Haytham Ayoub, Ehab Hussein Bani-Hani^*

Energy Engineering, Vol.117, No.1, pp. 41-47, 2020, DOI:10.32604/EE.2020.010412

Abstract Offshore wind turbine is analyzed theoretically and experimentally for improving wind energy harvesting. The energy produced is calculated at different wind speeds. The wind speed curve is generated by measuring the wind speed on daily base for one year. Curves that show the power extraction for experimental study and from the theoretical calculations are generated. The energy production investigation is expanded over a period of 15 years after comparing the annual energy production in theory and practice. The study shows the cost of electricity over the same time period assuming different interest rates. Three time intervals are shown that are… More >

Ali Safari Variani¹, Ali Dastamoz¹, Sajad Zare², Ahmad Nikpey¹, Saeid Ahmadi^1,*

Sound & Vibration, Vol.54, No.1, pp. 43-55, 2020, DOI:10.32604/sv.2020.08636

Abstract This work investigated multiple jet nozzles with various geometrical shape, number of exits, and material on reducing noise radiated from jet flows. Nozzles are categorized in two groups with few and many exit numbers, each with various exit shapes, slot and circular, and geometry. Firstly, nozzles are designed and then fabricated by a 3D printer, Form Labs, Form2USA, with polymeric resin. Also, the nozzle with the most noise reduction made of stainless steel. Noise and air thrust were measured at three air pressure gauges, 3, 5, 7 BAR and directions from nozzle apex, 30°, 90°, 135°. Nozzles with slot exit… More >

Xiaohong Yin¹, Hengdong Zhang¹, Jiana Chen¹, Ruichun Zhang², Longsheng Liu², Min Huang^1,*, Guanghui Chen¹, Yingbin Zou¹

Phyton-International Journal of Experimental Botany, Vol.89, No.1, pp. 97-102, 2020, DOI:10.32604/phyton.2020.08093

Abstract Eating quality is of paramount importance to rice (Oryza sativa L.) consumers and soft rice with low amylose content has become popular in China. This study was conducted to evaluate the performance of soft rice grown in the early season (ES) dominated by non-soft rice. Field experiments were conducted in Yongan and Santang, Hunan Province, China from 2016-2018. Results showed that grain amylose content in soft rice cultivars was consistently lower in the ES compared to the late season (LS). The lower grain amylose content in the ES compared to the LS was partly attributed to higher average daily mean… More >

Lei Tian, Liuchao Qiu^*, Jingjun Li, Yongsen Yang

Journal of Renewable Materials, Vol.8, No.2, pp. 154-170, 2020, DOI:10.32604/jrm.2020.08701

Abstract In recent decades, the utilization of waste tires, plastic and artificial shale ceramsite as alternative fine aggregate to make self-compacting concrete (SCC) has been recognized as an eco-friendly and sustainable method to manufacture renewable construction materials. In this study, three kinds of recycled aggregates: recycled tire rubber particles, wood-plastic particles, artificial shale ceramsite were used to replace the sand by different volume (5%, 10%, 20% and 30%), and their effects on the fresh and hardened properties of SCC were investigated. The slump flow and V-funnel tests were conducted to evaluate the fresh properties of modified-SCC mixtures. The hardened properties include… More >

Kun Zhu¹, Shi Ying^{1, *}, Nana Zhang¹, Rui Wang¹, Yutong Wu¹, Gongjin Lan², Xu Wang²

CMC-Computers, Materials & Continua, Vol.62, No.3, pp. 1161-1185, 2020, DOI:10.32604/cmc.2020.05247

Abstract SaaS software that provides services through cloud platform has been more widely used nowadays. However, when SaaS software is running, it will suffer from performance fault due to factors such as the software structural design or complex environments. It is a major challenge that how to diagnose software quickly and accurately when the performance fault occurs. For this challenge, we propose a novel performance fault diagnosis method for SaaS software based on GBDT (Gradient Boosting Decision Tree) algorithm. In particular, we leverage the monitoring mean to obtain the performance log and warning log when the SaaS software system runs, and… More >

Yadong Zhang^{1, *}, Jiye Zhang²

FDMP-Fluid Dynamics & Materials Processing, Vol.16, No.1, pp. 105-120, 2020, DOI:10.32604/fdmp.2020.07959

Abstract The object of research of this paper is the DSA380 high-speed pantograph. The near-field unsteady flow around the pantograph was investigated using large eddy simulation (LES) while the far-field aerodynamic noise was analysed in the frame of the Ffowcs Williams-Hawkings (FW-H) acoustic analogy. According to the results, the contact strip, base frame and knuckle are the main aerodynamic noise sources, with vortex shedding, flow separation and recombination around the pantograph being related key physical factors. The aerodynamic noise radiates outwards in the form of spherical waves when the distance of the noise receiving point is farther than 8 m. The… More >

Xiaohan Zhang¹, Yao Jiang², Tian Li^{1, *}

FDMP-Fluid Dynamics & Materials Processing, Vol.16, No.1, pp. 67-76, 2020, DOI:10.32604/fdmp.2020.07776

Abstract The aerodynamic resistance of a train running in the open air limits the maximum speed that can be attained by the train. For this reason, evacuated tube trains (ETT) are being considered as valid alternatives to be implemented in the future. The atmosphere in the tube, the so-called blocking ratio and the length of the streamlined nose are the key factors affecting the aerodynamic performances of these trains. In the present work, we investigate evacuated tube trains with different lengths of the streamline nose on the basis of computational fluid dynamics (CFD). The three-dimensional steady compressible Navier-Stokes equations are solved.… More >

Zhiyuan Dai¹, Tian Li^{1, *}, Weihua Zhang¹, Jiye Zhang¹

FDMP-Fluid Dynamics & Materials Processing, Vol.16, No.1, pp. 31-40, 2020, DOI:10.32604/fdmp.2020.07661

Abstract Pantograph is a critical component of the high-speed train. It collects power through contact with catenary, which significantly affects the running safety of the train. Pantograph with double collector strips is one common type. The aerodynamic performance of the collector strips may affect the current collection of the pantograph. In this study, the aerodynamic performance of the pantograph with double strips is investigated. The numerical results are consistent with the experimental ones. The error in the aerodynamic drag force of the pantograph between numerical and experimental results is less than 5%. Three different conditions of the strips are studied, including… More >

Yundong Han¹, Dawei Chen¹, Shaoqing Liu¹, Gang Xu²

FDMP-Fluid Dynamics & Materials Processing, Vol.16, No.1, pp. 1-19, 2020, DOI:10.32604/fdmp.2020.06525

Abstract A series of tests have been conducted using a Cryogenic Wind Tunnel to study the effect of Reynolds number (Re) on the aerodynamic force and surface pressure experienced by a high speed train. The test Reynolds number has been varied from 1 million to 10 million, which is the highest Reynolds number a wind tunnel has ever achieved for a train test. According to our results, the drag coefficient of the leading car decreases with higher Reynolds number for yaw angles up to 30º. The drag force coefficient drops about 0.06 when Re is raised from 1 million to 10… More >

Jin Wang^{1, 2, 3}, Yu Gao², Chang Zhou², R. Simon Sherratt⁴, Lei Wang^{5, *}

CMC-Computers, Materials & Continua, Vol.62, No.2, pp. 695-711, 2020, DOI:10.32604/cmc.2020.08674

Abstract Wireless Sensor Networks (WSNs) are usually formed with many tiny sensors which are randomly deployed within sensing field for target monitoring. These sensors can transmit their monitored data to the sink in a multi-hop communication manner. However, the ‘hot spots’ problem will be caused since nodes near sink will consume more energy during forwarding. Recently, mobile sink based technology provides an alternative solution for the long-distance communication and sensor nodes only need to use single hop communication to the mobile sink during data transmission. Even though it is difficult to consider many network metrics such as sensor position, residual energy… More >