Xin Gu², Lin Wang^{1, 2, 3}, Fuyong Chen², Hongrui Li², Wengang Zhang^{1, 2, 3, ∗}

CMC-Computers, Materials & Continua, Vol.63, No.1, pp. 263-281, 2020, DOI:10.32604/cmc.2020.07535 - 30 March 2020

Abstract Temporal variation of rock mass properties, especially the strength degradation due to drying-wetting cycles as well as the acidic wetting fluid (rainfall or reservoir water) is crucial to stability of reservoir rock slopes. Based on a series of drying-wetting cycling and experiments considering the influences of pH values, the degradation degree models of the reduced cohesion c′, friction angle φ′ are developed. 2D stability analysis of the slope is subsequently carried out to calculate the factor of safety (Fs) via limit equilibrium method (LEM) and a predictive model of Fs is built using multivariate adaptive regression… More >

Binjie Gu^{1, *}, Weili Xiong¹, Zhonghu Bai²

CMC-Computers, Materials & Continua, Vol.63, No.1, pp. 243-262, 2020, DOI:10.32604/cmc.2020.06898 - 30 March 2020

Abstract Human action recognition under complex environment is a challenging work. Recently, sparse representation has achieved excellent results of dealing with human action recognition problem under different conditions. The main idea of sparse representation classification is to construct a general classification scheme where the training samples of each class can be considered as the dictionary to express the query class, and the minimal reconstruction error indicates its corresponding class. However, how to learn a discriminative dictionary is still a difficult work. In this work, we make two contributions. First, we build a new and robust human More >

Shuyu Li¹, Guozheng Zhang^{1, *}

CMC-Computers, Materials & Continua, Vol.63, No.1, pp. 223-241, 2020, DOI:10.32604/cmc.2020.07499 - 30 March 2020

Abstract With the popularity of sensor-rich mobile devices, mobile crowdsensing (MCS) has emerged as an effective method for data collection and processing. However, MCS platform usually need workers’ precise locations for optimal task execution and collect sensing data from workers, which raises severe concerns of privacy leakage. Trying to preserve workers’ location and sensing data from the untrusted MCS platform, a differentially private data aggregation method based on worker partition and location obfuscation (DP-DAWL method) is proposed in the paper. DP-DAWL method firstly use an improved K-means algorithm to divide workers into groups and assign different… More >

Shuzhuang Zhang¹, Hao Luo¹, Zhigang Wu¹, Yanbin Sun^{2, *}, Yuhang Wang², Tingting Yuan³

CMC-Computers, Materials & Continua, Vol.63, No.1, pp. 213-222, 2020, DOI:10.32604/cmc.2020.07496 - 30 March 2020

Abstract With the rapid increase of link speed and network throughput in recent years, much more attention has been paid to the work of obtaining statistics over speed traffic streams. It is a challenging problem to identify heavy hitters in high-speed and dynamically changing data streams with less memory and computational overhead with high measurement accuracy. In this paper, we combine Bloom Filter with exponential histogram to query streams in the sliding window so as to identify heavy hitters. This method is called EBF sketches. Our sketch structure allows for effective summarization of streams over time-based More >

Yinghua Zhang^{1, 2}, Jian Liu^{1, *}, Yunfeng Peng¹, Yanfang Dong², Guozhong Sun², Hao Huang³, Changming Zhao^{4, 5}

CMC-Computers, Materials & Continua, Vol.63, No.1, pp. 197-212, 2020, DOI:10.32604/cmc.2020.07059 - 30 March 2020

Abstract This paper proposes a hybrid spectrum accessing mechanism by using NOMA-based cooperative transmission and beam-forming technology. In this mechanism, the secondary user employs spectrum-sensing technology to detect the existence of the primary user. If the primary user does not exist, the secondary source user directly transmits data to the destination user. If the primary user exists, the secondary source user finds the optimal relay according to certain selection principle before transmitting data to the destination user through the chosen relay node. For the signal receiving stage, the secondary user takes use of beam-forming technology to More >

Ruohan Meng^{1, 2}, Qi Cui^{1, 2}, Zhili Zhou^{1, 2}, Chengsheng Yuan^{1, 2, 3}, Xingming Sun^{1, 2, *}

CMC-Computers, Materials & Continua, Vol.63, No.1, pp. 183-196, 2020, DOI:10.32604/cmc.2020.05317 - 30 March 2020

Abstract Information hiding tends to hide secret information in image area where is rich texture or high frequency, so as to transmit secret information to the recipient without affecting the visual quality of the image and arousing suspicion. We take advantage of the complexity of the object texture and consider that under certain circumstances, the object texture is more complex than the background of the image, so the foreground object is more suitable for steganography than the background. On the basis of instance segmentation, such as Mask R-CNN, the proposed method hides secret information into each More >

Xuefeng Xi¹, Victor S. Sheng^{1, 2, *}, Shuhui Yang³, Baochuan Fu¹, Zhiming Cui¹

CMC-Computers, Materials & Continua, Vol.63, No.1, pp. 163-181, 2020, DOI:10.32604/cmc.2020.06992 - 30 March 2020

Abstract The pattern of thematic progression, reflecting the semantic relationships between contextual two sentences, is an important subject in discourse analysis. We introduce a new corpus of Chinese news discourses annotated with thematic progression information and explore some computational methods to automatically extracting the discourse structural features of simplified thematic progression pattern (STPP) between contextual sentences in a text. Furthermore, these features are used in a hybrid approach to a major discourse analysis task, Chinese coreference resolution. This novel approach is built up via heuristic sieves and a machine learning method that comprehensively utilizes both the More >

Jing Li¹, Yong Yang^{2, *}, Hongmei Ge¹, Li Zhao³, Ruxue Guo^{3, 4}

CMC-Computers, Materials & Continua, Vol.63, No.1, pp. 151-162, 2020, DOI:10.32604/cmc.2020.05649 - 30 March 2020

Abstract Coal rock mass instability fracture may result in serious hazards to underground coal mining. Acoustic emissions (AE) stimulated by internal structure fracture should carry lots of favorable information about health condition of rock mass. AE as a sensitive non-destructive test method is gradually utilized to detect anomaly conditions of coal rock. This paper proposes an improved multi-resolution feature to extract AE waveform at different frequency resolutions using Coilflet Wavelet Transform method (CWT). It is further adopt an efficient Light Gradient Boosting Machine (LightGBM) by several cascaded sub weak classifier models to merge AE features at More >

Jieren Cheng^{1, 2}, Canting Cai^{1, *}, Xiangyan Tang¹, Victor S. Sheng³, Wei Guo¹, Mengyang Li¹

CMC-Computers, Materials & Continua, Vol.63, No.1, pp. 131-150, 2020, DOI:10.32604/cmc.2020.06175 - 30 March 2020

Abstract Traditional distributed denial of service (DDoS) detection methods need a lot of computing resource, and many of them which are based on single element have high missing rate and false alarm rate. In order to solve the problems, this paper proposes a DDoS attack information fusion method based on CNN for multi-element data. Firstly, according to the distribution, concentration and high traffic abruptness of DDoS attacks, this paper defines six features which are respectively obtained from the elements of source IP address, destination IP address, source port, destination port, packet size and the number of… More >

Jian Liu¹, Lei Wang¹, Changming Zhao^{2, 3, *}, Alan Yang⁴

CMC-Computers, Materials & Continua, Vol.63, No.1, pp. 119-130, 2020, DOI:10.32604/cmc.2020.06074 - 30 March 2020

Abstract In this paper, we consider a three-hop relay system based on interference cancellation technique in Underlay cognitive radio (CR) network. Although underlay CR has been shown as a promising technique to better utilize the source of primary users (PUs), its secondary performance will be severely degraded. On one hand, by adapting the Underlay spectrum sharing pattern, secondary users (SUs) would observe the strict power constraints and be interfered by primary users. On the other hand, limited transmit power results in limited transmission range, which greatly degrade the secondary transmission capacity. To solve the problems above, More >