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Over the last few years, existing and emerging Information and Communication Technologies (ICT) and artificial intelligence have been changing the way that factories conduct their manufacturing activities. Operation system of smart factories has been of great interest to researchers in recent years. However, the research concerning operations for the smart factory is still at the nascent stage. To address this need, we conduct a citation and co-citation analysis on smart factory operation system research published in the 11-year period from 2010-2020. A total of 351 papers were selected from Web of Science database. In the citation analysis, we depend on the degree centrality and betweenness centrality to identify 36 important papers. In addition, our main path analysis reveals the role of ICT in facilitating fast development of operation in smart factory. In the co-citation analysis, we identify four major research themes: resource reconfiguration, predictive production planning model, collaborative scheduling mechanism and technology basis of logistics. This is among the first studies to examine the knowledge structure of smart factory operations research by using evidence-based analysis methods. Recommendations for the future research directions have suggested based on our analysis.

This paper presents a new method, called data fitting method based on numerical results, to calculate the contact deformation between logarithmical crowned roller and raceway of rolling bearings. First, the contact deformations between logarithmically crowned roller and raceway are analyzed and numerically calculated according to influence coefficient method, and then a fitting formula based on the calculated contact deformations is obtained by means of multiple linear regression method. The formula includes the dimensions and logarithmic crowned parameters of bearing together with the load parameter, and can be used for fast calculation of contact deformation between logarithmical crowned roller and raceway in low and medium load conditions, so that the formula is suitable to efficiently analyze the dynamics characteristics of arbitrary logarithmic crowned rolling bearing.

Distance is usually obtained by ultrasonic wave. This research breaks the rules. Here the information of distance is got by visual range, which has been one of popular fields for many years. In this paper, the advance alarm system uses image processing technology to calculate distance between two vehicles. The system can accurately obtain distance and alarm effectively. The system is implemented by FPGA (Filed Program Gate Array), ARM and image sensor and calculate the distance through visual range technology. The simulation environment is built by HBE-SoC-EXPERT II development platform.

There are rich forestry resources, good climatic conditions, rainfall abundant, so lush plants, a good ecological environment in Dandong area, and rich mineral resources, mining economy vigorous development, but the development and utilization of resources is bound to adversely affect the ecological environment. This paper mainly Analysis on the influence of mining development on the ecological environment in Dandong area, and provides the decision basis for development of Castle Peak protection and the control work further.

The amplitude feature of those current eigenfrequencies resulting from bearing banded failure is merely focused even though it is very important for distinguishing bearing failure. This theme described the torque oscillation resulting from bearing banded failure based on periodic rectangular pulse model, deduced the modulation principle between rotor magnetomotive force and torque oscillation, presented the relation expression between various banded failure and the amplitude of different eigenfrequency. Finally, a series of simulation studies were conducted and results show that the proposed theory is valid.

The hydration ability of CaSO4 whiskers calcined under the condition of 475-500 °C for 10-60 min was researched by X-ray diffraction and scanning electron microscope. The optimal calcined CaSO4 whiskers were added into building gypsum and the bending strength of gypsum board was influenced by different dispersion methods. The results show that the whiskers calcined under 475 °C for 30 min begin to hydrate and the aspect ratio of whisker calcined under 500 °C and 525 °C has no changed for 1 h of hydration time. The bending strength value of gypsum board with ultrasonic dispersed whisker is lower than that of gypsum board with directly mixed whisker.

Smart jamming based on convolution modulation brings a great threat to active radar seeker. In order to counter the jamming, a method of orthogonal projection is designed. Firstly, both the mathematic models of linear frequency modulation (LFM) signal and convolution modulation smart jamming are made. Secondly, the anti-interference principle of orthogonal projection is analyzed, on the basis of which a reasonable filter is designed. Thirdly, simulations of signals respectively convolved with noise, triangle pulse sequence and rectangular pulse sequence are made, which verifies its good interference effects. The conclusion is that the method can effectively suppress the convolution modulation smart jamming.

Influence factors of sidewall stability contain mechanical factors and chemical factors. Among them, the chemical factor is the internal cause of the sidewall instability. Based on the collection of the influence factors of physical and chemical properties of the shale, we decided the main factors that influence the stability through the simple correlation analysis and applied a kind of quantum neural network based on the multilayer excitation function. We established the quantum neural network forecast model of shale physical and chemical properties that can effectively improve the network convergence speed and the accuracy of prediction. The quantum neural network prediction model analysis show that human factors interference of this method is small, and the system parameters needed less, wide application, the result is reliable, can effectively reflect the shale physical and chemical properties and fabric characteristics, to provide a reliable basis for preventing sidewall instability.

This paper researches law of reinforcement corrosion under chloride environment based on method the simulated accelerated test. Test the self-corrosion current density and electrode potential quantitative index of concrete reinforcement under chloride environment and establish quantitative model of corrosion time and reinforcement corrosion quantity by means of advanced linear polarization method and electrochemical testing method. Corroded reinforcement weight loss ratio under chloride environment is detected in physical way, combined with reinforcement corrosion layer microstructure and composition characteristics detected by scanning electron microscope. Both of the above deeply reveals corrosion mechanism and corrosion characteristics of the reinforcement. Corrosion rate theoretical model and statistical model have been revised. The research results prove that reinforcement corrosion rate has increased by an average of 4-5 times under chloride environment, weight loss ratio has increased by 15% compared with that under no-chloride environment, and due to chlorine’s effect, partial and uneven corrosion rust layer appears on surface of the reinforcement, which will be the direct cause of inducing accelerating corrosion of reinforcement at the later stage.

Email services are among the services most frequently utilized by smartphone users. However, setting up a smartphone email service is very frustrating for ordinary users as the process requires knowledge of complicated email server protocols and types of security. To eliminate the inconvenience, a method in which web mail setting information is preconfigured within an app has been applied to representative smartphone email accounts. However, it is not practical nor realistic to store all web mail setting information in the app; furthermore, private server setting information for schools, working areas and so on, has to be separately established by users. In this paper, we propose a system that removes these inconveniences faced when setting up smartphone email services. The proposed system automatically downloads setting information preconfigured on the email server for users.

In order to give full play to the airport for civil aviation security performance of the machinery and equipment, improve military efficiency as the goal, the whole life cycle of the product, a set of evaluation criteria and the guidelines by using mathematical methods to quantify, the establishment of a mechanicalinnovative design program evaluation preferred method and model.

Bridging technology is one of the most effective methods to prevent the solid and liquid phases into the well fluid from invading the reservoir. And selecting the bridging agent which best matches with the reservoir pore size is the key of the successful implementation of bridging technology. Because of the lack of precise and quantitative degree of the preferred theory of bridging agent in field applications, temporary blocking fractal theory has been introduced. The reservoir pore size distribution and the fractal geometric distribution characteristics of bridging agent have been described. At the same time, the temporary blocking fractal theory and the fractal dimension calculation have been introduced. Conduct temporary blocking experiments on the core of Jilin Oilfield by this theory and the results proved to be perfect. As a result, the correctness of temporary blocking fractal theory has been verified.

The starting energy dissipation of on-ramp system with open boundary condition is investigated by means of cellular automata simulations. We study the influence of the injection rate of on-ramp, the injection rate of main road and the removal rate of main road on the starting energy dissipation of each road. It is found that even though the injection rates neither of on-ramp nor main road have influence on the starting energy dissipation when critical values achieved, the removal rate of main road has a major impact on the starting energy dissipation of the system all along.

According to the mission to research an automatic send tea system. It's used to improve the actually problem of difficult take care of everyone that cause of large tea table and the large number of drink tea persons. In order to achieve automatic transmission tea, the auto-oriented mobile robot is designed to solve the above problems.

2500 meters below Baka block appears extremely thick coal seam and distributed long, unconsolidated and mixed up with carbonaceous mudstone between beds. The relieved stress after a new borehole is drilled will lead to the wellbore caving and peeling and finally form an approximate elliptic borehole, causing vicious accidents such as bit bouncing, bit freezing while tripping and even borehole discarding. The anti-sloughing capability of Amine Polymeric Alcohol (AP-1) was evaluated by tertiary recovery test and core immersing test, the formula of Amine Polymeric Alcohol drilling fluid system was also optimized. Indoor research shows that the drilling fluid is of strong inhibition and pollution resistance. Its plastic viscosity is 24 mPa•s, shear force is 11 Pa and permeability recovery value reached（81.9-89.6）%. The successful test in Ke 21 Ping 1 well indicates that Amine Polymeric Alcohol drilling fluid system with powerful inhibition can effectively solve the collapse of Jurassic coal seam and carbonaceous mudstone, present high lubricity and can improve the drilling speed effectively, meanwhile, it performances well in gaining reservoir protection, controlling drilling fluid rheological properties, enhancing pollution resistance and reducing the occurrence of complex accidents downhole. Thus it can provide reference for future drilling operation in sloughing formations.

Through simulation experiment of CO2 invading into drilling fluids that viscosity and yield point are increased dramatically and drilling fluids is in a bad rheology. The concentration of HCO3- and CO32- both are increased, the concentration of OH- and pH value of drilling fluid both are reduced. It does not meet the drilling requirement as the concentration of CO2 is too high, so we must eliminate it as soon aspossible. The glue soluting with KOH and CaO through some Lab experiments have optimized, which has a better performance for prevention and management of CO2 pollution.

The geological structure is very complex in Haita Basin, due to the difficult drilling, sidewall instability phenomena happened frequently during drilling process. And it has restricted the drilling speed and the development and exploration process seriously. According to the borehole collapse problems, physical and chemical properties experiment of mud shale had been operated, then we analyzed and predicted borehole stability of Haita Basin by experimental data, discussed the collapse mechanism in this area, and established corresponding countermeasures to prevent the collapse which has laid a good foundation for further research on key drilling technology and improving drilling rate in Haita Basin.

According to the strain energy equivalent, the resonant response equivalent static wind load of large span roof is derived. It solves the matter that should consider numerous structural response control objects on calculating equivalent static wind load for large span roofs, and establishes relationship with the structural strain energy introduced by fluctuant wind loads. Finally, the method is used to resonant equivalent static wind load analysis of 2008 Beijing Olympic Tennis Center Stadium roof structure. The results illustrate that the method proposed in this paper is effective and the precision is reliable.

Based on strain energy equivalent, the background response equivalent static wind load of large span roof is derived. It solves the matter that should consider numerous structural response control objects on calculating equivalent static wind load of large span roofs, and establishes relationship with the structural strain energy introduced by fluctuant wind loads. Finally, the method is used to background equivalent static wind load analysis of China National Stadium roof structure. The results illustrate that the method proposed in this paper is effective and the precision is reliable.

The design and development of a screw-drive in-pipe robot is presented. The robot is composed of power-driving module, walking orientation module, universal joints, and accessories. The application of automatic spring structure on the robot improves its adaptability. The robot is able to move smoothly in the vertical, inclined, or horizontal pipelines, or even when the cross-section of the pipe is not strictly circular. The calculation formulae of robot walking speed and motor driving torque are derived in this paper. According to the geometries at the bend and the motion constraints, the robot turning capacity and turning condition are also analyzed. The vertical, bend, and other tests are performed on the experimental prototype, demonstrating that the screw-drive in-pipe robot provides sufficient tractive forces and good maneuverability and adaptability.