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The purpose of this study is to solve the problem: in the warehouse temperature and humidity monitoring, due to the wide area and large number of warehouses, a large number of monitoring systems and equipment are arranged, which need to reduce investment and maintenance costs. Considering the same geographical environment, select 1 or 2 typical warehouses to represent the temperature and humidity of this region, so as to reduce the investment of monitoring equipment. We experimented with two regions separately, with 5 warehouses in each region. Temperature and humidity were collected for a period of time, and cluster analysis was carried out based on their maximum value, average value or comprehensive statistics of the two regions. The results show: (1) When clustering according to the maximum temperature and humidity, there are 2 types of significant differences warehouses in the same geographical environment. (2) When clustering according to the mean value of temperature and humidity, there are 2 or 3 types of significant differences warehouses in the same geographical environment, and the clustering result is different from that of clustering according to the maximum value. (3) When clustering according to the maximum value and average value of temperature and humidity, there is no significant difference warehouses in the same geographical environment, which can be classified as the same warehouse. No matter considering the maximum value, average value or the combination of the two statistics, the typical warehouse can be selected to represent the same geographical environment, so as to reduce the monitoring equipment investment and storage management workload.

This paper takes Liuzhou City as the research object to empirically test the short-term and longterm dynamic relationship between digital economy and urban carrying capacity. The research finds that: (1) Digital economy has a significant role in improving urban carrying capacity, but it presents a certain degree of instability. (2) The digital economy is characterized by centrifugal force

As people pay more and more attention to the environmental noise problem of substations, it is an important environmental protection work to carry out noise control of over-subjected substation. According to the lack of strict scientific argumentation, poor engineering control effect and high project cost, the paper proposes an accurate control model for outdoor substation noise. Taking the actual substation as an example, with the development of the substation environmental noise analysis system software SENCS, through six steps of data collection, model verification, pre-treatment analysis, optimization of governance plan and analysis of management effects, it is proposed the model of precise control of outdoor substation, which can play an important guiding role in outdoor substation noise control and new substation planning and design..

Asphalt profile control is an effective method, which can further improve oil recovery of reservoir polymer flooded, it has a lot of advantages including high strength profile control, seal strata formation efficiency, low cost and no pollution, but there has not a perfect evaluation system for its development mode. The effect of different concentration, injection rate, radius of profile control, the timing of profile and segment combination way on the oil displacement effect of the asphalt profile control were researched using numerical simulation method on actual typical well area in Daqing oilfield, and the mechanism of asphalt profile control was studied in detail. According to the results of laboratory test, the largest Enhanced Oil Recovery (EOR) of asphalt was obtained at injection concentration 4000 mg/L, and the best combination was “high–low–high” concentration slug mode. According to the results of numerical simulation, the best concentration, injection rate, radius of profile control and injection timing were 4000 mg/L, 0.15 PV/a (Pore Volume [PV], m3), 1/2 of well spacing and 96% water cut in single slug of asphalt injection system, when the injection condition was multiple slug, the “high–low–high” slug combination mode was the best injection mode. These results could provide effective development basis for asphalt profile control after polymer flooding in thick oil layers.

The heating methods currently used at oil delivery sites and transfer stations on North China Oilfield include electric bar heating, fuel oil heating, gas heating, etc. The traditional heating methods have adverse effect on energy conservation and environmental protection. They have low energy efficiency of heating and produces great pollution to the environment. The air source heat pump technology uses the heat in the air as the low-temperature heat source and transforms it to the high-temperature hot water, which will later serve as a heat tracing for crude oil gathering and transportation. No combustion effluent is produced in operation and the energy-saving effect is outstanding with high social-benefit.

During the Selective laser melting process, the accumulation of the residual stress caused by the excessive temperature gradients and the rapid solidification is the main factor causing deformation; and the wetting quality of the meltpool also has an impact. How to control the deformation is the key problem to improve the quality of the parts. In this paper, the thin-wall specimens are divided into four distinct conditions, analyzing the meltpool date collected by the melting pool monitoring system and the simulation of temperature field, the relationship between the process parameters and the deformation under the same energy density is discussed. The results show that the temperature, the width and the intensity of the meltpool increase with the increasing of the laser power and the scanning speed, but the temperature gradients and the rate of the solidification of the meltpool are on the contrary, resulting in the decrease of the residual stress and the deformation of the part, which is help to improve the quality of the part.

In this paper, a blended-wing-body lifting vehicle is designed, with the cross section described by Class/Shape transformation method (CST), the outline controlled by an exponential function, and tail regulated by B-spline curve. Rapid estimation procedures of aerodynamic based on plane method and of radar cross section (RCS) based on physical optics are developed and validated. A frame of integrated design and analysis of aerodynamic and stealth characteristics is constructed and applied to parameter sensitivity analysis. The results show that the parameters that affect the aerodynamic differ from those of RCS, which means the vehicle could be good at both aerodynamic and stealth, and the study followed should be focused on it.

We demonstrate the novel design of an electrostatic micro-actuator based on monolithic three-dimensional (3D) shapes fabricated by non-ablative femtosecond laser exposure combined with chemical etching. Further, we present a single-scan stacking approach exploited in the fabrication of the 3D actuator to create crack-free, highcontrast, high fidelity and integrated micro-structures. Influential parameters: energy per pulse, polarization, scanning spacing and stacking directionwere systematically studied to predict and control the etching rate of 3D planes.Finally, we report the characterization of the actuator and its potential application in optomechanics to show a complete scenario of femtosecond laser machined integrated 3D micro-systems incorporating multiple functionalities.

The application of biological organic fertilizer is one of the important measures to regulate the quality of tea. The application of organic fertilizer is helpful to increase the high quality of tea and regulate the soil physical and chemical properties and improve the soil environment. Then, the effects of different biological organic fertilizers on the growth quality of tea and the soil environment of tea garden were studied. The test results show that compared with the CK control group, T2 fertilization treatment is the most prominent in improving the polyphenols and caffeine content; meanwhile, T 6 fertilization treatment significantly increases the content of water extract and free amino acids of tea, which can effectively improve the composition of tea and improve the soil environment of tea garden. The application of six different organic fertilizers and different application amounts of the same organic fertilizer had significant differences on the content of tea water extract, tea polyphenols, free amino acids and caffeine.

With the development of Industry 4.0, in order to meet the needs of intelligent fault diagnosis of rotating machinery in the industrial field, this paper developed a fault diagnosis system for rotating machinery based on deep learning and wavelet transform methods. The system is based on the Python language and mainly combines the PyQt graphical interface framework and the TensorFlow machine learning framework to complete the training requirements for historical or online fault data, and perform online monitoring and diagnosis of equipment operating conditions. The diagnostic accuracy of the system test results is more than 95%, the software interface is friendly, the algorithm generalization ability is good, and the reliability is strong. It provides guidance for the diagnosis of rotating machinery.

With the improvement of information level, the information attack will cross the boundary of power grid information space and cause the disturbance of power grid physical system, which will form a cross-space chain fault and affect the safe operation of power grid. Based on this, this paper proposes a distribution network node risk assessment method based on information physical fusion. Firstly, the overall structure of the distribution network and the information physical coupling characteristics of the information physical fusion are studied. Then, the cross-space chain failure scenario of distribution network with information physical fusion is analyzed. Based on this, the risk assessment method is proposed. Finally, the effectiveness of the method is verified by a numerical example.

The double development of urbanization and motorization has made the traffic demand of our country grow rapidly and diversified. the improvement of urban traffic has become an important condition for the sustainable development of the city. Based on the analytic hierarchy process (AHP), this paper establishes the evaluation index system of urban traffic improvement by comparing the importance of indexing by experts. It is found that improvement of road network, optimization of public traffic and improvement of intersection are the most important in urban traffic improvement. the intersection of the most important level of service. By using qualitative and quantitative methods, the Likert scale was used to classify the results and the four-quadrant method was used to analyze the urban traffic improvement evaluation index system.

The high integration of cyber and physics is the development trend of intelligent distribution network in the future, but the cyber system not only supports the stable operation of the physical system, also brings some security risks to the cyber physical system of distribution network. Aiming at the requirements of real-time, accuracy, efficiency and other characteristics of distribution network monitoring, this paper proposes an early warning method of distribution network cyber physical system based on Hidden Markov model. Firstly, the online monitoring and early warning system architecture of distribution network information physical system is proposed, and then the early warning method of distribution network cyber physical system based on Hidden Markov model is established. Finally, an example is given to verify that the proposed strategy can accurately and efficiently early warn the fault.

As an important urban lake in Fuling District, Chongqing City, there is water blooms in Tonggu Lake, which affect the ecological environment. This study analyzed and studied the external and internal status of water pollution through site survey, water quality testing and analysis, and laboratory data analysis, and diagnosed the water environment of Tonggu Lake, which is helpful for providing strong data support for the follow-up solution to the problem of water bloom in Tonggu Lake.

Taking the wind turbine tower as the research object, based on the finite element software, a simplified beam-shell hybrid element model was first established; through the simulation, the phase difference between the loose position and the unloose position was compared to verify the feasibility of the phase difference detection method; Secondly, the influence of the number of loose bolts, the position of loosening, and the magnitude of the wind force on the phase of the flange bolt connection structure and the response characteristics of the system are analyzed. The research results show that the number of loose bolts, the position of loosening, and the magnitude of the wind have certain effects on the phase difference and response characteristics of the flange. With the increase in the number of loose bolts, the connection stiffness of the bolt connection continues to decrease. The linear characteristic is enhanced; the closer the loosening is to the excitation force loading position, the greater the detected phase difference; as the wind increases, the phase of the upper flange of the tower changes, and the phase of the lower flange remains unchanged, and the wind is on the flange The disc connection strength has little effect.

A self-designed new welding robot to be employed in the intersected weld of large pressure pipes is introduced in this paper. The welding robot can effectively serve as a substitute for a worker who would otherwise face a high labor intensity. The pose model of the welding tool is established to ensure that the welding tool maintains a good pose to make the molten pool run smoothly. The kinematics model of welding robot is established by Denavit-Hartenberg method, and the trajectory of welding tool is planned and determined. The designed of control system is communicated through PLC and touch screen, based on flexible modular mechanism, the welding tool pose can be adjusted according to the pressure vessel specification and the size of welding seam to ensure the welding quality of welding seam. Finally, the test unit for the designed robot system is set up, and experiments demonstrate that this welding robot could meet the intersected welding requirements of a large pressure vessels environment.

Apparent discharge quantity is usually recognized as judgement standard for severity of partial discharge in the field of electrical equipment insulation diagnosis. In recent years, the ultra-high-frequency (UHF) method has been widely used due to its unique advantages on on-line monitoring and positioning, but the relationship between UHF partial discharge signals and discharge quantity is still a difficult problem of UHF method. In order to research relationship between UHF partial discharge signals and discharge quantity in GIS, a large number of experiments, based on four kinds of typical insulation defects in the GIS, are carried out. Degree of correlation, between parameters including UHF energy, quadratic integral, peak voltage, peak-to-peak value, wave area and discharge quantity, the square of discharge quantity, is studied based on coefficient of determination. The experimental results show there is linear relation between UHF signal energy and the square of discharge quantity with high related degree.

A new kind of biocompatible probe (PEG-TPEFE) with aggregation-induced emission (AIE) characteristic was reported, which was synthesized from fluorene, tetraphenylethylene (TPE) and polyethylene glycol monomethyle ether 1000 (PEG1000). PEGTPEFE can aggregate into nanosphere and emit strong blue fluorescence in aqueous media. Cytotoxicity assay reveals low cytotoxicity and excellent biocompatibility of this nanoprobe. This nanoprobe was internalized and accumulated by live cells and shown high photostability.