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This study presents a Finite Element (FE) simulation model for Single-Point Incremental Forming (SPIF) of a panel part using AA5754 Aluminium Alloy. The precision of model was highly enhanced through experimental data integration by uniaxial tensile tests (UATT) to determine material flow stress and anisotropic properties. The Voce model accurately predicted material flow stress within a 5% error margin, and equations were concluded to convert Lankford coefficients (R-values) into anisotropic stress ratios for Abaqus/Explicit simulation. Experimental validation demonstrated a close agreement in major strain and thickness distribution, with a maximum error below 5.8% across high and low forming speeds.

The long-term vibration of the carbon canister during vehicle operation can lead to changes in its performance, thereby affecting its performance on evaporation emissions. A vibration test bench simulating vehicle vibration characteristics is used to simulate the working state of the carbon canister under actual driving conditions, analyze the amount of carbon powder precipitation and flow resistance changes in the canister after long-term operation, and compare the adsorption and desorption performance of the canister before and after aging and their effect on the evaporative emissions. The results showed that the carbon canister will produce carbon powder precipitation after being continuously subjected to the forward and backward vibration of the vehicle. This leads to a decrease in the ultimate adsorption and desorption capacity of the aged carbon canister for fuel vapor, with a more significant decrease in adsorption capacity. However, in the 2-day Diurnal Breathing Loss(DBL) test, due to the increase in flow resistance of the aged carbon canister, it is more difficult for the adsorbed fuel vapor to diffuse outward. For the unsaturated carbon canister, fuel leakage and evaporative emissions can be reduced. In evaporative emission management, it is necessary to adjust the control strategy reasonably based on the working status of the carbon canister.

Volatile Organic Compounds (VOCs) significantly threaten the atmospheric environment. Currently, common methods for the recovery and treatment of VOCs include adsorption, solution absorption, photocatalytic oxidation, and high-temperature oxidation. Among them, the Regenerative Thermal Oxidizer (RTO) is a scheme for high-temperature oxidation treatment of VOCs, which applies aerospace heat transfer and combustion technology to the treatment of VOCs, and the removal efficiency of VOCs can reach over 99%. Considering the high temperature and possible instantaneous overpressure during the combustion process, a three-dimensional flow model of the bottom air distribution chamber and heat storage chamber was established to solve the technical difficulties of the gas flow field in the existing RTO and improve the safety and stability of the overall flow. Simulated the gas flow field and analysed the distribution pattern of the gas flow rate. In response to the uneven distribution of airflow caused by the pipeline layout, orifice plates were installed at the bottom of the furnace, and various orifice plate designs were considered. The results indicate that adding slanted orifice plates can improve flow conditions and enhance safety while meeting practical needs.

In the context of high-quality development of senior care services, public-private-run senior care institutions are a new type of senior care institution operation mode, which integrates the advantages of traditional public and private senior care institutions, circumvents the drawbacks of the two, and provides a new path choice for alleviating the diversified senior care needs of the elderly. By analyzing the internal and external advantages of the development mode of public-private elderly care institutions, as well as the threats and challenges faced in the development process. The study found that public-private elderly care institutions have the advantages of integrating elderly care resources and tending to be more specialized and diversified, but public-private elderly care institutions are also vulnerable to profit-driven, deviating from the positioning of public welfare; the lack of professional talents and other problems. The strategy of integration of industry and education should be further implemented to ensure the supply of professional nursing talents; strengthen the government's supervision and management, and establish a mechanism for the exit and introduction of public-private elderly care institutions. Further optimize the operation mode of public-private elderly care institutions, provide diversified choices of elderly care services, and help the high-quality development of elderly care services.

Reduction of greenhouse gas (GHG) emissions for mitigating climate changes is globally necessary. As a major GHG emitter, refinery sector is responsible for 14.1% of China’s CO2 emission in 2019. The flue gas associated with petroleum refining has high CO2 content, presenting potentials for methanol and electricity co-production when the methane and hydrogen in dry gas are considered. To unlock the green opportunity for refineries, in this study we employed Aspen Plus to develop the process of methanol synthesis by recovering CO2 in the flue gas of fluid catalytic cracking (FCC) unit and the methane and hydrogen in dry gas. The results show that the new co-production process increases the energy efficiency of the FCC unit by 2.4%. Compared with traditionally natural gas-based methanol production, the developed process enables annual CO2 mitigation of 1.3 million tons.

Engineering chemistry is the basis of materials science. Students majoring in materials specialty should learn engineering chemistry well and closely link it with materials science. However, it is difficult to achieve the expected teaching effect in the actual teaching process. By analysing the problems existing in the traditional teaching process of engineering chemistry, this study proposes a teaching strategy based on the BOPPPS teaching mode, such as the introduction of the flipped classroom and the classroom Interaction to enhance the interests of students in learning and their self-efficacy, so as to enrich their specialized knowledge and develop their creative thinking and abilities.

In order to adapt to the latest development of higher education in the era of big data, improve the sensitivity for postgraduate of chemical engineering in the public opinions of public events related to their major, this study took “the pandemic of COVID-19 on Twitter in Germany” as an example and investigated the health communication and public opinions on COVID-19 based on the Python scripts and Twitter streaming application programming interface using statistical analysis and chi square feature selection. The provided method is helpful to improve the insight, prediction, scientific literacy and innovation ability of postgraduate of chemical engineering.

Under the background of ideological and political education in the curriculum, according to the requirements of talent training in applied universities, the authors take the analytical chemistry curriculum as the implementation carrier of ideological and political education. Taking case teaching as an innovative means, a teaching case with EDTA as coordination titrant was designed. Based on the explanation of the principle that metal ions and coordination atoms coordinate to form stable compounds in Lewis acid-base theory, the ideological and political education was effectively combined with the teaching point of analytical chemistry knowledge, and the reason why EDTA had wide adaptability was proposed. From the perspective of ideological and political education, the teaching designs carried out with values education as the main line. The curriculum not only imparted professional knowledge, but also guided students' values. A reasonable teaching design can realize the educational goal of the same frequency resonance between professional courses and ideological and political education.

Chemistry is an experimental science. Practical teaching is a significant link in the cultivation of students majoring in chemistry to foster students' practical, professional application, and innovation abilities. Based on the investigation and analysis of the problems existing in the cultivation of the practical ability of applied chemistry major, take specific measures, such as constructing the practical teaching system of applied chemistry major, explored a better practical teaching system for students of applied chemistry major; applied to the reform and innovation of training mode of students majoring in applied chemistry and achieved good results.

By combing the constitution of 7 private colleges and universities in Zhejiang Province, this paper summarizes the law of internal governance of private colleges and universities, analyzes the structure and characteristics of internal governance of private colleges and universities, and puts forward some thoughts.

Mitigating greenhouse gas (GHG) emissions to curb climate change has become a consensus among international community. Refining is one of the major industries with high energy consumption and high emissions, which is responsible for 4-10% of global carbon dioxide (CO2) emissions and approximately 25% is generated by fluid catalytic cracking (FCC) units. The flue gas discharged from FCC units has a high CO2 content, presenting potential for methanol and electricity co-production production when the methane in the dry gas is considered. To unlock this green chance for enterprises, we designed a methanol production system that uses the CO2 recovered from the flue gas of fluid catalytic cracking (FCC) unit in a refinery and the CH4 separated from dry gas as feed stock (hydrogen to be added from an internal hydrogen production unit of the refinery). We analyzed economic feasibility of the process, the results show that the developed system is economically feasible for annual methanol yields of 1.0-2.5 Mt and the internal rate of return increases by 8.3%.

The initial distribution of gas and liquid is one of the key factors that determine the operation efficiency of packed towers. The development of a gas distributor for ultra-large air blow-out bromine extraction plant can improve operation efficiency, save energy and reduce consumption. In order to develop the gas distributor for ultra-large air blow-out bromine extraction plant, the guidelines for evaluating gas distributors are clarified in this paper, and six kinds of commonly gas distributor are compared in detail. Considering gas distribution inhomogeneity, liquid foam entrainment rates and distributor pressure drop, the double tangential circulation type gas distributor is the first choice in the ultra-large air blow-out method bromine extraction plant.

As one of the major energy-consuming and high-emission industries, the refineries account for 10% of global industrial carbon emissions, of which about 25% is emitted by fluid catalytic cracking (FCC) process. Therefore, CO2 capture from FCC flue gas create the possibility for low-carbon refineries. We developed a novel CO2 utilization process to methanol production modeling using Aspen Plus. Meanwhile, organic Rankine Cycle (ORC) power generation technology was coupled to recover the waste heat of the system. A five-million-ton FCC unit in China was selected as a case study. We conducted some analysis for the process, the results show that the developed system boosts the energy efficiency of the FCC unit by 2.8%. The annual capacity of the waste heat power generation unit is 4.8 GWh, with a thermal efficiency of 5.9%.

Under different transmission mechanisms, major public health emergencies have different effects on economic growth. Based on the specific economic impact of COVID-19, a literature analysis method was used to systematically explain the economic impact of different channels and specific transmission mechanisms caused by major public health emergencies. Major public health emergencies caused serious damage to life and health, and had a huge impact on the entire economic environment. However, different economic sectors have different levels and channels of impact from the pandemic. The existing literature has analysed the various impact mechanisms of major public health emergencies on the economic development process from many angles, but there are still problems that need in-depth discussion and supplementary research.

The educational informatization ability of English major normal school students is the endogenous variable that drives the reform of English education system, and it is also the key to drive the development of education modernization. Training and improving the educational informatization ability of English majors is a brand-new ability requirement under the information technology. In order to better adapt to the new teaching environment and improve the effectiveness of education, based on the characteristics of English major and the basis of students, the system of cultivating the educational informatization ability of English major normal school students should be constructed by integrating the information technology background. Based on the background of the application of information technology, this paper puts forward some strategies for the construction of the educational informatization competence training system for English majors.

In information war, the concept of “digital battlefield” is put forward, and battlefield meteorological and marine information has become an important part of digital battlefield. Based on the in-depth analysis of the impact of meteorological marine information on cruise missile, this paper puts forward the multi-dimensional demand analysis method of meteorological marine information supporting cruise missile combat application and the architecture design method based on MBSE, and gives the conceptual design framework of combat application system to provide information support for cruise missile combat application.

Telemetry image has the characteristics of intuitive image in the process of rocket flight. Through real-time acquisition of rocket flight video image, it can provide the working status of key nodes in the process of rocket flight, and provide intuitive decision-marking auxiliary information for commanders. This paper analyzes the design content of the image processing system of the space launch site from the aspects of image transmission mechanism, information flow, image data processing and image decoding, so as to provide technical basis for the image receiving, transmission and decoding process in the engineering practice of the image processing system.

To detect the operating condition of equipment and understand the environmental management situation of enterprises in real-time, this paper studies the non-intrusive load decomposition of enterprises based on bidirectional LSTM. In this paper, we first obtain the load characteristic parameters of different equipment in different states, and then obtain the electrical power measured from the main power meter of decontamination equipment in TOP-5 through the softmax layer of bidirectional LSTM, and then change the softmax layer to decompose the load data from the main power meter.

This paper takes the piano industry of Deqing County as example, under the framework of technological innovation and industrial transformation and upgrading model, demonstrates from four levels including technology, talents, entrepreneurs and government behavior, and analyzes the difficulties and suggestions of technological innovation and industrial transformation and upgrading.

The double-blade half-rotating impeller tidal turbine (DHITT) is a new type of vertical shaft tidal current turbine with lift and resistance performance. The power coefficient of the DHITT is affected by the flow direction. In order to research the power coefficient (CP) of the DHITT under different flow direction, the optimal attack flow angle of a half-impeller turbine was explored, and the fluctuation of power coefficient of the DHITT operating at yaw was analyzed based on the optimal attack flow angle. The unsteady flow of the turbine was simulated by overlapping grid technique, and the fluctuation of the turbine’s power coefficient under different flow directions was analyzed, which was verified by experiments. The results have demonstrated that the power coefficient at the optimal angle of attack is 0.53. As the yaw angle greater than 30º, the power reduction is nearly 40%, but the average efficiency loss is only 3.7% in the range of -3º to 3º.

With the continuous and rapid development of the national economy and the improvement of people's living standards, the construction of regional power grids is gradually increasing, and the corresponding investment will also increase. If the scale of investment is too small or lagging, it will inevitably fail to meet the requirements of economic and social development and load growth. It will also affect the long-term development of the enterprise and fail to achieve the expected investment benefits. However, if the scale of investment is too large or too advanced, it will inevitably cause waste of funds and excess resources, and will also cause business pressure. Therefore, it is necessary to carry out input-output efficiency evaluation research on regional power grids to determine whether the scale of power grid construction is appropriate and whether the input and output match. Therefore, this paper uses the DEA input-output theory, combined with the analysis of the actual asset investment objectives of power grid companies, to build a comprehensive input-output evaluation system, and optimally conduct empirical analysis based on the actual data of various units in a certain area, which can provide support and guide.

In the face of the increasing scale of port video surveillance systems, edge computing is gradually used to improve the real-time processing efficiency of surveillance systems and reduce the load on the cloud with the advantages of distributed computing. In order to improve the security factor of terminal access in the edge computing environment, this paper proposes a decentralized terminal security access authentication system based on blockchain, which realizes the identity registration, revocation and mutual authentication of two interfaces between terminal devices and edge computing through the smart contract technology of blockchain, and establishes a trusted channel for data transmission between terminals and edge nodes. Through the functional test of the system and the security analysis of the system on the Hyperledger Fabric platform, it shows that the system has more security attributes and higher security.

UAV (Unmanned Aerial Vehicle) has broad application prospects in various fields. In order to meet the needs of stability and efficiency during flight, a surface-mounted permanent magnet synchronous motor is used as its rotor motor, and a position sensorless control technology is used to control the rotor motor with high efficiency and high dynamic response. This paper proposes a position sensorless control strategy in the full speed range for the actual application requirements of UAV. In low speed ange, I/F control strategy with speed-open-loop and current-closed-loop is. In medium and high speed range, a sliding mode observer is adopted to provide estimated rotor position and speed. To achieve smooth switching from I/F control stage to speed closed-loop stage, a switching algorithm is proposed. The feasibility of the proposed hybrid control strategy is verified by simulation results.

Quality education is one of the pillars of UN sustainable development. The proposition was pointed out by General Secretary Xi Jinping at the National Conference on the University Ideological and Political Work that “Universities and colleges should be based on the moral and talent cultivation”. It was required to take the idea of “Moral and Talent Cultivation” as the university guiding idea and coordinate the development of all kinds of university work, starting from the university ideological and political work. Therefore, under the guidance of the idea of “Moral and Talent Cultivation”, this paper is aimed to construct a collaborative innovation system of the university ideological and political education with the whole curriculum, the whole process and the whole-staff cooperation so as to realize the comprehensive education.

Construction dust falls to the snow cover and the surface of the glacier to form a fouling layer to absorb more solar radiation and reduce the intensity of surface albedo, thereby accelerating the melting of the glacier, which is the main factor affecting the glacial environment in the Highway construction. This article adopts the combination method of wind tunnel experiment and numerical simulation was used to calculate the impact range of construction dust. The results show that with increasing of particle size, the diffusion range of dust decreased while the settlement speed increased. High dust concentration area (> 4mg / m3) is generally distributed within 1000m around the construction site. The specific extension direction is directly related to the local terrain and wind direction, and the height direction is generally not more than 300m. According to the above simulation results, for preventing and reducing the impact of highway construction on the glacial environment, the requirements of route selection and construction dust control measures was put forward, which played an important role and significance in guiding the highway design and construction and reducing the impact of highway construction on the glacial environment.

In recent years, natural polymer coagulant has become a hot spot in the field of coagulants due to its safety, harmlessness and biodegradability. This paper introduced the status quo of research of natural polymer coagulants such as starch, chitosan, cellulose and lignin coagulants. And some hot applications in water treatment were discussed, such as heavy metal wastewater, dye wastewater, microalgae collection and sludge dewatering. Finally, the development trend of natural polymer coagulants was prospected.

Rapeseed and sunflower meal are mainly used as animal feed but they can also be considered as a potential source of bioactive phenolic compounds. However, the desolventization/toasting processes that are needed to produce these meals might influence concentration and chemical structure of phenolic compounds, and change their bioactive properties. Moreover, the recovery processes of these molecules from meals are based on the use of solvent that generates effluents and might affect the integrity of the other constituents of the meals. Knowing this, the PHENOLEO project, funded by the SAS PIVERT, was a research program based on the biorefinery of rapeseed and sunflower meals that aimed to develop new routes of valorization of these materials mostly by the separation and valorization of their simple phenolic compounds. Thus, we decided to focus this study on the impact of the desolventization process on the biochemical composition of meals, the separation process of their simple phenolic compounds, the production of phenolic acids from meals and the potential valorization routes of the phenolic fraction.

Currently, the world is confronted with a series of challenges including resource shortage, climate change, environment pollution and energy poverty, which are rooted in the humanity’s deep dependence on and large-scale consumption of fossil energy. To tackle with those challenges is an urgent task for realizing sustainable development. The Global Energy Interconnection (GEI) is a clean energy-dominant, electricity-centered, interconnected and shared modern energy system. It is an important platform for large-scale development, transmission and utilization of clean energy resources at a global level, promoting the global energy transition characterized by cleaning, decarbonization, electrification and networking. The GEI has provided a scientific, novel and systematic solution to implement Agenda 2030 as well as the Paris Agreement. Focusing on the scope of clean transition and sustainable development, this paper has implemented qualitative and quantitative methods based on historic data. The global power demand and supply has been forecasted. Based on global clean energy resources endowments and distribution, a global main clean energy bases layout and generation planning optimization has been proposed. Later in this paper, the global power flow under the GEI scenario and corresponding GEI backbone grid has been explored and proposed. Finally, based on a preliminary investment estimation, the comprehensive benefits of building the GEI have been analyzed.

The guided waves in the elbow was analyzed using semi- analytical finite element method, which was used to calculate the dispersion curves, along with the vibration deformation and energy flow density distribution of the elbow cross-section. The L(0,1) mode guided wave was used to detect different defects in the U-shaped pipeline in experiment. The average experimental velocity of L(0,1) mode in U-shaped pipeline was between the theoretical velocities of the straight pipe and the elbow, due to the different velocities in the two parts. The detection sensitivity difference of L(0,1) mode guided wave to defects in intrados and extrados of the elbow was analyzed, the experimental result showed that the reflected signal amplitude of defect in extrados was significantly larger than the defect in intrados, which was consistent with the energy flow density distribution in elbow cross-section.

Whether the energy metering device is accurate or not is related to the economic interests of both the division and sale of electric power, but in reality, energy metering device failure is inevitable. When a failure occurs, it must be certain of the correct way to calculate the accrued power. Classic methods of electricity are estimated by returning and adding “correction coefficient”, but the fault characteristics of electronic table differs from previous induction meter. Electrical parameters and the cumulative power is erratic, leading to “correction coefficient method” failure. This paper describes a means of electrical parameter automation metering systems continuously recorded using the thought of “integration”, the correction coefficient to compensate for the lack of power to solve real projections fault electronic energy meter problem.

As an important method for solving boundary value problems of differential equations, the finite element method (FEM) has been widely used in the fields of engineering and academic research. For two dimensional problems, the traditional finite element method mainly adopts triangular and quadrilateral elements, but the triangular element is constant strain element, its accuracy is low, the poor adaptability of quadrilateral element with complex geometry. The polygon element is more flexible and convenient in the discrete complex geometric model. Some interpolation functions of the polygon element were introduced. And some analysis was given. The numerical calculation accuracy and related features of different interpolation function were studied. The damage analysis for the koyna dam was given by using the polygonal element polygonal element of Wachspress interpolation function. The damage result is very similar to that by using Xfem, which shows the calculation accuracy of this method is very high.

A new cationic asphalt emulsifier of N,N-dimethyl-N-(3-(N',N'-dimethyl amido)-2-hydroxy propyl)- coconut oil amide propyl-1-ammonium chloride was synthesized by two steps reaction of coconut oil acyl propyl dimethyl tertiary amine (PKO), epoxy chloropropane and dimethylamine. The chemical structure of the key intermediate of N,N-dimethyl-N-(ethylene oxide-2-methylene)-coconut oil amide propyl-1-ammonium chloride was confirmed by FTIR, 1H NMR and elemental analysis. The optimum reaction condition of first step was obtained by single factor analysis: reaction time 5 h, reaction temperature 50 °C, feedstock mole ratio of epoxy chloropropane to PKO 1.05. The reaction yield is 82.15% and the epoxy value is 40.39% at the optimum conditions. The critical micelle concentration (CMC) of the asphalt emulsifier is 7.80×10-2 mol/L. The surface tension at CMC is 24.57 mN/m. The emulsifier showed excellent emulsification effect for the asphalt. The prepared bituminous emulsion had higher storage stability. The emulsifier belongs to medium-set asphalt emulsifier.

In this paper, the researches and the application of manhole over as well as the existing problems have been described. The mechanical security code manhole cover with the built-in locking mechanism has been designed. The locking mechanism can withstand the muddy water immersion test, the password design test, the low temperature alternating cycle test, the failure load test and the vibration test. The manhole cover is equipped with an electric key and a mechanical key. The electric key automatically opens the code lock by receiving the password. The mechanical key demands to manually adjust the dial to open the code lock. The key and the password are respectively managed by different people.

High pressure water abrasive jet nozzle is key part of the particles acceleration. The diameter of nozzle has important effect for jet fluid. Through experiment and simulation explore the relationship between nozzle diameter and jet fluid cutting capacity. The result indicate: ①the cut depth and broad reduced in linearly relationship with the diameter of the jet nozzle. ②In same pressure, decrease the nozzle diameter will reduce the cutting ratio energy; ③The acceleration and attenuation of the nozzle axial flow in different diameters are basically consistent, The smaller nozzle diameter, The flow acceleration will slower, the attenuation will faster, the is velocity core segment will shorter and the cutting ability will lower;Consider from energy consumption, cutting efficiency and other factors, for common material cutting the nozzle preferred diameter is: 0.6~1.0mm, it’s unfavourable to select the 0.2mm diameter

The conventional air vessel installation is usually installed behind the check valve at the upstream end of the pipeline to effectively control the water hammer pressure due to pump trip. However, the water hammer pressure caused by underground pipe burst has been neglected. The water hammer protection of air vessel due to pipe burst in long distance water supply system was discussed in this paper. According to analysis of the process of the pipe burst, the mathematical model of underground pipe burst and air vessel were established. A new air vessel installation that was installed in the middle of the pipeline was proposed. The new air vessel installation was simulated by method of characteristics. Then it was compared with the conventional air vessel when the pump trip and the pipe burst occur respectively. The results show that both the conventional air vessel and the new air vessel can effectively protect the water hammer duo to the pump trip. Moreover, when pipe burst occurs, the conventional air vessel cannot achieve the safe operation of the long distance water supply system. However, under the same air vessel type parameters, the new air vessel installation can effectively protect the water hammer pressure.

The existing method for investigating the subsynchronous resonance (SSR) caused by wind powergeneration is mainly aimed at a deterministic condition. In order to analyse the impact of uncertain factors onSSR in wind farms, this paper defines the risk matrix and risk index, and develops a SSR-oriented riskassessment method of using probabilistic collocation method (PCM). Considering the uncertain of windspeeds, the proposed method is used to assess the SSR risk of a wind farm. The results show that under thesame wind speed distribution, the higher the series compensation level in the system is, the greater the SSRrisk of the system could be; under the same series compensation level, the SSR risks caused by different windspeed distribution are different, and the system in the areas with lower average wind speed obtains greater SSR risk.

Abstract The Sox gene family is found in a broad range of animal taxa and encodes important gene regulatory proteins involved in a variety of developmental processes. We have obtained clones representing the HMG boxes of twelve Sox genes from grass carp (Ctenopharyngodon idella), one of the four major domestic carps in China. The cloned Sox genes belong to group B1, B2 and C. Our analyses show that whereas the human genome contains a single copy of Sox4, Sox11 and Sox14, each of these genes has two co-orthologs in grass carp, and the duplication of Sox4 and Sox11 occurred before the divergence of grass carp and zebrafish, which support the "fish-specific whole-genome duplication" theory. An estimation for the origin of grass carp based on the molecular clock using Sox1, Sox3 and Sox11 genes as markers indicates that grass carp (subfamily Leuciscinae) and zebrafish (subfamily Danioninae) diverged approximately 60 million years ago. The potential uses of Sox genes as markers in revealing the evolutionary history of grass carp are discussed.

Three novel bis-cationic asphalt emulsifiers were synthesized by two steps reaction of N-tallow-1,3-diaminopropane, methyl acrylate, sodium hydroxide and chloroacetic acid. The structure of the product was confirmed by FTIR, 1H NMR and elemental analysis. The emulsifier exhibits satisfactory emulsification. The prepared bituminous emulsion showed higher storage stability. The emulsifier belongs to medium-set and slow-set asphalt emulsifier. It can be designed to perform in a wide variety of applications including tack coat, fog seal, chip seal and slurry seal in asphalt pavement construction.

In this article a motion mechanism angle self direction-adjusting controlling system is designed. The main function of this system is to achieve the angle following control with the variation of inflow direction. This article describes the construction and working principle of the angle self direction-adjusting system, aiming to the controlling target the self-adapting fuzzy controller is designed, the controller is then simulated and analyzed after adding square wave signals. It is validated that the self-adapting fuzzy PID controller has a good dynamic, static and robust characteristics.

Aiming at the problem of lack of security equipment for airborne reconnaissance camera and universal difference between internal and external field and model, the design scheme of comprehensive universal system based on PC-104 bus architecture and ARM wireless test module is proposed is proposed using the ATE design. The scheme uses the "embedded" technology to design the system, which meets the requirements of the system. By using the technique of classified switching, the hardware resources are reasonably extended, and the general protection of the various types of aerial reconnaissance cameras is realized. Using the concept of “wireless test”, the test interface is extended to realize the comprehensive protection of the aerial reconnaissance camera and the field. The application proves that the security system works stably, has good generality, practicability, and has broad application prospect.

In order to improve the drawbacks of over-fitting and easily get stuck into local extremes of BACK propagation Neural Network, a new method of combination of wavelet transform and PSO-SVM (Particle Swarm Optimization- Support Vector Machine) power load forecasting model is proposed. By employing wave-let transform, the authors decompose the time sequences of power load into high-frequency and low-frequency parts, namely the low-frequency part forecast with this model and the high-frequency part forecast with weighted average method. With PSO, which is a heuristic bionic optimization algorithm, the authors figure out the prefer-able parameters of SVM, and the model proposed in this paper is tested to be more accurately to forecast the 24h power load than BP model.

As a new method to understand mathematics, visualization offers a new way of understanding mathematical principles and phenomena via image thinking and geometric explanation. It aims to deepen the understanding of the nature of concepts or phenomena and enhance the cognitive ability of learners. This paper collates and summarizes the application of this visual method in the understanding of mathematics. It also makes a literature review of the existing research, especially with a visual demonstration of Euler’s formula, introduces the application of this method in solving relevant mathematical problems, and points out the differences and similarities between the visualization method and the numerical-graphic combination method, as well as matters needing attention for its application.

Field monitoring of water quality during the autumn flood season in the middle and lower reaches of the Yellow River in 2021 was carried out. During this period, a host of methods, including the single-factor evaluation method, index evaluation method, and fuzzy mathematics method, were utilized to evaluate the water quality status. The relevant findings indicate that the water quality of the mainstream and tributaries in the middle and lower reaches of the Yellow River in the autumn flood season is excellent, which meets the water function zoning and water quality goals. In particular, the single-factor evaluation method emphasizes the use of the single index with the most serious pollution to represent the comprehensive water quality category, whereas the fuzzy mathematics method uses the multi-factor contribution rate to calculate the membership degree of water quality. Therefore, it is superior to the single-factor evaluation method in determining the water quality of the water functional zones within the evaluation scope. Meanwhile, the Nemerow index of the water quality of the tributaries of Yiluo River and Qinhe River at the section entering the Yellow River is lower than that of the mainstream, indicating that the water quality of tributaries is better than that of the mainstream during the monitoring period. Overall, the results of this research are conducive to the objective evaluation of the water quality of the Yellow River during the autumn flood season, thus providing more scientific technical support for the ecological conservation and restoration of the Yellow River basin.

The paper deals with the problems of balancing the United Energy System of Ukraine caused by high renewable energy penetration and the impact of the COVID-19 pandemic on the energy sector. The paper analyses the trends in renewable energy development, the dynamics and structure of electricity consumption and export in pre-epidemic and epidemic periods and identifies the main challenges to operational security of the United Energy System of Ukraine. The methodical approach to improve the methodology for estimation of country’s energy security level by considering the index of developing capacities for balancing the United Energy System of Ukraine is suggested. In addition, proposals have been made to reduce threats to the stable work of the United Energy System of Ukraine by putting into operation of energy storage capacities, promoting the development of мaneuvering renewable energy capacities, and implementation of other appropriate measures in this field.

The existing whip tail drive size parameter is obtained in the prototype a number of orthogonal experiments to obtain a value. In this paper, a new method is proposed. According to the resistance theory, a propulsive force calculation model is established, and then the local optimal solution is obtained through the combination of finite element method and genetic algorithm. The calculation is small and the thinking is clear. The obtained parameters are of reference to the prototype experiment.