Chein-Shan Liu¹, Chih-Wen Chang²

CMC-Computers, Materials & Continua, Vol.25, No.2, pp. 107-134, 2011, DOI:10.3970/cmc.2011.025.107

Abstract We consider two inverse problems for estimating radiative coefficients α(x) and α(x, y), respectively, in T_t(x, t) = T_xx(x, t)-α(x)T(x, t), and T_t(x, y, t) = T_xx(x, y, t) + T_yy(x, y, t)-α(x, y)T(x, y, t), where a are assumed to be continuous functions of space variables. A Lie-group adaptive method is developed, which can be used to find a at the spatially discretized points, where we only utilize the initial condition and boundary conditions, such as those for a typical direct problem. This point is quite different from other methods, which need the overspecified final time data. Three-fold advantages… 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 >

Yanzhong Wang¹, Xiangyu Wu^1,*

CMC-Computers, Materials & Continua, Vol.56, No.3, pp. 353-363, 2018, DOI: 10.3970/cmc.2018.03714

Abstract To investigate the effects of configuration parameters and operation condition on the thermal behavior of novel conical friction plate, a three-dimensional finite element model of conical friction plate is established for numerical simulation. The conical surface configuration and friction heat generation of novel conical friction surfaces are discussed. The results indicate that the thermal behavior of the conical friction plate during continuously sliding period is influenced by the conical surface configuration. Maximum temperature occurs in the conical friction plate with cone angle of 24°. The maximum temperature value of friction plate is increased 7.4°C, when cone depth increases from 3… More >

Zhiqiang Ruan^1,*, Haibo Luo¹, Wenzhong Lin¹, Jie Wang²

CMC-Computers, Materials & Continua, Vol.56, No.3, pp. 483-499, 2018, DOI: 10.3970/cmc.2018.03687

Abstract Content caching is a core component in Named Data Networking (NDN), where content is cached in routers and served for future requests. However, the adversary can launch verification attack by placing poisoned data into the network with a legitimate name and allow the routers in the delivery path to frequently identify the content. Since NDN employs digital signature on each piece of content, verifying all content will exhaust routers’ computational resources due to the massive data in the network. In this paper, we propose a selective verification scheme upon the contents that are hit in the content store and allow… More >

Yue Zhang¹, Dengpan Ye², Junjun Gan¹, Zhenyu Li³, Qingfeng Cheng^1,*

CMC-Computers, Materials & Continua, Vol.56, No.1, pp. 151-167, 2018, DOI: 10.3970/cmc.2018.02464

Abstract In view of the fact that the current adaptive steganography algorithms are difficult to resist scaling attacks and that a method resisting scaling attack is only for the nearest neighbor interpolation method, this paper proposes an image steganography algorithm based on quantization index modulation resisting both scaling attacks and statistical detection. For the spatial image, this paper uses the watermarking algorithm based on quantization index modulation to extract the embedded domain. Then construct the embedding distortion function of the new embedded domain based on S-UNIWARD steganography, and use the minimum distortion coding to realize the embedding of the secret messages.… More >

Zhiguo Qu^1,*, Tiancheng Zhu², Jinwei Wang¹, Xiaojun Wang³

CMC-Computers, Materials & Continua, Vol.56, No.1, pp. 47-59, 2018, DOI: 10.3970/cmc.2018.02215

Abstract In this paper, a novel quantum steganography protocol based on Brown entangled states is proposed. The new protocol adopts the CNOT operation to achieve the transmission of secret information by the best use of the characteristics of entangled states. Comparing with the previous quantum steganography algorithms, the new protocol focuses on its anti-noise capability for the phase-flip noise, which proved its good security resisting on quantum noise. Furthermore, the covert communication of secret information in the quantum secure direct communication channel would not affect the normal information transmission process due to the new protocol’s good imperceptibility. If the number of… More >

Chenpeng Song^1,2, Yulong Chen^3,*, Jiehao Wang^2,*

CMES-Computer Modeling in Engineering & Sciences, Vol.120, No.3, pp. 779-797, 2019, DOI:10.32604/cmes.2019.07000

Abstract Hydraulic fracturing has been applied to enhance CBM production and prevent gas dynamical hazard in underground coal mines in China. However, affected by in situ stress orientation, hydrofracture can hardly continuously propagate within coal seam but may easily extend to the adjacent roof-floor strata, causing ineffective permeability enhancement in coal seam and increasing the risk of gas transfinite during mining coal. Thus, it is very necessary to artificially control the propagation direction of hydrofracture and make it well-aligned in large scale in coal seam. In this study, a method for controlling propagation direction of hydrofracture by multi-boreholes is investigated by… More >

Yong Li^1,*, Joel P. Conte², Philip E. Gill³

CMES-Computer Modeling in Engineering & Sciences, Vol.120, No.3, pp. 517-543, 2019, DOI:10.32604/cmes.2019.06269

Abstract In the field of earthquake engineering, the advent of the performance-based design philosophy, together with the highly uncertain nature of earthquake ground excitations to structures, has brought probabilistic performance-based design to the forefront of seismic design. In order to design structures that explicitly satisfy probabilistic performance criteria, a probabilistic performance-based optimum seismic design (PPBOSD) framework is proposed in this paper by extending the state-of-the-art performance-based earthquake engineering (PBEE) methodology. PBEE is traditionally used for risk evaluation of existing or newly designed structural systems, thus referred to herein as forward PBEE analysis. In contrast, its use for design purposes is limited… More >

R. Agalya¹, R. Muthaiah^2,*, D. Muralidharan³

CMES-Computer Modeling in Engineering & Sciences, Vol.120, No.1, pp. 25-43, 2019, DOI:10.32604/cmes.2019.05616

Abstract In today’s modern design technology, post-silicon validation is an expensive and composite task. The major challenge involved in this method is that it has limited observability and controllability of internal signals. There will be an issue during execution how to address the useful set of signals and store it in the on-chip trace buffer. The existing approaches are restricted to particular debug set-up where all the components have equivalent prominence at all the time. Practically, the verification engineers will emphasis only on useful functional regions or components. Due to some constraints like clock gating, some of the regions can be… More >

Sahib Khan^1,*, M A Irfan¹, Arslan Arif¹, Syed Tahir Hussain Rizvi², Asma Gul³, Muhammad Naeem⁴, Nasir Ahmad⁵

CMES-Computer Modeling in Engineering & Sciences, Vol.118, No.3, pp. 529-546, 2019, DOI:10.31614/cmes.2019.06179

Abstract This work presents a new method of data hiding in digital images, in discrete cosine transform domain. The proposed method uses the least significant bits of the medium frequency components of the cover image for hiding the secret information, while the low and high frequency coefficients are kept unaltered. The unaltered low frequency DCT coefficients preserves the quality of the smooth region of the cover image, while no changes in the high DCT coefficient preserve the quality of the edges. As the medium frequency components have less contribution towards energy and image details, so the modification of these coefficients for… More >