Chia-Nan Wang, Thuy-Duong Thi Pham^*, Nhat-Luong Nhieu

Energy Engineering, Vol.121, No.8, pp. 2039-2064, 2024, DOI:10.32604/ee.2024.050224

Abstract Geothermal energy is considered a renewable, environmentally friendly, especially carbon-free, sustainable energy source that can solve the problem of climate change. In general, countries with geothermal energy resources are the ones going through the ring of fire. Therefore, not every country is lucky enough to own this resource. As a country with 117 active volcanoes and within the world’s ring of fire, it is a country whose geothermal resources are estimated to be about 40% of the world’s geothermal energy potential. However, the percentage used compared to the geothermal potential is too small. Therefore, this… More >

Tiezhou Wu, Yukan Zhang^*

Energy Engineering, Vol.121, No.8, pp. 2231-2255, 2024, DOI:10.32604/ee.2024.049883

Abstract In order to solve the problem of inconsistent energy in the charging and discharging cycles of lithium-ion battery packs, a new multilayer equilibrium topology is designed in this paper. The structure adopts a hierarchical structure design, which includes intra-group equilibrium, primary inter-group equilibrium and secondary inter-group equilibrium. This structure greatly increases the number of equilibrium paths for lithium-ion batteries, thus shortening the time required for equilibrium, and improving the overall efficiency. In terms of control strategy, fuzzy logic control (FLC) is chosen to control the size of the equilibrium current during the equilibrium process. We… More >

Yirui Li¹, Dongliang Xiao^1,3,*, Haoyong Chen¹, Weijun Cai¹, Josue Campos do Prado²

Energy Engineering, Vol.121, No.8, pp. 2093-2127, 2024, DOI:10.32604/ee.2024.049232

Abstract Currently, both regulated and deregulated power trading exist in China’s power system, which has caused imbalanced funds in the electricity market. In this paper, a simulation analysis of the electricity market with wind energy resources is conducted, and the calculation methods of unbalanced funds are investigated systematically. In detail, the calculation formulas of unbalanced funds are illustrated based on their definition, and a two-track electricity market clearing model is established. Firstly, the concept of the dual-track system is explained, and the specific calculation formulas of various types of unbalanced funds are provided. Next, considering the More >

He Li¹, Xianchao Liu^2,*, Jidong Li¹, Yuchen Qiu²

Energy Engineering, Vol.121, No.8, pp. 2293-2311, 2024, DOI:10.32604/ee.2024.048752

Abstract When employing stepwise inertial control (SIC), wind power generation can offer significant frequency support to the power system, concurrently mitigating energy shortages and suppressing secondary frequency drop. Nonetheless, further investigation is imperative for implementing stepped inertia control due to variations in frequency regulation capabilities and operational safety among diverse wind farm groups. Consequently, this paper advocates a multi-wind farm ladder timing SIC method designed to alleviate secondary drops in system frequency. Initially, the paper introduces the fundamental principles of stepped inertia control for a doubly-fed induction generator (DFIG) and deduces the relationship between support energy,… More >

Mingguan Zhao^1,4, Lida Liao^2,*, Penglong Liang¹, Meng Li¹, Xinsheng Dong¹, Yang Yang¹, Hongxia Wang¹, Zhenhao Zhang³

Energy Engineering, Vol.121, No.8, pp. 2313-2330, 2024, DOI:10.32604/ee.2024.048261

Abstract The rapid growth of distributed renewable energy penetration is promoting the evolution of the energy system toward decentralization and decentralized and digitized smart grids. This study was based on energy blockchain, and developed a dual-biding mechanism based on the real-time energy surplus and demand in the local smart grid, which is expected to enable reliable, affordable, and clean energy supply in smart communities. In the proposed system, economic benefits could be achieved by replacing fossil-fuel-based electricity with the high penetration of affordable solar PV electricity. The reduction of energy surplus realized by distributed energy production More >

Retno Asih^1,*, Haniffudin Nurdiansah², Mochamad Zainuri¹, Deni S. Khaerudini^3,4, Angelinus T. Setiawan⁴, A. Y. Dias⁴, Pudji Untoro^4,5, Ahmad Sholih¹, Darminto^1,*

Journal of Renewable Materials, Vol.12, No.5, pp. 969-979, 2024, DOI:10.32604/jrm.2024.049097

Abstract Biomass has become of recent interest as a raw material for ‘green’ graphenic carbon (GC) since it promotes an environmentally friendly approach. Here, we investigate a single pyrolysis route to synthesize GC from coconut shells which provides a simple method and can produce a high yield, thus being convenient for large-scale production. The pyrolysis involves a stepped holding process at 350°C for 1 h and at 650°C or 900°C for 3 h. The GC sample resulted at the 900°C pyrolysis has a thinner sheet, a less porous structure, a higher C/O ratio, and an enhanced More > Graphic Abstract

Ponusa Songtipya^1,2,*, Thummanoon Prodpran^1,2, Ladawan Songtipya^1,2, Theerarat Sengsuk¹

Journal of Renewable Materials, Vol.12, No.5, pp. 951-967, 2024, DOI:10.32604/jrm.2024.049068

Abstract The synergistic effect of organoclay (OC) and zinc oxide (ZnO) nanoparticles on the crucial properties of poly(lactic acid) (PLA) nanocomposite films was systematically investigated herein. After their incorporation into PLA via the solvent casting technique, the water vapor barrier property of the PLA/OC/ZnO film improved by a maximum of 86% compared to the neat PLA film without the deterioration of Young’s modulus or the tensile strength. Moreover, the film’s self-antibacterial activity against foodborne pathogens, including gram-negative (Escherichia coli, E. coli) and gram-positive (Staphylococcus aureus, S. aureus) bacteria, was enhanced by a maximum of approximately 98–99% compared to the neat… More > Graphic Abstract

Ambika Aggarwal¹, Sunil Kumar^2,3, Ashok Bhansali⁴, Deema Mohammed Alsekait^5,*, Diaa Salama AbdElminaam^6,7,8

Computer Systems Science and Engineering, Vol.48, No.4, pp. 953-967, 2024, DOI:10.32604/csse.2024.050406

Abstract Existing multiple workflow scheduling techniques focus on traditional Quality of Service (QoS) parameters such as cost, deadline, and makespan to find optimal solutions by consuming a large amount of electrical energy. Higher energy consumption decreases system efficiency, increases operational cost, and generates more carbon footprint. These major problems can lead to several problems, such as economic strain, environmental degradation, resource depletion, energy dependence, health impacts, etc. In a cloud computing environment, scheduling multiple workflows is critical in developing a strategy for energy optimization, which is an NP-hard problem. This paper proposes a novel, bi-phase Energy-Efficient… More >

Jiawei Qin^1,2, Hua Zhang^1,*, Hanbing Yan², Tian Zhu², Song Hu¹, Dingyu Yan²

Intelligent Automation & Soft Computing, Vol.39, No.3, pp. 527-544, 2024, DOI:10.32604/iasc.2024.047509

Abstract By the analysis of vulnerabilities of Android native system services, we find that some vulnerabilities are caused by inconsistent data transmission and inconsistent data processing logic between client and server. The existing research cannot find the above two types of vulnerabilities and the test cases of them face the problem of low coverage. In this paper, we propose an extraction method of test cases based on the native system services of the client and design a case construction method that supports multi-parameter mutation based on genetic algorithm and priority strategy. Based on the above method, More >

Xiaojun Li, Fuyong Su^*

Frontiers in Heat and Mass Transfer, Vol.22, No.3, pp. 719-732, 2024, DOI:10.32604/fhmt.2024.051950

Abstract In order to study the effect of oxygen-enriched combustion technology on the temperature field and NO emission in the continuous heating furnace, this paper studies the oxygen-enriched combustion of a pushing steel continuous heating furnace in a domestic company. This study utilizes numerical simulation method, establishes the mathematical models of flow, combustion and NO generation combustion process in the furnace and analyzes the heat transfer process and NO generation in the furnace under different air oxygen content and different wind ratio. The research results show that with the increase of oxygen content in the air, More > Graphic Abstract