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Mathematical modelling of ball and plate system with experimental and correlation function-based model validation

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Control theory and technology 2024年第2期22卷 326-341页

作者： t.R.Dil Kumar S.J.Mija Department of Electrical Engineering National Institute of Technology CalicutKozhikode673601KeralaIndia

the ball and plate system is an inherently nonlinear under actuated benchmark system used for validating the performance of various control schemes. A mathematical model depicting the dynamics close to that of the system is very much required for such a test bed. In this correspondence, the complete nonlinear model, a simplified nonlinear model, and a linearized model of the ball and plate system are developed. the system comprises a ball and plate mechanism and a rotary servo unit. the ball and plate mechanism is modelled using the Euler–Lagrange method, whereas the rotary servo subsystem is modelled from the first principles. the nonlinear model of the combined system is developed by including the dynamics of the servo motor with gear and rolling resistance between the ball and the plate. the simplified nonlinear model of the system is obtained with suitable assumptions. the model is linearized around the operating point using the Jacobian. the validity of the developed models is investigated through correlation function analysis. the open-loop response of the three models, viz., nonlinear, simplified nonlinear, and linearized models, is analyzed in the MAtLAB/Simulink platform. Since the open-loop system is unstable, the experimental validation of the model is performed with a double-loop PSO (particle swarm optimization) PID control scheme.

关键词： Ball and plate system Correlation function Model validation Particle swarm optimization(PSO) PSO PID controller

Evaluation of slope stability through rock mass classification and kinematic analysis of some major slopes along NH-1A from Ramban to Banihal, North Western Himalayas

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Journal of Rock Mechanics and Geotechnical Engineering 2024年第1期16卷 167-182页

作者： Amit Jaiswal A.K.Verma t.N.Singh Department of Civil and Environmental Engineering Indian Institute of Technology PatnaPatna801106India

the network of Himalayan roadways and highways connects some remote regions of valleys or hill slopes,which is vital for India’s socio-economic *** to natural and artificial factors,frequency of slope instabilities along the networks has been increasing over last few *** of stability of natural and artificial slopes due to construction of these connecting road networks is significant in safely executing these roads throughout the *** rock mass classification methods are generally used to assess the strength and deformability of rock *** study assesses slope stability along the NH-1A of Ramban district of North Western *** structurally and non-structurally controlled rock mass classification systems have been applied to assess the stability conditions of 14 *** evaluating the stability of these slopes,kinematic analysis was performed along with geological strength index(GSI),rock mass rating(RMR),continuous slope mass rating(CoSMR),slope mass rating(SMR),and Q-slope in the present *** SMR gives three slopes as completely unstable while CoSMR suggests four slopes as completely *** stability of all slopes was also analyzed using a design chart under dynamic and static conditions by slope stability rating(SSR)for the factor of safety(FoS)of 1.2 and 1 respectively.Q-slope with probability of failure(PoF)1%gives two slopes as stable *** slope angle has been determined based on the Q-slope safe angle equation and SSR design chart based on the *** value ranges given by different empirical classifications were RMR(37-74),GSI(27.3-58.5),SMR(11-59),and CoSMR(3.39-74.56).Good relationship was found among RMR&SSR and RMR&GSI with correlation coefficient(R 2)value of 0.815 and 0.6866,***,a comparative stability of all these slopes based on the above classification has been performed to identify the most critical slope along this road.

关键词： Rock mass classification Kinematic analysis Slope stability Himalayan road Static and dynamic conditions

Effect of Silicon Amendment on Growth and Nitrogen Status of Common Landscaping Plants

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American Journal of Plant Sciences 2024年第8期15卷 603-616页

作者： Bárbara Nogueira Souza Costa Milagros Ninoska Munoz Salas Kylie gil Amir Ali Khoddamzadeh Department of Earth and Environment Institute of Environment Florida International University Miami FL USA

Agriculture and natural vegetations in South Florida face with significant environmental threats such as heat and saltwater intrusion. this study aimed to investigate how silicon application could improve growth parameters and plant health of landscaping plants under extreme temperatures, influenced by global climate changes. Cocoplum (Chrysobalanus icaco), cabbage palm (Sabal palmetto), satinleaf (Chrysophyllum oliviforme), and wild coffee (Psychotria nervosa) plants received an initial slow-release fertilizer of 15 g/pot with an 8N-3P-9K composition. Silicon was applied as a 1% silicic acid solution, with concentrations ranging from 0 g/pot to 6 g/pot of 7.5 L. Evaluations were carried out every 30 days, continuing until 180 days after the treatment was completed. Phenotypic traits, including leaf count and plant height, were assessed alongside measurements from handheld optical non-destructive sensors. these measurements included the normalized difference vegetation index (NDVI), SPAD-502, and atLEAF chlorophyll meters. Application of 4 g/pot and 6 g/pot of silicon significantly improved NDVI values (0.78). Conversely, cocoplum plants exhibited greater plant height (79.6) at 0 g/pot silicon compared to other treatments. In wild coffee samplings, the control group showed the highest plant height and SPAD readings (93.49) compared to other treatments. Interestingly, the control treatment also demonstrated a superior atLEAF value as compared to other treatments, while the tallest samplings were observed with 6 g/pot of silicon (62.82) in cabbage palm plants. the findings indicate that silicon application positively influenced plant growth, particularly evident in cabbage palms. However, cocoplum and wild coffee exhibited a negative correlation between plant height and silicon concentrations.

关键词： Silicon Application Chlorophyll Content Cocoplum Cabbage Palm Satinleaf Wild Coffee

Near resonance vibration isolation on a levered-dual response(LEDAR)Coulomb-damped system by differential preloads/offsets in linear springs

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Applied Mathematics and Mechanics(English Edition) 2024年第6期45卷 1033-1050页

作者： t.I.tOLUWALOJU C.K.tHEIN D.HALIM Department of Mechanical Materials and Manufacturing EngineeringUniversity of Nottingham Ningbo ChinaNingbo 315100Zhejiang ProvinceChina Nottingham Ningbo China Beacons of Excellence Research and Innovation Institute University of Nottingham Ningbo ChinaNingbo 315048Zhejiang ProvinceChina

the levered-dual response(LEDAR)Coulomb-damped system attains near resonant vibration isolation by differential preloads/offsets in linear *** takes the advantages of both the preloads/offsets in linear springs and the guiderail friction for realizing different levels of vibration *** isolation capacities are investigated on the strategies with both the horizontal and vertical guiderails,with the horizontal rail only,and without *** compressive preloads generally result in the consumption of most of the initial excitation energy so as to overcome the potential *** isolation onsets at the frequency ratio of 1∓0.095 on the left-hand side(LHS)and the right-hand side(RHS)of the lever are relative to the load plate *** observed near resonant isolation thus makes the LEDAR system a candidate for the isolation of the mechanical systems about resonance while opening a path for simultaneous harvesterisolation functions and passive functions at extreme frequencies.

关键词： lever ratio Coulomb damping preload tension/compression isolation band/depth offset potential

Development of endemicity and conservation importance indices for tropical forests and the floral diversity assessment of *** in Benguet,Philippines

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Journal of Mountain Science 2024年第3期21卷 786-804页

作者： Johndale Rein t.BULLONG Jim P.SILVERIO Joanna I.ALAFAG Maricel A.GURON Jones t.NAPALDEt Department of Environmental Science Benguet State UniversityLa Trinidad 2601Philippines Department of Biology Benguet State UniversityLa Trinidad 2601Philippines

the scientific community faces the challenge of measuring progress toward biodiversity targets and indices have been traditionally ***,recent inventories in secondary tropical mountain forests using traditional biodiversity indices have yielded results that are indistinct with primary *** shows the need to develop complementary indices that goes beyond species count but integrates the distribution and conservation status of the *** study developed endemicity and conservation importance index for tropical forest that incorporated the distribution and conservation status of the *** indices were applied to ***,a remnant primary mossy forest in Buguias,Benguet,Philippines,that resulted to endemicity index of 81.07 and conservation importance index of *** these with secondary forest sites with comparable Shannon-Wiener,Simpson,Evenness and Margalef’s indices,our endemicity and conservation indices clearly differentiates primary forest(our study site)with higher values from secondary forests with much lower ***,we are proposing these indices for a direct but scientifically-informed identification of specific sites for conservation and protection in tropical ***,our study documented a total of 168 vascular plant species(79 endemic and 12 locally threatened species)in *** are of tropical elements for both generic and species levels with some temperate elements that could be attributed to the site's high elevation and semi-temperate *** are important baseline information for conservation plans and monitoring of tropical mossy forests.

关键词： Endemicity index Conservation importance index Cordillera Central Range Floristic element Jaccard Index of Similarity

Grazing Pressure and Plant Functional types in Puna Highlands,Northwestern Argentina

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Phyton-International Journal of Experimental Botany 2024年第5期93卷 1067-1080页

作者： Quiroga Mendiola Mariana tálamo Andrés IPAF NOA—INtA(National Institute for Agricultural technology) Posta de HornillosJujuy4622Argentina Facultad de Ciencias Naturales Universidad Nacional de SaltaSalta4400Argentina Instituto de Bio y Geociencias del NOA(IBIGEO) UNSa-CONICET.Laboratorio de Ecología Aplicada a la Conservación(LEAC)Facultad de Ciencias NaturalesUniversidad Nacional de SaltaSalta4400Argentina Maestría en Gestión Ambiental Escuela de NegociosUniversidad Católica de Salta(UCASAL)Salta4400Argentina

the Puna grasslands support grazing systems that produce meat and wool in multi-species herds,especially from llama(Lama glama)and ***,it is yet unknown whether grazing pressure can modify grassland structure and Plant Functional types diversity and cover in Puna *** analyzed the relationship between grazing pressure and Plant Functional types by comparing transects located near stockyards(high grazing pressure)and far from them(low pressure)and by evaluating the relationship between the Plant Functional types cover to a Grazing Pressure Index(GPI).this index incorporates the heterogeneity of traditional pastoral *** two ecological sites(Ciénego and tolar),we sampled paired transects(near-far).Plots near and far from corrals were similar in all the variables measured except for plots in tolar,which tend to have higher total cover,possibly due to fecal fertilization near ***,we recorded an increase in total cover and grass cover at higher GPI in Ciénego,while in tolar we found lower values of total cover and herbaceous dicotyledonous cover at intermediate intensities of *** only negative relationship found was the cover of clonal and non-clonal shrubs,possibly explained by the greater use of these shrubs as firewood near *** summary,our study does not show important changes in Plant Functional types as a function of grazing pressure in the studied grasslands probably because grazing pressure is diluted or diminished when livestock rotates in different areas and grazing durations ***,the long grazing history with which the Puna has evolved could also contribute to the co-structuration between native vegetation and livestock farming.

关键词： Natural grasslands Puna herbivory ecological perturbation

A Deep Dive into the trajectory and transformation of Fintech in Colombia through the Case of PtM Colombia-A Secondary Publication

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Proceedings of Business and Economic Studies 2024年第2期7卷 234-244页

作者： Yanni Gabriel GuacanemeÁlvarez Catalina Medina Ardila Nadeska Gallardo Licháa Otilia Miladys gil Hoyos University Corporation of Sabaneta(Unisabaneta) SabanetaColombia Remington University Corporation MedellínColombia

this research focuses on analyzing and understanding the evolution and impact of fintech companies in Colombia,using PtM Colombia as a case study,a company that has undergone a significant transformation from its beginnings as a provider of physical recharges to its current *** a comprehensive platform for digital financial *** current research uses a qualitative descriptive approach and emphasizes understanding the perceptions and experiences in the field of Fintech in Colombia,particularly in the case of PtM *** study revealed that adaptability and customer orientation have been fundamental in the evolution of PtM,allowing the company to expand its range of services by actively listening to the needs of its users and adjusting its strategies *** addition,an accelerated and diversified growth of Fintech will be observed in Colombia,particularly in sectors such as credit and payments,driven by a constantly advancing technological environment and a regulatory framework that,although it presents challenges,also offers opportunities for financial *** growth has impacted the traditional banking sector,which,instead of being replaced by Fintech,is finding new forms of collaboration and coexistence that benefit both parties and,above all,the end *** conclusion,the study highlights how Fintech in Colombia,represented by cases such as PtM,is redefining the financial landscape through the adoption of advanced technologies,collaboration with traditional banking,and strong customer orientation.

关键词： Financial technology Financial inclusion Fintech ecosystem Financial transformation

Energy exchange between charged relativistic fluids in f(t) gravity

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Communications in theoretical Physics 2024年第10期76卷 108-120页

作者： Z Yousaf U A Khokhar Nasser Bin turki t Suzuki Department of Mathematics University of the Punjab Quaid-i-Azam Campus Department of Mathematics College of Science King Saud University Department of Regional Management Faculty of Management Fukushima College

this study focuses on the effects of a polytropic fluid on a charged gravitational source within f(t) gravity, where t is the torsion scalar. We investigate how the electromagnetic field affects the flow of energy in spherically symmetric and static celestial objects that contain relativistic fluids. By using the gravitational decoupling technique, we analyze the effects of polytropic fluid on the dynamics of the gravitational source, accompanied by the matching of the interior geometry with an exterior at the hypersurface Σ. Finally, with the help of the tolman ⅡV solution, we observe the conduct of energy conditions with the existence of charge using f(t)field equations and got the intended outcomes.

关键词： anisotropy complexity energy exchange hydrodynamics self-gravitating systems

Interindividual Age-Independent Differences in Human CX43 Impact Ventricular Arrhythmic Risk

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Research 2024年第3期6卷 417-432页

作者： Laura García-Mendívil María Pérez-Zabalza Antoni Oliver-Gelabert JoséMaría Vallejo-gil Javier Fañanás-Mastral Manuel Vázquez-Sancho Javier AndréBellido-Morales Alexánder Sebastián Vaca-Núñez Carlos Ballester-Cuenca Emiliano Diez Laura Ordovás Esther Pueyo Biomedical Signal Interpretation and Computational Simulation group(BSICoS) Aragón Institute of Engineering ResearchUniversity of ZaragozaZaragoza 50018Spain BSICoS Instituto de Investigación Sanitaria Aragón(IISA)Zaragoza 50018Spain Centro Universitario de la Defensa(CUD) Zaragoza 50090Spain. Department of Cardiovascular Surgery University Hospital Miguel ServetZaragoza 50009Spain. Institute of Experimental Medicine and Biology of Cuyo(IMBECU) CONICETMendoza 5500Argentina. Fundación Agencia Aragonesa para la Investigación y el Desarrollo(ARAID) Zaragoza 50018Spain. Biomedical Research Networking Center in Bioengineering Biomaterials and Nanomedicine(CIBER-BBN)Zaragoza 50018Spain.

Connexin 43 (CX43) is one of the major components of gap junctions, the structures responsible for the intercellular communication and transmission of the electrical impulse in the left ventricle. there is limited information on the histological changes of CX43 with age and their effect on electrophysiology, especially in humans. Here, we analyzed left ventricular biopsies from living donors starting at midlife to characterize age-related CX43 remodeling. We assessed its quantity, degree of lateralization, and spatial heterogeneity together with fibrotic deposition. We observed no significant age-related remodeling of CX43. Only spatial heterogeneity increased slightly with age, and this increase was better explained by biological age than by chronological age. Importantly, we found that CX43 features varied considerably among individuals in our population with no relevant relationship to age or fibrosis content, in contrast to animal species. We used our experimental results to feed computational models of human ventricular electrophysiology and to assess the effects of interindividual differences in specific features of CX43 and fibrosis on conduction velocity, action potential duration, and arrhythmogenicity. We found that larger amounts of fibrosis were associated with the highest arrhythmic risk, with this risk being increased when fibrosis deposition was combined with a reduction in CX43 amount and/or with an increase in CX43 spatial heterogeneity. these mechanisms underlying high arrhythmic risk in some individuals were not associated with age in our study population. In conclusion, our data rule out CX43 remodeling as an age-related arrhythmic substrate in the population beyond midlife, but highlight its potential as a proarrhythmic factor at the individual level, especially when combined with increased fibrosis.

关键词： CX43 rhythm Independent