Rolling Bearing Fault Diagnosis based on Residual Neural Network

<div class="Section0"><div>Because rolling bearings have been working in an environment with complex and variable working conditions and large noise interference for a long time, the bearing fault diagnosis method has a poor diagnostic effect under variable working conditions. To solve this problem, we propose a residual neural network based on the diagnosis method of rolling bearing fault. The proposed method takes rolling bearing time-domain signal data as input. Because bearing signals have strong time-varying properties, we construct a multi-scale residual block that can not only learn features at different levels, but also expand the width and depth of the residual neural network. We use the advantages of the dilated convolution to expand the receptive field, replace part of the ordinary convolution in the multi-scale residual block with the dilated convolution, and design a multi-scale hollow residual block. The advantage is that the method is made by expanding the receptive field. It has a strong feature learning ability and can learn better features under limited data. Finally, we add a Dropout layer to discard a certain proportion of neurons after the fully connected layer, which can effectively avoid the negative impact of overfitting, and use Case Western Reserve University bearing dataset, the simulation experiment, and the SVM + EMD + Hilbert envelope spectrum, BPNN + EMD + Hilbert envelope spectrum and Resnet three ways of comparative analysis, the results show that the method under the variable condition of the fault diagnosis of rolling bearing has higher diagnosis accuracy, stronger noise resistance, and generalization ability.</div><p> </p></div><p> </p>

Research on Construction Technology and Quality Control of Electromechanical Installation Engineering for Buildings

<p>Mechanical and electrical installation is a very important construction technology in construction engineering. From the perspective of the construction unit, whether the installation technology and procedure are scientific and reasonable will have a direct impact on the final quality of the project, and it is also closely related to the personal and property safety of the residents. Based on this, construction organizers should construct and perfect a standardized installation construction quality management system, clarify management regulations, and control key technical points, so as to comprehensively improve the quality of electromechanical installation projects and improve the project qualification rate. This article will describe the construction technology and quality control strategy of electromechanical installation engineering, aiming to lay a theoretical foundation for the improvement of engineering qualification rate and construction quality.</p>

Hydrogen Round Trip Efficiency

<p>The hydrogen economy is a glimpse into the future economic structure of energy. Hydrogen can be used as a power medium, and a typical way of using hydrogen is the round trip, defined as a process in which electricity becomes hydrogen and then returns to electricity form. The purpose of this paper is to briefly describe hydrogen round trip efficiency from production to releasing and find out the optimistic circumstances.</p>

Design of Traveling Wave Location Method for Transmission Line Fault Based on EMD-TEO

<p>With the rapid development of the social economy and the continuous extension of Internet technology, China’s power grid has entered the ranks of large-scale, high-voltage, and intelligent. The main purpose of the fault location of the transmission line is to eliminate hidden trouble and restore the fault line in time to ensure the safe and stable operation of the power system. With the advent of the smart grid, higher requirements are put forward for fault location accuracy, while the traditional wavelet transform and Hilbert-Huang transform have larger defects.</p><p>Therefore, this paper extensively analyses the generation and characteristics of fault traveling waves in transmission line fault, which proves that the traveling wave location method has higher location accuracy than the fault analysis method. Among them, the two-terminal traveling wave positioning method only uses the arrival time of the initial traveling wave, avoiding the principled defects and locating the dead zone of the single-terminal traveling wave positioning method, so the two-terminal traveling wave positioning method is generally used. The key of the two-terminal traveling wave location method is that it can accurately detect the arrival time of the initial traveling wave head. Although the Hilbert-Huang Transform (HHT) method can be used to detect the arrival time of the initial traveling wave head, the problem of inaccurate detection or failure of the wave head may arise when the instantaneous frequency of the IMF component decomposed by the Hilbert-Huang transform is used because of the mode aliasing in the empirical mode decomposition algorithm. Based on the above analysis, an empirical mode decomposition (EMD) combined with the Teager energy operator(TEO) is proposed for the traveling wave fault location of transmission lines. A large number of simulations prove that the EMD-TEO method in this paper can solve the problem of inaccuracy or failure of the HHT method using instantaneous frequency to detect the arrival time of wave head, and has higher fault location accuracy.</p>

Application of Sensor Technology in Electromechanical Automation System

<p>Sensor technology is a core of electromechanical automation system. Among them, sensor is also the most important content of high-tech electronic technology in China, but the application level of sensor technology in China is relatively backward. Although sensor technology is constantly updated and strengthened, there are still some problems in the application of sensor technology. In this paper, the problem of easy being interfered and high energy consumption has been explained, and some corresponding solutions have been discussed.</p><p> </p><p> </p>

The Strategy and Path of Finite Element Analysis in the Design of Auto Parts

<p align="justify">Under the background of helping to realize “made in China 2025”, it is the most challenging task to standardize the implementation of General Principles of Structural Finite Element Analysis for Mechanical Products (GB/T33582-2017). The current changes and progress of the automobile industry are promoting the development of innovation. Infrastructure design, reducing design risks and eliminating artificial subjective factors can shorten the design cycle of the goals to be achieved.</p>

Application of Electromechanical Installation Construction Technology in Practical Engineering

<p>Nowadays, with the continuous development of economy and society, the frequency of electromechanical installation projects in various industries is getting higher and higher. With the continuous improvement of mechanization level, the requirements for business personnel engaged in mechanical and electrical installation engineering are getting higher and higher. Electromechanical installation is a very important part in construction engineering. Only through continuous innovation, technical renewal and transformation, can the engineering function be effectively guaranteed and the economic benefit be increased. As urban construction enters the fast lane, people's requirements for the quality of life are gradually improved. The installation of construction electromechanical projects is the most prominent link in construction engineering, so construction units should pay attention to the installation of engineering electromechanical projects. The emphasis of engineering electromechanical installation is the control of installation quality and the innovation of installation technology. Based on the author's practical experience, this article first emphasizes the necessity of electromechanical installation, and then explains the relationship between construction engineering and electromechanical installation in combination with engineering practice, aiming at emphasizing the irreplaceable role of electromechanical installation in construction engineering.</p>

Research on Technical Management of Mechanical and Electrical Equipment Installation and Construction in Municipal Engineering

<p>In the construction of municipal engineering, attention should be paid to the installation of mechanical and electrical equipment and active application of integrated mechanical and electrical equipment. Based on this, this article briefly expounds the technical characteristics of installation and construction of mechanical and electrical equipment in municipal engineering, and puts forward the technical management points for it. In addition, it puts forward the application of mechanical and electrical integration, aiming at discussing the technical application points from the perspective of management, thus providing reference for engineering installation and construction.</p>

Application Analysis of Electrical Automation in Electromechanical Engineering

<p>With the progress of society and the development of science and technology, China's electrical automation technology has continuously overcome difficulties and made great progress. Electrical automation plays an important role in electromechanical engineering and is widely used. At present, remote control and management of the system are especially needed, which can be achieved by electrical automation. At the same time, electrical automation can also improve the working efficiency of equipment and effectively guarantee the safety of the project. This paper analyzes the application and development of electrical automation.</p>

Discussion on Technical Problems and Development Suggestions of Engineering Drilling Rig Automation

<p>As one of the important technologies in the mining industry, the drilling machine technology can improve the efficiency and quality of the mining industry. Compared with the traditional drilling machine technology, the drilling machine automation technology is obviously more reliable. Drilling automation technology can not only optimize the traditional mining efficiency, but also ensure the safety of people in the mining process. At present, the automatic drilling machine is the highest level of drilling technology in China. In the process of the automatic drilling machine, the downhole closed-loop technology can be used. This technology can completely separate from the human control and automatically complete the task only by transferring the information to the underground central computer.</p>