Xionglve Li¹, Junhua Xi¹, Zhiping Cai^1,*, Tao Yang¹, Chak Fong Cheang²

CMC-Computers, Materials & Continua, Vol.59, No.3, pp. 955-964, 2019, DOI:10.32604/cmc.2019.05769

Abstract The research and analysis of Internet topology is hot in the field of network measurement, which have important applications in network security, traffic scheduling and many other fields. Most of the existing works are focused on the AS-level and router-level topology, but few works are about the IP-level topology. In fact, obtaining the topology of each continent and knowing how the topologies of the continents are connected to each other can help us understanding the Internet around the world more thoroughly. In this paper, we obtained data sets from RIPE, constructed and analyzed network topologies More >

Yonghong Zhang^1,*, Yunfei Deng¹, Yunping Liu¹, Lihua Wang¹

CMC-Computers, Materials & Continua, Vol.59, No.3, pp. 833-851, 2019, DOI:10.32604/cmc.2019.04078

Abstract In the transition mode of quad tilt wing-unmanned aerial vehicle (QTW-UAV), the system stability of UAV will change with the tilt angle changes, which will cause serious head drop down. Meanwhile, with the complex air flow and other disturbances, the system is prone to side bias, frying, stall and other kinetic stability problems, hence the system stability analysis has become an urgent problem to be solved. To solve the stability problem, we need the quantitative criteria of system stability and effective tool of stability analysis, and can improve the stability of the motion control by… More >

Sultan Noman Qasem^1,2, Amar Nazar³, Attia Qamar⁴, Shahaboddin Shamshirband^5,6,*, Ahmad Karim⁴

CMC-Computers, Materials & Continua, Vol.59, No.3, pp. 713-727, 2019, DOI:10.32604/cmc.2019.05617

Abstract Brain tumor is one of the most dangerous disease that causes due to uncontrollable and abnormal cell partition. In this paper, we have used MRI brain scan in comparison with CT brain scan as it is less harmful to detect brain tumor. We considered watershed segmentation technique for brain tumor detection. The proposed methodology is divided as follows: pre-processing, computing foreground applying watershed, extract and supply features to machine learning algorithms. Consequently, this study is tested on big data set of images and we achieved acceptable accuracy from K-NN classification algorithm in detection of brain More >

Zhiguo Qu^1,*, Shengyao Wu², Wenjie Liu¹, Xiaojun Wang³

CMC-Computers, Materials & Continua, Vol.59, No.2, pp. 607-624, 2019, DOI:10.32604/cmc.2019.02656

Abstract In the field of quantum communication, quantum steganography is an important branch of quantum information hiding. In a realistic quantum communication system, quantum noises are unavoidable and will seriously impact the safety and reliability of the quantum steganographic system. Therefore, it is very important to analyze the influence of noise on the quantum steganography protocol and how to reduce the effect of noise. This paper takes the quantum steganography protocol proposed in 2010 as an example to analyze the effects of noises on information qubits and secret message qubits in the four primary quantum noise More >

Dae-Young Kim¹, Seokhoon Kim^2,*

CMC-Computers, Materials & Continua, Vol.59, No.2, pp. 375-387, 2019, DOI:10.32604/cmc.2019.06077

Abstract Communication is important for providing intelligent services in connected vehicles. Vehicles must be able to communicate with different places and exchange information while driving. For service operation, connected vehicles frequently attempt to download large amounts of data. They can request data downloading to a road side unit (RSU), which provides infrastructure for connected vehicles. The RSU is a data bottleneck in a transportation system because data traffic is concentrated on the RSU. Therefore, it is not appropriate for a connected vehicle to always attempt a high speed download from the RSU. If the mobile network… More >

Yuhan Kang¹, Fenlin Liu¹, Chunfang Yang^1,*, Xiangyang Luo¹, Tingting Zhang²

CMC-Computers, Materials & Continua, Vol.59, No.1, pp. 315-329, 2019, DOI:10.32604/cmc.2019.05242

Abstract This study proposes a color image steganalysis algorithm that extracts high-dimensional rich model features from the residuals of channel differences. First, the advantages of features extracted from channel differences are analyzed, and it shown that features extracted in this manner should be able to detect color stego images more effectively. A steganalysis feature extraction method based on channel differences is then proposed, and used to improve two types of typical color image steganalysis features. The improved features are combined with existing color image steganalysis features, and the ensemble classifiers are trained to detect color stego More >

Filipe L. A. Ribeiro^1,*, Andre R. Barbosa², Luis C. Neves³

CMES-Computer Modeling in Engineering & Sciences, Vol.120, No.3, pp. 657-676, 2019, DOI:10.32604/cmes.2019.06296

Abstract Although pre-Northridge earthquake steel moment resisting frame buildings have been shown to be susceptible to brittle connection failures, they still represent a large fraction of the existing steel buildings in the United States of America. In this study, the performance of the 3- and 9-story Los Angeles pre-Northridge SAC buildings are analyzed considering ductile and brittle beam-column connection failures, and their uncertainty. This paper contributes to understanding the influence of uncertainty associated with connections brittle fracture on building interstory deformation capacity and its impact on bias and variability of fragility functions and loss assessment. The More >

Tuanjie Li^1,*, Yan Zhang¹, Jiaxing Zhou¹

CMES-Computer Modeling in Engineering & Sciences, Vol.118, No.3, pp. 583-598, 2019, DOI:10.31614/cmes.2018.04891

Abstract In order to satisfy the high efficiency and high precision of collaborative robots, this work presents a novel trajectory planning method. First, in Cartesian space, a novel velocity look-ahead control algorithm and a cubic polynomial are combined to construct the end-effector trajectory of robots. Then, the joint trajectories can be obtained through the inverse kinematics. In order to improve the smoothness and stability in joint space, the joint trajectories are further adjusted based on the velocity look-ahead control algorithm and quintic B-spline. Finally, the proposed trajectory planning method is tested on a 4-DOF serial collaborative More >

Gongyu Hou¹, Zhedong Xu^1,*, Xin Liu¹, Cong Jin¹

CMES-Computer Modeling in Engineering & Sciences, Vol.118, No.2, pp. 317-337, 2019, DOI:10.31614/cmes.2019.04693

Abstract This article proposes an exponential adjustment inertia weight immune particle swarm optimization (EAIW-IPSO) to enhance the accuracy and reliability regarding the selection of shield tunneling parameter values. According to the iteration changes and the range of inertia weight in particle swarm optimization algorithm (PSO), the inertia weight is adjusted by the form of exponential function. Meanwhile, the self-regulation mechanism of the immune system is combined with the PSO. 12 benchmark functions and the realistic cases of shield tunneling parameter value selection are utilized to demonstrate the feasibility and accuracy of the proposed EAIW-IPSO algorithm. Comparison More >

Abdulkadir Karaci^1,*, Hasbi Yaprak², Osman Ozkaraca³, Ilhami Demir⁴, Osman Simsek⁵

CMES-Computer Modeling in Engineering & Sciences, Vol.118, No.1, pp. 207-228, 2019, DOI:10.31614/cmes.2019.04216

Abstract In this study, deep-neural-network (DNN)- and artificial-neural-network (ANN)-based models along with regression models have been developed to estimate the pressure, bending and elongation values of ground-brick (GB)-added mortar samples. This study is aimed at utilizing GB as a mineral additive in concrete in the ratios 0.0%, 2.5%, 5.0%, 7.5%, 10.0%, 12.5% and 15.0%. In this study, 756 mortar samples were produced for 84 different series and were cured in tap water (W), 5% sodium sulphate solution (SS5) and 5% ammonium nitrate solution (AN5) for 7 days, 28 days, 90 days and 180 days. The developed… More >