bluuebunny/crossref_metadata_2025 huggingface dataset:
A novel aerodynamic layout design of composite wing unmanned aerial vehicle based on canard configuration
Authors: Chen Yinqi
Published: November 2023

With the development of information technology and technology, more and more cutting-edge industries have come into view of the public, among which one of the most representative technologies is UAV. The emergence of UAVs has reduced the labor cost of some businesses, such as farming, forest fire prevention, maritime patrol and so on. In response to the common problems of long preparation time and poor maneuverability of unmanned aerial vehicles, this paper studies the aerodynamic layout of unmanned aerial vehicles and proposes a new layout. Firstly, the aerodynamic layout of typical UAVs is introduced and compared and analyzed. Then, a new type of compound wing UAV is designed by screening and analyzing the wing, flight analysis, main wing and UAV production process with Reynolds number. Subsequently, simulation experiments were conducted to analyze and optimize the aerodynamic layout performance of the designed UAVs, thereby verifying the reliability of the proposed method.. Finally, the entire content is summarized and analyzed.
Transit and radial velocity method for exoplanet detection
Authors: Yang Tianlin
Published: November 2023

This article introduces some basic methods that human usually uses nowadays to detect exoplanets, including transits method, radial velocity method, direct imaging method, gravitational microlensing method, and astrometry method. As we all know, none of these methods are perfect, each of them has its advantages: some of them are good at detecting planets with great mass, some are good at detecting planets with great radius, and some of the methods are good at detecting planets far away from their host star. But at the same time, each method has its own disadvantages. That is the reason why sometimes some of these methods are used together to get information about specific exoplanets. This chapter will introduce these methods by giving information on how these methods work, the equipment each of them requires, the advantages and limitations of these methods, and the history and development of these methods. Finally, there is a conclusion that states the characteristics of the planets each method is good at detecting.
Model computation and biomechanical measurements of running shoes
Authors: Zhang Yuqi
Published: November 2023

The design of running shoes is mainly to reduce mechanical stress through the deformation of the viscoelastic midsole, which is usually made of ethylene vinyl acetate (EVA) foam. This study aims to analyze and compute the heel pad stresses through simulated strikes. For stresses and strains, a non-linear model and its dierential equation (Eq.1) is reported. Through repeated measure ANOVAs, analyses and comparisons of the three methods for non-linear computation are made. Then detailed numerical approximations of a dierential equation are derived using Eulers method. In addition, Dinato reported biomechanical measures results for Air (Nike), Gel (Asics), and Adiprene (Adidas). The results are compared to simulated data correspondingly. The measured stresses (peak pressure, kPa) are 242.7 40.8, 239.5 420.0, and 246.5 51.6 respectively. The computed boundary stress is 55 kPa. These show signicant associations between the simulated and measured stress.
The contribution and role of low- and high-mass galaxies in the Epoch of Reionization
Authors: Li Kexing
Published: November 2023

Knowing the contributions and roles of both high- and low-mass galaxies during the epoch of reionization is crucial for comprehending the early cosmos and the galaxies formed in the early days of the universe. Historically, research on this topic was limited by technological constraints such as the viewable time domain of telescopes. However, technological advances and state-of-art facilities including the successful functioning of the James Webb Space Telescope (JWST) and the introduction of modern large-scale galaxy simulations have substantially improved this perplexing scenario. With this in mind, this study defines high- and low-mass galaxies during the reionization epoch and discusses how they contribute to this period in the universe's early history. The analysis introduces both the current results of astrophysicists and the limitations of scientists' research in this area. Overall, these findings show that early galaxies in the high-redshift universe are a topic with much research potential and shed light on guiding further exploration of the reionization in the universe.
Analysis of black hole merger in AGNs
Authors: Zhu Zixuan
Published: November 2023

In recent years, the phenomenon of black hole fusion in AGNs is a direction that cosmologists focus on at present. On this basis, this study will present an overall analysis of black holes mergers in AGNs. To be specific, this paper will first introduce some basic rules observed during black hole fusion. Secondly, a brief overview of black hole fusion in AGNs is given. Subsequently, the gravitational wave device (LIGO) used to detect BHs fusion is introduced in more illustration, and some relevant data on its measurement accuracy, its structure and related uses are given. After that, the authors will review several cases of BHs fusions in AGNs. At the same time, there are still several areas such as the role that gases and stars play in BH Merger and the attributes of the merged Black Hole require further exploration. Overall, these results shed light on guiding further exploration of black holes merging.
Analysis of mechanical principle of banana ball
Authors: Liu Shixian
Published: November 2023

The banana ball is a famous way to score goals in football matches. In the flight, the ball bypasses the defensive wall, giving the goalkeeper the illusion that the ball is far away from the goal, and then the ball will suddenly change direction. In order to improve the scoring probability and make training more efficient and scientific, in this article, the mechanics principle of banana ball is analyzed. A complete and comprehensive analysis of the ball motion from kick-out to flight in the air is presented. The analysis of flight considers the magnitudes of air resistance, Magnus force and Bernoulli's principle. The complete equation of motion is established. The numerical simulation by Matlab is used to simulate flight path. The flight curve of banana ball is successfully simulated. The result is consistent with real phenomenon. This article is useful for athletes and football lovers with interest in banana ball practice.
Development of RSA and some attack points
Authors: Zhang Xurui
Published: November 2023

Currently, the relatively popular public key encryption is RSA. It was officially launched in 1978 and given their initials as a name. Different encryption and decryption keys are used in the RSA public-key cryptosystem. Deriving decryption keys from known encryption keys is computationally difficult. Rsa has emerged in various forms since its development. Since the development of RSA, there have been various forms, which means there are various loopholes. Next, we will summarize several interesting attack methods of rsa. It will involve continued fractions and CRT and so on. Through this paper, one can learn a series of knowledge about rsa. As a classic asymmetric password, the value of rsa's existence is relatively high, and exploring its value is something that every password learner should experience. Through this article, one will learn about the most basic attack methods of rsa.
Airfoil design with computational fluid dynamics
Authors: Bao Henry
Published: November 2023

In many industries, there is a need to model the flow of air over structural components. With sufficient information from these models, engineers can better implement these parts into a complete design. The purpose of this paper is to provide a model of specific airfoils using computational fluid dynamics (CFD). With computational fluid dynamics, the characteristics of air around an airfoil can be modeled, providing useful data to engineers who could be designing an airfoil or airplane. The CFD calculations are performed using Python, along with the two packages Numpy and Matplotlib. The governing equations of CFD, including Newton's Second Law, small disturbance equation (SDE), wave propagation, etc. are discretized and transformed into partial differentiation equations (PDE). Using the second order derivative of the wave propagation PDE, the SDE can be solved in iterations and plotted on a graph showing the velocity distributions for a particular airfoil. The results from the CFD calculations show general trends in velocity distributions, regardless of airfoil shape. These include a decrease in x-direction velocity at the ends of an airfoil with an increase at the midsection of the airfoil. Also, y-direction velocity is generally positive and increasing at the front of the airfoil, but negative and decreasing at the end of the airfoil. What is important to understand is how different airfoil shapes can change velocity distributions, moving to using 3D CFD calculations, and the possibility of using CFD for modeling airflow over a multitude of objects.[ Henry Bao, the first author, participated in the Illinois junior academy of science state fair, and abstracts of the regional winners' presentations were posted online. (ilacadofsci.com)]
The mighty causes and influences of the great oxidation period
Authors: Bu Yi
Published: November 2023

The appearance and generation of O2 has long been discussed by the scientists. It is a fundamental topic as it can not only help us get to know the origin of lives, but can also give us the inspirations of discovering the possibilities of lives on other planets as O2 is vital to most creatures. And the GOE is the most important discovery in the O2-producing period.The appearance of the GOE was marvelous and is a great turning point in the earths developing history. Of course, the GOE cannot be simply explained as a coincidence, it is an inevitable development in the earths developing history. In this paper, we are going to focus on the mighty causes including photosynthesis in the early stage of earth and O2 storage. Also we are hunting the influences of the GOE and a relating experiment in search of the probabilities of mighty lives in the outer space.
Disney visitor problem: Integer optimization using enumeration method and set covering problem
Authors: Lin Ludwig , Aika Kajiwara
Published: November 2023

For Disneyland visitors, a well-designed route is often necessary to experience the maximum number of preferred entertainment facilities within a limited time. To construct the best way that optimizes visitors satisfaction, a survey is first conducted to estimate the attraction value of each facility, followed by the collection of data that record the traveling time among each facility and the waiting line time. Using collected data and listed constraints, a possible route is listed as an example. To solve the problem, a model is constructed based on integer linear programming. The original, incomplete, and modified formulations are listed in the last part of this paper.
Numerical analysis of the effects of the nozzle shape and outlet area of a waterjet propulsion system on its efficiency
Authors: Wei Mingxiao
Published: November 2023

The waterjet propulsion system is a marine propulsion device prevalently used on contemporary high-speed vessels. The performance of a waterjet propulsion system is considerably affected by the nozzle. In this study, the influences of the shape and the outlet area of a waterjet propulsion system on the efficiency of the propulsion system is investigated using the computational fluid dynamics method. A total of 10 different nozzle designs, including cylindrical and conical nozzles with 5 different outlet areas, are analyzed in terms of nozzle efficiency and overall efficiency, and the possible reasons and explanations behind the variations of the nozzle efficiency and the overall efficiency are proposed in this study. The simulated results indicate that the conical nozzles consistently have higher nozzle efficiency than the cylindrical nozzles, and the maximum nozzle efficiency occurs in the conical nozzle with an outlet area of 60% of the inlet duct area. The abrupt change in the flow direction at the transition between the guide vane section and the nozzle, as well as the skin friction on the nozzle wall, are predominant factors affecting the nozzle efficiency. The waterjet propulsion units equipped with conical nozzles generally have higher overall efficiency than their counterparts equipped with cylindrical nozzles, while the maximum overall efficiency occurs in both the cylindrical nozzle with an outlet area of 50% of the inlet duct area and the conical nozzle with an outlet area of 60% of the inlet duct area. The loss of mechanical energy due to viscosity and turbulence in a propulsion unit is the major source of energy loss, while the kinetic energy carried by the exit flow is also a considerable factor affecting the overall efficiencies of the propulsion units equipped with conical nozzles with relatively large outlet areas.
Galaxy formation and evolution
Authors: Xu Zeyue
Published: November 2023

Galaxies as the most important structures in the universe and Galaxy formation is a sequential redistribution process.The basic picture of galaxy formation was first proposed by White and Rees.The physical processes involved in galaxy formation are very numerous and complex. We know very little about most of these processes. Therefore, we can only describe them with a few empirical formulas. In this article the popular simulation techniques for galaxy formation are discussed in detail, based on the most recently observed cosmic star formation history. This study will focus mostly on the goals of galaxy development by describing the processes of star formation, gas dispersion, dark matter, and galaxy correlation. In this paper, we do not study the formation process of a specific galaxy, but focus on the formation process of a large sample of galaxies in the framework of the whole cosmology We are also concerned not with the specific properties of a particular galaxy, but with the statistical properties of the whole sample of galaxies.Therefore the paper will next explore hydrodynamic techniques such as N-body simulation, other modified f (R) gravity models, smoothed-particle hydrodynamic simulation, and semi-analytic models to mimic the process of galaxy formation. This article finishes with a summary of galaxy formation.
Exploring projective equivalences between closures of orbits
Authors: Qiu Christopher
Published: November 2023

Motivated by results in the literature that use representations and group actions to produce nice geometric results about algebraic varieties, this article studies projective equivalence relations between closures of orbits for several complex algebraic group actions on , where is a complex representation of . In particular, we study the cases when is one of the following:, , , and . On the way, we also obtain some interesting geometric results from studying these orbits.
Effect of roof design on wind load of buildings through numerical simulation
Authors: Li Yuxin (April)
Published: November 2023

When the wind blows against a building, the resulting force acting on the building at a particular elevation is called the wind load. Measuring and minimizing the wind load is crucial to ensure the safety of buildings. Therefore, the objective of this study is to investigate the effect of a buildings roof design on the wind load by evaluating and comparing the wind pressure differences p that different building models experience by leveraging Computational Fluid Dynamics (CFD) simulations. The 3D CAD (Computer-Aided Design) software SolidWorks was used to construct building models of identical dimensions with the exception of roofs harboring different shapes and angles. By exerting a wind velocity through flow simulation, flow trajectories and cut plot graphs of wind velocity and pressure surrounding the building models are generated. Wind pressure differences p for each situation were calculated and compared based on the CFD results. Wind tunnel experimentation with building models will also executed to test the computed data and prove its reliability and applicability. The data shows that, among all tested roof designs, the barrel-vaulted roof exhibits the minimum pressure difference (of 171.15 Pa) between the windward and the leeward surface and experiences the least wind load and resists strong wind most effectively. It reduces up to roughly 15% of wind load compared to the worst case tested. For symmetric triangular gable roof designs, the greater base angle leads to greater wind load. Overall, this study provides the theoretical basis and scientific evidence for the building designs of the next generation.
The challenges of nuclear fusion reactor
Authors: Yao Qikai
Published: November 2023

Energy shortage is one of nonnegligible problems nowadays. Even since the twenty centuries, the achievement of fission reactor has proved that nuclear energy is a powerful source. However, fission reaction could cause radiation hazard if operation error happens. Nuclear fusion can provide more clean energy. This paper discusses nuclear fusion and two typical models of fusion reactor, inertial confinement fusion reactor and tokamak, and their properties. Fusion reactors use deuterium and tritium to fuse heavier nucleus and release energy. With -distribution, deuterium-tritium fusion reactivity can be boosted at relatively low temperature. Furthermore, fusion reactor has initial success. The more energy can be created than energy used to ignition. To solve nuclear fuel problem, continue ignition progress problem, possibly achieving controllable fusion reaction. The improvements which this paper mentioned perhaps allow to extend the application context of fusion reactor.
A design review on hypersonic aerodynamics configurations and applicability to hypersonic transports
Authors: Gao Yidi
Published: November 2023

As the world of commercial aviation recovers from the global recession after the pandemic, demands for faster and more reliable air transportation are on the rise. Research in Hypersonic Transports, led by both government and private sectors, aims to revolutionize the industry with its high time efficiency and customizability for various needs. This paper reviews the design principle and challenges of HST from a technical standpoint, while overviewing high-speed gas dynamics, analyzing the waverider configurations, and addressing the technical intricacies of designing a hypersonic vehicle. It shows that the waverider configuration is a suitable HST candidate for its large fuel storage and high inlet compatibility for an airframe-propulsion integrated design. This paper aims to provide holistic context for the advantages and challenges associated with HST, while providing insights into the compatibility of a waverider configuration that can be optimized for civilian transport applications.
The basis of unified field theory and the direction of future development
Authors: Wu Chentai
Published: November 2023

Unified field theory is a physical theory that describes and reveals the common nature and intrinsic connections of fundamental interactions in a unified way, starting from the idea that interactions are transmitted by fields. This paper will start from the past of the unified field theory and use the literature research method to describe the problems encountered in completing the unified field theory and the possible solutions for the future. The result shows that unified field theory is a dynamic theory that is still being studied and has significant implications for the development of physics. This article argues that many of the shortcomings of this theory are due to the lack of mathematical theory. It is also pointed out that the creation of a new mathematical system is a feasible way. Finally, it is concluded that unified field theory is still a very difficult problem to explore.
Analysis of faster matrix multiplication
Authors: Liu Jie
Published: November 2023

Since the definition of matrices in 1855, matrix multiplication has played a crucial role in a wide range of fields. Over the years, numerous researchers have dedicated their efforts to improving the time complexity of this fundamental operation. This paper aims to delve into the historical development of matrix multiplication algorithms and methodologies employed to achieve these significant advancements in time complexity. By employing various approaches, researchers have been able to improve the time complexity of matrix multiplication, leading to a significant reduction from O () to O (). Across nearly two centuries, this progress is contributed by a lot of extraordinary scientists and researchers. This paper explores the practical implications of these improvements across various domains, such as computer science, physics, economics, and more. The development of more efficient matrix multiplication algorithms has enabled researchers and practitioners to tackle complex problems and explore new frontiers. In the future, with the rapid growth of machine learning techniques, matrix multiplication will continue to evolve and improve.
Research on the application of Markov chain
Authors: Kwok Aaron
Published: November 2023

In modern times, mathematicians are often troubled by new approaches to deducing the outcomes of certain events. The introduction of Markov models eliminated queries across different sectors. In 1907, Russian mathematician Andrey Markov proposed the concept of Markov chains. It has been widely used in many aspects, such as weather prediction, deep learning, biological information, and so on. Therefore, this paper examines how the Markov chain model can be applied in a variety of situations. This study uses Python as a supporting tool to simulate states and possible outcomes. It can be concluded that Python is able to simulate the state transitions of the Markov chain. The paper also identifies the differences between Markov models, their application in common scenarios such as medical, finance, weather forecasting, machine learning and others in our everyday life and why they are so popularly used, including the simplicity of the model and more.
Comparing different types of engines and efficiency-a literature review
Authors: Zhang Min
Published: November 2023

The goal of this research was to evaluate and contrast the performance of various engine types. The study was conducted on a sample of two engines, one of which is an Internal Combustion engine and the other is an External combustion engine. The internal combustion engine has two cycles, Otto cycle is used in gasoline engines while the diesel cycle is used in diesel engines. The external engine has two cycles too, the submarine uses Stirling Cycle and the Thermal power plant uses the Rankine cycle. The engines were evaluated based on their thermal efficiency, brake power, and specific fuel consumption. The results showed that the diesel cycle had higher thermal efficiency and brake power compared to the Otto cycle. However, the two-stroke engines had lower specific fuel consumption compared to the four-stroke engines. The results indicate that each engine type has advantages and disadvantages and that the final decision should be based on the needs of the given application.
Analyzing light curves to highlight phenomena and trends in planetary systems that house terrestrial exoplanets
Authors: Cao David Lu
Published: November 2023

Light curves describe the luminosity, or flux, emitted by celestial bodies or systems over a period of time. Since light curves are mostly irregular and may contain spikes and dips caused by extraneous factors, they contain valuable information about various phenomena and trends in the observed planetary system. For instance, light curves often help detect exoplanets in a stars planetary system. Furthermore, they also help characterize solar flares, cataclysmic variables (CVs), and various other phenomena. This study collects data in the form of light curves from stars in planetary systems housing terrestrial exoplanets found on the NASA Exoplanet Catalog and explored various causes for variations in the planetary systems light curve. One significant finding from light curve analysis was the possible existence of instrumental noise on the Kepler telescope in quarter 10. However, a larger exoplanet sample size and a real significance test are required for confirmation. This study exemplifies the accessibility and therefore feasibility of gathering data, graphing, and analyzing light curves.
On nonsingular bilinear maps over different fields
Authors: Feng Ruoxuan
Published: November 2023

The investigation of nonsingular bilinear forms originates from the classification of division algebras over the real number field. Building upon this foundation, researchers have delved into the study of nonsingular bilinear forms over real number fields, leading to significant results such as Hopfs theorem. However, the interest in understanding nonsingular bilinear forms extends beyond real number fields, prompting a desire to explore other fields as well. When it comes to algebraically closed fields, the theorem becomes well-understood, with essence captured by the Hopf-Smith theorem. Inspired by these established studies, we are motivated to further the comprehension of nonsingular bilinear forms over arbitrary fields. Given a field , we study in this article numerical constraints on for the existence of nonsingular bilinear maps for not only algebraically closed fields and the real number field but also the rational number field and finite fields. We reach the final conclusion mainly through algebro-geometric techniques and the use of determinantal varieties. We reprove a result of HopfSmith which states that the minimal possible value of is when is an algebraically closed field. When is the real number field, we prove that under a combinatorial condition, the minimal possible value of is still . We also show that when is the rational number field or a finite field, the minimal possible value of is .
Life expectancy analysis based on multiple linear regression analysis
Authors: Liu Runmeng
Published: November 2023

One of the most significant subject matters in contemporary research is life expectancy. The researchers discovered that although the contributing elements of life expectancy have been extensively addressed, there has not yet been any direct connections between them. In order to looking into the relationship between life expectancy and 14 relevant influencing factors as well as the variations in these relationships, this research performed multiple linear regression analysis on the life expectancy data gathered from the website Kaggle. In accordance with the study, several aspects that individuals believed were important but did not in fact affect life expectancy could not be explained by overly specific variables. Researchers can use this finding based on the multiple linear regression method to investigate the similarities and differences between life expectancy and different influencing factors, for the purpose to come up with more effective recommendation to improve the life expectancy and health level of the population.
Analysis of the stokes problem in a regular bounded open set
Authors: Yu Qingyue , Huang Zinian
Published: November 2023

The Stokes equation describes the flow velocity of a steady state fluid in relation to the pressure and the external source. The corresponding variational formulation of the Stokes equation is studied in the paper. In more detail, we delve into the analysis of the equivalence relations pertaining to the variational formulations of the Stokes equations. We found that the variational formulation of the Stokes equation can be approximated by a type of variational formulation with a coefficient but without the constraint on the divergence. Then we did a analysis on the approximation by the finite element method to the the variational formulation without the constraint on the divergence, and we find that we should use preconditioning techniques before using the iteration. More precisely, we give an error analysis of this numerical computation method through rigorous proofs, and from this we deduce the need to use preprocessing techniques to avoid long computation times.
Analysis of the application of the air suspension system of pure electric vehicle
Authors: Cheng Liang , Kang Zhuang , Zeng Jixian
Published: November 2023

Air suspension is a component that connects wheels and bodies and conducts force and moment by reaction force of air spring gas compression. The air suspension system exhibits notable merits in terms of enhanced driving comfort and stability, coupled with the ability to adjust multiple parameters. Consequently, examining the advantages of air suspension can serve as a theoretical foundation for the selection of automobile suspension systems. Furthermore, elucidating the benefits derived from the utilization of air suspension can facilitate subsequent studies by providing clarity and directness. In this paper, the advantages and disadvantages of air suspension are analyzed, and the semi-active control of air suspension is discussed, different parameters of air suspension can be controlled by the system. The limited adoption of air suspension systems can be predominantly ascribed to the substantial financial investment required for their installation and upkeep, including both higher initial costs and ongoing maintenance expenses. Accordingly, it has better driving comfort and stability than traditional mechanical suspension and can be controlled by the control system. Semi-active control of air suspension may make it closer to ideal performance in actual work by optimization and a combination of new technologies.
Seeing cells without a lens: Compact 3D digital lensless holographic microscopy for wide-field imaging
Authors: Yang Thomas Zhirui , Wu Yumin
Published: November 2023

Optical microscopy is an essential tool for biomedical discoveries and cell diagnosis at micro- to nano-scales. However, conventional microscopes rely on lenses to record 2-D images of samples, which limits in-depth inspection of large volumes of cells. This research project implements a novel 3-D lensless microscopic imaging system that achieves a wide field of view, high resolution, and an extremely compact, cost-effective design: the Digital Lensless Holographic Microscope (DLHM).A lensless holographic microscope is built with only a light source, a sample, and an imaging chip (with other non-essential supporting structures). The entire setup costs $500 to $600. A series of MATLAB-based algorithms were designed to reconstruct phase information of samples simultaneously from the recorded hologram with built-in high-resolution and phase unwrapping functions. This produces 3-D images of cell samples. The 3-D cell reconstruction of biological samples maintained a comparable resolution with conventional optical microscopes while covering a field of view of 36.2 mm2, which is 20-30 times larger. While most microscopes are extremely time-consuming and require professional expertise, the lensless holographic microscope is portable, low-cost, high-stability, and extremely simple. This makes it accessible for point-of-care testing (POCT) to a broader coverage, including developing regions with limited medical facilities.
Overview of the nature and development of gambling from the perspective of probability
Authors: Shen Siyi
Published: November 2023

In 1654, Pascal and Fermar discussed how two gamblers should fairly divide their winnings after a break in play, and they came up with the right answer for the first time. Many gamblers are convinced that luck is always on their side and the odds of victory are always in their hands because gambling that is based on random games does not require too many skills and strategies to gamble based on the gambler's luck and competitiveness. Can gambling activities that draw large numbers of gamblers actually result in a profit? Making a lot of money through sheer luck is a pipe dream, according to the principles of probability that govern random games like winning and losing in gambling. This paper employs a method based on literature reviews to first assess the core of gambling from a probability perspective, then discuss the previous contributions of gambling, and lastly discuss the significance of probability and the future development of gambling.
Research on the bidirectional sliding phenomena of a toppling rod under frictional situations
Authors: Guo Haoxiang
Published: November 2023

In this work, we investigated the phenomenon of spontaneous bidirectional sliding on a toppling rod under a frictional situation. We explained the reasons for sliding is the friction force from the table is not sufficient to support the horizontal acceleration of the mass center when toppling, so the rod itself has to obtain a horizontal acceleration and apply the inertia force to play the role of supporting the acceleration of the mass center. This phenomenon and converted the question into a mathematical model. We pick the contacting point between the rod and the horizontal surface as the reference point for our computing of physical quantity, therefore the torque caused by friction and normal force can be ignored. With this model, we finished the theoretical analysis of the effects of varying static friction and dynamic friction coefficients on the phenomenon, with computer simulations verified.
Analysis of Majorana-based quantum computation
Authors: Bi Yutong
Published: November 2023

In recent years, the realization of quantum computation is a compelling research direction. To realize an error-tolerate quantum computer, topological quantum computation is considered as the most promising direction. Plenty of scholars have proved that non-abelian particles may play an important role on it. As a matter of fact, among particles obey non-abelian statistics, Majorana fermions is a typical example. On this basis, this study aims at introducing the development of Majorana-based quantum computation. To be specific, it will contain the conceptual framework of topological computation and introduce some recent research about Majorana-based quantum computation including the principles, configurations as well as the state-of-art analysis results. In addition, the current limitations for these studies will be demonstrated accordingly. Moreover, based on the summary the development of this field in recent years, this research will provide reference direction for future researchers. Overall, these results shed light on guiding further exploration of quantum computers.
Effect of front windshield angle on drag coefficient of electric vehicles
Authors: Gao Chenxi
Published: November 2023

This research explores the relationship between the drag coefficient and front windscreen angles regarding to automobile engineering. The previous research indicates that the best angle for the front windscreen to reduce the drag coefficient was less than 45 degrees, and the tilt of the bonnet has a linear relationship with the drag coefficient. However, the ideal angle for the windshield to achieve the lowest possible drag coefficient is also governed by other factors such as road roughness and overall aerodynamic design. As 2D simulations can prove to be an invaluable resource for aerodynamic design, allowing designers to make sharp changes and test new ideas efficiently on the digital stage, this paper uses NURBS modelling techniques and ANSYS CFD-Post to predict liquid dynamics, further enhancing the prediction of the simulation. It can be concluded that reducing the drag coefficient will increase the range of electric vehicles, especially in severe weather conditions like winter. Overall, reducing air resistance has several positive effects on a vehicle, including stability, energy consumption, acceleration, and forward speed.
Status quo and improvements of timekeeping in GNSSs
Authors: Liu Haofeng
Published: November 2023

A time offset of 1 microsecond could lead to 300-meter positioning offset for a global navigational satellite system (GNSS). Therefore, appropriately evaluating and improving the clock performance onboard GNSS satellites are critical. The research methods and conclusions of papers written in distinct periods about their contemporary satellites clocks are chronologically synthesized. The satellites clocks among the same and different GNSSs are compared, with the time primarily centered around the launching and development of BeiDou-2 and BeiDou-3. It is found that passive hydrogen maser (PHM) and rubidium atomic frequency standard (RAFS) have a better performance than cesium (Cs) clocks, and PHM are among the best clock onboard satellites so more attention may be given to its development. Two major factors affecting timekeeping precision are the selection of clock manufacturers and clock types. The European manufacturing technique is pioneering, but the RAFS and PHM independently developed by China in recent years indicate a good performance. To improve navigation service, an accurate evaluation of satellites performance should be conducted, and the results can be used to assign the weight of satellite differently in computing navigation information.
Turbofan and turbojet engines: Working process and future development
Authors: Wei Kaixiang
Published: November 2023

This article is based on the fundamental thermodynamics theory to analyze the difference between the turbojet and turbofan engines. The result of this article is that the turbofan engine is suitable for commercial use since it consumes less fuel and has a higher bypass ratio than the turbojet engine. But low bypass ratio engines can serve the military since they have a smaller volume and higher speed, suitable for air combat. The turbojet engine can travel at a supersonic speed since it has extremely high jet flow from the nozzle and much higher fuel consumption, so it is for military use. This article also analyses two cases: i) How the number of fan blades and outlet guide vans affects the noise of the engine produced. ii) When airplanes fly through volcanic ash, how does the ash damage the airplane and the engine? The engineer found that 55 outlet guide vans are better than 37. To prevent airplanes from flying through volcanic ash, satellite weather photos start to show the volcanic ash area.
Enhancing alpha solar stirling engine performance with regenerator
Authors: Wu Kaiyi
Published: November 2023

Nowadays, as traditional fossil energy sources are in decline, renewable energy sources are being actively sought, and the use of renewable energy is receiving widespread attention. The Dish engine solar power plant is vital in using solar energy. The Stirling engine is the fundamental element of the power plant, responsible for energy conversion. And the internal regenerator has an essential influence on the engine's performance. Hence, this paper focuses on the analysis and improvement of the regenerator. Heat transportation determines its efficiency, while the regenerator is the core component. An efficient Stirling engine cannot occur without a high-quality regenerator. This paper uses simulation experiments to explore the impact of various materials on the regenerator's performance. By comparing the regenerator performance of filled copper foam and stainless-steel mesh, it was found that the copper foam regenerator had a faster start time, while the stainless-steel mesh regenerator had a higher thermal capacity. After this conclusion, an optimized regenerator is designed, filled with different materials at each end according to the material properties. After simulations, it can be concluded that this enhancement improves the regenerator's performance, increasing the Stirling engine's overall efficiency.
Integrated circuit design based on CMOS technology principle and its application in GPU
Authors: Chen Jiahao
Published: November 2023

In today's society, the application of integrated circuit technology can be seen everywhere, especially in the past two decades. This paper mainly studies the principle and design of CMOS devices in IC technology and discusses the research and analysis of the acceleration algorithm of IC design. This paper adopts the research method of literature review and analysis to summarize the existing research results. This paper first introduces the development background of integrated circuit technology and the importance of CMOS technology. Subsequently, the concept and interconnection principle of CMOS device, and the combined circuit design and sequential logic circuit design principle of dynamic and static CMOS are explained in detail. Then, the application principle of CMOS technology in GPU is analyzed, and its specific application in GPU acceleration algorithm is analyzed. Finally, the application of CMOS technology in integrated circuits and its application and acceleration effect are summarized.
Circuit defect detection based on AI deep learning
Authors: Wang Luozhi
Published: November 2023

In the milieu of promptly advancing technology and increasing demand for electronic devices, circuit defect detection has become crucial to warranting product quality. This study tackles the cons of traditional defect detection methods, proposing a mind-boggling approach based on AI deep learning. The study intends to establish and enhance deep learning algorithms for the exact and real-time detection of circuit defects. This research encompasses an in-depth review of existing literature on circuit defect detection and AI deep learning, underlining the existing gaps and pitfalls in the field. The study will primarily deploy convolutional neural networks (CNNs) and recurrent neural networks (RNNs) as the primary tools to process various data modalities. The results highlight that the proposed AI deep learning framework depicts grander performance, unlike in traditional manual inspection. The study sets precedence in AI applications in quality control as it contributes to improved manufacturing efficiency, reduced production costs, and delivery of utmost-quality electronic products to consumers.
Advanced development and future of jet engines
Authors: Chen Ruiyang
Published: November 2023

An aerodynamic reaction engine, a jet engine, is an internal combustion engine that produces thrust through jet thrust. A jet engine is an important power unit used in aviation and spaceflight, which generates thrust by pushing air in reverse. In recent decades, various developments and improvements have significantly enhanced the efficiency and performance of jet engines. These engines are divided into turbojets, turbojets, turboprops, turboshafts, and ramjets. This article will begin with an introduction to the different types of jet engines and then detail the design, benefits, and issues of the CFM International CFM56/LEAP engine. Finally, there is some description of the future of jet engines, including materials, greater efficiency, and applications in space exploration. The development of the jet engine dates back to the 1930s. British inventor Frank Whittle and German inventor Hans von Ohain developed the first jet engines independently. Jet engines were widely used during World War II and have been continuously improved and developed. The modern jet engine has become the main power unit of commercial and military aviation, and its structure and performance have also been greatly improved.
Analysis of the application of Fibonacci sequence in different fields
Authors: Liu Zhiheng
Published: November 2023

Fibonacci, an Italian mathematician, discovered the Fibonacci series after investigating an issue involving the reproduction of rabbits. This series is a very essential series that is utilized extensively across a wide variety of professional application domains. The objective of this paper is to present abstracts of five mathematical subjects in the hopes of throwing light on the significance of these topics as well as the practical applications they have. The author's goal is to illustrate the depth and breadth of mathematics, as well as the ways in which it permeates a variety of different fields, by doing a literature study and then addressing the aforementioned themes. Each summary will focus on a different topic of mathematics, such as statistics, geometry, calculus, number theory, and mathematical modelling. These summaries assist readers get a more in-depth grasp of the various areas of mathematics and an appreciation for the impact those branches have on our everyday lives.
Working principle of the radio telescope and the study of the sun
Authors: Hong Yiduo
Published: November 2023

Radio telescopes can help people observe celestial bodies far away from people, which is conducive for astronomers to observe and draw the trend of celestial transformations. The use of radio telescopes allows scholars to study and understand celestial bodies to a new height. At present, the more famous are the Webb Space Telescope in the United States, the Hubble Space Telescope and China's Tianyan. In the case of the eye of Heaven in Guizhou, China, the surface of the eye is covered by a metal layer one millimeter thick, so it can not withstand excessive pressure, and the maintenance personnel need to attach themselves to a giant helium balloon to reduce their weight, the whole process is so careful to ensure the safety of the precision instrument. So there are still some limitations in the development of radio telescopes. This paper will focus on the working principle of the radio telescope, the development of the radio telescope and techniques for observing the sun with radio telescopes, summarize the achievements of the radio telescope so far and the areas that need to be improved. To better understand radio telescopes.
Updated estimate for the dark matter density in the milky way
Authors: He Yiwei
Published: November 2023

Compelling evidence are present about the presence of dark matter in the Universe observing different astrophysical sources from closer cluster of galaxies up to individual galaxies. One of the possible interpretations for these observations is that dark matter is made by one new particle which is neutral, weakly interacting, massive and stable. One of the most important ingredients to study dark matter is its density in the Milky Way. In this paper we study the density of dark matter using the measurement of the local density as well as the total mass in the Galaxy. We also fit the measured rotational curve data and find that the evidence for dark matter for large radii is compelling. The known astrophysical material as gas and stars cannot fit well the velocity observed in the Galaxy beyond a few kpc from the center.
Structure and application of flexible MOFs materials
Authors: Li Yiming
Published: November 2023

The research on MOFs materials is currently a hot topic in the academic community. From the existing research results, it can be seen that the structure and composition of MOFs materials have been thoroughly studied. However, the relevant research on the application and research prospects of MOFs materials, especially MOFs flexible materials, is still not perfect. Based on the above research motivation, the research content of this article focuses on the structure and application prospects of flexible MOFs materials, and mainly draws the conclusion that they have enormous development potential and attractive development prospects in modern material research.