Qin Yao, Yida Zeng^*, Qingui Jia

Energy Engineering, Vol.121, No.1, pp. 221-241, 2024, DOI:10.32604/ee.2023.041028

Abstract In recent years, switched inductor (SL) technology, switched capacitor (SC) technology, and switched inductor-capacitor (SL-SC) technology have been widely applied to optimize and improve DC-DC boost converters, which can effectively enhance voltage gain and reduce device stress. To address the issue of low output voltage in current renewable energy power generation systems, this study proposes a novel non-isolated cubic high-gain DC-DC converter based on the traditional quadratic DC-DC boost converter by incorporating a SC and a SL-SC unit. Firstly, the proposed converter’s details are elaborated, including its topology structure, operating mode, voltage gain, device stress, and power loss. Subsequently, a… More >

Yuqin Wang^1,2,3,*, Luxiang Zhou³, Mengle Han¹, Lixiang Shen¹

FDMP-Fluid Dynamics & Materials Processing, Vol.19, No.9, pp. 2215-2228, 2023, DOI:10.32604/fdmp.2023.027188

Abstract The main structural parameters of the IR100-80-100A type chemical centrifugal pump have been optimized by means of an orthogonal test approach. The centrifugal pump has been modeled using the CFturbo software, and 16 sets of orthogonal-test schemes have been defined on the basis of 4 parameters, namely, the blade number, blade outlet angle, impeller outlet diameter, and impeller outlet width. Such analysis has been used to determine the influence of each index parameter on the pump working efficiency and identify a set of optimal combinations of such parameters. The internal flow field in the centrifugal pump has been simulated by… More > Graphic Abstract

Wajdi Elhamzi^1,2,*, Malika Jallouli³, Yassine Bouteraa^1,4

CMC-Computers, Materials & Continua, Vol.73, No.2, pp. 4329-4347, 2022, DOI:10.32604/cmc.2022.030954

Abstract Since 3D mesh security has become intellectual property, 3D watermarking algorithms have continued to appear to secure 3D meshes shared by remote users and saved in distant multimedia databases. The novelty of our approach is that it uses a new Clifford-multiwavelet transform to insert copyright data in a multiresolution domain, allowing us to greatly expand the size of the watermark. After that, our method does two rounds of insertion, each applying a different type of Clifford-wavelet transform. Before being placed into the Clifford-multiwavelet coefficients, the watermark, which is a mixture of the mesh description, source mesh signature (produced using SHA512),… More >

Kun-Lin Tsai^1,2,*, Li-Woei Chen³, Fang-Yie Leu^4,5, Chuan-Tian Wu¹

CMC-Computers, Materials & Continua, Vol.73, No.1, pp. 547-562, 2022, DOI:10.32604/cmc.2022.026557

Abstract Secure data communication is an essential requirement for an Internet of Things (IoT) system. Especially in Industrial Internet of Things (IIoT) and Internet of Medical Things (IoMT) systems, when important data are hacked, it may induce property loss or life hazard. Even though many IoT-related communication protocols are equipped with secure policies, they still have some security weaknesses in their IoT systems. LoRaWAN is one of the low power wide-area network protocols, and it adopts Advanced Encryption Standard (AES) to provide message integrity and confidentiality. However, LoRaWAN's encryption key update scheme can be further improved. In this paper, a Two-stage… More >

Muhammad Arslan Usman¹, Muhammad Rehan Usman², Gandeva Bayu Satrya³, Muhammad Ashfaq Khan⁴, Christos Politis¹, Nada Philip¹, Soo Young Shin^5,*

CMC-Computers, Materials & Continua, Vol.67, No.2, pp. 1697-1712, 2021, DOI:10.32604/cmc.2021.014696

Abstract With the advent in services such as telemedicine and telesurgery, provision of continuous quality monitoring for these services has become a challenge for the network operators. Quality standards for provision of such services are application specific as medical imagery is quite different than general purpose images and videos. This paper presents a novel full reference objective video quality metric that focuses on estimating the quality of wireless capsule endoscopy (WCE) videos containing bleeding regions. Bleeding regions in gastrointestinal tract have been focused in this research, as bleeding is one of the major reasons behind several diseases within the tract. The… More >

Anudeep Gandam^1,*, Jagroop Singh Sidhu²

CMC-Computers, Materials & Continua, Vol.66, No.3, pp. 3045-3063, 2021, DOI:10.32604/cmc.2021.013663

Abstract In-loop filtering significantly helps detect and remove blocking artifacts across block boundaries in low bitrate coded High Efficiency Video Coding (HEVC) frames and improves its subjective visual quality in multimedia services over communication networks. However, on faster processing of the complex videos at a low bitrate, some visible artifacts considerably degrade the picture quality. In this paper, we proposed a four-step fuzzy based adaptive deblocking filter selection technique. The proposed method removes the quantization noise, blocking artifacts and corner outliers efficiently for HEVC coded videos even at low bit-rate. We have considered Y (luma), U (chroma-blue), and V (chroma-red) components… More >

Naeem Ahmad Jan¹, Saad Hassan Kiani², Daniyal Ali Sehrai², Muhammad Rizwan Anjum³, Amjad Iqbal⁴, Mujeeb Abdullah⁵, Sunghwan Kim^6,*

CMC-Computers, Materials & Continua, Vol.66, No.1, pp. 35-44, 2021, DOI:10.32604/cmc.2020.012800

Abstract In this paper, a low cost, highly efficient and low profile monopole antenna for ultra-wideband (UWB) applications is presented. A new inverted triangular-shape structure possessing meander lines is designed to achieve a wideband response and high efficiency. To design the proposed structure, three steps are utilized to achieve an UWB response. The bandwidth of the proposed antenna is improved with changing meander lines parameters, miniaturization of the ground width and optimization of the feeding line. The measured and simulated frequency band ranges from 3.2 to 12 GHz, while the radiation patterns are measured at 4, 5.3, 6 and 8 GHz… 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 robot. The experimental results indicate… More >