Yonghui Lin¹, Zhengyu Zhu^2,*

CMES-Computer Modeling in Engineering & Sciences, Vol.138, No.1, pp. 663-677, 2024, DOI:10.32604/cmes.2023.028584

Abstract In this paper, we investigate IRS-aided user cooperation (UC) scheme in millimeter wave (mmWave) wireless-powered sensor networks (WPSN), where two single-antenna users are wireless powered in the wireless energy transfer (WET) phase first and then cooperatively transmit information to a hybrid access point (AP) in the wireless information transmission (WIT) phase, following which the IRS is deployed to enhance the system performance of the WET and WIT. We maximized the weighted sum-rate problem by jointly optimizing the transmit time slots, power allocations, and the phase shifts of the IRS. Due to the non-convexity of the original problem, a semidefinite programming… More >

Guobin He^*, Rui Su, Jinxin Yang, Yuanping Huang, Huanlin Chen, Donghui Zhang, Cangtao Yang, Wenwen Li

Energy Engineering, Vol.120, No.9, pp. 2133-2154, 2023, DOI:10.32604/ee.2023.029007

Abstract In the framework of vigorous promotion of low-carbon power system growth as well as economic globalization, multi-resource penetration in active distribution networks has been advancing fiercely. In particular, distributed generation (DG) based on renewable energy is critical for active distribution network operation enhancement. To comprehensively analyze the accessing impact of DG in distribution networks from various parts, this paper establishes an optimal DG location and sizing planning model based on active power losses, voltage profile, pollution emissions, and the economics of DG costs as well as meteorological conditions. Subsequently, multi-objective particle swarm optimization (MOPSO) is applied to obtain the optimal… More >

Jingxiao Han¹, Chuanzhao Zhang², Lu Wang^3,*, Zengjun Chang¹, Qing Zhao¹, Ying Shi⁴, Jiarui Wu⁵, Xiangfei Kong³

Energy Engineering, Vol.120, No.9, pp. 1991-2011, 2023, DOI:10.32604/ee.2023.029749

Abstract For heating systems based on electricity storage coupled with solar energy and an air source heat pump (ECSA), choosing the appropriate combination of heat sources according to local conditions is the key to improving economic efficiency. In this paper, four cities in three climatic regions in China were selected, namely Nanjing in the hot summer and cold winter region, Tianjin in the cold region, Shenyang and Harbin in the severe cold winter region. The levelized cost of heat (LCOH) was used as the economic evaluation index, and the energy consumption and emissions of different pollutants were analyzed. TRNSYS software was… More > Graphic Abstract

Nashat Salih Abdulkarim Alsandi¹, Dilovan Asaad Zebari^2,*, Adel Al-Zebari³, Falah Y. H. Ahmed⁴, Mazin Abed Mohammed⁵, Marwan Albahar⁶, Abdulaziz Ali Albahr^7,8

Computer Systems Science and Engineering, Vol.47, No.2, pp. 1321-1347, 2023, DOI:10.32604/csse.2023.038089

Abstract Information security has emerged as a key problem in encryption because of the rapid evolution of the internet and networks. Thus, the progress of image encryption techniques is becoming an increasingly serious issue and considerable problem. Small space of the key, encryption-based low confidentiality, low key sensitivity, and easily exploitable existing image encryption techniques integrating chaotic system and DNA computing are purposing the main problems to propose a new encryption technique in this study. In our proposed scheme, a three-dimensional Chen’s map and a one-dimensional Logistic map are employed to construct a double-layer image encryption scheme. In the confusion stage,… More >

Birgitta Svensson^1,2,*, Petru Liuba^1,2, Anne Wennick³, Malin Berghammer^4,5

Congenital Heart Disease, Vol.18, No.3, pp. 349-359, 2023, DOI:10.32604/chd.2023.028391

Abstract Background: Parents of children with complex right ventricular outflow tract (RVOT) anomalies are confronted with their child’s need for heart surgery early in life and repeated reoperations later on. Preoperative assessment needs to be performed whenever an indication for reoperation is suspected. The aim was to illuminate the experiences of parents of children diagnosed with RVOT anomalies, in particular, how they experience their child’s heart disease and everyday life during the assessment and after the decision on whether to perform a reoperation. Method: Individual interviews (n = 27) were conducted with nine parents on three occasions between 2014 and 2016 and analyzed… More >

Norman Aiad^1,2,3,7, Mark V. Sherrid^1,7, Adam J. Small¹, Youssef Elnabawi^1,7, Jodi Feinberg¹, Leon Axel^1,4, Ralph Mosca⁵, T. K. Susheel Kumar⁵, Michael Argilla⁶, Dan G. Halpern^1,7,*

Congenital Heart Disease, Vol.18, No.3, pp. 267-277, 2023, DOI:10.32604/chd.2023.025853

Abstract Introduction: We sought to investigate whether the development of sub-pulmonic systolic anterior motion (SAM) may be inherent to the anatomy of the the mitral valve (MV) or affected by external factors, such as a dilated right ventricle or chest abnormalities in d-looped transposition of the great arteries post atrial switch operation (d-TGA/AtS). Methods: Analysis was performed of clinical and cardiac imaging studies acquired on 19 adult patients with d-TGA/AtS (age 42 ± 6 years old, 56% male) between 2015–2019. Echocardiography data included mitral apparatus anatomy, and CT/MRI data included biventricular dimensions, function, and Haller index (HI) for pectus deformity. Results:… More >

Hassan Shokouhandeh¹, Mehrdad Ahmadi Kamarposhti^2,*, William Holderbaum³, Ilhami Colak⁴, Phatiphat Thounthong⁵

Computer Systems Science and Engineering, Vol.47, No.1, pp. 809-822, 2023, DOI:10.32604/csse.2023.035827

Abstract The widespread penetration of distributed energy sources and the use of load response programs, especially in a microgrid, have caused many power system issues, such as control and operation of these networks, to be affected. The control and operation of many small-distributed generation units with different performance characteristics create another challenge for the safe and efficient operation of the microgrid. In this paper, the optimum operation of distributed generation resources and heat and power storage in a microgrid, was performed based on real-time pricing through the proposed gray wolf optimization (GWO) algorithm to reduce the energy supply cost with the… More >

Zhedong Xu^*, Yongbo Su, Fang Yang, Ming Zhang

CMC-Computers, Materials & Continua, Vol.75, No.3, pp. 5965-5986, 2023, DOI:10.32604/cmc.2023.037611

Abstract Due to the development of digital transformation, intelligent algorithms are getting more and more attention. The whale optimization algorithm (WOA) is one of swarm intelligence optimization algorithms and is widely used to solve practical engineering optimization problems. However, with the increased dimensions, higher requirements are put forward for algorithm performance. The double population whale optimization algorithm with distributed collaboration and reverse learning ability (DCRWOA) is proposed to solve the slow convergence speed and unstable search accuracy of the WOA algorithm in optimization problems. In the DCRWOA algorithm, the novel double population search strategy is constructed. Meanwhile, the reverse learning strategy… More >

Xuehui Jing^a,* , Wei Li^a, Zhaoyu Li^a , Zhiyun Wang^b

Frontiers in Heat and Mass Transfer, Vol.20, pp. 1-4, 2023, DOI:10.5098/hmt.20.19

Abstract This paper numerically simulates the combustion in a 300MW tangentially fired pulverized high-alkali coal boiler under low-load conditions. The combustion process, temperature distribution and the thermal load in the furnace at different height are analyzed under three different load conditions, which are 30%, 45% and 60% of full load. The temperature distribution and the variation of NO_x concentration under different load conditions are investigated, as well. The results show that the combustion processes of pulverized high-alkali coal in the furnace are similar under different load conditions, but the positions of the fuel’s full combustion are related to the loads. With… More >

Zubing Tang^*

FDMP-Fluid Dynamics & Materials Processing, Vol.19, No.8, pp. 2161-2170, 2023, DOI:10.32604/fdmp.2023.026608

Abstract The mechanical behavior of the test string in deep wells is generally relatively complex as a result of the high temperature and high pressure, severe dogleg and buckling effects, which in some circumstances can even lead to string failure. Traditional computational methods for the analysis of these behaviors are often inaccurate. For this reason, here a more accurate mechanical model of the test string is introduced by considering variables such as temperature, pressure, wellbore trajectory, and buckling, as well as combining them with the deformation and string constraint conditions brought in by changes in temperature and pressure during the tripping,… More >