Xiuqing Qian¹, Yanping Cao², Jianyu Zhang¹, Dierk Raabe², Zhenhan Yao³, Binjun Fei¹

CMC-Computers, Materials & Continua, Vol.7, No.1, pp. 33-42, 2008, DOI:10.3970/cmc.2008.007.033

Abstract In this work, an inverse approach based on depth-sensing instrumented indentation tests is proposed to determine the Young's modulus, yield strength and strain hardening exponent of the materials for which the elastoplastic part of the stress-strain curve can be described using a power function. Numerical verifications performed on typical engineering metals demonstrate the effectiveness of the new method. The sensitivity of the method to data noise and some experimental uncertainties are also discussed, which may provide useful information for the application of the method in practice. More >

B. Srivathsa¹, N. Ramakrishnan²

CMC-Computers, Materials & Continua, Vol.7, No.1, pp. 9-24, 2008, DOI:10.3970/cmc.2008.007.009

Abstract An analytical model, describing an explosive compaction process performed axially on a powder assembly of cylindrical geometry, is discussed. The powder is encapsulated in a cylindrical metal container surrounded by an explosive pad, which is detonated parallel to the major axis of the compact. The pressure generated in the powder is a function of the nature and the thickness of the explosive material as well as the powder characteristics. The model is based on the principle of shock propagation in powder aggregate and, the detonation as well as the refraction wave characteristics of the explosives. For the purpose of validation… More >

Yueping Wang^1,*, Xuan Zhang², Yixuan Zhang³

CMC-Computers, Materials & Continua, Vol.61, No.1, pp. 171-184, 2019, DOI:10.32604/cmc.2019.06204

Abstract Full-duplex (FD) has been recognized as a promising technology for future 5G networks to improve the spectrum efficiency. However, the biggest practical impediments of realizing full-duplex communications are the presence of self-interference, especially in complex cellular networks. With the current development of self-interference cancellation techniques, full-duplex has been considered to be more suitable for device-to-device (D2D) and small cell communications which have small transmission range and low transmit power. In this paper, we consider the full-duplex D2D communications in multi-tier wireless networks and present an analytical model which jointly considers mode selection, resource allocation, and power control. Specifically, we consider… More >

Yueyun Chen^1,*, Zhuo Zeng¹, Taohua Chen¹, Zushen Liu², Alan Yang³

CMC-Computers, Materials & Continua, Vol.60, No.2, pp. 835-853, 2019, DOI:10.32604/cmc.2019.07080

Abstract The communication reliability and system capacity are two of the key performance indicators for Internet of Vehicles (IoV). Existing studies have proposed a variety of technologies to improve reliability and other performance, such as channel selection and power allocation in Vehicle-to-Infrastructure (V2I). However, these researches are mostly applied in a single roadside unit (RSU) scenario without considering inter-cell interference (ICI) of multi-RSUs. In this paper, considering the distribution characteristics of multi-RSUs deployment and corresponding ICI, we propose a reliable uplink transmission scheme to maximize the total capacity and decrease the interference of multi-RSUs (mRSU-DI) in condition of the uplink interruption… More >

Yongbin Zhao^1,*, XuYang¹, RanranLi¹

CMC-Computers, Materials & Continua, Vol.58, No.2, pp. 517-527, 2019, DOI:10.32604/cmc.2019.03680

Abstract Stream ciphers based on linear feedback shift register (LFSR) are suitable for constrained environments, such as satellite communications, radio frequency identification devices tag, sensor networks and Internet of Things, due to its simple hardware structures, high speed encryption and lower power consumption. LFSR, as a cryptographic primitive, has been used to generate a maximum period sequence. Because the switching of the status bits is regular, the power consumption of the LFSR is correlated in a linear way. As a result, the power consumption characteristics of stream cipher based on LFSR are vulnerable to leaking initialization vectors under the power attacks.… More >

Leiting Dong^1,2, Robert Haynes³, Satya N. Atluri²

CMC-Computers, Materials & Continua, Vol.45, No.1, pp. 1-16, 2015, DOI:10.3970/cmc.2015.045.001

Abstract In this study, we propose to approximate the a－n relation as well as the da/dn－∆K relation, in fatigue crack propagation, by using the Moving Least Squares (MLS) method. This simple approach can avoid the internal inconsistencies caused by the celebrated Paris’ power law approximation of the da/dn－∆K relation, as well as the error caused by a simple numerical differentiation of the noisy data for a－n measurements in standard fatigue tests. Efficient, accurate and automatic simulations of fatigue crack propagation can, in general, be realized by using the currently developed MLS law as the “fatigue engine” [da/dn versus ∆K], and using… More >

X. Frank Xu^1,2, Yuxin Jie³, Irene J. Beyerlein⁴

CMC-Computers, Materials & Continua, Vol.38, No.1, pp. 17-30, 2013, DOI:10.3970/cmc.2013.038.017

Abstract This note aims to relate the measured strength statistics of individual carbon nanotubes (CNTs) to the physics of brittle fracture and the weakest link model. By approximating an arbitrary flaw size distribution with a segmented power law, an effort is made to extend applicability of the Weibull distribution to arbitrary flaw populations, which explains why the Weibull distribution fits the experimental data of CNTs and many other brittle materials, and why in other cases it is not so clear. A generalized Weibull distribution is proposed to account for all non-asymptotic cases. The published CNT testing data are analyzed, and finally… More >

CMC-Computers, Materials & Continua, Vol.18, No.3, pp. 271-300, 2010, DOI:10.3970/cmc.2010.018.271

Abstract The processing maps are a superimposition of iso-efficiency contour map and flow instability map, which are used to design hot working processing conditions in a wide variety of materials. In order to construct the processing maps, the efficiency of power dissipation and an instability criterion taking into account the contribution of strain and microstructure evolution are proposed based on a set of microstructure-based viscoplastic constitutive equations. In viscoplastic constitutive equations, the grain size of matrix phase and the dislocation density are taken as internal state variables. And, the material constants in present equations can be identified by a genetic algorithm… More >

Deepak A Apte¹, Ranjan Ganguli^1,2

CMC-Computers, Materials & Continua, Vol.10, No.2, pp. 139-162, 2009, DOI:10.3970/cmc.2009.010.139

Abstract The influence of electric field and temperature on power consumption of piezoelectric actuated integrated structure is studied by using a single degree of freedom mass-spring-damper system model coupled with a piezoactuator. The material lead zirconate titanate, is considered as it is capable of producing relatively high strains (e.g., 3000με). Actuators are often subject to high electric fields to increase the induced strain produced, resulting in field dependant piezoelectric coefficient d₃₁, dielectric coefficient ε₃₃ and dissipation factor δ. Piezostructures are also likely to be used across a wide range of temperatures in aerospace and undersea operations. Again, the piezoelectric properties can… More >