S. Guenoun¹, A. Baïri¹, N. Laraqi^1,2, J.M. García de María³, J.G. Bauzin¹, A. Hocine¹

FDMP-Fluid Dynamics & Materials Processing, Vol.8, No.2, pp. 197-214, 2012, DOI:10.3970/fdmp.2012.008.197

Abstract Roller bearings are used in mechanical setups to reduce rubbing. In some applications, the thermal dissipation involved mostly due to friction between rollers and rings is important. Correct operation of the roller is possible only if local thermal phenomena are controlled. In this work, the resulting dynamical and thermal fields within the enclosures limited by rollers and rings in cylindrical bearings are obtained through numerical modelling. Convective heat transfer is quantified by Nu-Re-Pr correlations for various dynamical and thermal configurations of the bearing. Two specific shape factors of the cavity and common fluids of engineering interest are considered, including air,… More >

Joseph G. Lawrence, Arunan Nadarajah¹

FDMP-Fluid Dynamics & Materials Processing, Vol.3, No.3, pp. 247-254, 2007, DOI:10.3970/fdmp.2007.003.247

Abstract A simplified 2D pseudo steady state model was developed for an atmospheric chemical vapor deposition (CVD) process on glass. This is used to study the feasibility of converting a continuous coating process to one with discrete glass plates with a gap between them. A preliminary estimate employing mass transfer correlations suggested that there would be significant concentration variations due to the gap between the plates. More detailed studies were done by solving the model numerically employing a finite difference scheme with a vorticity-stream function formulation, and employing the commercial computational fluid dynamics program FIDAP which employs a finite element scheme.… More >

Aurora Costales¹, C. J. F. Solano², E. Francisco¹, A. Martín Pendás¹

CMC-Computers, Materials & Continua, Vol.38, No.2, pp. 105-128, 2013, DOI:10.3970/cmc.2013.038.105

Abstract An extension of our previously reported periodic cluster model (J. Phys. Chem. C 2008, 112, 6667-6676 ) to nanorings and nanobelts is presented. This new scheme allows for accurately calculating reasonably large nanostructures while preserving a very small number of optimization parameters. The model has been applied to a number of AlN semiconducting structures using ab initio pair potentials. Attention has been paid to the variation of the B1-B4 phase transition pressure as the the size of the structures is varied. More >

S. Marguet¹, P. Rozycki¹, L. Gornet¹

CMC-Computers, Materials & Continua, Vol.4, No.3, pp. 119-136, 2006, DOI:10.3970/cmc.2006.004.119

Abstract This paper deals with the modelling until rupture of composite structures made of glass-fibre / epoxy-resin woven fabrics submitted to dynamic loadings. The model is built at the mesoscale of the elementary ply. It takes into account the slightly nonlinear brittle behaviour of the fibres under tensile sollicitations, their nonlinear behaviour in compression as well as the strongly non linear and irreversible behaviour of the ply in shear. Strain rate effects are also introduced and special attention is paid to the objectivity of the model in the context of finite element calculation. Therefore the choice of a delayed damage mesomodel… More >

Afzal Badshah¹, Anwar Ghani¹, Muhammad Ahsan Qureshi², Shahaboddin Shamshirband,^3,4,*

CMC-Computers, Materials & Continua, Vol.61, No.1, pp. 81-101, 2019, DOI:10.32604/cmc.2019.06288

Abstract Educational institutions are soft targets for the terrorist with massive and defenseless people. In the recent past, numbers of such attacks have been executed around the world. Conducting research, in order to provide a secure environment to the educational institutions is a challenging task. This effort is motivated by recent assaults, made at Army Public School Peshawar, following another attack at Charsada University, Khyber Pukhtun Khwa, Pakistan and also the Santa Fe High School Texas, USA massacre. This study uses the basic technologies of edge computing, cloud computing and IoT to design a smart emergency alarm system framework. IoT is… More >

V. Gowrishankar^1,*, K. Venkatachalam¹

CMC-Computers, Materials & Continua, Vol.60, No.3, pp. 947-957, 2019, DOI:10.32604/cmc.2019.07749

Abstract A high precision 10-bit successive approximation register analog to digital converter (ADC) designed and implemented in 32nm CNTFET process technology at the supply of 0.6V, with 73.24 dB SNDR at a sampling rate of 640 MS/s with the average power consumption of 120.2 μW for the Internet of things node. The key components in CNTFET SAR ADCs are binary scaled charge redistribution digital to analog converter using MOS capacitors, CNTFET based dynamic latch comparator and simple SAR digital code error correction logic. These techniques are used to increase the sampling rate and precision while ensuring the linearity, power consumption and… More >

Lei Xu¹, Chungen Xu^1,*, Zhongyi Liu¹, Yunling Wang^2,3, Jianfeng Wang^2,3

CMC-Computers, Materials & Continua, Vol.60, No.2, pp. 675-690, 2019, DOI:10.32604/cmc.2019.05276

Abstract With the rapid development of cloud computing and Internet of Things (IoT) technology, massive data raises and shuttles on the network every day. To ensure the confidentiality and utilization of these data, industries and companies users encrypt their data and store them in an outsourced party. However, simple adoption of encryption scheme makes the original lose its flexibility and utilization. To address these problems, the searchable encryption scheme is proposed. Different from traditional encrypted data search scheme, this paper focuses on providing a solution to search the data from one or more IoT device by comparing their underlying numerical values.… More >

Baowei Wang^1,2,*, Weiwen Kong¹, Wei Li¹, Neal N. Xiong³

CMC-Computers, Materials & Continua, Vol.58, No.3, pp. 679-695, 2019, DOI:10.32604/cmc.2019.06106

Abstract Chaining watermark is an effective way to verify the integrity of streaming data in wireless network environment, especially in resource-constrained sensor networks, such as the perception layer of Internet of Things applications. However, in all existing single chaining watermark schemes, how to ensure the synchronization between the data sender and the receiver is still an unsolved problem. Once the synchronization points are attacked by the adversary, existing data integrity authentication schemes are difficult to work properly, and the false negative rate might be up to 50 percent. And the additional fixed group delimiters not only increase the data size, but… More >

Jin Wang^1,2,3, Yu Gao³, Wei Liu³, Wenbing Wu¹, Se-Jung Lim^4,*

CMC-Computers, Materials & Continua, Vol.58, No.3, pp. 711-725, 2019, DOI:10.32604/cmc.2019.05450

Abstract Recently, Wireless sensor networks (WSNs) have become very popular research topics which are applied to many applications. They provide pervasive computing services and techniques in various potential applications for the Internet of Things (IoT). An Asynchronous Clustering and Mobile Data Gathering based on Timer Mechanism (ACMDGTM) algorithm is proposed which would mitigate the problem of “hot spots” among sensors to enhance the lifetime of networks. The clustering process takes sensors’ location and residual energy into consideration to elect suitable cluster heads. Furthermore, one mobile sink node is employed to access cluster heads in accordance with the data overflow time and… More >

Chunhua Li^1,*, Peng Wang¹, Changhong Sun¹, Ke Zhou¹, Ping Huang²

CMC-Computers, Materials & Continua, Vol.58, No.2, pp. 319-333, 2019, DOI:10.32604/cmc.2019.03856

Abstract The security of cloud data has always been a concern. Cloud server provider may maliciously tamper or delete user’s data for their own benefit, so data integrity audit is of great significance to verify whether data is modified or not. Based on the general three-party audit architecture, a dynamic auditing scheme without bilinear pairings is proposed in this paper. It utilizes exponential operation instead of bilinear mapping to verify the validity of evidence. By establishing the mapping relation between logic index and tag index of data block with index transformation table, our scheme can easily support dynamic data operation. By… More >