bluuebunny/crossref_metadata_2025_split huggingface dataset:
The Aero-elastic-wake Coupling Behavior for a Two-wind-turbines Case with Power Control Process
Authors: Ma Zhe , Lei LiPing , Zeng Pan 
Published: May 2020

Abstract
This study focuses on the aero-elastic-wake coupling behavior of wind turbines. A newly developed code called FALM (Flexible Actuator Line Model), which combines the wake simulation ability of the actuator line mothed (ALM) and the structural simulation ability of the flexible multibody dynamics method, was employed to achieve these simulations. The power output and thrust, the natural frequency and deformation and the wake characteristics of a single NREL 5MW wind turbine were studied to validate this code. It shows that nonlinear effects such as spin softening and stress stiffening were fully considered by FALM and it can also guarantee a reliable prediction of power and thrust of wind turbines. Furthermore, a case of two-wind-turbines with the inlet wind speed of 14m/s (exceeding the rated wind speed) were carried out to study the aero-elastic-wake coupling behavior in a wind farm. It shows that FALM is able to simulate multiple wind turbines with power control system involved. The pitch control process of the upstream wind turbine was predicted and the dynamic loads of the downstream wind turbine caused by the wake effect were studied. These results will contribute to the study of reducing the fatigue load caused by wake effect.
Research on Automatic Manual Transmission of Pure Electric Vehicle
Authors: Niu Qinyu , Men Hao , Yang Rong 
Published: May 2020

Abstract
In recent years, the electric vehicle industry has developed rapidly. Compared with traditional internal combustion engine vehicles, pure electric vehicles have the advantages of less pollution, less noise, and simple structure. At the same time, the problem of short range has become an important factor restricting the development of pure electric vehicles. This paper proposes to mount a four-speed mechanical automatic transmission in a pure electric vehicle to improve the working efficiency of the motor, thereby improving the vehicle’s cruising range. CRUISE simulation software was used to build a vehicle model of a pure electric vehicle equipped with this transmission. A vehicle equipped with a fixed gear ratio reducer is used as a comparative experiment to study the impact of a mechanical automatic transmission on the economy and power of the vehicle.
Method to Integrate Human Simulation into Gazebo for Human-robot Collaboration
Authors: He Linxi , Glogowski Paul , Lemmerz Kai , Kuhlenkötter Bernd , Zhang Weimin 
Published: May 2020

Abstract
The human-robot collaboration (HRC) takes the advantages of both the flexibility of human workers and the accuracy of robots. Simulation is an effective and economical method to verify the safety and reliability of the HRC system. This paper presents an approach to integrate the simulation of human workers into a robot simulation environment. A digital human model is built in the robot simulator Gazebo and can be controlled by data from proprietary software for human workflow planning. As a result, a holistic HRC scenario is established in Gazebo, which provides the potential for workspace monitoring and robot collision-free trajectory planning based on the Robot Operating System (ROS).
A Novel Comprehensive Model of Wet Clutch During the Engagement Process
Authors: Peng Baoshan , Li Heyan , Liu Jikai 
Published: May 2020

Abstract
With the development of vehicles towards higher power density and reliability, the wet clutch, which is the critical component in transmission system, always encounters the problems of ablation, wear, and breakage. To solve this problem, a novel comprehensive model is developed for the wet clutch to reveal its intrinsic working mechanism. Firstly, a dynamic clearance varying model and a torque balance model are developed for the wet clutch to explain the bearing mechanism along the axial and circumferential directions. After that, the friction coefficient, which varies depending on the interface pressure, slipping speed and temperature, is obtained. By developing the temperature prediction model, a theoretical coupling model is finally established for the engagement process of wet clutch. From the simulation results, the coupling model is sufficient to describe the changing trend of several critical parameters, including the viscous torque, the asperity torque, the contact status on the friction interface, the temperature rise and the friction coefficient, etc.
Analysis of the Vacuum Chamber Based on the Environmental Simulation Experiment of the Lunar Surface
Authors: Zhang Yi , He Chao , Zhang Lei , Han Xiao , Li Qiang , Gu Zhifei , Zhang Pengsong 
Published: May 2020

Abstract
The vacuum chamber based on the environmental simulation experiment of the lunar surface mainly provides the simulation space for the comprehensive environmental effect tests such as vacuum, low temperature, irradiation and charged dust, and provides the interface for the relevant environmental sources, in-situ testing instruments, etc. In this paper, a set of vacuum chamber for the experiment is provided, and the finite element analysis, surface temperature analysis and radiation dose analysis of the chamber are carried out. The analysis results provide a guarantee for the experiment and a reference for the related research work.
Influence of the Clearance of the Transmission Mechanism of the Transmission Characteristics
Authors: XU Jian , FAN Siyi 
Published: May 2020

Abstract
The transmission mechanism is composed of a bearing cover, a rocker arm cover, a rocker arm, a shaft sleeve, a sleeve, a bushing, and a bearing. For a small space and weak rigidity servo drive mechanism, its clearance has a greater impact on static servo characteristics such as swing angle response and loop width. In this paper, the clearance of the transmission mechanism and the play clearance of the bearing are analysed, and the influence on the servo characteristics is obtained.
Immersive Virtual Reality for Fire Safety Behavioural Skills Training via Gesture-based Technology
Authors: Fu Yaqin , Li Qi 
Published: May 2020

Abstract
The fire safety can be one of the biggest problems in metropolitan area. To reduce injuries in a fire, the virtual reality based behavioural skills training (BST) has been used to train people to survive in emergency circumstance. VR-based BST training has been demonstrated to effectively help people of different ages to acquire safe escape skills in a virtual environment. However, most of people have encountered difficulty to train in a right gesture or poor body performance, such as running at unsuitable body position. Gesture-based technology can effectively help people to learn the correct gestures in order to enhance training efficiency. Thus, this paper proposes a theoretical framework of “VR-Gesture BST”, which is expected to improve behavioural skills training more effectively for fire safety training. It adopts motion capture device obtaining user’s body data to evaluate the body performance during the BST training. The outcomes of the study provide guideline and suggestions for VR based design in practice of the behavioural skills training adopted gesture-based technology.
Study on Vibration Characteristics of Cantilever Plate with Annular Mass Frame
Authors: Chen Li Hua , Hou Chao Ran , Cui Shou Jie , Shan Lu Tong , Yang Feng Hong 
Published: May 2020

Abstract
The principle of piezoelectric energy harvester is to convert vibration energy into electric energy, which can supply power for other electronic devices. The actual environment vibration is broadband, random and multi-directional, and the working frequency band of piezoelectric energy harvester needs to be increased, so as to raise energy capture efficiency. In order to increase the numbers of resonance frequencies and widen working band, a new type of cantilever plate structure with ring mass frame is designed. This structure is composed of two anti-symmetrically placed cantilever plates with variable cross-section and additional annular mass. Firstly, the natural frequencies and mode shapes of the system are obtained by modal analysis using the finite element method. Based on modal diagrams, the bending and torsional of cantilever plate and the motion of rigid ring mass frame are considered comprehensively, then the theoretical modal functions of the structure are given. Furthermore, the natural frequencies of the structure are obtained by Rayleigh method. Natural frequencies and theoretical modal functions are verified by comparing with the finite ones, which provides theoretical basis for the analysis of the piezoelectric energy harvester in the future.
Transient Quality Performance Evaluation of Multi-stage Flexible Manufacturing Systems
Authors: Liu Shihong , Du Shichang , Xi Lifeng 
Published: May 2020

Abstract
This paper aims at evaluation of the quality performance of multi-stage manufacturing system during transients. A Markovian method is constructed in order to evaluate transient propagation of quality at multi-stage manufacturing systems which have remote quality information feedback. With the derived Markovian model, analytical expressions of estimating quality metrics in transients are provided, such as settling time and dynamical quality. Case study at a factory is given to demonstrate the derived approach. The conclusions drawn illustrate the applicability of transient quality evaluation of multi-stage systems.
A Health Status Assessment Approach of Intelligent Manufacturing System based on Fuzzy Analytic Hierarchy Process
Authors: Kang Yu-Yun , Feng Gui-Fang , Sun Jie 
Published: May 2020

Abstract
In order to timely identify, analyze the health status of an intelligent manufacturing system, an approach based on fuzzy analytic hierarchy process (FAHP) is proposed. In the method, the random perturbation is divided into several classes and each is subdivided to several events. Then an evaluation model is constructed and it has two-layer criteria system, which can evaluate every perturbation class and the whole system at the same time. The monitoring data is expressed with 10 scales and the evaluation accuracy is more improved. FAHP is used to calculate the criteria weights. Finally, the proposed method is detailed illustrated by an example, and the method is verified.
Motion Analysis-based Design of Wall Painting Tool Storage
Authors: Ruoyue Tang , Luwei Chen , Jingya Wang 
Published: May 2020

Abstract
While the wall painting is applied frequently in interior design and decoration, many problems exist in the wall painting tools usage and transportation. With the interview method conducted in the investigation of the wall painters, based on the motion analysis and the economic principle of the related action, the design prototype of the wall painting tool storage was proposed. Conducting the multiple actual working scenes motion test, this design was continuously improved aiming to offer an ergonomic optimization with the appearance and function balanced design.
Design of Pre-stressed Cable Rod Radar Array Structure Based on Finite Element Analysis
Authors: Wang Jin Wei , BaoFu Tang , Cai JianGuo , Jiang HongHu 
Published: May 2020

Abstract
In recent years, with the increasingly high requirements of radar thinness, the radar array appears thinner and thinner, which is easy to make the stiffness of the radar array is not enough, leading to serious deformation of the radar array, and thus affecting the work of the radar and the whole machine life. As a new type of space structure with light weight and high strength, the pre-stressed cable-stayed structure can play a good role in replacing the traditional front structure. According to the overall design requirements of a radar and the RMSE requirements for the plane flatness, the pre-stressed cable-stayed structure of the radar array is preliminarily designed, and the finite element analysis results are used to optimize the design and finally meet the design requirements.
Titanium Coatings Plasma Sprayed with/without a Shroud
Authors: Zhou Hong , Peng Cheng , Liu Zhi , Al-Rawi Mohammad , Kanna Jai 
Published: May 2020

Abstract
Titanium coatings were deposited by plasma spraying with and without a shroud. The as-sprayed titanium coatings were then microstructurally examined. A comparison in microstructure between titanium coatings with and without the shroud was carried out. Based on the analytical results, it showed that the shroud played a critical role in protecting the titanium particles from oxidation. The presence of the shroud in the plasma spraying brought about a better heating of the particles in the plasma jet due to a mitigation of air entrainment with the shroud, thus a reduction in coating porosity was obtained. An enhanced microstructure in the shrouded titanium coatings were observed compared to the air plasma sprayed counterpart.
A New Method to Identify the Diesel Engine Modal Parameters based on Self-Excitation
Authors: Hou Biao , Liu Xing , chen Jiheng , Liu Feng , Tian Ye , Tan Jingsong 
Published: May 2020

Abstract
At present, the methods to study the dynamic characteristics of diesel engine structure include finite element analysis method and experimental analysis method. Among, 60% of the structural stiffness and 90% of the damping ratio of the whole diesel engine come from the joint part, and the dynamic characteristics of the joint part of the diesel engine are very complex, so it is difficult to establish an accurate finite element model, and the results of finite element analysis methods are often not accurate. For the experimental analysis method, it is mainly divided into the traditional Experimental Modal Analysis method (EMA) and the Operational Modal Analysis (OMA). The EMA it alays needs to measure the excitation force of the diesel engine and the vibration response of the structure, simultaneously. And the influence of motion factors on the structure dynamics cannot be considered. The structure is excitated by the working environment, and only analyzes the modal parameters of the structure with the vibration response. Few scholars analyze the OMA for diesel engines. This paper proposes a new method to identify the modal parameters of diesel engine based on dry run. In this paper, the design and research of the motion law of the air-running self-excitation is carried out, and the validity of the method is verified.
Based on Vibration Signal to Identify the Diesel Engine Modal Parameters under Working Condition
Authors: Liu Xing , chen Jiheng , Hou Biao , Tian Ye , Liu Feng , Tan Jingsong 
Published: May 2020

Abstract
The methods to study the dynamic characteristics of diesel engine structure include finite element analysis method and experimental analysis method. It is difficult to establish an accurate finite element model, since the results of finite element analysis methods are often not accurate. For the experimental analysis method, it is mainly divided into the traditional Experimental Modal Analysis (EMA) and the Operational Modal Analysis (OMA). The EMA method always needs to measure the excitation force of the diesel engine and the vibration response of the structure simultaneously. And the influence of motion factors on the structure dynamics cannot be considered. The structure is excitated by the working environment, and only analyzes the modal parameters of the structure with the vibration response. Few scholars analyze the OMA for diesel engines. This paper proposes a new method to identify the modal parameters of diesel engine based on self-excitation. In this paper, the theory of self-excitation mode parameter identification is demonstrated by derivation, and the validity of the method is verified.
Importance Measure Analysis Method for Maintenance based on Mutil-Function Testability States
Authors: Cao Zhiyuan , Dong Haiyong , Gu Qingfan , Wang Guoqing 
Published: May 2020

Abstract
Maintenance order plays an important role in industrial field, which influences multiple factors such as costs. Current method is based on importance measure using the fault tree analysis. Simply based on the fault tree of the failure condition, such method ignore some vital information hidden in other testability states, and may results in unsuitable maintenance order. This paper puts forward a novel method to evaluate importance measure based on multi-function testability states, which can be used to optimize the maintenance order. To illustrate the utility of this method, the article uses a vehicle model, and compares the different results to validate the effect of the proposed importance measure. This method can be utilized to evaluate the maintenance order containing multiple functions.
Neural Network Based Modelling and Steering Control of an Intelligent Vehicle Under Dynamic Sensitive Conditions
Authors: Zhang K , Wang S J , Ji L , Wang C 
Published: May 2020

Abstract
A neural network based modelling and steering control method of an intelligent vehicle under dynamic sensitive conditions is proposed in this paper. Four radius function neural networks are used to compensate the modelling error of a traditional dynamic vehicle steering model. The designed control law is consisted of four terms: a neural network term, a proportion term, an integral term and a robust term. Stability is analysed through Lyapunov function and the training law is generated at the same time. Test results show that the designed steering controller works quite well and is of great value in path tracking of an intelligent vehicle when the vehicle dynamics getting significant.
Adaptive Sliding Mode Control of Artillery Coordinator Based on Disturbance Observer
Authors: Gan Jinjie , Chen Longmiao 
Published: May 2020

Abstract
In order to improve the control accuracy of the artillery coordinator composed of hydraulic servo system under various uncertain conditions such as extreme environment, unknown disturbances, and system parameter changes, an adaptive sliding mode control strategy based on disturbance observer is designed. Sliding mode control can make the system follow the designed sliding mode dynamic surface state trajectory, and realize the control of non-linear system. Increasing adaptive control can prevent system failure due to excessive sliding mode switching gain. Based on this, disturbance observers are added, feed-forward compensation is performed, and the influence of system parameters and load torque changes on the system is reduced to reduce chattering and effectively improve control performance. The electro-hydraulic joint simulations show that the algorithm can make the system meet the control requirements under complex working conditions under different coordination angles, ammunition and no-load conditions.
Punching Shear Strength of Reinforced Concrete Flat Slabs with Macro Synthetic Fibers
Authors: Nassif Nadia , Altoubat Salah , Maalej Mohamed , Estephane Pierre 
Published: May 2020

Abstract
Discrete macro fibers such as steel and synthetic have been recognized as an attractive material to improve concrete properties such as flexural toughness, shear strength, impact characteristics, deflection capacity and concrete ductility. In this paper, the effect of macro synthetic fibers on punching shear resistance and cracking behaviour of reinforced concrete slabs was investigated. A total of six reinforced concrete slabs were designed, instrumented and tested in displacement control mode, under monotonic center-point load in simply supported configuration. Synthetic fibers were added to the concrete slabs at dosage rates of 0.5% and 1% by volume. The results have shown a significant increase of the punching shear strength, energy absorption capacity and ductility of the slabs. The addition of 0.5% and 1% of macro synthetic fiber to the slab increased punching shear strength by 30% and 70% and increased energy absorbance by 40% and 80%, respectively.
Search for the maximal threshold Co content for the oxidation behaviour point of view for 25wt.%Cr-containing TaC-strengthened cast superalloys designed for use at 1200°C on long time
Authors: Berthod P , Gomis J P 
Published: May 2020

Abstract
The base of chromia-forming cast superalloys is the most often constituted of nickel and/or cobalt. Both elements may be simultaneously present, for instance Co for promoting good mechanical properties and Ni for stabilizing the austenitic matrix and favouring good ductility and machinability. In service, superalloys must also resist hot oxidation, property favoured by Ni but disadvantaged by Co. In (Ta,C)-rich cast superalloys exposed at high temperature, the intergranular strength may be enhanced by the very efficient TaC carbides while the higher the Co content the stronger the matrix creep resistance. In this work, six alloys designed to be chromia-forming and TaC-strengthened were exposed to laboratory air at 1200°C for 170 hours, to examine how the deterioration by oxidation and the evolution with time of the strengthening carbides in the bulk may be influenced by the Co/Ni ratio in the case of this important family of superalloys. The characterization of the formed oxide scales and of the morphologic evolution of the carbides allowed identifying a {0.6Co-0.4Ni}-proportion for the base elements. Such combination obviously allows keeping a chromia-forming behaviour and a good adherence of the protective oxide scale on the alloy, as well as a good resistance of the TaC against fragmentation.
Modeling and simulation of a gauge shaped beam coupled with macro fiber composite for energy harvesting application
Authors: Ibrahim D S , Sun B B , Sharif U , Oluseyi O A 
Published: May 2020

Abstract
This paper presents a novel unimorph piezoelectric cantilever with non-conventional geometry named as gauge shaped beam to investigate stress, Eigen frequencies and electric potential for improved vibration energy scavenging. The harvester is made of macro fiber composite (MFC) as the active piezoelectric layer bonded to a brass substrate. Complete transversely isotropic elastic and piezoelectric properties are assigned to the composite structure in a three-dimensional finite element model using COMSOL Multiphysics. Dynamic behaviour of the proposed structure was simulated and the results obtained were compared with traditional rectangular geometry. The results proved that the gauge shaped beam has a higher stress distribution around the gauge length, enhanced electric potential and lower resonance frequencies than the conventional rectangular structure which makes it better for the design of piezoelectric based vibration energy harvesters.
Relations between microstructure and hardness of plain carbon steels using eddy current technique
Authors: Costa Isadora M. O. A. , Mesplont Christophe , Bouquerel Jérémie , Vogt Jean-Bernard 
Published: May 2020

Abstract
Heat-treatments were carried out on carbon steels ranging from 0.03 to 0.78 wt%C, in order to produce various ferrite-pearlite microstructures. The specimens were characterized by metallographic examinations and microhardness measurements. A clear dependence was found between microstructure characteristics and eddy current outputs measured by means of an electromagnetic sensor: resistance was observed to increase, while inductive reactance decreased in the order of pearlite and ferrite microstructures, and with decreasing interlamellar spacing of pearlite. These components are related to the electrical resistivity and magnetic permeability of the steels. The potentiality of this technique was highlighted for monitoring phase proportions, quantitatively assessing pearlite interlamellar spacing, giving also information about mechanical properties, such as hardness. It reveals the great potential of eddy current testing as a reliable non-destructive tool for metallurgical and mechanical characterization of carbon steels.