paper. Compared with ordinary grinding methods, superfine grinding technology exerts significantly higher yields of crude polysaccharides, polysaccharide contents and β-Glucan contents of six samples. HPSEC-MALLS- RI analysis shows the molecular weight distribution of P.baummii crude polysaccharides, which indicates superfine grinding technique generates higher molecular weight fractions and larger polydispersities. The 6 kinds of crude polysaccharides have obvious effects on NO generation of RAW264.7 cells, which indicated that crude polysaccharides from P.baumii may have some immune-enhancing effects. Meanwhile, CW30 and FP30 show the best immune enhancing effects. However, CW50 and CW70 exert weaker immune-enhancing effects compared with FP50 and FP70.

Assembled steel pipe pile, which is a novel pile foundation, is developed in the paper. The ultimate uplift bearing capacity of the pile is proposed, and simulation by Plaxis3D and the corresponding experiment are performed to verify the theory. In the simulation, ultimate uplift bearing capacity of the assembled steel pipe pile and ultimate lateral frictional resistance of the interface of pile-soil increases with the increasing of the strength and stiffness of the interface of pile-soil, and with the increasing of length-diameter ratio, ultimate uplift bearing capacity of the assembled steel pipe pile increases while the ultimate lateral frictional resistance decreases gradually. The ultimate lateral friction is influenced by both of the strength of the soil around the pile and the interface of pile-soil, and the ultimate uplift bearing capacity obtained by simulation and theoretical calculation are close. Long-gauge FBG sensors are used in the experiment for measuring the longitudinal strain of the pile, and the error of ultimate uplift bearing capacity between the results of experiment and theory is less than 10%.

Image measurement technology has been widely used in monitoring the deformation of the soil field around the pile with its advantages of no damage, no contact, full-field measurement, no added quality and high sensitivity. But there are few researches on image-based bearing deformation measurement of the pile. Through an indoor pile-soil semi-model test, the rigid body displacement and load-bearing deformation of a new type of prefabricated steel tube pile foundation under horizontal load was measured based on image features. In this study, the concept of optical extensometer is first applied to the measurement of local average strain of a non-uniform deformed structure. Based on an improved feature point tracking algorithm SURF-BRISK, non-contact measurement of tiny strain of pile body is realized. In addition, based on DIC technology, this study also obtained the progressive development of displacement field of soil around pile. The above work fully reflects the non-contact convenience and full-field richness of the optical measurement method compared with the traditional measurement method.

The contact performance of various mechanical parts has important influence on the static, dynamic and motion response of mechanical equipment. The characterization of rough surface topography is the basis for the study of friction, wear and contact deformation between mechanical bonding surfaces. By analyzing the various models of the characteristic parameters of mechanical interface, we provide a systematic research idea for the model of mechanical joint surface in the future. For further details on rough surface profile, the G-W model is put forward. Then the M-B model perfects its lack of scale independence. The relationship between actual contact area and load is derived from the M-B model based on fractal geometry theory. These formulas are used to study the characteristic parameters of mechanical interface, and the fractal model of contact damping and loss factor is established. Since fractal parameters are not limited by sampling length and resolution of measuring instrument, the new models are more reasonable than before. However, just as the M-B model needs to be improved, the model based on this need to be further studied, and the application of the model also needs to be explored more.

Based on the static equilibrium model of mooring system parameters, the multi - objective optimization model is established and the genetic algorithm is introduced as the optimization algorithm, which improves the crossover operator. Taking the example of a single point mooring system, concerned optimization design and calculation has been done. Compared with the general genetic algorithm, the result of this algorithm is superior, significantly improving the stability of the mooring system.

Zn-Al-Mg alloy coating attracted much attention due to its high corrosion resistance properties, especially high anti-corrosion performance at the cut edge. As the Zn-Al-Mg alloy coating was usually produced by hot-dip galvanizing method, solidification process was considered to influence its microstructure and corrosion properties. In this work, a Zn-Al-Mg cast alloy was melted and cooled to room temperature with different solidification processes, including water quench, air cooling and furnace cooling. Microstructure of the alloy with different solidification processes was characterized by scanning electron microscopy (SEM). Result shows that the microstructure of the Zn-Al-Mg alloy are strongly influenced by solidification process. With increasing solidification rate, more Al is remained in the primary crystal. Electrochemical analysis indicates that with lowering solidification rate, the corrosion current density of the Zn-Al-Mg alloy decreases, which means higher corrosion resistance.

The tractor-semitrailer model is general described and analyzed in road reference coordinate system. The lateral error of look-ahead distance has been chosen as nominal plant and a robust controller using H∞ loop-shaping procedure is designed which can ensure the maximum stability margin meet the performance requirements. The results show that the controller can make the tractor-semitrailer stable under perturbed conditions and can guarantee the look-ahead lateral offset keeping in the specified scope proposed. The target of lateral control is satisfactory.