bluuebunny/crossref_metadata_2025 huggingface dataset:
Experimental Characterization of Positive and Negative Dielectric Constants and Artificial Anisotropy of Meta-materials in the Microwave Range
Authors: Dankov Plamen I.
Published: August 2020

This paper could be considered as a part of the invited talk “Metamaterials and Their Characterization in the Microwave Range” presented on the 8th International Workshop and Summer School on Plasma Physics (IWSSPP’2018, Kiten, Bulgaria), which has been dedicated to the classification, development, characterization and main applications of the metamaterials as one of the key issues of the modern technologies in the microwave, terahertz and optical regions. The experimental characterization of the actual equivalent dielectric parameters of the engineered artificial metamaterials is an important task in their design, nevertheless the existing relatively good correlation between the numerical simulations of these materials by 3D simulators and their measurements. The aim of the presented investigations is to give a helpful comparison between the most popular characterization methods based on free-space, waveguide and resonance measurements in the microwave range. The description of these methods has been based on the following principle: different metamaterials with surface metal inclusions have been selected and their main characteristics – equivalent dielectric constants in different directions (dielectric anisotropy) and the equivalent conductivity have been compared. A special attention has been directed to the description of measurements of positive and negative values of the permittivity, detection of artificial magnetic properties and resonance behaviour of the conductivity of the considered metamaterials.
Electromagnetic Modelling and Operation Analysis of Virtual Synchronous Machine for Frequency Response
Authors: Yuan L , Pan H N , Wang Z J , Wang F , Yuan M L
Published: August 2020

Virtual synchronous generators (VSGs) utilizing renewable energy sources (RESs) have been proven to be an appealing solution for overcoming the challenges of renewable energy sources (RESs) consumption in power systems. In order to address these issues, researches have been developed to improve the dynamic characteristics of VSG power systems. However, most of the studies at home and abroad focus on the negative impact of VSGs on the grid voltage, and few on the frequency, safety and efficiency of VSGs. The first part of this paper focuses on the VSG’s electromagnetic detail model with the ability to support the system voltage and frequency deviations, the second part discusses the mathematical investigation on its response as a VSG. Finally, according to the technical requirements of the power grid, mechanical and electromagnetic loads are simulated, the influence of service life is analyzed, and design suggestions are put forward.
Analysis of a SVC Device Filter Capacitor Bank Circuit Breaker Explosion
Authors: Quan Jiexiong , Wen Caiquan
Published: August 2020

When SVC device is in operation mode, it can provide fast dynamic reactive power compensation for the system when the power grid is disturbed greatly, and it can improve the voltage stability of the system. With the growing popularity of SVC devices in China, it is particularly important to study the faults of SVC devices in the process of operation. In this paper, the recent explosion of filter capacitor bank breaker in SVC device of a substation which was put into operation earlier in China is analyzed in detail. Through the inspection of equipment after failure, combined with the background of computer monitoring system, relay protection, and fault recording, the failure process is analyzed, and finally five preventive measures are put forward. It can provide guidance for the operation and maintenance of other station capacitor bank breakers, especially for the station capacitor bank breakers installed with SVC device, so as to ensure the safe and stable operation of the power grid.
Model building and simulation for intelligent early warning of long-distance oil & gas storage and transportation pipelines based on the probabilistic neural network
Authors: Kong Weiwei , Yu Jia , Yang Jia , Tian Tao
Published: August 2020

In order to solve the potential safety hazard of long-distance oil and gas pipelines, an intelligent early morning warning model is constructed and simulated based on probabilistic neural network in this paper. The backpropagation (BP) networks and the probabilistic neural networks (PNNs) are used to process the collected abnormal data and build the early warning model. The early warning model is simulated for its accuracy in the computer and its feasibility is verified. The intelligent early warning model is built, preparing the groundwork for the subsequent generalization and application.
An empirical study on the relationship among perceived value, satisfaction and behavioral intentions of battery electric vehicle user in China
Authors: Huiming Du , Yuning Wang
Published: August 2020

With the rapid development of battery electric vehicle, it has a profound impact on the driving behavior and habits of users. However, studies on the evaluation and users’ behavioral intentions of battery electric vehicle are rare. To promote the further development of battery electric vehicle, a better understanding of battery electric vehicle users is needed. This paper aims to develop a model to investigate the relationship among perceived value, user satisfaction and behavioral intentions of battery electric vehicle. Specifically, we divide perceived value into two dimensions of functional value and symbolic value. Data was collected through questionnaires from battery electric vehicle users in major cities in China. The analysis results of the structural equation model indicate that: 1. the functional value and symbolic value have a direct positive impact on battery electric vehicle user satisfaction and the symbolic value palys a greater role; 2. the functional value and symbolic value have a direct positive effect on the behavioral intentions of battery electric vehicle users; 3 battery electric vehicle user satisfaction and behavioral intentions have a high positive correlation.
Performance Analysis on Combustion and Heat Transfer of the Ship Power Plant
Authors: Liu Lili , Zhang Liyang
Published: August 2020

Study results on the supercharged boiler numerical simulation are on the boiler, convection tube bundle or the super-heater. These study subjects in a single model, and simplified the boundary condition to a certain extent. This paper takes the boiler as a whole research object. On the furnace chamber for combustion simulation, using the profile boundary information file boundary condition setting, faithfully transmitting boundary parameter spatial distribution. Followed by the simulation of heat transfer between the convection tube bundle and super-heater modules, we can get a real fluid flow and heat transfer condition, thus reacting to the complex heat transfer and flow inside of boiler, knowing the distribution of temperature, speed, pressure and other parameters. We can also see the change rule of the combustion and heat transfer processes in that supercharged boiler. Then we discuss the impact of the not uniform heat load on the convection heating surfaces, and preliminary analyzes the mechanism of combustion and heat transfer in supercharged boiler.
Economic Evaluation of Storage System in a Multi-energy System
Authors: Gao Shiqiao , Chen Jizhong
Published: August 2020

The integrated energy system, is to comprehensively plan, coordinately control, intelligently dispatch and multiply interact with multiple energy flows such as cold, heat, power and gas, which has broken the existing models of individual plan, design and operation of each energy supply system, and becomes a new model of future energy utilization. From the economic viewpoint, the energy storage system plays a quiet important role in this kind of grid structure. This paper presents a platform to assess the economic impact of different energy storage capacity and type on a district multi-energy grid operation cost. A multiple time-scale cooperative optimization is firstly proposed for the control optimization of energy storage, cold storage and heat storage to fulfill the minimization of total operation cost of integrated energy system. Then the economic benefits of different battery types and capacity are compared. For each scenario, the battery characterizes are also analysed and compared.
Research on the Industrial Transformation of Resource-based Cities: Take Hainan Province as an Example
Authors: Wang Lin
Published: August 2020

Industrial transformation and upgrading is a necessary condition to realize the sustainable development of resource-based cities. This paper studies the industrial transformation of Dongfang, Hainan Province. In view of the strategic goal of establishing ecological civilization society and realizing the development mode of green economy in China, the industrial transformation of resource-based cities with the advantages of mineral resources becomes an inevitable trend. Based on the SWOT analysis, the author analyzes the industrial adjustment of Dongfang, and puts forward the target and related measures of industrial transformation. The research of this paper has both rich theoretical and practical significance for improving the efficiency of industrial transformation.
Research on Multi-Factor Ice Disaster Risk Evaluation Model for Transmission Line
Authors: Gu Kaikai , Peng Zhonghan , Xu Xiaolu , Wu Qirui , Chen Kai , Song You
Published: August 2020

With the development of the transmission line scale and the improvement of the voltage level, the height and span of the tower are increasing, and the ice disaster occurs frequently in some areas, which has become an important factor affecting the security and stability of the power grid. Based on the analysis of the ice and ice flashover mechanism, this paper firstly discusses ice disaster influencing factors from three main angles, such as, the potential fault of transmission line, operation and maintenance characteristics and meteorological conditions, and then uses multi factor classification method to build the ice disaster risk evaluation model for transmission line. Further, taking the 220kV and above transmission lines in a certain area of South China as a research object, this paper evaluates all the lines and towers ice disaster risk, obtains the lines or towers with high risk level using the model, and the evaluation results have been verified on site. Finally, combined with the rating of risk evaluation factors, this paper formulates a special anti-icing measure to ensure the safe and stable operation of transmission lines.
Calculation and analysis of the storage capacity configuration of Shanxi power grid based on time series simulation
Authors: Zhao Jun , Chang Xiao , Zhang Shifeng , Fan Rui , Gao Le , Wang Jinhao
Published: August 2020

In recent years, with the energy transformation and the continuous innovation of new energy technology, the installed capacity of new energy continues to increase, the high proportion of new energy access increases the peak pressure of the power grid, but also increases the possibility of de-electric power. As a key solution, energy storage and wind power and other new energy in-depth integration, can effectively improve the power grid adjustment capacity, to ensure the benefits of new energy generation. Using the time series production simulation method, aiming at the utilization rate of new energy, this paper calculates the principle of energy storage configuration in different regions of Shanxi Province, and provides theoretical support for the analysis of energy storage configuration in Shanxi Province.
Research on the Sustainable Development Strategy of China’s Petroleum Resource-Based City Based on Entropy-weight TOPSIS Method
Authors: Liu Yi , Liu Junjun , Sun Zhen
Published: August 2020

This paper takes 8 typical petroleum resource-based cities in China, such as Panjin City, Songyuan City, Daqing City, Dongying City, Puyang City, Nanyang City, Qingyang City, and Karamay City, as the research objects, applies the entropy-weight TOPSIS method to analyze and evaluate the sustainable development level and puts forward strategic suggestions on how to improve the sustainable development of petroleum resource cities.
A review of materials and their future development trends for lithium ion battery anodes
Authors: Chen Weichen
Published: August 2020

With the development of electric vehicles and clean energy, the demand for lithium batteries as an important energy storage system has increased significantly in the past decades. Anode, an indispensable part in lithium batteries system, is currently mainly selected from carbon-based materials, silicon-based, tin-based alloys, and metallic lithium materials. Lithium battery with traditional carbon-based material can basically meet the requirements of most current consumer electronics products. Silicon-based and metallic lithium materials have greater development potential in terms of high energy density anode. This article introduces the carbon-based materials, silicon-based, metallic lithium materials and their common modification methods that have been widely studied at the current stage and discusses the future development trends of various anode materials.
Research on Power Control Method of Oscillating Float Type Ocean Wave Energy Power Generation
Authors: Hongda Ma
Published: August 2020

With the development of the economy, human beings’ over-utilization and dependence on traditional energy sources such as oil, coal, and natural gas have gradually triggered a global energy crisis. Therefore, the use of renewable energy has received great attention from people, and the ocean that accounts for the total area of the earth has first come into the sight of developers. Wave energy has the advantages of wide distribution, large reserves, and diverse acquisition methods, and has become one of the most promising marine energy sources. However, the research on wave energy is currently in its initial stage and its development is relatively lagging. It is a renewable energy with great potential in order to increase the power generation of wave power systems. This article first introduces the current distribution of wave energy and outlines the principle of wave power generation. In view of the calculation method of wave force and the shortcomings of the current floating-type power generation system, a new type of oscillating floating-type wave power generating device is designed, which can realize the maximum power tracking control to a certain extent.
Operational Optimization of Integrated Energy System Based on Coordinated Complementary of Cold, Heat and Electricity Loads
Authors: Jiantao Kou , Shuquan Li , Kunpeng Zhao , Yongli Wang , Jianfeng Wei , Fuhao Song , Danyang Zhang , Feifei Huang
Published: August 2020

Integrated Energy Systems (Integrated Energy System, IES) to pluripotent and complementary energy ladder as the core, will greatly improve the system’s energy efficiency, to achieve a variety of complementary energy flow optimization. By establishing a cold-heat-electricity integrated energy system, taking the lowest total operating cost of the system as the objective function, considering the equipment model constraints and power balance constraints, the day-to-day load simulation is used to optimize the economic operation of the integrated energy system; at the same time, the system operates in winter and summer. The operating conditions vary greatly, and the quarterly adjustment operation mode is adopted, and the branch and bound (BaB) algorithm is used to solve the optimization model. The simulation results show that the energy supply of the system is balanced, the “source-charge-storage” complementarity is strong, the system operates flexibly, cost-effectively, and at the same time, the system emits less polluting gas, which is beneficial to environmental protection.
Planning Optimization of Integrated Energy System Considering Economy and Integrated Energy Efficiency
Authors: Wang Qingwei , Wang Yongli , Ma Yuze , Ma Yang , Dong Huanran , Qi Chengyuan , Song Fuhao , Huang Feifei
Published: August 2020

The integrated energy system is the concrete realization of the energy Internet in the region by coupling various energies and carrying out multi-dimensional coordinated management and distribution of various energies such as electricity, gas, cold and heat. An Integrated energy system planning method is proposed. Firstly, a heterogeneous energy network model of a typical integrated energy system is developed. Aiming at minimizing the total operating cost and maximizing the integrated energy efficiency of the integrated energy system, NSGA-II algorithm is used to realize optimization in MATLAB program. Through the TOPSIS method, multiple sets of solutions are compared and analyzed, thus the optimal planning scheme of the system is obtained quickly and accurately. Through optimization calculation, the optimal capacity allocation and operation strategy of major equipment can be obtained. On the premise of meeting users’ various energy demands, the system investment and energy consumption cost can be reduced to the maximum extent, and the efficient utilization and sustainable development of various energy sources can be promoted.
Research on Green Logistics Development in Guangdong Province from the Perspective of Sustainable Development
Authors: Guo Haihong
Published: August 2020

As the largest province in China’s total economy, Guangdong’s logistics industry has developed rapidly and has made important contributions to the development of regional economy. In this context, promoting the development of Guangdong’s logistics industry to green logistics as soon as possible and reducing carbon emissions are important ways to achieve sustainable development. By analyzing the current situation of the development of the logistics industry in Guangdong Province, this paper finds that there are deficiencies in the information level, transportation structure and park planning of the logistics industry. Based on the problems found, this paper puts forward some suggestions for the development of green logistics in Guangdong Province.
Evaluation of renewable energy resources abundance and spatial correlation analysis in Beijing
Authors: Sun Yaqing
Published: August 2020

Beijing is actively exploring the development and utilization potential of local renewable energy resources in order to speed up the adjustment of energy structure, implement clean energy substitution and build a modern green energy system in the capital. In this context, it is urgent to systematically analyze the status and characteristics of renewable energy resources in Beijing. Taking Beijing as the research area, this paper calculates the abundance indexes of solar energy, wind energy and biomass resources respectively, and establishes the renewable energy abundance evaluation model. Based on the spatial distribution characteristics of renewable energy resources in Beijing, the spatial correlation of renewable energy resources was tested. The results show that renewable energy resources in Beijing are generally characterized by “rich in the north and poor in the South” and “rich in the surrounding areas and poor in the center”. Among them, solar energy resources are relatively rich, wind energy resources are scarce with random distribution characteristics, and biomass resources are decreasing year by year. The research results can provide important reference for the development and utilization of renewable energy resources in different regions of Beijing.
Research on Pricing Mode of Overhead Transmission Line Adapted to 3D Design Development
Authors: Ying Du , Tiannan Ma , Chao Wang , Ping Zhou , Jiyuan Zhang , Mingyong Wan , Chao Chen
Published: August 2020

The construction and development of overhead lines is an important support for power grid companies to ensure the safe and stable supply of electricity. For a long time, the estimated budget, completion settlement and financial final accounts of overhead transmission lines are all priced according to the entire line. The project construction management and asset collection have not formed a refined management system. The lack of individual pricing based on the actual investment of different towers cannot be reflected. With regard to the actual cost level of each base, the accuracy of cost needs to be further improved. Therefore, we must innovate the pricing model, strengthen the lean management of the construction cost determination of overhead line projects, rely on the development and application of three-dimensional design, strengthen the construction of the “tower-oriented” construction cost determination system, reasonably control the project investment, and improve the investment efficiency level of the power grid construction.
Wave-induced stability of gassy seabed with different gas existing forms
Authors: Wu Zhanzhan , Liu Xiaoli
Published: August 2020

For highly saturated seabed soils, gas mainly exists in two forms: one is in the form of discrete small bubbles in pore water (referred to as “small bubble seabed”); the other is independent of the pore water, in the form of large bubbles surrounded by saturated soil matrix (referred to as “large bubble seabed”). For the two different kinds of gassy soil, based on different theoretical models, the wave-induced stability of gassy seabed has been investigated using finite element method. It has been shown that the wave-induced momentary liquefaction depth of the large bubble seabed is less than that of the small bubble seabed. However, the shear failure depth of the large bubble seabed is greater than that of the small bubble seabed, and the difference could be up to about 80%.
The Research of Coordination Extraction from the Stope Gas with Partition and Time-sharing
Authors: Hong-wei Yang , Zhi-liang Qian
Published: August 2020

Based on the analysis of the distribution characteristics of the S-type overburden spatial crack field in a 3322 working face of a mine and the actual observations, it adopts comprehensive drilling modes such as ground drilling, high-drainage roadway drainage, and goaf buried pipe. “What time, where?” How much gas is extracted, and the effects of ground drilling, high-drainage roadway drainage, and underground pipe drainage in the goaf were evaluated, respectively, through space cracks in the S-type overburden The time-division extraction mode is adopted in the site, including comprehensive extraction methods such as high-draining lanes and buried pipes in the mined-out area. The gas extraction in the 3322 working face of the mine has reached the standard, ensuring safe and efficient mining at the working face.
Electric field characteristics of X-ray detection and safety protection in live work of transmission lines
Authors: Xianhui Cao , Kejian Ouyang , Weike Liu , Yi Xie , Miao Yang , Chao Feng , Yi Fu , Long Zhan
Published: August 2020

Hidden defects in transmission lines can be detected by X-ray. Through the simulation of different voltage/current tests in the laboratory, the live detection test of digital X-ray detection equipment was carried out and the detection tests under the live condition of 110kV transmission line carried by unmanned aerial vehicle, the maximum tolerable voltage of X-ray digital imaging equipment during live operation was determined. By using the electric field finite element simulation, the affected field intensity detected by the equipment is 360kV/m, and the spatial field intensity distribution of ac transmission lines with different voltage levels is given, which provides a reference for selecting reasonable electric field shielding measures for the live operation of X-ray digital imaging equipment.
Using a network DEA model to assess the energy efficiency of regions in China
Authors: Wu Geng , Hu Yichung , Kong Peiyi
Published: August 2020

This paper assesses 30 provinces’ data in China by using a network DEA model with undesirable output. The results denote that the proposed model could evaluate the internal energy consumption well. And the main cause of the energy inefficiency is environmental inefficiency. Therefore, China’s provinces should tighten restriction on CO2 emissions and reduce their dependence on fossil fuels by using more green energy.
Planning and Optimal Scheduling Method of Regional Integrated Energy System Based on Gray Wolf Optimizer Algorithm
Authors: Qiu Jifu , Chen Ming , Wei Zhen , Xu Zhengqing , Li Yukai
Published: August 2020

For the regional integrated energy system (RIES) with multi-energy complementary, it is key to plan and optimize scheduling, which can improve energy efficiency. This paper focuses on the planning and scheduling of the RIES with self-provided waste incineration power plant. A bi-level mathematical model of the RIES with electricity, heat, cooling and gas interconnection is built. The upper level takes the minimum annual comprehensive cost as the optimization objective to find the optimal configuration. Based on the configuration scheme provided by the upper level, the optimized scheduling scheme under the economic and environmental indicators is developed by using some constrains, such as the supply and demand balance and equipment output operation. At the same time, the policy subsidy of self-provided waste incineration power plant and the transaction cost of pollutant emission are considered in the optimal scheduling. Then the gray wolf optimizer algorithm is proposed to solve the bi-level optimization problem. The effectiveness and superiority of the planning and optimal sheduling model proposed are demonstrated by analyses in typical scene.
Research on Sports Tourism Promoting Sustainable Development of Coastal Rural Areas Based on Fuzzy Fault Tree
Authors: Shi Li-zhen , Li Xiao-dong , Cao Run-feng , Lei Meng-meng , Zhang Xiao-li
Published: August 2020

This paper discusses the problems and countermeasures of sports tourism in promoting sustainable development of coastal rural areas through literature data and fuzzy fault tree analysis. Based on the tourism supply chain theory and the actual situation of coastal rural revitalization, analyze the possible reasons for influencing sports tourism to promote rural sustainable development, and finally establish a fuzzy fault tree. Problems in rural sports tourism include the lack of social capital that hinders the sustainable development and construction of coastal villages; the lack of diversified forms of sports tourism to revitalize rural areas; and the neglect of the construction of urban-rural blending areas in coastal rural sports tourism. Conclusions: sports tourism should adapt to the development of the rural economy and actively absorb social capital; establish a development-oriented thinking of poverty alleviation through sports, and use subjective initiative to enrich sports tourism; take advantage of the difference in endowment of sports factors and make full use of urban-rural blending areas.
Temporal and Spatial Distribution of Chlorophyll-a in Caotang River of Three Gorges Reservoir
Authors: Zhang Yongsheng , Li Haiying , Ren Jiaying
Published: August 2020

To study the formation of algae blooms in Caotang River, a tributary of the Three Gorges Reservoir, the authors set up six monitoring sites in Caotang River and Yangtze River to continuously monitor the concentration of chlorophyll-a for one year from July 2017 to June 2018 and analyzed the distribution of algae blooms. It is found that in the vertical direction, chlorophyll-a had a maximum concentration at 2.41 mg/m3 at the surface and a minimum concentration of 0.69 mg/m3 at the bottom. The algae blooms broke out in Caotang River from July to September 2017, and there was no significant difference in the concentration of chlorophyll-a during other periods. During algae blooms, the concentration of chlorophyll-a increased from downstream to upstream except for the source section. There was no significant difference in the concentration of chlorophyll in the middle and bottom water bodies. The Yangtze River has a lower concentration of algal toxin than that in the Caotang River. Excluding the source where algal toxin was not observed, this study found that the concentrations of algal toxin in the other three sections (CT01, CT02 and CT03) were at 0.42 ug/L, 0.56 ug/L and 0.83 ug/L, respectively.
Analysis of Rainwater Pipelines for Local Flooding Mitigation
Authors: Zhang Zhaoxiang , Yang Fan , Huang Yongzhou , Fu Yandong , Li Yanjun , She Lei , Zhou Yanyan , Zhang Bin
Published: August 2020

PCSWMM was used to perform hydrodynamic simulation. Effect of water level, slope and diameter of rainwater pipelines on local flooding was investigated at free discharge and submerged discharge respectively. Bernoulli equation was applied to theoretical analysis. Results showed that increase of pipe slope and diameter could improve drainage capacity of rainwater pipes at free discharge. Rising water level seriously restricted drainage capacity of rainwater pipes. However, at submerged discharge, pipe slope promoted the construction cost, but it had no effect on its drainage capacity. With the increase of diameter, drainage capacity of rainwater pipes increased. Main factors on drainage capacity of pipes were water head different between upstream and downstream, pipe diameter and roughness coefficient. Hence, it’s recommended that urban drainage system should properly control water level and increase pipe diameter at submerged discharge. The results are important implications for rainwater pipeline design to prevent local flooding.
Research on the Construction of New Transportation Infrastructure in Beijing
Authors: Xin Wu
Published: August 2020

This paper analyzes the development of new transportation infrastructure in Beijing by taking the utility tunnel as an example. The utility tunnel is a modern and intensive urban infrastructure that is constructed by integrating various engineering pipelines, such as electricity, communications, gas, heating, water supply, and drainage in the underground tunnel space of cities. The construction of the underground pipe gallery is conducive to ensuring the comprehensive utilization of the underground space of cities, which can meet the needs of continuous growth of roads and paths, and facilitate intensive management. This article focuses on the development of the construction of the utility tunnel in Beijing. Based on analyzing the development bottlenecks of the underground utility tunnel in Beijing, implementing scientific planning, realizing intelligent management of the utility tunnel and establishing the paid use system are put forward in order to provide solutions for promoting the development of the utility tunnel in Beijing and solving urban transportation problems, and to promote high-quality development of transportation in Beijing.
Cycle and Harm of Main Pollutants in Thermal System of Gas Turbiner
Authors: Ruqing Niu , Fengyuan He , Yunfei Jiang , Xinjing Tian
Published: August 2020

This project analyzes and studies the monitoring data of chemical water vapor in the operation of a gas steam combined cycle generator unit, discusses the accuracy, measurement error and the correlation among various water vapor indexes of the (hydrogen) conductivity, pH value, sodium content, dissolved oxygen, silicate root, phosphate root and other monitoring experiments in the water vapor quality monitoring work, and puts forward the condensate and water supply which are easy to be measured accurately. Based on the hydrogen conductivity of saturated steam, superheated steam and the conductivity of boiler water, estimated the chlorine content, ammonia content, pH value and other indicators of water (steam) at each sampling point, comprehensively judged the accuracy of water quality measurement, preventd serious deterioration of water vapor quality, and ensured that the thermal equipment is free from corrosion, salt deposition and scaling.
Analysis on Ecological Footprint of Agricultural Heritage Sites under Tourism Utilization: A Case Study of Nanfeng County
Authors: Dongjun Chen , Hongbin Xie , Jing Zhang , Luyuan Chen
Published: August 2020

Tourism is an important way to achieve dynamic protection and adaptive management for agricultural heritage sites. The balanced relationship between tourism development and protection of agricultural heritage sites is the key to the sustainable development of its tourism industry. This paper uses Ecological Footprint Model (EF) to evaluate the ecological state of a specific agricultural heritage site, namely Nanfeng County in Jiangxi Province, China. The result indicates that Nanfeng County showed a safe ecological state under tourism utilization in 2015. It inspires how to realize sustainable tourism of agricultural heritage sites: 1) ecological environment is the guarantee of sustainable tourism development; 2) develop tourism adaptively based on actual resource characteristic; 3) social economy and tourism development should promote mutually. This study provides a scientific case for ecology security evaluation and sustainable tourism development of Nanfeng County.
Current status of microplastics pollution in tianjin coastal waters
Authors: Zhu Jingwen
Published: August 2020

Microplastics (MPs) have home a global concern as well as climate change, ozone separation and ocean discrimination. In order to restore the distribution characteristics and influence factors of MPs in Tianjin coastal waters, the distribution of MPs in three sections of Tianjin office area was studied by using surface sampling, density usage separation and alternative microscopies. The size, shape and chemical composition of MPs were further analyzed. Our results show that the extent of MPs in the sea water samples were rang from 210 to 1170 particles . m−3 with a mean of 612 particles . m−3 in the three sections of the offshore area. Three shape types of MPs were present in the seawater samples, including slender fibers, irregular fragments and thin films. Fibers and fragments were predominant forms, which accounted for 52.1% and 46.8%, respectively. The particle size of the detected MPs was consistent with those reported by previous studies. The smaller the particle size, higher the content 55.3% MPs had particle size of less than 0.5mm. According to the microscopy analysis result, most of MPs in surface seawater samples showed a deep color (such as blue, black and red), and a few MPs showed colors of yellow, green and while. The main chemical components of MPs were analyzed by using infrared microscopy components were detected, including PP-PE, ABS, CE, EP, PA, PE, PET, PP, and PVC, with an order of PET >PP-PE >EP >CE >ABS >PE >PA >PVC >PP. The results demonstrated that the MPs pollution in the Tianjin offshore area was affected by the development of marine industries, such as marine fishery, port transportation, etc. In addition, the MPs pollution in the ocean was also affected by land-based sewage discharge due to the fact that Tianjin was an industrialized city with a large population density.
Study on Coupling Mechanism of Carbon-Water Symbiosis System and Regulation and Control of Water Resources in the Context of Regional Collaborative Development
Authors: Zhong Wei , Zhang Dong
Published: August 2020

In the aspect of theoretical research, the regional carbon-water coupling mechanism has not yet formed a complete conceptual framework, so there is an urgent need to build an academic system of the carbon-water coupling under a unified physical device. Therefore, based on the overall identification of the coupling mechanism of the water cycle and carbon balance, this paper systematically analyses the characteristics of carbon capture and release in the process of water resources and energy development, puts forward the connotation, symptoms and overall tasks of water resources allocation based on low-carbon development model, and constructs a technical framework supported by regional carbon-water coupling simulation and water resources allocation. The critical technical issues such as water resources allocation, model construction process, countermeasures and safeguard measures based on the low-carbon model. The safety early warning model of water quality and quantity in regional carbon-water symbiosis system is put forward, which provides a method reference for the regulation and control of local water resources.
Research on the Impact of COVID19 on Global Economy
Authors: Mou Jinjin
Published: August 2020

With the development of cosmopolitanization and globalization, dense population and large-scale population flow not only make the economy more integrated, but also make the spread of the plague more rapidly. The impact is unprecedented. The outbreak of COVID-19 has disrupted the Chinese economy and is spreading globally. The evolution of the disease and its economic impact is highly uncertain. Because of its high infectivity, high mortality and incubation period, the main preventive measures are to control social distance and isolation, which makes many economic activities impossible. Global GDP will fall by as much as 3%, while developing countries will be the hardest hit, as much as 4% on average, but some were more than 6.5% and world merchandise trade will plummet by 13% in 2020 due to the COVID-19 pandemic. This paper analyzes the macro economic impact of new coronavirus on the world GDP, merchandise trade (taking China as an example with other countries), and various industries, and proposes some countermeasures.
Research Status of Microplastics Pollution in Abiotic Environment in China
Authors: Wang Z H , Sun X J
Published: August 2020

With the continuous attention to the microplastics pollution in the world, since 2014, Chinese scholars have rapidly carried out a large number of microplastics pollution investigation and experimental research. This paper summarizes the research results of microplastics pollution in abiotic environment (ocean, land water, soil, atmosphere) in this stage, in order to provide support for the future research.
Community risk governance research review at home and abroad
Authors: Zheng Wen Zhang
Published: August 2020

Community safety is related to everyone. This article first analyzes the related concepts of community risk and understands the specific differences. Then by summarizing the current situation of community risk and emergency management at home and abroad, and comparing the research status at home and abroad, we can get the characteristics of community emergency management in China.
Temporal Variation and Trend Prediction of Carbon Storage in Subtropical Evergreen Broad-leaved Forest in Jiangxi Province Based on Remote Sensing Images
Authors: Qiugen Zhang , Ruan Ding , Jian Li
Published: August 2020

The dynamic change of forest carbon storage can be monitored by remote sensing technology because the change of vegetation index can reflect the dynamic change of forest carbon storage based on the remote sensing images. Combined with remote sensing estimation model of vegetation and soil carbon storage based on the remote sensing classification area data of subtropical evergreen broad-leaved forest in 2015, the vegetation and soil carbon storage and carbon density of subtropical evergreen broad-leaved forest in Jiangxi province from 1985 to 2015 was estimated by using the remote sensing image data of Jiangxi province from 1985 to 2015. The results showed that the carbon storage and carbon density of subtropical evergreen broad-leaved forest in Jiangxi province had shown an overall increasing trend from 1985 to 2015. The carbon storage of vegetation had increased from 0.1254 GtC in 1985 to 0.2092GtC in 2015, and the carbon density of vegetation had increased from 63.071t/hm2 in 1985 to 76.31 t/hm2 in 2015. The soil carbon storage had increased from 0.3820 GtC in 1985 to 0.5474 GtC in 2015, and the soil carbon density had increased from 185.99 t/hm2 in 1985 to 199.69 t/hm2 in 2015. At the same time, the change trend of carbon storage in subtropical evergreen broad-leaved forests in Jiangxi province from 2020 to 2035 was predicted. The vegetation carbon storage will achieve 0.2774GtC, 0.2969GtC, 0.3164GtC and 0.3359GtC in 2020, 2025, 2030 and 2035 respectively. The soil carbon storage will achieve 0.5020GtC in 2020, 0.5335GtC in 2025, 0.5650GtC in 2030 and 0.5965GtC in 2035 respectively.
Water Quality Monitoring and Standardization in China: A Review
Authors: Tan Jing
Published: August 2020

Water quality monitoring is very important for environmental protection. At the same time, it is also an effective detection method for pollution control. In this paper, we review the standardization of water quality monitoring and in China systematically. Then, the differences in water quality standards between China and foreign countries are analyzed. Moreover, the water quality monitoring methods are investigated. Finally, the conclusion and perspective are given.
Ecological Compensation Standard of Groundwater
Authors: Fu Yicheng , Cui Xiaoyu , Zhao Jinyong , Peng Wenqi
Published: August 2020

According to the characteristics of groundwater and the requirements of groundwater protection, the ecological compensation standard of groundwater is discussed. Based on the study of groundwater characteristics at home and abroad, combined with the existing ecological compensation research, the ecological compensation standard of groundwater is discussed based on fair water use. Based on the determination of water distribution, pollutant discharge permission and water use income, and based on the social equity mechanism and the cooperative game, the upper limit of agricultural water demand in Cheng’an County under the current development mode is calculated to be 400 million m3, the lower limit to be 34 million m3, and the average to be 32 million m3. The people’s Government of Cheng‘an county shall compensate the farmers for their water saving. The compensation standard is based on the economic benefits of agricultural water use. The total compensation amount is 236 million yuan. The compensation standard is 6720 ¥/ha according to the accounting of 35 thousand ha farmland area. The calculation results of the groundwater ecological compensation model are reasonable and easy to implement, which provides a theoretical basis for the implementation of groundwater ecological compensation in Beijing Tianjin Hebei region.
Feasibility analysis of waste humus soil for Urban Greening
Authors: Cao Lihua , Wu Jun
Published: August 2020

From the landfill site which was closed for 15 years,10mm sieved humus soil was extracted as test material, to build the wild plant simulation leaching system. The regularity of pollutant release and the migration of heavy metals were studied in the system, in order to explore the feasibility of using humus soil for urban greening. The test results showed that the pH value of the leaching solution is between 6.8 and 7.7; the COD value is basically stable between 40 mg / L and 75 mg / L; the concentration of NH3-N is less than 1 mg / L; Between 200mg / L, it mainly exists in the form of nitrate nitrogen. Total and Morphology Analysis of four heavy metals (Cu, Zn, Pb, Ni) showed that all the metals were able to achieve the soil environmental quality risk of soil pollution control standard for GB36600-2018 in the nature of the land of green space and square, and the proportion of exchangeable and carbonate binding states in the four heavy metal were small, meanwhile the dissolution and mobility were small. In conclusion, humus soil has the feasibility to use for urban greening.
Lithofacies composition and geological significance of black rock series: a case study from the lower Cambrian Qiongzhusi Formation in Huize area, eastern Yunnan province
Authors: Cheng Yong , Lu Ping , Nie Qi , Liu Zhennan , Liu Cong , Wen Yiming , Guo Yufeng , Wu Shili
Published: August 2020

Lithofacies is an important basis for the characterization of source rocks, shale oil and tight oil reservoirs and the evaluation of oil and gas reservoirs. In this study, a well-developed Qiongzhusi Formation section in Huize area was selected to study the lithofacies features and their evolution and the following conclusions are obtained. In the geological section, the lower part of the Qiongzhusi Formation black rock series is mainly composed of felsic fine-grained sedimentary rock (I) and dolomite or limestone (II). The middle part of the section is clayey felsic fine-grained sedimentary rock (I2), and the upper part is felsic clay rock (III2). Lithologic changes in Qiongzhusi Formation were controlled by terrigenous debris supply, hydrodynamic conditions and water depth. The felsic fine-grained sedimentary rocks formed when the water body was relatively deep in the early stage and the felsic clay rocks deposited when the terrigenous clastic supply was weakened in the middle to late stage have a high content of original organic matter, which is a favorable site for the evaluation of shale gas reservoirs.
Residents’ action response experiments on different travel modes under the external conditions of a metropolitan environment
Authors: Luan Xin , Cheng Lin , Wu Zixin
Published: August 2020

The residents’ action response experiments are a complex decision making procedure and a natural science question influenced by multiple indicators and the built environment. It can reflect the urban traffic pattern and resident travel structure at a micro level, which gives us the motivation for better understanding and revealing residents’ behavioral characteristics and influencing factors of different travel modes quantificationally and systematically from the metropolitan environment perspective (novelty). This is of great guiding significance and necessity for the implementation of transportation demand control, optimization of urban traffic system, daily travel decisions of metropolitans, traffic environment, especially in the current application of computer big data analysis techniques. In this paper, we give a discussion and exploration for analyzing the people’s action response problem on different travel modes with external conditions in a metropolitan environment.
Short-term load forecasting algorithm based on LSTM-DBN considering the flexibility of electric vehicle
Authors: Na Zhang , HanZhen Tao , YuTong Liu , Jia Cui , JunYou Yang , Wang Gang
Published: August 2020

Due to the rapid development of electric vehicles, the randomness of charging and discharging modes brings huge challenges to load forecasting. Considering the large-scale gridding of electric vehicles, a load combination forecasting algorithm is proposed in this paper which considers the flexibility of electric vehicles. Firstly, the user behaviors of electric vehicle are modeled based on Monte Carlo method. Secondly, different from traditional single forecasting models, the combination of deep belief network and long short-term memory net-work is used in order to improve the forecasting accuracy and calculation speed for the complex case. Thirdly, a dynamic weight distribution method is proposed to combine the two forecasting results. Finally, Numerical examples have been performed with the results proving that the proposed method outperforms the state-of-art significantly in load forecasting, and the combined model has a higher forecasting accuracy than traditional methods.