bluuebunny/crossref_metadata_2025_split huggingface dataset:
Investigation into detonation properties of PS-2 ammonium-nitrate-based granulite of different producers
Authors: Flyagin AS , Menshikov PV , Taranzhin SS 
Published: May 2021

Abstract
The comparative test results on PS-2 granulite based on porous ammonium nitrate (PAN) manufactured under TU 7276-004-17131060-2008 of different producers: Sibirsky Delovoy Soyuz Co. (Kemerovo), Akron Co. (Belikiy Novgorod), OHK Uralkhim Co. (Berezniki), NAK Azot Co (Novomoskovsk) are reported in the paper. The relationship of PS-2 granulite detonation velocity in steel pipes of 108 mm in diameter versus the grade of ammonium nitrate used is justified experimentally. DATATRAP II DATA/VOD Recorder is employed in the present research work.
Geomechanical conditions of extraction of gold-bearing ore reserves under the bottom of an open pit mine in Malomyr quartz deposit
Authors: Potapchuk MI , Kryukov VG , Saksin BG , Tsoi DI 
Published: May 2021

Abstract
Based on the studies into the engineering geology, geodynamic zoning, geomechanical stability and stress–strain behavior of rock mass, the authors substantiate the mining technology for Malomyr Mine.
Processing of high-clayed fine-gold-bearing sands
Authors: Shirman GV , Matveev AI , Matveev IA , Ermeeva NG , Ochosov OYu 
Published: May 2021

Abstract
Under consideration are the main causes for the fine and very fine gold loss in processing the alluvial high-clayed sands at conventional equipment. Scrubber-free washing plant, consisting of disintegration, classification, steeply-inclined and centrifugal–vibration concentrators is presented. The experimental research results on the most-recent washing plant justified the economic feasibility of this application.
Disintegration of geomaterials in ore pretreatment–The role and significance
Authors: Matveev AI , Lvov ES 
Published: May 2021

Abstract
It is shown that all ore pretreatment processes including the stages of crushing and grinding, depending on the structural and texture features of geomaterials, have two interconnected sides: destruction and disintegration. Disintegration is considered as a process of selective separation of geomaterials by their weakest bonds and as a process concomitant with mechanical destruction. The paper justifies the methodology for determining the degree of geomaterial disintegration by the example of impact crushing using grain size composition of crushed products. The proposed procedure is based on isolating the fraction of material that is predominantly accumulated in the form of a mode, which depends on the energy of mechanical effect that is responsible for the process of actual geomaterial destruction and is determined as a lognormal distribution. In this case, the degree of disintegration is determined by subtracting the fraction of geomaterial formed directly by mechanical destruction (in percent or unit fractions) from total distribution sum of grain size composition. Examples of calculating the degree of disintegration for some ore geomaterials are given. Assessing the degree of disintegration according to the developed procedure can become an important characteristic of ore pretreatment and operating performance factor of crushing and grinding devices.
Justification of electromagnetic scanning of oil-filled formation using downhole matrix antenna arrays
Authors: Khmelinin AP , Konurin AI , Konurina MI 
Published: May 2021

Abstract
An overview of methods for mapping disturbances in a rock mass is given on the example of determining hydraulic fracture systems in an oil-filled formation. Methods of passive and active microseismic monitoring, as well as electromagnetic examining of rock masses for the presence of inhomogeneities in it are considered. A promising option for the development of hydraulic fracture mapping systems is proposed - creation of downhole logging probes representing ground penetrating radars that implement the mode of electrical scanning of the rock mass under study. The calculation of downhole antenna array based on the Butler matrix is performed. The calculated parameters of a phased antenna array with a Butler matrix can be used to design a downhole logging probe for mapping hydraulic fractures, as well as for surveying engineering structures, for example, foundations of buildings.
Influences of alternative diesel fuels on tailpipe emissions and particulate matter under the highway fuel economy test cycle
Authors: Boontatao Phanuwat , Chuepeng Sathaporn 
Published: May 2021

Abstract
Diesel engine vehicles are widely used worldwide in community and goods transport sectors due to their engine’s high efficiency and durability. Despite continuous improvements in various aspects, the combustion of compression ignition in conventional diesel engine is yet an important source of pollution and particulate matter that causes issues to human health and the environment. The objective of this research work is to study the use of conventional diesel (B7), biodiesel (B10) and premium diesel (DHi) fuels that affects to the release of exhaust gas and particulate matter emissions from tailpipes during a Highway Fuel Economy Test (HWFET) cycle. The experimental results have shown that the combustion of B7 and B10 reduced particulate matter by 0.38% and 51.0%, reduced total unburned hydrocarbon by 25.3% and 28.3%, reduced carbon monoxide by 43.3% and 64.0%, and reduced nitric oxide by 6.0% and 16.5%, respectively compared to DHi baseline on mass basis. The vehicle running on B10 releases a higher particle concentration with a smaller size compared to DHi.
Physical and chemical characteristics of carbonized corncob through hydrothermal and pyrolysis conversion
Authors: Srilek Nongnoot , Aggarangsi Pruk 
Published: May 2021

Abstract
Thailand and south-east Asia have been struggled with agriculture biomass residues management for decades where open burning causes severe air pollution affecting millions of people every year. Thermal carbonization is one of the most cost-effective and environmentally friendly techniques which converted the low value residues such as straw, corn stovers and corncob into a more valuable material such as solid biofuel, chemical adsorbent feed stocks. This study aims to explore crucial characteristics of carbonized corncob including fibre composition, BET surface area and FT-IR spectrums. The characteristics can be used to identify the potential of the material for further surface enhancement or surface activation to produce the bio-based activated carbon. The carbonization process in this work includes mild temperature hydrothermal technique and high-temperature pyrolysis process. The hydrothermal carbonization temperature is set at 250°C in a pressurized reactor where a pyrolysis is operated at 480°C and 380°C at atmospheric pressure. The BET surface area of “hydrochared” corncob derived from hydrothermal is 11.53 compared with 16.13 m2 g−1 of the raw materials. The pyrolized biochar at 480°C and 380°C yields surface area of 7.66 and 6.12 m2 g−1. The oxygenated functional groups on char surface and BET surface area are also compared to provide baseline for carbon activation.
Design of small wind turbines to produce electricity for low wind speed in Thailand
Authors: Panyawong Suradet , Manosroi Woradej 
Published: May 2021

Abstract
This work studied the design of small Vertical Axis Wind Turbine (VAWT) S Shape and Leaf Shape which are appropriate for low wind speed in Thailand. The theory of Overlaps Ratio (β), End Plates and Blade Areas which effect to wind turbines operation were analysed. The turbines were tested in a wind tunnel and connected to permanent magnet generator under wind speed conditions close to the real wind speed. The starting up wind speed and Power Coefficient of Leaf Shape were 0.81 m/s and 0.011 and the starting up wind speed and Power Coefficient of S Shape were 0.63 m/s and 0.038, respectively. The results showed that the S-Shape performance was better than Leaf Shape. The results from this study can be applied for developing and improving the small turbine for the application at the low wind speed area in Thailand
Results of the measurement of SOFC fuel cell stacks under pressure conditions
Authors: Berg H.P. , Dückershoff R. , Vorpahl M. , Himmelberg A. 
Published: May 2021

Abstract
Results from the measurement of SOFC fuel cell stacks under pressure conditions are presented. As part of a measurement campaign, the operation of a stack system is investigated, particularly under the operating conditions of a recuperated micro gas turbine. Above all, the performance and effectiveness of selected stack types at various operating pressures and operating temperatures are measured. With the test facility set up for such investigations, cell systems could be examined under atmospheric conditions and with pressures of up to 5 bar.
It is shown that in operating conditions under pressure, the output of the fuel cell systems are improving. From a gauge pressure of 4 bar, the performance curve is flattened and higher pressures only produced a marginal increase in performance. Furthermore, the cells tested at overpressure show a steady-state behavior more quickly under load change requirements than in atmospheric operation. This means that more flexible operating modes with faster response behavior can be realized. By choosing a suitable operating temperature, the efficiency of the system is further increasing. Care was taken to select the operating conditions of the cell systems so that coking can be prevented.
Finally, a statement can be made about the pressure dependence of the fuel conversion rate. Parasitic reactions at the anode can be related to the power output. The tests carried out have shown that the high-temperature fuel cell is a promising service provider of the future. A combination of SOFC high-temperature fuel cells and micro gas turbines in one machine could, in addition to the internal provision of the required pressure, also lead to better dynamics of the entire system and increase the energy yield from the primary energy source.
Takeoff Performance Analysis of a Light Amphibious Airplane
Authors: Chinvorarat Sinchai , Watjatrakul Boonchai , Nimdum Pongsak , Sangpet Teerawat , Vallikul Pumyos 
Published: May 2021

Abstract
The performance analysis of a light amphibious airplane during takeoff from the water surface has been presented in this paper. The airplane is one of the light amphibious airplane series built in Thailand with a bi-wing configuration. The conceptual design aims to build a short takeoff and landing (STOL) amphibious airplane. The mathematical model cooperated with several complicated parameters is presented and solved by MATLAB. The water-drag resistance of the airplane is estimated from typical seaplane hull NASA technical information, which enhances the correctness of the model at takeoff configuration. The simulation reveals that the seaplane can successfully takeoff from calm water in 24.5 seconds at the speed of 54 KCAS and an approximate distance of 890 feet with the AOA of 10 degrees.
Investigation of loose contact oxidation kinetic analysis on diesel particulate filter’s wall surface using non-isothermal TGA technique
Authors: Zin Win Swe , Karin Preechar , Phairote Watanyoo , Chollacoop Nuwong , Saisirirat Peerawat , Hanamura Katsunori 
Published: May 2021

Abstract
Carbonaceous soot particles emitted from diesel engines are dangerous to human health because of its carcinogenic activity and can penetrate into lungs. In order to control soot emissions, diesel particulate filters (DPFs) are widely used to meet progessively stringent regulations of vehicle emissions limits. In this article, the characterization of conventional DPF microstructure was briefly investigated by scanning electron microscopy (SEM) addition with energy dispersive X-ray analysis (EDX) and X-ray fluorescence analysis (XRF). Non-isothermal oxidation mechanism of soot on conventional DPF was carried out from thermogravimetric analysis (TGA) under air atmosphere with the flow rate of 40ml/min at the heating rates of 5, 10, and 15°C/min. The kinetic parameters were calculated by three non-isothermal model-free methods. The average value of apparent activation energy obtained by Flynn-Wall-Ozawa (FWO), Kissinger-Akahira-Sunose (KAS) and Kissinger (K) were 77.02, 65.29 and 70.48 kJ/mol, respectively at different heating rates. The average results got from this work indicate that non-isothermal experiments were quite low compared to kinetics parameters estimated by the isothermal method from previous research.
Three-dimensional effects on the performance of multi-level overtopping wave energy converter
Authors: Jungrungruengtaworn S. , Thaweewat N. , Hyun B.S. 
Published: May 2021

Abstract
The performance of a multi-level overtopping wave energy converter has been numerically investigated in a three-dimensional wave tank. The device has three extra slots and is positioned on a breakwater. The span length of the breakwater is the main parameter associated with the three-dimensional effects on the hydraulic efficiency of the wave energy device. It has been shown that the device with a finite span yields a lower captured crest energy due to waves falling-down the edges during the run-up process. The result also implies that as the span of the device is increased, the efficiency tends to increase further to resemble the two-dimensional device. The three-dimensional mechanism has a significant influence on the potential energy in the water being stored by the higher reservoirs, while that of lower ones have relatively smaller effects. In addition, a relation between hydraulic efficiencies of two and three-dimensional devices has been proposed.
Effect of feed sprue size on porosity defects in Platinum 950 centrifugal investment casting via numerical modelling
Authors: Munpakdee K. , Ninpetch P. , Otarawanna S. , Canyook R. , Kowitwarangkul P. 
Published: May 2021

Abstract
The centrifugal investment casting process is typically used in the jewelry manufacturing industry. However, porosity defects are often found in jewelry castings made by this process. Porosity on the casting surface is a major concern for jewelry manufacturers as the defect leads to significant yield losses during the repair work. Improper feed sprue design is one of the major causes of porosity defects. The purpose of this work is to study the effect of feed sprue size on porosity defects in Platinum 950 jewelry made by the centrifugal investment casting process. Two feed sprue sizes were experimented in this study. FLOW-3D CAST software was employed for the casting process simulation. Simulation results were analysed together with experimental results quantified by an image analysis technique. The results show that the larger feed sprue provides castings with less porosity compared to the smaller feed sprue.
Steel fiber/polyethylene terephtalate composites
Authors: Duekhodthod Rossarin , Kitkamthorn Usanee , Mitsomwang Pusit , Intaing Tawatchai , Borrisutthekul Rattana 
Published: May 2021

Abstract
Currently, lightweight materials with high performance have been strongly needed to meet the requirements of advanced structural materials. One of the promising lightweight materials is the metals fiber reinforced plastic composite, which usually gives good specific strength and high toughness. However, de-bonding between metal fiber and plastic is the main problem in the production and utilization of the composite. Recently, Katayama, et., al. studied the dissimilar materials joining between plastics and metals such as PET/SUS 304 and so on. The joint was succeeded with the reaction between the metal oxide and functional group in the molecule of the polymer. The possibility to join metal/plastic may provide the new approach to produce new design composites. Thus, the objective of the study is to investigate the feasibility to produce stainless steel fiber reinforced PET plastics composite (SFRP). In experiments, stainless steel mesh and PET sheet with 0.5 mm of thickness were used as materials to fabricate the SFRP composite. The hot pressing of sandwich stacks with inserted SUS304 wire mesh between two PET sheets was performed at 120°C. Results indicated that high strength composite without de-bonding could be obtained.
Sintered 316L/Cu/h-BN composites
Authors: Chusong E. , Kansuwan P. , Khosakul R. , Ohtake N. , Wila P. , Tosangthum N. , Vetayanugul B. , Tongsri R. 
Published: May 2021

AbstractSintered 316L/h-BN composites show high potential as self-lubricating materials, which can be applied as moving parts where lube oils and greases are not applicable and inaccessible for maintenance. The past production of such composites by sintering, faced two problems. Firstly - interaction between 316L matrix and h-BN resulting in loss of h-BN content and its lubricity. And secondly - poor 316L matrix integrity. This work employed two approaches to solve such problems. The first approach was the use of nitrogen-containing atmosphere for sintering, to retard 316L matrix and h-BN interaction. And the second approach, was copper addition to promote sintering of 316L powder particles. Sintered self-lubricating 316L/Cu/h-BN composites were produced from mixtures of 3 different 316L/Cu matrices (made by additions of 2.0, 4.0 and 6.0 wt.% copper powder to 316L powder) and 15 vol.% of h-BN powder. Green compacts of powder mixtures were sintered under cracked ammonia (75 vol.% hydrogen + 25 vol. % nitrogen) at 1300°C for 60 minutes. The sintered composites were cooled in a Linn high temperature sintering furnace. It was found that copper additions led to the decrease of densities of sintered 316L/Cu/h-BN composites, compared to that of sintered 316L/h-BN composite, due to porosity left behind by copper powder melting and dissolution. Tensile strengths of sintered 316L/Cu/h-BN composites were improved when copper contents were 4 and 6 wt.%. There was no intergranular phase, the evidence of 316L matrix and h-BN interaction in all experimental sintered composites. Microstructural observation by scanning electron microscopy (SEM) also revealed that h-BN flakes still existed in pores of sintered composites. The unreacted h-BN flakes are expected to provide lubricity of sintered composites.
Effects of the environment on thermo physiological responses via 3D human eye model with porous media heat transfer theory under inconstant solar irradiation
Authors: Chawengwanicha P. , Rattanadecho P. , Keangin P. 
Published: May 2021

Abstract
The human eye is one of the most sensitive parts of our entire body. The lens is an important component of the eye, and it also plays an important role in vision. A lens has a normal temperature below 38.5°C. Thermal effects with solar irradiation result in the temperature of the lens to increase to more than 38.5 °C and may significantly influence the thermal physiologic response which, in turn, will cause the of deterioration of the lens. Therefore, investigation to get knowledge and guidelines to avoid thermal effects from the environment with solar irradiation, will help prevent the eyes from deterioration. However, the study of invasion, within the human body is impracticable. The study of environmental effects on thermo physiological responses within the human eye, from numerical analysis, is another alternative that is gaining attention worldwide. The purpose of this research is to learn about thermal physiologic response on human eyes exposed to solar irradiation, using the three-dimensional (3D) model by finite element method (FEM) via a computer program. This study uses the heat transfer equation and the Navier-Stroke equation to describe heat transfer phenomena in porous mediums and fluid flow phenomena within the 3D human eye model, based on considering the natural convection heat transfer of aqueous humor and vitreous humor, under inconstant solar irradiation. The effects of the environmental parameters such as ambient temperature and air convection heat transfer coefficient are investigated. The results show that the case study which makes the best cooling mechanism is the effect of ambient temperature with ambient temperature at 25°C and effect of air convection heat transfer coefficient at 40 W/m2·K that the eye can absorb maximum solar irradiance at 575 W/m2 at the lens reaches 38.5°C and the worst cooling mechanism is the effect of ambient temperature with ambient temperature at 35°C that the eye can absorb maximum solar irradiance at 360 W/m2 at the lens reaches 38.5°C. The results from this study provide the essential aspects for a fundamental understanding of thermal physiologic response within human eye subjected to solar irradiation.
Assessment of turbulence models for low turbulent natural convection heat transfer in rectangular enclosed cavity using OpenFOAM
Authors: Loksupapaiboon Kittipos , Suvanjumrat Chakrit 
Published: May 2021

Abstract
This research aimed to study two-equation turbulence models, for the simulation of low turbulent natural convection heat transfer, which happened in a rectangular enclosure. These models include k–ɛ, k–ω, RNG k–ɛ, k–ω SST and Realizable k–ɛ which are two-equation turbulence models in OpenFOAM. The simulation was carried out to compare against experiment in literatures which gave a Rayleigh number (Ra) of 1.58×109. The 3D cell structure by the 50×50×100 cells for the rectangular enclosure dimensions of 0.75 m (width)×0.75 m (height)×1.50 m (length) was modeled. It gave the large y+ of 30 but was still in the initial sub-layer. It was found that the k–ω model provided the best prediction of turbulent natural convection heat transfer. The standard k and ω wall functions were carried out to simulate well with the k–ω model. It was good modeling technique which the fine cells were not necessary to define nearly enclosure walls.
Numerical simulation of flow over a passive disturbance and backward-facing step
Authors: Loksupapaiboon Kittipos , Suvanjumrat Chakrit 
Published: May 2021

Abstract
This research aimed to simulate the flow past a rib and backward-facing step (BFS). The Reynolds and sub-grid-scale (SGS) stresses were modelled. These models consisted of k–ɛ, Smagorinksy-Lilly, SGS turbulence kinetic energy (kSGS
), dynamic SGS and wall-adapting local eddy-viscosity (WALE) which implemented in Open FOAM. The simulation was carried out to compare against the experiment in literatures which gave a high Reynolds number of 15,500. The simulation results showed that the k–ɛ model provided the best prediction of the turbulent flow over a passive disturbance and BFS. The absence of rib was carried out to compare with the presence of the rib. It was found that the rib positions had affected to flow reattachment behind the BFS.
Effect of interference on the press fitting of railway wheel and axle assemblies
Authors: Nwe Theingi , Pimsarn Monsak 
Published: May 2021

Abstract
Press fitting is one of the common fastening methods used to assemble mechanical components. It has also received considerable critical many industrial applications, for example, railway wheel and axle are usually assembled by press-fitting. This process generates high stress on the axle-fillet area and fatigue is generally initiated due to the stress concentration. This paper attempts to propose the stress distribution and deformation of a railway axle. Various interference clearances were analyzed using finite element method. The contact pressure at the axle wheel seat along the axial direction was examined as it significantly influences the press-fitted components life. The analytical results from Lame’s theory [1] were compared with finite element analysis results for the wheel and axle press-fitting process. The results obtained from both methods were in good agreement and the maximum relative error of the contact pressure is by 11.08 %. Additionally, the results show that the Von-Mises stresses on the axle wheel seat and fillet areas were found to be increased if the interference increased.