bluuebunny/crossref_metadata_2025_split huggingface dataset:
Experimental validation of CFD model with the air velocity and temperature in the plant factory
Authors: Zhou Shenghan , Zhang Xin , He Zhongqun , Liu Huan , Liu Ke , Chen Yufei , Peng Fei , Yang Qichang , Zheng Yangxia , Lu Wei 
Published: August 2020

Abstract
A computational fluid dynamics (CFD) model for the closed plant factory has been developed in this study, the experimental validation of CFD model with the air velocity value was compared with the measured air temperature value. The results showed that the mean relative error of validation with the air velocity was 15%, and comparable with experimentally observed air temperature profile inside the plant factory with RMSE of 3% which shows the utility of CFD to study plant factory microclimatic parameters.
The modified cyclic multi-surface plastic model of sandy soil based on damping ratio
Authors: Zhang Yan , Sun Shulin , Qin You 
Published: August 2020

Abstract
Traditional multi-surface plastic model always overestimates the accumulated plastic strain when it is applied into sandy soil under cyclic loading. Considering this overestimation can be reflected through equivalent damping ratio of the hysteretic loop and the damping ratio can also include the real anisotropic plastic hardening which is simply considered in kinematic hardening rule and isotropic hardening rule, series of strain-controlled cyclic simple shear tests were conducted to obtain the relationship between correction coefficient of hardening rule and initial state including initial effective, then a modified cyclic multi-surface plastic model was established by regarding the subsequent hysteretic loop as the new first loop with a new initial state which is the state at the start of the fourth quarter of the previous loop, thus, the plastic hardening formula can be upgraded in the process of loading.
Xiakou Xiangxi River Bridge structure design
Authors: Zongrun Rao , Ming Li , Zhuoqun Chen 
Published: August 2020

Abstract
Xiakou Xiangxi River Bridge is located in the upstream of the Three Gorges reservoir area. It is a (90+238) m single tower, Leaning Tower central cable surface mixed beam cable-stayed bridge. Its main span adopts a cross the river to meet navigation and flood control needs. The main concrete beam and the steel box girder of the main span are of large-angle inclined web box section with cantilever flange. The steel and mixed surface is at 11.05m across the bridge tower. The full width of the bridge deck is 25.5m. This bridge adopts the oblique “pipa” shaped main tower, the height of the main tower is 126m, composed of the upper tower column, the lower tower column, diaphragm and so on. The tower body deviates from the vertical surface of the bridge by 10° and leans towards the bank side. The foundation of the main tower is an integral pile foundation of the pile bearing platform. 2×17×2 high-strength parallel steel wire stay cables are used to arrange the fan-shaped space cable surface.
Optimization of the construction sequence of the expanding excavation around Tunnel
Authors: Wang Yu-Feng , Wu Li , Sun Miao , Ma Chen-Yang , Yuan Qing 
Published: August 2020

Abstract
With the background of the construction of the Loushan Tunnel, Flac3D software was used to simulate three different expanding excavation sequence schemes. The simulation results were compared and selected, and it determined that Scheme3 is the best scheme. In the construction site, tunnel vault settlement and hance convergence were measured and compared with the simulation results. Conclusions are as follows: ①The final vertical displacement of Scheme.1 was greater than that of Scheme.2 and Scheme.3. In scheme 2, the horizontal displacement of the middle-upper part of the tunnel increased sharply after the excavation of the upper-right part. The maximum bending moment of the supporting structure of Scheme.3 was smaller than that of the other two schemes. In addition, the maximum bending moment in the whole process of expanding excavation transited smoothly, and it fluctuated the most in Scheme.2; ②When the upper-left part is expanded, the vertical displacement and bending moment of the supporting structure of the three schemes all increase greatly. In the actual construction, the most unfavorable factor is that the settlement detection value of the vault increases rapidly after the expanding excavation of the upper-left part; ③The construction sequence adopts Scheme.3, the settlement value & convergence value becomes more and more stable about 7 after excavation, the accumulated settlement value is 17.146mm, and the accumulated convergence value is 14.512mm. The field data is close to the simulated data, no accidents occur in the construction process, and no abnormal phenomena are found in the monitoring and measurement process.
Back analysis of permeability coefficient of earth-rock dam based on EMD-RVM
Authors: Chen Yi 
Published: August 2020

Abstract
Since contemporary information-retrieval systems rely heavily on the content of titles and abstracts to identify relevant articles in literature searches, great care should be taken in constructing both. Since the permeability coefficient of the dam material of the earth-rock dam directly affects the seepage flow of the dam, in order to improve the accuracy of retrieving the permeability coefficient from the measured value of the seepage flow, the empirical mode decomposition method (EMD) is used to monitor the actual seepage flow of the weir. After decomposition, multiple sets of intrinsic modal functions (IMF) were generated to fit the relationship between water level and seepage flow; then the finite element software was used to calculate the seepage flow corresponding to the randomly distributed infiltration parameters at different water levels in order to the RVM model performs inverse analysis on the permeability coefficient. The training sample group is constructed by finite element calculation, the calculated seepage volume of the sample group is used as the input value, and the corresponding permeability coefficient is used as the output value. Based on EMD-RVM, a nonlinear mapping relationship between the permeability coefficient and seepage volume of each section of the face rockfill dam is established. Using the model inversion, the results show that the EMD-RVM model has high inversion accuracy and is significantly higher than the conventional RVM model and GA-BP model. The infiltration pressure of the face rockfill dam can be calculated from the inversion result of the permeability coefficient, and the error with the measured value is small, which verifies the feasibility of the model.
Examination of welded joint of titanium alloy used in oral surgery
Authors: Kónya J , Kulcsár K , Hargitai H 
Published: August 2020

Abstract
The additive manufacturing of customized Ti-6Al-4V (Grade 23) implants, which in the present research concerns the dental and maxillofacial surgical field, may require complex manufacturing technology due to their complexity and assembly. In practice, additively manufactured titanium implant elements are supplemented by threaded sleeves that allow disassembly. These turned elements made from Grade 5 material quality rolled preform are joined by laser micro-welding with Grade 1 material. This special process for implant production is still not widespread in current manufacturing practice, and there is no technical recommendation for the manufacturing parameters of these implants. The aim of our research is to explore the possibilities and limitations of additive process in the manufacture of custom-made implants and to provide guidelines for optimal manufacturing and welding parameters. In the initial phase of the research, preliminary experiments were conducted with the conventional and additive manufacturing of cylindrical test specimens and with the production of combined products by micro-welding. The specimens were subjected to tensile testing, the weld was examined by CT, and the fracture surfaces were studied by optical microscope and scanning electron microscope.
Enhancing the Firework Algorithm ecosystem for the reconstruction of the HTC function
Authors: Fried Z , Felde I , Szénási S 
Published: August 2020

Abstract
The heat transfer coefficients reconstruction could be solved using several ways and configurations. The Inverse Heat Transfer Problems (IHCP) collects all kind of algorithms which try to solve the Heat Transfer Problems. These algorithms try to calculate the heat transfer coefficients inversely. There is some solution for solving this numerical method, but the bio-inspired solutions are better here even though they have some limitations because of this is a kind of genetic one. Using the Fireworks Algorithm (FWA), it is possible to introduce new methods, and modify the original FWA controlling system and parameters in an easy to adapt to this problem. Extensions are suggested with the major limitation of the genetic methods which solved by the proposed one, and with the faster computation of the new modified method.
Development of high power femtosecond laser microstructures on automotive stainless steel
Authors: Tajti Ferenc , Berczeli Miklós 
Published: August 2020

Abstract
It is indispensable for the industry to introduce the most accurate manufacturing technologies. Therefore, laser beam machining centres have been gaining popularity in machining equipment over the last few years. We can perform quick and highly accurate machining with the latest generation of laser equipment which operates in femtosecond pulse mode. The purpose of this study is to find the best femtosecond laser surface machining technique on stainless steels by changing technological parameters. We have compiled a general table that lists the parameters, with variable values in bands and columns to select the most accurate surface treatment with minimal heat affected zone.
Optimization of material removal parameters by femtosecond laser pulses
Authors: Berczeli Miklós , Tajti Ferenc 
Published: August 2020

Abstract
Lasers are widely used and have become indispensable in many areas. Their application is very advantageous in many cases, the technology is very fast and high-precision machining can be achieved. Lasers are increasingly used in the automotive, aerospace, electronics, and medical industries. With this technology, we can perform almost any kind of material processing whether drilling, cutting, welding or even heat treatment. The laser can be well integrated into various machining systems and well automated. With the advancement of technology, we are capable of producing femtosecond pulsed lasers which machines are capable of high peak performance. Because of the high peak power and short pulses, other physical phenomena occur when the laser interacts with the material, so the method of material removal is different from longer laser impulses. Their application is expected to provide a much more controlled, more precise material removal, with very good surface quality, free of burrs and other dirt and deposits. One of the most important benefits expected from the use of technology is the minimal or no heat affected zone. In our research we are looking for a parameter that can achieve the most accurate material removal with a smaller heat affected zone.
The effects of the steel’s surface quality on the properties of anti-corrosion coatings
Authors: Herbath B. , Kovacs K. 
Published: August 2020

Abstract
The requirements of painted vehicle construction in terms of corrosion resistance apply not only to cars but also to heavy duty lorries, trucks and agricultural machinery. Phosphating is the most commonly used method for the pre-treatment before painting of ferrous metals in the vehicle manufacturing industry. The task of the phosphate layer between the metal surface and the paint is to protect the metal from corrosion under the paint film and promotes the adhesion of the paint film to the metal substrates. In this study the zinc phosphate conversion layer was deposited onto the steel surfaces from a bi-cationic (nickel-free) phosphating bath by dipping using identical technological parameters. The developed crystal structure and morphology was examined in terms of surface roughness and blasting quality of the metal. The surface quality of the metal was tested by digital light microscopy (LM), and the structure of phosphate coating was investigated by scanning electron microscopy (SEM).
Microstructure examination of additive manufactured 316L steel
Authors: Dávid Miklós KEMÉNY , Dávid PAMMER , Dorina KOVÁCS 
Published: August 2020

Abstract
The additive manufacturing (AM) is a new field in research. In our research, the samples were made by direct metal laser sintering (DMLS). During the production of 316L material, the piece was formed layer by layer, so the existing layer was re-heat treated when the new layer was formed. Due to the multiple heat treatment, the post-heat treatment of the product is necessary. Microstructure changes were investigated after two different heat treatments. The first was at 450 °C for 4.5 hours, and the second was at 1100 °C for one hour, followed by annealing in each case. The heat-treated sample at 450 °C showed no significant difference. In contrast, the sample heat-treated at 1100 °C the particles were better separated, and segregation in grain boundary was observed, which showed high phosphorus concentration.
Magneto-acoustic investigation on steel samples
Authors: Szabados O. , Baki R. , Zs  , Csincsi  , Molnar J. , Pámer Á. , Szabó P. , Por G. 
Published: August 2020

Abstract
Experiments have been carried out using yoke for energizing alternating magnetic field in the steel samples. We used acoustic emission sensors and ultrasound microphone for recording acoustic signal born in the steel material. Results of experiments clearly show the presence of Acoustic Barkhausen noise. We are introducing graphs presenting dependence of acoustic time response signal on magnetic signal (inductance) in form of Lissajous curve. It is claimed that this new method gives more in-sigh in the material than the widely used simple RMS measurement of acoustic response.
Deformation-softening in ultrafine-grained materials
Authors: Gubicza Jenö , Quang Chinh Nguyen 
Published: August 2020

Abstract
Plastic deformation is conventionally considered as a route for strengthening of metallic materials. During plastic straining, different crystal defects, such as dislocations, stacking faults and grain boundaries form, hardening the material. On the other hand, plastic deformation may also cause unexpected softening in ultrafine-grained and nanocrystalline materials. This paper summarizes the existing knowledge on this deformation-softening effect.
Root cause analysis of metallurgical defects in continuous cast steel slabs at ISD DUNAFERR Zrt.
Authors: Wizner K , Kővári A 
Published: August 2020

Abstract
As market demands tighten, ISD Dunaferr Zrt. is placing increasing emphasis on improving the quality of its products. Line Scanner equipment used in rolling mills can identify most surface defects, but the majority of metallurgical faults are located beneath the surface (e.g. inclusions, cavity, gas bubbles, etc.). There is no standardized device for detecting them, only ultrasonic and microscopic testing is possible. In addition, it should be noted that some of the defects detected on the surface (e.g. surface cracks) can only be determined by microscopic testing, whether they are metallurgical or due to the parameters of the rolling process. Several pilot programs have been implemented to explore the causes. In this theme, the most significant pilot programs, as well as the evaluation of their results will be presented.
Joining aluminium and poly(lactic acid) specimens by laser beam – a feasibility study
Authors: Temesi T , Czigany T 
Published: August 2020

AbstractIn this article, our main aim is to demonstrate and prove that it is feasible to join aluminium and poly(lactic acid) (PLA) specimens by laser beam. We investigated the effects of structuring the surface of the aluminium specimens with corundum blasting and joining speed and used three types of PLA (with the same D-lactide content but different average molecular weights) to investigate the effect of the viscosity of the polymer melt on the load-bearing capacity of the joints. Joined aluminium-PLA specimens were successfully manufactured and examined with standard lap-shear tests. We found that both surface structuring, joining speed and the type of PLA material influenced the load-bearing capacity of the aluminium-PLA joint.
Manufacturing and investigation of aluminium matrix bimodal metal foams
Authors: Leveles B , Kemény A , Orbulov I N 
Published: August 2020

Abstract
Metal matrix foams (MMFs) are mostly used in the automotive industry due to their high specific energy absorbing capacity and relatively low weight. During this research, bimodal metal matrix foams were produced, where the filler was ceramic hollow spheres (CHSs) made of high-purity alumina with the nominal diameters of Ød1 = 7 mm and Ød2 = 2.4 mm. The hollow spheres of different sizes were used in 1:1, 2:1 and 4:1 volume ratio, which after mixing can be considered as uniformly distributed. Al99.5 was infiltrated between the CHSs with low pressure to create a cellular material. The manufacturing parameters have a significant influence on the properties of the finished metal matrix foam. Different preheating temperatures, melt temperatures, infiltrating pressures and time was applied to achieve proper wetting and filling. Samples were evaluated based on macro images and microscopic photographs.
Numerical modelling of the thinning behaviour of sheet metal parts
Authors: Gál V , Lukács Zs 
Published: August 2020

Abstract
In the automotive industry there are several software for numerical simulations to predict the behaviour of the material, which can reduce the expensive try-out experiments and dies cost. These software uses different mesh types. The goal of this work is to compare the different mesh element types in sheet metal forming simulations from the viewpoint of excess thinning. The benchmark of the 2018 NUMISHEET conference was the base of this comparison. This benchmark investigates the formability of a 2.8 mm thick, hot rolled sheet with 440 MPa tensile strength. The FE modelling of the process was made with thin shell-, thick shell-, and brick element types, thereafter; it was validated by the minimum thickness of the part based on physical data measurement. To better identify the differences due to the mesh elements, the thickness distribution of the part was investigated, too.
A comparative analysis of characteristics of cutting forces at micro-milling of hardened steels
Authors: Balázs B Z , Takács M 
Published: August 2020

Abstract
Abstract Micro-milling is one of the most important technologies to produce miniature components. Mainly due to the size reduction, the process has many special characteristics, such as the relatively large tool run-out, the relatively large deformation and the cutting edge radius of the micro-milling tool. The cutting force is often correlated to the phenomena mentioned above, its analysis is therefore often required. The main objective of the present paper is to analyse and compare the characteristics of cutting forces in micro-milling of different hardened steels. A systematic series of experiments were conducted on a hardened AISI H13 hot-work tool steel and a Böhler M303 martensitic corrosion resistance steel. The hardness of both materials is 50 HRC. A 500 µm diameter two fluted carbide micro end mill and a five-axis micromachining centre were applied. The effects of the cutting parameters are analysed by the analysis of variance (ANOVA). Experimental results show that the workpiece material has a significant influence on the cutting forces.
Investigation of the energy absorption properties of cross-linked polyethylene foams
Authors: Tomin M , Kmetty Á 
Published: August 2020

Abstract
We performed the dynamic mechanical investigation of cross-linked polyethylene (XL-PE) foams, which are the most commonly used polymer foams for damping purposes. Our experiments were primarily focused on analyzing the energy-absorbing capability of foams with different densities and studying the relationship between cell structure and shock absorption. The cell structure and energy absorption properties of the foams were determined by mechanical tests and microscopic examination. The samples were subjected to falling dart and falling weight impact tests using different weight geometries and impact energy. Our experiments showed that the impact damping properties of foams are significantly influenced by the deformation mechanisms in the cellular structure during dynamic loading since excessive deformation of the cell walls leads to the compaction of the foam, and therefore a significant reduction in impact damping capability.
On the relationship between parameters of melt spreading over the surface of substrates of variable composition and state diagrams
Authors: Bagov A M , Khasanov A I , Zubhadzhiev M-A V , Umarova L Kh 
Published: August 2020

Abstract
On of metered-dose drops of various concentrations on a substrate of variable composition. The basis for the substrates and droplets is the contact melting (CM) method related to state diagrams which are used to study the concentration dependence of surface characteristics (spot shape and size, wetting and spreading, surface tension, etc.) under the same conditions which improves accuracy of the characteristics. It was found that the microstructure of the transition zone of the substrate-drop depends on the location of the drop on the substrate, i.e. on the concentration of the substrate.
The study of application of Maslyanites in pumps designed for pumping aggressive media
Authors: Bataev D K-S , Goitemirov R U , Dzhamaldinova M A 
Published: August 2020

Abstract
For experimental studies, chemically active aggressive media pumped by single-screw metering pumps (SSMP) were used. The effect of these media on the destructive compressive stress, tensile strength, elongation, hardness, degree of swelling, antifriction properties and wear resistance of the polymer composite material Maslyanite D (S-1) was studied. It was established that hardness and antifriction properties of Maslyanite D (S-1) are better than those of SKN-26-based rubber 8470.
The use of carbon nanotubes in the fire extinguishing of oil and oil products
Authors: Dali F A , Shidlovsky G L , Khasikhanov M S , Zalaev R U , Tagirova P R , Saidulaev S S , Masaeva L M , Erzhapova R S 
Published: August 2020

Abstract
The process of quenching a flame of liquid hydrocarbons by suspensions of water with carbon nanostructures is studied. It is shown that the dispersion of carbon nanostructures in water intensifies heat transfer in liquids, which leads to their more rapid heating to boiling temperature under conditions of thermal exposure to a flame. During the experiment, it was found that the quenching time of liquid hydrocarbons by nanosuspensions is on average 3.5–5.0 times less than the time of quenching of a liquid with finely divided water.