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Records Added in February 2023
Records added in February 2023
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Showing records 12401 to 12425 of 12650. [First] Page: 493 494 495 496 497 498 499 500 501 Last
Deep Learning-Based Human Body Posture Recognition and Tracking for Unmanned Aerial Vehicles
Min-Fan Ricky Lee, Yen-Chun Chen, Cheng-Yo Tsai
February 21, 2023 (v1)
Keywords: activity recognition, deep learning, pose estimation, unmanned aerial vehicles
For many applications (e.g., surveillance and disaster response), situational awareness is essential. In these applications, human body posture recognition in real time plays a crucial role for corresponding response. Traditional posture recognition suffers from accuracy, due to the low robustness against uncertainty. Those uncertainties include variation from the environment (e.g., viewpoint, illumination and occlusion) and the postures (e.g., ambiguous posture and the overlap of multiple people). This paper proposed a drone surveillance system to distinguish human behaviors among violent, normal and help needed based on deep learning approach under the influence of those uncertainties. First, the real-time pose estimation is performed by the OpenPose network, and then the DeepSort algorithm is applied for tracking multi-person. The deep neural network model (YOLO) is trained to recognize each person’s postures based on a single frame of joints obtained from OpenPose. Finally, the fuz... [more]
An Improved Arc Flow Model with Enhanced Bounds for Minimizing the Makespan in Identical Parallel Machine Scheduling
Anis Gharbi, Khaled Bamatraf
February 21, 2023 (v1)
Keywords: identical parallel machines, improved arc flow, integer programming, Scheduling, variable neighborhood search
In this paper, an identical parallel machine problem was considered with the objective of minimizing the makespan. This problem is NP-hard in the strong sense. A mathematical formulation based on an improved arc flow model with enhanced bounds was proposed. A variable neighborhood search algorithm was proposed to obtain an upper bound. Three lower bounds from the literature were utilized in the improved arc flow model to improve the efficiency of the mathematical formulation. In addition, a graph compression technique was proposed to reduce the size of the graph. As a consequence, the improved arc flow model was compared with an arc flow model from the literature. The computational results on benchmark instances showed that the improved arc flow model outperformed the literature arc flow model at finding optimal solutions for 99.97% of the benchmark instances, with the overall percentage of the reduction in time reaching 87%.
Observer-Based Predefined-Time Attitude Control for Spacecraft Subject to Loss of Actuator Effectiveness
Teng Cao, Huajun Gong, Bing Han
February 21, 2023 (v1)
Keywords: attitude control, fault-tolerant control, learning observer, predefined-time stability, spacecraft
The predefined-time tracking problem of spacecraft attitude systems with loss of actuator effectiveness and lumped disturbance including the external disturbance and system uncertainty is studied. In order to obtain the estimation of the actuator efficiency factor more quickly and accurately, a robust learning observer is designed. Based on the fault reconstruction information of the learning observer and the predefined-time stability lemma, a predefined-time tracking fault-tolerant control scheme is proposed for the faulty spacecraft attitude system. The stability of the learning observer and the whole control system is verified by the Lyapunov stability theory. Finally, the effectiveness and advantages of the proposed scheme are illustrated by simulation results including comparisons with existing works.
A New Theobromine-Based EGFRWT and EGFRT790M Inhibitor and Apoptosis Inducer: Design, Semi-Synthesis, Docking, DFT, MD Simulations, and In Vitro Studies
Eslam B. Elkaeed, Reda G. Yousef, Hazem Elkady, Aisha A. Alsfouk, Dalal Z. Husein, Ibrahim M. Ibrahim, Mohamed Alswah, Heba S. A. Elzahabi, Ahmed M. Metwaly, Ibrahim H. Eissa
February 21, 2023 (v1)
Keywords: anti-proliferative, docking, EGFR inhibitors, MD simulation, theobromine
The essential pharmacophoric structural properties were applied to design a new derivative of theobromine as an antiangiogenic EGFR inhibitor. The designed candidate is a (para-nitrophenyl)acetamide derivative of the natural alkaloid, theobromine (T-2-PNPA). The potentialities of T-2-PNPA to inhibit the EGFR protein were studied computationally in an extensive way. Firstly, the molecular docking against EGFRWT and EGFRT790M demonstrated T-2-PNPA’s capabilities of binding with the targeted receptors. Then, the MD experiments (for 100 ns) illustrated through six different studies the changes that occurred in the energy as well as in the structure of EGFR−T-2-PNPA complex. Additionally, an MM-GBSA analysis determined the exact energy of binding and the essential residues. Furthermore, DFT calculations investigated the stability, reactivity, and electrostatic potential of T-2-PNPA. Finally, ADMET and toxicity studies confirmed both the safety as well as the general likeness of T-2-PNPA. Co... [more]
Machine Learning-Based Approach for Modeling the Nanofluid Flow in a Solar Thermal Panel in the Presence of Phase Change Materials
Saeed Alqaed, Jawed Mustafa, Fahad Awjah Almehmadi, Mathkar A. Alharthi, Mohsen Sharifpur, Goshtasp Cheraghian
February 21, 2023 (v1)
Subject: Materials
Keywords: collector, eco-friendly nanoparticles, Machine Learning, PCM, solar energy
Considering the importance of environmental protection and renewable energy resources, particularly solar energy, the present study investigates the temperature control of a solar panel using a nanofluid (NFD) flow with eco-friendly nanoparticles (NPs) and a phase change material (PCM). The PCM was used under the solar panel, and the NFD flowed through pipes within the PCM. A number of straight fins (three fins) were exploited on the pipes, and the output flow temperature, heat transfer (HTR) coefficient, and melted PCM volume fraction were measured for different pipe diameters (D_Pipe) from 4 mm to 8 mm at various time points (from 0 to 100 min). Additionally, with the use of artificial intelligence and machine learning, the best conditions for obtaining the lowest panel temperature and the highest output NFD temperature at the lowest pressure drop have been determined. While the porosity approach was used to model the PCM melt front, a two-phase mixture was used to simulate NFD flow.... [more]
Development of Cement-Based Grouting Material for Reinforcing Narrow Coal Pillars and Engineering Applications
Shunjie Huang, Guangming Zhao, Xiangrui Meng, Xiang Cheng, Qingheng Gu, Gang Liu, Shikui Zhu
February 21, 2023 (v1)
Subject: Materials
Keywords: expansion, grouting material, orthogonal test, roadway support, setting time
The problem needs to be solved about stability control of small coal pillars along goaf in the coal mining process. In this paper, the effects of water reducer, accelerator and expansion agent on the fluidity, setting time, expansion ratio and stone body strength of grouting materials were analyzed through orthogonal experiments, and the optimal ratio of grouting materials was obtained, and it is applied to the engineering site to obtain the reinforcement effect of the coal pillar grouting material on the coal pillar. The results of the study show that: When the dosage of the accelerating agent is 4%, the amount of water-reducer is 0.3%, and the amount of the expansive agent is 6%, the comprehensive performance of the grouting material is the best. After using the new coal pillar grouting material to strengthen the coal pillars, 30 days of monitoring were conducted to determine the deformation of the surrounding rock of the roadway. The shallow separation layer of the surrounding rock... [more]
Challenges and Construction Applications of Solid Waste Management in Middle East Arab Countries
Osama Ibrahim, Ghassan Al-Kindi, Mohsin Usman Qureshi, Salma Al Maghawry
February 21, 2023 (v1)
Subject: Environment
Keywords: Arab countries, construction applications, construction solid waste, health hazards, MENA, municipal solid waste management, Renewable and Sustainable Energy
Over the past few decades, solid waste production, specifically construction waste, in Middle Eastern Arab countries has dramatically increased. This is characterized by several factors, including rapid urbanization, common food wasting habits, diverse culture, lack of proper planning of solid waste processes, insufficient equipment, as well as lack of proper funding. The exponential growth in solid waste generation rates has led to hazards to health and the environment, causing issues related to air and water pollution under the already increasing pressure of climate change. In this review, we analyze the current solid waste challenges in 13 Arab countries, common diseases, and actual projects applied. The selection of Arab countries was mainly based on the countries with the highest population as well as the availability of data in the field of study. This review also highlights the efforts of the Arab governments that implemented several pilot projects that are not sustainable or ef... [more]
Bioactive Compounds from Elderberry: Extraction, Health Benefits, and Food Applications
Oana-Elena Pascariu, Florentina Israel-Roming
February 21, 2023 (v1)
Keywords: anthocyanins, antioxidants, bioactive compounds, polyphenols, Sambucus nigra
Elderberries are appreciated for their antioxidant properties. Sambucus nigra L. is an extremely abundant plant in the wild flora of Romania, but it is underutilized. Elderberry is used in modern and traditional medicine due to the complex chemical composition of the fruit. The content of phenolic compounds is high (516−8974 mg/100 g DW), of which the most abundant are anthocyanins. Phenolic compounds are known for their beneficial effects on the body. Numerous studies have demonstrated the antioxidant capacity, antibacterial, antiviral, antidiabetic, and anticancer properties of the fruit. It is considered that most of the therapeutic properties of elderberries can be correlated with the antioxidant activity they have. S. nigra fruits are also used in the food industry. Some studies have shown that the therapeutic properties of elderberries can also be found in the products obtained from them. Therefore, this review aimed to describe the chemical composition of elderberries and produc... [more]
Real-Time Temperature and Humidity Measurements during the Short-Range Distribution of Perishable Food Products as a Tool for Supply-Chain Energy Improvements
Martim L. Aguiar, Pedro D. Gaspar, Pedro D. Silva, Luísa C. Domingues, David M. Silva
February 21, 2023 (v1)
Keywords: food preservation, food quality, food waste, humidity, intelligent packaging, Supply Chain, temperature, transportation
Food waste results in an increased need for production to compensate for losses. Increased production is directly related to an increase in the environmental impact of agriculture and in the energy needs associated with it. To reduce food waste, the supply chain should maintain ideal preservation conditions. In horticultural products, temperature, and relative humidity are two of the main parameters to be controlled. Monitoring these parameters can help decision-making in logistics and routes management, as well as to diagnose and timely prevent food losses. In the present work, eighteen wireless traceability devices with temperature and relative humidity sensors monitored crates with horticultural products along a short-range distribution route with five stops (4 h 30 m). Sensor data and a location tag were sent via GSM for real-time monitoring. The results showed fluctuations in temperature and relative humidity that reached up to 7.4 °C and 35.3%, respectively. These fluctuations ha... [more]
Targeted Metabolic Analysis and MFA of Insect Cells Expressing Influenza HA-VLP
Alexandre B. Murad, Marcos Q. Sousa, Ricardo Correia, Inês A. Isidro, Manuel J. T. Carrondo, António Roldão
February 21, 2023 (v1)
Keywords: baculovirus, influenza, insect cells, metabolic flux analysis, VLPs
Virus-like particles (VLPs) are versatile vaccine carriers for conferring broad protection against influenza by enabling high-level display of multiple hemagglutinin (HA) strains within the same particle construct. The insect cell-baculovirus expression vector system (IC-BEVS) is amongst the most suitable platforms for VLP expression; however, productivities vary greatly with particle complexity (i.e., valency) and the HA strain(s) to be expressed. Understanding the metabolic signatures of insect cells producing different HA-VLPs could help dissect the factors contributing to such fluctuations. In this study, the metabolic traces of insect cells during production of HA-VLPs with different valences and comprising HA strains from different groups/subtypes were assessed using targeted metabolic analysis and metabolic flux analysis. A total of 27 different HA-VLP variants were initially expressed, with titers varying from 32 to 512 HA titer/mL. Metabolic analysis of cells during the produc... [more]
Research on the Siting Model of Emergency Centers in a Chemical Industry Park to Prevent the Domino Effect
Kerang Cao, Linqi Liang, Yaru Liu, Liwei Wang, Kwang-Nam Choi, Jingyu Gao
February 21, 2023 (v1)
Subject: Optimization
Keywords: chemical industry park, emergency siting, multi-objective optimization, NSGA-II
A chemical industry park (CIP) has a wide variety of hazardous chemicals, and once an accident occurs, the level of danger increases geometrically, while the domino effect may bring devastating consequences. To improve the emergency rescue capability of a chemical park and prevent the domino effect, a certain number of emergency centers are built at sites near the park for the purpose of rapid emergency rescue and deployment of emergency supplies. Based on this, in our study, a siting model of the emergency center of the chemical park, which aims to prevent the domino effect, was constructed by considering the timeliness and safety, while adopting the prevention of the domino effect as a constraint. The NSGA-II algorithm is used to solve the siting model, and the CPLEX method is used for the comparison. This study combines the prevention of the domino effect with multi-objective optimization theory, which has a good and simple applicability for solving the considered problem and can ob... [more]
Providing Antimicrobial Properties to Cardboard Food Packaging by Coating with ZnO, TiO2, and SiO2—Water-Based Varnish Nanocomposites
Tomislav Hudika, Nevijo Zdolec, Marta Kiš, Tomislav Cigula
February 21, 2023 (v1)
Keywords: antimicrobial activity, cardboard packaging, nanocomposite coatings, surface free energy
Packaging acts like a bond between visual communication and production technology. Packaging material is often coated to enhance visual appearance and some protective features. The COVID pandemic changed consumers’ behavior and understanding of the importance regarding the antimicrobial properties of goods that come in contact with hands. The aim of this research is to investigate and determine the antimicrobial properties of nanocomposite coatings which include nanosized zinc oxide (ZnO), titanium dioxide (TiO2), and silicon dioxide (SiO2). For the purpose of this research, a lithographic printed packaging was coated with a nanocomposite composed of flexographic water-based varnish with incorporated ZnO, TiO2, and SiO2 nanosized particles. A total of eight modulations were presented and compared to the lone water-based varnish. The results have shown that applying nanocomposites will increase the total surface free energy of the packaging surface but will decrease the polar component... [more]
An Analysis of Energy and Internal Flow Characteristics of Open Inlet Channel Axial Flow Pumping Devices
Chuanliu Xie, Cheng Zhang, Tenglong Fu, Andong Feng, Tao Zhang, Fan Yang
February 21, 2023 (v1)
Keywords: axial flow pump device, energy characteristics, internal flow characteristics, numerical calculation, open inlet channel
For the purpose of studying the dynamic and inner flow features of an open inlet channel axial flow pump unit, in the present study, numerical calculations using the SST k-ω turbulence model are applied to an open inlet channel axial flow pumping unit based on the NS equation, and experimental validation is then performed. The experimental output indicates that the designed working conditions are Q = 350 L/s, head H = 5.065 m, efficiency η = 79.56%, and the maximum operating head is H = 9.027 m, which is about 1.78 times that of the design head; further, the pump device can operate in a wide range of working conditions. In addition, the design working conditions are within the range of high-efficiency operating conditions. The calculated values and the experimental comparison are all within a 5.0% margin of error; further, the numerical calculations are reliable. The hydraulic loss of the inlet channel under the design condition Q = 350 L/s is 0.0676 m, which satisfies the relationship... [more]
Magnetic Iron Nanoparticles: Synthesis, Surface Enhancements, and Biological Challenges
Jesús Roberto Vargas-Ortiz, Carmen Gonzalez, Karen Esquivel
February 21, 2023 (v1)
Subject: Materials
Keywords: iron oxide, magnetic nanoparticles, nanomaterials, nanoparticles, nanotoxicology
This review focuses on the role of magnetic nanoparticles (MNPs), their physicochemical properties, their potential applications, and their association with the consequent toxicological effects in complex biologic systems. These MNPs have generated an accelerated development and research movement in the last two decades. They are solving a large portion of problems in several industries, including cosmetics, pharmaceuticals, diagnostics, water remediation, photoelectronics, and information storage, to name a few. As a result, more MNPs are put into contact with biological organisms, including humans, via interacting with their cellular structures. This situation will require a deeper understanding of these particles’ full impact in interacting with complex biological systems, and even though extensive studies have been carried out on different biological systems discussing toxicology aspects of MNP systems used in biomedical applications, they give mixed and inconclusive results. Chemi... [more]
Optimization Design of an Alfalfa Seed Airflow Collection and Drainage System Based on Numerical Simulation
Wenpeng Ma, Shining Zhang, Chengqian Jin, Xiang Yin, Guohai Zhang, Lu Zhu
February 21, 2023 (v1)
Keywords: ADAMS, EDEM, Fluent, pneumatic, seeding device
In order to improve the working performance of an Alfalfa air conveyor, a type of horizontal screw conveyor with a seed stirring function was designed. The working process of the horizontal screw conveyor was co-simulated by EDEM software and ADAMS software. The effects of a seed stirring mechanism on population movement characteristics, population stress, the seed mass flow rate and the variation coefficient of each index were obtained. The results showed that the stirring mechanism can effectively improve the mobility of the population, reduce the local dead zone of the population, and increase the material filling coefficient between the spiral blades. Under the same working conditions, the horizontal screw conveyor with a stirring mechanism has a higher conveying efficiency and better conveying uniformity. In order to optimize the structure parameters of the Venturi injector diffuser and improve seeding efficiency and uniformity, EDEM software and Fluent software were used to co-si... [more]
Effects of Low Pressure Injection on Fuel Atomization and Mixture Formation for Heavy Fuel Engines
Rui Liu, Kaisheng Huang, Yuan Qiao, Haocheng Ji, Lingfeng Zhong, Hao Wu
February 21, 2023 (v1)
Keywords: air-assisted atomization, fuel–air mixture, HFE, injection control, two-stroke
The application of direct injection (DI) technology can effectively improve the atomization effect of heavy fuel to reduce the fuel loss of heavy fuel engines (HFE). The fuel spray characteristics directly affect the combustion performance of the engine. To investigate the atomization process and evaporation characteristics of heavy fuel in-cylinder for an air-assisted direct injection (AADI) engine, a simulation calculation model of AADI HFE was established with the use of a computational fluid dynamics tool. The air-assisted injector model and the one-dimensional performance calculation model were verified by test data. The influences of injection timing and injection pressure on the spray characteristics and mixture formation in the engine cylinder were discussed. The results show that the mixture concentration distribution is uniform after the injection timing is advanced, and the mass fraction of the fuel evaporation increases. The earlier injection timing can provide the fuel wit... [more]
Simulation Analysis of Implementation Effects of Construction Waste Reduction Policies
Qiufei Wang, Siyu Li, Ye Yang
February 21, 2023 (v1)
Keywords: construction waste decreasing, evolutionary game, fine, numerical simulation, sewage discharge fees
The development of the construction industry generates construction waste which could contribute to environmental issues. Construction waste reduction management plays an important role in directly reducing emissions and solving the environmental pollution caused by construction waste. The limited rationality hypothesis and an evolutionary game model are used to construct a simulation model for the effects of environmental policies’ influences on the behavior of government and construction enterprises in construction waste reduction activities. Simulation results show that: (1) The government and enterprises evolve in the same direction under the sewage fees system or the subsidy system. The relationship between the initial ratio of the two sides and the position of the saddle point determines the evolution direction of the system. (2) The government could adjust the sewage fees rate, the penalty ratio, and the upper limit of construction waste emission to obtain a superior effect unde... [more]
Calibration and Experimental Studies on the Mixing Parameters of Red Clover Seeds and Coated Powders
Xuejie Ma, Min Liu, Zhanfeng Hou, Junru Li, Xiangyu Gao, Yang Bai, Mengjun Guo
February 21, 2023 (v1)
Keywords: Computational Fluid Dynamics, discrete element method, EDEM, parameter calibration
The physical and mechanical properties of the materials in the swirling fluidized-bed seed pelleting unit affect the mixing degree of the materials in the pelleting and coating process, which is of great significance to research on pelleting and coating. The problem of discrete particle model parameters affecting CFD-DEM simulation results is addressed. In this paper, red clover seeds (referred to as seeds) and pelletized coating powder (referred to as powder) were used as the research objects, and the JKR. model was selected to calibrate the contact parameters between seeds and powder based on particle amplification theory. With the powder rest angle as the response value, a simulation calibration test was conducted; the parameters with significant effects on the response value were screened based on the Plackett−Burman test, and the steepest climb test determined the range of factor levels of essential parameters. The Box−Behnken test was used to establish the curvilinear response su... [more]
Examination of the Effect of Triangular Plate on the Performances of Reverse Rotating Dual Savonius Wind Turbines
Burcin Deda Altan, Afsin Gungor
February 21, 2023 (v1)
Keywords: dual, performance, Renewable and Sustainable Energy, Savonius turbine, Wind
In the present study, the performance of the Savonius wind turbine in designs with dual turbines rotating opposite to each other was examined. To improve the performance of the Savonius wind turbine in the dual turbine design, a triangular plate was placed in front of the turbines. The effects of the geometric parameters of this triangular plate which was placed on the turbine performance were studied. The numerical analyses performed were confirmed by the experimental data of a previous study in the literature. The performance values of Savonius wind turbines were analyzed by numerical analysis, the accuracy of which was proven by experimental data. ANSYS Fluent, a computational fluid dynamics (CFD) program, was used for the performance analysis. In the first stage, the maximum power coefficient (Cp) of the conventional Savonius wind turbine was obtained around 0.17. With the optimum geometric parameter studies, the maximum power coefficient of the Savonius wind turbine in the triangu... [more]
Nanofiltration Treatment of Industrial Wastewater Doped with Organic Dye: A Study of Hydrodynamics and Specific Energy
Rokia Youcef, Nassila Sabba, Amel Benhadji, Hayet Djelal, Nadim Fakhfakh, Mourad Taleb Ahmed
February 21, 2023 (v1)
Keywords: Brilliant Blue FCF, dilution ratio, nanofiltration membrane processes, specific energy consumption, wastewater treatment
This study was conducted to eliminate the ions and molecules present in the industrial wastewater received by the municipal wastewater treatment plant (WWTP) of Reghaia, which is located east of Algiers, Algeria. The process was developed for two different study matrices: (a) the wastewater from WWTP and (b) wastewater mixed with Brilliant Blue FCF (BBF) dye to show the influence of the strength of the ionic solution on the treatment. The most effective operating parameters were determined by assessing the residence time distribution applied to the reactor flow regime. Energy analysis showed the viability of a nanofiltration membrane, improving the permeate flux. The nanofiltration process consumed 1.94 kWh/m3 to reduce the chemical oxygen demand (COD) of 63.58% and 48.35% for raw wastewater and doped BBF wastewater, respectively. The results demonstrated that nanofiltration performance with a volume dilution ratio of 1/2 showed the reduction of the COD of 87.2% after 15 min for undope... [more]
Determination of Viscosity, Density and Interfacial Tension of the Carbon Dioxide−Isopropanol, Argon−Isopropanol, Sulphur Hexafluoride−Isopropanol Binary Systems at 313.15 K and 333.15 K and at Elevated Pressures
Dragana Borjan, Maja Gračnar, Željko Knez, Maša Knez Marevci
February 21, 2023 (v1)
Keywords: argon, Carbon Dioxide, density, interfacial tension, isopropanol, sulphur hexafluoride, viscosity
Viscosity, density, and interfacial tension of three binary systems (carbon dioxide−isopropanol, argon−isopropanol, and sulphur hexafluoride−isopropanol) were measured at temperatures of 313.15 K and 333.15 K and at pressures up to 100 bar for carbon dioxide, and for argon and sulphur hexafluoride up to 500 bar. A vibrating tube densimeter method has been used for density measurements and a variable-volume high-pressure optical view cell with some modifications for the other measurements. The results showed that pressure does not have a high impact on viscosity. Density is found to be a linear function of pressure and temperature and the densities of the investigated binary systems increase with pressure and decrease with temperature. Interfacial tension decreased with the elevated pressure at a constant temperature for all the investigated systems. Accurate prediction of thermodynamic and mass transfer data is fundamental in various engineering and industrial operations to design proc... [more]
The Planning Method of the Multi-Energy Cloud Management Platform with Key Technologies and P2P Trade of Prosumers
Junfang Li, Yue Xing, Xuejin Huang, Donghui Zhang
February 21, 2023 (v1)
Keywords: cloud platform, common information model (CIM), energy management system (EMS), multi-energy system, peer-to-peer (P2P)
To build a multi-energy cloud platform with the distributed generation, energy storage, micro-grid, flexible load, electric vehicle piles for high efficiency application is of great significance. In order to manage the resources for dispatching and trading in the cloud platform, this paper solves three problems. Firstly, to present the cloud platform planning method. The modelling and linear optimization algorithm for the prosumer’s self-balanced to minimize the cost with trading quantity and random bidding price are proposed. Secondly, the key technologies to realize the information collection and interaction, and data model management are summarized on the basis of the demonstration project, faced to be urgently solved. Thirdly, P2P trade for small and medium scaled communities affected by grid’s time-of-use tariff for prosumers are discussed. The MATLAB simulation with the bidding price following uniformly distributed sampling is taken to analyze the consumers’ benefits and behavior... [more]
Research on Fault Diagnosis of Steel Surface Based on Improved YOLOV5
Weimin Liu, Yao Xiao, Aiyun Zheng, Zhi Zheng, Xiaojie Liu, Zhen Zhang, Chen Li
February 21, 2023 (v1)
Keywords: deep learning, fault diagnosis, fluid components, steel surface, YOLOV5
Steel is an important raw material of fluid components. The technological level limitation leads to the surface faults of the steel, thus the key to improving fluid components quality is to diagnose the faults in steel production. The complex shape and small size of steel surface faults result in the low accuracy of the diagnosis, and the large size of the network leads to poor real-time performance. Therefore, aiming at the problems, an improved YOLOV5 is proposed. Firstly, to reduce the feature information loss, coordinate attention is used to improve YOLOV5, thus the diagnosis ability can be improved. Secondly, to further reduce the loss, a new connection is constructed in YOLOV5, and the detection ability can also be further improved. Thirdly, to improve the real-time performance of the fault diagnosis, YOLOV5 is improved by the lightweight method ShuffleNetV2, and its size can be reduced. Lastly, to further improve the accuracy, the cosine annealing with warm restarts algorithm is... [more]
Filling Process Optimization through Modifications in Machine Settings
Yanmei Cui, Xupeng Zhang, Jing Luo
February 21, 2023 (v1)
Keywords: bottle filling, machine scheduling, mathematical modeling, one-dimensional rules, process optimization
In this paper, a mathematical model is developed for the modified settings of an automatic filling machine to minimize the filling time of orders for different volumes of dairy product and flavors. The linear programming model is solved using the Simplex method to find an optimal solution to the optimization problem. The results of the model are used for sequencing the processing of orders using one-dimensional rules with the aim of obtaining an optimal sequence for the most valued performance measure. The comparative analysis of the one-dimensional rules showed that Shortest Processing Time (SPT) is better than the other rules for minimization of the average time past due. Additionally, the results of the model for the new machine settings, when compared with previous similar studies, yielded encouraging results.
The Influence of Solvent and Extraction Time on Yield and Chemical Selectivity of Cuticular Waxes from Quercus suber Leaves
Rita Simões, Isabel Miranda, Helena Pereira
February 21, 2023 (v1)
Subject: Materials
Keywords: cork oak, cuticular wax, lupeol, solvents, terpenes
The cuticular lipid compounds, usually named cuticular waxes, present in the cuticular layering of Quercus suber adult leaves were extracted with solvents of different polarities (n-hexane, dichloromethane and acetone) and analysed by GC−MS. Q. suber leaves have a substantial cuticular wax layer (2.8% of leaf mass and 239 μg/cm2), composed predominantly by terpenes (43−63% of all compounds), followed by aliphatic long chain molecules, mainly fatty acids, and by smaller amounts of aliphatic alcohols and n-alkanes. The major identified compound was lupeol (1.2% of leaves in n-hexane extract). The recovery and composition of cuticular lipids depended on the solvent and extraction time. The non-polar or weak polar solvents n-hexane and dichloromethane extracted similar lipid yields (77% and 86% of the total extract, respectively) while acetone solubilised other cellular compounds, namely sugars, with the lipid compounds representing 43% of the total extract. For cuticular lipids extraction... [more]
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