Table of contents

Due to recent pandemic, the 2020 International Conference on New Energy and Sustainable Development (NESD2020) which was planned to be held in Changchun, China, was held virtually online during August 21-23, 2020. The decision to hold the virtual conference was made in compliance with many restrictions and regulations that were imposed by countries around the globe. Such restrictions were made to minimize the risk of people contracting or spreading the COVID-19 through physical contact. There were 60 individuals who attended this on-line conference, represented many countries including India, Pakistan, Australia, Brazil, South Africa, Ireland and China.

With the limitation of conventional energy sources and the increasingly prominent environmental problems, new energy sources with environmental protection and renewable qualities are gaining more and more attention from various countries. The research of new energy science and the development of industry are effective supplementary means of the entire energy supply system, and also the ultimate energy choice to meet the needs of sustainable development of human society. Under such condition, the organizer, AEIC as a link in the field of scientific research, will gather experts and scholars and engineering technicians in the fields of new energy science and engineering, sustainable development and environmental engineering around the world under the same roof. Jointly promote research progress in this field.

During the conference, the conference model was divided into three sessions, including oral presentations, keynote speeches, and online Q&A discussion. In the first part, some scholars, whose submissions were selected as the excellent papers, were given about 5-10 minutes to perform their oral presentations one by one. Then in the second part, keynote speakers were each allocated 30-45 minutes to hold their speeches. In the second part, we invited four professors as our keynote speakers. Assoc. Prof. Dr. Md. Akhtaruzzaman, from The National University of Malaysia, performed a speech on The Advancement of Inorganic Hole Transport Materials Towards Emerging Third Generation Thin Flim Solar cells. And then we had Prof. Michael Negnevitsky from University of Tasmania, Australia. He talked about High Renewable Energy Penetration and Power System Security: New Challenges and Opportunities. Prof. Jinghong Zhou, Changchun Institute of Technology, China, presented an insightful speech on Research progress and development trend of liquefied air energy storage technology. Lastly, we were glad to invite Assoc. Prof. Cangsu Xu, Zhejiang University, China as our finale keynote speakers. He shared a speech on Investigating the explosion of ethyl acetate in the presence of hydrogen. Their insightful speeches had triggered heated discussion in the third session of the conference. Every participant praised this conference for disseminating useful and insightful knowledge.

List of Committee member, Conference Chairman, Conference Procedure Committees, Technical Program Committees are available in this pdf.

All papers published in this volume of IOP Conference Series: Earth and Environmental Science have been peer reviewed through processes administered by the Editors. Reviews were conducted by expert referees to the professional and scientific standards expected of a proceedings journal published by IOP Publishing.

• Type of peer review: Double-blind

• Conference submission management system: AI Scholar Submission System

• Number of submissions received: 171

• Number of submissions sent for review: 158

• Number of submissions accepted: 99

• Acceptance Rate (Number of Submissions Accepted / Number of Submissions Received X 100): 57.9%

• Average number of reviews per paper: 2

• Total number of reviewers involved: 80

• Any additional info on review process:

Step 1. Each of the selected papers should be reviewed by two or three experts who are professional in the related area. A report of the reviewing result will come out by each expert.

Step 2. After collecting the reviewing reports from the experts, one of the editors will review the reports and decide whether the reports are approved.

Step 3. After that, the editors inform the authors of the reviewing results along with the three reviewing reports.

Step 4. Authors are required to revise their paper according to the requirements, then hand in the revised version to the editors. The editors send the revised version to reviewers and will decide whether the paper is approved to be published according to the reviewers' final reports. And at last the editors inform the decision with every details of the publication requirements if the paper is accepted.

• Contact person for queries:

Peijiang Zhou

Wuhan University

pjzhou@whu.edu.cn

At present, coal is the most important resource for utilization and development in China, but the environmental pollution caused by coal is serious. It is urgent to improve the development of clean energy. China is gradually promoting wind energy, the development and utilization of wind energy is difficult. The difficulty of storing wind energy and its instability limit the country's spread. Wind energy can only be developed better by solving the current problems. The research on the development and utilization of wind energy also becomes the key to solve the problem.

With the development of its economy and society in recent years, China's demand for energy is increasing. Traditional energy such as coal and petroleum can no longer meet the needs of China's economic development, because it is very easy to cause environmental pollution in the process of traditional energy reuse. In recent years, China has begun to explore, develop and utilize marine natural gas hydrates, which can achieve better energy effects in use and reduce environmental pollution. However, there are great difficulties in the exploration and development of marine natural gas hydrates and safety issues in the process of drilling the formation. In the process of research, based on the extensive research on the safety of marine gas hydrate drilling at home and abroad, this paper discusses and summarizes the safety problems encountered in Dacheng drilling, and organizes the research on the drilling safety issues of marine gas hydrate formation, providing reference for future research.

In the course of land project development, the environmental factors are often neglected in the assessment, but the damage of the environment usually leads to a much higher cost compared with its benefit. Therefore, a comprehensive evaluation model is expected to be built as our goal. First, we use the Logistic Regression Analysis to estimate the environmental cost. To simplify the modeling process, we select polluted river, poor air quality, poorly treated wastewater, climate changes to build the Nonlinear Fitting Model Based on Fourier Transform to calculate the cost of environmental degradation. Then use the model we built to analyze the cost-benefit of small community projects and large-scale national projects. Finally, taking the time factor into consideration, the long-term cost-benefit of land development projects is forecasted by using the neural network algorithm. Thus, a comprehensive valuation can be obtained as a reference for land project investors.

Reverse logistics optimization design for recyclable municipal solid waste is a social and economic problem. This paper mainly studies the location problem of reverse logistics network transfer station, which involves how to select the most effective location from the set of points to be selected. In this paper, an improved P median location selection model is proposed on the premise of minimizing the impact on residents, and greedy extraction heuristic algorithm is adopted to solve the model. Finally, the effectiveness of the model in the construction of MSW reverse logistics site selection is illustrated through an example analysis, and theoretical reference is provided for the actual site selection problem.

This paper uses the data of labor force, capital, all kinds of energy input, industrial pollutant emissions and output value of industries in 30 provinces and autonomous regions of China from 2011 to 2015, and uses big data and data envelopment analysis to calculate the industrial green efficiency of provinces and cities in China. At the same time, in order to explore the relationship between industrial agglomeration and industrial green efficiency, the panel regression model is used to conduct quantitative analysis. The results show that: whether from the national level or the eastern, central and western regions, industrial agglomeration can significantly promote the improvement of industrial green efficiency. Environmental regulation, industrial enterprise scale and other control variables can also significantly promote the improvement of industrial green efficiency in some areas, but not in some areas.

With the rapid development of urbanization, urban domestic waste is also increasing, if the garbage cannot be effectively classified, there will be a dilemma of garbage siege. In recent years, artificial intelligence technology has been applied in the field of garbage classification, which provides a convenient means for garbage classification. However, technological innovation can only alleviate the accumulated total amount of garbage, and finding the source of garbage generation is the key to solve the problem. Therefore, based on the theory of planned behavior, A-B-C theory and interpersonal behavior theory, from the policy level, the social level and the individual level, this paper puts forward some suggestions, it is composed of government, society, individual and other organizations, and puts forward the corresponding research hypotheses. Through interviewing and questionnaire survey in Guangzhou, the sample data are collected, and then regression analysis and structural equation model analysis are used to obtain the influence degree value of residents' attitude towards garbage classification, subjective norms, perceived behavior control, situational factors, and government legal regulation on residents' living garbage classification willingness. The results show that residents' attitude towards domestic waste classification is significant and the government's legal control factors are the key factors affecting the residents' willingness of garbage classification.

According to the requirements of modern enterprises for the classifying and managing system of product information, the structure of the flexible classifying and managing system based on internal and external codes is putted forward, the function and effect of every part are particularized, which was applied in the implementation of the PDM of turbine blade. It is shown from the application that classifying and managing system can promote the development of information in the enterprise.

DC microgrid has outstanding advantages in accepting new energy generation system and DC load, etc. This paper takes theislandedDC microgrid as the research object, and proposes a multi-time scale optimization scheduling scheme for theislandedDC microgrid. On the basis of satisfying the power balance of the DC bus and considering the factors of economy and environmental protection, this scheme realizes the optimized operation of the DC micro-grid under the isolated island mode. The optimization scheme consists of two stages: day-ahead scheduling and intraday scheduling. According to the short-term forecast data in advance, the day-ahead dispatching takes economic and environmental protection as the target todispatch controllable unit. In this paper, intraday scheduling maintains the power of the battery energy storage and interruptible loads determined by day-ahead scheduling. Taking ultra-short-term prediction data as the premise, intraday scheduling takes the minimum deviation between the output power of controllable power supply and the corresponding value of day-ahead scheduling as the target to formulate scheduling scheme. Finally, an example is given to verify the feasibility of the optimized scheduling scheme by simulating the proposed program on MATLAB.

To engage robots in live-line working and reduce the cost of electric power companies, this study proposes a binocular vision-based pose estimation method that can automatically identify the target's pose, guide the robotic arms to grasp the tools and fulfill live-line working tasks. First, this method matches and calculates the deep information of images via the binocular camera, and converts the images into the cloud of points; then, the advanced image segmentation technology is used to recognize the tools, and 3D modelling is conducted for the objects to accurately match the target image and the real target; the iterative closest point (ICP) method is used to solve the spatial pose of the target corresponding to the robot and thus guide the robots in tasks. Meanwhile, experiments are conducted to simulate the actual work process, and the result shows that the proposed method can accurately estimate the pose of targets and has good robustness and application value.

Based on the social and economic development, environmental protection needs, industrial policies and other smart energy systems have brought a new round of great changes compared with the traditional energy structure. Now the development of information technology provides a strong technical support for the transformation and upgrading of traditional energy to smart energy. This paper combines cloud computing, big data, artificial intelligence, blockchain and other emerging technologies to enable the traditional energy system, a smart energy system architecture based on cloud computing platform is proposed, which connects the bottom layer to the top layer of the energy system, and realizes the comprehensive integration of physical energy flow, information flow and value flow of smart energy.

Coal water slurry boiler has attracted great attention in the field of urban heat system because of its efficient and clean coal combustion. The coal water slurry contains 35% moisture, which makes the waste heat recovery potential of flue gas greater. After the combustion of coal water slurry, the 100°Cunsaturated flue gas becomes 50°C saturated wet flue gas after Wet Desulfurization Process. The Direct Contact Thermal Storage System and Heat Pump technology are used to realize the deep recovery of low-temperature flue gas. The technology has been successfully applied in the 6×70MW coal water slurry boiler of La Shan Heat Source Company. After 120 days of operation, 393000 GJ of flue gas waste heat is recovered, about 23000 tons of coal water slurry is replaced, and 84000 tons of flue gas condensate is recovered. It has good economic and social utility. It is an effective way to recover and utilize waste heat from flue gas of coal-fired boiler, and has a broad application prospect.

Solid oxide fuel cell (SOFC) is an efficient chemical fuel cell, which has been widely used in different fields. The successful application of this technology is of great significance to alleviate the energy crisis, meet the demand of the quantity and quality of electricity, and protect the ecological environment. SOFC has been utilized with gas turbine (GT), homogeneous charge compression ignition (HCCI) and small-scale power generation. This article introduces the characteristics, working principle and engineering application of solid oxide fuel cells in more detail.

Based on the model of "economic benefit-social benefit-ecological benefit", the evaluation index system of land use benefit was constructed, revealing the dynamic changes of the spatial and temporal pattern of land use benefit in Gansu Province. Combining the coupling coordination degree model, it analyzes the coupling coordination degree of economic, social and ecological benefits, and quantitatively analyzes its main limiting factors. The results show that: (1) The comprehensive benefits of land use in Gansu Province from 2000 to 2017 showed an upward trend. The spatial pattern of "high in the north and low in the south" was obvious, and a "dual core" structure with Lanzhou and Jiayuguan as the main cities was formed.(2) From the perspective of sub-systems, economic benefits show a trend of "rising first and then falling", and the spatial pattern is still "high in the north and low in the south"; the social benefits basically show an upward trend. The northwest is characterized by "first decline and then rise", and the southeast is characterized by "continuous rise". The spatial pattern is "high in the middle, followed by the northwest, and lower in the southeast". The ecological benefits are mainly present the trend of "rising first and then falling" markedly changed the spatial pattern.(3) From the perspective of the coupling coordination relationship, all cities in Gansu Province are in a state of imbalance, mainly with moderate imbalance, and the coupling coordination needs to be improved.

How to evaluate the ecological port and navigation project? What is the principle of evaluation? What are the criteria for evaluation? This paper discusses the evaluation principle and standard of ecological port and navigation engineering, and puts forward the evaluation principle of ecological port and navigation engineering. Then with the standard, the construction of ecological port and navigation project has certain guiding significance.

The development of a novel anode material with excellent cycle performance is of great significance to the promotion of the sodium ion battery. Adopting the renewable material BC as raw material, Nitrogen-doped Nb₂O₅-three-dimensional porous carbon fiber network composite (Nb₂O₅@N-CNF) is prepared by a low-cost approach in the paper. The in-situ growth of Nb₂O₅ nano-particles on the carbon fiber surface inhibits the agglomeration of particles. The porous structure of carbon fiber promotes ionic transfer. Meanwhile, the structure of pyridine nitrogen, which is formed by the doping of N atoms, further enhances sodium storage. After 1000 times of cycle under the current density of 2 A g⁻¹, the capacity of the Nb₂O₅@N-CNF electrode is 79 mAh g⁻¹, its capacity retention increasing significantly, with great application prospect.

Power quality monitoring system is an important means to find and evaluate power quality problems in time. A service-oriented browser / server (B / S) mode active power quality real-time monitoring system is designed and implemented, which provides the real-time monitoring function of power quality in the process of active power distribution network absorbing distributed power generation layer by layer, and focuses on observing the impact of the change of power flow direction on the level of power quality. Based on IEC 61850 standard, the system establishes the power quality information model, and uploads the real-time monitoring data of power quality on site to the master station for analysis and storage in the real-time database through MMS. The client communicates with the server through windows communication base (WCF) service to obtain real-time monitoring data, and realizes the global real-time monitoring function of power quality of active distribution network combined with the main wiring diagram, so as to achieve the integrated display effect of data graph.

In many countries, pumped storage power stations have gradually become management tools for the power system and are used to meet peak-shaving, valley filling and emergency reserve purpose. In addition, pumped storage power stations can be taken advantage of the unique valley filling function to facilitate the development of wind power, such as in Germany, one of the main approaches to digesting and saving wind power is to maintain a high share of pumped storage power generating capacity. Main factors affecting the scale and share of pumped storage power generating capacity include level of economic development, regional load characteristics, power mix and the peak-shaving capacity of interconnected systems. The capacity of pumped storage power stations is also affected by construction conditions, cost and the economics of other peak-shaving approaches of the power system. In China, the construction of pumped storage power stations is entering a fast-growth period. The government should incorporate the construction of pumped storage power stations into its long and medium-term power development plans and regard pumped storage power stations as part of regional power system. In addition, all of the functions offered by pumped storage power stations should be compensated by ancillary services supporting schemes.

In Granite acoustic emission tests were performed during three different cyclic loading and unloading processes. The relationship between the acoustic emission frequency distribution pattern and the loading and unloading mode of granite during the cyclic loading and unloading process was discussed. The distribution pattern of the peak frequency with the stress evolution is analyzed qualitatively and quantitatively. Studies have shown that: in the first cycle of loading and unloading at each stage of the three cyclic loading and unloading processes, the acoustic emission ringing count and peak frequency are significantly increased, which has a significant Kaiser effect. It proves that the Kaiser effect essentially remembers the extent of the damage inside the rock previously. In the process of loading and unloading in the fourth stage cycle, the AE ring count showed a "U"-shaped change law, showing a significant Felicity effect. Comparing the three different cyclic loading and unloading modes, with the increase of the lower limit stress, the stress amplitude decreases, and the AE ringing count corresponding to the lower limit stress value of the unloading gradually decreases, and the peak frequency distribution shows more dense or concentrated characteristics. At the beginning of the third stage cycle, the proportion of high frequency band (140∼162kHz) gradually decreased, and the proportion of lower frequency band (11-18kHz) gradually increased. With the increase of the lower limit of cyclic loading and unloading, the lower frequency band (11-18kHz) in the fourth-stage cyclic loading and unloading process takes up a higher proportion, even as high as 95%. It indicates that the rock samples at this stage mainly undergo large-scale failure, and the rock samples are in a critical failure state. These provide the basis for exploring the evolution mechanism of rock mechanical behavior and the prediction method of instability and damage.

Due to the complicated geological environment and karst hydrogeological conditions, water-inrush accidents often occur in the construction of tunnels in southwestern China. At present, there are many methods to predict tunnel water inflow, including analytic method and conventional hydrodynamic research method. There is a big discrepancy between calculated water inflow value and actual situation. Our research focused on the layered aquifer medium characteristics of water-bearing structure and movement characteristics. On the basis of existing tunnel gushing water inrush characteristics, the crossing relationships between tunnel and layered aquifer structure are divided into three categories, (I) tunnel longitudinal through layered aquifer structure, (II) tunnel through layered aquifer structure, and (III) tunnel obliquely crossing the layered aquifer structure. The revised formula of tunnel water inflow theory and experience in this study is inferred from steady-flow formula considering the boundary conditions. Inhomogeneous layered aquifer structure is considered as homogeneous structure, calculated by theory and experience formula. Next to the heterogeneity on one side of heterogeneity interface, the permeability coefficient of different strata can be fitted for a unified Kv; when crossing the layered water-bearing structure laterally, it is still calculated according to the original formula. When oblique crossing a layered water-bearing structure, the total flow rate is decomposed into two directions: transverse crossing and longitudinal crossing. The flow rates in the two directions are calculated respectively, and then superposed into the flow rates in oblique crossing.

With a large number of distributed energy and nonlinear loads such as photovoltaic and wind power are connected to the power grid, while improving the energy structure of the grid, it also greatly increases the harmonic content in the power grid, resulting in the decline of power supply quality and stability. In this paper, based on the analysis of the working principle of photovoltaic power generation system and the characteristics of the filter connected to the power grid, taking the inverter composed of high-frequency power electronic devices as an example, the principle of high-order harmonic generation is analyzed. According to this, a T-type filter is designed to suppress harmonics. The relationship between thd and filter parameters is studied, and the optimization method of T-type filter parameters is proposed Law.

Aiming at the echelon utilization of retired lithium-ion battery, an internal resistance detection system based on pulse discharging was designed. Taking STM32F103ZGT6 as the MCU of the lower computer, the collection circuits of voltage and current are designed, and the internal resistance of the battery is estimated by the collected information. The upper computer operation software is compiled, and the test results are stored in the database, which is convenient for management and query.

Based on the SOFC zero-dimensional model, a SOFC turbine combined cycle simulation platform is established. For the SOFC/GT combined cycle system configuration scheme with the preheater placed in front of the turbine, the influence of cycle parameters on system performance is analyzed. The current density-power characteristic curves at different outlet pressures, the fuel flow-efficiency characteristic curve and the turbine inlet temperature curve at different fuel utilization rates were calculated and analyzed separately when different low-temperature and intermediate-temperature combined cycle system configurations were used. The results show that the low-temperature SOFC/GT cycle maintains high-efficiency design conditions with a fuel utilization rate of 0.8-0.85, and the highest efficiency is about 52%. The design working pressure of the medium temperature SOFC/GT cycle is suggested to be 0.4MPa-0.5MPa, and the system efficiency will be higher than 50% when the compression ratio is at 0.8-0.85, and the maximum efficiency is about 64%.

Pumped-storage power plant(PSPP) is a special form of power supply. It is expected that the installed capacity of PSPP in China will reach 90GW by 2025. This paper summarizes the development of PSPP in China, and analysis the influencing factors of the configuration of PSPP, introduces the typical operation mode of PSPP and the existing problems in its development, and puts forward relevant policy suggestions for the development of PSPP.

Nowadays, Longitudinal gravity flow deposits, as a kind of important deep-water reservoirs, can form a certain scale of lithologic oil and gas reservoirs, which is of fundamental significance in the exploration of oil in Saihantala Depression. The evolution and sedimentary characteristics of the longitudinal gravity flow in the east subsag of Saihantala Depression are analyzed based on the core date, well logging, seismic data, regional geological data, and the method of seismic sedimentology. The sedimentary model of the longitudinal gravity flow and the exploration potential of the lithologic reservoir of longitudinal gravity flow are also discussed. The reservoir is mainly composed of medium-fine sandstone with developed secondary pores. The geological conditions for the formation of axial gravity flow are sufficient provenance, the development of slope breaks and the negative axial topography. The updip direction of the longitudinal gravity in the area has a short extension of the sand body, and the downdip direction has thick massive fine sandstones, which opens up pathways for lithologic reservoir exploration.

The green technology spillover (GTS) is conducive to follower's innovation opportunities but harmful to pioneer's innovation advantages. Based on the knowledge production function and the panel data of cities in China, this paper discusses the effects of GTS on the relationship between the low carbon regulation (LCR) and the green technology innovation (GTI) by using the Spatial Durbin Model. We found that LCR makes a decrease-increase effect of the pioneer's GTI different from an increase-decrease effect of the follower's GTI.

In this paper, according to the design requirements of the battery cabin and the structure of the frame, the finite element model is established. The static analysis and constrained modal analysis are carried out for the battery cabin under two extreme conditions of bumpy sharp turn and bumpy emergency braking, and the first six modal frequencies and modes are obtained. The optimized battery cabin achieves the goal of 2% lightweight optimization design, and other performances are satisfied. After the topography optimization, the endurance and rigidity of the battery cabin are improved to varying degrees. The elastic limit of the material is much higher than the maximum stress. The weight of the battery cabin is reduced by 2.5% through topology design.

The accurate positioning of the voltage sag disturbance source relative to the monitoring point helps to clarify the responsibilities of both parties. This paper proposes a brand-new single-frequency cross S-transform perturbation power positioning method for locating voltage sag disturbance sources. First, the voltage and current signals collected at the monitoring point are transformed into a single fundamental frequency S to obtain a complex vector of the fundamental frequency of the voltage and current; then, the complex vector of the voltage and current fundamental frequency is subjected to a single fundamental frequency cross S transformation. The module extracts the instantaneous apparent power, and then obtains the instantaneous apparent disturbance power; finally, the disturbance power criterion is used to locate the source of the voltage sag disturbance. Through analyzing and judging the monitoring point of the problem caused by short circuit fault, the result proves the accuracy and effectiveness of the proposed method.

This paper analyzes the feasibility of implementing open source innovation mechanism and the path of realizing open source innovation in new energy vehicle enterprises. Based on the main features of open source innovation and characteristics of electric vehicle products, combining the product type of electric vehicle and the process of product innovation, we applies the principle of technological innovation management to design the operation mechanism and conceptual model of different authorization protocols with the elements of innovation object, operation mechanism and innovation performance.

In the coal stopping process, it often happens that the mining face crossing empty roadway often causes increase of the advanced support pressure, and leads to problems such as roof fall and rib spalling, in response to which, taking a recovery mining face in Xipang Mine as the engineering background, and using software FLAC^3D to establish the numerical analysis model of the mining face crossing empty roadway, the study on the influence of incline adjustment of the mining face crossing gob on the surrounding rock near the empty roadway. The result shows that with the decrease of the width of coal pillar between mining face and empty roadway, the vertical stress appears three shapes in turn: "saddle shape", "platform shape" and "solitary peak shape"; stress concentration occurs at the intersection of two roadways, and the stress concentration in acute angle area is more obvious. Adjusting the inclination of the mining face and increasing the angle between the mining face and the empty roadway are beneficial to reduce the stress concentration phenomenon of the coal pillar in the triangle area, and the maximum supporting stress is reduced from 25.3 MPa to 23.5 MPa, which is more conducive to the safe passage of the mining face through the empty roadway.

In the face of voltage sag which causes power quality problems, combined with the common short circuit fault types in power system, how to locate disturbance source quickly and accurately is an important problem in low frequency oscillation monitoring and control. The mechanism of the disturbance source affecting the unit in the network is analyzed. A low frequency oscillation source location method based on oscillation phase difference is proposed. Firstly, the electrical data of the dominant oscillation mode are extracted by empirical mode decomposition, then the oscillatory phase with physical meaning is calculated by Hilbert transform. According to the network information criterion, the location of the disturbance source can be traced, according to the power plant. The ground information criterion can check the specific disturbance source unit. The principle of the method is clear, only one electrical quantity is needed to participate in the calculation.

With the wide application of new energy power generation and pumping unit frequency converter driving, the phenomenon of multiple converters installed has been formed in oilfield power grid. The interaction characteristics of multiple converters are vital to the stability and safety for oilfield production. This article introduces firstlythe typical topology of multiple converters based on generation and consumption in oilfield power grid. The different combination forms of converters and the influence of DC bus control performance in the DC side are researched. Then interaction characteristics are analyzed based on the peak value of transient current and voltage, and the protection setting value. In order to improve the stability and safety of the system, the layout principle of the converters is proposed. Moreover, the ultimate capacity output principle is proposed to reduce the voltage and current stress. Finally, the correctness and effectiveness of the above are demonstrated through simulation and analyses.

A new method of field dynamic balancing for double rotor turbo-generator set is studied in this paper. According to the vibration mode characteristics of the shaft system of this type of unit, this method creatively uses the balancing slot of the fan at the rear end of the generator rotor as the only balancing plane, and uses a specific calculation method to eliminate the vibration of the shaft system in the horizontal direction caused by the deviation of the coupling and mass imbalance by applying the counterweight only once.

In these years, with the increasingly serious human damage to the water environment, the world is seeing a more gloom prospect for water pollution control, and non-point-source pollution accounts for the major cause of water pollution. Currently, establishing non-point-source pollution load models to simulate the formation, transfer and load capacity of the non-point sources has become a major solution to control and treatment of non-point source pollution. The present study selected two classic basin-scale non-point source pollution distribution models — SWAT and HSPF, introduced their respective structures and application, and compared comparative analysis. The existing challenges and development trend of non-point source pollution models in China were also explored.

This paper analyzed the input and output data of wind farm based on deep neural network, developed intelligent model, and realized the predictive modeling of important parameter variables and control of wind turbine. By establishing the Deep Extreme Learning Machine(DELM), the higher-order nonlinear model is simplified. In this structure, unsupervised hierarchical ELM is conducted for feature extraction, and the features of the lower layer are transferred to the higher layer through layer by layer coding to form a relatively complete feature representation. Finally, the Extreme Learning Machine (ELM) is used to complete the mapping of feature representation to target output to minimize the loss of information in the transmission process. The target output is used as reference data for Pitch control of wind turbine, which is proposed by using a radial basis function (REF) neutral network. Simulation results from GH-Bladed show that proposed control algorithm can mitigate the loads effectively. The algorithm provides a practical reference for the design of wind turbine controller.

Short-term electric power demand forecasting is the most basic and important application of smart grid. With the rapid development of renewable energy and clean energy in recent years, power demand forecasting gains special attention again. It has a great impact on the planning of power generation units and the purchase and sale of power market. Furthermore, itis also conducive to the realization of demand response and resource allocation efficiency and reliability, thus contributing to the Photovoltaic power generation system as well. Although generous methods have been proposed, it remains to be an open challenge owing to its limited precision. In this paper, a hybrid method of Seasonal Auto-Regressive Integrated Moving Average (SARIMA) and Support Vector Regression (SVR) is proposed for hourly forecasting, which overcomes the difficulty of generalization of a single model. The core thought of this model is using SARIMA to fit the linear part of the series and correcting the deviation by SVR. We tested the accuracy of this method on a public data set, and the result shows that it performs much better than the single SARIMA model on the fitting effect. Also, we compared our model with the recent three works, and it demonstrates a decrease of 18.102%,10.534% and 4.757% in forecasting error respectively. To our surprise, when we usedthe previous four hours of data to predict the current data by the single SVR, we got the best performance of all models. In the end, we analyzed the possible causes for this result.

Prelithiation technology can improve the service life of batteries, but whether it will affect the safety of batteries has not been studied. In this paper, the temperature differences between LiFePO₄/C batteries with prelithiation technology and conventional LiFePO₄/C batteries in overcharge test are analysed, the shell deformation values of these two types of batteries are compared, and the influence of battery capacity retention rate on overcharge safety of batteries is discussed. The analysis shows that there is no obvious difference in overcharge safety between two types of batteries, and batteries with prelithiation technology are similar to conventional batteries in terms of shell deformation value, the highest temperature of shell and the temperature fluctuation of flue gas escaping from pressure relief valve.

Dual-permanent-magnet vernier motor incorporates the merits of high torque density and low cost, suitable for low-speed high-torque applications. Due to integral saturation and high current ripples in dual-permanent-magnet vernier motor control system, a model predictive current control strategy based on Anti-Windup PI controller is proposed. Adaptive adjustment variable structure is adopted in integral segment of the controller, which can quickly eliminate integral saturation in system. Mode predictive current control based on dual vector is adopted in current interior loop of the system, double arbitrary voltage vector can be selected to operate simultaneously in each control cycle that extends selection range of voltage vector and adjustment range of amplitude, which can realize more accurate current control. Meanwhile, considering system delay, current delay compensation is added to predictive control. The simulation results showed that proposed control strategy can effectively restrain integral saturation, reduce current ripples, thus improving dynamic and steady state performance of the control system.

The bulk cargo terminal conveying system has the problems of low equipment efficiency and high energy consumption during operating conditions such as no-load starting, ship loader shifting, and ship unloader clearing. In this paper, combined with the full frequency conversion control technology, the research on the frequency conversion control mode of the bulk cargo terminal and the energy saving effect test are carried out, and the optimized control method for the energy saving process is proposed. Under various common working conditions, the bulk cargo terminal can control the belt conveyor to run at low or zero speed according to the actual situation on the spot, so as to minimize energy consumption.

The dismantling of large-span steel roof is a complex evolutionary process involving redistribution of internal force. In order to ensure conformity of the structural internal forces to the design, safety and reliability during the demolition, it is necessary to make accurate simulation analysis of the dismantling process to determine a reasonable dismantling plan. With a review of the simulation methods adopted in the dismantling process of large-span steel structure and analysis of the relevant research results, this paper elaborates on advantages, disadvantages and adaptability of each method, which can serve as a basis for the study of roof dismantling.

When the microgrid operates in island mode, the droop control can be adopted to realize effective power distribution among distributed generations (DGs). Due to the different line impedancesof the various DGs, disproportional power distribution and circulating currents occur in conventional droop control, which make it difficult to maximize the efficiency of DGs and even may cause some DGs overloads. Therefore, an improved droop control strategy with an adjustable droop coefficient is proposed. The relationship between line impedance and reactive power is obtained by analysing conventional droop control. Then a new droop control algorithm is proposed. By introducing the output reactive power information of other DGs into the integral feedback link, the droop coefficient is modified to realize the accurate distribution of reactive power. The model is built on the Matlab/Simulink platform, and the effectiveness of the proposed control strategy is verified by comparing its reactive power distribution resultwith that of the conventional droop control.

In view of the operating conditions of the bulk cargo terminal, a bulk cargo terminal frequency conversion speed regulation control scheme and an intelligent full frequency conversion speed regulation algorithm are put forward, thestudy completes the intelligent speed regulation function of the belt conveyor according to the source material flow. This research solves the problems of low equipment efficiency and high unit energy consumption caused by uneven distribution of material flow and long-term no-load operation of belt conveyors under various operating conditions. Research on the optimization of intelligent speed regulation algorithms provides strong technical support for the construction of green ports and the completion of energy-saving and emission-reduction targets for the water transportation industry.

With the access of distributed generator, it changes the trend of the distribution network flow and voltage distribution. And the output power of the DG has the characteristics of randomness and interval, which can affect the control strategy of the transformer substation. In order to improve the influence of the distributed power on voltage, in this paper, based on the typical chain-shaped radiative distribution network, the influence of voltage distribution after the access of distributed generator is studied. On this basis, a coordinated control strategy based on wide-area information "bus voltage priority regulation, distributed power supply coordination regulation" is proposed, which takes full-line voltage reaching the standard as the optimization goal. Through the simulation of the improved IEEE 33-node distribution network, it is verified that the coordinated control strategy can effectively improve the power quality of the distribution network, and control the voltage deviation within the allowed range.

Massive accumulation of vanadium-titanium magnetite tailings (VTMT)—a kind of common industrial solid wastes—will pose enormous harms to both ecological environment and economic development. Based on the preparation of water-storage ceramic foam by taking full advantages of 50 wt% VTMT and 50 wt% waste glass, the effect of sintering temperature on the sample performance was further investigated through a test, and the foaming mechanism at high temperature was deeply probed. The results show that as the sintering temperature rises, the bulk density and compressive strength of the sample gradually decline, its water absorption per volume reaches the maximum value and the average pore diameter inside the sample is gradually increasing. The optimal sinter temperature is 1,040 °C, and the water absorption, bulk density and compressive strength of the sample are 56.5%, 0.26 g/cm³ and 0.68 MPa, respectively.

In the stable production stage CBM wells have the characteristics of high gas production and low water production. The use of continuous velocity tube technology for drainage can achieve better drainage results. Accurate and rapid prediction of the pressure drop of velocity pipe string production in a coalbed methane well has become the key to the operation and management of velocity pipe technology. This paper uses the nonlinear mapping and prediction capabilities of the BP neural network to build a three-layer BP neural network to construct a velocity pipe string production pressure drop prediction model. The model is based on gas production, water production, bottom hole pressure, pipe string diameter, and well depth. The five factors are input, and the pressure drop of the pipe string is the output, which can quickly and accurately realize the pressure drop analysis and calculation of the speed pipe drainage. The analysis shows that it is feasible to use the BP neural network to calculate and analyse the pressure drop of the velocity string of coalbed methane wells.

The research on the harmonic mechanism and features of new energy generation units is crucial for ensuring safe and stable operation of new energy generation. In this paper, a big data analysis method suitable for the operation data of new energy power plant is used to analyse the harmonics generated by PWM modulation and dead zone effect of switching devices and the interharmonics generated by DC side voltage fluctuation. The simulation analysis verifies the harmonic characteristics of new energy power converter, the model basis of new energy power generation operation evaluation and power grid connection certification.

Satellite remote sensing data with moderate-to high-resolution has been commonly used in deriving spatial coverage of PM_2.5 concentrations in urban areas. Previous studies focusing on city-scale PM_2.5 estimation mainly retrieved aerosol optical depth from moderate-to high-resolution remote sensing data. In this study, the spectral response experiment was carried out to explore the sensitivity of spectral wavelengths to PM_2.5 concentrations in Fuzhou, China. The results showed that the near-infrared reflectance was much more sensitive to PM_2.5 than other wavelengths. We also found that the difference vegetation index (DVI) presented higher correlation with PM_2.5 than other indexes. A linear mixed effects (LME) model was then developed to explain the variability of PM_2.5, and the results showed that the overall R² of LME model using DVI and meteorological parameters reached 0.80 with RMSE of 7.82 μg/m³. The results suggested that the proposed LME model using DVI from Landsat 8 OLI could be effectively used for predicting PM_2.5 in a city scale.

Downhole shear swirling flow vibration cementing tool has shear, rotational flow and vibration triple effects. It can improve cementing quality in various aspects. This paper developed discussion in the aspects of the tool to change cementing fluid performance by shear, to realize turbulent displacement and improve the wall shear stress by swirling flow, to change periodically relative position of clearance by casing eccentric revolution, to increase compression strength of cement by vibration and so on. It analyzed the mechanism of enhancing cementing quality of the downhole shear swirling flow vibration cementing tool in detail. It deepened the understanding of the tool. Then the research results help to promote the tool further application in oil and gas well cementing engineering field, and further increase the oil and gas well cementing quality.

In order to compare and study the performance of SOFC/SCO₂ cycle and SOFC/GT cycle, the efficiency of SOFC/GT cycle under the same working temperature and the middle temperature and low temperature SOFC/SCO₂ combined cycle system was compared and analyzed. The cycle parameters of the non-pressurized SOFC/SCO₂ system at the highest efficiency are retrieved by genetic algorithm. The research results show that the efficiency of the SOFC/SCO₂ combined cycle is about 5% lower than the efficiency of the SOFC/GT cycle under medium temperature conditions. Under low temperature conditions, the efficiency of the SOFC/SCO₂ combined cycle is about 4% higher than the efficiency of the SOFC/GT cycle in all operating conditions.

Accurate wind speed prediction plays an important role in the planning and development of wind power plant. Wind speed prediction can reduce the impact of wind power grid connection and improve the control of wind power systems. In this study, wind speed is considered as a geographical variable. We firstly used exploratory methods to examine the spatio-temporal dependence on wind field. The variogram was taken into account in analysing the spatial structure in the rectangular grid. Then the exponential model was adopted to fit the anisotropic feature of variogram. The de-trended data have been computed by using a geostatistical kriging estimator. The results were compared with the leave-one-out cross-validation (LOOCV) method. The accuracy of the proposed method was verified to obtain the best estimated results.

In the context of today's growing emphasis on environmental issues, the paper analyses 2018 pollutant data from eight sites in Taiyuan. The relationship between PM2.5 concentration and time (season, month, week) was analyzed by the R language, and the reason for PM2.5 concentration variation was inferred. Air Pressure, wind speed, precipitation, and vehicle restrictions all affect the concentration of pollutants.

Lithium metal batteries (LMBs) using lithium metal as the anode is a promising technical route for the next battery. lithium metal anode delivers the highest energy density. Therefore, it has been extensively studied by scientists. Unfortunately, Li-metal anode is incapable to practical applications due to the dendritic propagation during the repeated charging/discharging process leading to short-circuit and severe safety issues. we loaded the fast Li-ions conductor LLZTO ceramic particles on the polysulfone (PSU) fiber. The LLZTO/PSU composite fiber membrane networks inherited both lithiophilic properties and strong rigidity from LLZTO particles, which could suppress the local electric field and exert influence of adjusting the distribution and deposition behavior of Li-ions while the improved mechanical properties against lithium dendrites. Therefore, the lithium metal anode with modified surface of composite fiber can effectively inhibit the formation of lithium dendrites with a prolong life-span.

In the case of periodic load disturbance, the chaos oscillation phenomena may be caused by synchronous generator to threaten the safety operation of the network. In order to solve this problem, this paper presents the strategy on the control of linear feedback adaptive fuzzy siding mode. Under the action of the controller, the system output track the desired trajectory, and the fuzzy control rules are used to suppress the high frequency chattering in conventional sliding mode controller. The theoretical analysis and simulation results show that the designed controller can effectively control the power system oscillation, and it has certain robustness.

With the gradual integration of various forms of energy, the energy utilization rate has increased and it also brings great challenges to grid evaluation. Therefore, the use of scientific and reasonable comprehensive evaluation method can provide effective help for the development of power grid. In order to solve the problem that the traditional single evaluation method is used in the comprehensive evaluation of power grid, resulting in too strong subjective awareness and lack of evaluation of the objective original data itself and uneven weight distribution, this paper proposes that Nash equilibrium solution is introduced into BWM entropy weight as the goal of coordination and optimization. In the method, the comprehensive weight is calculated, and the distance between the selected scheme and the ideal scheme is sorted by TOPSIS. This method combines all the information of objective data to balance the subjective and objective weight. Through this method, 16 indicators of safety and benefit in 25 provinces in 2017 of State Grid Economic Research Institute are analyzed, and the feasibility of this method is verified.

In the actual operation of the power system, some generating units may have physical limitations. For a unit with prohibited operating zone, its operation zone [Pmin, Pmax] will be divided into several discrete sub feasible regions. In this paper, the influence of units with prohibited operating zone on the system is deeply studied, and the influence of units with prohibited operating zone on other units in the system, including the influence between units with prohibited operating zone, and the optimal solution state of economic dispatch problem for units with prohibited operating zone are further studied. Then the iterative algorithm for the above three problems is modified. At the same time, the economic law and physical essence of the economic dispatch problem for units with prohibited operating zone are explored. With high calculation efficiency, the algorithm proposed in this paper has its own engineering application value.

In view of how virtual power plants can effectively participate in power grid operation, a method of load curve clustering of virtual power plants based on principal component analysis reduction and aggregation level clustering and k-means clustering is proposed, and the application of clustering results is studied. Firstly, combined with the data obtained from the information physical network, the principal component analysis method is adopted to analyze the characteristics of different loads participating in the virtual power plant aggregation, so as to standardize the data and reduce the dimension. Then, the algorithm combining aggregation hierarchical clustering and k-means clustering is used to cluster all load output curves participating in the aggregation, to obtain load curve clusters of the same class and find out the clustering center. Finally, the clustering results are analyzed, and the corresponding evaluation system is established. Through comprehensive evaluation, appropriate load combinations are selected to participate in the virtual power plant aggregation.

The design of a thick wind turbine airfoil is a multi-constraint and multi-objective optimal problem. In order to make the thick airfoil with a blunt trailing-edge have better aerodynamic and structural performance simultaneously, a new method for thick airfoil optimal design based on an improved MOPSO algorithm was presented in this paper. To show the performance of the new design technique, the optimization is accomplished on the wind turbine airfoils with a 40% maximum relative thickness, and the Pareto-optimal set is obtained. The representative airfoils are picked, analyzed, and compared with a traditional wind turbine airfoil (DU00-W2-401) at Re=2×10⁶ for free and fixed transitions, the results show that the new airfoils have better performance than the DU00-W2-401.

As photovoltaic, wind power and other new energy sources are connected to the power grid on a large scale, the research on key technologies of microgrid needs to be further improved. Since most distributed generation and energy storage devices are mostly powered by direct current, DC distribution technology has got more and more attention. Aiming at the difference of energy efficiency between AC and DC microgrid, this paper proposes the analysis method of "the efficiency of source side with distributed generation", establishes a mathematical model of system loss of AC and DC microgrid with distributed generation and sets up a selection principle of distribution system mode through the intersection point of system loss rate, from the perspective of energy efficiency. The calculation results show that the loss rate of DC microgrid with distributed power source is lower than that of AC microgrid supposing the DC load ratio is 50%. The system loss rate curve confirms the necessity of DC distribution system technology research. With the continuous access of distributed generation and energy storage devices to microgrids, and the increasing improvement of DC load rate, the DC microgrid with distributed generation will have more advantages in the future.

During the operation of a steam turbine in a power plant, the no.3 bearing of the LP rotor suddenly vibrated strongly, which caused the protection action and the turbine tripped. During the maintenance it was found that serious rubbing occurred between the impeller of the LP rotor and diaphragm gland in the LP cylinder. Through inspection and analysis, the location and cause of the rubbing were found, and corresponding treatment was carried out. During the start-up process after maintenance, the vibration of no.1 bearing of HP/IP rotor increased to trip value. In order to eliminate the rubbing of HP/IP rotor, the appropriate warm-up speed was selected and the speed control method was adopted to make the unit start to the working speed and put into normal operation.

In horizontal Wells, non-uniform ground stress is the root cause of irregular borehole shape. The failure of caliper instrument in horizontal section leads to the failure of accurate evaluation of borehole shape, which makes it difficult to calculate the frictional resistance of tubing string in the later stage. This paper studies the borehole shape calculation model from the following two aspects: (1) in the aspect of diameter expansion caused by shaft wall collapse. By establishing coulomb-Mohr criterion in cylindrical coordinate system, the well wall collapse instability is judged, and the hole diameter expansion is evaluated by establishing the calculation model of the instability range. (2) Shrinkage caused by stress concentration. Firstly, the boundary position of formation deformation is determined. Secondly, the calculation model of borehole deformation is established by analyzing the stress characteristics of formation, which reflects the time effect of borehole deformation. Therefore, the establishment of borehole shape calculation model of horizontal well provides a basis for calculating the friction between the pipe string and the horizontal section.

Nowadays, the smoke prevention and exhaust system has not been effectively taken seriously, but smoke in fire disasters have become an important cause of death. In this paper, some problems still exist in smoke prevention and exhaust system will be concluded including design inspection and maintains. Meanwhile, a new method of calculating volumetric flow rate of smoke exhaust in high-rise building will be shown. The results show that the the existing prevention and exhaust systems in high-rise buildings have some defects and need to be upgraded. Outdoor wind in high-rise buildings is an important effect of fires. Some significant and easily ignored aspects of inspection and maintains will also be summarized.

The Es3 reservoir of Jin45 fault block has been developed for many years, and now it is faced with problems such as high water content, serious casing damage. In order to change the current development status of Jin45 fault block, the Es2 reservoir is put into development which located in the upper part of Es3 reservoir. The well pattern direction, well pattern form and well pattern density of Es2 reservoir are optimized by various methods in this study. On the basis of Es2 reservoir well pattern optimization study, the new well pattern of Es2 reservoir and the old well pattern of Es3 reservoir are comprehensively considered and compatibly adjusted. While the new well pattern is put into development, the injection-production system of the old well pattern is improved by using the new drilling wells, and the potential remaining oil is exploited, which lays a foundation for the efficient development of the old oilfield.

To understand the spatial-temporal characteristics of ozone in Taiyuan, the ozone concentration data of Taiyuan National Control Point in 2018 were analyzed. The results show that, in 2018, the data of ozone as the main pollutant in Taiyuan did not exceed the annual average standard. The monthly distribution of ozone was inverted "V" and the highest average concentration appeared in July. The diurnal variation of ozone didn't show an anti-weekend effect. In terms of spatial distribution, the difference between all the eight points was not obvious.

With the growing number of onboard ECUs, the load of classical CAN (Controller Area Network) is aggravated to produce transmission delay issue. A new protocol CAN-FD (Controller Area Network with Flexible Data-Rate) was presented by the BOSCH company to meet the high speed and real-time data exchange needs of the intelligent vehicles and ITS (Intelligent Transport System). For the vehicle electronics, the CAN-FD data network is still growing up. In this paper, the classical CAN and CAN-FD in protocol are compared through experiments. Results show that: (1) the terminal resistors have more effects on the CAN-FD than the CAN; (2) the bit rate of the CAN-FD can be ten times of that of the CAN; and (3) the data transmission efficiency of the CAN-FD network is affected by both the bit rate and the data length. Additionally, the physical network configuration takes decisive effect on the minimum frame interval of the CAN-FD frame.

Lithium-sulfur batteries have attracted attention when competing with the next-generation of rechargeable batteries due to their higher theoretical specific capacity, lower cost, and non-toxic and harmless feature. However, there are many obstacles towards the practical application of lithium-sulfur batteries such as low conductivity of the positive electrode and discharge products, the "shuttle effect" of polysulfides, and the unsafety of the lithium negative electrode. In this paper, Cr-MOF@MWCNT as a separator modification layer is introduced into lithium-sulfur batteries to solve the problem of "shuttle effect". The Cr-MOF in the coating layer can adsorb polysulfides, and the MWCNT tightly combined with Cr-MOF helps to build a good conductive network, so that the adsorbed polysulfides can be converted. As the initial specific capacity and cycle stability of lithium-sulfur batteries with the Cr-MOF@MWCNT separators have been improved, the initial specific capacity is as high as 1377 mAh g⁻¹ at a rate of 0.2 C, while the average capacity attenuation per cycle after 300 cycles is 0.14%, with 99.8% of coulombic efficiency.

The emerging industries are usually driven by innovations and represent the development directions of advanced economic. Particularly, this manuscript explores the innovation diffusion and S-Curve theoriesto study emerging industries which are characterized with rapid demand variations, where the new energy vehicle industry serves as an example. The S-Curve is deduced in detail as a theoretical foundation for the study of the rapid demand changes of emerging industries. Base on authority data of vehicle sales in past decades, the NPS and EV30@30 scenarios from IEA are analysed to reveal the worldwide trend of electric vehicle industry. And as the largest market of new energy vehicles in the world, Chinese electric vehicle industry exhibits obvious impetus of government policies on the market development, and foresees a significant penetration of electric vehicles into traditional transportation sector in near future.

According to the investigation data of Jiaozhou Bay in 1992, the vertical distribution, horizontal distribution and seasonal variation of Cd in the surface and bottom waters from the center of the bay to the south of the mouth of Jiaozhou Bay are studied, and the seasonal distribution, range of distribution and horizontal distribution trend are determined. The results show that in May, August and October, in the waters from southern mouth to the center of the bay, the Cd content of surface and bottom waters ranged from 0.12-1.19μg/L, in line with the national water quality standards for Class I and Class II seawater, which indicates that water quality was slightly polluted by the Cd content orwas not polluted. The surface levels of Cd vary seasonally from low to high: spring, summer, and fall, the same was true for Cd seasonal variation in bottom waters. In the surface and bottom waters of Jiaozhou Bay from the south of the bay mouth to the center of the bay, in May, August and October, when the Cd content in surface waters was relatively low, and the corresponding bottom layer was relatively low; when the Cd in surface waterswas relatively high, the corresponding bottom layer was relatively high; this shows that the loss of Cd content both from the surface and the bottom was relatively high. In May, August and October, in the waters from the southeast of the bay to the center of the bay, the horizontal distribution of Cd in the surface and the bottom waters have an opposite trend. From May to October, the seasonal variation of Cd content in surface waters in the southeast of the bay was mainly affected by the Cd content transported by main sea currents, while the bottom waters are mainly affected by river-transported Cd content. From May to October, in the central waters of Jiaozhou Bay, the seasonal changes of surface and bottom Cd content are not consistent withthat of Cd content transported by main sea currents. On the temporal scale, in the waters of Jiaozhou Bay from the south of the bay to the center of the bay, in May, August and October, the Cd content in the surface and bottom watersvariateswithin the same range, maintaining the consistency. On the spatial scale, in the waters from the southeast of the bay to the center of the bay, in May, August and October, according to the comparison between the Cd content transported by main sea currents and that transported by rivers, it can be proved that the horizontal distribution of Cd content in the surface waters was opposite to that of in the bottom waters.

This paper puts forward the concept of port and navigation engineering of the fifth generation. Starting from the concept of port, it points out that port has gone through the change from the first generation port to the fourth generation port, and now it has entered the stage of the fifth generation port. The main functions of the fifth generation port include the functions of the previous four generations, while it also focuses on the combination of port city and port town, and its main characteristics are efficiency, ecology and low carbon. Then it puts forward the concept of ecological port and navigation in narrow sense and broad sense. In the narrow sense, the ecological port and navigation refers to the ecological port of the fifth generation port above the third and fourth generation ports and the ecological channel centered on the ecological port. In the broad sense, ecological port and navigation refers to the port and navigation system that combines ecological port, ecological channel, ecological port city and ecological village. The fifth generation port and navigation engineering is the port and navigation engineering corresponding to the fifth generation port, ecology is its most important feature, which is the new promotion of port and navigation engineering concept.

In the future, travel revolutions such as shared travel will bring great changes to the structure of transportation, and the charging characteristics of electric vehicle will also be affected. This paper takes the new travel mode as the research background and models the driving and charging behavior of electric vehicle group. Then the multi-agent technology is used to build a large-scale electric vehicle group simulation model. This model fully considers the capacity constraints of traffic network and charging station, which can be used to simulate the actual behavior of electric vehicle group. Finally, the charging load curve of the electric vehicle group under the new travel mode is obtained based on simulation. The result shows that as the proportion of shared travel increases, the daily average charging load keeps increasing, and the charging load peak comes earlier and lasts longer.

With the continuous development of science and technology, there are many power quality problems which are different from those in the past. A large number of innovative electrical equipment will bring a lot of harmonics in the process of work, which will not only cause potential safety problems in the power system, but also cause serious harm and impact on the normal operation of all power dependent working equipment. In this paper, active power filter (APF) is studied for harmonic control of distribution network. A new APF current compound control method is proposed, which is based on Deadbeat and repeat plus LADRC in series. It improves the accuracy of harmonic compensation, enhances the anti-interference ability and dynamic performance, and achieves the purpose of precise control of current loop.

High pressure governing valve is modelled by elliptic equations, and verified through the comparison with the literature data. Then a 660MW ultra-supercritical steam turbine with throttle steam distribution mode is modelled to explore the efficiency of HP cylinder and the unit's economic under different loads with different operation strategies. Analysis shows that the valve opening is an important factor that impacts the heat rate and the valve in 30%-40% opening should be recommended for operation. According to the requirements of grid frequency adjustment, the proposed operation strategies can improve the units' economic performance and enhance the ability of deep peak regulation.

Along with fast economic growth, population increase and accelerated urbanization, the land use pattern of Xi'an is experiencing tectonic changes. Studying the land use change volume and spatial distribution in different regions in Xi'an will provide a basis for future studies on the urban spatial arrangement, land use management optimization and sustainable land use development. Based on GIS and RS technologies, this study explored the land use changes in Xi'an, analyzed the type, quantity, spatial arrangement and density of land use change, and introduced quantitative parameters including the dynamic level of land use, the transfer matrix, etc., for analysis. The results revealed that: 1) the major land use types in Xi'an were farmland, forest and built-up land; 2) in these 15 years, the area of grassland and built-up land increased, while the area of farmland decreased; 3) the dynamic level of comprehensive land use change increased, indicating intensive land use changes in Xi'an.

Creative enterprises are the backbone of the development of cultural and creative industries. This paper analyzes the current situation and crisis of creative enterprises in Jilin Province in the construction of cultural creativity and design service market in the era of big data, and puts forward some strategies to solve the crisis of enterprises so as to improve the core competitiveness of independent intellectual property rights of enterprises, to achieve the cultural and creative industry and other industrial integration and development, and accelerate the industrial transformation.

China has entered the era of informatization of big data on the Internet. The Internet has subtly influenced people's study, work and life, and even influenced the process of social development. At present, China is moving from a big Internet user country to a strong Internet technology country. The development of the Internet industry has been scaled up, and its application field is gradually becoming multi-dimensional. Today's animation industry, as a new format for the development of cultural and creative industries, is facing business opportunities and challenges. Traditional communication methods have been unable to meet the development needs of the market, and animation companies have begun to turn to the field of new media networks. Europe, Japan and developed countries such as the animation industry development history tells us that the animation industry development not only is relying on the overall planning of the industrial chain, rational distribution, but also the full use of the Internet in big data, the development of new media technology to build a platform for the development, transformation and upgrading Industrial operation model.

Under the background of the big data era, based on the regional characteristics and traditional national culture of Jilin Province, this paper focuses on the application of big data technology in the design and development of animation, cultural and creative products in different links. With big data technology as the guide of product design, the paper puts forward innovative design ideas and methods for the design of animation and cultural and creative products in Jilin Province to construct and develop the IP effect in this field, thus enhancing the competitiveness of Jilin Province in this field and solving the current problems in the development of the animation and cultural and creative industries in Jilin Province.

In order to solve the impact of actual construction projects on the existing surrounding environment, the impact and vibration of the impact on the existing railway subgrade stability caused by the construction of the bridge foundation are analyzed. Based on the actual case of the construction project of No. 37 main pier across the Jiaoji Railway Main Bridge at Binlai expressway, the influence of the impact holing on the adjacent railway is analyzed. The influence range of the construction vibration is based on the Chinese Seismic Intensity Scale (GB/T 17742-2008) and Safety Regulations for Blasting (GB6722-2014), and taking the maximum velocity allowable value as criterion, the minimum safety range of impact drilling is obtained. Using the theory of small hole expansion to calculate the influence of the effect of soil compaction, the minimum allowable value of safe distance for the Construction technology of impact forming hole is considered 6.5m; in addition, based on the numerical simulation of nonlinear time history analysis, a reasonable exciting force parameter is given for practical engineering. The influence of impact amplitude A and impact frequency f on construction safety distance is analyzed. The results show that: The minimum safety distance of impact drilling is linear with the increase of impact amplitude A. When the impact frequency f is greater than 10Hz, the minimum safety distance tends to a fixed value as f increases. The results of this study guide the actual construction of the field, it guarantees the normal traffic of the Jiaoji Railway and provides a theoretical support for similar projects.

In this paper, the effect of SiO₂ particles on electrical properties of superhydrophobic antiflash coatings was studied, which electrical properties include, the volume resistivity (ρ_v), the electrical strength (U_B), relative permittivity (ε_r), and the dielectric dissipation factor (tanδ). This kind of superhydrophobic coating uses modified SiO₂ and TiO₂ particles to construct micro-nano composite structures on the surface of FEVE fluorocarbon resin, and its surface has superhydrophobic characteristics. The results show that, with the addition of 5um SiO₂ content, ρ_v of the coating showed a trend of first increasing and then decreasing. The amount of 20 nm SiO₂ particles added has little effect on ρ_v. The content of 5um and 20 nm SiO₂ has little influence on the U_B of the coating. With the increase of 5um and 20 nm SiO₂, ε_r and the tangent of tanδ show an increasing trend. Compared with 5um SiO₂, 20nm SiO₂ has less influence on tanδ. The addition of 80nm SiO₂ has obvious significantly adverse effects on the four electrical properties of the coating.

The characteristics of the fault system are analyzed by using the 3D method and the combination of well-seismic and break-point method. The structural model is established by using the combination of logging and seismic data, to guide the adjustment of oilfield development. The results show that the fault combination, fault orientation and Extension Direction are obviously different from those before, and the large structure pattern of the study area has not changed, a structural model based on the combination of logging and seismic data, which is faithful to the well point data and retains the relative trend of seismic data, is better than the model based on logging data, it's more like an underground structure.

In this paper, different morphologies of diatomaceous earth (disc, cylindrical) were purified, and characterized by SEM, BET and pore size distribution, and moisture absorption and desorption tests were carried out. The results show that the humidity control performance of the cylindrical diatomite sample is better than that of the disc-shaped diatomite sample. Its 24h moisture absorption, 24h moisture release, volumetric moisture content ratio, average volumetric moisture content and other indicators all exceed Disc-shaped diatomite samples; the specific surface area of cylindrical diatomite samples is higher than that of disc-shaped diatomite samples, and the pore size distribution is more reasonable. Combined with the analysis of humidity control performance, cylindrical diatomite samples are more suitable As an excellent humidity control material.

This paper introduces the current situation of drinking water sources in Hubei Province, and points out that in the new period of harnessing the Yangtze River, the drinking water sources are faced with prominent contradictions such as low annual water consumption and prominent non-point source pollution. At the same time, the emergency standby water source is insufficient, and the water production technology of water supply enterprises needs to be improved. In order to ensure the optimal allocation and rational utilization of water resources, some suggestions are put forward, such as controlling the non-point source pollution system, actively promoting the construction of standby water source, and timely upgrading the water supply treatment process of water plants.

There are many factors that affect the safety of transport ships in the plateau reservoir area, which makes it difficult to allocate weights reasonably, and a large amount of single factor information is submerged. A fuzzy comprehensive evaluation model using improved AHP (AHP) is proposed, the advantages of the model are explained, and the method of constructing the model is introduced. The practicality of the model is verified through examples, and the results show that the model can scientifically and reasonably assess the safety risks of ships, and provide a reference for ship management companies and maritime safety bureaus to improve management methods.

BIM visualization 4D technology is applied to residential decoration and decoration construction sites, to establish Project and Revit model perspective analysis through Autodest Navisworks software, and make personalized modifications according to the different needs of customers to meet the current internal needs of fashionable buildings and dynamic decoration.

The 12.5m deep water channel project under Nanjing of the Yangtze River is a national key project. Based on the hechangzhou waterway section of the project, combined with the characteristics of water depth, strong wind, rapid flow and high wave, aiming at the problems such as short construction time, difficult instrument embedding, easy damage and low data collection efficiency, field monitoring test is carried out to monitor the foundation of submerged dike structure in the construction process The lateral displacement of deep soil mass, clear its development law, provide a strong guarantee for safe construction.

The research on the dynamic characteristics of soft clay under cyclic loading has high value. This paper takes Ningbo saturated soft clay as the research object and uses the GCTS true triaxial test system to analyze the effects of consolidated confining pressure and cyclic deviator stress on the axial cumulative strain. The experimental results found that when the number of vibrations and the cyclic stress ratio are the same, the axial cumulative plastic strain increases with the increase of the consolidation confining pressure. When the dynamic stress amplitude is the same, the axial cumulative strain decreases with the increase of the consolidation confining pressure. Under different confining pressures, as the number of vibrations increases, the cumulative axial strain increases. The development law of axial cumulative strain under different cyclic stress ratios is inconsistent, and there is a critical cyclic stress ratio. The experimental results provide a certain reference for engineering seismic design.

In actual engineering, when the soil element is subjected to load, the stress state will change accordingly. In this paper, undrained triaxial stress path tests for Ningbo reshaped saturated soft clay under different confining pressures are carried out. The test uses the GDS bidirectional vibrating triaxial instrument. The stress path dependence of saturated soft clay is studied. The stress-strain relationship and undrained shear strength under different stress path conditions are mainly analyzed. The test results show that the stress-strain relationship of the stress path test is obviously non-linear, basically strain hardening. The stress-strain curves of saturated remolded soft clay under different stress paths and consolidation pressures can be expressed in hyperbolic form. The initial stiffness E0 basically increases with the increase of the deflection angle of the stress path. The test results have certain reference significance for foundation pit and tunnel engineering.

Based on consumers' purchase intention, this paper obtains the utility function of carbon emission sensitive heterogeneous consumers and establishes a two-level supply chain model composed of the owner and the contractor under the government subsidy. Based on the principle of maximizing the profits of each member of the supply chain, the optimal pricing, incentive intensity and emission reduction effort level of the owners and contractors are obtained. On this basis, the influences of government subsidies, customer composition ratio and carbon sensitivity on the owner's optimal decision are analyzed. The results show that, with the increase of government subsidies for the contractor emission reduction costs, the proportion of carbon emission-sensitive consumers and the carbon sensitivity of consumers will increase, and the market demand will be increased, which will not only improve the profits of owners and contractors, but also the contractors' emission reduction efforts. It can provide decision-making reference for enterprise product pricing, emission reduction and government subsidies.

The freezing method is often used in underground excavation projects with high requirements for water stop and support. However, with the increasing complexity of the project, the freezing form is becoming more and more complex, and it is difficult to calculate the temperature field law by theoretical analysis. As a powerful simulation method, numerical calculation can be used to simulate the development of temperature field in complex horizontal freezing engineering. Based on the horizontal freezing construction of a subway connecting passage, this paper analyzes the development characteristics of horizontal freezing temperature field, and the results are in good agreement with the measured data. It is proved that the numerical simulation method can be used to simulate this kind of project, and the results can be used to guide the design and construction of related projects.

Artificial freezing method is commonly used in underground engineering excavation, such as mine, foundation pit and subway. The problem of post-construction thaw settlement has attracted more and more attention, but it is difficult to calculate the development law of thaw temperature field of complex frozen curtain by analytical method. Therefore, this paper adopts numerical method to study this problem. In this paper, taking the horizontal freezing construction of a subway connecting passage as an example, the development law of temperature field in the melting process is analyzed, and the results are basically consistent with the measured data. As a general means, numerical simulation is feasible to simulate the development law of temperature field in horizontal melting of complex curtain. The results of this paper can be used to guide the design and construction of artificial freezing.

After freezing construction, the damage caused by thawing settlement mainly comes from the displacement and settlement of strata, which leads to uneven settlement of underground pipelines and surface buildings in the project area. In this paper, based on the three-dimensional finite element analysis, the settlement displacement field of artificial frozen soil in a subway connecting passage is analyzed, and the parameters such as elastic modulus, density and specific heat change with temperature are considered in the model. The change of mechanical parameters in the soil layer is given by the temperature field, which makes the mechanical parameters of each point in the soil layer different. In addition, the temperature field of the soil layer changes with time, and finally makes the mechanical parameters change point by point, so as to ensure that the simulated melting and settlement calculation process is more in line with the actual working conditions. The calculation results of settlement displacement show that the settlement displacement field of soil layer changes nonlinearly with time and space. The research results of this paper provide reference for the position and time node of the control measures of thawing settlement.

in this paper, the principle of elastic time history analysis and the selection of seismic wave in time history analysis are briefly described; the elastic time history analysis of a super high-rise building is carried out by using the SATWE software of PKPM. The analysis results show that the base shear force and other indexes of the structure meet the requirements of the code under the action of 7-degree multiple intensity earthquake, and can meet the seismic design standards of the current seismic code in China.

With the gradual maturity of sewage treatment technology, constructed wetlands are increasingly employed to treat sewage. In residential areas where people live, there are concentrated sewage discharges. Therefore, the author proposes constructing several small movable constructed wetlands in the community to treat domestic sewage in the community. A 40 cm× 40 cm model was established to simulate the removal effect of pollutants. The influent concentrations of simulated COD, NH₄⁺-N, NO₃⁻, TP are 96.01 mg/L, 18.23 mg/L, 14.13 mg/L, 3.00 mg/L, respectively, and the outlet concentrations are 18.25 mg/L, 5.51 mg/L, 3.12 mg/L, 0.32 mg/L, the removal efficiency reached 80.99 %, 69.78 %, 77.92 %, 89.33 %, with good simulation effect. It provides a theoretical basis for the construction of constructed wetland.

Based on the hydrological data of Daicunba Hydrological Station of Dawen River from 1966 to 2017 and the meteorological data of surrounding stations, this paper analyzes the characteristics of the interannual variation of rainfall and runoff in the basin, and discusses the effects of rainfall and human activities on runoff. The results show that: (1) Rainfall and runoff in the Dawen River Basin showed an insignificant upward trend, with rising rates of 0.9541mm/a and 0.5398mm/a respectively; (2) Rainfall has a cycle of 4, 7, and 22 years, of which 22 The annual cycle is the main cycle, and the runoff has a cycle of 5, 7, 18, and 22 years, of which 22 years are the main cycle, and the main cycle of rainfall and runoff is consistent; the rainfall mutation point occurred in 1997 and 2002, and the runoff mutation point occurred in In 2002, the runoff had a significant increase trend after the sudden change; (3) According to the sudden change point of the runoff, the study area was divided into the base period (1966-2002) and the change period (2003-2017), so as to obtain the change of human activities on the runoff. The contribution rate is 60.6%, and the contribution rate of rainfall to runoff is 39.4%, indicating that the runoff of the Dawen River Basin is mainly affected by human activities.

Aiming at the problem that the current literature search algorithms only provide literature clues and original texts, which can not realize the analysis and evaluation, it is the formal comparison and cannot compare the actual contents of new papers and existing literatures; the objective programming target algorithm is introduced to calculate the "copy ratio" of the substantive content by minimizing the deviation between the objective function and the target value; small sample verification is carried out It is feasible and can open up a new idea for the upgrading of literature search tools.

Since the 21st century, the global warming trend has attracted the attention of the general public. Global temperature changes have caused many extremely severe weather events. This paper uses the meteorological data of 20 stations in the Huai River Basin from 1960 to 2017, combined with the historical records of meteorological disasters, and uses the SPI index to analyze the temporal and spatial distribution of meteorological drought. The conclusions are as follows: (1) SPI has a 14a main cycle and 4a, 5a, 6a, 11-12a and 22-24a secondary cycles. (2) The evolution characteristics of SPI show that the annual scale, spring, autumn, and winter increase at different speeds, and decrease in summer.

Graphite deposit is important ore in Huili County, Sichuan Province. It is located in the middle part of the Kangdian axis and the middle part of the Kangdian basement fault uplift zone. The graphite deposit is located in the strata of the Dayingshan Formation of the Lower Proterozoic Hekou Group. The deposit belongs to sedimentary metamorphic graphite deposit formed under the dual factors of regional and thermal contact metamorphism. The ore body is strictly controlled by horizons. Graphite is composed of migmatized graphite quartz schist ore and migmatized graphite schist ore. The former is of the main type and the latter to the second type. Through comparative analysis of metallogenic geological and geophysical characteristics, it is considered that the gold rain graphite deposit is influenced by strata, structure, magmatic rocks, metamorphism, migmatization and other factors.

For this paper, the VRP model on the total cost minimization of fixed cost, transportation cost and penalty cost is developed under the constraint of the delivery time satisfaction function for the characteristics of community group purchasing. On the genetic algorithm optimization, an elite retention mechanism is added, a partial crossover rule is used to design the crossover operator, and the examples are tested. The results show that solving the total cost function can effectively reduce the cost, and the improved genetic algorithm has good computational speed and convergence. At the same time, good satisfaction was obtained, indicating that the company cannot neglect the customer satisfaction experience while pursuing the minimum total cost, which provides a decision reference for achieving the balance between the two.

In the highway maintenance work area, how to reduce traffic congestion and traffic accidents caused by vehicle changing lanes has become a continuing research issue. This research focuses on the lane-changing behavior of vehicles in the highway maintenance work area. By changing the lane-changing trajectory of vehicles under different lane numbers, it can intuitively understand the influence of different lane numbers on lane-changing characteristics. Studies have shown that when the number of highway lanes increases, the distance between the starting point of the vehicle lane change and the highway maintenance work area will increase. At the same time, the probability of changing lanes in front lanes that are barrier-free and does not need to change lanes decreases as the number of overlapping lanes increases. Under the condition of the same number of lanes, the closer the distance between the vehicle and the obstacle lane, the more convergent the lane-changing trajectory of the vehicle, and the probability of lane-changing greatly increases.

In order to improve the safety of expressway maintenance work area at night, taking the maintenance work area of two-way four lane Expressway in Anhui Province as an example, the traffic characteristics of the maintenance work area at night are analysed, and the variation characteristics of vehicle speed in the maintenance work area are studied, and the main factors affecting traffic safety are obtained. Based on the traffic flow theory and Greenshields speed density-linear relationship model, this paper analyses the correlation between the speed and traffic capacity in the maintenance work area. Through the simulation by VISSIM software, the speed limit value of the expressway maintenance work area in the day and night is obtained, which provides an important reference value for the expressway maintenance operation.

This article has been retracted by IOP Publishing following an allegation that raises concerns this article may have been created, manipulated, and/or sold by a commercial entity. In addition, IOP Publishing has seen no evidence that reliable peer review was conducted on this article, despite the clear standards expected of and communicated to conference organisers.

The authors of the article have been given opportunity to present evidence that they were the original and genuine creators of the work, however at the time of publication of this notice, IOP Publishing has not received any response. IOP Publishing has analysed the article and agrees there are enough indicators to cause serious doubts over the legitimacy of the work and agree this article should be retracted. The authors are encouraged to contact IOP Publishing Limited if they have any comments on this retraction.

Retraction published: 23 September 2022