Wenhua Liu^a,b, Mo Yang^c,a,*, Yuwen Zhang^b , Guiliang Liu^a , Liang Ling^a , Xuchen Ying^a,*

Frontiers in Heat and Mass Transfer, Vol.20, pp. 1-7, 2023, DOI:10.5098/hmt.20.15

Abstract In this study, numerical investigations are performed on a partially premixed flame of methane and air in two- and three-dimensional models. Nonlinear method is adopted to illustrate the asymmetric phenomenon that affects the flame stability under various co-flow velocities. According to the results, the mathematical relationship between the flame flickering frequency Stanton number and the dimensionless velocity Froude number has been summarized as St=0.7Fr^-0.46. The bifurcation phenomena under different Reynold numbers are found to have significant influence on the system stability. Two critical bifurcation points, which is when Re=300 and Re=1200, are determined as the onset of breaking the flame… More >

Bareen Shamsaldeen Tahir¹, Zainab Salih Ageed², Sheren Sadiq Hasan³, Subhi R. M. Zeebaree^4,*

CMC-Computers, Materials & Continua, Vol.75, No.2, pp. 4009-4024, 2023, DOI:10.32604/cmc.2023.037433

Abstract Traditional indoor human activity recognition (HAR) is a time-series data classification problem and needs feature extraction. Presently, considerable attention has been given to the domain of HAR due to the enormous amount of its real-time uses in real-time applications, namely surveillance by authorities, biometric user identification, and health monitoring of older people. The extensive usage of the Internet of Things (IoT) and wearable sensor devices has made the topic of HAR a vital subject in ubiquitous and mobile computing. The more commonly utilized inference and problem-solving technique in the HAR system have recently been deep learning (DL). The study develops… More >

T. Haritha, A. Anitha^*

CMC-Computers, Materials & Continua, Vol.75, No.2, pp. 3923-3939, 2023, DOI:10.32604/cmc.2023.036278

Abstract In crowded cities, searching for the availability of parking lots is a herculean task as it results in the wastage of drivers’ time, increases air pollution, and traffic congestion. Smart parking systems facilitate the drivers to determine the information about the parking lot in real time and book them depending on the requirement. But the existing smart parking systems necessitate the drivers to reveal their sensitive information that includes their mobile number, personal identity, and desired destination. This disclosure of sensitive information makes the existing centralized smart parking systems more vulnerable to service providers’ security breaches, single points of failure,… More >

Ali Arshad^1,*, Muhammad Nadeem², Saman Riaz¹, Syeda Wajiha Zahra², Ashit Kumar Dutta³, Zaid Alzaid⁴, Rana Alabdan⁵, Badr Almutairi⁶, Sultan Almotairi^4,7

CMC-Computers, Materials & Continua, Vol.75, No.2, pp. 3065-3089, 2023, DOI:10.32604/cmc.2023.035695

Abstract There are many cloud data security techniques and algorithms available that can be used to detect attacks on cloud data, but these techniques and algorithms cannot be used to protect data from an attacker. Cloud cryptography is the best way to transmit data in a secure and reliable format. Various researchers have developed various mechanisms to transfer data securely, which can convert data from readable to unreadable, but these algorithms are not sufficient to provide complete data security. Each algorithm has some data security issues. If some effective data protection techniques are used, the attacker will not be able to… More >

Aisha Fayomi¹, Christophe Chesneau^2,*, Farrukh Jamal³, Ali Algarni¹

CMES-Computer Modeling in Engineering & Sciences, Vol.136, No.3, pp. 2371-2403, 2023, DOI:10.32604/cmes.2023.027000

Abstract In this article, we highlight a new three-parameter heavy-tailed lifetime distribution that aims to extend the modeling possibilities of the Lomax distribution. It is called the extended Lomax distribution. The considered distribution naturally appears as the distribution of a transformation of a random variable following the logweighted power distribution recently introduced for percentage or proportion data analysis purposes. As a result, its cumulative distribution has the same functional basis as that of the Lomax distribution, but with a novel special logarithmic term depending on several parameters. The modulation of this logarithmic term reveals new types of asymetrical shapes, implying a… More >

Roudouane Laouar^1,*, Olaf Wünsch²

FDMP-Fluid Dynamics & Materials Processing, Vol.19, No.4, pp. 1055-1066, 2023, DOI:10.32604/fdmp.2022.022677

Abstract In this work, a parametric two-dimensional computational fluid dynamics (CFD) analysis of a solar chimney power plant (a prototype located in Manzanares, Spain) is presented to illustrate the effects of the solar radiation mode in the collector on the plant performances. The simulations rely on a mathematical model that includes solar radiation within the collector; energy storage; air flow and heat transfer, and a turbine. It is based on the Navier-Stokes equation for turbulent flow formulated according to the standard k-ε model. Moreover, the Boussinesq approach is used to account for the fluid density variations. Different solar radiation modes in… More >

Muhammad Nadeem¹, Ali Arshad^2,*, Saman Riaz², Syeda Wajiha Zahra¹, Ashit Kumar Dutta³, Moteeb Al Moteri⁴, Sultan Almotairi⁵

CMC-Computers, Materials & Continua, Vol.74, No.2, pp. 4059-4079, 2023, DOI:10.32604/cmc.2023.032882

Abstract Many symmetric and asymmetric encryption algorithms have been developed in cloud computing to transmit data in a secure form. Cloud cryptography is a data encryption mechanism that consists of different steps and prevents the attacker from misusing the data. This paper has developed an efficient algorithm to protect the data from invaders and secure the data from misuse. If this algorithm is applied to the cloud network, the attacker will not be able to access the data. To encrypt the data, the values of the bytes have been obtained by converting the plain text to ASCII. A key has been… More >

Muhammad Nadeem¹, Ali Arshad², Saman Riaz², Syeda Wajiha Zahra¹, Shahab S. Band³, Amir Mosavi^4,5,6,*

CMC-Computers, Materials & Continua, Vol.74, No.2, pp. 2625-2640, 2023, DOI:10.32604/cmc.2023.030899

Abstract Many organizations have insisted on protecting the cloud server from the outside, although the risks of attacking the cloud server are mostly from the inside. There are many algorithms designed to protect the cloud server from attacks that have been able to protect the cloud server attacks. Still, the attackers have designed even better mechanisms to break these security algorithms. Cloud cryptography is the best data protection algorithm that exchanges data between authentic users. In this article, one symmetric cryptography algorithm will be designed to secure cloud server data, used to send and receive cloud server data securely. A double… More >

Quanchun Yan^1,2,*, Chao Yuan¹, Wen Gu¹, Yanan Liu¹, Yiming Tang¹

Energy Engineering, Vol.120, No.1, pp. 49-68, 2023, DOI:10.32604/ee.2022.018555

Abstract In order to solve the problems of rotor overvoltage, overcurrent and DC side voltage rise caused by grid voltage drops, a coordinated control strategy based on symmetrical and asymmetrical low voltage ride through of rotor side converter of the doubly-fed generator is proposed. When the power grid voltage drops symmetrically, the generator approximate equation under steady-state conditions is no longer applicable. Considering the dynamic process of stator current excitation, according to the change of stator flux and the depth of voltage drop, the system can dynamically provide reactive power support for parallel nodes and suppress the rise of DC side… More >

Peng Wang¹, Yulu Tian², Bolong Men^1,*, Hailong Song¹

Intelligent Automation & Soft Computing, Vol.36, No.1, pp. 83-95, 2023, DOI:10.32604/iasc.2023.027602

Abstract Here the estimating problem of a single sinusoidal signal in the additive symmetric α-stable Gaussian (ASαSG) noise is investigated. The ASαSG noise here is expressed as the additive of a Gaussian noise and a symmetric α-stable distributed variable. As the probability density function (PDF) of the ASαSG is complicated, traditional estimators cannot provide optimum estimates. Based on the Metropolis-Hastings (M-H) sampling scheme, a robust frequency estimator is proposed for ASαSG noise. Moreover, to accelerate the convergence rate of the developed algorithm, a new criterion of reconstructing the proposal covariance is derived, whose main idea is updating the proposal variance using… More >