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Improving Smart Agriculture Through the Use of Machine Learning to Offer Tailored Crop Forecasts

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Remote Sensing in Earth Systems Sciences 2024年第1期8卷 74-83页

作者： Patil, R.N. Maroor, Jnaneshwar Pai Dhanke, Jyoti A. Chunduru, Madhava Rao Singh, Mangal Jangir, Pradeep Upadhyay, Shrikant Department of Mechanical Engineering Bharati Vidyapeeth’s College of Engineering Lavale Pune India Department of Business Administration Nitte Institute of Professional Education Nitte (Deemed to Be University) Karnataka Mangaluru India Department of Engineering Science (Mathematics) Bharati Vidyapeeth’s College of Engineering Lavale Pune India Department Of Computer Science And Engineering Koneru Lakshmaiah Educational Foundation Vaddeswaram AP Guntur District India Department of Electronics and Telecommunication Engg. Symbiosis Institute of Technology Pune Campus Symbiosis International (Deemed University) Pune India Department of Biosciences Saveetha School of Engineering Saveetha Institute of Medical and Technical Sciences Chennai India Hourani Center for Applied Scientific Research Al-Ahliyya Amman University Amman 19328 Jordan Department of Electronics and Communication Engineering MLR Institute of Technology Hyderabad India

It is not possible to identify crop illnesses by examining each disease independently. Users may only get forecasts for the most anticipated illnesses with the use of a robust analytic methodology. This study presents a method that can collect, analyze, and identify crop health information all on one platform using an IoT and machine learning-based approach. Food security and the provision of essential raw materials for several industries are both supported by agriculture, which is the most important and basic vocation. Improved crop yields, thanks to new innovative agricultural practices, mean less water wasted and more money in the bank. An intelligent irrigation system that uses a machine learning algorithm to forecast a crop’s water needs is the suggested model. One such rapidly evolving invention is the Internet of Things (IoT), which is now spreading its wings across all geographies. Technological innovation is reaching a new level of practicality in agriculture with the rise of embedded PCs like Arduino. Soil quality monitoring using Arduino, several sensors, and an Android app is shown and accomplished in this study. Temperature, soil moisture level, ammonia, and carbon content limit soil quality in this study. Arduino is used as both a worker and an information processing device, and it is in charge of sensor security. The terminal device is an Android phone. Producers may improve agricultural yields by collecting and analyzing data on weather, soil, seed, and yields of crops, moisture, and gusts of wind in specific areas. Furthermore, a flask-built GUI was used to present crop forecasts derived from a bespoke recommender system. Because of its adaptable design, the system may one day be able to discover the suggested items of other areas. This article uses targeted agricultural data to create five machine-learning approaches that are comparable to one another and to compare and contrast them. © The Author(s), under exclusive licence to Springer Nature Swit

关键词： Decision navigation systems Internet of Things (IoT) Irrigation systems Machine learning algorithms Sensors

Critical latitude in global quasi-geostrophic flow on a rotating sphere

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arXiv 2024年

作者： Franken, Arnout D. Luesink, Erwin Ephrati, Sagy R. Geurts, Bernard J. Mathematics of Multiscale Modelling and Simulation Department of Applied Mathematics Faculty EEMCS University of Twente PO Box 217 Enschede7500 AE Netherlands Korteweg-de-Vries Institute University of Amsterdam PO Box 94248 Science Park 107 Amsterdam1090 GE Netherlands Department of Mathematical Sciences Chalmers University of Technology Gothenburg412 96 Sweden Multiscale Physics Center for Computational Energy Research Department of Applied Physics Eindhoven University of Technology Eindhoven Netherlands

In this paper, we study geostrophic turbulence without external forcing or dissipation, using a Casimir-preserving numerical method. The research examines the formation of large zonal jets, common in geophysical flows, especially in giant gas planets. These jets form due to the east-west stretching of vortices, influenced by the gradient of the Coriolis parameter, leading to a critical latitude beyond which jets do not form. Using a global quasi-geostrophic model with a fully latitude-dependent Coriolis parameter, we investigate this critical latitude, which is theorized to depend only on the product of the Rossby number and the Lamb parameter. By simulating random flow fields, the critical latitude was identified through zonally averaged zonal velocity profiles. Results align with geostrophic theory, especially near typical Rossby and Lamb parameter values for Earth’s atmosphere. However, in the regime of weak rotation (high Rossby numbers) and strong stratification (high Lamb values), no clear critical latitude emerges;instead, zonal jet amplitude and width decrease gradually towards the poles. This research paves the way for further study of jet dynamics under a fully latitude-dependent Coriolis parameter. Copyright © 2024, The Authors. All rights reserved.

关键词： Miocene

Casimir preserving numerical method for global multilayer geostrophic turbulence

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arXiv 2024年

Accurate long-term predictions of large-scale flow features on planets are crucial for understanding global atmospheric and oceanic systems, necessitating the development of numerical methods that can preserve essential physical structures over extended simulation periods without excessive computational costs. Recent advancements in the study of global single-layer barotropic models have led to novel numerical methods based on Lie-Poisson discretization that preserve energy, enstrophy and higher-order moments of potential vorticity. This work extends this approach to more complex stratified quasi-geostrophic (QG) systems on the sphere. In this work, we present a formulation of the multi-layer QG equations on the full globe. This allows for extending the Lie-Poisson discretization to multi-layer QG models, ensuring consistency with the underlying structure and enabling long-term simulations without additional regularization. The numerical method is benchmarked through simulations of forced geostrophic turbulence and the long-term behaviour of unforced multi-layered systems. These results demonstrate the structure-preserving properties and robustness of the proposed numerical method, paving the way for a better understanding of the role of high-order conserved quantities in large-scale geophysical flow dynamics. Copyright © 2024, The Authors. All rights reserved.

关键词： Atmospheric movements

Interacting models for twisted bilayer graphene: A quantum chemistry approach

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Physical Review B 2023年第23期107卷 235123-235123页

作者： Fabian M. Faulstich Kevin D. Stubbs Qinyi Zhu Tomohiro Soejima Rohit Dilip Huanchen Zhai Raehyun Kim Michael P. Zaletel Garnet Kin-Lic Chan Lin Lin Department of Mathematics University of California Berkeley California 94720 USA Department of Physics University of California Berkeley California 94720 USA Division of Engineering and Applied Science California Institute of Technology Pasadena California 91125 United States Division of Chemistry and Chemical Engineering California Institute of Technology Pasadena California 91125 USA Materials Science Division Lawrence Berkeley National Laboratory Berkeley California 94720 USA Applied Mathematics and Computational Research Division Lawrence Berkeley National Laboratory Berkeley California 94720 USA

The nature of correlated states in twisted bilayer graphene (TBG) at the magic angle has received intense attention in recent years. We present a numerical study of an interacting Bistritzer-MacDonald (IBM) model of TBG using a suite of methods in quantum chemistry, including Hartree-Fock, coupled cluster singles, doubles (CCSD), and perturbative triples [CCSD(T)], as well as a quantum chemistry formulation of the density matrix renormalization group method (DMRG). Our treatment of TBG is agnostic to gauge choices, and hence we present a new gauge-invariant formulation to detect the spontaneous symmetry breaking in interacting models. To benchmark our approach, we focus on a simplified spinless, valleyless IBM model. At integer filling (ν=0), all numerical methods agree in terms of energy and C2zT symmetry breaking. Additionally, as part of our benchmarking, we explore the impact of different schemes for removing “double-counting” in the IBM model. Our results at integer filling suggest that cross validation of different IBM models may be needed for future studies of the TBG system. After benchmarking our approach at integer filling, we perform the first systematic study of the IBM model near integer filling (for |ν|<0.2). In this regime, we find that the ground state can be in a metallic and C2zT symmetry breaking phase. The ground state appears to have low entropy, and therefore can be relatively well approximated by a single Slater determinant. Furthermore, we observe many low entropy states with energies very close to the ground-state energy in the near integer filling regime.

关键词： Electronic structure First-principles calculations Bilayer graphene Twisted bilayer graphene Approximation methods for many-body systems Electron-correlation calculations Many-body techniques Mean field theory Quantum chemistry methods Second quantization Symmetries

Uniqueness for Some Mixed Problems of Nonlinear Elastostatics

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arXiv 2025年

作者： Rosakis, Phoebus Department of Mathematics and Applied Mathematics University of Crete Crete Heraklion70013 Greece Institute for Applied and Computational Mathematics Foundation of Research and Technology-Hellas Crete Heraklion70013 Greece Center of Mediocrity for Antiquated Materials Mitato Crete72300 Greece

We show that certain mixed displacement/traction problems (including live pressure tractions) of nonlinear elastostatics that are solved by a homogeneous deformation, admit no other classical equilibrium solution under suitable constitutive inequalities and domain boundary restrictions. This extends a well known theorem of Knops and Stuart on the pure displacement problem. © 2025, CC BY.

关键词： Digital arithmetic

Thermoelastic properties and thermal evolution of the Martian core from ab initio calculated ferromagnetic Fe-S liquid

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arXiv 2023年

作者： Li, Wei-Jie Li, Zi Ma, Zhe Zhou, Jie Wang, Cong Zhang, Ping Intelligent Science & Technology Academy Limited of CASIC Beijing100141 China Institute of Applied Physics and Computational Mathematics Beijing100088 China Scientific Research Key Laboratory of Aerospace Defence Intelligent Systems and Technology Beijing100141 China Tianfu Innovation Energy Establishment Chengdu610213 China Center for Applied Physics and Technology Peking University Beijing100871 China

The accurate thermoelastic properties and thermal conductivity are crucial in understanding the thermal evolution of the Martian core. A fitting method based on the ab initio calculated pressure-volume-temperature data is proposed in the formulation of the equation of state with high accuracy, by which the pressure and temperature dependent thermoelastic properties can be directly calculated by definitions. The ab initio results show that the liquid Fe0.75S0.25 under Martian core condition is thoroughly in the ferromagnetic state, without existing spin crossover. The liquid Fe0.75S0.25 in magnetic calculation owns a low thermal conductivity (21~23 W/m/K) when compared with non-magnetic calculation at the same state. Based on the Insight estimated and ab initio calculated properties of the Martian core, the iron snow model is verified when the current temperature at the core-mantle boundary is below the core melting temperature, and the simply secular cooling model is verified on the contrary. © 2023, CC BY.

关键词： Thermal conductivity

Quantum correction to the anomalous Hall effect in PtMnGe thin films

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Physical Review B 2023年第22期107卷 224409-224409页

作者： K. K. Meng J. K. Chen Y. Wu X. G. Xu T. Kikkawa L. P. Sun D. Z. Hou Q. Li N. N. Zhang Z. G. Fu T. Zhu Y. Jiang E. Saitoh School of Materials Science and Engineering University of Science and Technology Beijing Beijing 100083 China Department of Applied Physics The University of Tokyo Tokyo 113-8656 Japan School of Science Beijing University of Civil Engineering and Architecture Beijing 100044 China Hefei National Research Center for Physical Sciences at the Microscale University of Science and Technology of China Hefei 230026 China Institute of Applied Physics and Computational Mathematics Beijing 100094 China The Institute of Physics Chinese Academy of Sciences Beijing 100190 China

The role of quantum correction such as weak localization in anomalous Hall effects (AHEs) is an important issue. In this work, we have investigated the robust quantum correction to the AHE in magnetic PtMnGe (PMG) thin films of high crystalline quality. The PMG films have not shown long-range magnetic order. The observed temperature and magnetic field dependence of the sheet conductivities in the ultrathin PMG films are explained based on the perturbation theory, where the interplay of spin-dependent scattering and the spin Zeeman splitting effect are taken into consideration. It is found that, as long as the magnetic scattering time is comparable to the spin-orbit scattering time, the conductivity correction due to the Cooperons between antiparallel spins that involves spin-flip scattering can be negligible in the two dimensions. Therefore, even when the spin-dependent scattering exists, the quantum correction to the transport behavior is robust in the two-dimensional PMG system. Our work makes a significant step toward clarifying the role of quantum correction in the AHE of the magnetic materials.

关键词： Anomalous Hall effect Quantum interference effects Weak localization Ultrathin films Neutron reflectometry X-ray magnetic circular dichroism X-ray magnetic linear dichroism

The Anisotropic Gaussian Semi-Classical Schrödinger Propagator

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arXiv 2021年

作者： Karageorge, Panos D. Makrakis, George N. Department of Mathematics and Applied Mathematics University of Crete Voutes Campus Heraklion700 13 Greece Institute of Applied and Computational Mathematics Foundation for Research and Technology 100 Nikolaou Plastira St Vassilika Vouton Heraklion700 13 Greece

We present a construction of the Anisotropic Gaussian Semi-Classical Schrödinger Propagator, emblematic of a class of Fourier Integral Operators of quadratic phase kernels related to the Schrödinger equation. We deduce a set of algebraic relations of the variational matrices, solutions of the variational system pertaining to single Gaussian wave packet semi-classical time evolution, representing the symplectic and other invariances of the dynamics, which are subsequently used to derive the Van Vleck formula from the semi-classical propagator, as an argument for the practical importance of the later relations in the relevant wave packet calculus. © 2021, CC BY-NC-ND.

关键词： Riccati equations

An improved model of damage depth of shock-melted metal in microspall under triangular wave loading

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Chinese Physics B 2021年第9期30卷 412-418页

作者： Wen-Bin Liu An-Min He Kun Wang Jian-Ting Xin Jian-Li Shao Nan-Sheng Liu Pei Wang Department of Modern Mechanics University of Science and Technology of ChinaHefei 230027China Institute of Applied Physics and Computational Mathematics Beijing 100094China Graduate School of China Academy of Engineering Physics Beijing 100088China College of Materials Science and Engineering Hunan UniversityChangsha 410082China Science and Technology on Plasma Physics Laboratory Research Center of Laser FusionChina Academy of Engineering PhysicsMianyang 621900China State Key Laboratory of Explosion Science and Technology Beijing Institute of TechnologyBeijing 100081China Center for Applied Physics and Technology Peking UniversityBeijing 100871China

Damage depth is an important dynamic parameter for describing the degree of material damage and is also a key fundamental issue in the field of impact compression *** present work is dedicated to the damage depth of shock-melted metal in microspall under triangular wave loading,and an improved model of damage depth considering the material's compressibility and relative movement is *** damage depth obtained from the proposed model is in good agreement with the laser-driven shock loading *** with the previous model,the proposed model can predict the damage depth of shock-melted metal in microspall more ***,two-groups of the smoothed particle hydrodynamics(SPH)simulations are carried out to investigate the effects of peak stress and decay length of the incident triangular wave on the damage depth,*** the decay length increases,the damage depth increases *** the peak stress increases,the damage depth increases nonlinearly,and the increase in damage depth gradually slows *** results of the SPH simulations adequately reproduce the results of the proposed model in terms of the damage ***,it is found that the threshold stress criterion can reflect the macroscopic characteristics of microspall of melted metal.

关键词： damage depth theoretical modeling microspall triangular wave