Cuiping Li¹, Kunqi Gao¹, Can Chen², Junhui Li^1,*, Xiaoxiao Wang², Yinchi Shao², Xingxu Zhu¹

Energy Engineering, Vol.121, No.10, pp. 2937-2959, 2024, DOI:10.32604/ee.2024.052167 - 11 September 2024

Abstract In recent years, distributed photovoltaics (DPV) has ushered in a good development situation due to the advantages of pollution-free power generation, full utilization of the ground or roof of the installation site, and balancing a large number of loads nearby. However, under the background of a large-scale DPV grid-connected to the county distribution network, an effective analysis method is needed to analyze its impact on the voltage of the distribution network in the early development stage of DPV. Therefore, a DPV orderly grid-connected method based on photovoltaics grid-connected order degree (PGOD) is proposed. This method… More >

Shengqiang Shi^1,2,*, Abdelatif Merabtine³, Rachid Bennacer⁴, Julien Kauffmann²

FDMP-Fluid Dynamics & Materials Processing, Vol.20, No.8, pp. 1703-1716, 2024, DOI:10.32604/fdmp.2024.050547 - 06 August 2024

Abstract At present, air handling units are usually used indoors to improve the indoor environment quality. However, while introducing fresh air to improve air quality, air velocity has a certain impact on the occupants’ thermal comfort. Therefore, it is necessary to explore the optimization of air-fluid-body interaction dynamics. In this study, the indoor air flow was changed by changing the opening and closing degree of the blower, and the thermal manikin is introduced to objectively evaluate the human thermal comfort under different air velocities. The main experimental results show that the air change rate increases with… More >

Chanho Park¹, Takefumi Ogawa^2,*

CMC-Computers, Materials & Continua, Vol.79, No.2, pp. 3047-3065, 2024, DOI:10.32604/cmc.2024.048901 - 15 May 2024

Abstract Six degrees of freedom (6DoF) input interfaces are essential for manipulating virtual objects through translation or rotation in three-dimensional (3D) space. A traditional outside-in tracking controller requires the installation of expensive hardware in advance. While inside-out tracking controllers have been proposed, they often suffer from limitations such as interaction limited to the tracking range of the sensor (e.g., a sensor on the head-mounted display (HMD)) or the need for pose value modification to function as an input interface (e.g., a sensor on the controller). This study investigates 6DoF pose estimation methods without restricting the tracking… More >

Zhiwei Lin¹, Hui Wang^1,*, Tianding Chen¹, Yingtao Jiang², Jianmei Jiang³, Yingpin Chen¹

CMES-Computer Modeling in Engineering & Sciences, Vol.139, No.2, pp. 1357-1379, 2024, DOI:10.32604/cmes.2023.045990 - 29 January 2024

Abstract In the domain of autonomous industrial manipulators, precise positioning and appropriate posture selection in path planning are pivotal for tasks involving obstacle avoidance, such as handling, heat sealing, and stacking. While Multi-Degree-of-Freedom (MDOF) manipulators offer kinematic redundancy, aiding in the derivation of optimal inverse kinematic solutions to meet position and posture requisites, their path planning entails intricate multi-objective optimization, encompassing path, posture, and joint motion optimization. Achieving satisfactory results in practical scenarios remains challenging. In response, this study introduces a novel Reverse Path Planning (RPP) methodology tailored for industrial manipulators. The approach commences by conceptualizing… More > Graphic Abstract

Xin Ai^1,2,*, Mian Chen¹

FDMP-Fluid Dynamics & Materials Processing, Vol.20, No.3, pp. 661-670, 2024, DOI:10.32604/fdmp.2023.026819 - 12 January 2024

Abstract

The efficient development and exploitation of shale oil depends on long-distance horizontal wells. As the degree of cleaning of the wellbore plays a key role in these processes, in this study, this problem is investigated experimentally by focusing on the dimensionless cuttings bed height. A method is proposed to calculate the horizontal-well hydraulic extension taking into account the influence of the wellbore cleaning degree on the wellbore pressure distribution and assess the effect of a variety of factors such as the bottom hole pressure, the circulating pressure drop, the drilling pump performance and the formation

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Hong Qian^1,2, Haixin Wang^1,*, Guangji Wang³, Qingyun Yan⁴

CMES-Computer Modeling in Engineering & Sciences, Vol.139, No.1, pp. 679-698, 2024, DOI:10.32604/cmes.2023.043377 - 30 December 2023

Abstract This study presents a proposed method for assessing the condition and predicting the future status of condensers operating in seawater over an extended period. The aim is to address the problems of scaling and corrosion, which lead to increased loss of cold resources. The method involves utilising a set of multivariate feature parameters associated with the condenser as input for evaluation and trend prediction. This methodology offers a precise means of determining the optimal timing for condenser cleaning, with the ultimate goal of improving its overall performance. The proposed approach involves the integration of the… More >

Song Wang^1,*, Fei Xie¹, Fengye Yang¹, Shengxuan Qiu¹, Chuang Liu², Tong Li³

Energy Engineering, Vol.120, No.10, pp. 2273-2285, 2023, DOI:10.32604/ee.2023.030107 - 28 September 2023

Abstract Winding is one of the most important components in power transformers. Ensuring the health state of the winding is of great importance to the stable operation of the power system. To efficiently and accurately diagnose the disc space variation (DSV) fault degree of transformer winding, this paper presents a diagnostic method of winding fault based on the K-Nearest Neighbor (KNN) algorithm and the frequency response analysis (FRA) method. First, a laboratory winding model is used, and DSV faults with four different degrees are achieved by changing disc space of the discs in the winding. Then,… More > Graphic Abstract

Muayad M. Hasan^1,*, Firas K. Al-Zuhairi², Anfal H. Sadeq¹, Rana A. Azeez¹

FDMP-Fluid Dynamics & Materials Processing, Vol.19, No.11, pp. 2827-2835, 2023, DOI:10.32604/fdmp.2023.027746 - 18 September 2023

Abstract Solvents are generally used to reduce the viscosity of heavy crude oil and ultimately enhance oil recovery. Recently, a new method has been introduced where nanoparticles (NPs) are exploited to induce enhanced oil recovery owing to their ability to improve the mobility ratio, dampen the interfacial tension, and alter rock wettability. This study investigated the integration of nano-alumina (Al₂O₃) NPs with an n-hexane solvent. In particular, a Brookfield viscometer has been used to measure the crude oil viscosity and it has been found that NPs can effectively lead to a significant decrease in the overall oil More >

Jian Shang^1,2,*, Runmin Guan², Wei Wang²

Intelligent Automation & Soft Computing, Vol.37, No.3, pp. 2609-2626, 2023, DOI:10.32604/iasc.2023.037694 - 11 September 2023

Abstract The wide application of intelligent terminals in microgrids has fueled the surge of data amount in recent years. In real-world scenarios, microgrids must store large amounts of data efficiently while also being able to withstand malicious cyberattacks. To meet the high hardware resource requirements, address the vulnerability to network attacks and poor reliability in the traditional centralized data storage schemes, this paper proposes a secure storage management method for microgrid data that considers node trust and directed acyclic graph (DAG) consensus mechanism. Firstly, the microgrid data storage model is designed based on the edge computing… More >

Siyu Lu¹, Ligao Cai¹, Zhixin Liu², Shan Liu¹, Bo Yang¹, Lirong Yin³, Mingzhe Liu⁴, Wenfeng Zheng^1,*

Computer Systems Science and Engineering, Vol.47, No.2, pp. 1881-1899, 2023, DOI:10.32604/csse.2023.034853 - 28 July 2023

Abstract With the development of Internet technology, the explosive growth of Internet information presentation has led to difficulty in filtering effective information. Finding a model with high accuracy for text classification has become a critical problem to be solved by text filtering, especially for Chinese texts. This paper selected the manually calibrated Douban movie website comment data for research. First, a text filtering model based on the BP neural network has been built; Second, based on the Term Frequency-Inverse Document Frequency (TF-IDF) vector space model and the doc2vec method, the text word frequency vector and the More >