Zhengtao Liu^1,*, Jinyue Xia²

CMC-Computers, Materials & Continua, Vol.60, No.1, pp. 395-408, 2019, DOI:10.32604/cmc.2019.05627

Abstract Tenants in the cloud computing environment share various services, including storage, network, computing, and applications. For better use of services in the cloud computing environment, tenants collaborate in tasks, resulting in challenges to the traditional access control. This study proposes a cross-tenant role-based access control (CT-RBAC) model for collaborative cloud services. This model covers the CT-RBAC0, CT-RBAC1, CT-RBAC2, and CT-RBAC3 models. The model not only extends the RBAC model in the multi-tenant cloud computing mode but also includes four types of authorization modes among tenants. Consequently, the role inheritance constraint is increased, and fine-grained authorization access among trusted tenants is… More >

Jun Xie¹, Dapeng Sun¹, Jiaxiang Cai², Fuhong Cai^1,*

CMC-Computers, Materials & Continua, Vol.59, No.2, pp. 687-695, 2019, DOI:10.32604/cmc.2019.03658

Abstract The level of chemical oxygen demand (COD) is an important index to evaluate whether sewage meets the discharge requirements, so corresponding tests should be carried out before discharge. Fourier transform infrared spectroscopy (FTIR) and attenuated total reflectance (ATR) can detect COD in sewage effectively, which has advantages over conventional chemical analysis methods. And the selection of characteristic bands was one of the key links in the application of FTIR/ATR spectroscopy. In this work, based on the moving window partial least-squares (MWPLS) regression to select a characteristic wavelength, a method of equivalent wavelength selection was proposed combining with paired t-test equivalent… More >

X. Han^1,2,3, G. R. Liu^1,2, G. Y. Li ¹

CMC-Computers, Materials & Continua, Vol.1, No.1, pp. 39-50, 2004, DOI:10.3970/cmc.2004.001.039

Abstract An efficient hybrid numerical method is presented for investigating transient response of cross-ply laminated axisymmetric cylinders subjected to an impact load. In this hybrid numerical method, the laminated cylinder is divided into layered cylindrical elements in the thickness direction. The Hamilton principle is used to develop governing equations of the structure. The displacement response is determined by employing the Fourier transformations and the modal analysis. Numerical examples for analyzing transient waves have been provided in axisymmetric laminated cylindrical structures, both for thin cylindrical shells and thick cylinders.
A computational inverse technique is also presented for reconstructing elastic constants of… More >

Donggang Li^1,2, Alexandra Levesque², Qiang Wang^1,3,2, Agnieszka Franczak², Chun Wu¹, Jean-Paul Chopart², Jicheng He¹

CMC-Computers, Materials & Continua, Vol.30, No.3, pp. 207-218, 2012, DOI:10.3970/cmc.2012.030.207

Abstract Co/Ni bilayered films were prepared on ITO glass by electrodeposition assisted with a magnetic field up to 0.5T aligned parallel to the electrode surface. The effect of a high magnetic field annealing up to 12T on morphology and microstructure of the post-deposited films was investigated by field emission scanning electronic microscopy (FE-SEM), X-ray diffraction (XRD) and atomic force microscopy (AFM). Grain shape and grain boundary in the Co/Ni morphology were modified dramatically when the high magnetic field was applied during the annealing process. Magnetic anisotropy appeared in the films due to the preferential orientation of fcc-CoNi alloy in comparison with… More >

E. Ferretti¹, M.C. Bignozzi²

CMC-Computers, Materials & Continua, Vol.27, No.3, pp. 231-274, 2012, DOI:10.3970/cmc.2011.027.231

Abstract In this study, the results of an in-situ experimental program on the performance of concrete taxiways are presented. The experimental program has been undertaken at the Guglielmo Marconi airport of Bologna (Italy). It concerns two portions of the taxiway, one built with plain concrete and one with rubberized concrete. Each portion has been instrumented with strain gauges embedded in concrete for the acquisition of vertical strains. The results of the experimentation are discussed in view of possible applications to the computational analysis of the stress field induced into pavements by aircrafts. More >

Deli Gao¹, Zengxin Zhao²

CMC-Computers, Materials & Continua, Vol.26, No.2, pp. 157-166, 2011, DOI:10.3970/cmc.2011.026.157

Abstract The research on casing corrosion in sour environment by a synergism of sweet corrosion and H₂S corrosion has become the basis of casing selection and casing string safety evaluation with more and more sour reservoirs containing high H₂S concentration being developed. It is essential to scientifically utilize casing service ability and reasonably control production rate of gas well to achieve the effective and safe developing of gas resources during the safety period of casing service with a precise casing life prediction. Scanning electron microscopy and tensile testing were applied to investigate the corrosion of TP110TS tube steel in stimulant solution… More >

Zone-Ching Lin¹, Ying-Chih Hsu¹

CMC-Computers, Materials & Continua, Vol.25, No.1, pp. 75-106, 2011, DOI:10.3970/cmc.2011.025.075

Abstract The three-dimensional quasi-steady molecular statics nanocutting model is used by this paper to carry out simulation analysis of nanocutting of sapphire in order to explore the effects of conical tools with different tip radii of probe and straight-line cutting at different cutting depths, on cutting force. Meanwhile, this paper uses a cutting tool of atomic force microscopy (AFM) with a probe tip similar to a semisphere to conduct nanocutting experiment of sapphire substrate. Furthermore, from the experimental results of nanocutting sapphire substrate, this paper innovatively proposes the theoretical model and equation that the specific down force energy (SDFE) during nanocutting… More >

Hongbin Zhang^{1, 2}, Yuzi Yi^{1, *}, Junshe Wang¹, Ning Cao^{3, *}, Qiang Duan⁴

CMC-Computers, Materials & Continua, Vol.56, No.3, pp. 381-399, 2018, DOI: 10.3970/cmc.2018.03787

Abstract Network security situation awareness is an important foundation for network security management, which presents the target system security status by analyzing existing or potential cyber threats in the target system. In network offense and defense, the network security state of the target system will be affected by both offensive and defensive strategies. According to this feature, this paper proposes a network security situation awareness method using stochastic game in cloud computing environment, uses the utility of both sides of the game to quantify the network security situation value. This method analyzes the nodes based on the network security state of… More >

Zihao Yang¹, Junzhi Cui², Yufeng Nie¹, Yatao Wu¹, Bin Yang³, Bo Wu⁴

CMC-Computers, Materials & Continua, Vol.38, No.3, pp. 175-194, 2013, DOI:10.3970/cmc.2013.038.175

Abstract This study is concerned with the microstructural modeling and mechanical properties computation of three-dimensional (3D) 4-directional braided composites. Microstructure of the braided composite determines its mechanical properties and a precise geometry modeling of the composite is essential to predict the material properties. On the basis of microscopic observation, a new parameterized microstructural unit cell model is established in this paper. And this model truly simulates the microstructure of the braided composites. Furthermore, the mathematical relationships among the structural parameters, including the braiding angle, fiber volume fraction and braiding bitch, are derived. By using the unit cell model, the second-order two-scale… More >

Hsin-Yu Chen¹, Nien-Ti Tsou^1,*

CMES-Computer Modeling in Engineering & Sciences, Vol.120, No.2, pp. 319-332, 2019, DOI:10.32604/cmes.2019.06447

Abstract Shape memory alloys has been widely applied on actuators and medical devices. The transformation temperature and microstructural evolution play two crucial factors and dominate the behavior of shape memory alloys. In order to understand the influence of the composition of the Ni-Ti alloys on the two factors, molecular dynamics was adopted to simulate the temperature-induced phase transformation. The results were post-processed by the martensite variant identification method. The method allows to reveal the detailed microstructural evolution of variants/phases in each case of the composition of Ni-Ti. Many features were found and having good agreement with those reported in the literature,… More >