bluuebunny/crossref_metadata_2025_split huggingface dataset:
Impact characteristics of gustiness debris flow on check dam
Authors: Jiang X G , Liu F W , Hu K H , Liu T , Wang H J , Li L , Zheng S Y , Chen Y , Song S J , Wang Y D 
Published: October 2019

Abstract
The gustiness is a common motion form of debris flow, especially viscous debris flow. However, few researches have considered the gustiness into the impact characteristics of debris flow, which needs further research. In this study, the check dam was used as the load receptor to study the impact characteristics of gustiness debris flow. The results show that, under the same general flow depth, the dam stress considering the impact of gustiness debris flow is far less than that of disposable continuous debris flow. The impact force increases with the increase of the times of gustiness debris flow, and the impact torque increases linearly. Under the impact of gustiness debris flow, the displacement and stress of the dam vary in the same rule. The safety factors of anti-sliding and anti-overturning of the dam under the effect of gustiness debris flow are larger than those of disposable continuous debris flow, and the decrease rate of the safety factors increases with the increase of the times of gustiness debris flow. And under the condition of the same total flow depth, the increase of the debris flow depth can significantly decrease the stability of dam. The conclusions can provide reference for the design of blocking structures of gustiness and frequent debris flow.
Numerical investigation of plane wave propagation in three soil models and a simple viscoelastic treatment of the boundary considering gravity using MPM
Authors: Zhang R Y , Haider A 
Published: October 2019

Abstract
The importance of plane wave propagation in geotechnical engineering problems considering both small and large deformation is well understood but the theory of wave propagation in the latter is maybe not mature. In this paper, the mechanism of plane wave propagation in constitutive models such as linear elastic model, Mohr Coulomb model (MC) and elastoplastic density-dependent model (DDSM) considering finite deformations is extensively studied using the material point method. The classical laws of wave propagation and reflection in a continuum are found to provide reasonable explanations to the considered problems. The stress propagation mechanism in the three models considered is mainly related to the variation of the material wave impedance. An accurate silent boundary condition is found difficult even impossible to be determined for complicated models, which is verified by a simple deduction. Moreover, a simple viscoelastic silent boundary is proposed to consider the realistic effects of gravity in geotechnical engineering problems and its performance is compared with that of the classical viscous boundary for truncating a 1D linear elastic half-space.
Simulation analysis of liquid sloshing under different working conditions of hazardous materials rescue truck
Authors: Zhou S W , Liu Z H 
Published: October 2019

Abstract
The geometric model is built with SOLIDWORKS, and the VOF(Volume Of Fluid) method in the CFD(Computational Fluid Dynamics) software fluent is used to simulate the sloshing characteristics during the brake and steering of the Hazardous Materials Rescue Truck. The braking acceleration, the liquid filling ratio of the vehicle, lateral acceleration, the effect of the baffle during braking and steering are respectively studied. The results show that the steering and braking of Hazardous Materials Rescue Trucks will cause the liquid in the tank to slosh, and the liquid sloshing will cause the wall slosh force of the tank to change. The driving stability of Hazardous Materials Rescue Trucks can be effectively improved by the reduction of braking force, proper liquid-filling ratio, reduction of lateral acceleration, and increase of baffles.
Composite scattering from complex conductor-medium assembly object above a rough surface
Authors: Li N , Xie S J , Tian G L , Wei S J 
Published: October 2019

Abstract
To solve the scattering from complex object combining conductor and medium, this paper proposes a hybrid iterated method combining single integral equation (SIE) and Kirchhoff approximation (KA). Firstly, SIE is used to calculate the electromagnetic current in the facet of the conductor-medium assembly object. Then, the electric and magnetic currents on the facet of a rough surface are calculated by KA. The electromagnetic current on the facet of object and a rough surface are updated by mutual iteration. Finally, some examples for composite scattering from object above a rough surface are analysed and discussed in detained.
Lattice Boltzmann simulation of the methane backward flow in coal mine tunnels after methane outburst
Authors: Wang Q J , Zhao Y C , Nie Y 
Published: October 2019

Abstract
Numerical study of the methane backward flow in coal mine tunnels after a methane outburst is necessary to the engineering design and emergency rescue. In this paper, we introduce Lattice Boltzmann Method (LBM) coupled with the Large Eddy Simulation (LES) model to simulate the methane backward flow in the air-intake tunnel of twin-tunnel construction in the coal mine after the methane outburst and analyze the effects of the inlet air velocity, the intensity of the methane outburst and the width of the tunnel to the distance that the methane can flow backward. It demonstrates that with the increase of the inlet air velocity, the distance that the methane can flow backward decreases. With the increase of the intensity of the methane outburst, the distance that the methane can flow backward increases. There exist linear relationships between the inlet air velocity, the intensity of the methane outburst and the distance that the methane can flow backward. The change of the tunnel width has almost no influence on the distance that the methane can flow backward.
Study on wind-induced response of a simplified model of transmission tower based on finite particle method
Authors: Huang Z , Liu S , Nie M , Yang Y , Gao Q S , Zhang C 
Published: October 2019

Abstract
A reduced model of a transmission tower was established based on the principle of equivalent stiffness. The finite particle method was used to analyse the wind-induced response of the reduced model. The analysis of the dynamic characteristics of the reduced model shows that the accuracy of the equivalent formula proposed in this paper was very high. Compared with the first five order natural frequencies of the complete model, the maximum calculation error of the reduced model was only 0.87%. Since the first order shear deformation beam theory was used in the reduced model, the interpolation-independent element shape functions were developed to avoid the shear locking phenomenon. Moreover, the formula for calculating the internal force of Timoshenko beam for finite particle method was derived. By using two successive Euler angles, a new method for separating the rigid motion and pure deformation of the element was proposed. The computational efficiency of this method is significantly improved, and the computational time is less than half of that of the traditional finite particle method. The results of wind-induced response analysis of the transmission tower show that the simplified model proposed in this paper can obtain highly accurate displacement response of the structure, and the maximum error of the RMS of the displacements at the top of the tower is less than 3.2%. This model is suitable for studying the dynamic response of transmission tower line system and evaluating the effect of the wind-induced vibration control of damping device.
A damage constitutive model and its characterization parameters identification for elastic-plastic materials
Authors: Wang C H , Jiang W X , Xin K H , Wang J , Ji H J 
Published: October 2019

Abstract
This paper proposes a simple damage constitutive model for elastic-plastic materials on the basis of the classical elastic-plastic constitutive model and damage mechanics theory. Based on the simple damage constitutive model, ABAQUS built-in Python software was used to develop the virtual experimental platform, and the whole process simulation of the specimens stretching until the fracture was carried out. The correspondence between the damage characterization parameters and the performance indexes such as the fracture strain and the percentage reduction of area was studied. According to the comparison of the virtual/real test results of ZL114A, the situation shows that the simple damage constitutive model can realize the high fidelity simulation of the damage behavior of elastic-plastic materials. The relative accuracy of the important material property parameters such as the ultimate strength, the percentage total elongation at fracture and the percentage reduction of area reaches 5%.
Investigation of gas-dynamic processes in a boundary layer on a basis of molecular dynamics simulation
Authors: Kuryashova T A , Podryga V O , Polyakov S V 
Published: October 2019

Abstract
The work is devoted to numerical simulation of the nonlinear gas dynamic processes in technical systems of micron sizes. This problem is relevant for many applications related to the implementation and the use of nanotechnology in various industries. As an example, a gas flow in micro channel with metal walls is considered. Within this problem, we are interested in a calculation of the boundary layer parameters from first principles. The numerical analyses are carried out according to the Newton's equations of classical dynamics. The model under consideration takes into account the molecular composition of the gas, the atomic structure of the metal surfaces, and heat exchange of the gas with the metal. Computer implementation is focused on using high-performance systems with hybrid architecture. The calculations are performed on the example of a nitrogen flow into a nickel micro channel for several micro channel lengths. The flow velocity varied over a wide range. It is considered in the subsonic, transonic, and supersonic ranges. In numerical experiments, macro parameters of gas flow in the boundary layer are obtained and the corresponding near-wall model is formed. It can be used for the calculation of flows in micro channels using continuum mechanics methods.
Forecasting methods in engineering
Authors: Tratar L F , Strmčnik E 
Published: October 2019

Abstract
Forecasting in engineering is one of the most important topics when it comes to optimisation, which is related to energy savings, material savings, increasing efficiency, and appropriate and correct decisions at the level of a company, institution, city, or region. Moreover, forecasting is indirectly related to cost savings and the sustainable development of society and environment. In the energy industry (electricity, natural gas, heat load), there are requirements to balance the supply and demand. Markets are very dynamic, and for this reason forecasting is more challenging. Forecasting errors are usually penalized drastically. However, a well-developed forecasting approach represents a competitive advantage, and so a company may significantly reduce expenditure and increase profits. Many publications on forecasting have been published during recent years. Long-term forecasting methods offer many opportunities for strategic planning and optimal scheduling, whereas a short-term forecasting approach would help attain optimal daily operations and the maximum utilisation of the company’s resources. Although different forecasting techniques can be used, the major conclusions are that exponential smoothing methods are the simplest and the least expensive. Distinguished by their simplicity, their forecasts are comparable to forecasts of more complex statistical time series models. In this paper, the forecasting performance of Additive, Multiplicative, and Extended Holt-Winters methods were analysed. We also analyse whether the data format influences the choice of the forecasting method: is the most accurate method for monthly data also the best method for quarterly data?
Numerical study on flow around vane in a channel using immersed boundary method
Authors: Huang J F , Yang S , Yao J , Zhang L X 
Published: October 2019

Abstract
The immersed boundary method is applied to simulate the flow around a guide vane of hydro-turbine. The complex dynamic boundary effect caused by the moving guide vanes is modelled as the forcing term in the Navier-Stokes equation. Numerical simulation of threedimensional transient turbulence is conducted to flow around one moving guide vane of a benchmark hydro-turbine unit in a channel. The dynamical Smagorinsky-Lilly model of large eddy simulation is also used. The evolution process of the dynamic vortex structure is obtained by the interaction between the guide vane and the flow around vane to reveal the physical mechanism of wake oscillation flow around vane. This method serves as a reference for the fine simulation and study of the flow around the multi-stage cascade flow in hydro-turbine. The research on the transient effects of the coupling upstream pipeline system and hydroturbine has theoretical guiding significance.
Influence of different oil-paper configurations on the electric field distribution simulation of the internal insulation of converter transformer
Authors: Cheng Z D , Cheng L , Wang J H , Wang L 
Published: October 2019

Abstract
Converter transformer is an important equipment in HVDC system and it is the key to the stable operation of the whole power transmission and distribution system. Unlike the traditional AC transformer, the oil-paper insulation of converter transformer will receive both AC and DC voltage. So the requirement for the structure design of oil-paper insulation system will be more stringent. It is of great engineering significance to study the electric field distribution of converter transformer and to study the influence of different oil-paper insulation configuration on the electric field distribution in the internal insulation of converter transformer. In this paper, first, an oil-paper insulation structure of converter transformer is established and electric field distribution under AC/DC composite voltage is studied. Then change the thickness and layers of pressboard, the distance of oil channel and the oil-paper ratio to get different oil-paper configurations. Use the simulation software to calculate the electric field distribution under the different oil-paper configurations. Finally, the influence of different oil-paper configuration on the electric field distribution of internal insulation structure of converter transformer is analysed which will provides significant reference for the internal insulation design of converter transformer.
Numerical modelling and vibration analysis of human middle ear for application in sound conduction reconstruction
Authors: Liu Y , Higashimachi T , Toriya R 
Published: October 2019

Abstract
In this paper, we introduce a new numerical approach for estimating the hearing restoration eect prior to the tympanoplasty operation using the nite element harmonic vibration analysis. This kind of approach makes it possible to propose a new medical treatment for the recovery of conductive or cochlear hearing loss. First of all, precise geometric models of the middle ear, including healthy type model and tympanoplasty type models, are constructed on the basis of the computerized tomography (CT) scanning data. Then, frequency response characteristics of the stapes displacement in sound conduction are claried using the three-dimensional nite element harmonic vibration analysis. Based on the investigation results, we propose that the hearing restoration eect can be estimated by a comparison of the dierences in the stapes displacement between the reconstruction model and the healthy subject.
Weak-form differential quadrature element method for dynamic analysis of fluid-saturated soil
Authors: He G H , Kuang Z H , Li X K 
Published: October 2019

Abstract
It is formulated the weak-form of differential equations that govern the two-dimensional dynamical behavior of fluid-saturated soil, then the weak-form equations are discretized by the differential quadrature technique, and finally solved by the implicit Euler method. The proposed weak-form equations and numerical programs developed are verified through comparisons with benchmark solutions, and the convergence performance of the presented method is investigated. Numerical results show that the proposed weak-form quadrature element method not only possesses significantly higher computational efficiency, for the dynamic analysis of saturated soil, than the conventional finite element method, but it is also significantly alleviated the problem of numerical smoothness in the stress analysis.
Influences of various orifice layouts on the properties of aerostatic journal bearings based on finite element method
Authors: Gao S Y , Shi Y G , Yang S , Sun P , Li T J 
Published: October 2019

Abstract
It is essential to thoroughly investigate influences of orifice layouts on properties of aerostatic journal bearings employed in ultra-high speed spindles. In this paper, four orifice layouts of aerostatic journal bearings which have a large length-diameter ratio are designed and investigated, particularly in light of the nonlinear compressible Reynolds equation and the associated computational analysis and algorithms using the FEM-based Galerkin weighted residual method. A series of pressure distributions as well as the load capacity, attitude angle, volume flow rate and air film stiffness of the aerostatic journal bearings for the cases of four orifice layouts are analysed with respect to different rotational speeds and eccentricity ratios. It can be concluded that increasing orifice sets is not beneficial to enhance the performance of the aerostatic journal bearing. The aerostatic journal bearing divided into two identical independent aerostatic journal bearings has relative optimal performance at rotational speeds from 0 r/min to 160,000 r/min, such as the highest load capacity, the lowest attitude angle and modest air film stiffness, however, with consumption of the largest quantities of pressurized gas. The designers can use the analysis results to optimize the orifice layout for improving the performance of the aerostatic journal bearing.
Optimizing basket transplanting parameters using the mechanical properties of tomato plug seedlings
Authors: Liu Y , He Y C , Li Y X , Mao H P , Li B , Wang T , Wang S G , Li H 
Published: October 2019

Abstract
The collision between tomato plug seedlings and the planting device during basket transplanter function causes the seedlings’ root lump to lose some mass. To resolve this problem, we establish a contact mechanics model using Hertzian contact theoretical and Newtonian methods, enabling us to formally derive the maximum deformation of the root lump. The equation of motion describing the collision between the tomato plug seedling and planting device is constructed using the principles of impulse and momentum. Then, we identify the optimization function of contact angle θ—which consists of the maximum deformation of the root lump, the angular velocity of the tomato plug seedling, and the absolute velocity of the root lump—via multi-objective methods. When the angular velocity of the planting device is 1.05 rad/s or 1.15 rad/s, the optimal contact angle is 67°. Further, we examine the velocity of the tomato plug seedling after collision. A small plant height reduces the root lump’s mass loss; we found that 12-cm-tall tomato plug seedlings lose less root lump mass than taller seedlings. Finally, for angular velocities of 1.05 rad/s and 1.15 rad/s, we carry out of tomato plug seedling crush tests with the optimized parameters, achieving minimum root lump mass losses of 8.76% and 7.43%, respectively.
Experimental investigation on micro-drilling properties of Mg-based MMCs reinforced with HAP nanoparticles
Authors: Sun F Z , Fu G Y , Shen J R 
Published: October 2019

Abstract
Mg-based metal matrix composites (MMCs) reinforced with Hydroxyapatite (Ca10(PO4)6(OH)2, HAP) nanoparticles have been studied as bone substitute materials because of their excellent biocompatibility and biological activity. In this paper, Mg/HAP MMCs with different HAP contents (0.5, 1.0 wt%) were selected and the micro-drilling properties were revealed. Firstly, the chip of MMCs was analyzed. Secondly, the surface roughness of Mg/HAP MMCs under different cutting parameters was studied. The results showed that the surface roughness decreases with the increasing of feedrate and decreases with the increasing of spindle speed, which are contrary to pure Mg. Furthermore, the shapes of burr are all classified as uniform burr, and the burr height increased with the increase of spindle speed and feed. Finally, the size effect of micro-drilling was studied. The minimum cutting thickness per tooth of Mg/HAP MMCs was determined to be 1.0 μm.
Application of resonance demodulation method based on local characteristic-scale decomposition and spectral kurtosis in gearbox fault
Authors: Cong R , Li C H , Wu J Q 
Published: October 2019

Abstract
Resonance demodulation technology has been widely used for its advantages on magnification and selection of fault information. However, the selection of filter parameters is affected by the subjectivity, and the analysis results are easily affected by the noisy signals under actual working conditions. To solve this problem, a method combining relative entropy and correlation coefficient is proposed to analyze and select Intrinsic Scale Components obtained by Local Characteristic-scale Decomposition, remove false components, and to some extent, denoise. Then, after reconstructing the remaining components, we use spectral kurtosis analysis to find out the most easily detected frequency bands of fault features and analyze them by resonance demodulation, aiming to diagnose gearbox failures. Finally, we compare this method with that based on the empirical mode decomposition. The research shows that the method proposed in this paper can effectively diagnose the gearbox fault and is better than the empirical mode decomposition.
Numerical analysis of mini-channel cooling applied in power battery
Authors: Huang F X , Zhao J , Wang C , Zhang H 
Published: October 2019

Abstract
Working in the extreme condition such as high temperature and discharge rate, causes the generated heat shapely increasing and rising of temperature of power battery. Further influence the cell performance. It is important to efficiently dissipate heat. In this paper, a minichannel cooling system can be designed to cope with the problem. Moreover, creating numerical model to study different placement, ambient temperature and coolant inlet properties how to function on the system. The results express the system be placed at vertical direction can obtained a good temperature effect, only sacrificing few of pump energy than placed at horizontal. The results show the variation of ambient temperature has little effect on the temperature contribution of battery module, and the temperature of the battery pack is presented linear with the coolant inlet temperature. The temperature of battery pack is decrease and the uniformity is improved by increasing the inlet velocity of the coolant. In the end, increasing the height of the channel are a better scheme through the process of structure optimization.