bluuebunny/crossref_metadata_2025_split huggingface dataset:
Non-vacuum electron-beam surfacing of coatings with the ultrafine structure
Authors: Poletika I M , Perovskaya M V 
Published: November 2019

Abstract
The paper employs an ELV-6 accelerator to surface low-carbon steel with a tungsten carbide powder thus obtaining steel coatings with high hardness but low wear resistance. The abrasive wear resistance is considerably increased by changing the composition of the surfacing mixture due to the introduction of nickel as an austenite stabilizer and titanium carbide as a modifier. Besides, the paper deals with surfacing with a powder mixture of chromium carbide, chromium, and titanium carbide to produce bifunctional coatings with both high wear and corrosion resistance, which is explained by the presence of chromium in the layer. The methods of physical metallurgy are used to study mechanisms responsible for property changes. A substantial increase in wear resistance is shown to be related to the ductile austenitic structure formed in the deposited layer matrix when nickel is introduced and to rapid structure refinement in the presence of multiple centers of crystallization represented by dispersed precipitates of TiC.
Hybrid method of controlling arc welding process with consumable electrode and related processes
Authors: Sidoruk V S , Maksimov S Yu , Krazhanovsky D N , Saraev Y N 
Published: November 2019

Abstract
For the development of a classical method of mechanized arc welding with a self- regulation of the process of melting the electrode supplied to the welding zone at a constant speed, the following combination was proposed: on the one hand, a digital power source with automatic control and programming of volt-ampere characteristics VAC, which is a two-step one in our case: a – for increased arc length (with a low current), b – for shortened arc (with a high current); on the other hand, self-regulation of the melting process by the corresponding reaction of the power source. Moreover, the electrode melting occurs in a programmed oscillatory mode between the extreme values of the arc length: maximum and minimum. Such a combination is called a hybrid method of controlling the process of arc welding with a consumable electrode.
Modeling of laser welding of plates made of dissimilar metals with the use of a composite insert
Authors: Shapeev V P , Cherepanov A N , Isaev V I 
Published: November 2019

Abstract
This paper deals with computer simulations of laser welding of plates made of dissimilar metals using a composite intermediate insert. They are performed with the previously developed 3D numerical model implemented with the collocations and least squares method. The use of the composite insert when welding dissimilar alloys prevents the formation of brittle intermetallic phases that adversely affect the strength of the joint. Based on the proposed mathematical model, the features of butt-welding of titanium and stainless steel plates and aluminum and titanium plates are investigated. The rational thermal conditions of laser welding and the geometric parameters of the welds are determined.
An analysis of vehicle - railway exchanger interaction
Authors: Tudorache M C , Neagoe I 
Published: November 2019

Abstract
The fast variation of the section and contact characteristics of railway exchangers is a difficult matter for an analytical approach. At the same time, vehicle - railway exchanger system includes multiple contact patches, discontinuities in the contact points evolution and the necessity to compute stresses and deformations. As a consequence of the harrs working conditions in the system there is a permanent concern to improve its performance. The analysis of the state of art in the research indicated the need of a complex theory for the study of the mechanical contact. In the paper, a tridimensional analysis of the vehicle - railway exchanger contact patch is carried out using “Contact” software, based on Kalker’s theory. The outcome of the study is the computation of tangential forces, creepage speeds and stresses distribution in the contact patches, in order to elucidate the vehicle evolution during this interaction and the estimation of the running safety.
The vibration behaviour of a freight wagon in the presence of irregularities of the track
Authors: Mazilu T , Dinu V M 
Published: November 2019

Abstract
The paper presents an analysis of the behaviour of the vertical vibration of a freight wagon featured with dry friction dampers in suspension. To this end, the wagon model is reduced to an oscillator with two degrees of freedom corresponding to the suspended mass of the wagon and the wheel. The suspension has progressive characteristic in two steps according to the empty/loaded state. Coulomb’s model is considered to model the dry friction damper. The vibration is induced by the track irregularity which is synthetized from an analytic spectrum. Vibration behaviour exhibits two different aspects: at low speed, the suspension is locked, and at high speed, the stick-slip vibration occurs. Acceleration of the suspended mass of the wagon and wheel-rail contact force increase along the speed. Wagon loaded state influences the wheel-rail contact force, but it has no impact upon the acceleration.
Use of the Ishikawa diagram in the investigation of some industrial processes
Authors: Botezatu C , Condrea I , Oroian B , Hriţuc A , Eţcu M , Slătineanu L 
Published: November 2019

Abstract
The use of the Ishikawa diagram was proposed by Japanese professor Kaoru Ishikawa in the 1960s. The diagram must highlight the possible causes of a certain effect. In the research presented in this paper, the analysis method based on the design of the Ishikawa diagram was used to identify the factors able to ensure the adequate development of some investigations concerning certain industrial processes. It was found that various criteria could be used to evaluate the effect. Versions of Ishikawa diagrams were proposed in the cases of chemical engraving process, cast iron milling process, 3D printing process and the reliability of computer subsystems, respectively. A comparison of the Ishikawa diagram method with the systemic analysis method highlighted some particular aspects that could be considered when the problem of investigating the influence of certain process input factors on the process output parameters is formulated.
Aluminum based metastable alloys for additive manufacturing
Authors: Nitoi A , Cristea D , Pop M A , Bedo T , Varga B , Munteanu D 
Published: November 2019

Abstract
Additive manufacturing (AM) is a technology which has the potential to replace conventional casting methods. Its capacity to obtain complex shapes is the main advantage over other manufacturing techniques. Metastable structures in the form of supersaturated or amorphous/nano solid solutions could potentially help the manufacturing process, due to energy release during heating, caused by the phase transformations towards stable structures. Aluminum-based alloys are of interest due to their combined high specific strength to weight ratio, good ductility and superior corrosion resistance. The paper presents results concerning the development of Al-Si-Ni alloys in bulk and melt-spun ribbon forms. The thermal stability of the aluminum-based alloys was analyzed by Differential Scanning Calorimetry, while some of the mechanical properties were assessed by instrumented indentation. The fast-cooled alloys exhibit metastable structures, inferred from the exothermal peaks observed during heating. A hardening phenomenon was also observed in case of the melt-spun ribbons, compared to the bulk alloys.
Assessing the influence of significative parameters used in 3D Fused Filament Deposition
Authors: Pisarciuc C 
Published: November 2019

Abstract
The present article presents an analysis of the several parameters used at Fused Filament Deposition-FFD 3D printing process. To evaluate these parameters, a laptop / tablet support has been chosen as a subject that presents different characteristics both from the point of view of mechanical demands, to which it is subject, as well as geometry. The reason for choosing such an object to be produced by additive technology is the fact that in its geometry are encountered most of the spatial surfaces that present difficulties to be obtained by this method. In this context, the article highlights the steps that are necessary to get 3D printed objects to meet the initial design requirements. For the assessment of the degree of influence, parameters were identified and then they were evaluated to find an optimal solution. In the conclusions are presented some useful values for practical applications of this type and some considerations about two types of 3D slicers.
Experimental researches concerning the manufacture of multitool 3D printer, type DIY (do it yourself)
Authors: Baila D I , Tonoiu S , Ştefan M C , Sapadin I 
Published: November 2019

Abstract
In the last decade, additive manufacturing has greatly developed and the manufacture of cheaper 3D hybrid (multitool) printers has increased. Hybrid 3D printers are equipped with interchangeable heads for manufacture and permit multiple types of processing such as 3D printing, CNC cutting, laser engraving or deposition of pasty materials. The objective of this paper was to manufacture a hybrid 3D printer prototype, type DIY (do it yourself) and was equipped with g-code software necessary for 3D printing process and for CNC cutting. The materials used for construction for this hybrid 3D printer are cheap and accessible and some of electronic components are reused and recovered from old equipment and the functional 3D hybrid printer obtained can be a model for sustainability of products.
Process planning solution for increasing the productivity and robustness of work schedules for batch production processes
Authors: Catana M G , Dijmărescu M R , Tunsoiu N 
Published: November 2019

Abstract
This paper analyses the issue of ensuring enhanced productivity and robustness to work schedules designed for multi-operational batch production processes, when a fixed, limited number of workstations can be used for production. The productivity of a batch production schedule for a specific quantity of items is measured by the length of its cycle time, while the robustness of the schedule is given by the size and distribution of operational slack times that are ensured during the production process run. It is mathematically demonstrated that a simple process planning solution may be the key for meeting the above mentioned objectives, if it is possible to be applied in practice in combination with the lot streaming strategy for the production flow.
Development of key performance indicators modules for small and medium-sized enterprises in production industry
Authors: Tieber A , Manolache D S , Gheorghe M 
Published: November 2019

Abstract
For small or medium-sized companies in the production industry, it is strongly advisable to intensify the use of key indicators in analysis and daily work, as well as open and honest communication throughout all levels of the organization as key factors for success. Although many enterprises now run customer relationship management systems to promote professionalization in the areas of customer satisfaction and customer service, key indicator systems are rarely used in a meaningful and optimal way. Massive potential for optimisation can be found in the whole system, so that a scientific survey study has been carried out in a number of companies from production industry. Based on the elements revealed by this study, a development of key performance indicators modules is proposed and synthetically described in the present paper. This development includes a series of key performance indicator – modules covering process and production management, sales management, customer and acquisition, human resources and innovation management, as an advanced structuring system in the field of key performance indicators.
On Orbit Capture and Control of Space Manipulator Based on Magneto Rheological
Authors: Wang Chao , Wang Jianwei , Fang Dong , Li Donglin , Zhang Ying , Kong Dalin 
Published: November 2019

Abstract
With the rapid development of space technology, the performance and technology of spacecraft is in the continuous improvement. The key technology for the non-cooperative target satellite on-orbit capture and control becomes very important. For the question of on orbit capturing a non-cooperative target, a method based on Magneto Rheological (MR) damper is proposed. There are many successful applications of MR damper in ground-base and aviation systems. However, the application of this device on a space manipulator has not been addressed yet. In this paper, A 6DOFs space robot is built in Maplesim, and analyses the kinematic and dynamic model, and the component of MR damper is also created, after simulation, the results shows that the angular velocities of joints and base has been smoothly dampen. Although the control algorithm is simple, it’s very valuable to use the MR damper in capture non-cooperative target.
Magnetic Simulator Testbed for APSCO Student Small Satellite Project
Authors: Uscategui J , Xinsheng W 
Published: November 2019

Abstract
The Student Small Satellite (SSS) is a university project of Asia-Pacific Space Cooperation Organization (APSCO), composed by one microsatellite (SSS-1) and two 3U CubeSats (SSS-2A and SSS-2B). Regarding SSS-1 and SSS-2A satellites, the active 3-axis magnetic control strategy has been applied in the Attitude Determination and Control System (ADCS). In this paper, the necessary study for the development of a Magnetic Simulator Testbed for the SSS-1 and SSS-2A satellites was performed using one pairs of Helmholtz coils for each axis of rotation (X, Y, Z). Each pair of coil can generate a sufficiently large and stable magnetic field that simulate the Earth’s magnetic field but with a reliable level of accuracy, to perform the ADCS test on the satellites. Matlab software was used to generate the propagation of the orbit for the satellites, to calculate the Earth’s magnetic field around that orbit and simulate a pair of Helmholtz coil in each axis of rotation to reproduce the Earth’s magnetic field using the Biot-Savart Law. The results obtained for propagation of the orbit, calculation of terrestrial magnetic field and reproduction of the magnetic field through the Magnetic Simulator Testbed, were very close to the results obtained in important researches previously consulted, giving reliability to this research and allowing an analysis to determine the real physical size that Magnetic Testbed should have. The size determined, is very close to what was expected, allowing to conclude the reliability and viability of the development of the Magnetic Testbed for APSCO SSS Project.
A Design Method for Twist Distribution along Wing Span
Authors: Liu Xiaoyan , Cheng Pan , Zhao Yang 
Published: November 2019

Abstract
A design method for wing jig shape twist is proposed. Target cruising aerodynamic loads are applied to structure model, and the deformation converge gradually using predictor-correction displacement iterative method. When ensuring the relative twist distribution in the streamwise section, a wing jig shape with straight leading ledge is created, then an aeroelastic coupling iteration is started to achieve the deformed elastic cruising shape. Taking a large aspect ratio swept wing as an example, analysis results show that the deformed elastic cruising wing had an identical streamwise twist distribution compared with rigid designed cruising shape. Sectional lift distribution along with pressure distribution matches well with that of the designed cruising shape, and the drag gap among them is not significant. There might be some change in shock wave chord position between elastic cruising wing and designed cruising wing for outboard wing section. By slight adjusting twist with unchanged airfoil profile, the difference above could be improved.
Adaptive Refinement based Integral Method for Load Transfer in Fluid/Structure Interaction Problems
Authors: Cheng Pan , Ding Zekai , Zhang Wu 
Published: November 2019

Abstract
In fluid-structure interaction simulations using a partitioned approach, especially aeroelastic analysis, each physics component solves on its own mesh, and the interface between these meshes are in general non-matching. Force and displacement must be transferred from one mesh to another. Generally speaking, two classes of methods have been developed and applied in engineering: point wise interpolation and mapping method. For practical problems, point wise interpolation is not good enough in conversation and mapping method requires detailed meshes to describe surfaces of both fluid side and structure side. This paper presents a flexible, conservative and robust method which only requires surface mesh on fluid side. The merits of new method in terms of conversation properties were discussed. Also, the numerical results of practical problems are demonstrated in this paper.
Study on Linear and Nonlinear Coupling Damage Model of BGA Solder Joint
Authors: Lei Dongyang , Sun Yufeng , Qi Chaojie , Hu Weiwei 
Published: November 2019

Abstract
Due to the complex and changeable environment in space, the ball grid array (BGA) has become one of the most important form of the electronic package in aerospace industry. As the main factors which affect the reliability of electronic products, temperature and vibration will lead to creep and fatigue respectively. Based on the damage mechanism, taking SnAgCu solder joints as the research object, the relationship between the resistance and the damage index are established by using the micro-conductive model of resistance. The mathematical model between stress cycle and damage value is established by damage mechanics. Then, the linear and nonlinear interaction models are established to simulate the initial and mature damage of solder joints respectively based on the principle of area interference. Finally, Monte Carlo method is used to simulate the growth of the crack, concluding that it’s suitable for the linear model when the damage index is less than 0.155 and the nonlinear model is suitable when the damage index is more than 0.155.
Deep Learning for Aircraft Wake Vortex Identification
Authors: Weijun Pan , Yingjie Duan , Qiang Zhang , Jiahao Tang , Jun Zhou 
Published: November 2019

Abstract
Aircraft wake vortex refers to a pair of closed vortices due to the air pressure difference between the upper and lower surfaces of the wing when the aircraft is flying. During the take-off and landing of the aircraft, the wake vortex of the preceding aircraft threatened the safety of the aircraft following its approach. Especially in the near-field phase, due to the low altitude of the aircraft, the wake vortex is more harmful under the influence of the ground effect. Therefore, the wake vortex of the front aircraft can not be ignored. In order to maintain air traffic safety and accelerate the smooth flow of air traffic, this paper used a YOLO v3 model based on the principle of deep learning to identify the wake vortex generated by the aircraft. Through laser radar scanning, data processing, and deep neural network simulation experiments, the results show that the model can achieve high confidence recognition of the aircraft wake vortex, and can provide air traffic controllers with auxiliary decision information in actual work to ensure aircraft safety.
Study on the Effect of Excitation Circuit of Spectral Lamp on the Temperature Coefficient of Physics Package of Rubidium Atomic Clock
Authors: Guo Yonggang , Zhang Jun , Wang Shiwei , Wang Jianxiang , Zhu Lili , Tu Jianhui , Liu Zhidong 
Published: November 2019

Abstract
As one of the important factors affecting the long-term frequency stability of Rubidium atomic frequency standards (RAFS), the temperature coefficient has a great influence on the performance of RAFS. The temperature coefficient of physics package has an important influence on the temperature coefficient of rubidium atomic clock. The instability of temperature is often the most important error term of RAFS. The variation of temperature to several degrees means a month’s aging. As an important part of rubidium atomic clock physics package, the Lamp Excitation Circuit directly affects the voltage adaptation area and temperature coefficient of Rubidium gas cell physics package. In order to satisfy the long-term frequency stability and adapt extraterrestrial environment, we propose the improvements of Lamp Excitation Circuit in physics package of Rubidium Atomic Clock, since minute current change of Lamp Excitation Circuit are mapped onto the clock’s long-term frequency stability, and the stabilization of the lamp excitation circuit has the potential to significantly improve the RAFS’ long-term frequency stability and temperature coefficient. We demonstrate that the temperature coefficient of physics package can be reduced obviously by improved Lamp Excitation Circuit. Suggesting that performance of the RAFS could be improved greatly further.
Conceptual Multidisciplinary Design Optimization of Commercial Aero-engine System
Authors: Guo Fushui , Zhao Shiqi , Zhou Xiaodong , Fan Jun , Mi Dong 
Published: November 2019

Abstract
Commercial aero-engine design is a complicated task, which involves many disciplines, such as thermodynamics, aerodynamics, solid mechanics, heat transfer and materials science. Besides, for the sake of market requirements, designing a commercial aero-engine should not only consider the performance, fuel consumption, thrust and weight, but also pay special attention to noise, emissions and other environmental indices. In order to balance conflicts among various discipline indicators, and design an aero-engine with high comprehensive performance, we apply the multidisciplinary design optimization (MDO) technology to the conceptual design of an aero-engine system in this paper. Particularly, the system conceptual design of a high-bypass-ratio turbofan aero-engine is selected as a case study. A total of five disciplines, including thermal cycle, aerodynamics, structural mechanics, emission and noise, are considered. Meanwhile, six modules are integrated and analysed carefully. These modules include performance evaluation at the design point, performance evaluation at fifteen different off-design points, engine size assessment, engine weight assessment, engine emission assessment as well as engine noise assessment. On the basis of these modules, a MDO platform is set up. In addition, one optimization study with a single target of fuel burn is carried out by utilizing the adaptive simulated annealing (ASA) algorithm. Moreover, another optimization with multiple targets of fuel burn as well as nitrogen oxide emission is also studied by employing the non-dominated sorting genetic (NSGA-II) algorithm. The results shows that the MDO method for the commercial aero-engine can obtain better solutions for the system by fully taking into account the mutual effects among different disciplines.
A Transmission System Planning Method Considering Demand-side Response and Capability for Accommodating Wind Power
Authors: Sun Bo , Zou Bo , Yan Jubin , Wang Xiaoming , Yang Yuxuan , Huang Yan 
Published: November 2019

Abstract
The large-scale development of grid-connected wind power, which is intermittent, random and uncontrollable, has introduced great challenges to power system planning and operation. Power system planning should fully consider the capability for accommodating wind power, as well as system’s regulation capability and spare capacity. Given this background, a bi-level transmission system planning model for this purpose is proposed in this paper. In the proposed model, demand-side response resources, such as incentive load and interruptible load, are used for peak-load shifting so as to optimize power flow distribution, reduce transmission investment and improve the utilizaiton level of wind power. The two levels are implemented interactively and iteratively, and finally converge to an optimized planning scheme considering both security and economy. The essential features of the developed model and adopted algorithms are demonstrated by a modified 18-bus test system.