bluuebunny/crossref_metadata_2025_split huggingface dataset:
Study of dynamic properties of measuring equipment at the design stage
Authors: Sytko I I , Makhov V E 
Published: January 2021

Abstract
The modeling of measuring tools was carried out based on modern computer technologies in VisSim and Mathcad software. The transfer function of a measuring instrument in a closed state with negative feedback is determined. The range of changes in the feedback coefficient at which the dynamic system is stable is determined. The optimal feedback coefficient is determined by the criterion of the transition process minimum duration. The quality indicators of the measuring instrument are determined by the transition function: the time of setting (regulation), over-regulation, the number of fluctuations and the degree of attenuation. The transfer function of the measuring instrument is determined by error. The error rates for steady state position, speed and acceleration are obtained by decomposing the Taylor series of the transfer function by mistake in the Mathcad environment, using the series function. The stability reserves in amplitude and phase are determined before and after introduction of corrective links to the structure of the measuring instrument. The sequential regulator corrective link was synthesized according to the criterion – minimization of stabilization time. The serial controller parameters were calculated in Mathcad by gain coefficient interactive selection and time constant, with the ability to control its parameters by logarithmic frequency characteristics, as well as by static and dynamic properties in transient and steady-state modes. The dynamic safety is determined when one of the measuring tool parameters deviates from the nominal value.
Development of PLIC-based time synchronization device
Authors: Tynchenko V S , Kukartsev V V , Cherepanov A I , Petrenko V E , Dzhioeva N N 
Published: January 2021

Abstract
The article discusses a method of receiving and processing signals using a programmable logic integrated circuit in order to reduce the cost of time synchronization equipment. These actions are considered by the example of the «Beta» time signal. A method for receiving and processing a signal is described, based on the given structural diagram of the project. The installation was assembled and an experiment was conducted in accordance with the described parameters. The data obtained during the experiment in the form of graphs (spectral analysis of the signal, decoding of the Morse code and the information structure of the signal) are also presented. According to the results of the experiment, it is clear that the received signal from the “Beta” exact time service radio transmitter was received and processed without loss, as evidenced by the spectral analysis, as well as further decoding of the signal. The device fully complies with the set conditions and can be used in banking, metrology, as well as mobile operators, which will significantly reduce their costs. The assembled installation can be used in banking, metrology, and also by mobile operators, which will significantly reduce their time synchronization costs.
Development of methods for determining the density of low-melting metals
Authors: Dadashev R Kh , Kutuev R A 
Published: January 2021

Abstract
Features of the formation and development of scientific research in the laboratory of physics of interfacial phenomena in ChISU named after L. N. Tolstoy in the 1970-1980s of the last century are considered in this paper. Particular attention is paid to the development and improvement of various methods for measuring the density of liquid metals and alloys. We determined the contribution of ChSU scientists in the study of metals and alloys properties and gave a scientific assessment of the obtained results. The development of methods and techniques for measuring the density of liquid metals and alloys went in two directions. Primarily, we took significant steps towards improving the accuracy of density measurements. The instruments were designed in which the accuracy of measuring density and, in particular, the temperature coefficient of density was significantly increased. Foremost, this concerns advanced pycnometers and areometers designed in ChSU laboratories. The instruments received inventor’s certificates, and they were awarded the bronze medal of the Exhibition of Achievements of National Economy in 1977. The second direction improving the measuring technique of the metal properties is characterized by instrument designing for the joint measurement of physico-chemical properties in the same thermal vacuum conditions. Both areometers and pycnometers were used to determine density in these instruments.
Steady tangential control jet for improving the effectiveness of a rudder under one-engine inoperative condition
Authors: Leelaburanathanakul P , Virangkur V , Wangsiripaisarn T , Pitakarnnop J , Bunyajitradulya A 
Published: January 2021

Abstract
The aim of the research is to numerically investigate the use of a steady tangential control jet (CJ) at the hinge of the vertical stabilizer as an active flow control (AFC) technique to improve the effectiveness of a rudder on a subsonic aircraft during one-engine inoperative (OEI) condition by keeping the flow attached to the control surface. The goals are in two folds: firstly to investigate the effects of CJ parameters, specifically the jet-to-freestream velocity ratio (rV
) and the jet slot height ratio (rH
), on the vertical stabilizer performance, and secondly to find the optimum CJ condition that yields the improved and optimal performance. In this regard, the optimal condition of the CJ is prescribed as the condition that gives the maximum side force to drag ratio under the requirements that the required minimum trim side force can be achieved and there is an improvement in control surface margin for yawing motion. The investigation is carried out through computational fluid dynamics (CFD) using the Spalart-Allmaras turbulent model. Under the optimal CJ condition, its implementation can provide the required minimum rudder side force coefficient (Cy, trim
) of 1.19 at a rudder drag coefficient (Cd
) of 0.0013, a decrease in drag coefficient of 95% over the baseline case of plain flap without CJ. In addition, there is an improvement in rudder margin with the maximum side force coefficient increase by 42%, and the corresponding drag force coefficient decrease by 25% for the aircraft to yaw in a direction of the still-active engine.
Determination of Strong Factor in Bird Strike Analysis using Taguchi`s method for Aircraft Manufacturing guide
Authors: Mathaiyan Vijayakumar , Vijayanandh R. , Jung Dong Won 
Published: January 2021

Abstract
Bird strike analysis is of great importance because of the loss it can create. Since there are many factors which influences the level of damage, the computational cost for determining the strong factor is high. Usage of the optimization techniques will give the significant reduction of computational cost. Taguchi method is used to find out the strong factors for a detailed study of bird strike effects on the Aircrafts. This can help the engineers to manufacture the structure free from or have relatively less damage because of the bird strike.
Honeycomb structures manufactured by a new method and its failure analysis
Authors: Wang Lijun , Saito Kazuya 
Published: January 2021

Abstract
Nowadays, honeycomb sandwich panle is widely used in the field of aircraft and spacecraft, due to its light weight, high strength and good impact resistance. So the stability and buckling behavior of the structure are crucially important. In the present work, two type aluminum honeycomb sandwich panles were manufactured by a new manufacturing method (i.e. a press and folding process). To evaluate the structural failure of the panle, the three-point bending test was carried out, and found that the face sheets and the honeycomb core were splited open under a local load, but the panle has not been completely failure. In addition, the buckling behavior of the panle was implemented with finite element analysis (FEA).
Numerical Investigation of Fluid Flow, Characteristics of Thermal Performance and Enhancement of Heat Transfer of Corrugated Pipes with Various Configurations
Authors: Al-Obaidi Ahmed Ramadhan , Alhamid Jassim 
Published: January 2021

Abstract
The flow characteristics pattern and heat performance improvement have been analysed by applying the computational method in 3D corrugated configuration tubes. Configuration were carried out with varying geometrical parameters, counting various ring corrugated angle over a tube at several Re range between 4000 and 12000. Computational outcomes in this investigation were validated with available experimental data. Outcomes noted that there was a significant alteration in the behavior of flow structure hence an important rise in pressure losses and enhancement in thermal performance due to using corrugated configurations when compared with the normal plane pipe. By utilizing the latter tube under varying parameters, it produces more turbulence flows, separation, mixing, and more distribution in the boundary flow layer, hence enhancing the thermal flow performance. Furthermore, pressure and Nu were augmented when corrugated configurations rise. Besides, these configuration parameters have a significant impact on the value of overall heat performance. Then the higher value was about larger than 1.65. Computational calculations can provide good results on fluid structure inside the pipe and heat transfer augmentation.
Experimental Investigation of Forced Convective Heat Transfer in Circular Pipe with Wire Mesh Porous Media
Authors: Chanmak P , Krittacom B , Waramit P , Peamsuwan R 
Published: January 2021

Abstract
This experimentation aims to study Nusselt number (Nu) and Friction factor (f) deriving from the forced flow of fluid inside a circular pipe under a uniform heat flux condition. Porous media used in this study is made of stainless-steel wire mesh 304 which has the number of pores per inch (PPI) of 8. Reynolds number (Re) ranges from 3000 – 15000. Distance between two plates of wire mesh (p), ranges from 10-50 mm. The results of the experiment indicate that the Nu figure tends to be higher when there is a rise in Re and a decrease in length of p, resulting in an increase in mass of material. The increasing mass of material enables it to store a large quantity of energy from hot air causing heat to be transferred toward the pipe wall in a higher rate. The value f tends to decline when the Re and p grow up. This phenomenon rather conforms to the general principles of nature, namely that a barrier against the flow will lead to a higher friction factor (f). The Performance Evaluation Criteria (PEC), recorded across the whole Reynolds number range, reaches a maximum where the p is 40 mm since the ratio of Nu to f is the most appropriate figure.
Numerical Analysis of Microstructure Development during Laser Welding Nickel-based Single-crystal Superalloy Part IV: Welding Conditions Optimization
Authors: Gao Zhiguo 
Published: January 2021

Abstract
The thermal-metallurgical modeling of columnar/equiaxed transition(CET), multicomponent dendrite growth and nonequilibrium solidification behavior was further developed during single-crystal superalloy weld pool solidification over a wide range of laser welding conditions (laser power, welding speed and welding configuration). It facilitates the unprecedent understanding of the effect of welding conditions on overall stray grain formation, dendrite trunk spacing and solidification temperature range throughout the weld pool. In order to eliminate the solidification cracking through microstructure control, it is imperative to optimize the welding conditions for successful defect-free laser welding. Crystallographic orientation of dendrite growth plays an important role than heat input in microstructure development and solidification cracking susceptibility. Optimum low heat inputs (low laser power and high welding speed) of solidification condition simultaneously prevent stray grain formation, refine dendrite size and mitigate the solidification temperature range to improve the weldability and weld integrity and vice versa. Nonequilibrium solidification behavior of the weld pool suppresses the solidification temperature range and dendrite size, and improves the solidification cracking resistance. The overall stray grain formation, dendrite trunk spacing and solidification temperature range in (001) and [100] welding configuration are beneficially reduced than that of in (001) and [110] welding configuration regardless of heat input. The theoretical predictions agree well with the experiment results. Moreover, this promising model is also available to other single-crystal superalloys with similar metallurgical properties during laser welding or laser cladding.
Expansion of genetic and morphological approach to synthesis of principles of new clamping device for machine-tools
Authors: El-Dahabi Farouk , Kuznetsov Yuri , Abou-El-Hossein Khaled , Abbas Abdalla , Hweju Zvikomborero 
Published: January 2021

Abstract
This paper describes the use of a genetic and morphological approach employed in the development of a near structural synthesis of a machine-tool clamping cartridges having a mechanism based on the principles of tangential clamp. The study focuses on the design of device capable of holding a number of workpieces having cylindrical and flat shapes at the same time during metal cutting operation. The study reveals that the use of tangential principal clamping may open up new capabilities for the development of workholding devices that can be used to position and clamp few workpieces simultaneously.
Efficiency assessment of ANFIS in surface topology prediction in diamond turning of RSA443 optical aluminum using Small Datasets
Authors: Hweju Z. , Abou-El-Hossein K. 
Published: January 2021

Abstract
This paper presents an assessment of the efficiency of the ANFIS model in surface topology prediction of RSA 443 optical aluminium using small datasets. The experiments are designed and conducted based on the Taguchi L9 orthogonal array. The single point diamond turning procedure has been carried out on Nanoform 250 Precision CNC machine. Cutting speed, feed rate and depth of cut together with acoustic emission signal root mean square, dominant frequency and peak rate are the ANFIS model input parameters. The function that gave the best results was the sigmoidal membership function, hence it is used in this paper. To evaluate model performance, the measured surface roughness results are compared to ANFIS predicted results based on the Mean Absolute Percentage Error (MAPE) and prediction accuracy. The MAPE values show that the ANFIS prediction accuracy of surface topology is 79.42%. This value is within the upper quartile range, indicating the high predicting accuracy of ANFIS even in the absence of enough training data. The model can be reliably utilized in surface roughness prediction using small datasets while its prediction accuracy can however be improved by using larger datasets.
Flooding Control Mechanism of Waterflooding Sweep Control Technology
Authors: Yinzhu Ye , Xiaodong Kang , Baoshan Guan , Xianjie Li , Zhe Yang , Ke Hu , Xingcai Wu , Peiwen Xiao , Shichao Li , Yang Liu 
Published: January 2021

Abstract
In view of the problems of high permeability, high water cut and high recovery in offshore heterogeneous oil fields, the system including cross-linked polymer gel and flexible microgel gel was prepared indoors, which was used in the experiments of classified combination of waterflooding sweep control technology. The SMG microscopic oil displacement experiment shows that after the SMG system is injected into the model, the speed of the displacement fluid in the large pores decreases and the speed of the small pores increases, thereby effectively improving the oil recovery in the small pores. The long core experiment with multiple pressure points proves that the driving method of that cross-linked polymer gel and flexible microgel gel are alternately injected into core, which can block the dominant channel step by step and start. Then the low permeability area was displaced and the displacement fluid continuously diverted in the core, thus maximizing the purpose of oil recovery. The classification and grading water flooding control technology method provides effective technical support for the optimization of process parameters of offshore oilfield.
The introduction and comparison of two techniques of fluid transport at the microscale
Authors: Jiang Kaiyue 
Published: January 2021

Abstract
With the development of human society, people’s level of science and technology is also improving. In the process of continuous exploration, people often find some new unknown areas. Although we are very unfamiliar with these uncharted areas, they can have a significant impact on our lives, such as the field of microfluidics. It can perform small tasks at the micro and nano level, reducing our resource consumption, reducing some of our risks, but increasing our safety and new application tools. The exploration and development of the field of microscopic fluids can bring great help to our lives, especially in medicine, and significantly increase our surgical success rate. This article is summarized by analyzing and comparing the academic research of many experts. In this era, the role of the microfluid field is still significant.
Modification and Properties of EVA Foamed Material with Hemp Stem Powder
Authors: Guo Yafei , Hao Xinmin , Liang Gaoyong 
Published: January 2021

Abstract
In this study, a certain amount of hemp stem powder was added into ethylene-vinyl acetate (EVA) copolymer foam system by molding, and the improvement of properties of composite foam system with different hemp stem powder content of 0-30% was studied. The results showed that hemp could decrease the hardness and density of the composite foam system, improve the resilience and compression deformation rate, and have excellent moisture absorption and quick drying properties and antibacterial properties. The results show that the foaming system with 10% - 20% hemp stem powder has the best comprehensive mechanical properties, which can be used in shoes.
Effect of multi-phase STF on the high-speed impact performance of shear-thickening fluid (STF)-impregnated Kevlar Composite Fabrics
Authors: Wang Fadong , An Chao , Jia Qingxiu 
Published: January 2021

Abstract
Shear thickening is a non-Newtonian flow behavior, characterized by an increase in viscosity with the applied shear rate. Due to this superior performance of shear thickening fluid (STF), it has received a great deal of attention in the field of armor protection. In this paper, the properties of nanoscale silica STF systems are modified by the addition of nanocellulose (CNF). The rheological properties of the prepared STFs were tested. Kevlar fabrics were immersed in multiphase STF solutions to make STF/fabric composites. The results showed that the addition of nanocellulose (CNF) enhanced the steady-state and dynamic aspects of the shear-thickening fluid. The rheological properties of the shear-thickening fluid were strongest when the content of nanocellulose added was 0.2%, and the single yarn extraction force of the Kevlar composite was much stronger than that of the pure Kevlar without STF. The CNF-modified STF enhances the impact resistance of the composite.
Preparation of functionalized graphene/thermal conductive polyurethane films
Authors: Luo Zuhuo , Yan Jie , Chen Danqing 
Published: January 2021

Abstract
Graphene/polymer composites have been widely used as thermal conductive materials in electronic equipment. However, the development of advanced graphene thermal conductive composites faces many problems, such as easy agglomeration, high interfacial thermal resistance and poor mechanical properties. In our work, new graphene-based polyurethane thermal conductive composites based on octadecylamine (ODA), graphene and thermoplastic polyurethane were prepared. The thermal conductivity(λ) of the composites reached 1.46W/(mK) with loading 20wt.%mRGO, which was increased by 326.02% compared with that of TPU.
Effect of sintering insulation time on the properties and microstructure of graphite-copper composite
Authors: Zou Haiping , Yu Xiaohong , Wu HongLiang 
Published: January 2021

Abstract
The copper powder and graphite powder were used as raw materials to fabricate the graphite-copper composite by low temperature cold pressure powder metallurgy sintering method. The powders were mixed by ultrasonic dispersion and mechanical ball grinding process. The effects of sintering insulation time on the properties and microstructure of graphite-copper composite were investigated. The result showed that the distribution of graphite on the copper matrix was uniformly and formed a good interface by using the ultrasonic dispersion and mechanical ball grinding process. When the sintering insulation time was raised from 3 hours to18 hours, the friction coefficient and wear rate were decreased in the initial stage (from 3 hours to 12 hours) meanwhile the Vickers hardness (HV0.5) reached its maximum value 61.9HV when the sintering insulation time was 12 hours. The SEM (scanning electron microscope) images indicated that the increased sintering insulation time was helpful to distribute the graphite phased in composite relatively homogeneous with the sintering insulation time within 12 hours. However, the properties of graphite-copper composite also showed a downward or stable trend with the sintering Insulation time increasing from 12 hours to 18 hours.
Study on the Modeling and tensile performance simulation of knitted fabric-based conductive line
Authors: ZHANG Chengkun , XIAO Yuan , Qian LI 
Published: January 2021

Abstract
Aiming at the problem of easy breakage and low tensile performance during the preparation of flexible conductive lines on the fabric surface, numerical simulation methods are used to establish a medium-scale three-dimensional (3D) model of the knitted fabric-based conductive line. The influence of the shape and width of the conductive line on the tensile properties is studied, and the deformation and fracture processes of knitted fabrics and conductive lines under different stretching directions (horizontal, vertical, and shear) are clarified. The results show that the optimal geometric shape of the conductive line is horseshoe shape, the width of the conductive line is inversely proportional to the tensile performance, the crack section of the conductive line is straight when stretched horizontally, and the cross-section of the crack is sawtooth when stretched vertically, the initial stage of the crack section during shear stretching is the same as that of horizontal stretching, and the later crack development is irregular.
Evaluation of dynamic mechanical and cytotoxic properties of electrospun poly (lactic acid)/cellulose nanocrystalline composite membranes
Authors: Wang Fadong , Zhou Mengjiao , Jia Qingxiu 
Published: January 2021

Abstract
In this paper, polylactic acid (PLA)/cellulose nanocrystalline (CNC) composite fiber membranes were prepared by electrospinning technique. The microstructure of the fiber membranes produced was all transformed from a smooth surface to a nanoporous surface by varying the CNC loading level. The influence of CNC content on the morphology, thermal dynamic properties, and cytotoxic properties of PLA/CNC composite nanofiber membranes was characterized. The results show that water molecules can enhance the hydrogen bonding networks between PLA and CNC. when the cellulose nanocrystal content is less than 10%, the composite membranes have good dynamic mechanical properties and no significant cytotoxic effect.