Theoretical and Natural Science最新文献_第7页

Metronome synchronization in the presence of friction 有摩擦时的节拍器同步

Theoretical and Natural Science Pub Date : 2024-03-07 DOI: 10.54254/2753-8818/31/20240888

Wenqian Wu

{"title":"Metronome synchronization in the presence of friction","authors":"Wenqian Wu","doi":"10.54254/2753-8818/31/20240888","DOIUrl":"https://doi.org/10.54254/2753-8818/31/20240888","url":null,"abstract":"This study investigates the synchronization phenomenon inherent to mechanical metronomes. Synchronization properties were probed under diverse conditions, with modifications to parameters such as the number of metronomes, the tabletop material, the additional weight on the platform, and the friction coefficient between the roller and platform. Experimental outcomes demonstrate that the synchronization is significantly influenced by the platform's movement, which is subsequently determined by the properties of both the platform and roller. An analytical modeling approach provided insights into these effects, particularly when analyzing two metronomes placed on a flat platform equipped with rollers. Central to the findings is the revelation that both the coefficient of friction and the mass of supplementary weights play crucial roles in shaping synchronization behavior, a conclusion in line with experimental observations. The numerical segment of the study leveraged the Kuramoto model. Observations centered on the phase variation of resonators and a time-responsive order parameter, shedding light on the role of coupling strength in synchronization and its absence. Overall, this study furnishes a thorough theoretical and experimental exploration of mechanical metronome synchronization, targeting an enhanced understanding and application of the observed phenomenon.","PeriodicalId":506830,"journal":{"name":"Theoretical and Natural Science","volume":"79 2","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-03-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140077587","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

The origin, development, and application of fractal geometry theory in architecture 建筑学中分形几何理论的起源、发展和应用

Theoretical and Natural Science Pub Date : 2024-03-07 DOI: 10.54254/2753-8818/31/20240914

Yifei Guan, Simi Liu, Yiwei Zhang

{"title":"The origin, development, and application of fractal geometry theory in architecture","authors":"Yifei Guan, Simi Liu, Yiwei Zhang","doi":"10.54254/2753-8818/31/20240914","DOIUrl":"https://doi.org/10.54254/2753-8818/31/20240914","url":null,"abstract":"Fractal geometry plays a crucial role in the study of fractals, with wide-ranging applications and it is closely related to architectural design creation, notably in architecture. Fractals are becoming more prevalent in todays society and can be used to describe a variety of extremely irregular items in the actual world. This article aims to provide an overview and analysis of the significant implications of fractal geometry in architecture, exploring its relationship with elements in nature, such as trees. By searching, organizing data, and elucidating examples, the article delves into the origin and basic background of fractal geometry. The use of fractal geometry in architecture demonstrates the perfect symbiosis between fractal and nature through analysis of TOD, the ancient gardens in Suzhou, and other practical applications. One notable fractal algorithm is the L-system, a modeling approach expressing fractal concepts, enabling parameterization and architectural design. Fractal geometry successfully expands possibilities for the harmonious coexistence of architecture and nature, embodying numerous natural features and human-centric ideas.","PeriodicalId":506830,"journal":{"name":"Theoretical and Natural Science","volume":"2 26","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-03-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140258590","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Portfolio selection methods and efficiency research 投资组合选择方法和效率研究

Theoretical and Natural Science Pub Date : 2024-03-07 DOI: 10.54254/2753-8818/31/20241114

Tian Qin

引用次数: 0

Comparative study of riemann integral and lebesgue integral in calculus 微积分中的里曼积分和勒贝格积分的比较研究

Theoretical and Natural Science Pub Date : 2024-03-07 DOI: 10.54254/2753-8818/31/20240731

Qiuran Dong, Yifan He

{"title":"Comparative study of riemann integral and lebesgue integral in calculus","authors":"Qiuran Dong, Yifan He","doi":"10.54254/2753-8818/31/20240731","DOIUrl":"https://doi.org/10.54254/2753-8818/31/20240731","url":null,"abstract":"The aim of this research paper is to provide a comprehensive comparison between Riemann integral and Lebesgue integral. Integration is described as the inverse process of differentiation, which is used to determine the original function. Riemann integration is a specific type of definite integral applied to find the exact area under a function graph between two limits in a closed interval. Lebesgue integration, on the other hand, provides a more generalized framework for integration theory. Integrals are essential in mathematical modelling and analysis tools. Studying and comparing the similarities and differences between these two integration methods can help us better understand the essence and properties of integrals, so as to more accurately apply integration methods to solve practical problems. This paper provides a systematic analysis of the basics, definitions, concepts, and properties of Riemann integral and Lebesgue integral. Reasoning, proofs, and examples are consolidated to explain the properties and characteristics of these two integral methods. Finally, this paper explores the strengths and limitations of each integration methods, summarising their advantages and applicability to practical problems and providing insights into their respective computational methods and applicability in different contexts.","PeriodicalId":506830,"journal":{"name":"Theoretical and Natural Science","volume":"6 3","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-03-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140260447","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

On Euclidean, spherical and hyperbolic crystallography 关于欧几里得、球面和双曲晶体学

Theoretical and Natural Science Pub Date : 2024-03-07 DOI: 10.54254/2753-8818/31/20241107

Zhengjie Yan

引用次数: 0

Research on network intrusion detection based on XGBoost algorithm and multiple machine learning algorithms 基于 XGBoost 算法和多种机器学习算法的网络入侵检测研究

Theoretical and Natural Science Pub Date : 2024-03-07 DOI: 10.54254/2753-8818/31/20241171

Zhihui Fan, Zhixuan You

{"title":"Research on network intrusion detection based on XGBoost algorithm and multiple machine learning algorithms","authors":"Zhihui Fan, Zhixuan You","doi":"10.54254/2753-8818/31/20241171","DOIUrl":"https://doi.org/10.54254/2753-8818/31/20241171","url":null,"abstract":"Network intrusion detection refers to monitoring and analysing network traffic, system logs and other information to identify abnormal behaviours and attacks in the network, and take timely and appropriate countermeasures to protect the security and stability of the network. This paper investigates the application of seven machine learning methods in network intrusion detection, and evaluates each model by indicators such as precision, accuracy, recall and F1 score. The results show that XGBoost, Random Forest and Decision Tree models have the best prediction results, while Support Vector Machines and Plain Bayes models have poor prediction results. XGBoost, Random Forest and Decision Tree models all belong to the category of integrated learning, which have strong generalisation ability and robustness, can handle high-dimensional and complex datasets and are not prone to overfitting. In addition, they are able to handle non-linear relationships and are suitable for complex classification problems. Catboost and logistic regression models have better prediction results, but their prediction results are also affected by feature engineering. They may under- or over-fit when dealing with high-dimensional, complex datasets. Support Vector Machines and Plain Bayesian Models have poorer prediction results, which is related to their limitations. Support vector machines may experience computational difficulties when dealing with high-dimensional, complex datasets and are weak in dealing with non-linear relationships. The plain Bayesian model assumes that the features are independent of each other, which may not hold true in practical applications, thus affecting the prediction results. The conclusions of this paper are instructive for research and application in the field of network security, and can provide reference and inspiration for research in related fields.","PeriodicalId":506830,"journal":{"name":"Theoretical and Natural Science","volume":"30 6","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-03-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140259547","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

An in-depth analysis and derivation of extremum conditions based on gradient information 基于梯度信息的极值条件的深入分析和推导

Theoretical and Natural Science Pub Date : 2024-03-07 DOI: 10.54254/2753-8818/31/20241121

Honghao Yang, Guizhong He

引用次数: 0

Integrating GBDT regression and factor analysis for accurate prediction of used sailboat prices 整合 GBDT 回归和因素分析，准确预测二手帆船价格

Theoretical and Natural Science Pub Date : 2024-03-07 DOI: 10.54254/2753-8818/31/20241126

Haojie Yang, Ruiqi Yao, Qing Zhu, Jialei Huang

{"title":"Integrating GBDT regression and factor analysis for accurate prediction of used sailboat prices","authors":"Haojie Yang, Ruiqi Yao, Qing Zhu, Jialei Huang","doi":"10.54254/2753-8818/31/20241126","DOIUrl":"https://doi.org/10.54254/2753-8818/31/20241126","url":null,"abstract":"Similar to many luxury goods, the value of sailboats fluctuates with the age of the boat and market conditions. To comprehensively understand the sailboat market, our team utilized web crawlers to collect data on second-hand sailboats and relevant regional factors (economic, geographic, tourism). We established a unified prediction model that integrates sailboat characteristics and regional influences. Using a factor analysis model, combined with a Gradient Boosting Decision Tree (GBDT) regression model, we evaluated the regional impact on second-hand sailboat prices. The combined model demonstrated high accuracy in predicting the prices of monohull and catamaran sailboats. The study further explored the applicability of the model to the Hong Kong market and validated its effectiveness with different datasets. The results indicated substantial demand and tremendous market potential in the Hong Kong market. Finally, through ARIMA time series forecasting, statistical histograms, and correlation analysis, the study revealed relationships between year and price, regional disparities, and key price-influencing factors.","PeriodicalId":506830,"journal":{"name":"Theoretical and Natural Science","volume":"18 2","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-03-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140260037","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Thermal-Hydraulic performance of microchannel heat sink designed with counter-flow and different groove shape 采用逆流和不同槽形设计的微通道散热器的热工水力性能

Theoretical and Natural Science Pub Date : 2024-03-07 DOI: 10.54254/2753-8818/31/20241141

Ruize Liu

{"title":"Thermal-Hydraulic performance of microchannel heat sink designed with counter-flow and different groove shape","authors":"Ruize Liu","doi":"10.54254/2753-8818/31/20241141","DOIUrl":"https://doi.org/10.54254/2753-8818/31/20241141","url":null,"abstract":"Microchannel heat sink is a potential procedure for scatter heat as a result of its little size and high effectiveness. Thermal resistance and pumping power are two significant parameters to assess the behavior of microchannel heat sink. In this review, heat transfer and fluid behavior have been concentrated mathematically in a microchannel heat sink with the counter stream and different shape of the groove. Four unique cases are discussed in this paper, microchannel heat sink with rectangular groove (R-MCHS), microchannel heat sink with circular groove (C-MCHS), microchannel heat sink with triangular groove (T-MCHS), and straight microchannel heat sink (S-MCHS). Three-dimensional numerical simulation is conducted with the Reynolds number, Re, shifting from 100 to 500 with expanding 100 for each step. As the coolant, Single-stage fluid water streams in the heat sink. The thermal and hydraulic performance of these cases are evaluated by comparing the average temperature of the solid domain, Nusselt number, Thermal Resistance, and Pumping Power. Contrasted with the S-MCHS, the thermal performance of MCHSs with grooves is increased, and the Nusselt number increased at the furrow area. Likewise, the pumping power is bigger for all cases with grooves contrasted and S-MCHS. In all grooved cases, R-MCHS has the lowest average temperature on the bottom surface and the highest average temperature in the solid domain. The C-MCHS has the least thermal resistance for all Re between 100 to 500. In light of the component, the plan standards to move toward the presentation of inclination are proposed.","PeriodicalId":506830,"journal":{"name":"Theoretical and Natural Science","volume":"70 3","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-03-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140077786","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Improving liquid cancer biopsy through computer-aided microfluidic device design based on the tubular pinch effect and Deans flow 基于管状夹持效应和迪恩斯流的计算机辅助微流体设备设计改进了液体癌症活检技术

Theoretical and Natural Science Pub Date : 2024-03-07 DOI: 10.54254/2753-8818/31/20241145

Alexander Recce

{"title":"Improving liquid cancer biopsy through computer-aided microfluidic device design based on the tubular pinch effect and Deans flow","authors":"Alexander Recce","doi":"10.54254/2753-8818/31/20241145","DOIUrl":"https://doi.org/10.54254/2753-8818/31/20241145","url":null,"abstract":"A blood test, called a liquid biopsy is being developed by several research groups for the early detection of cancer. The key challenge in this process is enrichment, or isolation, of the small number of cancer cells in blood serum from other cells. This study uses numerical simulations to design devices that advance the state of art in the enrichment of circulating cancer cells. In particular, the lift forces acting on neutrally buoyant small spherical particles in a Poiseuille flow bounded by a wall are modelled using numerical computation. Specifically, we explore the influence of the Reynolds number, distance to the wall, and particle size on these lift forces, building upon previous research on the Segre-Silberberg effect. By validating the mechanism by which particles concentrate at specific positions within the fluid, we confirm the existence of the Segre-Silberberg effect in this system. Subsequently, we apply a customized 3D model of a filtration device to investigate the Segre-Silberberg effect and Deans effect in a non-Poiseuille flow, which can be applied in liquid cancer biopsy. Our results demonstrate that this flow pattern could potentially be used to separate cancer cells from the mean flow. Finally, we apply the flow separation mechanisms in microfluidic design through a rapid 3D design and computational fluid dynamics (CFD) verification cycle. The popular spiral microfluidic design does not demonstrate strong flow separation pattern in our tests, while the sinusoidal design shows much more promise. Further research is needed to empirically evaluate these designs.","PeriodicalId":506830,"journal":{"name":"Theoretical and Natural Science","volume":"12 4","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-03-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140077422","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0