bluuebunny/crossref_metadata_2025_split huggingface dataset:
Various Flow-Field Designs for Enhancing Fuel the Cell Performance of Proton Exchange Membrane Fuel Cells
Authors: Diep Tran Thi , Ha Vu Duc , Huang Shoudao , Vinh Nguyen Duy 
Published: February 2020

AbstractThe flow-field design is an essential key in the operation of fuel cells, it conducts main functions such as contributing reactants to the membrane electrolyte assembly (MEA) over gas diffusion layers, conductive part, clamping MEA as well as water management & thermal management and so on. As a result, it is necessary to optimize the flow-field design of fuel cells in order to enhance fuel cell operation characteristics. This paper shows numerical analyses of fuel cell characteristics based on 4 configurations of flow-field in order to find out the best design for enhancing fuel cell performance. The results showed that the different design of flow-field for the anode side and the cathode side can contribute to enhancing fuel cell operation characteristics due to their difference in water formation and discharge. Indeed, the fuel cell configuration with the serpentine flow field in anode side and the pin flow field in the cathode side is the best design because it leads to reducing the water flooding in the cathode side and drying in the anode side. The maximum power density of configuration 1-4 is 0.515, 0.528, 0.585, respectively. It means an improvement of 13.6% percentage can be observed. The research results of this research are the foundation of optimizing the design of the flow-field design.
Effect of Road Surface Contour to the Fatigue Life of a Coil Spring Based on Strain-Life Approach
Authors: Putra T E , Husaini  , Ikbal M 
Published: February 2020

Abstract
This study aims to determine the effect of road surface contours to the fatigue life of an automotive coil spring. A strain gauge was affixed at the critical point based on the stress distributions. The vehicle passed smooth and rough roads with the speeds above 30 km/h and less than 20 km/h, respectively. The strain signals obtained were analyzed using the Coffin-Manson, Morrow, and Smith-Watson-Topper models. According to the analysis, when the vehicle passed the rough road, the coil spring received a higher stress leading to a shorter fatigue life, of 1,284 cycles to failure. This value was 526 % lower compared to the smooth road because it consisted of bumps and holes.
Effect of Concrete Surface Crack Filling Conditions on Dominant Frequency of Surface Rayleigh Wave
Authors: Hoe Liew Chi , Wei Lee Foo , Ghuan Tan Chee , Zee Kwong Kok , Lim Kok-Sing 
Published: February 2020

Abstract
Elastic Surface Rayleigh Wave (R-wave) based non-destructive test (NDT) techniques have been studied broadly for concrete surface crack assessment in the past few decades. However, the effect of environment factors on the accuracy of R-wave NDT results are often being neglected. Sand and dust are ones of them that easily accumulate within the surface cracks of concrete structures, which potentially affect the characteristics of R-waves propagation when it travels through the concrete medium that containing cracks. This study is aimed to investigate the effect of concrete surface crack filling conditions to the dominant frequency of R-wave. Numerical simulations were conducted to study the changes of R-wave waveform when it propagated through a cracked concrete model with two various filling conditions, namely fine sand and charcoal powder. Fast Fourier Transform (FFT) for post-signal-processing (PSP) of raw R-wave signals to determine its dominant frequency. The results of numerical simulations were then justified by experimental measurements. It was found that the dominant frequency of R-wave is independent to the volume and the type of filling materials, but sensitive to the surface discontinuity of the concrete.
The Effect of Nano Ceramic Powders On Mechanical and Physical Properties of Normal Concrete
Authors: Jawad Kadhim Zainab , Raad Al-Adhadh Ahmed , Ali sabur Dhay 
Published: February 2020

Abstract
Concrete is one of the most important materials used in construction. Properties of concrete can be improved using additives like nano-ceramics which acts as reinforced phase to raise the mechanical properties of concrete. Effect of nano-powder on some properties of concrete has been determined. In this study, two concrete mixes have been prepared, first one, by adding different contents of nano–ZrO2, second using nano – Al2O3 powder. Properties of concrete have been studied through the compressive strength, Splitting tensile strength, workability and water absorption. Results showed that the slump reduced from 103 mm to 62 mm when 1.1% nano-zirconia added, the same behavior observed in mix that contain nano alumina powder. The compressive strength increases when nano-zironia added, the maximum value of compressive strength obtained when 0.7% nano-zirconia added (45.3 MPa at 28 days, 48.3 MPa at 60 days and 52.3 MPa at 90 days). Moreover, splitting tensile strength was improved with increasing nano-zirconia content and the maximum values were at 0.7% of nano-zirconia, (5.2 MPa at 28 days, 6.6 MPa at 60 days and 8.2 MPa at 90 days), water absorption decreased when nano-zirconia percentage increased (0.12 % at 28 days and 0.1 % at 60 and 90 days). In this research, it is also observable that nano alumina powder has more influence for enhancing concrete properties than zirconia powder. Compressive strength and splitting tensile strength of concrete mix with nano alumina increased highly with increasing content of Al2O3 and reach its optimum value at 1.1 % of Al2O3 in NA6. Alumina powder has a high ability to diminish pores size and to increase density of concrete mixture; so, low permeability, low water absorption concrete produced.
Photobioreactor Simulation for Microalgae Chlorella Cultivation in Process
Authors: Trofimchuk Oksana A , Romanenko Sofia A , Turanov Sergey B. , Yakovlev Alexey N. 
Published: February 2020

Abstract
Three-dimensional simulation of light fields in the photobioreactor for Chlorella cultivation was performed. It was shown, that light flux reduced due to the increase of optical density and growth of microalgae cells concentration. According to the fact that light intensity is an important factor, affecting growth rate and development of microalgae cells, process automation and light flux increase in dependence to Chlorella cells gain are needed to be introduced [1-3].
Nonlinear elastic analysis of concrete beams based on the Smeared Crack Approach
Authors: Betancourt N , Arias C , Durán F , Arana V 
Published: February 2020

Abstract
In the present study, an analysis of plain and reinforced concrete beams under monotonic loading was made based on the Fixed Smeared Crack approach. The objectives of this research were to analyze the nonlinear behavior of the selected cases of analysis and to propose an alternative and simple model for the analysis of beams under service loadings, by means of Committee 435 of the American Concrete Institute. A brittle model for concrete and a linear-elastic behavior for steel reinforcement bars were considered. Results are presented through force-displacement curves and the sequence of cracking propagation. Also, a comparison of calculated instantaneous deflections of simply supported beams was made between the proposed model and other researches. It was verified that the proposed algorithm can predict adequately the cracking process and the deflections of beams subjected to service loadings, taking into account experimental results from other authors.
Optical Properties of Cd-Free Quantum Dots-Based Fluorescent Film
Authors: Lin M Y , Lin W X , Chung S R 
Published: February 2020

Abstract
CuInS2/ZnS Cd-free quantum dots (QDs) have many characteristics, such as high quantum yield (QY), wide emission peak and adjustable light color. They are suitable for optical conversion materials and applies in solid-state lighting (SSL). However, they are not easily dispersed during encapsulation, resulting in the deviation of light color out of the white light area after encapsulation. In this study, we use thermal injection synthesis method to prepare CuInS2/ZnS and CuInS2/ZnS:Al QDs. In order to improve the dispersion of QDs, solution type of QD/PS-PE-BR-PS copolymer (SEBS) mixture was prepared by mixing QD and SEBS with different ratios (10, 20, and 30 wt%) to form a fluorescent film. The experimental results show that the emission wavelengths and QY of CuInS2/ZnS and CuInS2/ZnS:Al QDs are 533 nm, 84 % and 536 nm, 97 %, respectively. The emission wavelength of CuInS2/ZnS-based fluorescent film is 574 nm, while CuInS2/ZnS:Al-based fluorescent film is 582 nm. The CRI, luminous efficacy, chromaticity coordinates and correlated color temperature of 20 wt% CuInS2/ZnS-based fluorescent film excited by blue chip is 64, 42 lm/W, (0.33, 0.32), and 5443 K, respectively. On the other hand, we find that the CRI of CuInS2/ZnS:Al-based fluorescent film can be improved from 64 to 73, and the luminous efficacy is 51 lm/W.
Gravel Sampling for Testing
Authors: Al-Rumaithi Ayad , Al-Sherrawi Mohannad 
Published: February 2020

Abstract
Sampling is the selection of a representative portion of a material, and it’s as important as testing. The minimum weight of gravel field or lab sample depends on the nominal maximum particle size. The weight of the sample will always be greater than that portion required for testing. The approximate precision desired for the testing will control the weight of the gravel sample. In this study, gravel sample has been simulated by using multilinear approximated function for Fuller’s curve on the logarithmic scale. Gravel particles are divided into classes according to their medium diameter and each class was simulated separately. A stochastic analysis, by using 100 realizations in sampling, has been done and the root mean square error for the errors between sampled and target curve has been discussed for two selected samples of coarse aggregate.
Numerical Analysis on Seismic Performance of a New Type of Fully Assembled Beam-Column Joints
Authors: Zhai W , Jiang W , Yang J H , Yang J F , Qu K , Chen L 
Published: February 2020

Abstract
To investigate the seismic performance of a new type of fully assembled beam-column joints, finite element models are established by ABAQUS with the nonlinear and geometric nonlinear effects considered to simulate 5 joints based on the quasi-static test. Through the comparison between finite element analysis and experimental results, the validity of finite element models is verified. Then the correlation parameters and their effects on the seismic performance of joints are analysed.
Stable Colloidal Silica Particles Doped with a Fluorescent Dye
Authors: Mulikova Tomiris , Khamkhash Laura , Dukenbayev Kanat , Molkenova Anara , Sh. Atabaev Timur 
Published: February 2020

Abstract
In this study, we described the quick synthesis strategy of stable colloidal silica particles encapsulated with a fluorescent dye. Atomic Force Microscopy AFM, Fourier-Transform Infrared Spectroscopy FTIR, and Fluorescence Spectroscopy FS were utilized to characterize the obtained silica particles. AFM analysis revealed that obtained silica particles have a spherical shape with a mean size of 210 ± 13 nm. FS analysis showed that fluorescent dye was successfully incorporated into a silica matrix. In particular, eye-visible green fluorescence emission with a peak maximum at 526 nm was detected. The emission stability of prepared particles was tested in a biologically-relevant pH range, under constant UV irradiation and at different storage time intervals.
A Comparative Study of Hyperelastic Constitutive Models to Characterize the Behaviour of a Biopolymer Material for Diaphragm of Blood Pump Manufacturing
Authors: Belyaev L. V. , Zhdanov A. V. , Ivanchenko A. B. , Stepenkin A. V. , Kochetov D. O. 
Published: February 2020

Abstract
This article presents the results of the stress-strain state modelling of a blood pump diaphragm manufacturing from polyurethane ‘Vitur’ T-1413-85 for pulsatile type Ventricle Assist Device systems. Based on the analysis of the most distributed models of hyperelasticity, a model which most accurately describes the behaviour of the specified material has been determined (R2 = 0.9999 between numerical simulation and experimental uniaxial tensile tests data). Experimental studies have been carried out to determine the displacement of the diaphragm with a thickness of 0.3 mm and 0.5mm under the influence of control pressure. A comparison of the modelling results of the blood pump diaphragm stress-strain state and the conducted experimental studies on the determination of displacements confirmed the adequacy of the chosen model (R2 = 0.96 between numerical simulation and experiment) for both of the studied diaphragm thickness.
Forecasting Change of the Roller Screw Mechanism Efficiency on the Basis of a Comparative Analysis of Coated Surfaces
Authors: Belyaev L.V. , Zhdanov A. V. , Dovbysh N. S. , Morozov V.V. 
Published: February 2020

Abstract
The paper presents the results of the influence of materials, lubricants and the type of coatings in friction roller screw mechanism on the values of the coefficient of friction and the coefficient of efficiency required to predict the efficiency of the drives. Theoretical studies were carried out for different types of roller screw mechanism coatings. The results can be used to predict the functional characteristics of the mechanisms during their design.
Development of Fire Information Integration Application Platform
Authors: Chen Ching-Shun , Ho Yu-Tsung , Chen Yi-Lin , Chou Chung-Chyi 
Published: February 2020

Abstract
The aging society is a challenge facing all countries in the world. The collection and analysis of fire information in elderly care institutions has become a key factor in seeking shelter time. This study will build a fire information platform and its reporting mechanism through HTML, PHP, MySQL and other software development tools, and through the source and distribution of fire information. Public announce technology to improve the fire response capacity of the elderly institutions. This paper quotes Marchant (1980), a British scholar, who regards fire and refuge action as the parameters of elderly people’s refuge. The system of fire information platform consists of three parts: the “manager interface”, “cloud database” and “fire information platform”. The results show that the fire information reported after the confirmation of the management personnel can improve the residents’ confidence in the source of the information. The test results in the experimental field show that the higher the integrity of fire information content and the more rigorous distribution process are, the more helpful it is to shorten the judgment time of pre-avoidance tragedy, and the visual fire information platform is helpful to the correct judgment of the refuge route. Adding a call button to the platform can also increase residents’ sense of security. Fire information integration platform can help elderly care institutions take immediate shelter action in case of fire.
Use of Galactose Oxidase in Hydrazide-Capturing Technique to Isolate N-linked Glycoallergens from Olive Tree Pollen
Authors: Napoli A. 
Published: February 2020

Abstract
In this work, a simple method hydrazide-capturing technique followed by MALDI MS and MS/MS analysis for characterization of major pollen allergens of Olea europaea pollen was exploited. The strategy developed has different stages: devising of sample preparation protocol to sequester glycoproteins from a crude extract, and allowing the identification of antigenic peptides, glycosylation sites and modified glycans by MALDI MS and MS/MS.
Research on Aerial View Point Planning of Drone based on Multi-View
Authors: Yan-yan Shi Yun Zhu 
Published: February 2020

Abstract
For multi-view viewpoint planning research, Firstly, using the UAV aerial multi-view image, the viewpoint view is first to establish a candidate view area according to the shooting distance. Secondly, the sub-viewpoint set is filtered and the view points are complemented by the region where the candidate view cannot be photographed, so that the three-dimensional reconstruction data has better integrity. Thirdly, the influence of camera incident angle on image pixel error is analyzed, and the corresponding 3D model is established. Finally, the stereoscopic overlap is used to perform viewpoint screening under the premise of ensuring image quality and shooting coverage. The experimental results show that the proposed viewpoint planning method has high coverage and the reconstruction accuracy is below 0.1% of the target size.
A Simple Modification of HLLEM Approximate Riemann Solver Applied to the Compressible Euler System at Low Mach Number
Authors: Yu Hang , Li Hua , Lai Jianqi , Zhang Ye 
Published: February 2020

Abstract
Due to its attractive properties in computing compressible flows, such as sharp capturing of discontinuities, satisfying entropy condition and positivity preservation, the HLLEM approximate Riemann solver has been widely applied for simulations of many compressible flow problems. However, when it comes to weakly compressible or incompressible flows, the HLLEM scheme cannot give physically correct solutions. In the current study, a simple low Mach number fix is applied to improve the accuracy and stability of HLLEM approximate Riemann solver in the low Mach limit. As a result, a modified HLLEM scheme called LM-HLLEM scheme is proposed. Numerical results demonstrate that the proposed LM-HLLEM scheme is able to compute various flow problems accurately and robustly ranging from compressible to low Mach incompressible flows.
Effectiveness of Variable Rotor Blades Technique&Variable Stator Vanes Technique in AdjustingAxial-flow Compressor
Authors: Bingxiang Long , Qin Chen , Zebin Ren , Daxiong Liao 
Published: February 2020

Abstract
Multi-stage Axial-flow compressor is the main driver of continuous transonic wind tunnel and it usually has ultra-wide operating range. High performance wind tunnel generally requires its multi-stage axial-flow compressor has high economic performance and stability in its ultra-wide operating range. The combination of variable compressor rotational speed and variable geometry technique, variable rotor blades technique (VRBT) and variable stator vanes technique (VSVT), has been widely adopted in extending the stable working range with high efficiency of multi-stage axial-flow wind tunnel compressor. Adjusting Effectiveness was defined in this paper to quantify the effectiveness of VRBT and VSVT in extending stable and high aerodynamic efficiency operating range of wind tunnel axial-flow compressor under various operating conditions. The results show that the adjusting effectiveness of VRBT and VSVTis a function of reaction degree, flow coefficient, loading coefficient and the amount of loading coefficient change.
Modeling and Numerical Simulation of Stratospheric Aircraft Propulsion System
Authors: Yuan Xingjun , Wang Jiming , Tong Xuan , Wei Fengmei 
Published: February 2020

Abstract
Aiming at propulsion system of stratospheric, a high altitude propeller was designed. Avoiding the singularity of equations in the iterative process, the interference angle equation was improved and the designed propeller was calculated by the strip theory. The three-dimensionalNavier-Stokes equations were used to simulate the complex flow around the designed propeller and its aerodynamic characteristics were analyzed, in which the k-ω turbulence model was used. The accuracy of the numerical simulation was determined by the calculation of different grid numbers. The results show that the designed propeller can satisfy the requirement of propulsion system and the strip theory and numerical simulation can provide the reference for the design of stratospheric propeller.
Fluid-structure Interactions on Steerable Cruciform Parachute Inflation Dynamics
Authors: Gao Xinglong , Zhang Qingbin , Chen Qin , Wang Wenkai 
Published: February 2020

Abstract
To develop the decelerating and rigging potential performances of cruciform parachute during to its relatively large stand-off with lower cost production in precision aerial delivery operations, the fluid structure interaction behaviours of steerable cruciform parachute is studied. The concept of suspension lines control of cruciform parachute is firstly proposed. Based on the multi-material Arbitrary Lagrange-Euler method, the coupling dynamic model between a viscous incompressible fluid and a flexible large deformation structure of the cruciform parachute is solved. The inflation performance of a cruciform parachute under different steerable conditions is analysed. The decelerating parameters of the parachute, including drag area, and opening loads are obtained from FSI simulation. Meanwhile, the evolution of the three-dimensional shape of the cruciform parachute inflation is predicted.
Research on FMEA Application in Assembly Process of Complex Space Probes
Authors: Wang Chenxing , Feng Wei , Wang Linzheng , Song Song 
Published: February 2020

Abstract
The process of developing new spacecraft is time-consuming and task-intensive. This paper analyses various problems existing in the application of spacecraft FMEA, and points out that it is necessary to it is necessary to assure the validity of FMEA work, including normative FMEA work carried out in time, comprehensive identification of failure modes and their causes, correct expression of failure modes and their causes and effects, and the pertinence and maneuverability of measures to be taken. Taking the development of Mars rover as an example and considering the actual situation, the assembly process and FMEA agreement are proposed and formulated. According to the development process, the failure modes, causes and effects (severity) of the main processes are analyzed. The risk sequence number (RPN) is obtained by combining the frequency of occurrence and the difficulty of detection. Finally, through sorting out the assembly work and key points in each stage of AIT, 60 processes and 95 failure modes are analyzed, the possible weaknesses are found out, and the control methods and measures are put forward, so that the RPN values are below 12. Improve the quality and efficiency of product development by strengthening FMEA management, and ensure the smooth development of Mars probe on.
VISHKIRA, A Gallinaceous Aircraft
Authors: Taneja K , Jaiswal R , Kalwala S K 
Published: February 2020

Abstract
A Vishkira is an idea of a gallinaceous aircraft useful for military purposes. It is the modest version of morphing of wings and Ornithopter. This aircraft can morph itself by decreasing its span length by folding mechanism and locked at the folded position by electro-magnetism. The folded mechanism in wings uses electro hydraulics. This provides the flexibility to pass through narrow passages between mountains avoiding the aircraft to tilt and accomplish the military mission and also have an advantage of flying like a bird by flapping its wing as in Ornithopter producing a huge amount of thrust in a single flap of the wing. This provides a convenience of having a shorter runway which is suitable for military aircrafts when they are in a need of emergency take-off.
Research on Civil Aircraft Emergency Evacuation Time for Ditching
Authors: Yang Wu 
Published: February 2020

Abstract
Emergency evacuation for ditching is an important airworthiness requirement for civil aircraft to ensure safety. However, to demonstrate the emergency evacuation for ditching of a real aircraft is a time-consuming and laborious test with significant safety risks. Based on the analysis of airworthiness clauses, this paper proposes a method for calculating and analysing the emergency evacuation time for ditching. Taking a certain type of aircraft as an example, a typical case is selected for calculation and analysis, and the evacuation time under this typical case is obtained, which provides data support for the airworthiness emergency evacuation airworthiness compliance.