Lina Shi¹, Zichi Wang¹, Zhenxing Qian^1,*, Nannan Huang¹, Pauline Puteaux², Xinpeng Zhang¹

CMC-Computers, Materials & Continua, Vol.59, No.3, pp. 943-953, 2019, DOI:10.32604/cmc.2019.05768

Abstract Nowadays, emoji image is widely used in social networks. To achieve covert communication in emoji images, this paper proposes a distortion function for emoji images steganography. The profile of image content, the intra- and inter-frame correlation are taken into account in the proposed distortion function to fit the unique properties of emoji image. The three parts are combined together to measure the risks of detection due to the modification on the cover data. With the popular syndrome trellis coding (STC), the distortion of stego emoji image is minimized using the proposed distortion function. As a More >

Wengui Su^1,2, Xiang Wang^3,*, Yulong Shen¹

CMC-Computers, Materials & Continua, Vol.59, No.3, pp. 925-941, 2019, DOI:10.32604/cmc.2019.04842

Abstract With the reversible data hiding method based on pixel-value-ordering, data are embedded through the modification of the maximum and minimum values of a block. A significant relationship exists between the embedding performance and the block size. Traditional pixel-value-ordering methods utilize pixel blocks with a fixed size to embed data; the smaller the pixel blocks, greater is the embedding capacity. However, it tends to result in the deterioration of the quality of the marked image. Herein, a novel reversible data hiding method is proposed by incorporating a block merging strategy into Li et al.’s pixel-value-ordering method,… More >

Yong Xie¹, Fang Xu², Xiang Li¹, Songsong Zhang¹, Xiaodan Zhang^1,*, Muhammad Israr³

CMC-Computers, Materials & Continua, Vol.59, No.3, pp. 903-924, 2019, DOI:10.32604/cmc.2019.05309

Abstract Wireless sensor networks (WSNs) are the major contributors to big data acquisition. The authenticity and integrity of the data are two most important basic requirements for various services based on big data. Data aggregation is a promising method to decrease operation cost for resource-constrained WSNs. However, the process of data acquisitions in WSNs are in open environments, data aggregation is vulnerable to more special security attacks with hiding feature and subjective fraudulence, such as coalition attack. Aimed to provide data authenticity and integrity protection for WSNs, an efficient and secure identity-based aggregate signature scheme (EIAS) More >

Yujie Zhang¹, Genlin Ji^1,*, Bin Zhao¹, Bo Sheng²

CMC-Computers, Materials & Continua, Vol.59, No.3, pp. 885-901, 2019, DOI:10.32604/cmc.2019.05612

Abstract The discovery of gradual moving object clusters pattern from trajectory streams allows characterizing movement behavior in real time environment, which leverages new applications and services. Since the trajectory streams is rapidly evolving, continuously created and cannot be stored indefinitely in memory, the existing approaches designed on static trajectory datasets are not suitable for discovering gradual moving object clusters pattern from trajectory streams. This paper proposes a novel algorithm of gradual moving object clusters pattern discovery from trajectory streams using sliding window models. By processing the trajectory data in current window, the mining algorithm can capture More >

Xinyan Wang^1,*, Minjun Zhang², Zengwang Lu³

CMC-Computers, Materials & Continua, Vol.59, No.3, pp. 873-883, 2019, DOI:10.32604/cmc.2019.05230

Abstract Multi-tag collision imposes a vital detrimental effect on reading performance of an RFID system. In order to ameliorate such collision problem and to improve the reading performance, this paper proposes an efficient tag identification algorithm termed as the Enhanced Adaptive Tree Slotted Aloha (EATSA). The key novelty of EATSA is to identify the tags using grouping strategy. Specifically, the whole tag set is divided into groups by a frame of size F. In cases multiple tags fall into a group, the tags of the group are recognized by the improved binary splitting (IBS) method whereas the More >

Zejun Han¹, Hongyuan Fang^2,3,4,*, Juan Zhang⁵, Fuming Wang^2,3,4

CMC-Computers, Materials & Continua, Vol.59, No.3, pp. 853-871, 2019, DOI:10.32604/cmc.2019.03839

Abstract The pavement layered structures are composed of surface layer, road base and multi-layered soil foundation. They can be undermined over time by repeated vehicle loads. In this study, a hybrid numerical method which can evaluate the displacement responses of pavement structures under dynamic falling weight deflectometer (FWD) loads. The proposed method consists of two parts: (a) the dynamic stiffness matrices of the points at the surface in the frequency domain which is based on the domain-transformation and dual vector form equation, and (b) interpolates the dynamic stiffness matrices by a continues rational function of frequency. More >

Wentao Zhao¹, Pan Li^1,*, Chengzhang Zhu^1,2, Dan Liu¹, Xiao Liu¹

CMC-Computers, Materials & Continua, Vol.59, No.3, pp. 817-832, 2019, DOI:10.32604/cmc.2019.05957

Abstract The defense techniques for machine learning are critical yet challenging due to the number and type of attacks for widely applied machine learning algorithms are significantly increasing. Among these attacks, the poisoning attack, which disturbs machine learning algorithms by injecting poisoning samples, is an attack with the greatest threat. In this paper, we focus on analyzing the characteristics of positioning samples and propose a novel sample evaluation method to defend against the poisoning attack catering for the characteristics of poisoning samples. To capture the intrinsic data characteristics from heterogeneous aspects, we first evaluate training data More >

Murat Cancan^{1, *}

CMC-Computers, Materials & Continua, Vol.59, No.3, pp. 777-786, 2019, DOI:10.32604/cmc.2019.06596

Abstract Topological indices enable to gather information for the underlying topology of chemical structures and networks. Novel harmonic indices have been defined recently. All degree based topological indices are defined by using the classical degree concept. Recently two novel degree concept have been defined in graph theory: ve-degree and ev-degree. Ve-degree Zagreb indices have been defined by using ve-degree concept. The prediction power of the ve-degree Zagreb indices is stronger than the classical Zagreb indices. Dominating oxide, silicate and oxygen networks are important network models in view of chemistry, physics and information science. Physical and mathematical More >

Mohammed Omari^1,*, Souleymane Ouled Jaafri¹

CMC-Computers, Materials & Continua, Vol.59, No.3, pp. 753-775, 2019, DOI:10.32604/cmc.2019.06576

Abstract Image compression is a process based on reducing the redundancy of the image to be stored or transmitted in an efficient form. In this work, a new idea is proposed, where we take advantage of the redundancy that appears in a group of images to be all compressed together, instead of compressing each image by itself. In our proposed technique, a classification process is applied, where the set of the input images are classified into groups based on existing technique like L₁ and L₂ norms, color histograms. All images that belong to the same group are 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 >