Lejun Zhang^{1, 2}, Zhijie Zhang¹, Weizheng Wang³, Rasheed Waqas¹, Chunhui Zhao^{1, 4}, Seokhoon Kim⁵, Huiling Chen^{6, *}

CMC-Computers, Materials & Continua, Vol.65, No.1, pp. 597-616, 2020, DOI:10.32604/cmc.2020.011554

Abstract As an extension of the traditional encryption technology, information hiding has been increasingly used in the fields of communication and network media, and the covert communication technology has gradually developed. The blockchain technology that has emerged in recent years has the characteristics of decentralization and tamper resistance, which can effectively alleviate the disadvantages and problems of traditional covert communication. However, its combination with covert communication thus far has been mostly at the theoretical level. The BLOCCE method, as an early result of the combination of blockchain and covert communication technology, has the problems of low information embedding efficiency, the use… More >

Tao Zheng, Yan Chang, Shibin Zhang^*

CMES-Computer Modeling in Engineering & Sciences, Vol.124, No.2, pp. 573-584, 2020, DOI:10.32604/cmes.2020.010445

Abstract With the acceleration of the construction of quantum communication networks, scholars have proposed different quantum communication protocols for different application scenarios. However, few scholars pay attention to the risk assessment process before communication. In this paper, we propose a novel quantum risk assessment model based on quantum teleportation technology with two three-qubit GHZ states. Only by using Bell states measurements (BSMs) and two-qubit projective measurements (PJMs), the communicators can recovery any arbitrary two-qubit state. This protocol can transmit two-dimension risk assessment factors with better security performance. On the one hand, more sufficient evaluation factors allow the two communicating parties to… More >

Daniyal Ali Sehrai¹, Fazal Muhammad¹, Saad Hassan Kiani¹, Ziaul Haq Abbas², Muhammad Tufail³, Sunghwan Kim^{4, *}

CMC-Computers, Materials & Continua, Vol.64, No.3, pp. 1587-1599, 2020, DOI:10.32604/cmc.2020.011057

Abstract Metamaterial surfaces play a vital role to achieve the surface waves suppression and in-phase reflection, in order to improve the antenna performance. In this paper, the performance comparison of a fifth generation (5G) antenna design is analyzed and compared with a metamaterial-based antenna for 5G communication system applications. Metamaterial surface is utilized as a reflector due to its in-phase reflection characteristic and high-impedance nature to improve the gain of an antenna. As conventional conducting ground plane does not give enough surface waves suppression which affects the antenna performance in terms of efficiency and gain etc. These factors are well considered… More >

Xiaorong Zhao¹, Weili Cheng², Hongjin Zhu¹, Chunpeng Ge³, Gengyuan Zhou^{1, *}, Zhongjun Fu¹

CMC-Computers, Materials & Continua, Vol.64, No.2, pp. 1139-1151, 2020, DOI:10.32604/cmc.2020.010220

Abstract With the development of the times, people’s requirements for communication technology are becoming higher and higher. 4G communication technology has been unable to meet development needs, and 5G communication technology has emerged as the times require. This article proposes the design of a low-noise amplifier (LNA) that will be used in the 5G band of China Mobile Communications. A low noise amplifier for mobile 5G communication is designed based on Taiwan Semiconductor Manufacturing Company (TSMC) 0.13 μm Radio Frequency (RF) Complementary Metal Oxide Semiconductor (CMOS) process. The LNA employs self-cascode devices in currentreuse configuration to enable lower supply voltage operation… More >

Lisa X. Deng¹, Lacey P. Gleason², Katherine Awh², Abigail May Khan³, David Drajpuch^2,4, Stephanie Fuller⁵, Leah A. Goldberg², Christopher E. Mascio⁵, Sara L. Partington^2,4, Lynda Tobin^2,4, Adrienne H. Kovacs³, Yuli Y. Kim^2,4

Congenital Heart Disease, Vol.14, No.4, pp. 534-540, 2019, DOI:10.1111/chd.12778

Abstract Objective: To investigate the experiences and communication preferences of adult patients with congenital heart disease (CHD) in the domains of employment, insur‐ ance, and family planning.
Design: Patients ≥ 18 years of age completed a questionnaire about experiences and communication preferences regarding employment, health insurance, and family planning.
Results: Of 152 patients (median age = 33 years, 50% female, 35% with CHD of great complexity), one in four reported work‐related problems due to CHD and a quar‐ ter also recalled a previous gap in health insurance. Of females, 29% experienced an unplanned pregnancy. The median importance of discussion ratings (on… More >

Shahid Rahman¹, Fahad Masood², Wajid Ullah Khan², Niamat Ullah¹, Fazal Qudus Khan³, Georgios Tsaramirsis³, Sadeeq Jan^{4, *}, Majid Ashraf⁵

CMC-Computers, Materials & Continua, Vol.64, No.1, pp. 31-61, 2020, DOI:10.32604/cmc.2020.09186

Abstract Steganography aims to hide the messages from unauthorized persons for various purposes, e.g., military correspondence, financial transaction data. Securing the data during transmission is of utmost importance these days. The confidentiality, integrity, and availability of the data are at risk because of the emerging technologies and complexity in software applications, and therefore, there is a need to secure such systems and data. There are various methodologies to deal with security issues when utilizing an open system like the Internet. This research proposes a new technique in steganography within RGB shading space to achieve enhanced security compared with existing systems. We… More >

Seokhoon Kim¹, Dae-Young Kim^{2, *}

CMC-Computers, Materials & Continua, Vol.64, No.1, pp. 1-15, 2020, DOI:10.32604/cmc.2020.09545

Abstract The Internet of Things (IoT) has enabled various intelligent services, and IoT service range has been steadily extended through long range wide area communication technologies, which enable very long distance wireless data transmission. End-nodes are connected to a gateway with a single hop. They consume very low-power, using very low data rate to deliver data. Since long transmission time is consequently needed for each data packet transmission in long range wide area networks, data transmission should be efficiently performed. Therefore, this paper proposes a multicast uplink data transmission mechanism particularly for bad network conditions. Transmission delay will be increased if… More >

Yifei Wei^{1, *}, Yinxiang Qu¹, Min Zhao¹, Lianping Zhang², F. Richard Yu³

CMC-Computers, Materials & Continua, Vol.63, No.3, pp. 1515-1532, 2020, DOI:10.32604/cmc.2020.09130

Abstract Device-to-Device (D2D) communication is a promising technology that can reduce the burden on cellular networks while increasing network capacity. In this paper, we focus on the channel resource allocation and power control to improve the system resource utilization and network throughput. Firstly, we treat each D2D pair as an independent agent. Each agent makes decisions based on the local channel states information observed by itself. The multi-agent Reinforcement Learning (RL) algorithm is proposed for our multi-user system. We assume that the D2D pair do not possess any information on the availability and quality of the resource block to be selected,… More >

Lili Yan^{1, *}, Shibin Zhang¹, Yan Chang¹, Zhibin Sun², Zhiwei Sheng¹

CMC-Computers, Materials & Continua, Vol.63, No.3, pp. 1297-1307, 2020, DOI:10.32604/cmc.2020.09873

Abstract Quantum secure direct communication (QSDC) can transmit secret messages directly from one user to another without first establishing a shared secret key, which is different from quantum key distribution. In this paper, we propose a novel quantum secure direct communication protocol based on signal photons and Bell states. Before the execution of the proposed protocol, two participants Alice and Bob exchange their corresponding identity IDA and IDB through quantum key distribution and keep them secret, respectively. Then the message sender, Alice, encodes each secret message bit into two single photons (| 01〉or|10〉) or a Bell state , and composes… More >

Ahmed Y. Hamed¹, Monagi H. Alkinani², M. R. Hassan^{3, *}

CMC-Computers, Materials & Continua, Vol.63, No.3, pp. 1159-1173, 2020, DOI:10.32604/cmc.2020.09176

Abstract In the distributed networks, many applications send information from a source node to multiple destination nodes. To support these applications requirements, the paper presents a multi-objective algorithm based on ant colonies to construct a multicast tree for data transmission in a computer network. The proposed algorithm simultaneously optimizes total weight (cost, delay and hop) of the multicast tree. Experimental results prove the proposed algorithm outperforms a recently published Multi-objective Multicast Algorithm specially designed for solving the multicast routing problem. Also, it is able to find a better solution with fast convergence speed and high reliability. More >