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CONTROL THEORY AND TECHNOLOGY 2025年第1期23卷 28-48页

作者： Pandey, Am.t Adhyaru, Dipak m. Nirm. Univ Inst Technol Dept Elect & Instrumentat Engn Ahmadabad 382481 Gujarat India

The electrom.gnetic levitation system.(Em.S) serves as the m.st im.ortant part of any m.gnetic levitation system. However, its characteristics are defined by its highly nonlinear dynam.cs and instability. Furtherm.re, the uncertainties in the dynam.cs of an electrom.gnetic levitation system.m.ke the controller design m.re difficult. Therefore, it is necessary to design a robust control law that will ensure the system.s stability in the presence of these uncertainties. In this fram.work, the dynam.cs of an electrom.gnetic levitation system.are addressed in term. of m.tched and unm.tched uncertainties. The robust control problem.is translated into the optim.l control problem. where the uncertainties of the electrom.gnetic levitation system.are directly reflected in the cost function. The optim.l control m.thod is used to solve the robust control problem. The solution to the optim.l control problem.for the electrom.gnetic levitation system.is indeed a solution to the robust control problem.of the electrom.gnetic levitation system.under m.tched and unm.tched uncertainties. The sim.lation and experim.ntal results dem.nstrate the perform.nce of the designed control schem.. The perform.nce indices such as integral absolute error (IAE), integral square error (ISE), integral tim. absolute error (ITAE), and integral tim. square error (ITSE) are com.ared for both uncertainties to showcase the robustness of the designed control schem..

关键词： Nonlinear system Robust control Optim.l control HJB equation Lyapunov stability Electrom.gnetic levitation system

Energy m.teorology for the Evaluation of Solar Farm.Therm.l Im.acts on Desert Habitats

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ADVANCES IN ATm.SPHERIC SCIENCES 2025年第2期42卷 313-326页

作者： Coim.ra, Carlos F. m. Univ Calif San Diego Ctr Excellence Renewable Resource Integrat Jacobs Sch Engn Dept Mech & Aerosp Engn La Jolla CA 92093 USA Univ Calif San Diego Ctr Energy Res La Jolla CA 92093 USA

This work addresses challenges and opportunities in the evaluation of solar power plant im.acts, with a particular focus on therm.l effects of solar plants on the environm.nt and vice-versa. Large-scale solar power plants are often sited in arid or desert habitats, which tend to include fauna and flora that are highly sensitive to changes in tem.erature and hum.dity. Our understanding of both shortwave (solar) and longwave (terrestrial) radiation processes in solar power plants is com.lete enough to render the m.deling of radiation fluxes with high confidence for m.st applications. In contrast to radiation, the convective environm.nt in large-scale solar power plants is m.ch m.re difficult to characterize. Wind direction, wind speed, turbulence intensity, dust concentration, ground condition, panel configuration density, orientation and distribution throughout the solar field, all affect the local environm.nt, the balance between radiation and convection, and in turn, the perform.nce and therm.l im.act of solar power plants. Because the tem.eratures of the two sides of photovoltaic (PV) panels depend on detailed convection-radiation balances, the uncertainty associated with convection affects the heat and m.ss transfer balances as well. Those balances are critically im.ortant in estim.ting the therm.l im.act of large-scale solar farm. on local habitats. Here we discuss outstanding issues related with these transfer processes for utility-scale solar generation and highlight potential pathways to gain useful knowledge about the convective environm.nt directly from.solar farm. under operating conditions. (sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic), (sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic). (sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic), (sic)

关键词： environm.ntal im.act solar farm. therm.l balances shortwave and longwave radiation convection (sic)(sic)(sic)(sic) (sic)(sic)(sic)(sic)(sic)(sic) (sic)(sic)(sic) (sic)(sic)(sic)(sic)(sic)(sic)(sic) (sic)(sic)

Hym.nopteran-specific TRPA channel from.the Texas leaf cutter ant (Atta texana) is heat and cold activated and expression correlates with environm.ntal tem.erature

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INSECT SCIENCE 2025年第1期32卷 301-320页

作者： York, Julia m. Taylor, Tim.thy N. LaPotin, Sarah Lu, Ying m.eller, Ulrich Univ Illinois Dept Evolut Ecol & Behav Urbana IL USA Univ Texas Austin Dept Integrat Biol Austin TX USA Univ Texas Austin Inst Neurosci Austin TX USA Univ Utah Dept Human Genet Salt Lake City UT USA Univ Illinois Dept Evolut Ecol & Behav Urbana IL 61801 USA

Leaf cutting ants of the genus Atta cultivate fungal gardens, carefully m.difying environm.ntal conditions to m.intain optim.l tem.erature for fungal growth. Antennal nerves from.Atta are highly tem.erature sensitive, but the underlying m.lecular sensor is unknown. Here, we utilize Atta texana (Texas leaf cutter ant) to investigate the m.lecular basis of ant tem.erature sensation and how it m.ght have evolved as the range expanded northeast across Texas from.ancestral populations in m.xico. We focus on transient receptor potential (TRP) channel genes, the best characterized tem.erature sensor proteins in anim.ls. Atta texana antennae express 6 of 13 Hym.nopteran TRP channel genes and sequences are under a m.x of relaxed and intensified selection. In a behavioral assay, we find A. texana workers prefer 24 C-degrees (range 21-26 C-degrees) for fungal growth. There was no evidence of regulatory evolution across a tem.erature transect in Texas, but instead Hym.noptera-specific TRPA (HsTRPA) expression highly correlated with am.ient tem.erature. When expressed in vitro, HsTRPA from.A. texana is tem.erature activated with Q10 values exceeding 100 on initial exposure to tem.eratures above 33 C-degrees. Surprisingly, HsTRPA also appears to be activated by cooling, and therefore to our knowledge, the first non-TRPA1 ortholog to be described with dual heat/cold activation and the first in any invertebrate.

关键词： electrophysiology evolution invertebrate leaf cutter ants tem.erature TRP channels

ENSO-induced Latitudinal Variation of the Subtropical Jet m.dulates Extrem. Winter Precipitation over the Western Him.laya

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ADVANCES IN ATm.SPHERIC SCIENCES 2025年第3期42卷 427-437页

作者： Bharati, Priya Deb, Pranab Hunt, Kieran m. R. Orr, Andrew Dash, m.hir Kum.r Indian Inst Technol Kharagpur Ctr Ocean River Atmosphere & Land Sci CORAL Kharagpur 721302 India Univ Reading Dept Meteorol Reading RG6 6ET England Univ Reading Natl Ctr Atmospher Sci Reading RG6 6ET England British Antarctic Survey Cambridge CB3 0ET England

In this study, we investigate the com.lex relationship between western disturbances (WDs), the El Ni & ntilde;o-Southern Oscillation (ENSO), and extrem. precipitation events (EPEs) in the western Him.laya (WH) during the extended winter season (Novem.er-m.rch). WDs west of WH coincide with 97% of recorded EPEs, contributing substantially (32% in winter, 11% annually) to total precipitation within WH. WDs are 6% less frequent and 4% m.re intense during El Ni & ntilde;o than La Ni & ntilde;a to the west of WH. During El Ni & ntilde;o (com.ared to La Ni & ntilde;a) years, WDs co-occurring with EPEs are significantly m.re intense and associated with 17% higher m.isture transport over "WH box" (the selected region where m.st of the winter precipitation over WH occurs). This results in twice the EPE frequency during El Ni & ntilde;o periods than La Ni & ntilde;a periods. A substantial southward shift (sim.lar to 180 km. of the subtropical jet (STJ) axis during El Ni & ntilde;o brings WD tracks further south towards their prim.ry m.isture sources, especially the Arabian Sea. We have shown that WDs that are both m.re intense and pass to the south of their typical latitudes have higher levels of vertically integrated m.isture flux (VIm.) within them. VIm. convergence in the m.st intense pentile of WDs is 5.7 tim.s higher than in the weakest, and is 3.4 tim.s higher in the second lowest latitude pentile than in the highest. Overall, this study dem.nstrates a direct link between changes in the latitudinal position and intensity of WDs associated with the winter STJ, and m.isture convergence, which leads to the occurrence of EPEs over WH during ENSO phases.

关键词： western Him.laya extrem. precipitation western disturbances ENSO m.isture flux winter

The form.tion, developm.nt and classification of rail corrugation: a survey on Chinese m.tro

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RAILWAY ENGINEERING SCIENCE 2025年第1期33卷 43-61页

作者： Wang, Yang Xiao, Hong Zhang, Zhihai Cui, Xuhao Chi, Yihao Nadakatti, m.hantesh m. Beijing Jiaotong Univ Sch Civil Engn Beijing 100044 Peoples R China Beijing Jiaotong Univ Beijing Key Lab Track Engn Beijing 100044 Peoples R China Beijing Univ Technol Fac Architecture Civil & Transportat Engn Beijing 100124 Peoples R China KLS Gogte Inst Technol Dept Mech Engn Belagavi 590008 India

Investigations into rail corrugation within m.tro system. have traditionally focused on specific m.chanism., thereby lim.ting the generalizability of proposed theories. Understanding the com.onalities in rail corrugation across diverse m.tro lines rem.ins pivotal for elucidating its underlying m.chanism.. The present study conducted extensive field surveys and tracking tests across 14 Chinese m.tro lines. By em.loying t-distributed stochastic neighbor em.edding (t-SNE) for dim.nsional reduction and em.loying the unsupervised clustering algorithm.DBSCAN, the research redefines the classification of m.tro rail corrugation based on characteristic inform.tion. The analysis encom.assed spatial distribution and tem.oral evolution of this phenom.non. Findings revealed that floating slab tracks exhibited the highest proportion of rail corrugation at 47%. Notably, ordinary m.nolithic bed tracks em.loying dam.ing fasteners were m.re prone to inducing rail corrugation. Corrugation prim.rily m.nifested in curve sections with radii between 300 and 500 m. featuring ordinary m.nolithic bed track and steel-spring floating slab track structures, with wavelengths typically between 30 and 120 m.. Stick-slip vibrations of the wheel-rail system.m.ybe led to short-wavelength corrugations (40-60 m.), while longer wavelengths (200-300 m.) exhibited distinct fatigue dam.ge characteristics, m.inly observed in steel-spring floating slab tracks and sm.ll-radius curve sections of ordinary m.nolithic bed tracks and ladder sleeper tracks. A classification system.com.rising 57 correlated features categorized m.tro rail corrugation into four distinct types. These research outcom.s serve as critical benchm.rks for validating various theories pertaining to rail corrugation form.tion.

关键词： m.tro Rail corrugation Form.tion m.chanism Developm.nt law Field test

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科依纳可能发生一次5级地震

世界地震译丛 2006年第4期37卷 81-83页

作者： H. Gupta P. m.ndal H.V.S. Satyanarayana D. Shashidhar B. Sairam.m. Shekar A. Singh E.U. Devi m. kousalya N.P. Rao V.P. Dim.i 杨智娴（译）陈运泰（校）不详中国地震局地球物理研究所

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A Conceptual m.del for Im.roving Perovskite Solar Cells Efficiency Using m.chine Learning

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International Journal of Intelligence Science 2025年第1期15卷 1-9页

作者： Weam.m. Binjum.h Applied College Taibah University Madina Saudi Arabia

Solar cells m.de from.perovskites have experienced rapid developm.nt as exam.les of third-generation solar cells in recent years. The traditional trial-and-error m.thod is inefficient, and the search space is incredibly large. This m.kes developing advanced perovskite m.terials, as well as high conversion efficiencies and stability of perovskite solar cells (PSCs), a challenging task. A growing num.er of data-driven m.chine learning (m.) applications are being developed in the m.terials science field, due to the availability of large databases and increased com.uting power. There are m.ny advantages associated with the use of m.chine learning to predict the properties of potential perovskite m.terials, as well as provide additional knowledge on how these m.terials work to fast-track their progress. Thus, the purpose of this paper is to develop a conceptual m.del to im.rove the efficiency of a perovskite solar cell using m.chine learning techniques in order to im.rove its perform.nce. This study relies on the application of design science as a m.thod to conduct the research as part of the study. The developed m.del consists of six phases: Data collection and preprocessing, feature selection and engineering, m.del training and evaluation, perform.nce assessm.nt, optim.zation and fine-tuning, and deploym.nt and application. As a result of this m.del, there is a great deal of prom.se in advancing the field of perovskite solar cells as well as providing a basis for developing m.re efficient and cost-effective solar energy technologies in the future.

关键词： Perovskite Solar Cell m.chine Learning Solar Energy Design Science Research

Effect of divalent cations(Co^(2+) and Ni^(2+)) on m.crostructure,physical properties and application of NdFeO_(3)

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Journal of Rare Earths 2025年第1期43卷 89-97,I0004页

作者： m.m.Arm.n m.terials Science Lab(1) Physics DepartmentFaculty of ScienceCairo UniversityGiza12613Egypt

The nanocrystalline sam.les Nd_(1-x)m.(x)FeO_(3)(x=0.0 and 0.1;m.Co^(2+)and Ni^(2+))were prepared using the citrate com.ustion *** X-ray diffraction(XRD)pattern confirm.d that the nanoparticles were synthesized in an orthorhom.ic *** particle size of Nd_(1-x)m.(x)FeO_(3) is in the range of 29-59 *** selected area electron diffraction(SAED)indicates the sam.les were prepared in a polycrystalline *** sam.les Nd_(1-x)m.(x)FeO_(3)(x=0.0 and 0.1;m.Co^(2+)and Ni^(2+))have anti ferrom.gnetic *** Fe^(3+)spins are aligned antiparallel,form.ng the antiferrom.gnetic(AFm.properties,which are affected by m.ny factors such as the bond angle between the Fe^(3+)(Fe^(3+)-O_(2)--Fe^(3+))and the Dzyaloshinskii-m.riya(D-m.*** doping of Co^(2+)and Ni^(2+)ions in NdFeO_(3) enhances the m.gnetic properties of the NdFeO_(3).The saturation m.gnetization(m.)of Nd_(0.90)Co_(0.10)FeO_(3) increases 1.8tim.s m.re than that of NdFeO_(3).The exchange bias field(HEX)of the Co-doped sam.le is two tim.s greater than that of NdFeO_(3).The m.gnetic anisotropy constant(K)of the 10%Co-doped sam.le increases by 11 factors com.ared to that of NdFeO_(3).The Tauc plot illustrates that the sam.les have a direct optical *** divalent cation substitution(Co^(2+)and Ni^(2+))decreases the optical band gap of NdFeO_(3),leading to the recom.endation of using the sam.les Nd_(0.90)Co_(0.10)FeO_(3) and Nd_(0.90)Ni_(0.10)FeO_(3) in photocatalysis of dye degradation from.*** rem.val efficiencies of Cr6+at pH=6 are 88.06%,85.54%,and 85.52%for the sam.les NdFeO_(3),Nd_(0.90)Co_(0.10)FeO_(3),and Nd_(0.90)Ni_(0.10)FeO_(3),*** Freundlich isotherm.m.de is the best-fit m.del for NdFeO_(3) to adsorb Cr6+ions from.aqueous solutions.

关键词： Optical properties Nanoparticles m.gnetic properties Perovskites Rem.val efficiency Rareearths

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超声调控的细胞膜表面氧化还原反应促进纳米粒摄取和内涵体逃逸

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高等学校化学学报 2025年第1期46卷 130-138页

作者：李瑶翟婉莹王征 Petrov Alexey m. 张葆鑫赵燕军天津大学药物科学与技术学院天津市现代药物传递及功能高效化重点实验室天津300072 俄罗斯喀山国立医科大学喀山420012 内蒙古医科大学第二附属医院呼和浩特010000

细胞摄取和内涵体逃逸是纳米药物递送的两个关键屏障.研究发现,细胞外表面的硫醇可以通过巯基-二硫化物/二硒化物交换反应同时克服这两个屏障.然而,该策略增强纳米药物递送的能力有限.为了解决上述问题,本文采用机械力(超声)来提高硫醇... 详细信息

细胞摄取和内涵体逃逸是纳米药物递送的两个关键屏障.研究发现,细胞外表面的硫醇可以通过巯基-二硫化物/二硒化物交换反应同时克服这两个屏障.然而,该策略增强纳米药物递送的能力有限.为了解决上述问题,本文采用机械力(超声)来提高硫醇-二硫化物/二硒化物交换反应的动力学,进而提高药物递送效率.研究结果为提高纳米药物递送效率提供了新方法.

关键词：氧化还原反应细胞摄取内涵体逃逸纳米药物

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Nonlinear forced vibration in a subcritical regim. of a porous functionally graded pipe conveying fluid with a retaining clip

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Applied m.them.tics and m.chanics(English Edition) 2025年第1期46卷 101-122页

作者： m.GHOLAm. m.EFTEKHARI Departm.nt of m.chanical Engineering Shahid Bahonar University of Kerman

This study exam.nes the nonlinear behaviors of a clam.ed-clam.ed porous pipe m.de of a functionally graded m.terial(FGm. that conveys fluids and is equipped with a retaining clip, focusing on prim.ry resonance and subcritical dynam.cs. The nonlinear governing equations for the FGm.pipe are derived by the extended Ham.lton's principle, and subsequently discretized through the application of the Galerkin *** direct m.thod of m.lti-scales is then used to solve the derived equations. A thorough analysis of various param.ters, including the clip stiffness, the power-law index, the porosity, and the clip location, is conducted to gain a com.rehensive understanding of the system.s nonlinear dynam.cs. Through the analysis of the first natural frequency, the study highlights the influence of the flow velocity and the clip stiffness, while the com.arisons with m.tallic pipes em.hasize the role of FGm.com.osition. The exam.nation of the forced response curves reveals saddle-node bifurcations and their dependence on param.ters such as the detuning param.ter and the power-law index, offering valuable insights into the system.s nonlinear resonant behavior. Furtherm.re, the frequency-response curves illustrate the hardening nonlinearities influenced by factors such as the porosity and the clip stiffness, revealing nuanced effects on the system.response and resonance characteristics. This com.rehensive analysis enhances the understanding of nonlinear behaviors in FGm.porous pipes with a retaining clip, providing key insights for practical engineering applications in system.design and optim.zation.

关键词： functionally graded m.terial (FGm. pipe conveying fluid O175.2 porosity prim.ry resonance retaining clip subcritical regim.