关键词:
3D Navier-Stokes-Voigt equations;admissible trajectories set;admissible control set;feedback control;time optimal control
摘要:
Abstract: In this article, we discuss a time optimal feedback control for asymmetrical 3D Navier–Stokes–Voigt equations. Firstly, we consider the existence of the admissible trajectories for the asymmetrical 3D Navier–Stokes–Voigt equations by using the well-known Cesari property and the Fillippove’s theorem. Secondly, we study the existence result of a time optimal control for the feedback control systems. Lastly, asymmetrical Clarke’s subdifferential inclusions and asymmetrical 3D Navier–Stokes–Voigt differential variational inequalities are given to explain our main results. Keywords: 3D Navier–Stokes–Voigt equations; admissible trajectories set; admissible control set; feedback control; time optimal control
作者机构:
[Yan, Rian] Hunan City Univ, Sch Math & Comp Sci, Yiyang 413000, Peoples R China.;[Zhao, Yige] Univ Jinan, Sch Math Sci, Jinan 250022, Peoples R China.
通讯机构:
[Zhao, YG ] U;[Yan, R ] H;Hunan City Univ, Sch Math & Comp Sci, Yiyang 413000, Peoples R China.;Univ Jinan, Sch Math Sci, Jinan 250022, Peoples R China.
摘要:
In this paper, a class of nonlinear fractional differential equations with periodic boundary condition is investigated. Although the nonlinearity of the equation and the Green's function are sign-changing, the results of the existence and nonexistence of positive solutions are obtained by using the Schaefer's fixed-point theorem. Finally, two examples are given to illustrate the main results.
摘要:
In the past ten years, networking experts have been more concerned about the rising energy consumption of communication networks. The software-defined networks approach is a way to make diverse and complicated network topologies simpler, more manageable, more adaptable, and more effective, including wireless body area networks. In order to streamline network administration, save operational costs, and promote innovation, software-defined networks are emerging as a new networking architecture that separates the data plane from the control plane. However, despite the importance of this issue, so far, no bibliometric study has been done on this issue. Hence, this study aims to use methods drawn from nature to optimize power usage in software-defined networks. Additionally, a thorough and original categorization of energy-efficient solutions has been offered. During the bibliographic review, the sections of interest of researchers and some bibliographic information in the form of statistical information are expressed. Therefore, searching and selecting relevant keywords are done using the VOSviewer tool. The data is extracted from valid databases. Guidelines for future research on software-defined networks are derived based on the existing research projects' findings and the gaps and constraints that have been found. The results showed that the algorithms inspired by nature were successful in striking a balance among resource usage, energy consumption, and network performance.
作者机构:
[Liu, Hean] Sehan Univ, Grad Sch, Dept Educ, Chungnam 58447, South Korea.;[Liu, Hean] Hunan City Univ, Coll Sci, Yiyang 413000, Peoples R China.;[Ko, Young Chun] Sehan Univ, Dept Teaching Profess, Chungnam 58447, South Korea.
通讯机构:
[Young Chun Ko] D;Department of Teaching Profession, Sehan University, Chonnam, South Korea
摘要:
Traffic congestion is easy to occur in multimedia networks, so fuzzy adaptive prediction of data transmission congestion is conducted to improve the stability of multimedia networks. A fuzzy adaptive prediction algorithm for data transmission congestion in multimedia networks is proposed. The data transmission structure model of multimedia networks is established, and the data transmission congestion status feature extraction and time series analysis are conducted. The self-coherent matched filter detection algorithm is adopted to analyze the congestion state of data transmission, and the high-order cumulant feature extraction and post-focus search are carried out on the output filtered data, and the accurate detection and extraction of abnormal features in traffic sequence is realized. It can be concluded that the fuzzy adaptive prediction of data transmission congestion in multimedia network is accurate and has strong resistance to interference. After 10 rounds of iteration, the detection probability always keeps at a high level and rises steadily, and the minimum detection probability is 78%, which ensures the stability and security of multimedia network.
摘要:
This analysis deals with the significances of bio-convection for the Carreau nanofluid flow over a stretched cylinder. The investigation is modified by suggesting the contribution of melting phenomenon and chemical reaction are also addressed. The thermal flow analysis is inspected in view of convective Marangoni boundary constraints. The thermal diffusivity parameter and Brownian motion are also considered. The useful parameters are followed for re-taking the dimensionless form of equations. The numerical scheme namely bv4c is implemented for computing the algorithmic simulations. The onset of all active involved quantities are investigated. The listed graphical outcomes yield that presence of melting parameter and Weissenberg number improves the nanofluid velocity while reverse trend for velocity profile is observed for curvature parameter. An increasing heat transfer pattern is executed for Biot number and curvature parameter. It is also interesting to observe that concentration profile reduces with Marangoni number and Marangoni ratio parameter.(c) 2022 International Association for Mathematics and Computers in Simulation (IMACS). Published by Elsevier B.V. All rights reserved.
通讯机构:
[Ayyaz Ahmad] D;Department of Mathematics, COMSATS University Islamabad, Attock Campus, Pakistan
关键词:
Fractional integral operator;Minkowski’s inequality;Mittag-Leffler function
摘要:
We present unified versions of Minkowski-type fractional integral inequalities with the help of fractional integral operator based on a unified Mittag-Leffler function. These inequalities provide new as well as already known fractional versions of Minkowski-type inequalities.
作者机构:
[Chu, Yu-Ming] Hunan City Univ, Coll Sci, Yiyang 413000, Hunan, Peoples R China.;[Chu, Yu-Ming] Huzhou Univ, Dept Math, Huzhou 313000, Zhejiang, Peoples R China.;[Chu, Yu-Ming] Hangzhou Normal Univ, Inst Adv Study Honoring Chen Jian Gong, Hangzhou 311121, Zhejiang, Peoples R China.;[Yassen, Mansour F.] Prince Sattam Bin Abdulaziz Univ, Dept Math, Coll Sci & Humanities Al Aflaj, Al Aflaj 11912, Saudi Arabia.;[Yassen, Mansour F.] Damietta Univ, Fac Sci, Dept Math, Dumyat 34517, Egypt.
通讯机构:
[PONGSAKORN SUNTHRAYUTH] D;Department of Mathematics and Computer Science, Faculty of Science and Technology, Rajamangala University of Technology Thanyaburi (RMUTT), Thanyaburi, Pathumthani 12110, Thailand
关键词:
Fourth Wave Cases;COVID-19 Fractional Model;Estimations of Parameters;Results and Discussions
期刊:
JOURNAL OF APPLIED ANALYSIS AND COMPUTATION,2022年12(4):1308-1327 ISSN:2156-907X
通讯作者:
Bin, M.
作者机构:
[Shi, Cuiyun] Guilin Univ Technol Nanning, Sch Basic Sci, Nanning 530001, Guangxi Provinc, Peoples R China.;[Li, Yunxiang; Bin, Maojun] Yulin Normal Univ, Guangxi Coll & Univ, Key Lab Complex Syst Optimizat & Big Data Proc, Yulin 537000, Guangxi Provinc, Peoples R China.;[Li, Yunxiang] Hunan City Univ, Coll Sci, Yiyang 413000, Hunan, Peoples R China.
通讯机构:
Guangxi Colleges and Universities Key Laboratory of Complex System Optimization and Big Data Processing, Yulin Normal University, Guangxi Province, Yulin, China
作者机构:
[Song, Ying-Qing] Hunan City Univ, Coll Sci, Yiyang 413000, Peoples R China.;[Animasaun, I. L.; Obideyi, B. D.] Fed Univ Technol Akure, Dept Math Sci, Fluid Dynam & Survey Res Grp, PMB 704, Akure, Nigeria.;[Shah, Nehad Ali; Chung, Jae Dong] Sejong Univ, Dept Mech Engn, Seoul 05006, South Korea.;[Mahrous, Y. M.] Univ Tabuk, Fac Community, Dept Studies & Basic Sci, POB 741, Tabuk 71491, Saudi Arabia.
通讯机构:
[Obideyi, B.D.; Animasaun, I.L.; Shah, N.A.; Chung, J.D.] D;Department of Mathematical Sciences, Nigeria;Department of Mechanical Engineering, South Korea
关键词:
Thermo-migration;Haphazard motion;Alumina and copper;Hybrid nanofluid;Water and ethylene glycol
摘要:
Sequel to all the published facts on the dynamics of water and ethylene glycol on a convectively heated surface conveying alumina and copper nanoparticles as applicable in engineering and industry, noting is known on the significance of haphazard motion and thermo-migration. For the case of Al2O3/Cu nanoparticles, the governing equations that model the transport phenomena along a vertical surface were non-dimensionalized. The obtained dimensionless equation (ODE BVP) was numerically solved in MATLAB using the text bvp4c in-built solver. The temperature distribution is minimal when convectively heating at the horizontal wall beneath the transport phenomenon is small in magnitude. When Biot number and thermo-migration are high, and the base fluid is less thick, there is minimal friction between the wall and the last layer of hybrid nanofluid due to increasing haphazard motion of alumina/copper nanoparticles (i.e., water). Heating of the base fluid is a factor for reducing friction as water is heated faster due to lower density than ethylene glycol.
摘要:
Nanofluids have exposed a significant promise in the thermal development of several industrial systems, and at the same time, the flow via needle has major applications in modern construction systems including microstructure electric gadgets and microscale cooling gadgets for thermal migration applications. According to these applications, the current investigation concentrates to deliberate on 2D steady, laminar and incompressible flow of magneto-Cross nanofluid towards the region of moving thin needle in the occurrence of Darcy–Forchheimer porous medium, Ohmic and viscous dissipation with chemical reaction and mixed convection. The new dimensionless similarity variables are introduced to convert the nonlinear expressions governing the flow and transfer of heat. The change in velocity, thermal and concentration profiles for various non-dimensional parameters is deliberated briefly and illustrated with the help of suitable plots. Further, analysis of skin friction and rate of heat transfer is done through graphs. The results obtained are validated by existing works and are found to have a good agreement. The result outcome reveals that advanced values of magnetic parameter and Weissenberg number slowdown the fluid velocity motion. Also, upshot in Brownian motion and thermophoresis parameters improves the thermal profile.
作者:
Zhang, Xiao-Hong;Saeed, Tareq;Algehyne, Ebrahem A.;El-Shorbagy, M. A.;El-Refaey, Adel M.;...
期刊:
Scientific Reports,2021年11(1) ISSN:2045-2322
通讯作者:
M. A. El-Shorbagy<&wdkj&>Muhammad Ibrahim
作者机构:
[Zhang, Xiao-Hong] Hunan City Univ, Coll Sci, Yiyang 413000, Peoples R China.;[Saeed, Tareq] King Abdulaziz Univ, Fac Sci, Dept Math, Nonlinear Anal & Appl Math NAAM Res Grp, POB 80203, Jeddah 21589, Saudi Arabia.;[Algehyne, Ebrahem A.] Univ Tabuk, Fac Sci, Dept Math, POB 741, Tabuk 71491, Saudi Arabia.;[El-Shorbagy, M. A.] Prince Sattam Bin Abdulaziz Univ, Coll Sci & Humanities Al Kharj, Dept Math, Al Kharj 11942, Saudi Arabia.;[El-Shorbagy, M. A.] Menoufia Univ, Fac Engn, Dept Basic Engn Sci, Shibin Al Kawm 32511, Egypt.
通讯机构:
[M. A. El-Shorbagy] D;[Muhammad Ibrahim] S;School of Mathematics and Physics, University of Science and Technology Beijing, Beijing, People’s Republic of China<&wdkj&>Department of Mathematics, College of Science and Humanities in Al-Kharj, Prince Sattam Bin Abdulaziz University, Al-Kharj, Saudi Arabia<&wdkj&>Department of Basic Engineering Science, Faculty of Engineering, Menoufia University, Shebin El-Kom, Egypt
摘要:
In this paper, the natural convection heat transfer of water/alumina nanofluid is investigated in a closed square cavity. An oblique magnetic field is applied on the cavity of angle $$\gamma$$ . There is also radiation heat transfer in the cavity. The cavity includes a high-temperature source of L-shape. A low-temperature source as a quadrant of a circle is placed at the corner of the cavity. All other walls are well insulated. The novelty of this work is a low-temperature obstacle embedded in the cavity. Simulations are conducted with a Fortran code based on the control volume method and simple algorithm. Entropy generation rate, Bejan number, and heat transfer are studied by changing different parameters. Results indicate that the highest rates of heat transfer and entropy generation have occurred for the perpendicular magnetic field at high values of the Rayleigh number. At these Rayleigh numbers, the minimum value of the Bejan number is obtained for 15° magnetic field. The magnetic field variation can lead to a change up to 53% in Nusselt number and up to 34% in generated entropy. In a weak magnetic field, the involvement of the radiation heat transfer mechanism leads to an increase in the heat transfer rate so that the Nusselt number can be increased by ten units considering the radiation heat transfer when there is no magnetic field. The maximum heat transfer rate occurs in the horizontal cavity and the minimum value in the cavity of 60° angle. For water, these values are 10.75 and 9.98 for 0 and 60 angles, respectively. Moreover, a weak magnetic field increases the heat transfer rate in the absence of the radiation mechanism, while it is reduced by considering a strong magnetic field.
期刊:
Journal of Molecular Liquids,2021年335:116137 ISSN:0167-7322
作者机构:
[Zhou, Shuang-Shuang] Hunan City Univ, Coll Sci, Yiyang 413000, Peoples R China.;[Almarashi, Adel] Jazan Univ, Coll Sci, Dept Math, Post Box 2097,New Campus, Jazan, Saudi Arabia.;[Dara, Rebwar Nasir] Salahaddin Univ Erbil, Coll Sci, Dept Geol, Erbil, Iraq.;[Dara, Rebwar Nasir] Knowledge Univ, Coll Engn, Dept Petr Engn, Erbil, Kurdistan Regio, Iraq.;[Issakhov, Alibek] Al Farabi Kazakh Natl Univ, Dept Math & Comp Modeling, Alma Ata, Kazakhstan.
关键词:
Magnetic force;Permeable space;Convection;Hybrid nano powder
摘要:
Complex cavity permeated with permeable media was influenced by magnetic field in current modeling. The flow encounters resistance in existence of Lorentz force and to improve thermal features, water was equipped with nano powders. Induce magnetic was ignored and to harness the permeability effect, non-Darcy approach was used. Current model acquired large attention in industry. For examine the correctness of code, the results of 0 was compared with previous basic article and achieved graph illustrates nice conformity of current modeling. Two straight wall were adiabatic, lower and upper walls were confined to hot and cold temperature bath. Laminar flow was established and maximum of Ra is 10(5) and carrier fluid is incompressible. To incorporate the gravity force, Boussinesq principle was utilized. The bottom surface was subjected to hot source and gravity enforces the nanomaterial to go up and create rotating cell. The complex shape of isotherms pertains to stronger convection which is attributed to greater permeability. Involve of MHD, declines the distortion of isotherms and conduction becomes stronger in greater Ha. Rise of Ha leads to decrease in Psi about 60% when Da = 100. Psi augments about 100% with augment of Da when Ha = 0. Rise of Ha provides reduction in Nu about 11.48% and 9.37% when Da = 100 and 0.01, respectively. Rise of Rd offers 106.6% augmentation in Nu when Ha = 0. When Ha = 20 and Da = 100, rise of Ra leads to 99% augmentation in Nu. (C) 2021 Elsevier B.V. All rights reserved.
作者:
Zhang, Xiao-Hong;Abidi, Awatef;Ahmed, A. El-Sayed;Khan, M. Riaz;El-Shorbagy, M. A.;...
期刊:
Case Studies in Thermal Engineering,2021年26 ISSN:2214-157X
通讯作者:
Khan, M.R.
作者机构:
[Zhang, Xiao-Hong] Hunan City Univ, Coll Sci, Yiyang 413000, Peoples R China.;[Abidi, Awatef] King Khalid Univ, Coll Sci Abha, Phys Dept, Abha, Saudi Arabia.;[Abidi, Awatef] Monastir Univ, Energy Engn Dept, Natl Engn Sch, Res Lab Metrol & Energy Syst, Monastir City, Tunisia.;[Abidi, Awatef] Sousse Univ, Higher Sch Sci & Technol Hammam Sousse, Sousse, Tunisia.;[Ahmed, A. El-Sayed] Taif Univ, Fac Sci, Math Dept, POB 11099, At Taif 21944, Saudi Arabia.