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The ever-increasing electromagnetic interference (EMI) pollution becomes an important issue in current environmental protection and human society. In this work, 3D BaTiO3(3DBT)@C porous ceramic framework was one-step fabricated by sol-gel method using environmentally friendly cleanroom wipers as template and calcined under inert atmosphere. Subsequently, epoxy (EP) resin was reversely incorporated into the above 3DBT@C network, resulting in the 3DBT@C/EP composite. Results showed that the cleanroom wiper was calcined and transformed into amorphous carbon within the 3DBT, leading to the excellent electrical conductivity of 3DBT@C. The reverse infiltration of EP maintained the successive 3DBT framework and excellent conductivity, thus endowing the 3DBT@C/EP composite with a good electromagnetic interference shielding effectiveness (EMI SE) as high as 36.6 dBꞏmm-1 at 10.2 GHz. The absorption mechanism of EMI prevailed the EMI SE due to the large Ohmic loss and porous 3D network, implying potential applications in flexile shielding materials.

Structural characteristics of electrical equipment are influenced by connected flexible conductors. In order to study the seismic performance of the double electrical equipment system (DEES) with flexible conductors, a simplified modeling method of the DEES with flexible conductors was proposed in this paper. The refined finite element model of the DEES with flexible conductors was established using ANSYS software. Its seismic response level was analyzed and compared with that of the standalone equipment. Besides, the impact of ground motion input was also investigated. The results show that the first two modal frequencies of the DEES will be reduced by the flexible conductor. The flexible conductor can reduce the seismic responses of the low-frequency equipment in the DEES, while it increases seismic responses of the high-frequency equipment. When the slack of the flexible busbar is greater than a critical value, the additional pulling force on the top of the equipment caused by the busbar can be kept at a low level, which is also related to the ground motion input.

Caries is one of the most common diseases in the human body, and its incidence is extremely high in both children and adults. Caries is also a chronic and developmental disease, and its sustainable development will not only seriously endanger oral health, but also endanger the health of the whole body. At present, some progress has been made in the research on the pathogenesis and prevention of caries, but there are still many problems to be solved. This paper discusses the etiology, treatment and prevention of caries, aiming to lay a foundation for the prevention and treatment of caries.

In this paper, hydroxyapatite coating was successfully deposited on ZK60 magnesium alloy surface by ultrasound-assisted electrodeposition method, and the macroscopic structure, chemical composition and corrosion properties of ZK60 magnesium alloy sample and HA coating were analyzed. The results show that the quality of ZK60 magnesium alloy surface coating is improved by ultrasonic power, and the HA coating is uniform, smooth and compact. XRD and FTIR analysis show that the main composition of the coating obtained by ultrasonic assisted electrodeposition is hydroxyapatite. The results show that ultrasonic treatment is beneficial to the corrosion resistance of SBF solution.

This paper proposes a sustainable agricultural development index (SADI) and a hybrid grey model for measuring the changes in agricultural sustainability over time. Firstly, a comprehensive indicator system for co-evaluating the level of agricultural economy, resource, environment, ecology, technology and rural society is presented based on a holistic understanding of agricultural sustainability. Then, the entropy-based TOPSIS model, grey prediction theory and genetic algorithm are combined to build a synthesis method for evaluating and predicting agricultural sustainability and detecting its regional heterogeneity. Furthermore, an empirical study at a provincial scale is conducted by collecting panel data from 2003 to 2017. The result shows that regional agricultural sustainability in China will continue to improve, with different rates in the different provinces from 2020 to 2030. And the regional heterogeneity of agricultural sustainability will increase significantly.

In recent years, molecular simulations have received extensive attention in the study of reservoir fluid and rock properties, interactions, and related phenomena at the atomistic scale. For example, in molecular dynamics simulation, interesting properties are taken out of the time evolution analysis of atomic positions and velocities by numerical solution of Newtonian equations for all atomic motion in the system. These technologies assists conducting “computer experiments” that might instead of be impossible, very costly, or even extremely perilous to carry out. Whether it is from the primary oil recovery to the tertiary oil recovery or from laboratory experiment to field test, it is difficult to clarify the oil displacement flow mechanism of underground reservoirs. Computer molecular simulation reveals the seepage mechanism of a certain oil displacement at the microscopic scale, and enriches the specific oil displacement flow theory system. And the molecular design and effect prediction of a certain oil-displacing agent were studied, and its role in the reservoir was simulated, and the most suitable oil-displacing agent and the best molecular structure of the most suitable oil-displacing agent were obtained. To give a theoretical basic for the development of oilfield flooding technology and enhanced oil/gas recovery. This paper presents an overview of molecular simulation techniques and its applications to explore enhanced oil/gas recovery engineering research, which will provide useful instructions for characterizing the reservoir fluid and rock and their behaviors in various oil-gas reserves, and it greatly contribute to perform optimal operation and better design of production plants.

A swivel cable-stayed bridge over the existing railway is a span across the existing railway. The recommended scheme for the main bridge is (128 + 388 + 128) m steel mixed composite beam swivel diagonal pull bridge with span. The cables of the diagonal pull bridge are arranged according to the fanshaped central double cable plane, taking into account the mechanical performance and aesthetics. The bridge structure adopts semi floating system. The concrete swivel diagonal pull bridge is adopted in the comparison scheme. The design of the bridge is three spans and (138 + 268 + 138) m prestressed concrete box girder is adopted. The cables are arranged according to the central double cable plane, and the bridge composition adopts the consolidation system. Considering the needs of bridge operation and maintenance in the later stage of the bridge, when the dead weight of concrete diagonal pull bridge is within the ideal range, the concrete swivel diagonal pull bridge can be preferred. In order to calculate the dead weight of the selected bridge, the author uses the finite element software to model the whole bridge and calculate the weight of the bridge. The results show that the dead weight of the concrete swivel diagonal pull bridge is too large, which has exceeded the maximum bearing capacity of the existing spherical hinge. In order to continue to use the concrete swivel diagonal pull bridge scheme, it is necessary to optimize the design of the concrete swivel diagonal pull bridge scheme.

In order to study the influence of prestress on cantilever deflection and construction linear control of continuous rigid frame bridge in construction stage, this paper introduces the significance of continuous rigid frame bridge’s linear control, the calculation principle and deflection influence analysis of vertical formwork elevation in cantilever construction. According to a specific continuous rigid frame bridge, this paper use the finite element software to simulate and calculate the deflection of prestress to the cantilever construction of continuous rigid frame bridge. The influence of friction coefficient between prestressed steel bundle and bellows and prestress loss on cantilever deflection and construction line control of continuous rigid frame bridge is also analyzed, furtherly brings out the solution to deal with the problems due to the change of prestress.

Nowadays, high-order data needs to be processed quickly and accurately by various algorithms in distribution networks. It is difficult to ensure the accuracy of calculation both in low-order and high-order cases, due to the theoretical limitations of traditional high-order derivation methods. Aimed to improve the calculation accuracy, a new high-order derivative method based on the polynomial fitting is proposed in this paper. By analyzing the transient characteristics of voltage and current signals in the distribution network, the base fitting-function can be selected, and the coefficient of the base function can be obtained to fit the objective function by the least square method. The original discrete data will be replaced by new fitting-function for derivative operation, which not only ensures the anti-interference ability, but also overcomes the limitations of the traditional polynomial fitting method in high-order cases. The simulation results show that this method has high accuracy in high-order and low-order cases, and has good accuracy and anti-interference ability.

Digital economy follows three laws — the Metcalfe’s law. the Moore’s law. and the Davidow effect, which are practically in line with China’s poverty-alleviation initiative by developing cultural tourism. The Moore’s law, however, is paradoxical in given contexts, and thus, we proposed the “reverse-Moore’s law” to analyze the current cultural tourism-based poverty-alleviation policies. The features of digital economy can be employed to support the cultural tourism-based poverty-alleviation work: the development trend of digital economy also coincides with China’s cultural tourism-based poverty alleviation initiatives. With the poverty-alleviation work at Chishui City in Guizhou Province as the study case, this paper made an analysis from the perspective of digital economy to confirm the practical and surreal significance of applying digital economy to China’s poverty alleviation endeavors.

Chromium is one of main pollution in sea water, and the establishment of detecting kit is the research hot topic. In this study, immunized mice were obtained by immunogen Cr3+-EDTA-BSA, and hybridoma strains that secrete Cr3+-EDTA monoclonal antibody were selected. Cr3+-EDTA mAb were prepared with in vivo method. Then, Cr-kit for measurement of chromium was developed, and its application was executed in sea water and seafood. Two hybridoma strains of A321 and A424 were screened. The Cr-kit standard curve of the linear range was 1.0—512 μg/L, and limit of detection was 1.0 μg/L. The average recovery rates Cr spiked in samples of sea water, clam and shrimp were 102.62%, 94.69% and 96.29%, which were accordance with the results of ICP-AES. Totally, Cr-kit was successfully developed and behaved broad application potential in sea water and seafood.

Effectively improving and enhancing the data quality of colleges and universities is the most fundamental goal of university data governance. In this paper, first of all, the causes of data quality problems in colleges and universities are analyzed, and then the general idea of improving data quality is put forward, in which introduces how to identify data quality problems, how to solve data quality problems through technical and business means and how to make the data quality management of colleges and universities form a long-term mechanism through the construction of the system.

Authigenic chlorite, which is frequently found in sandstone, has a controlling effect on the reservoirs in which tight oil is adsorbed during hydrocarbon filling. In this study, the content, occurrence state, timing, mechanism and influence of authigenic chlorite on the micro-occurrence states of tight oil were studied using Thin Section (TS), Fluorescent Thin Section (FTS), X-Ray Diffraction (XRD), Field Emission-Scanning Electron Microscopy (FE-SEM), Environmental Scanning Electron Microscopy (ESEM), and Energy Dispersive Spectroscopy (EDS). The results indicate: (1) a spatial coupling between chlorite development, a brackish water delta front facies depositional environment, and biotite-rich arkosic sandstone. (2) Authigenic chlorite can be divided into three types: grain-coating chlorite, pore-lining chlorite, and rosette chlorite. Chlorite forms after early compaction but before other diagenetic phases, and grows via precipitation from pore waters that contain products released during the dissolution of volcanic rock fragments and biotites. Porewater is also pressure-released from feldspars and mudstone. (3) The micro-occurrence states of tight oil can be divided into five types: emulsion form, cluster form, throat form, thin-film form, and the isolated or agglomerated particle form. (4) During hydrocarbon filling, tight oil mainly occurs on the surface of grain-coating and pore-lining chlorite in the form of a thin film, the granular or agglomerated forms are mainly enriched within the intercrystalline pores within the authigenic chlorite, and the cluster forms are mainly enriched in dissolution pores. Isolated or agglomerated particles of tight oil primarily occur in the intercrystalline pores of the rosette chlorite. (5) The specific surface area and the authigenic chlorite’s adsorption potential of authigenic chlorite control the micro-occurrence of tight oil on the surface of the chlorite and in intercrystalline pores. The adsorption capacity of chlorite lies in the following order: pore-lining chlorite intercrystalline pores > rosette chlorite > chlorite in feldspar dissolution pores > pore-lining chlorite surface > grain-coating chlorite intercrystalline pores > grain-coating chlorite surface.

The safety evaluation of the aqueduct in many years of operation is often performed to determine the structural operational behaviour so as to provide a scientific basis for further reinforcement or reconstruction. The missing of the original design data due to the long construction period provides great challenging in the structural safety evaluation of the aqueduct. Taking a hyperbolic arch aqueduct in China as an example, we first rebuilt the aqueduct model using the three-dimensional (3D) point cloud from the three-dimensional laser scanning technology. Coupled with the on-site safety inspection, the 3D finite element analysis was then performed to learn the stress performance of the aqueduct body and its supporting structures, so as to achieve the purpose of safety evaluation of aqueduct structure in a whole.

Although Chinese instant tea powder production ranks first in the world, instant dark tea powder was rare in the market. Zhaoliqiao, Changshengchuan and Yangloudong Qingzhuan tea were used to optimize the technology process of high fragrance cold solubility instant powder while absorbance value was taken as detection index by single factor experiments combined with orthogonal experiments, which could provide a beneficial reference for deep utilization of Hubei Qingzhuan tea. The data showed the particle size of tea, tea-water ratio and extracting temperature significantly affected the extraction efficiency while extraction time did little. The extraction efficiency was the highest when using 120-mesh dark tea, extracting with 1:40 tea-water ratio, and extracting temperature of 100℃.

The main work of this paper is to establish an electric vehicle(EV) load forecasting model based on road network traffic distribution for urban and inter-city transportation networks. This paper established a road network model considering the traffic impedance for the EV load forecasting of the urban fast charging network, and studied the prediction method of the time-space distribution of EV charging demand in the fast charging mode .Based on the expressway, the method for predicting the time-space distribution of EV load in the inter-city fast charging network is studied, and a time-space distribution load forecasting model is established. Based on the time-space distribution of traffic flow, combined with EV charging characteristics and travel routes, load simulation is performed. By constructing a prediction method for the time-space distribution of EV charging demand in the fast charging mode, it provides theoretical and methodological support for the research of time-sharing and segmented metering and charging strategies for EV fast charging stations,, and provides an important reference for the development of EV charging facilities operating cost benefits, economic performance indicators and calculation models under fast charging mode, which are of great significance to promote the popularization and application of EV fast charging modes.

Concrete sandwich panel is a kind of building element with the characteristics of light weight, high strength, suitability for standardized production, meanwhile it has the multi-function of heat preservation and sound insulation which can be used not only as enclosure components, but also as structural components for multi-story residential buildings. A novel sandwich wall system has been presented in this work with an innovative design concept. Compared with traditional steel wire sandwich panel, this sandwich panel wall system has unique features such as prefabricated steel system, core column with spiral stirrup, foamed concrete as insulation layer. This wall system also meets the national policy requirements in energy-saving and has potential application and development prospects. In this paper, Finite element method is used to simulate and analyze the seismic performance of this new sandwich wall panel. The results show that the panel with 3D steel wire has greater stiffness and better earthquake resistance than panel with planar steel wire mesh.

Based on the principle of high frequency radio propagation, the signal reception mechanism of sky wave communication over oceans is investigated. Due to long distance signal transmission, the energy loss is inevitable, especially in the space and on the sea surface. Firstly, we establish the space propagation loss model by the ionospheric absorption, the free space propagation characteristics and other extra loss. Referring to the reflection principle of smooth ground and the Kirchhoff approximation, the energy loss models of the calm sea surface and the turbulent sea surface are obtained respectively. Then, through combining the space propagation loss model and the sea surface propagation loss models, we give out a formula of receiving point field strength. According to the signal to noise ratio, we summarize a complete and concise sky wave maritime communication calculation process, through which multi hops number of the receivable sky wave signal can be calculated accurately. The experimental results show the effectiveness.

River networks are basic parameters in river studies and river management. Due to scale effect, most river networks are lack of certainty. We selected three leafy rivers from different climatic zone with an approximately proportional relation in basin area (1: 4.1: 19.9) to dig the scale effect and possible similarity. The result shows that the resolutions of DEM and drainage area threshold are two key parameters to extract river network features from DEM. The river lengths and densities of all extracted optimal river networks under the 6km2 threshold values decrease with the spatial resolution. Based on 15 optimal river networks, the length ratio is similar to the area ratio, the density ratio is same (1: 1: 1), and the stream frequency ratio is near to 1: 1: 1. Bifurcation ratio values of all basins are closer to the average (4.75). These characteristics may imply that there is the similarity among rivers.

Financial time series is always one of the focus of financial market analysis and research. In recent years, with the rapid development of artificial intelligence, machine learning and financial market are more and more closely linked. Artificial neural network is usually used to analyze and predict financial time series. Based on deep learning, six layer long short-term memory neural networks were constructed. Eight long short-term memory neural networks were combined with Bagging method in ensemble learning and predicting model of neural networks ensemble learning was used in Chinese Stock Market. The experiment tested Shanghai Composite Index, Shenzhen Composite Index, Shanghai Stock Exchange 50 Index, Shanghai-Shenzhen 300 Index, Medium and Small Plate Index and Gem Index during the period from January 4, 2012 to December 29, 2017. For long short-term memory neural network ensemble learning model, its accuracy is 58.5%, precision is 58.33%, recall is 73.5%, F1 value is 64.5%, and AUC value is 57.67%, which are better than those of multilayer long short-term memory neural network model and reflect a good prediction outcome.

Stereo matching is one of the significant problems in the study of the computer vision. By getting the distance information through pixels, it is possible to reproduce a three-dimensional stereo. In this paper, the edges are the primitives for matching, the grey values of the edges and the magnitude and direction of the edge gradient were figured out as the properties of the edge feature points, according to the constraints for stereo matching, the energy function was built for finding the route minimizing by election campaign optimization algorithm during the process of stereo matching was applied to this problem the energy function. Experiment results show that this algorithm is more stable and it can get the matching result with better accuracy.

This paper introduces a design scheme of the residual current electrical fire monitoring detector performance test system based on virtual instrument technology. In order to test different current specifications monitor detector compatiblly,the system combines virtual instrument technology and computer control technology to improve the accuracy of output current of the current generator with electric voltage compensation technology and the way of closed-loop control ,and designs two sets of different size and the same type of pneumatic fixture to solve the connection of different specifications monitoring detector, software design adopts layered structure and the method based on configuration files, to better satisfy all kinds of test requirements for different products. Practical application shows that the system has the testing results of accurate, high efficiency and convenient operation.

In order to solve the communication problems when the mobile energy efficiency and energy-saving assessment system is applied to energy monitoring, the authors introduced two schemes about building wireless network which is introduced based on the demand of the mobile energy efficiency test and energy-saving assessment system. These two schemes are based on WDS (Wireless Distribution System), WSN (Wireless Sensor Network), they effectively solved the problem that signals could not be transmitted through the net when the mobile energy efficiency test and energy-saving assessment system is used to monitor the monitoring points which are located underground or in an extensive area.