bluuebunny/crossref_metadata_2025_split huggingface dataset:
Design and performance analysis of a retractable electric vehicle based on modern numerical simulation theory
Authors: Zhang Yuanyuan , Xin Jianghui , Zhao Zhendong 
Published: September 2019

Abstract
In view of environmental pollution, energy shortage and urban traffic congestion and other issues, a drawer type retractable electric vehicle (REV) is designed. Through the establishment of the frame and the vehicle’s three-dimensional entity model, the frame of the static characteristics and modal characteristics are analyzed by using the finite element numerical simulation theory. The results show that the frame vertical stiffness is not reasonable, thereby improving the frame structure. Based on multi-body dynamics theory, the vehicle dynamics model is established, and the ride comfort of the vehicle is checked. The results show that the comfort of the vehicle is in line with the general requirements of the vehicle. The design and analysis method of this paper has enriched the design method of modern electric vehicle, which can embody the characteristics of light weight, clean energy, effective space utilization and so on, as well as has certain engineering application value.
Experimental study on the natural frequency of tunable piezoelectric cantilever plate
Authors: Chen Lihua , Chang Liqi , Xue Jiangtao , Yang Fenghong 
Published: September 2019

Abstract
PEH (piezoelectric energy harvester) outputs a higher voltage when the natural frequency matches ambient vibration frequency. How to widen working frequency band is a hot issue in study of PEH. In this paper, an auto-tuning PEH is presented by attaching a box to each corner of its free sides and a ball is placed in each box. Change of the balls position makes natural frequency of PEH variable, which expands working bandwidth of the device to accommodate complex ambient vibration. Fixing the equipment on experimental platform by designing fixture, hammering experiments are carried out to measure natural frequency of the structure when balls are in different positions. It is found that the maximum and minimum natural frequencies exist in the auto-tuning PEH, which form a resonance bandwidth. Moreover, there are multiple position combinations of two balls at the same natural frequency in the range of resonance bandwidth. Fixed the apparatus on exciter by the fixture, and a constant excitation frequency is selected in the bandwidth to perform auto-tuning experiments on the instrument. It is observed that location of balls is automatically changed to make natural frequency of the system coincide with the excitation, and the law of variation in balls position is obtained. The converter is subjected to sweeping experiments through an exciter and an oscilloscope. Using voltage-frequency diagrams, it is shown that the auto-tuning PEH outputs a higher voltage and its frequency band is wider when the ball rolls freely compared to two cases where balls are fixed.
Orbital transport system - the concept and mechanics of orbital motion
Authors: Chen Danhe , Koryanov Vsevolod V. , Kazakovtsev Victor P. , Zhang Budang 
Published: September 2019

Abstract
A brief introduction to the meaning of on-orbit services and research on space-based services is provided in this work. In the context of on-orbit service, the near-circular orbit is idealized as a disturbed circular orbit, and a general equation for the optimal maneuver of the near-circle orbit is presented. The examples of coplanar on-orbit services in low, medium and high orbits are analyzed respectively, and the best maneuvering scheme for orbit transfer is solved by special software. Further analysis of the impact of different heights of parking orbit on the optimal maneuvering scheme reveals that the closer parking orbit to the target orbit, the less energy is required for maneuvering, but the phase-modulation time and the transport capacity of the launch vehicle should be considered comprehensively.
Effect of temperature cycling on performance of epoxy resin and evaluation of state
Authors: Chen Xiwen , Lu Bing , Zhang Dandan , Zhang Jun , Chen Jingting 
Published: September 2019

Abstract
Epoxy resin samples were prepared according to the most common types of epoxy resins and curing agents in the market. The material was temperature-circulated at -40 to 150°C to investigate the effect of temperature cycling on the dielectric properties and bending properties of the material. The results show that with the increase of the number of temperature cycles, the relative dielectric constant, dielectric loss, flexural strength and flexural modulus of epoxy resin increase first, then decrease and then increase, and the electrical conductivity increases. Based on the samples of various performance values of epoxy resin in different times, an evaluation model based on BP neural network was established to evaluate the state of epoxy resin.
Predictive direct torque control for permanent-magnet synchronous machines based on duty ratio modulation
Authors: Guo Tingting , Deng Lihui , Miao Zichao 
Published: September 2019

Abstract
In this paper, Two-step model predictive control based on duty ratio modulation of permanent magnet synchronous machine (PMSM) is proposed. There is a large amount of computation in the two-step predictive control. In this paper, a fast vector selection method is proposed to solve the problem of computational complexity. The proposed voltage vector selection method avoids the complete enumeration for testing all feasible voltage vector, and the calculation method of duty are discussed. This control method achieves a constant switching frequency, and the torque fluctuation is smaller, inheriting the advantages of predictive control response speed. To investigate the effectiveness of the proposed method, two-step predictive direct torque control based on duty ratio modulation (TSPTC-DM), comparison of one-step predictive direct torque control based on duty ratio modulation (OSPTC-DM) and finite control set model predictive torque control (FCS-MPTC) is shown.
Error analysis for the rate azimuth platform INS
Authors: Wang Fenglin 
Published: September 2019

Abstract
To lower the cost of passive gravity navigation and dynamic gravity measurement, a rate azimuth inertial platform with a gravity sensor on it was put forward to compose a navigator with gravity measuring. Some research about this rate azimuth platform inertial navigation system was carried out, the rate azimuth horizontal reference frame and actual platform reference frame were set up, the error equationuations, which including position error, velocity error, platform angle error, course error were put up, which would contribute to the integrated system, and the simulation of error for the rate azimuth inertial platform was shown of system errors was shown.
Semi-captiveperiod projectile motion gesture test system
Authors: Zhang Feimeng , Huang Xin , Zhang Chongjie 
Published: September 2019

Abstract
A newly active photoelectric testing approach is introduced in this paper to effectively tackle the pressing problems of artillery testing, considering the current existing problems of semi-captiveperiod projectile motion gesture test. This testing system is composed of seven parts, whose test error is no more than 0.1’, achieving advanced level in this domain.
Capacitive sensor and its calibration- A technique for the estimation of solid particles flow concentration
Authors: Abrar Usama , Shi Liu , Jaffri Nasif R. , Li Qin , Omar Mian W. , Sindhu Hassan R. 
Published: September 2019

Abstract
The precise and accurate measurement of flow rate in the batch flow of the solid particles is of primary importance in many process industries for the improvement of the efficiency of the system. Many techniques developed for the measurement of mass flow rate. The capacitive sensors has a significance of being non-invasive, higher accuracy and low cost for mass flow measurement despite the fact that many factors adversely affect the performance- including non-uniform flow, multiphase flow, temperature, pressure, and moisture in the solid particles. This paper covers preliminary investigations of the offline estimation of mass flow concentration based upon the calibration of capacitance electrodes to quantify the mass of dielectric as a function of capacitance variation between the electrodes.
Modeling and simulation of constant current converter in energy branch unit
Authors: Tian-shu Wu , Xue-jun Zhou , Zheng Zhang , Xi-chen Wang 
Published: September 2019

Abstract
As an important part of electric energy branch unit, constant current converter has the characteristics of simple structure and high efficiency. In this paper, a constant-current converter used in underwater power branching unit is modeled and simulated. The model of constant-current converter circuit is established by using state space method, and the steady-state operating point of DC is calculated. Based on the model, maximum impulse current and drain-source voltage of switching transistor in constant current converter are studied. The simulation test of constant-current converter is carried out by Saber simulation software. The results show that the circuit efficiency can be maintained above 90% while the reliability of the converter is guaranteed, which provides a theoretical basis for the analysis and research of efficient and reliable underwater power branch units.
Development of scroll vacuum pump characteristics by thermal deformations compensation
Authors: Burmistrov A V , Salikeev S I , Raykov A A , Tyurin A V 
Published: September 2019

Abstract
Influence of thermal deformations of scroll vacuum pumps working elements on clearances in working mechanism is considered. Analysis of influence of a clearance value on indicator diagrams and pumping speed was carried out. It is shown that alteration of a clearance due to thermal deformations decreases pumping speed at low pressures. The design of scroll elements compensating clearances alteration in pump operation and improving pumping characteristics is presented.
Effective sputtering yields of alloys chromel and kopel with argon ions in magnetron sputtering system
Authors: Dukhopelnikov D V , Riazanov V A , Plotnikova O P 
Published: September 2019

Abstract
This article presents the results of research on sputtering of thermoelectric alloys chromel and kopel. Sputtering was performed in argon atmosphere with magnetron sputtering system. Results of this work can be used in creation of thin-film thermoelectric generators.
Calculation features of the magnetic and temperature fields of planar magnetron system when sputtering magnetic targets
Authors: Goncharov V D , Yashkardin R V 
Published: September 2019

Abstract
Mathematical model for temperature fields calculation in targets of magnetron sputtering systems is described. The paper shows the main ways in which the power supplied to the discharge is removed. The results of numerical simulation of the spatial temperature distribution of a magnetic target are presented. The paper also shows the results of numerical simulation, which allow to link the input power and the shape of the target with the distribution of its temperature. For the obtained temperature distributions magnetic induction distributions are calculated taking into account the loss of magnetic properties of a material when its temperature exceeds the Curie point.
Development of a temperature controlled container for high accuracy capacitance manometers
Authors: Kangi R 
Published: September 2019

Abstract
National Institute of Metrology of Turkey (UME) has developed a new temperature-controlled container for high accuracy capacitance manometers (CDG). In the proposed design, due to the direct (metal-metal) contact of the temperature-controlled plate of the container with the aluminum shell of the sensor, the influence of the temperature of the electronics on the pressure sensor is minimized. Inside the aluminum shell, the temperature of the pressure sensor can be controlled at any fixed temperature with stability of ± 2 mK in the temperature range from 15 °C to 30 °C. The use of a pressure sensor inside an appropriate container minimizes the effect of the ambient temperature on the sensor, eliminates the need for correction for the effect of thermal transpiration and thus improves sensor accuracy. CDGs inside containers showed excellent short-term stability at zero pressure, which does not exceed ± 5 mPa as well as a maximum drift rate of 0.03 mPa h−1. The measurement results of ambient temperature influence on CDG’s zero showed a maximum change of 0.001% of full scale per degree Celsius. Control of CDG at ambient temperature significantly reduces the effects of thermal transpiration, which increases slightly to a maximum of 0.3% at the lowest pressures.
Dynamic properties of a glow discharge in long tubes
Authors: Kiselev A S , Menshchikova V V , Seyfulina N A , Smirnov E A 
Published: September 2019

Abstract
The impedance of a glow discharge in narrow long tubes characteristic of gas-discharge lasers is investigated. An expression for the impedance is obtained taking into account the falling character of the current-voltage characteristics, the dynamic properties of the positive table and the cathode region. Satisfactory consistent calculated and experimental results are achieved.
Development, synthesis and production of multilayer thin-film filters for infrared sensors for monitoring of flammable gases and vapors of flammable liquids
Authors: Makeenkov A A , Baranov A M 
Published: September 2019

Abstract
We present the results of development and production of multilayer thin-film filters for infrared sensors for monitoring of flammable gases and vapors of flammable liquids. This paper addresses technological peculiarities of their production. A theoretical simulation of multilayer filter parameters to provide the transparency in wavelength range 3.3 - 3.5 μm was carried out. It is demonstrated that spectral characteristics of produced multilayer filter correspond to the calculated ones.
I-V characteristics of magnetron with hot titanium target sputtered in argon-oxygen mixture
Authors: Minzhulina E A , Shapovalov V I , Aslan N , Shestakov D S 
Published: September 2019

Abstract
The discharge current-voltage characteristics of a dc magnetron with a single hot titanium target in Ar + O2 environment are studied. It was found that the I-V characteristics measured in the range of current densities of 10-200 mA/cm2 have three inflection points and a maximum. The competition of several processes can cause the discovered features. In the oxide target operating mode, these processes include the chemical reaction for the formation of oxide on the surface of the target and its sputtering by argon ions. In the metal mode, gas rarefaction near the target and thermionic emission compete.
Optical and mechanical properties of fluorocarbon coatings formed in a matrix mode of deposition using an atmospheric pressure plasmatron
Authors: Shvedov A V , Elinson V M , Shchur P A , Kirillov D V 
Published: September 2019

Abstract
This paper is devoted to study of the formation of fluorocarbon coatings, which were obtained by using a low-frequency plasmatron of a low-temperature plasma at atmospheric pressure. The possibility of forming fluorocarbon coatings on silicon, and PET and polystyrene substrates is shown. The spectra of the UV and visible ranges were obtained, the width of the band gap of the obtained coatings was established by the Tauc method. The nanohardness of the obtained coatings was studied by the Oliver-Farr method.
Thermal stability, mechanical and tribological behavior of Ti-Al-Si-N ion-plasma coating
Authors: Volkhonskii A O , Belov D S , Demirov A P , Shestakov V M , Kiselyov T V 
Published: September 2019

Abstract
It is shown that the elemental and phase composition does not change, and the architecture with clearly defined layer boundaries is preserved when annealing the amorphous-nanocrystalline Ti-Al-Si-N multilayer coatings in the vacuum at temperatures of 700-1100 °C. At the same time, the coherent scattering regions of X-ray radiation increase from 8.5-9.5 to 11-12 nm while the microstrains in the crystal lattice decrease from 1.1 to 0.6-0.7%. Structural changes are accompanied by a slight decrease in hardness. Thermal treatment does not change the nature of cohesive fracture of coatings and does not affect their adhesive strength. The decrease in wear resistance after thermal treatment of coatings, manifested in the increasing wear and friction coefficient, is probably due to the changing nature of the cohesive fracture accompanied by the appearance of large fragments that act like high-abrasive particles between friction surfaces. Ti-Al-Si-N coating is characterized by partial oxidation when heated in air up to 800 °C and complete nitride phases transition to oxides and oxynitride compounds at 900 °C.
Experimental Investigation of Aluminum Graphite and MOS2 Composite Materials
Authors: Malaiyappan Prakash , Vignesh S. 
Published: September 2019

Abstract
Metal Matrix Composites (MMCs) have light weight, high quality, firmness and display more prominent protection from consumption, oxidation, and wear. In this investigation half and half Aluminum network composite was created through blend throwing course. Molybdenum disulfide (MoS2) and graphite (Gr) particles were utilized as fortification stages for the present investigation. Three grinding material examples were created dependent on a trial detailing, and vol. % graphite + vol. % MoS2, individually.
Mechanical behavior of nanoparticulate TiO2 reinforced magnesium matrix composite
Authors: Radhakrishnan Ganesh , Anirudh P V , Anujan Kumar S 
Published: September 2019

Abstract
In this study, nano-sized titanium dioxide particulate reinforced pure magnesium matrix composite has been fabricated by powder metallurgy technique for five different weight fractions of reinforcement such as 4 wt%, 8 wt%, 12 wt%, 16 wt%, and 20 wt% respectively. Samples of these compositions are iso-statically cold compacted into cylindrical specimens of diameter and length each 15 mm respectively, followed by sintering and hot extrusion with an extrusion ratio of 1.56:1. SEM micrographs of blended composite powders before compaction confirmed the uniform distribution of reinforcement throughout the matrix without any agglomeration. Microstructural analysis of extruded specimens revealed the refined matrix grains and grain boundary. The reinforcement may interrupt the matrix grain growth on grain boundaries during extrusion. Targeting for biomedical applications like bone implants, kneecap surgery etc., the mechanical behavior of the composite such as microhardness, and compressive strength have been studied. It was observed from the study that the mechanical properties have been significantly improved by adding reinforcement compared to pure magnesium and better mechanical behavior have been noticed for composite with higher contribution of reinforcement.
Experimental and Numerical Study on Modified Vertical Axis Wind Turbine
Authors: Abraham Eben Andrews A. , Karthick P , Allan Jeraled A. , Anuroop K , Chidanand G 
Published: September 2019

Abstract
Wind energy is very important in the development of sustainable energy with the growing focus on renewable energy; interest in design of wind turbines has also been expanding. In today’s market, the horizontal axis turbine is the most common type in use; Experimental data of this research is to compare the CFD Analysis with the Experimental Data of hybrid Modified vertical axis wind turbine. The graphical data based on the parameters such as Velocity, Power Coefficient, Tip Speed Ratio Vs Power Coefficient and Wind Velocity Vs Power Coefficient, which are discussed in this research. The Savonius turbine (Lift Turbine) was attach with the Gorlov turbine (Drag driven turbine) for the self-starting of the hybrid-modified turbine. Here the design, construction and testing of vertical axis wind turbine with three blades, starting solely from low energy of the wind. The velocities such as 5, 7, 9 and 11 m/s are tested in CFD Analysis for checking from which maximum power can be extracted so it can be used in desert area.
Comparative Analysis of Different Surface Modification Processes on AA 7075 T651
Authors: Abeens M. , Muruganandhan R. , Thirumavalavan K. 
Published: September 2019

Abstract
Modern industries turn into light weight high strength materials. Aluminum alloys are having such a great property, in which, AA 7075 T651 provides good strength than other alloys. Hence, hardness of aluminum alloys are poor there by improvement of surface hardness of aluminum alloy is necessitate. Shot peening, severe surface mechanical treatment (SSMT) and laser shock peening (LSP) are the surface property enhancement processes, which are used to improve the surface hardness of AA 7075 T651. This article deals with study the effect of shot peening, Severe surface modification process and laser shock peening on AA 7075 T 651. Among these two processes, LSP reveals better improvement in surface hardness. The Vickers micro hardness test is contacted on the specimens. 15%, 18% and 29% of harness improvements are obtain than unpeened specimen in shot peened specimen, SSMT specimen and Laser shock peened specimen respectively. The deformed layer thickness is 500 µm found in the laser shock peened specimen and 300 µm in the shot peened and SSMT treated specimens.
An investigation on laser induced downward expanded vapour region in laser weld butt joint of AISI 316L stainless steel
Authors: Jayanthi A. , Venkatramanan K. , Suresh Kumar K. 
Published: September 2019

Abstract
The physics of laser - AISI 316 stainless steel interactions discussed stage-by-stage including the formation of plasma plume around the keyhole during the laser welding. This work reveals that the pulsed laser heat input is a highly successful tool to join 2 mm thick 316L stainless steel welding by a single pass, that too autogenously! However, inadequacy in laser input power leads to the incomplete penetration at weld joint and poor bead formation and whereas excess heat input causes root concavity (loss of material) at the bottom. It has observed a vapour region near bottom of the keyhole while the joint fully penetrated and it slightly expanded due to excess heat input, known as downward expanded vapour region. Consequently, downward expanded vapour region results in excess melting; it leads to loss of material by spatter during welding that causes root concavity at the bottom, which will affect the joint integrity. Therefore, it is important to identify and control the expansion of vapour region by optimizing the input power of the laser. To ensure optimization of the operating parameters and the integrity of weld joints are qualified through Vickers micro hardness test and X-ray radiography test.