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Showing records 37693 to 37717 of 43292. [First] Page: 1 1505 1506 1507 1508 1509 1510 1511 1512 1513 Last
Synthesis and Characterization of Nanoformulation of the Broad-Spectrum Enzyme Inhibitor Mancozeb by Polyethylene Glycol Capping and Its Dissipation Kinetics in Water Using TiO2 Nanoparticles
Wafa Mahmoud Daqa, Adil Alshoaibi, Faheem Ahmed, Tentu Nageswara Rao
February 21, 2023 (v1)
Subject: Materials
Keywords: dissipation half-life (DT50), mancozeb nanoformulation, photocatalytic, photolytic, polyethylene glycol, TiO2 nanoparticles
The poly(ethylene) glycol (PEG) capped mancozeb nanoformulation was prepared by the ultrasonic method using a 1% mancozeb solution and 20% capping agent, PEG-4000. The synthesized nanoformulation was characterized using UV-visible, FTIR, SEM and TEM techniques. The photolytic and photo catalytic experiments were carried out in a Borosil glass bottle in the presence of sunlight, varying the pH proportions at a single fortification level (1.0 g/mL) in ground water, under sunlight. The optimal catalyst concentration for complete degradation was observed to be 0.1 percent. The mancozeb nanoformulation in water was determined using the HPLC-PDA method, and the rate constant and the 50% degradation (DT50) values were calculated based on the results. The photolytic results show that there is no significant loss of residues due to adsorption. Titanium dioxide (TiO2) was discovered to be an excellent decontaminating catalyst in a variety of water samples. The compound survives for several days... [more]
Smart Technology Prioritization for Sustainable Manufacturing in Emergency Situation by Integrated Spherical Fuzzy Bounded Rationality Decision-Making Approach
Chia-Nan Wang, Thuy-Duong Thi Pham, Nhat-Luong Nhieu, Ching-Chien Huang
February 21, 2023 (v1)
Keywords: bounded rationality decision-making, multiple criteria decision-making, regret theory, smart technology, spherical fuzzy sets, sustainable manufacturing, the combined compromise solution method, the decision-making trial and evaluation laboratory
The delays and disruptions during the pandemic have awakened interest in the sustainability and resilience of production systems to emergencies. In that context, the deployment of smart technologies has emerged as an almost mandatory development orientation to ensure the stability of manufacturing. The core value of smart technologies is to reduce the dependence on human labor in production systems. Thereby, the negative impacts caused by emergency situations are mitigated. However, the implementation of smart technologies in a specific production system that already exists requires a high degree of suitability. Motivated by this fact, this study proposes an integrated spherical fuzzy bounded rationality decision-making approach, which is composite of the spherical fuzzy decision-making trial and evaluation laboratory (SF DEMATEL) and the spherical fuzzy regret theory-based combined compromise solution (R-SF CoCoSo) method. The proposed approach reflects both the ambiguities and psycho... [more]
Derivation and Verification of Gaussian Terrain Wake Model Based on Wind Field Experiment
Wei Liu, Xiaoxun Zhu, Kaike Wang, Xiaoxia Gao, Shaohai Zhang, Lijiang Dong, Zeqi Shi, Hongkun Lu, Jie Zhou
February 21, 2023 (v1)
Keywords: Coanda effect, Gaussian terrain, lidar, wake model, wind field experiment
Aiming at the problem where the current engineering wake model does not describe the wind speed distribution of the wake in the complex terrain wind farm completely, based on the three-dimensional full wake model (3DJGF wake model), this paper proposed a wake model that can predict the three-dimensional wind speed distribution of the entire wake region in the complex wind farm, taking into account the Coanda effect, wind shear effect, and wake subsidence under the Gaussian terrain. Two types of Doppler lidar were used to conduct wind field experiments, and the inflow wind profile and three-dimensional expansion of the wake downstream of the wind turbine on the Gaussian terrain were measured. The experimental results showed that the wake centerline and terrain curve showed similar variation characteristics, and the near wake profile was similar to a super-Gaussian shape (asymmetric super-Gaussian shape) under low-wind-speed conditions, while the near wake profile presented a bimodal sha... [more]
Numerical Modelling and Validation of Mixed-Mode Fracture Tests to Adhesive Joints Using J-Integral Concepts
Luís F. R. Neves, Raul D. S. G. Campilho, Isidro J. Sánchez-Arce, Kouder Madani, Chander Prakash
February 21, 2023 (v1)
Keywords: adhesive joints, cohesive zone modelling, fracture toughness, mixed-mode, structural adhesive
The interest in the design and numerical modelling of adhesively-bonded components and structures for industrial application is increasing as a research topic. Although research on joint failure under pure mode is widespread, applied bonded joints are often subjected to a mixed mode loading at the crack tip, which is more complex than the pure mode and affects joint strength. Failure of these joints under loading is the objective of predictions through mathematical and numerical models, the latter based on the Finite Element Method (FEM), using Cohesive Zone Modelling (CZM). The Single leg bending (bending) testing is among those employed to study mixed mode loading. This work aims to validate the application of FEM-CZM to SLB joints. Thus, the geometries used for experimental testing were reproduced numerically and experimentally obtained properties were employed in these models. Upon the validation of the numerical technique, a parametric study involving the cohesive laws’ parameters... [more]
Adsorption Characteristics and Mechanism of Methylene Blue in Water by NaOH-Modified Areca Residue Biochar
Yixin Lu, Yujie Liu, Chunlin Li, Haolin Liu, Huan Liu, Yi Tang, Chenghan Tang, Aojie Wang, Chun Wang
February 21, 2023 (v1)
Subject: Materials
Keywords: Adsorption, areca residue, biochar, methylene blue, modification
To solve the water pollution problem caused by methylene blue (MB), areca residue biochar (ARB) was prepared by pyrolysis at 600 °C, and modified areca residue biochar (M-ARB) was obtained by modifying ARB with 1.5 mol/L NaOH, and they were utilized to adsorb and eliminate MB from water. The structural characteristics of ARB and M-ARB were examined, and the main influencing factors and adsorption mechanism of MB adsorption process were investigated. The outcomes demonstrated an increase in M-ARB’s specific surface area and total pore volume of 66.67% and 79.61%, respectively, compared with ARB, and the pore structure was more abundant, and the content of oxygen element was also significantly increased. When the reaction temperature was 25 °C, starting pH of the mixture was 10, the initial MB concentration was 50 mg/L, the ARB and M-ARB dosages were 0.07 g/L and 0.04 g/L, respectively, the adsorption equilibrium was achieved at about 210 min, and the elimination rate for MB exceeded 94%... [more]
Temperature-Related N2O Emission and Emission Potential of Freshwater Sediment
Shuai Li, Ang Yue, Selina Sterup Moore, Fei Ye, Jiapeng Wu, Yiguo Hong, Yu Wang
February 21, 2023 (v1)
Subject: Environment
Keywords: dissolved N2O, freshwater lake, N2O emission, temperature sensitivity
Nitrous oxide (N2O) is a major radiative forcing and stratospheric ozone-depleting gas. Among natural sources, freshwater ecosystems are significant contributors to N2O. Although temperature is a key factor determining the N2O emissions, the respective effects of temperature on emitted and dissolved N2O in the water column of freshwater ecosystems remain unclear. In this study, 48 h incubation experiments were performed at three different temperatures; 15 °C, 25 °C, and 35 °C. For each sample, N2O emission, dissolved N2O in the overlying water and denitrification rates were measured, and N2O-related functional genes were quantified at regular intervals. The highest N2O emission was observed at an incubation of 35 °C, which was 1.5 to 2.1 factors higher than samples incubated at 25 °C and 15 °C. However, the highest level of dissolved N2O and estimated exchange flux of N2O were both observed at 25 °C and were both approximately 2 factors higher than those at 35 °C and 15 °C. The denitri... [more]
Agent-Based and Stochastic Optimization Incorporated with Machine Learning for Simulation of Postcombustion CO2 Capture Process
Huilan Zheng, Gaurav Mirlekar, Lars O. Nord
February 21, 2023 (v1)
Keywords: data-driven process modeling, Machine Learning, postcombustion carbon capture, process optimization
In this paper, a novel method is proposed for the incorporation of data-driven machine learning techniques into process optimization. Such integration improves the computational time required for calculations during optimization and benefits the online application of advanced control algorithms. The proposed method is illustrated via the chemical absorption-based postcombustion CO2 capture process, which plays an important role in the reduction of CO2 emissions to address climate challenges. These processes simulated in a software environment are typically based on first-principle models and calculate physical properties from basic physical quantities such as mass and temperature. Employing first-principle models usually requires a long computation time, making process optimization and control challenging. To overcome this challenge, in this study, machine learning algorithms are used to simulate the postcombustion CO2 capture process. The extreme gradient boosting (XGBoost) and suppor... [more]
Dynamics of Pressure Variation in Closed Vessel Explosions of Diluted Fuel/Oxidant Mixtures
Venera Giurcan, Domnina Razus, Maria Mitu, Codina Movileanu
February 21, 2023 (v1)
Keywords: confined explosions, Ethylene, nitrogen dilution, nitrous oxide, pressure dynamics
Nitrous oxide is widely used as oxidizer or nitriding agent in numerous industrial activities such as production of adipic acid and caprolactam and even for production of some semiconductors. Further, it is used as an additive in order to increase the power output of engines, and as an oxidizer in propulsion systems of rockets, because it has a large heat of formation (+81.6 kJ mol−1). N2O is highly exothermic, and during its decomposition a supplementary heat amount is released, so it needs special handling conditions. The combustion of fuels in nitrous oxide atmosphere can lead to high unstable and turbulent deflagrations that speedily self-accelerate and therefore a deflagration can change to a detonation. The peak explosion pressure and the maximum rate of pressure rise of explosions in confined spaces are key safety parameters to evaluate the hazard of processes running in closed vessels and for design of enclosures able to withstand explosions or of their vents used as relief dev... [more]
Dynamic Performance Assessment of PMSG and DFIG-Based WECS with the Support of Manta Ray Foraging Optimizer Considering MPPT, Pitch Control, and FRT Capability Issues
Mohamed Metwally Mahmoud, Basiony Shehata Atia, Almoataz Y. Abdelaziz, Noura A. Nour Aldin
February 21, 2023 (v1)
Keywords: crowbar system, DFIG, FRT, manta ray foraging optimizer (MRFO), PMSG, wind energy
Wind generators have attracted a lot of attention in the realm of renewable energy systems, but they are vulnerable to harsh environmental conditions and grid faults. The influence of the manta ray foraging optimizer (MRFO) on the dynamic performance of the two commonly used variable speed wind generators (VSWGs), called the permanent magnet synchronous generator (PMSG) and doubly-fed induction generator (DFIG), is investigated in this research article. The PMSG and DFIG were exposed to identical wind speed changes depending on their wind turbine characteristics, as well as a dangerous three-phase fault, to evaluate the durability of MRFO-based wind side controllers. To protect VSWGs from hazardous gusts and obtain the optimum power from incoming wind speeds, we utilized a pitch angle controller and optimal torque controller, respectively, in our study. During faults, the commonly utilized industrial approach (crowbar system) was exclusively employed to aid the studied VSWGs in achievi... [more]
Digital Twin Modelling Method of Five-Axis Machine Tool for Predicting Continuous Trajectory Contour Error
Dun Lyu, Jian Liu, Shiyou Luo, Shuo Liu, Qunlin Cheng, Hui Liu
February 21, 2023 (v1)
Keywords: Continuous Trajectory Contour Error (CTCE), Digital Twin (DT), error prediction, five-axis machine tool
The CNC machine tool is the passive executor of machining code. It cannot predict the machining accuracy during machining. If the error is found to be out of tolerance after processing, it will not only scrap the parts, but also greatly affect the processing efficiency. This phenomenon is very prominent when machining sculptured surface parts with five-axis machine tools. Therefore, this paper proposes a Digital Twin (DT) modeling method of five-axis machine tools for predicting Continuous Trajectory Contour Error (CTCE) caused by tracking errors and geometric errors. The DT consists of three parts: the Setpoints Trajectory (ST) model, the Actual Trajectory (AT) model considering tracking errors and geometric errors and the CTCE model. For a specific machine tool, according to the basic geometric information of the machine tool (tool length, kinematic chain information, etc.) and 41 geometric errors, the DT can be established. Inputting the Setpoints Positions (SPs) and the Linear Enco... [more]
A Resilience-Oriented Bidirectional ANFIS Framework for Networked Microgrid Management
Muhammad Zeshan Afzal, Muhammad Aurangzeb, Sheeraz Iqbal, Atiq ur Rehman, Hossam Kotb, Kareem M. AboRas, Elmazeg Elgamli, Mokhtar Shouran
February 21, 2023 (v1)
Keywords: adaptive neural network, bidirectional ANFIS, Energy Storage, fuzzy, microgrid, resilience
This study implemented a bidirectional artificial neuro-fuzzy inference system (ANFIS) to solve the problem of system resilience in synchronized and islanded grid mode/operation (during normal operation and in the event of a catastrophic disaster, respectively). Included in this setup are photovoltaics, wind turbines, batteries, and smart load management. Solar panels, wind turbines, and battery-charging supercapacitors are just a few of the sustainable energy sources ANFIS coordinates. The first step in the process was the development of a mode-specific control algorithm to address the system’s current behavior. Relative ANFIS will take over to greatly boost resilience during times of crisis, power savings, and routine operations. A bidirectional converter connects the battery in order to keep the DC link stable and allow energy displacement due to changes in generation and consumption. When combined with the ANFIS algorithm, PV can be used to meet precise power needs. This means it c... [more]
Development of Co-Amorphous Loratadine−Citric Acid Orodispersible Drug Formulations
Emőke Margit Rédai, Emese Sipos, Robert Alexandru Vlad, Paula Antonoaea, Nicoleta Todoran, Adriana Ciurba
February 21, 2023 (v1)
Subject: Materials
Keywords: co-amorphous, direct compression, loratadine, lyophilization, orally disintegrating
This study aimed at the preparation and characterization of co-amorphous loratadine−citric acid orally disintegrating dosage forms (ODx). A co-amorphous loratadine−citric acid was prepared by solvent evaporation method in three different molecular ratios. DSC, FTIR, and dissolution studies have been conducted for the binary system. The co-amorphous system was used to obtain oral lyophilizates and orally disintegrating tablets by direct compression. Diameter, thickness, hardness, disintegration time, uniformity of mass, and dissolution was determined for the dosage forms. DSC curves showed a lack of sharp endothermic peaks for the binary systems. FTIR spectra presented a hypsochromic modification of the characteristic peaks. Dissolution studies indicated a five-fold increase in the dissolved amount compared to pure loratadine in water. Disintegration times of direct compression ODx varied in the range of 34−41 s and for freeze-dried ODx in the range of 8−9 s. Friability was under 1% in... [more]
Magnetic Activated Biochar Fe3O4-MOS Made from Moringa Seed Shells for the Adsorption of Methylene Blue
Meiping Li, Cheng Dong, Caixia Guo, Ligang Yu
February 21, 2023 (v1)
Subject: Materials
Keywords: Adsorption, methylene blue (MB), moringa seed shells, ultrasonic-assisted impregnation
In recent years, more and more biochars have been employed to treat dye wastewater. In order to increase the utilization of moringa seed shell resources and enrich the removal method of methylene blue (MB) in solution, in the current study, the magnetic moringa seed shells biochar was prepared through ultrasonic-assisted impregnation and pyrolysis, while Fe3O4 was used to activate the material to obtain adsorption (Fe3O4-MOS). The prepared adsorbents were characterized by SEM-EDS, XRD, XPS, FTIR, N2 adsorption and desorption and VSM. Under the suitable experimental conditions, the removal rate can be close to 100% and the maximum adsorption capacity of MB could be 219.60 mg/g. The Freundlich model provided a good match to the data presented by the adsorption isotherm, and the adsorption of MB on Fe3O4-MOS was a spontaneous and endothermic reaction. Study of the mechanism indicated that pore adsorption, electrostatic interaction, hydrogen bond, and π-π interaction were the major adsorpt... [more]
3D Computational Fluid Dynamics Analysis of a Convective Drying Chamber
Miguel Andrés Mauricio Daza-Gómez, Carlos Andrés Gómez Velasco, Juan Carlos Gómez Daza, Nicolás Ratkovich
February 21, 2023 (v1)
Keywords: Computational Fluid Dynamics, convective drying, drying industry, heat pump dryer
The drying industry has grown considerably due to the tremendous demand for non-perishable food. Convective drying is one of the most popular equipment in the drying industry (food, chemical, pharmaceutical, etc.). One of the drawbacks of this equipment, when used for convective drying, is the non-uniformity in the final product quality. This study presents the development of a numerical model through Computational Fluid Dynamics (CFD). The drying chamber of a heat pump dryer is assessed from the perspective of drying air velocity and temperature profiles. The model was developed by solving different transport phenomena-related equations. The established methodology was set up to evaluate how the drying air velocity and temperature distribution affect the drying chamber. These results will define if there is a need to redesign it. The air velocity and temperature profile results show a need to redesign the chamber. Only trays 2, 3, and 4 are the ones that would achieve the drying of th... [more]
Transcriptome Analysis Reveals the Involvement of Alternative Splicing in the Nitrogen Starvation Response of Chlamydomonas reinhardtii
Xingcai Yang, Xiangyu Li, Jialin Zhao, Mingshi Xie, Xinyi Li, Bin Jia, Ying Huang
February 21, 2023 (v1)
Keywords: abiotic stress, alternative splice, C. reinhardtii, post-transcriptional regulation, spliceosome
Alternative splicing (AS) is a regulatory mechanism of post-transcriptional regulation that plays an important role in plant response to abiotic stresses. However, corresponding research involving the mechanism of AS in the nitrogen starvation response of C. reinhardtii is rare. This study performed a comprehensive and systematic analysis of AS events in C. reinhardtii at nine time points (0 h, 10 m, 30 m, 1 h, 6 h, 8 h, 24 h, and 48 h) under nitrogen starvation. It used STAR and rMATS tools to identify and quantify the probability of the AS event happening through the transcriptome high-throughput sequencing data. A total of 5806 AS events in 3500 genes were identified, and the retained intron and skipped exon were considered the main AS types. The genes related to the AS event in nitrogen starvation were mainly involved in spliceosome and transporter and enriched in the citrate cycle and fatty acid degradation pathways. These results suggested that AS may play an important role in th... [more]
Agglomeration of Spray-Dried Milk Powder in a Spray Fluidized Bed: A Morphological Modeling
Abhinandan Kumar Singh, Evangelos Tsotsas
February 21, 2023 (v1)
Keywords: agglomeration, Modelling, Monte Carlo, morphology, spray fluidized bed
The type of solid substrate plays a critical role in determining the kinetics of the spray fluidized bed (SFB) agglomeration process. In the case of porous (also soft) primary particles (PPs), droplet aging is due to imbibition and drying. The surface properties of the substrate also change due to imbibition. The focus of the present work is to simulate the agglomeration of the spray-dried milk powder using the Monte Carlo (MC) method coupled with a drying-imbibition model. In order to extract the morphology of the formed agglomerates, an aggregation model is employed. Further, this aggregation model is employed to predict the number of positions on the PPs (later agglomerates) for droplet deposition; previously, the ‘concept of positions’ was used. The transient growth of different milk powders (whole and skim) is depicted using the enhanced MC model. The enhancement in the droplet deposition model had a prominent influence on the overall kinetics of agglomeration. As expected, this e... [more]
The Comparison Analysis of Uniform-and Variable-Rate Fertilizations on Winter Wheat Yield Parameters Using Site-Specific Seeding
Marius Kazlauskas, Egidijus Šarauskis, Kristina Lekavičienė, Vilma Naujokienė, Kęstutis Romaneckas, Indrė Bručienė, Sidona Buragienė, Dainius Steponavičius
February 21, 2023 (v1)
Keywords: fertilizer, maps, precision agriculture, seed, soil, variable-rate fertilization
Wheat is among the world’s most important agricultural crops, with winter wheat accounting for approximately 25.5% of the total agricultural crop in Lithuania. The unchangeable goal of crop production is to achieve good and economically beneficial crop yield, but such efforts are often based on conventional agrotechnological solutions, and excessive fertilization, which is uneconomical and negatively affects the soil, the environment, and human health. In order to produce a rich and high-quality cereal crop, scientists and farmers are increasingly focusing on managing the sowing and fertilization processes. Precision technologies based on spectrometric methods of soil and plant characterization can be used to influence the optimization of sowing and fertilizer application rates without compromising crop yield and quality. The aim of this study was to investigate the effect of site-specific seeding and variable-rate precision fertilization technologies on the growth, yield, and quality... [more]
The Influence of Cryogrinding on Essential Oil, Phenolic Compounds and Pigments Extraction from Myrtle (Myrtus communis L.) Leaves
Daniela Cvitković, Patricija Lisica, Zoran Zorić, Sandra Pedisić, Maja Repajić, Verica Dragović-Uzelac, Sandra Balbino
February 21, 2023 (v1)
Subject: Biosystems
Keywords: cryogrinding, essential oil, myrtle, phenols, pigments
The aim of this study was to investigate the influence of cryogrinding pretreatment on the recovery of essential oil, phenolics and pigments from myrtle leaves. The duration of cryogrinding (3, 6 and 9 min) in combination with the duration of hydrodistillation (30, 60 and 90 min) for the isolation of essential oils and the duration of hydroethanolic extraction (5, 10 and 15 min) for the isolation of phenols and pigments were studied as independent factors in a full factorial design. The major volatile components detected in myrtle leaf essential oil were myrtenyl acetate, 1,8-cineole, α-pinene and linalool. The most abundant phenols detected were myricetin derivatives (myricetin 3-O-galactoside and myricetin 3-O-rhamnoside), galloylquinic acid, myricetin and digalloylquinic acid, while the major pigments were chlorophyll b, pheophytin a and lutein. A 3 min cryogrinding pretreatment significantly increased the yield and concentrations of essential oil volatile compounds and reduced the... [more]
Life Cycle Energy Consumption and GHG Emissions of the Copper Production in China and the Influence of Main Factors on the above Performance
Lingchen Liu, Dong Xiang, Huiju Cao, Peng Li
February 21, 2023 (v1)
Subject: Environment
Keywords: energy consumption, GHG emissions, life cycle assessment, refined copper, time-series
The copper demand and production in China are the largest in the world. In order to obtain the trends of the energy consumption and GHG emissions of copper production in China over a number of years, this paper uses a life cycle analysis method to calculate the above two indexes, in the years between 2004 and 2017. The life cycle energy consumption ranged between 101.78 and 31.72 GJ/t copper and the GHG emissions varied between 9.96 and 3.09 t CO2 eq/t copper due to the improvements in mining and smelting technologies. This study also analyses the influence of electricity sources, auxiliary materials consumption, and copper ore grade on the life cycle performance. Using wind or nuclear electricity instead of mixed electricity can reduce energy consumption by 63.67−76.27% or 64.23−76.94%, and GHG emissions by 64.42−77.84% or 65.08−78.63%, respectively. The GHG emissions and energy consumption of underground mining are approximately 2.97−7.03 times that of strip mining, while the influen... [more]
Research on Driving Factors of Collaborative Integration Implementation of Lean-Green Manufacturing System with Industry 4.0 Based on Fuzzy AHP-DEMATEL-ISM: From the Perspective of Enterprise Stakeholders
Xiaoyong Zhu, Yongmao Xiao, Gongwei Xiao, Xiaojuan Deng
February 21, 2023 (v1)
Keywords: driving factors, enterprise stakeholders, fuzzy AHP-DEMATEL-ISM, Industry 4.0, lean-green manufacturing
The existing research and practices have shown that the coordinated implementation of lean-green manufacturing can have a positive impact on the economic and environmental benefits, which is an effective means to ensure the environmental protection of the production process of manufacturing without damaging their profitability. Within the field of lean-green research, there is still a lack of research to analyze the driving factors for the collaborative implementation of integrated lean and green integration. Although, some scholars and researchers have studied lean and green integration paradigms, their research has mostly focused on lean-green integration practices and their impact on environmental performance and their respective operations. In the context of Industry 4.0, this article investigates the driving forces behind the collaborative integration implementation of a lean-green manufacturing system from the viewpoint of stakeholders. Specifically addressing the issues of corre... [more]
Optimal DGs Siting and Sizing Considering Hybrid Static and Dynamic Loads, and Overloading Conditions
Mariam A. Sameh, Abdulsalam A. Aloukili, Metwally A. El-Sharkawy, Mahmoud A. Attia, Ahmed O. Badr
February 21, 2023 (v1)
Subject: Optimization
Keywords: DGs, dynamic loads, HSA optimization, hybrid loads, static loads
There is no doubt that Distributed Generation (DG) has proved to be an effective solution for satisfying the growing demand within a fleeting period and improving system performance, voltage profile, and power quality, especially on the end user’s side. Thus, in modern distribution systems, DG is preferable to be installed in the vicinity of the end user to enhance the system performance, reduce power losses, and improve grid voltage. In this paper, hybrid static and dynamic load types (100% static, 50% static and 50% dynamic, and 100% dynamic loads) at different overloading conditions, for the standard IEEE 33-bus system, are considered, and power system performance is recorded. Moreover, to improve the power system performance, Distributed Generations (DGs) are optimally sized and allocated in the IEEE 33-bus system using the Harmony Search Algorithm (HSA), and two analytical approaches, respectively, and compared to other reported optimization methods. The results show that, at 100%... [more]
Differences in Physiological Metabolism and Antioxidant System of Different Ecotypes of Miscanthus floridulus under Cu Stress
Jianqiao Qin, Zhiqiang Yan, Xueding Jiang, Huarong Zhao, Shasha Liu, Min Dai, Dexin Xiong, Xi Chen
February 21, 2023 (v1)
Keywords: antioxidant system, copper, Miscanthus floridulus, non-enzymatic substance
To reveal the similarities and differences in the resistance mechanisms of different ecotypes to Cu stress, a pot experiment was used to systematically compare the physiological responses of non-mining ecotype Miscanthus floridulus (collected from Boluo County, Huizhou City) and mining ecotype Miscanthus floridulus (collected from Dabaoshan mining area) under different Cu concentrations. The results showed that chlorophyll a, chlorophyll b and total chlorophyll in the leaves of the two ecotypes of M. floridulus were negatively correlated with Cu stress concentration (p < 0.01), but the extent of decrease for the ecotypes in the mining area was lower than that for the ecotypes in the non-mining area. The values of chlorophyll a/b for both ecotypes increased with increasing Cu treatment concentration, indicating that Cu is more harmful to chlorophyll b than to chlorophyll a for M. floridulus. Cu stress can lead to the accumulation of malondialdehyde (MDA) in the leaves of M. floridulu... [more]
High Efficiency and High Voltage Conversion Ratio Bidirectional Isolated DC−DC Converter for Energy Storage Systems
Yu-En Wu, Kuan-Chi Chen
February 21, 2023 (v1)
Keywords: bidirectional DC–DC converter, three-winding coupled inductor, zero-voltage switching (ZVS)
In this paper, a novel high-efficiency bidirectional isolated DC−DC converter that can be applied to an energy storage system for battery charging and discharging is proposed. By integrating a coupled inductor and switched-capacitor voltage doubler, the proposed converter can achieve isolation and bidirectional power flow. The proposed topology comprises five switches and a common core coupled inductor that uses only a set of complementary pulse-width-modulated signals to control and achieve high voltage gain without requiring high turn ratios or excessive duty cycles. Moreover, the proposed topology can recover the leakage inductance energy to improve the conversion efficiency. The main switches exhibit zero-voltage switching, which reduces the switching losses. A 500-W bidirectional converter is used to verify the feasibility of the proposed bidirectional converter through theoretical analysis and experiments. The experimental results indicate that the highest efficiency of the propo... [more]
Deep Learning Based Target Tracking Algorithm Model for Athlete Training Trajectory
Yue Wang
February 21, 2023 (v1)
Keywords: attention mechanism, deep learning, search strategy, SiamRPN, targettracking algorithm
The main function of the athlete tracking system is to collect the real-time competition data of the athletes. Deep learning is a research hotspot in the field of image and video. With the rapid development of science and technology, it has not only made a breakthrough in theory, but also achieved excellent results in practical application. SiamRPN (Siamese Region Proposal Network) is a single target tracking network model based on deep learning, which has high accuracy and fast operation speed. However, in long-term tracking, if the target is completely obscured and out of the sight of SiamRPN, the tracking of the network will be invalid. Considering the difficulty of long-term tracking, the algorithm is improved and tested by introducing channel attention mechanism and local global search strategy into SiamRPN. Experimental results show that this algorithm has higher accuracy and prediction average overlap rate than the original SiamRPN algorithm when performing tracking tasks on lon... [more]
A Data-Driven Fine-Management and Control Method of Gas-Extraction Boreholes
Xiaoyang Cheng, Haitao Sun
February 21, 2023 (v1)
Keywords: borehole design, borehole repair, gas extraction, refined management
In order to improve the efficiency of gas extraction in coal mines, a data-driven fine-management and control method for gas extraction is proposed. Firstly, the accurate prediction of coal seam thickness and gas content was used to evaluate the gas reserves. Based on the time relationship between mining activities and gas extraction, the calculation model of borehole distance in different extraction units is established, and the differential borehole design is realized. Then, a drilling video-surveillance system and drilling trajectory measurement device are used to control the drilling process and the construction effect. Finally, the model of extraction data-correction and the identification of failed boreholes is established, then the failed boreholes are repaired. The technology method provided in the paper has realized the fine control of gas-extraction borehole design, construction, measurement, and repair, and formed a more scientific gas-extraction borehole control technology... [more]
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