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holographic dark energy in non-conserved gravity theory

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Communications in Theoretical Physics 2024年第4期76卷 126-133页

作者： h r Fazlollahi Institute of gravitation and Cosmology Peoples Friendship University of Russia(RUDN University)6 Miklukho-Maklaya StMoscow117198Russia

recently, reconsidering the rastall idea T_(μ;νν)^(v)=α_(,μ) through relativistic thermodynamics gives a new form for the scalar field α which led us to construct modern modified theory of gravity debugged ‘non-conserved gravity theory’ Fazlollahi 2023 Euro. Phys. J. C 83 923. This theory unlike other modified theories of gravity cannot directly explain the current acceleration expansion in the absence of the cosmological constant and or existence of other forms of dark energy. hence, in this study we have reinvestigated holographic dark energy Ρ_(X)~h^(2) in the non-conserved theory of gravity. In this context, the density and pressure of dark energy depend on the non-conserved term and density of the dust matter field. As shown, due to non-conservation effects on large-scale structures, unlike the original holographic model, our model onsets an acceleration epoch for the current Universe satisfies observations. Moreover, the interaction and viscous scenarios are studied for this model.

关键词： non-conserved gravity covariant form of thermodynamics holographic dark energy

Control system design for a pressure-tube-type supercritical water-cooled nuclear reactor via a higher order sliding mode method

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Nuclear Science and Techniques 2024年第1期35卷 145-154页

作者： M.hajipour g.r.Ansarifar Department of Nuclear Engineering Faculty of PhysicsUniversity of IsfahanIsfahan 81746-73441Iran

Nuclear power plants exhibit non-linear and time-variable dynamics.Therefore,designing a control system that sets the reactor power and forces it to follow the desired load is complicated.A supercritical water reactor(SCWr)is a fourth-generation conceptual reactor.In an SCWr,the non-linear dynamics of the reactor require a controller capable of control-ling the nonlinearities.In this study,a pressure-tube-type SCWr was controlled during reactor power maneuvering with a higher order sliding mode,and the reactor outgoing steam temperature and pressure were controlled simultaneously.In an SCWr,the temperature,pressure,and power must be maintained at a setpoint(desired value)during power maneuvering.reactor point kinetics equations with three groups of delayed neutrons were used in the simulation.higher-order and classic sliding mode controllers were separately manufactured to control the plant and were compared with the PI controllers speci-fied in previous studies.The controlled parameters were reactor power,steam temperature,and pressure.Notably,for these parameters,the PI controller had certain instabilities in the presence of disturbances.The classic sliding mode controller had a higher accuracy and stability;however its main drawback was the chattering phenomenon.hOSMC was highly accurate and stable and had a small computational cost.In reality,it followed the desired values without oscillations and chattering.

关键词： Supercritical water nuclear reactor higher order sliding mode controller Steam temperature Steam pressure Point kinetics model

Flexible neural probes:a review of the current advantages,drawbacks,and future demands

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2024年第2期25卷 153-167页

作者： Sara PIMENTA Joao r.FrEITAS Joséh.COrrEIA CMEMS-UMinho University of MinhoGuimarães4800-058Portugal LABBELS-Associate Laboratory Braga/GuimarãesPortugal

Brain diseases affect millions of people and have a huge social and economic impact.The use of neural probes for studies in animals has been the main approach to increasing knowledge about neural network functioning.Ultimately,neuroscientists are trying to develop new and more effective therapeutic approaches to treating neurological disorders.The implementation of neural probes with multifunctionalities(electrical,optical,and fluidic interactions)has been increasing in the last few years,leading to the creation of devices with high temporal and spatial resolution.Increasing the applicability of,and elements integrated into,neural probes has also led to the necessity to create flexible interfaces,reducing neural tissue damage during probe implantation and increasing the quality of neural acquisition data.In this paper,we review the fabrication,characterization,and validation of several types of flexible neural probes,exploring the main advantages and drawbacks of these devices.Finally,future developments and applications are covered.Overall,this review aims to present the currently available flexible devices and future appropriate avenues for development as possible guidance for future engineered devices.

关键词： Brain knowledge Flexible interface Multifunctional probe

Proton-neutron symplectic model description of ^(106)Cd

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Chinese Physics C 2024年第3期48卷 169-179页

作者： h.g.ganev Joint Institute for Nuclear research DubnaRussia Institute of Mechanics Bulgarian Academy of SciencesSofiaBulgaria

In this study,a microscopic shell-model description of the low-lying collective states in the weakly deformed nucleus ^(106)Cd within the recently proposed microscopic version of the Bohr-Mottelson model is provided.A good description of the excitation energies of the lowest ground,γ,andβquasibands is obtained without the adjustable kinetic energy term.Furthermore,γdegrees of freedom are shown to play a crucial role in the description of spectroscopy of this nucleus.A modified SU(3)SU(3)preserving high-order interaction is used to produce aγ-unstable type of odd-even staggering,observed experimentally between the states of the quasi-γband.The current approach enables the characterization of observed intraband and interband quadrupole collectivity.The findings of this study propose an alternative interpretation of the fundamental question regarding the nature of low-energy vibrations,as well as the emergence of deformation and collectivity in weakly deformed atomic nuclei.

关键词： shell-model version of the Bohr-Mottelson model proton-neutron symplectic model Sp(12,r)dynamical algebra quadrupole dynamics

Multi-objective method of selecting performance-based local climatic zones using binomial logistic regression in warm and humid climate

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Frontiers of Architectural research 2024年第1期13卷 184-200页

作者： g.r.Madhavan Dorairaj Kannamma Department of Architecture National Institute of TechnologyTiruchirappalliTamil Nadu 620015India

Urban agglomeration is a serious concern due to its high energy usage and impact on the local climate.Developing countries strive to determine the development path to optimize energy usage.The present study aims to examine the local climatic zones(LCZs)performance in warm and humid climate through a multi-objective approach for the residential sector.The performance is assessed by evaluating the urban microclimate and cooling load consumption for both summer and winter months using binomial logistic regression.The study concludes that LCZ 2_(3)(compact mid-rise with open low-rise)and LCZ 6_(B)(open low-rise with scattered trees)perform better for 80%and 50%of total hours in warm and humid climate.It also proves the presence of significant performance differences between mid-rise and low-rise zones.The intra-zonal differences between the climatic variables are higher than the inter-zonal differences due to the impact of land surface temperature(LST).The high aspect ratio and low sky view factor of LCZ 2_(3) help the residents in that morphology in enhancing better thermal comfort and reducing cooling load consumption.The present study contributes to building regulation policymakers by providing information on the suitable morphology for warm and humid climate.

关键词： LCZ Outdoor thermal comfort Cooling load LST and urban morphology indicators

A novel diurnal and seasonal variation analysis of BTEX in Bengaluru urban area

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research in Cold and Arid regions 2024年第1期16卷 14-19页

作者： h.N.Sowmya M.Dinamani g.P.Shivashankara h.K.ramaraju B.S.Surendra Vijaya V.Shanbhag r.Prajwal Department of Civil Engineering Dayananda Sagar College of EngineeringBangalore 560078India Department of Chemistry Dayananda Sagar College of EngineeringBangalore 560078India Department of Physics GFGCVijayanagarBengaluru 560040India

In the urban atmosphere of Bengaluru, various volatile organic compounds(VOCs), particularly Benzene,Toluene, Ethylbenzene, and Xylene(BTEX), have shown an increasing trend in concentration. The present research was conducted during summer and monsoon seasons, focusing on Kadubeesanahalli, a high-traffic area within the Bengaluru Metropolitan City. hourly sample data was collected using a BTEX analyzer(Model gC955-600) and subsequently transformed into daily, monthly, and seasonal values. The study revealed distinct patterns in benzene concentrations. Benzene levels were lowest during the early morning hours, specifically from 1:00 a.***.to 7:00 a.m.. Concentrations then increased from 7:00 a.m. to 9:00 a.m. and again from 4:00 p.m. to 11:00 p.m.,corresponding to the morning and evening peak traffic hours. however, between 10:00 a.m. and 4:00 p.m., the concentration decreased due to reduced traffic levels. These diurnal variations in benzene concentration are influenced by meteorological parameters. Comparing the two seasons, higher concentrations of Benzene, EthylBenzene, and MP-xylene were observed during the summer season. This increase is attributed to the elevated temperatures during summer, which promote the vaporization of BTEX compounds. Conversely, lower BTEX concentrations were recorded during the monsoon season due to the wet deposition process. The observed positive correlation(r > 0.5) among BTEX parameters strongly suggests a common source, most likely originating from vehicular emissions.

关键词： BTEX Summer variation Meteorological parameters Correlation

hydrodynamic function and spring constant calibration of FluidFM micropipette cantilevers

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Microsystems & Nanoengineering 2024年第1期10卷 277-286页

作者： Attila Bonyár Ágoston g.Nagy hans gunstheimer gotthold Fläschner robert horvath Department of Electronics Technology Faculty of Electrical Engineering and InformaticsBudapest University of Technology and EconomicsBudapestHungary Nanobiosensorics Laboratory Institute of Technical Physics and Materials ScienceCentre for Energy ResearchHUN-RENBudapestHungary Nanosurf Ag Gräubernstrasse 12CH-4410 LiestalSwitzerland

Fluidic force microscopy(FluidFM)fuses the force sensitivity of atomic force microscopy with the manipulation capabilities of microfluidics by using microfabricated cantilevers with embedded fluidic channels.This innovation initiated new research and development directions in biology,biophysics,and material science.To acquire reliable and reproducible data,the calibration of the force sensor is crucial.Importantly,the hollow FluidFM cantilevers contain a row of parallel pillars inside a rectangular beam.The precise spring constant calibration of the internally structured cantilever is far from trivial,and existing methods generally assume simplifications that are not applicable to these special types of cantilevers.In addition,the Sader method,which is currently implemented by the FluidFM community,relies on the precise measurement of the quality factor,which renders the calibration of the spring constant sensitive to noise.In this study,the hydrodynamic function of these special types of hollow cantilevers was experimentally determined with different instruments.Based on the hydrodynamic function,a novel spring constant calibration method was adapted,which relied only on the two resonance frequencies of the cantilever,measured in air and in a liquid.Based on these results,our proposed method can be successfully used for the reliable,noise-free calibration of hollow FluidFM cantilevers.

关键词： spring cantilever function

Structural changes in the obese brain

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Neural regeneration research 2024年第12期19卷 2561-2562页

作者： Anna r.r.Da Conceicao Marcelo N.N.Vieira Fernanda g.De Felice D’Or Institute for research and Education Rio de JaneiroBrazil Institute of Medical Biochemistry Leopoldo De Meis Federal University of Rio de JaneiroRio de JaneiroBrazil Centre for Neuroscience Studies Department of Biomedical and Molecular Sciences&Department of PsychiatryQueen’s UniversityKingstonONCanada

Obesity represents a major global health concern,with widespread growing prevalence and severe consequences for the quality of life and life expectancy of affected individuals and for the economic burden of healthcare systems(Prospective Studies Collaboration,2009).Obesity is a well-established risk factor for a variety of conditions including metabolic,vascula r,and heart diseases,and seve ral types of cancer(Prospective Studies Collaboration,2009).

关键词： diseases consequences prevalence

Nonlinear corrections for the nuclear gluon distribution in eA processes

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Chinese Physics C 2024年第3期48卷 52-64页

作者： g.r.Boroun B.rezaei F.Abdi Department of Physics Razi UniversityKermanshah 67149Iran.

An analytical study with respect to the nonlinear corrections for the nuclear gluon distribution function in the next-to-leading order approximation at small x is presented.We consider the nonlinear corrections to the nuclear gluon distribution functions at low values of x and Q^(2) using the parametrization F_(2)(x,Q^(2))and the nuclear modification factors obtained from the Khanpour-Soleymaninia-Atashbar-Spiesberger-guzey model.The CT18 gluon distribution is used for the baseline proton gluon density at Q^(2)_(0)=1.69geV2.We discuss the behavior of the gluon densities in the next-to-leading order and the next-to-next-to-leading order approximations at the initial scale Q^(2)_(0),as well as the modifications due to the nonlinear corrections.We find that the QCD nonlinear corrections are more significant for the next-to-leading order accuracy than the next-to-next-to-leading order for light and heavy nuclei.The results of the nonlinear gLr-MQ evolution equation are similar to those obtained with the rausch-guzey-Klasen gluon upward and downward evolutions within the uncertainties.The magnitude of the gluon distribution with the nonlinear corrections increases with a decrease in x and an increase in atomic number A.

关键词： gluon distribution nonlinear corrections light and heavy nuclei low x physics