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Integralinput-to-statestability ystemswithsmalldelays Integral input-to-state stability of systems with small delays

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Control Theory and Technology 2024年第3期22卷 455-467页

作者： r.H.Harsha Nawarathna Yuandan Lin Yuan Wang Department of Mathematical Sciences Florida Atlantic UniversityBoca RatonFL 33431USA

We consider how small delays affect the integral-input-to-state stability(iss)property for a *** result is similar to the input-to-state stability(Iss)result obtained in[1]:the iss property will be preserved in a practical and semi-global manner if the delay interval is small ***,since the iss quantifies the robust stability in terms of a generalized Li norm of the inputs instead of a generalized Loo norm of the inputs for the Iss case,the techniques and proofs for the Iss case do not apply to the iss case *** the proofs in[1]are based on the Lyapunov-razumikhin approach,our proofs are based on the iss-Lyapunov functions for the zero-delay *** addition to the interest by its own in showing how the iss property is affected by small delays,the result also serves to the study of the iss property for singularly perturbed systems.

关键词： Integral-input-to-state stability Nonlinear systems Small delays Lyapunov method

Probing the Bardeen-Kiselev black hole with the cosmological constant caused by Einstein equations coupled with nonlinear electrodynamics using quasinormal modes and greybody bounds

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Communications in Theoretical Physics 2024年第6期76卷 102-119页

作者： S r Wu B Q Wang Z W Long College of Physics Guizhou UniversityGuiyang 550025China College Pharmacy Guizhou University of Traditional Chinese MedicineGuiyang 550025China

In this work,we investigate a static and spherically symmetric Bardeen-Kiselev black hole(BH)with the cosmological constant,which is a solution of the Einstein-non-linear Maxwell field *** compute the quasinormal frequencies for the Bardeen-Kiselev BH with the cosmological constant due to electromagnetic and gravitational *** varying the BH parameters,we discuss the behavior of both real and imaginary parts of the BH quasinormal frequencies and compare these frequencies with the reissner-Nordström-de Sitter BH surrounded by quintessence(rN-dSQ).Interestingly,it is shown that the responses of the Bardeen-Kiselev BH with the cosmological constant and the rN-dSQ under electromagnetic perturbations are different when the charge parameter q,the state parameter w and the normalization factor c are varied;however,for the gravitational perturbations,the responses of the Bardeen-Kiselev BH with the cosmological constant and the rN-dSQ are different only when the charge parameter q is ***,compared with the gravitational perturbations,the electromagnetic perturbations can be used to understand nonlinear and linear electromagnetic fields in curved spacetime *** interesting observation is that,due to the presence of Kiselev quintessence,the electromagnetic perturbations around the Bardeen-Kiselev BH with the cosmological constant damps faster and oscillates slowly;for the gravitational perturbations,the quasinormal mode decays slowly and oscillates *** also study the reflection and transmission coefficients along with the absorption cross section in the Bardeen-Kiselev BH with the cosmological constant;it is shown that the transmission coefficients will increase due to the presence of Kiselev quintessence.

关键词： quasinormal modes greybody factors Bardeen-Kiselev black hole with cosmological constant

Insights on the Emerging Therapeutic Potential of Terpenoids as Anti-inflammatory Agents:A Scoping review

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Journal of Bio-X research 2024年第1期7卷 20-35页

作者： Mohini devi Prabhjeet Kaur Bamrah rajat Goyal Manjusha Choudhary Hitesh Chopra Institute of Pharmaceutical Sciences Kurukshetra UniversityKurukshetra 136119HaryanaIndia MM College of Pharmacy Maharishi Markandeshwar(Deemed to be University)Mullana-Ambala 133207HaryanaIndia Department of Biosciences Saveetha School of EngineeringSaveetha Institute of Medical and Technical SciencesChennai 602105Tamil NaduIndia

Background:Inflammatory diseases are among the leading causes of health issues that considerably influence health care *** the notable advancements in medical treatment that have been made in recent years,natural products with biological activity still play essential roles in a variety of anti-inflammatory *** study and identification of novel treatments for the adverse effects of available synthetic anti-inflammatory agents warrant further ***:This study focused on the emerging therapeutic potential of terpenoid products as anti-inflammatory ***:The literature reveals that secondary metabolites obtained from medicinal plants,*** and terpenoids and their nanoformulations,are effective for the treatment of inflammation in *** terpenes are a broad class of secondary metabolites that are rich in monoterpenes,diterpenes,triterpenes,tetraterpenes,ceramides,and sesquiterpenes and have various therapeutic applications,such as antitumor,antibacterial,antimicrobial,analgesic and anti-inflammatory *** studies have shown that terpenes can decrease inflammation-associated symptoms by reducing the release of proinflammatory cytokines,including nuclear transcription factor-kappa B,interleukins,tumor necrosis factor-alpha,and other inflammatory ***:This review describes the latest knowledge of the different terpenoid-derived natural and synthetic compounds that have been isolated from plant sources in recent years and their anti-inflammatory potential and therapeutic mechanism of ***,this study focused on terpenoid-based nanoformulations with enhanced bioavailability and improved therapeutic efficacy as anti-inflammatory agents.

关键词： conditions. formulation considerably

Design of a large-scale model for wind tunnel test of a multiadaptive flap concept

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Chinese Journal of Aeronautics 2024年第2期37卷 58-80页

作者： Mürüvvet Sinem SICIM DEMIrCI rosario PECOrA Metin Orhan KAYA Aeronautical Engineering Department Istanbul Technical UniversityIstanbulTurkey Industrial Engineering Department University of Naples Federico IINapoliItaly

The design and application of morphing systems are ongoing issues compelling the aviation *** Clean Sky-program represents the most significant aeronautical research ever launched in Europe on advanced technologies for greening next-generation *** primary purpose of the program is to develop new concepts aimed at decreasing the effects of aviation on the environment,increasing reliability,and promoting eco-friendly *** ambitions are pursued through research on enabling technologies fostering noise and gas emissions reduction,mainly by improving aircraft aerodynamic *** the Clean Sky framework,a multimodal morphing flap device was designed based on tight industrial requirements and tailored for large civil aircraft *** flap is deployed in one unique setting,and its cross section is morphed differently in take-off and landing to get the necessary extra lift for the specific flight ***,during the cruise,the tip of the flap is deflected for load control and induced drag *** manufacturing the first flap prototype,a high-speed(Ma=0.3),large-scale test campaign(geometric scale factor 1:3)was deemed necessary to validate the performance improvements brought by this novel system at the aircraft *** the other hand,the geometrical scaling of the flap prototype was considered impracticable due to the unscalability of the embedded mechanisms and actuators for shape ***,a new architecture was conceived for the flap model to comply with the scaled dimensions requirements,withstand the relevant loads expected during the wind tunnel tests and emulate the shape transition capabilities of the true-scale *** strategies were developed to effectively morph the model during wind tunnel tests while ensuring the robustness of each morphed configuration and maintaining adequate stiffness levels to prevent undesirable deviations from the intended aerodynamic ***,

关键词： Morphing structures Smart aircraft Morphing flap Adaptive systems Finger-like ribs Wind tunnel tests Large-scale morphing archi-tectures Variable camber airfoil

Deep bed filtration model for cake filtration and erosion

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Applied Mathematics and Mechanics(English Edition) 2024年第2期45卷 355-372页

作者： L.I.KUZMINA Y.V.OSIPOV A.r.PESTErEV Department of Applied Mathematics HSE UniversityMoscow 101000Russia Department of Computer Science and Applied Mathematics Moscow State University of Civil EngineeringMoscow 129337Russia

Many phenomena in nature and technology are associated with the filtration of suspensions and colloids in porous media. Two main types of particle deposition,namely, cake filtration at the inlet and deep bed filtration throughout the entire porous medium, are studied by different models. A unified approach for the transport and deposition of particles based on the deep bed filtration model is proposed. A variable suspension flow rate, proportional to the number of free pores at the inlet of the porous medium, is considered. To model cake filtration, this flow rate is introduced into the mass balance equation of deep bed filtration. For the cake filtration without deposit erosion,the suspension flow rate decreases to zero, and the suspension does not penetrate deep into the porous medium. In the case of the cake filtration with erosion, the suspension flow rate is nonzero, and the deposit is distributed throughout the entire porous medium. An exact solution is obtained for a constant filtration function. The method of characteristics is used to construct the asymptotics of the concentration front of suspended and retained particles for a filtration function in a general form. Explicit formulae are obtained for a linear filtration function. The properties of these solutions are studied in detail.

关键词： deep bed filtration cake filtration porous medium particle deposition and erosion analytical solution concentration front

Hybrid LES/rANS Simulations of Compressible Flow in a Linear Cascade of Flat Blade Profiles

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Journal of Thermal Science 2024年第5期33卷 1839-1850页

作者： Jaromír PrIHODA Petr STrAKA David SIMUrDA Petr SIDLOF Jan LEPICOVSKY Institute of Thermomechanics of the Czech Academy of Sciences Dolejskova 1402/518200 Prague 5Czech Republic Aerospace research and Test Centre Beranovych 13019905 PragueCzech Republic Technical University of Liberec Faculty of MechatronicsStudentska 246117 Liberec 1Czech Republic

The paper reports on 3D numerical simulations of unsteady compressible airflow in a blade cascade consisting of flat profiles using a hybrid LES/rANS approach including a transition *** a first step towards simulation of blade flutter in turbomachinery,various incidence angle offsets of the middle blade were *** simulations were run for the flow regime characterized by outlet isentropic Mach number M_(is)=0.5and zero *** results of the LES/rANS simulations(pressure and Mach number distributions)were compared to a baseline rANS model,and to experimental data measured in a high-speed wind *** numerical results show that both methods overpredict flow separation taking place at the leading *** this regard,the hybrid LES/rANS method does not provide superior results compared to the traditional rANS ***,the LES/rANS results also capture vortex shedding from the blunt trailing *** frequency of the trailing edge vortex shedding in CFD simulations matches perfectly the spectral peak recorded during wind tunnel measurements.

关键词： numerical simulation blade cascade hybrid LES/rANS

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 *** countries strive to determine the development path to optimize energy *** present study aims to examine the local climatic zones(LCZs)performance in warm and humid climate through a multi-objective approach for the residential *** performance is assessed by evaluating the urban microclimate and cooling load consumption for both summer and winter months using binomial logistic *** 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 *** also proves the presence of significant performance differences between mid-rise and low-rise *** 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 *** 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

The future is frozen:cryogenic CMOS for high-performance computing

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Chip 2024年第1期3卷 43-54页

作者： r.Saligram A.raychowdhury Suman Datta School of Electrical and Computer Engineering Georgia Institute of TechnologyAtlantaUSA

Low temperature complementary metal oxide semiconductor(CMOS)or cryogenic CMOS is a promising avenue for the continuation of Moore’s law while serving the needs of high performance *** temperature as a control“knob”to steepen the subthreshold slope behavior of CMOS devices,the supply voltage of operation can be reduced with no impact on operating *** the optimal threshold voltage engineering,the device ON current can be further enhanced,translating to higher *** this article,the experimentally calibrated data was adopted to tune the threshold voltage and investigated the power performance area of cryogenic CMOS at device,circuit and system *** also presented results from measurement and analysis of functional memory chips fabricated in 28 nm bulk CMOS and 22 nm fully depleted silicon on insulator(FDSOI)operating at cryogenic ***,the challenges and opportunities in the further development and deployment of such systems were discussed.

关键词： Cryogenic CMOS Design technology co-optimization High performance computing Parameter variation Threshold voltage engineering Cryogenic Memories Interconnects

Visual Enhancement of Underwater Images Using Transmission Estimation and Multi-Scale Fusion

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Computer Systems Science & Engineering 2023年第3期44卷 1897-1910页

作者： r.Vijay Anandh S.rukmani devi Department of Electronics and Communication Engineering RMK College of Engineering and TechnologyTiruvallurTamilnadu601206India Department of Electronics and Communication Engineering RMD Engineering CollegeGummidipundiTamilnadu601206India

The demand for the exploration of ocean resources is increasing *** image data plays a significant role in many research *** this,the visual quality of underwater images is degraded because of two main factors namely,backscattering and ***,visual enhancement has become an essential process to recover the required data from the *** algorithms had been proposed in a decade for improving the quality of *** paper aims to propose a single image enhancement technique without the use of any external *** that,the degraded images are subjected to two main processes namely,color correction and image ***,veiling light and transmission light is estimated tofind the color required for *** light refers to unwanted light,whereas transmission light refers to the required light for color *** estimated outputs are applied in the scene recovery *** image obtained from color correction is subjected to a fusion process where the image is categorized into two versions and applied to white balance and contrast enhancement *** resultants are divided into three weight maps namely,luminance,saliency,chromaticity and fused using the Laplacian *** results obtained are graphically compared with their input data using rGB Histogram ***,image quality is measured and tabulated using underwater image quality measures.

关键词： Underwater image backscattering attenuation image fusion veiling light white balance laplacian pyramid