bluuebunny/crossref_metadata_2025 huggingface dataset:
Tensile Performances of Continuous Fiber Reinforced Thermoplastic Composites with holes processed by 3D Printing, Laser and Drilling
Authors: Chen Wei , Zhang Qiuju
Published: December 2022

The continuous fiber-reinforced thermoplastic composites (called CFRTPCs) have been used in transportation, aerospace, sports and leisure products because of their great green recyclability and mechanical performances. This study evaluated the 3D printing process for the rapid manufacturing of CFRTPCs. The effect of laser and drilling processes, the size and shape of holes on mechanical performances of CFRTPCs were evaluated individually and mutually. The results proved that the small holes and low fiber content helped improve the strain at break while the big holes and the high fiber content helped improve the ultimate tensile strength and elastic modulus. The ultimate tensile strength and elastic modulus of specimens with square or big holes were higher than those of samples with circle or small holes. The ultimate tensile strength and elastic modulus of specimens with circle holes by laser were higher than those of samples with circle holes by drilling while the trend of strain at break was opposite. The micro morphology of the tensile breakage was observed and analysed to study the failure mechanism. This work makes an important contribution to the design of 3D printed CFRTPCs parts with holes.
Effect of aging treatment on Microstructure and properties of Al-Cu-Mg alloy
Authors: Li Chun-ming , Lin Zi-yuan , Zhang Cheng-ji , Lai Wen-quan , Hu Ming-wei , Li Long-fei , Zhang Yang , Zuo Ling-li , Chen Lin
Published: December 2022

In order to meet the demand for high strength of Al alloy in aerospace, automobile, shipbuilding and other fields, the effects of aging treatment on the microstructure and properties of Al-4.5Cu-0.8Mg alloy were systematically studied. The results show that the main strengthening phase in the microstructure of the alloy after aging was θ’ And S’ phase, the comprehensive mechanical properties of single-stage aging after aging at 165 °C for 12h was better. In the alloy aged at 185 °C for 12 hours, the strengthening phase was coarsen obviously, the tensile strength and yield strength was decrease greatly and showed obvious over aging characteristics. The comprehensive mechanical properties of two-stage aging at 105 °C / 12h + 165 °C / 5h was the best. The tensile strength, yield strength, elongation and hardness are 543 MPa and 374 MPa, 17.5% and 170.6 HV respectively.
Solid-solution strengthening of Ti-Zr-Hf-Nb-Ta-Fe refractory high-entropy alloy
Authors: Liu Fuxin , Wang Benpeng , Wang Lu , Xue Yunfei
Published: December 2022

Ti-Zr-Hf-Nb-Ta system refractory high-entropy alloys (RHEAs) exhibits outstanding tensile ductility in room temperature. However, the moderate yield strength of them is insufficient. In this work, the Fe element with small atomic radius was added into a non-equiatomic Ti-Zr-Hf-Nb-Ta RHEA for furtherly improving the yield strength. As a result, the yield strength of modified RHEA is as high as ~970 MPa, while retains a considerable fracture train of ~17.5%. However, the Hf2Fe brittle precipitates were formed at grain boundary after aging treatment, leading to a further increment of yield strength but severe deterioration of ductility.
Mechanical properties of carburized 316L stainless steel lattice
Authors: Chen Ying , Yang Shaopeng , Chen Qi , Yang Ding , Liu Changmeng
Published: December 2022

The effect of low-pressure carburizing (LPC) on the mechanical properties of open cellular structures was studied by taking the 316L stainless steel body-centred cubic (BCC) lattice fabricated by selective laser melting (SLM) as an example. The mechanical properties of the corresponding solid material and the microstructure of the carburized layer were also analyzed. The results showed that the depth of the carburized layer was about 450μm, composed of three sub-layers. After carburized, the yield strength of the 316L solid was obviously decreased accompanied by the reduced elongation at break. The embrittlement was also reflected in the carburized lattice so that the fracture occurred and the energy absorption capacity weakened. Simultaneously, the compressive proof strength of the lattice was improved after low-pressure carburizing due to the toughness inherent in the structure.
Research on Self-collimation Full-scale Angle Measurement Method Based on Composite Biaxial and Combined Target
Authors: Li Kun , Cao Guohua , Ding Hongchang , Hou Han
Published: December 2022

In order to solve the problems such as the limited field of view of traditional self-collimation detection, the inability to achieve continuous detection of 0~360° full circumference and the existence of zero drift in self-collimation measurement. The positive and negative rotation of the inner and outer axes of the dual-axis turntable is used to realize high-precision continuous angle measurement with the autocollimator as the angle reference, and the combination of the compensation target and the fixed target is used to realize the closed-loop compensation of the drift of the autocollimator. The results show that: the repeatability error of the system is 0.05”, and the detection accuracy of the system reaches 1.64”. On the premise of ensuring the stability of the self-collimation angle reference, the self-collimation full-scale small angle measurement is realized.
The static analysis of reconfigurable wheel-track transformation mechanism
Authors: Yan Lihao , Xu Xiaojun , Tang Yuanjiang , Jiang Yue , Chen Guanpeng , Zhang Guoqing
Published: December 2022

The reconfigurable wheel-track transformation mechanism is characterized by short conversion time and excellent terrain adapability, appropriately resolving the contradiction between trafficability and mobility. Based on a new transmission scheme, this paper focuses on the mechanical properties of its transformation mechanism, so as to provide theoretical support for structure optimization. The mechanical model is established by analyzing the forces of key components during the process of transformation, after which stress and strain of them is analyzed through finite element analysis software, according to previous calculations from the model. The results show that parts with direct contact with ground bear more forces than others. Maximum stress of parts is within the limit strength of materials, but structure of weaker parts should be further improved to reduce stress concentration.
Transient Force-Magnetic Coupling Simulation Research on Pipeline Stress Concentration
Authors: Su Zhengda , Xin Jiaxing , Zhang Qingbao , Chen Jinzhong , Guo Yanbao
Published: December 2022

The stress concentration of oil and gas pipelines will produce corrosion cracks and axial fatigue cracks under the action of long-term and repeated internal pressure, and will rapidly expand under fluctuating internal pressure, resulting in serious pipeline accidents. In order to effectively detect the stress concentration of oil and gas pipelines, a stress concentration detection technology of unsaturated local magnetization pipeline is proposed. This paper introduces the theoretical basis of local pipeline stress concentration detection, establishes a two-dimensional finite element model of pipeline stress concentration transient force-magnetic coupling, and analyzes the influence of excitation source position, sensor lift-off value, and stress concentration value on the response signal. The simulation results show that the corresponding signal
B
x
of the stress concentration changes more obviously than
B
y
and the signal is regular, Bx
has a good two-stage linear positive correlation with the stress concentration value. The above research provides technical support for the development of pipeline on-line stress concentration detection probe.
Research on the film wrinkle in the transmission system with traction rollers
Authors: Lin Xichen , Liu Huihui
Published: December 2022

In this paper, a production line of film extraction and transmission with traction rollers is discussed. Wrinkles sometimes appear on the whole film in a few days after the production line starts up. The film and traction rollers system’s models are established. Impact factors and change laws of rollers characteristics are studied. Influence parameters such as friction coefficient, rotating speed, roller deflection and clearance are analysed to ensure the stability of the film transmission system.
Derivation of Relation between Angle of Attack and Effect of Leading Edge Erosion on Airfoils at the Tip of Wind Turbine Blades
Authors: Pan Mingyang
Published: December 2022

Leading-edge erosion of wind turbines is caused by particles in wind. Impacts at a high velocity damage the blades severely and lower the aerodynamic efficiency. The aim of this paper is to estimate the flow rate hitting on the leading edge of the airfoil NACA4412, which forms the tip of a wind turbine blade, with the geometry referred to NREL offshore 5-MW baseline wind turbine. The methodology is to first compute the coordinates of the points on the boundary of the airfoil that is defined to be the leading edge, then with trigonometry relationships of the airfoil, the length that is passed through by wind can be found. Finally, relating them together, a differential equation is established. It reveals how the angle of attack and flow rate through the leading edge are correlated. With graphs plotted, the equation states that changing the angle of attack from 6 to 7 has 6.2% less erosion while Cl/Cd is dropped by 4.6% only. Hence, for situations where leading edge erosion and aerodynamic efficiency are considered equally important, it is better to vary the angle of attack to 7 degrees rather than the optimal 6 degrees.
Study on Wear Mechanism of Bell-shaped cover of Vertical Scraper Centrifuge
Authors: Yang Jie
Published: December 2022

Based on the basic structure and working principle of vertical scraper discharge centrifuge and combined with the actual use, this paper puts forward the main influencing factors of bell-shaped cover wear, studies the wear characteristics of materials on bell-shaped cover, analyzes its wear mechanism, and determines the easily worn parts. Taking the bell-shaped bell-shaped cover of the LLL1200 vertical scraper discharge centrifuge as the research object, the speed and angle of materials eroding the bell-shaped cover at each position are calculated through the analysis of the movement track and force of solid materials in the centrifuge. The erosion and wear speed of materials on the outer end of the rib plate side is the maximum, 23.06 m/s, the speed on the inner wall of the coal retaining ring is slightly lower, 13.87 m/s, and the speed on the upper surface of the rib plate is the minimum, 0.53~ 0.69 m/s. In addition, two methods to prolong the service life of the bell-shaped cover are proposed. The industrial application shows that inlaying alumina wear-resistant ceramics on the bell-shaped cover is the most effective and simple method.
Vibration energy flow of main drive system of hot tandem mill
Authors: Wang Lidong , Yan Xiaoqiang , Wang Xiaoling
Published: December 2022

We analyzed the power flow of the vibration transmission of the F2 mill drive system coupled with complex beams using the substructure method. The system was divided into three cylindrical substructures, which were coupled to each other by three spring-dampers. The modal analysis of the substructures was conducted to describe their dynamic characteristics; subsequently, the substructure receiving function under free interface conditions was established. The dynamic characteristics of the transmission coupling system were calculated by synthesizing the force balance conditions and geometric coordination at the coupling interface. The input energy and transmission energy in the system were effectively evaluated. The effects of spring-damper stiffness change, excitation position, and loss factor on the transmission of vibration power flow were studied and verified by field experiments. This study provides an effective theoretical basis for vibration suppression measures for hot tandem rolling mills.
Failure analysis of the piston used in a pneumatic down the hole impactor
Authors: Pan Peng , Li Yongsheng , Chen Yunbo , Wang Jinnan , Zuo Lingli , Chen Rongrong , Zhang Baoyan
Published: December 2022

In this paper, the failure mechanism of the piston in the pneumatic down the hole (DTH) impactor has been studied. Failed piston microstructure has been analyzed using the light optical microscopy (OM) and scanning electron microscope (SEM). Impact toughness test and the Rockwell hardness test were conducted. Results showed the following: a) The carburizing layer of IQCT failed piston is mainly composed of acicular martensite and lower bainite after the carburizing-tempering-isothermal quenching-cryogenic treatment-tempering (IQCT), and there are collapses on the impact side and outer surface of the piston, mainly fatigue failure. b) IQT failed piston samples are subject to carburizing-tempering-isothermal quenching-tempering treatment (IQT). The carburized layer is mainly composed of high-carbon martensite, carbide and retained austenite. The transition layer is still composed of lower bainite and acicular martensite, but the volume fraction of lower bainite increases significantly and the core is mainly composed of lower bainite. It has the best impact toughness, up to 61.5 J/cm2, which is mainly fatigue failure. c) OQT failed piston sample is subject to carburizing-tempering-oil quenching-tempering (OQT). The carburized layer is mainly composed of acicular martensite, the transition layer is composed of acicular martensite (AM) and lath martensite (LM), and the core is mainly composed of LM. The impact toughness of the sample is the worst. Therefore, fatigue fracture failure is caused.
Two Methods of Matrix Factorization and Their Applications
Authors: Zhang Wantong
Published: December 2022

Many problems in real life are summed up as mathematical models. Linear equation set is a more common approach among all mathematical models. Given particular scenarios and conditions, linear equation sets can solve problems such as resource allocation. This paper mainly introduces two basic methods of matrix factorization, explains how to simplify the solving process of linear equations by using elimination method, and applies the model into a real-life problem.
Comparison of Statistical Estimators for Estimating the Orders of Markov Chains
Authors: Meng Jingxiang
Published: December 2022

High order discrete Markov chain is essential to analyze the dependency structure of data sets. To apply Markov chain correctly, even though the true order is an unknown parameter, statisticians have developed multiple order estimators. It is natural to identify the strongest order estimators under different parameter combinations. Aim for evaluating the performance of estimators, we study four of them in this paper: Akaike information criteria (AIC), Bayesian information criteria (BIC), Maximal fluctuation estimation method (PS), and approximate χ
2 − distribution method (Dk
). We simulated Cr
× C transition matrices to generate word-count-based Markov sequences with the most straightforward initial distribution. We found PS and Dk
give more accurate discrete Markov order estimation. Although AIC and BIC are commonly applied, their performances are not the most accurate. The accuracy declines approximately exponentially as the Markov model gets more complex, i.e. r ≥ 1 and C ≥ 3. AIC’s accuracy is higher when the Markov chain length is relatively small, but Dk
yields a slightly higher accuracy under the same setting. PS give a more reasonable estimation when Markov order is the variable, i.e. 1 ≥ r ≥ 3. Dk
gives more reasonable estimations when the length L and alphabet size C are variable, i.e. 150 ≥ L ≥ 800 and 3 ≥ C ≥ 5.
Development of Computational Chemistry and Application of Computational Methods
Authors: Ma Xiaoyue
Published: December 2022

This paper discussed the development of computational chemistry, some representative computational chemistry methods and some machine learning algorithms applied to computational chemistry. Computational chemistry has grown considerably since the 1920s and is rapidly becoming an important and emerging sub-discipline in the whole field of chemistry. In recent years, the introduction of machine learning algorithms such as support vector machines and deep learning has made computational chemistry processes more accurate and efficient. The application of computational chemistry in areas such as conformational prediction has brought about a revolutionary change in chemical research.
Possible Implementations of Oracles in Quantum Algorithms
Authors: Zhao Jiahao
Published: December 2022

Quantum computing is an inspiring technic on solving complicate problems, which shows the superiority over the classical computing. Contemporarily, the quantum-based algorithms were invented in many purposes on solving those problems. The thing is some of the algorithms were composed with oracles, which can be treated as a black box. It can be worked out/analyzed in theoretical mathematical expressions, but it can never fall in the ground without those actual implementations. Therefore, this paper will illustrate the idea and possible implementations on some quantum algorithm. Among various algorithms, this research will choose those relatively famous quantum algorithms, i.e., Deutsch-Jozsa Algorithm, Shor’s Algorithm, and Grover’s Algorithm. Different algorithms have the different intrinsic logics, which means there is no general description for all solution in this problem, but all of those can achieve the goal according to the same framework. Since those oracles are black boxes that can only be analyzed by its behavior with different cases, and then based on the behaviors and cases, and in IBM quantum platform, one can fill out the oracle by manipulate with different quantum operators. Lastly, the figures of some the possible implementation of those oracles with the three quantum algorithms will be shown in the IBM quantum platform, as well as the histograms of probability distributions that can justify the correctness of the implementations. These results shed light on guiding further exploration of the design and analysis on quantum algorithms.
An Overview of the ITER Project
Authors: Geng Shuaibo
Published: December 2022

ITER (initially the International Thermonuclear Experimental Reactor) is the most perspective project to achieve fusion energy. In this article, the origin of the ITER project, fundamental members and how the design of Tokamak provides the demand or suitable conditions for ITER to achieve its scientific or experimental goals will be discussed. In addition, the technological improvements in several different aspects and how it can function under different situations will be introduced. The principle of nuclear fusion and nuclear reactor and how the energy is created and conserved in the whole process will also be explained. This will lead to the significant problem that is considered the relationship between the ITER project and new energy resource form. The future prospects of this type of future energy resources and comparison with other present energy recourses will be discussed as well.
Analysis Concerning the Problem of the Optimal Delivery in Three Towns
Authors: Gong Yuxin , Xiang Jianxin , Yao Jiawei
Published: December 2022

The aim intimately pertinent to this research program is to use constructive mathematical notions to analyze how constructive real numbers and rational numbers are likely to have an influence on the outcomes involving economic problems. Researchers endeavor to find a computer program to determine the optimal location of a production plant and to find out that provided that the distances from the production plant to the sales location are rational numbers, then the problem is algorithmically solvable, though, if the distances are constructive real numbers, then the existence of the computer program that solves all such problems will not be possible.
Integer Solution for a Class of Indeterminate Equations
Authors: Zong Qi
Published: December 2022

The mathematical discipline of number theory has a long history. It originated in the ancient Greek period in natural mathematics and geometry. With the progress of science and technology, people began to recognize the importance of “number,” which led to the rapid development of number theory and gradually becoming an independent discipline. Indeterminate equations are one of the most important branches of number theory and have always received a lot of attention from the mathematical community. The problem of integer solutions of indeterminate equations was also called the Diophantus equation because of the profound study of these equations by Diophantus in the early third century. However, there is no unified method for solving the Diophantus equation today, so the investigation of its integer solution often needs to be combined with previous studies. This paper focuses on the application of Gaussian rings of integers and congruence theory to the study of integer solution problems for indeterminate equations of the form x^2+4^k=4y^n (k=1,2 n=3,5..). The study generalizes the understanding of the local distribution rules in specific situations, which helps to simplify the discussion of the classification of this category of problems and provides alternative ideas for subsequent more in-depth studies by others. This paper concludes that every such indeterminate equation can be discussed in x ≡ 1 (mod 2) and x ≡ 0 (mod 2). A template for discussion is provided for the first scenario, and only when 2k-1=n can there exist only an integer solution (x,y)=(±2^k,3) for the second scenario.
The Scope of Application of Letter Frequency Analysis in Substitution Cipher
Authors: Pan Yining
Published: December 2022

Since its inception, substitution ciphers have been a popular type of cipher, and over time, academics have studied them in an effort to discover patterns that will allow them to be broken. They created it because substitution ciphers are a reasonably simple type of cipher. Through a survey of the literature, this paper investigates the encryption and decryption of three sub-types of monoalphabetic ciphers: shift cipher, affine cipher, and random substitution cipher. Letter frequency analysis is the foundation of the primary decryption technique. After that, two sub-kinds of monoalphabetic ciphers, Hill cipher and Playfair cipher, which are resistant to this decryption method because the letters encrypted hardly keep the original frequency, will be introduced. The paper shows that statistical analysis of letter frequency is only useful for deciphering single-table substitution ciphers.
Applications of Advanced Mathematics in The Field of Economics
Authors: Sun Yibing
Published: December 2022

The application of mathematics permeates different fields, especially in the field of economics. The connection between economics and mathematics is indispensable. It can also be said that the problems and research in the economic field are inseparable from the support of mathematics. This paper explores the connection between advanced mathematics and economics and its application in economics through the literature review method. Through example studies, the paper finds that only by choosing appropriate mathematical methods for different economic problems can economic problems be solved effectively.
Different Algorithms to Solve a Rubik’s Cube
Authors: Chen Juntao
Published: December 2022

This essay introduces and compares four methods to solve a Rubik’s cube which are Korf’s algorithm, Thistlethwaite’s algorithm, Kociemba’s algorithm and machine learning method. Rubik’s cube is a rather complicated problem to solve, investigation on the algorithms to solve a Rubik’s cube can provide some valuable enlightenment which can be applied to other complex areas. Through comparing the efficiency of the four methods, this essay indicates that Korf’s algorithm is the most efficient algorithm to solve this problem, while Kociemba’s algorithm is the second. On the other hand, machine learning method will be the future prevalent algorithm to be investigated. Although it appears to be less efficient in solving this problem, it has more potential than the other three algorithms.
The Principles, Algorithms and State-of-Art Applications of Quantum Computing
Authors: Duan Hongyu
Published: December 2022

Contemporarily, quantum computing has become a popular topic, which is a new approach that is different from classic computing. To be specific, it can deal with information by using mathematical modeling that used to represent quantum mechanics, including superposition, interference, and entanglement. In quantum Computing, information is storage in ‘qubit’, whereas classic computer use bit to store information. This article aims to introduce the principles and some algorithms of quantum computing, and then discuss some up-to-date important development. There are two important algorithms are mentioned in this article, Grover’s algorithms and Shor’s algorithms. According to the analysis, Grover’s algorithms is potentially faster than classic algorithms. However, it requires millions of qubits to make it. Besides, Shor’s algorithms have challenged classic encryption (RSA encryption). Two quantum computer Google Sycamore and Jiuzhang are also mentioned here. The interesting thing is, for some specific question, Jiuzhang performed better than classic computers. Finally, it is found out that the quantum computing is generally slower that classic computer now, due to the restriction of qubit numbers. However, quantum computing still has an advantage in some specific question. These results shed light on guiding further exploration of quantum computer designing.
RETRACTED: Application of Convolutional Neural Network in Modern Technology Field and Improvement by Time-space Version
Authors: Hung Shengyu
Published: December 2022

Based on the basic principle of convolutional neural networks, this paper gradually introduces the development of convolutional neural networks and its related application fields. We also analyze and compare the iterations and developments of convolutional neural networks in three most commonly used areas: medical treatment, face recognition and transportation. A large number of articles have been written to understand the variations and differences of convolutional neural networks in these three areas, such as the use of different training methods or different structures, such as the time-space convolutional neural networks that will be mentioned in the article. And the last part is the summary.
Attention-based Dual-channel Deep Neural Network For Aero-engine RUL Prediction Under Time-varying Operating Conditions
Authors: Zhao Zijian , Zou Pengyuan
Published: December 2022

For complex systems such as aerospace, remaining useful life (RUL) prediction is a general technique that provides information for decision-making in predictive maintenance. In the industrial field, RUL prediction under time-varying operating conditions is a challenging task. In this paper, an attention-based dual-channel deep neural network is proposed to fuse the time-varying operating conditions, with both prediction channels using long short-term memory (LSTM) neural networks. First, the features are extracted by a one-dimensional convolutional neural network (CNN). The operating conditions and sensor data are put into the dual-channel LSTM neural networks separately for prediction. The obtained results are combined with the attention mechanism to assign weights and finally put into the fully connected network for linear mapping to get the final RUL prediction results. This study is based on the N-CMAPSS dataset published by NASA. Compared with traditional methods, this method demonstrates its superiority and effectiveness.
Research Progress of Atmospheric CO2Monitoring by Satellite Remote Sensing
Authors: Gao Ruiyang
Published: December 2022

Carbon peaking and carbon neutrality are gaining popularity in the international community. As a result, there is a growing demand for high-accuracy quantification of carbon sources and sinks. Global carbon dioxide (CO2) concentrations measured by satellite are essential evidence for accurate CO2 emissions estimation. And advances in infrared hyper-spectral technologies have enhanced satellite-derived CO2 estimation. This paper reviews the development of space-borne instruments, such as the infrared hypersoectral sounder and lidar, from the 1950s. The two types of infrared hyperspectral sounders, including sounders for observing atmospheric profiles, such as AIRS, IASI, CrIS, and HIRAS, and special instruments for observing atmospheric composition, such as GOSAT, OCO, GAS, and ACGS/TanSAT. The precision of total volume CO2 concentration products has improved. It therefore encourages satellite observation based researches into carbon sources and sinks, as well as emissions inventories. And rising of related publication is well corresponding to the launch of new instruments. And in the future, the rapid development of lidar observation will further improve accuracy of CO2 monitoring.
A Study of the Use of Euler Totient Function in RSA Cryptosystem and the Future of RSA Cryptosystem
Authors: Wang Shuodong
Published: December 2022

At the end of the last century, an innovative two-key cryptosystem called RSA was created due to booming demand for secure remote communication. The core for this encryption system is a mathematical function called the Euler totient function (Euler φ function), introduced by Leonhard Euler. This article will first deduce four theorems related to Euler φ function, and then illustrate the correctness of the RSA cryptosystem using Euler’s φ function. The study then starts with well-known RSA attacks such as the Coppersmith attack, assesses some of RSA’s vulnerabilities, and measures the impact of quantum technologies on RSA. Finally, this study provides projections and recommendations for the future development of RSA based on all evaluation studies completed during the entire research program.
Reframe the Field of Aerospace Engineering Via Machine Learning: Application and Comparison
Authors: Ni Zhehan
Published: December 2022

Machine learning (ML) shows its significant efficiency and excellent performance of computing while handling various complex issues in different areas since the term ‘Big Data’ emerged in the early 1990s. Big data analysis and ML that are effective at resolving various multi-objective as well as limited optimization issues that emerge in spacecraft design and manufacture, are positioned to benefit the aerospace industry. This research paper demonstrates a radical analysis of the use of ML in aerospace engineering. Spacecraft section focuses on anomaly detection, collision avoidance and attitude control. Artificial satellite part is categorized in satellite communication and default diagnosis while thermoacoustic instabilities detection and lunar landing are the main concentration on rockets. The vast application of machine learning in aerospace engineering certainly boosts the growth of the modern aerospace industry as each collected data contributes to a better trained system for attitude control, navigation and default diagnosis which significantly increase the success rate of future space exploration missions.
The Analysis of EEG after Mild Traumatic Brain Injury(mTBI) Using CWT and CNN
Authors: Ma Detao , Wang Chang Le , Zhang Lanxi , Zhou Xuanyi
Published: December 2022

Electroencephalography (EEG) is a bio-signal used in various approaches such as clinical diagnosis. The analysis aims to investigate the validity of EEG signal detection after mTBI which refers to mild traumatic brain injury. Although EEG does not directly present features that could be found within mTBI, by utilizing the processing method of CWT (Continuous Wavelet Transform) and CNN deep learning which will be mentioned, the resulted accuracy reached 91.29%. This study indicates that the proposed CWT-CNN method may have a potential usage in the identification, classification, and monitoring of mTBI patients.
How Machine Learning Applied in Covid-19 Prevention & Control
Authors: Fang Ruiqi , Guo Jiajun , Xian Bolong
Published: December 2022

Since the outbreak in the beginning of 2020, the COVID-19 pandemic has spread out to all around the world and brought severe lost to lots of aspects of the society. To prevent and control the epidemic situation, models based on machine learning have been widely applied in many medical domains. Despite the abundant researches and works, there are few academic reports make review on them. This study is aimed to fill this gap by providing an systematic review of the machine learning technology applied in dealing with covid-19, including clinical diagnosis, transmission prediction and drug and vaccine invention. This will provide advantage for further research into the application of machine learning in medical and public hygiene area and give instructions for medical workers related to epidemic prevention and control in the future.
Experiments of Mutual Information Maximization on Deep Infomax
Authors: Han Zihao , Lin Zichao
Published: December 2022

Image search and photo search at the current level of science and technology have become increasingly mature, and the underlying logic of these is the clustering of pictures. Mutual information(MI) is widely used in machine learning and deep learning, its value cannot be computed directly. Therefore, there are several methods to estimate MI, such as Deep VIB, MINE, and MoCo. Deep Infomax(DIM) technique is applied to maximize the MI based on Jensen-Shannon divergence. The paper derives the mathematical formula of Deep Infomax first. If two images have the maximum MI, it could be concluded that they are similar images. In the experiment, this technique is applied in clustering of datasets that are cifar10, celeba. In the experiment, the results of cifar10 and celeba are close to expectations and can be considered to have achieved good results. In cifar10, it clusters images of similar colors. In celeba, it clusters together faces of the same skin tone and even expressions. This paper and experiment could conclude that Deep Infomax is an effective way to cluster the images and maximize the mutual information.
The Research and Analysis of Different Face Recognition Algorithms
Authors: Xiang Wang
Published: December 2022

With the background of fast developing artificial intelligence and Internet technology, face recognition, one of the product technologies under the theory of machine learning, has become widely applied on safety tests, identity confirmation, public security photos, and access control system. Based on the trend of its development speed, this technology will have well developed circumstances and the field of application will expand. One of the most essential reasons why it has become so popular is that the algorithms used for face recognition are advanced. In this paper, the author mainly researches five algorithms to realize face recognition based on relevant literature. They are separately CNN, PCA, SVM, MTCNN, and Facenet. After comparison and analysis, it can be found that CNN is one of the most suitable algorithms to recognize human faces, and PCA and SVM have problems of calculating speed. The use of complex neural networks can intensify the accuracy of face recognition just like MTCNN and Facenet. If combining different algorithms together and using their advantages in face recognition in different steps, the prediction of the algorithms will be better.
Basic GAN Models and the Application In Medical Image Field
Authors: Li Kangning
Published: December 2022

Generative adversarial networks (GANs) have shown its prominent performance to the world and be exploited in many areas. For example, generating human face image, translating image between different domain, generating supplementary data for tasks which lacks training and labeled data. Specially, GANs also shows its potential in medical image analysis. It can tackle the problems in medical image analysis such as medical image translation, segmentation, reconstruction, detection and image classification. Being capable of generating images at amazing level of realisim, GANs gives the opportunity to resolve the problem that labeled data for those rare diseases cannot meet the need for medical field. In this paper, we give an overview of GANs and its application in medical image analysis. Defects and advantages of those GANs methods are also thoroughly reviewed. We also discuss its potential improvement in future. We review those most frequently methods published until now. And essential details about papers we discussed in this paper and access to that paper is attached at the endpage.
Comparison of Decision Tree, Random Forest and Linear Discriminant Analysis Models in Breast Cancer Prediction
Authors: Wang Rui
Published: December 2022

Breast cancer is one of the illnesses that has become a leading cause of female death worldwide, and early diagnosis of these diseases is a difficult and important undertaking. The intention of this paper is to design prediction models based on Decision Tree, Random Forest and Linear Discriminant Analysis respectively to forecast the breast cancer occurrence at an early stage. The design is focused on analyzing the minimum set of attributes from the clinical data set that have been chosen by experts, and then compare the performances of the models to find their advantages in each model. Breast Cancer Wisconsin Data Set is used in this paper to construct the expected prediction models. Classification accuracy which is determined by comparing real values with predicted values, and generalization ability which is reflected by Receiver Operating Characteristic curve, are used to gauge the performance of the models. The results confirm that the Random Forest model can achieve the highest accuracy to 99.4% and the best generalization ability. However, the Linear Discriminant Analysis model can keep better stability in prediction accuracy and has the fastest running speed.
A Study on the Development of the Rocking Structures in Past 20 Years
Authors: Xu Yutong
Published: December 2022

Pendulum structure refers to release the rotational freedom of the structure and the foundation, so that the structure and component can lift, swing with descending manner or rotate with fixed center under the action of external forces, so as to control the intraformational deformation distribution mode of the structure. Because the building structure is inevitably damaged to a certain extent under the action of strong earthquake, the purpose of “repairable” will be achieved if the damaged part and degree of the structure can be effectively controlled. In this case, Housner found out in the 1960s that the upward lifting of buildings could protect the structure itself, which became the initial discussion of modern pendulum shock absorption system. Currently, pendulum structures have developed into a variety of branches and damping forms. This article classifies and summarizes the new developments of pendulum structures in the past 20 years from three directions, namely pendulum walls, pendulum columns and pendulum frames. It gives its own views and prospects on the future development of pendulum structures.
Research on Drip Irrigation System Based on Self-Controlled System
Authors: Chen Ruimeng
Published: December 2022

With the increasing demand of efficient drip irrigation systems worldwide, there are many of them which contain feedback system to control drip speed based on factors like temperature, plant types and soil moisture. This paper is about the design of a self-controlled drip irrigation system based on the ideas of feedback systems and early designs of irrigation systems. Based on the exploration on metal-core indicator, a PID control system is designed which can make drip irrigation works accurately. Some further conditions are considered.
Studies and Simulations of PbPb Collisions at

sNN=2.76

TeV with the Glauber Monte Carlo Model
Authors: Zhang Jiankun , Wang Lihong , Ni Ning , Wang Pengli , Jiang Xinyun , Liu Yuxin
Published: December 2022

The main purpose of this paper is to simulate nuclear collisions. We review the theoretical background, experimental techniques, and the phenomena presented and provided by the original Glauber model and experiment. Based on the original Glauber model, we change the data and algorithm to test and compare our model with the original results. Then we figure out the spatial eccentricity of quark gluon plasma in different models and analyze the progress in the Glauber model at collider energies.
The Advantages and Applications of IGBT Compared with Conventional BJT and MOSFET
Authors: He Xibin
Published: December 2022

Nowadays, the power semiconductor devices have been used in many fields like wind power generation systems, the rail transit. Bipolar junction transistors (BJTs) and metal-oxide-semiconductor field-effect transistors (MOSFETs) as well as some other devices are the dominating the market. The insulated gate bipolar transistor (IGBT) as a mixed device of the BJT and the MOSFET, has a preeminent performance. In this paper, the characteristics of the punch through IGBT (PT-IGBT), the MOSFET and the BJT will be investigated by TCAD. Then the PT-IGBT is compared with the BJT and the MOSFET, for concluding its advantages. According to the simulation result, the PT-IGBT has the on-state current of 9*10-4A and the forward blocking voltage of 1200V, which are much higher than the other two devices. In the end of the paper, the development of the semiconductor devices is predicted, about the research trends.
Optimization Analysis on Seismic Mitigation of Building Foundation in Coastal Area
Authors: Li Zongheng
Published: December 2022

The stability of the buildings foundation in coastal areas caused by the submarine earthquake caused by the seabed plate movement has increasingly become the research focus of the engineering construction department. For the foundation under special geological conditions in coastal areas, the failure mechanism is complicated and the stress analysis is difficult. Based on the current situation of seismic design of building foundation in coastal areas, and aiming at the immature aspects of seismic treatment of foundation in coastal areas, this paper analyzes the optimization scheme of seismic design of foundation in such areas, which provides reference ideas for seismic design of building foundation in coastal seismic zones in China. In this paper, the research method is mainly through the comparative analysis of the relevant coastal engineering foundation treatment cases, the comparison of their treatment schemes and the combination of the existing foundation damping theory to summarize the suggestions on the foundation damping design under the special geological conditions in China’s coastal areas. In this paper, it is suggested that two aspects should be considered in the design of foundation vibration reduction in coastal areas: the application of dampers to reduce the vibration of foundation structures and the reinforcement of rock and soil under the foundation to meet the requirements of vibration reduction.
Dependence on Collision Centrality of Charged Particle Production at

SNN=2.76TeV
Authors: Li Qianyu , Guo Chunyu , Yuan Weisong
Published: December 2022

The ALICE collaboration provides data for particle collisions. With the help of Glauber model calculation, the collisions are categorized in to different centralities. Then, a tracklet algorithm is used on each of the centrality category. The relationship between charged particle production and collision centrality is derived, and the result is in agreement with similar work done previously.
The Progress and the State-of-Art Facilities of Inertial Confinement Fusion
Authors: Ma Zijian
Published: December 2022

Contemporarily, as a tool to address issue of energy shortage, controlled fusion has become a hot technology. Although there are ways to achieve controlled fusion, it is currently not efficient enough to produce electricity based on power plant. The topic of this paper is to introduce a method of controlled nuclear fusion derived from laser technology, inertial confinement fusion. This research analyzed from plenty of angles in terms of its development in recent years. Firstly, the article proposes the concept of fusion and inertial confinement fusion. The main contradiction is the usage of compression to achieve high ignition points. In fact, the goal of this paper is to try to reach this ignition point in various ways. After demonstrating the basic concept of the inertial confinement fusion, mathematical expression for ignition and the principle of laser, it is found that its efficiency can be increased in several ways, i.e., amplifying lasers, adding magnetic field, and shock ignition that changes the waveform. It’s still not up to production standards, but inertial confinement fusion does give a path to achieve the goal. These results shed light on guiding further exploration for ICF as well as predict the future development direction.
The Progress and Potential Applications of Quantum Anomalous Hall Effect
Authors: Deng Yuanyang
Published: December 2022

Quantum Hall effect is a very common research direction in recent years, many scientists have carried out in-depth research and experiments in this field. In this paper, the advancements and applications of the quantum anomalous Hall effect(QAHE) are being presented and discussed. Primarily, the principle and development of QAHE are analyzed. The QAHE is obtained by suppressing one of the edge states based on the quantum spin Hall effect(QSHE). The main experimental method is to add hybrid magnetic atoms in topological insulators. Since first successfully observed the phenomenon in 2013 by a Chinese group, multiple studies and experiments have been carried out on this kind of theory, and many equally important results have been obtained. Moreover, many application values and potentials of QAHE are explored. The research in this paper is helpful to deepen the understanding of the principle and experiment of QAHE and offer a guideline for further exploration.
The Progress and the State-of-Art Processes for Ultra-Intensity Laser-Driven Accelerators
Authors: Wang Hanxian
Published: December 2022

Contemporarily, with rapid development of the laser techniques, it is feasible to accelerate particles based on ultra-intensity laser. Compared to the conventional accelerators, the occupation and costs are much smaller. With this in mind, this article aims to conclude the achievement of laser acceleration in those years. In this paper, the property of the wakefield acceleration, CPA, and optical tweezer are summarized and the achievements of the state-of-art facilities are also demonstrated. However, there are still some influence factors in the acceleration, and the limitations of the laser acceleration are also mentioned. Based on the analysis, the future routine for this scheme will be proposed accordingly. Overall, these results shed light on guiding further exploration for laser-driven accelerators.