STUDY ON WARM FORMING LIMIT PREDICTION OF ADVANCED HIGH STRENGTH STEEL DP780 SHEET METAL by WANG KaiDi, LI Di, LENG YangSong, FU QiuTao, XU JiaChuan, JIANG Ning

“…Thus a model for predicting tensile fracture and shear fracture of DP780 steel under different strain paths was developed,by combining it with the warm forming constitutive model and the Hill ’48 yield criterion,the finite element simulation of the rigid mold bulging test was realized,and the forming limit curve of DP780 steel sheet at the temperature of 673 K was predicted,The mathematical model of forming limit was established. The results show that the forming limit results predicted by this method have better precision.…”
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A SYSTEM DYNAMICS MODEL TO DETERMINE THE VALUE OF INVENTORY HOLDING COST by BABATUNDE OMONIYI ODEDAIRO, EMILOLA HELEN ALABA, INYENEOBONG EDEM

“…Giving considerations to this reality, a mathematical model to determine the value of IHC using systems dynamics approach was developed. …”
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The Piston Ring-Cylinder Bore Interface Leakage of Bent-Axis Piston Pumps Based on Elastohydrodynamic Lubrication and Rotation Speed by Lvjun Qing, Lichen Gu, Yan Wang, Wei Xue, Zhufeng Lei

“…First, the proposed model includes a minimum film thickness model of PRCB to analyze the dynamic change of oil film of PRCB when subject to the elastohydrodynamic lubrication. After that, a mathematical model of PRCB is induced by combining the minimum film thickness model with the flow equation, which helps produce the effects of the oil film on the leakage of PRCB. …”
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Statistical Distribution of Urban Area Reveals a Converging Trend of Global Urban Land Expansion by Shengjie Hu, Zhenlei Yang, Sergio Andres Galindo Torres, Zipeng Wang, Haoying Han, Yoshihide Wada, Thomas Cherico Wanger, Ling Li

“…This trend is well captured by a unified mathematical model based on the shifted power law distribution function and is reflected in the gradual predominance of medium‐size cities over small‐size cities in the configuration of urban systems across the world. …”
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Numerical investigation of coal pillar damage mechanisms for various width-to-height ratios by Xuanhui Wang, Ze Xia, Qiangling Yao, Xuehua Li, Qiang Xu, Liu Zhu

“…In order to analyze the features of dynamical evolution of vertical stress distribution and failure zone during loading, a meticulously validated roof–coal–floor composite mathematical model was established.The energy evolution for coal pillars under diverse w/h ratios was analyzed, and the failure energy ratio and elastic strain energy release rate were introduced to evaluate the failure severity. …”
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LOCAL VALUES OF HEAT TRANSFER PARAMETERS ON THE INTERIOR SURFACES OF THE BUILDING ENVELOPE by A. E. Zakharevich

“…The developed two-dimensional physical and mathematical model takes into account the complex conjugated heat transfer in the building envelopes and indoor free spaces, the influence of heater type on the transfer processes. …”
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Reagent efficiency and analytical sensitivity optimization for a reliable SARS-CoV-2 pool-based testing strategy by José P. Miranda, Javiera Osorio, Marcia Silva, Carola Silva, Victoria Madrid, Rossana Camponovo, Marcela Henríquez-Henríquez

“…Methods: We developed a mathematical model to determine the pooling conditions that maximize reagent efficiency and analytical sensitivity. …”
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Designing a Dynamic and Sustainable Cellular Manufacturing System by Considering the Amount of Energy Consumption and Manpower in Production Planning by Nader Ghanei, Gholam Reza Esmaeilian, Amir Saman Kheirkhah

“…In this article, a new multi-objective mathematical model for creating a sustainable cellular Manufacturing system is presented according to the mentioned items in order to minimize the production costs in the system in addition to optimizing the environmental effects of the Manufacturing system. …”
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UNSTABLE CRITICAL EQUILIBRIUM IN THE DYNAMICS OF COMPLEX STRUCTURED POPULATION OF STURGEON by V. A. Dubrovskaya, T. N. Solovieva, A. Yu. Perevaryukha

“…Informative, that the Volga stellate sturgeon Acipencer stellatus observed some form of non-linearity in the efficiency of spawning and require a different kind of fish-specific mathematical model.…”
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THE PROBLEM OF CORRUPTION OF BASIC SCIENTIFIC INVESTIGATIONS IN PARTICULAR: FORMAL-ETHIC AND ECONOMIC ASPECTS by V. O. Lobovikov

“…The methods involve the historical-philosophical and logical-linguistic analysis of texts; creation and studying of the elementary discrete mathematical model of the researched moral phenomenon at the level of artificial language of two-digit algebra of the natural right and morals; use of such conceptual and figurative tool of the economic theory as Boston Chart.Results and scientific novelty. …”
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Multi-Scale Robotics: A Numerical Investigation on Mobile Micro-Tweezers for Micro-Manipulation with Extreme Requirements by Ahmet Fatih Tabak

“…Here, a comprehensive mathematical model is presented to reflect on the dynamics of such micro-tweezer systems. …”
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A model of optimal dosing of antibiotic treatment in biofilm by Mudassar Imran, Hal L. Smith

“…Biofilm formation is theprimary cause of several persistent infections found in humans. Wederive a mathematical model of biofilm and surrounding fluiddynamics to investigate the effect of a periodic dose of antibioticon elimination of microbial population from biofilm. …”
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Voltage Stability Analysis of Front-End Speed Controlled Wind Turbine Integrated into Regional Power Grid Based on Bifurcation Theory by Kaide Ren, Hongwei Li, Shuaibing Li, Haiying Dong

“…Firstly, differential-algebraic equations (DAEs) describing the dynamic characteristics of the wind turbine are given and the mathematical model of the system includes FSCWT is established. …”
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Managing the Investment Attractiveness of the Federal Subjects of Russia in the Context of the UN Sustainable Development Goals by A. N. Borisov, A. I. Borodin, R. V. Gubarev, E. I. Dzyuba, E. R. Sagatgareev

“…Inter-regional gaps in the investment sphere and sanction pressure on the national economy have actualized the issue of improving the efficiency of managing investment attractiveness at the mesoscale using modern high-precision methods of economic and mathematical modeling. A number of well-known thematic ratings are used to assess the investment attractiveness of the Russian regions, whose critical analysis made it possible to identify their main shortcomings. …”
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Research Progress and Prospect of Extreme Water Increase by Storm Surge in Estuaries — A Case Study of Guangdong-Hong Kong-Macao Greater Bay Area by LIU Yuexuan, LI Huijing, LI Lanbin, LIU Xiaojian

“…Significant increases in water and extreme tide levels caused by typhoon storm surges are the primary threat to flood safety in estuarine areas,and are also the main cause of major natural disaster losses in the Guangdong-Hong Kong-Macao Greater Bay Area in recent years.This paper reveals the evolution patterns of water increase in storm surges over the years and introduces corresponding research methods.Meanwhile,it systematically reviews research achievements on the formation mechanism of extreme tide levels in storm surges from both foreign and domestic perspectives.Combined calculation models of extreme tide levels formed by astronomical tides and storm surges in China and abroad are also summarized,with a focus on achievements in dynamic mechanisms during extreme water increase in storm surges.Additionally,a two-dimensional nested mathematical model of storm surges in the South China Sea and the Pearl River Estuary is built,and the most unfavorable typhoon intensity and path are designed.The maximum water increase distribution in the Guangdong-Hong Kong-Macao Greater Bay Area is preliminarily simulated and obtained.Finally,it is urgent to put forward a set of safe,concise,and applicable formula for calculating the extreme tide levels of storm surges as soon as possible based on the understanding of the physical mechanism of the interaction between astronomical tides and storm surges.…”
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Influences of Hydrodynamic Forces on the Identification of the Rotor-Stator-Rubbing Fault in a Rotating Machinery by Bernard Xavier Tchomeni, Desejo Filipeson Sozinando, Alfayo Alugongo

“…The simplified mathematical model of the rotor-stator system is established based on the energy principle. …”
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Analysis of Drag Torque Characteristic of Hydro-viscous Clutch with Consideration of Cavitation Effect by Sun Chunlian

“…In order to accurately predict the internal flow field and drag torque characteristics of the hydro-viscous clutch,with the flow field of double circular groove clearance as the research object,based on the principle of hydrodynamics and the Newtonian internal friction law,a two-phase flow CFD mathematical model considering cavitation effect is established,the fluid field is numerically simulated by FLUENT,and the influence of different rotational speed,inlet pressure and film thickness on field distribution,pressure distribution and drag torque characteristics are studied. …”
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Research on design and control method of active vibration isolation system based on piezoelectric Stewart platform by Zhiyi Fang, Zhiliang Yu, Qingping Huang, Yanfen Wang, Xingsheng Gu

“…Next, given the inherent hysteretic nonlinearity of piezoelectric ceramics, which significantly affects positioning accuracy, the hysteresis mechanism of the actuators is analyzed, and a phenomenological mathematical model based on Bouc–Wen operators is established. …”
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Damping Torque Analysis of the PMSG-Based WT with Supplementary Damping Control for Mitigating Interarea Oscillations by Yanan Yang, Yujun Li, Xiaotian Yuan, Jiapeng Li, Zhengchun Du

“…This study presents a comprehensive analysis of the impact that a supplementary damping controller of the permanent magnet synchronous generator (PMSG)-based wind turbine (WT) has on low-frequency oscillation (LFO) damping. A reduced mathematical model of an interarea system is first established. …”
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Synthesis and Empirical Analysis of the Thermophysical Characteristics of GO-Ag Aqueous Hybrid Nanofluid Using Environmentally Friendly Reducing and Stabilizing Agents by M. Armstrong, M. Sivasubramanian, N. Selvapalam, R. Pavitra, P. Rajesh Kanna, Haiter Lenin

“….% exhibited the most significant enhancement in thermal conductivity, with improvements of 15.22% at 293 K and 31.19% at 333 K compared to the base fluid. A mathematical model was developed based on the thermal conductivity experimental results using the response surface methodology (RSM). …”
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