bluuebunny/crossref_metadata_2025 huggingface dataset:
Experimental investigations of friction stir welded AA6063 aluminum matrix composite
Authors: Kaushik Narinder , Singhal Sandeep , Rajesh Rajesh , Gahlot Pardeep , Tripathi B. N
Published: July 2020

The advancement of friction stir welding for joining of aluminum alloys and aluminum centered matrix composite has replaced the traditional welding techniques. In this experimental study, AA6063/10.5wt%SiC composite has been produced by employing enhanced stir casting technique with the assistance of Mg metal powder. Specimen composite plates having thickness 6 mm were friction stir welded successfully. The impact of welding variables on mechanical and microstructural characteristics of weldments has been studied. The friction stir welding (FSW) was carried out at a rotation rate of tool of 1400 rpm with a tool transverse rate of 124 mm/min. A cylindrical tool fabricated of high-speed steel (HSS) with square pin shape has been used for FSW. The results revealed that the ultimate tensile strength of the welded joint was 163 MPa, which was very close to the strength of the as-cast composite matrix. The microstructural study showed the reason for higher joint strength and microhardness. The welded butt joint exhibited a change in the microstructure at various four welding zones which transforms the mechanical characteristics of welded joints has been due to the asymmetrical flow of material and thermal cycles around the pin. The intense stirring action of the tool pin during FSW cracked the SiC particles in the weld nugget.  In the weld region, a fine-grained structure and homogeneous dispersion of SiC particles have been observed. The micro porosities associated with the base metal composite matrix were eliminated after FSW.
Effect of end chills, reinforcement content and carburization on the hardness of LM25-borosilicate glass particulate composite
Authors: Hiremath A. , Amar Murthy A. , Pranavathmaja S. V. , Jajodia A. , Sreenath R.
Published: July 2020

Aluminium metal matrix composites (AMCs) are widely employed in aerospace and automobile applications. Thus, they are required to operate reliably under a severe corrosive, high temperature and carbonaceous environments, without undergoing any deterioration in their mechanical properties. The paper is the compilation of the experimental results and analysis carried out to investigate the effect of different end chills, reinforcement content and carburization on the LM25 aluminium alloy reinforced with borosilicate glass powder. The composites are prepared via stir casting route by varying the weight percent (wt.%) of the reinforcement starting from 3 wt.% and going up till 12 wt.% with an increment of 3wt.% in every step. To obtain quality castings, end chills are placed within the sand mould. The specimens drawn from the chill-end of the castings are pack carburized in a muffle furnace for a set duration of time. The hardness of the specimens before and after carburization is recorded. The analysis of the results illustrates that the hardness increases linearly with the increase in the reinforcement content within the matrix from 3 wt.% up to 9 wt.%. It is also evident that the Volumetric Heat Capacities (VHC) of the chill material bears a strong effect not only on the quality of the castings produced but also on the hardness of the AMCs. Carburization leads to carbon deposition on the surface causing a change in the hardness of the specimens.
Fluid – structure interaction study for the DIFIS System’s composite riser tube
Authors: Fanourgakis S. D. , Mazarakos D. E. , Kostopoulos V.
Published: July 2020

DIFIS System was developed for oil recovery from shipwrecks and for the elimination of the pollution threat during EU FP-6 framework. The installation time’s reduction in cases of environmental pollution is a crucial factor for DIFIS system design. In the current work, the polyethylene riser tube parts (15 meter) of DIFIS System was replaced by a composite riser tube parts (30 meter) succeeding lower installation time for the DIFIS’s riser. The analysis and development of composite riser was based on the verified 2 – way fluid structure interaction (FSI) results from polyethylene riser. A methodology based on polyethylene riser’s normal modes (target values) was proposed and the composite riser’s structural integrity was investigated in order to reach these target values. The normal modes analysis and the 2 – way fluid structure interaction simulation were performed in ABAQUS software. The composite riser’s dynamic response under sea current is significant better than polyethylene riser (lower displacements in both axes, parallel and vertical to flow). In overall, the time reduction of the DIFIS’ risers installation by 40% was achieved, using longer riser parts.
Economic potential assessment of rare earth extraction sequence based on rule-based framework
Authors: M. Yunus M. Y. , Ismail N. A. , A. Aziz B.
Published: July 2020

Rare Earth Element (REE) is a unique group of metals which mainly comprises seventeen (17) elements, which fifteen (15) elements from the lanthanides group plus Scandium and Yttrium. This REE can be divided into heavy rare earth element (HREE) and light rare earth element (LREE) categories. During the initial extraction stage, the LREE is separated from HREE of the original ore and the sub-separations are then conducted subsequently corresponding to the respective categories. However, the separation difficulty becomes rather critical in a certain context, whenever the HREE is the major element to be extracted relative to LREE. In addition, there are no systematic guidelines procedures available to determine which specific separation pathway is more economically feasible among the various extraction options that exist. Thus, this study proposes a systematic quantitative rule-based framework, by excel modelling, in assessing comprehensively the economic potential of any separation model of REE processing that considered, whereby the standard characterization of monazite mineral composition is utilized as the main case study. This work also adopts the separation factor value of HDEHP-HCL as well as EHEHPA-HCL as the main extraction platforms. The findings suggest that the former extractant is effective for the extraction of light REE (LREE), while the latter incline to prefer the medium and heavy REE (MREE and HREE) particularly on the ground of separation stages factor. In light of the initial results, this study also proposes a hybrid approach in performing the complete optimal REE separation that specifically based on the sequence of ‘Art versus Science’ (AvsS) structure. These results have demonstrated that the proposed quantitative rule-based framework able to determine the optimal separation pathway provided the complete separation factor values and the mineral characterization of REE are available for assessment. Thus, this new method is suitably applied as a tool or guidelines in the feasibility study of any processing design for REE separation.
Multi-pass friction stirred clad welding of dissimilar joined AA6061 aluminium alloy and brass
Authors: Osman Nora , Sajuri Zainuddin , Omar Mohd Zaidi
Published: July 2020

Tool steels are commonly used to cut metal materials due to their distinctive hardness, resistance to abrasion and deformation. However, tool steels are difficult to be joined using conventional fusion welding process. In this study, a thixotropic property of metal was utilised to butt-join an AISI D2 tool steel by using uncommon direct partial re-melting (DPRM) method. A high frequency of induction heating is used to apply the DPRM method. From the recent study, there are many methods in achieving the globular microstructure with the success of semi-solid joining process. Though, very less information on the microstructural effect of semi-solid joining on the mechanical properties was reported. This study aims to analyse the effect of uniaxial force on the microstructural evolution and mechanical properties of the thixo-joint of D2 tool steel. The microstructural analysis showed the diffusion occurred between the grains of the thixo-joint sample with 2.5 N uniaxial force. The maximum strength of the thixo-joint sample with force was 652 MPa. This was slightly higher than the as-received sample and the thixo-joint sample without force. The average hardness value of the thixo-joint sample was 400 HV due to the transformation of ferrite to the metastable austenite.
Mechanical characterization of heat treated Al2219 hybrid composites
Authors: M. C. Gowrishankar , Sharma Sathyashankara , Pavan B. K. , Kiran Kamath , Rajendra Kumar , Hiremath Pavan , Shettar Manjunath
Published: July 2020

Aluminium alloy matrix composites with Al2O3 reinforcements exhibit superior mechanical properties and utilize in several demanding fields’ viz., automobile, aerospace, defense, sports equipment, electronics and bio-medical. The present work emphasizes on improvement of microstructure and mechanical properties of age hardened graphite and alumina reinforced Al alloy matrix hybrid composites. Different composites with a constant carbon content of 1 weight % and 0, 2, 4 and 6 weight % Al2O3 as reinforcements are fabricated by using stir casting technic and tested for hardness, tensile and impact strength. Scanning electron microscopy (SEM) is performed to analyse the failure mode under tensile load. All the composites are subjected to age hardening treatment with solutionising temperature of 530oC and aging temperatures of 100 and 200oC. The peak hardness of the composites at two aging temperatures are noted. Tensile and impact tests are conducted for the peak aged specimens.  Results show substantial increase in the hardness of the age hardened specimens in the range of 34-44% in comparison with the as cast specimens. Result analysis shows increase in tensile strength (upto 40%) and decrease in impact resistance (upto 33%) with the increase in weight % of reinforcements. As the aging temperature increases a reduction in tensile strength and impact resistance is observed in each composites.
Fuel as secondary refrigerant on LPG fuelled vehicle: A thermodynamics analysis
Authors: Setiyo Muji , Waluyo B.
Published: July 2020

In LPG-fueled vehicles, there is a potential cooling from LPG evaporation in the fuel line. Cooling power is obtained without reducing the caloric value of the fuel supplied to the engine. Thus, LPG functions like a refrigerant before it is burned in the combustion chamber. Consequently, there is a change in fuel efficiency. Therefore, this paper presents a new thermodynamic analysis on LPG-fueled vehicles by harvesting cooling power in the fuel line. The total fuel efficiency is calculated by summing the indicated thermal power added by cooling power to the fuel energy supplied. The results show that the A/C system from the fuel line can increase the total fuel efficiency of 3.16%.
Evaluation of induced residual stresses on AISI 1020 low carbon steel plate from experimental and FEM approach during TIG welding process
Authors: Owunna I. B. , Ikpe A. E.
Published: July 2020

Induced residual stresses on AISI 1020 low carbon steel plate during Tungsten Inert Gas (TIG) welding process was evaluated in this study using experimental and Finite Element Method (FEM). The temperature range measured from the welding experimentation was 251°C-423°C, while the temperature range measured from the FEM was 230°C-563°C; whereas, the residual stress range measured from the welding experimentation was 144MPa-402Mpa, while the residual range measured from the FEM was 233-477MPa respectively. Comparing the temperature and stress results obtained from both methods, it was observed that the range of temperature and residual stresses measured were not exactly the same due to the principles at which both methods operate but disparities between the methods were not outrageous. However, these values can be fed back to optimization tools to obtain optimal parameters for best practices.  Results of the induced stress distribution was created from a static study where the thermal results were used as loading conditions and it was observed that the temperature increased as the von-Mises stress increased, indicating that induced stresses in welded component may hamper the longevity of such component in service condition. Hence, post-weld heat treatment is imperative in order to stress relieve metals after welding operation and improve their service life.
Analysis of wind energy potential and wind energy development to evaluate performance of wind turbine installation in Bali, Indonesia
Authors: Satwika Nyoman Ade , Hantoro R. , Septyaningrum E. , Mahmashani A. W.
Published: July 2020

In recent years, Wind power generation in Indonesia is no longer a new issue. Indonesia has average velocity from 2 m/s  to 7 m/s. With the characteristic it, Indonesia is suitable for small (10 kW) and medium wind turbine installation (10-100 kW. Based on the monitoring data from meteorological, climatological, and geophysical agency (BMKG), the average wind velocity in Bali is 2 m/s – 5m/s, hence Bali has potential to development and utilization the source for wind turbine installation, There are four stations of BMKG in Bali, which each station is supervise the region. Weibull distribution has been represented on this research to calculate and determine the probability of the each of region to know the availibility of the source. Literally,  Jembrana station has the lowest availability of power available from the district and cities in Bali, with 0-0.2 W/m2, compared with some districts and cities in Bali, with wind density power between 0-2.88 W/m2 and also the KHK station has the highest probabiity of wind velocity than the other regions. Reconstruction design had been done, with basic data from probability in Bali. The result shows that the redesign of wind turbine give an effective power to extract the wind source.
An investigation into tapping of Al6061/SiC metal matrix composite with straight flute HSS machine tap
Authors: . Nagaraja , Adhikari Raviraja , Yasir T.
Published: July 2020

The present study deals with tapping of Al6061/SiC metal matrix composite. Stir casting technique was used for the fabrication of composite. Castings were produced by varying weight percentages of SiC (5%, 7.5% and 10%) of 23μm size in Al6061. The tapping experiments were conducted for the machinability study of Al6061/SiC metal matrix composite using M8 x 1.25 HSS machine taps. The tapping operation was performed under dry condition with different cutting speeds. Torque required for tapping was measured using piezoelectric based 4-component drill tool dynamometer. Surface morphology and profile of thread surfaces were analysed using Scanning Electron Microscope (SEM) and metallurgical microscope. Estimation of progressive flank wear of machine taps was undertaken using profile projector. The performance of HSS machine tap was evaluated in terms of tapping torque, tool flank wear, and surface characteristics of thread surfaces. The flank wear of uncoated HSS machine tap increased with the increase in weight percentage of SiC in Al/SiC composite for a particular cutting speed. Further, when the matrix materials were reinforced by the same kind and the same weight percentage of SiC particles, the flank wear of the tool was found to increase with cutting speed. In addition, the damage caused to thread profiles increased with the increase in cutting speed and weight percentage of SiC.
Effect of sintering temperature on density, hardness and tool wear for alumina-zirconia cutting tool
Authors: Hadzley A. B. , Norfauzi T. , A. Umar U. A. , Afuza A. A. , M. Faiz M. , Naim M. F.
Published: July 2020

Combination of alumina (Al2O3) and zirconia (ZrO2) as cutting tool have been established themselves as a dominant in ceramic category for dry machining. The mechanical properties of Al2O3-ZrO2 cutting tool were critically dependent on its density and hardness, which affected by the powder preparation and sintering processes. This paper present the effect of sintering temperature on density, hardness and tool wear of Al2O3-ZrO2 cutting tool. Specific composition of 80-90 wt% Al2O3 and 10-20 wt% ZrO2 powders were mixed and ball milled for 12 hours. These powders then were compacted in the form of RNGN120600 designated cutting tool by using manual hydraulic press before undergone secondary compaction by Cold Isostatic Press. The compacted powders then were sintered from 1200oC to 1400oC at constant 9 hours soaking time. For each sintered cutting tool, evaluation has been made based on the density and hardness. By using AISI 1045 as a workpiece material, the wear performance of the selected cutting tools were evaluated within 200-350 m/min cutting speeds, 0.1 mm/rev feed rate and 0.5 mm depth of cut. The results shows that the sintering temperature at 1400oC and 9 hours soaking time produced maximum relative density and hardness for 90 wt% Al2O3 and 10 wt% ZrO2 at 94.17% and 63.4 HRC respectively. Cutting tool contained with 80 wt% Al2O3 and 20 wt% ZrO2 contributed maximum relative density of 97% and hardness of 70.07 HRC. Maximum tool life recorded was 156s at 200 m/min cutting speed. Wear mechanisms of fabricated cutting tool dominated by the notch and flank wear at the early stage of machining and formation built up edge at the end of machining process.
A comprehensive study on the buckling behaviour of woven composite plates with major aerospace cutouts under uniaxial loading
Authors: Rayhan S. B.
Published: July 2020

Current research paper presents a comprehensive study based on Finite Element Method (FEM) to understand the effect of cutout shape and area on the buckling behaviour of E-glass composite plates. Considered plate has a dimension of 150 mm × 75mm × 3mm where loading edges are simple supported (shorter side) and other two edges are free. Major aerospace cutout shapes i.e. circular, square, elliptical (horizontal and vertical) and diamond are studied to understand their effect on plates’ critical buckling load. FE code Ansys is adopted to investigate the case studies. A limited number of experimental tests are also carried out in order to validate the FE code results. Overall, a good agreement between experimental and FE code results are found. From finite element analyses, it is found that for any cutout shape, as the cutout area increases, buckling load decreases significantly. Moreover, increasing the plate thickness by 0.5 mm can raise the buckling load up to 50%. More importantly, fibre orientation angle has most significant effect on the critical buckling load of plates where fibre orientation aligned with loading direction can increase the plates’ critical buckling load from 2.6 to 2.8 times than aligned with 900.
Effect of solution treatment on the microstructure and mechanical properties of Ti-6Al-6Mo hot-rolled alloy
Authors: . Alfirano , Friandani S. S. , Sutowo C.
Published: July 2020

Titanium and its alloys are widely used in biomedical applications due to their unique combination of good hot workability, high specific strength and good corrosion resistance. In this study, elastic modulus, hardness and the effects of solution treatment on microstructures and mechanical properties of Ti-6Al-6Mo hot-treated alloy were investigated using OM (optical microscopy), XRD (X-ray diffractometry), SEM (Scanning electron microscopy), Ultrasonic testing and hardness testing. Previously, the sampels were hot-rolled at 900oC for 1 h with a total reduction of 50%,and then followed by air cooling. The samples were carried out solution treatment for 1 h at 850oC and 950oC, followed by water cooling and at temperature of 1050oC with water and air cooling. The results indicate that the hardness of the Ti-6Al-6Mo alloy increased with the increasing of solution treatment temperature on the water cooling, while the elastic modulus was decreased. The lowest elasticity modulus value and the highest hardness, 125.4 GPa and 46.3 RC were obtained at 1050oC with equiaxed micro structure and β' precipitate. XRD analysis exhibited the presence of α and β phases in Ti-6Al-6Mo alloys after solution treatment. Based on the relative intensity of XRD strongest peak analysis, the α phase intensity decreases with the increasing of solution treatment temperature, this phenomenon causes the decreasing of elasticity modulus value with the increasing of solution treatment temperature on water cooling medium.
Thermal study of fluid flow inside an annular pipe filled with porous media under local thermal non-equilibrium condition
Authors: Bouaffane Abdelkrim , Talbi Kamel
Published: July 2020

The present work involves the thermal numerical simulation of fluid flow inside an annular pipe completely filled porous material. The mathematical model of the energy transport is based on the Local Thermal Non-Equilibrium (LTNE) between the fluid and the solid phases. The governing equations are discretized by the finite volume method. SIMPLE algorithm has been used to solve the set of algebraic discretized coupled equations. This work is divided in two parts. In the first part, the effect of the pertinent dimensionless parameters which govern the study such as Biot number (Bi), solid-fluid thermal conductivity ratio (Rc) and radius ratio (Rr) on the LTNE intensity are analyzed by calculating: the local difference of temperature (LDT), the maximum of the local difference of temperature (LDTmax) and the average of LDT. The results show that the increase of Biot number and the solid-fluid thermal conductivity ratio, and the decrease of radius ratio reduce the LTNE intensity. The intensity of the LTNE in the developing region is greater than that of the fully developed region. In the second part, the convection heat transfer enhancement is studied, the results illustrate that the increase of Biot number and the solid-fluid thermal conductivity ratio, and the decrease of radius ratio represent good factors to ameliorate the rate of the convection heat transfer between the fluid and the inner wall.
Optimization of physical and mechanical properties of glycerol - modified natural rubber/starch - filled carbon black composites using two level factorial design
Authors: Mazliah M. , Mohamad N. , Ab Maulod H. E. , Jeefferie A. R. , Mohd Abid M. A. A. , Karim K. I. , Mahamood M. A. , Hamdan M. M.
Published: July 2020

A statistical model was developed in this study to describe cure characteristic, rebound resilience and tensile strength of natural rubber/starch composites which was prepared by using a Haake internal mixer. Response surface methodology (RSM) based on central composite centered design (CCD) was employed to statistically evaluate and optimize the conditions for maximum cure characteristic, rebound resilience and tensile strength and study the significance and interaction of carbon black and glycerol on rebound resilience and tensile strength yield. The experimental runs were carried out according to a 22 full factorial design for the two identified design independent variables, namely, carbon black (X1) and glycerol (X2). With the use of the developed quadratic model equation, a maximum rebound resilience 71% was obtained to be a carbon black loading of 50 phr and glycerol loading of 7 %.
Fatigue crack analysis of ferrite material by acoustic emission technique
Authors: Khan Md. T. I. Islam , Rashid A. A. , Hidaka R. , Hattori N. , Islam Md. M.
Published: July 2020

Recently in various fields, numerous researches are going on for the assessment of material damage on the basis of crack initiation and propagation. Various methods are available in NDT for this purpose, among which analysis using released acoustic emission (AE) waves due to crack propagation is very effective due to its dynamic monitoring features. Various approaches are proposed for long time to make it an ideal method for accurate monitoring of crack behaviors in materials. In fragmentation theory there are some proportionality among the relations of AE event, AE energy, area and volume of cracks etc., which are calculated from the released AE waves from any dynamic crack. It has been found that the necessity of calculating the fractal dimension is important in verifying these relationships. This parameter is emphasized for determining the geometry of the irregularity in crack surface and crack volume. In this paper a novel approach based on image processing is proposed to find out the fractal dimension for analyzing the crack propagation characteristics. Finally, the proportionality relationships of AE parameters with crack propagation behavior in ferrite cast iron under fatigue loading are demonstrated experimentally.
A new type of magnetic pump with coupled mechanical vibration and electromagnetic force
Authors: Yaguchi Hiroyuki , Mishina Toshiki , Ishikawa Kazumi
Published: July 2020

There is a demand for intravenous drips for medical sites and for liquid delivery of microfluidic chips in the field of chemical analysis. Furthermore, in these chemical analysis and medical pumps, disposable is often required. In this paper, a new small size pump combining electromagnetic force and mechanical vibration was proposed. The small size pump of vibration type with an outer diameter of 19 mm and a height of 56 mm was prototyped, and the optimum design of the pump shape was carried out. In addition, by attaching an iron plate to the iron core of the electromagnet, a method of increasing the strength of the magnetic field at one pole of the electromagnet without changing the magnetic circuit was suggested. By the generation of an asymmetric magnetic field due to the addition of the iron material, the maximum efficiency of the pump was 10.7 %. This small size pump has a very simple structure and can deliver water to the pumping head exceeding 1000 mm.
Design and development of a modular vibration test rig for combination types of fault in rotating machinery health diagnosis
Authors: Silahuddin S. M. , Aizuddin A. M. , Mohamaddan S. , Syed Shazali S. T. , M. Suffian M. S. Z. , Tazuddin A. M. , Abdullah A. S.
Published: July 2020

As a basis to real application of rotating machineries operation, a test rig imitating the operation is designed for the research environment. The purpose of this study is to design a modular test rig which is able to facilitate different fault component combinations and evaluate the deformation pattern of the fabricated test rig. Rotating machineries face the probability of having simultaneous different faults and the study of this condition is limited. The designed test rig could be arranged into multiple configurations by adding or excluding desired components due to its modularity. This will be useful to study the response of each component during operation as well as the response of combinations of fault components. Included in this study is the analysis of the design, the components of the test rig and the final design as well as the experimental data results of the fabricated test rig. This test rig is beneficial for understanding the vibrational behavior of components especially in educational environment.
Optimal design of junctionless double gate vertical MOSFET using hybrid Taguchi-GRA with ANN prediction
Authors: Kaharudin K. E. , Salehuddin F. , M. Zain A. S. , Roslan Ameer F.
Published: July 2020

Random parameter variations have been an influential factor that deciding the performance of a metal-oxide-semiconductor field effect transistor (MOSFET), especially in nano-scale regime. Thus, controlling the variation of those parameters becomes extremely crucial in order to attain an acceptable performance of an ultra-small MOSFET. This paper proposes an approach to optimally design a n-type junctionless double-gate vertical MOSFET (n-JLDGVM) via hybrid Taguchi-grey relational analysis (GRA) with artificial neural networks (ANN) prediction. The device is designed using a combination of 2-D simulation tools (Silvaco) and hybrid Taguchi-GRA with a well-trained ANN prediction. The investigated device parameters consist of channel length (Lch), pillar thickness (Tp), channel doping (Nch) and source/drain doping (Nsd). The optimized design parameters of the device demonstrate a tolerable magnitude of on-state current (ION), off-state current (IOFF), on-off ratio, transconductance (gm), cut-off frequency (fT) and maximum oscillation frequency (fmax), measured at 2344.9 µA/µm, 2.53 pA/µm, 927 x 106, 4.78 mS/µm, 121.5 GHz and 2469 GHz respectively.
Thermal performance enhancement of flat plate solar air heater using transverse U-shaped turbulator - A numerical study
Authors: Manjunath M. S. , Venkatesh R. , Madhwesh N.
Published: July 2020

The aim of this study is to determine the effect of U-shaped rib turbulator on the flow and heat transfer characteristics of flat plate solar air heater using two dimensional CFD analysis. The analysis is carried out using the CFD software tool ANSYS Fluent for the flow Reynolds number ranging from 9000 to 21,000.The relative pitch(P/e) of the U-shaped rib is varied as 5, 10, 25 and 40 for a fixed relative rib height of 0.0421. It is shown that the U-shaped rib augments the Nusselt number by about 1.76 times while the friction factor increased by about 1.95 times with reference to smooth duct for a relative pitch of 10 and 5 respectively. The maximum thermal enhancement factor is obtained as 1.5 for the configuration of P/e=25. A comparative analysis of U-shaped rib with circular rib reveals that the U-shaped rib turbulator is found to be more effective in providing heat transfer enhancement and has about 15% higher thermal enhancement factor as compared to circular turbulator.
Bearing fault diagnosis employing Gabor and augmented architecture of convolutional neural network
Authors: Waziralilah N. Fathiah , Abu Aminudin , Lim M. H. , Quen Lee Kee , Elfakarany Ahmed
Published: July 2020

The vast impact on machinery that is rooted by bearing degradation thus pinpointing bearing fault diagnosis as indubitably very crucial. The research is innovated to diagnose the fault in bearing by implementing deep learning approach which is Convolutional Neural Network (CNN) that has superiority over image processing and pattern recognition. A novel model comprises of Gabor Transform and CNN is proposed whereby Gabor Transform is utilized in representing the raw vibration signals into its image representation. The CNN architecture is augmented for a better accuracy of the bearing fault diagnosis model. To date, the method combination has never been deployed in establishing fault diagnosis model. Plus, the usage of Gabor Transform in mechanical area especially in bearing fault diagnosis is meagrely reported. Scant researches in mechanical diagnosis are dedicated to work on the image representation of the vibration data whereas the CNN works better when fed by images input due to its unique strength of CNN in images processing and spatial awareness. At the end of the research, it is perceived that the proposed model comprises of Gabor Transform and CNN can diagnose the bearing faults with 100% accuracy and perform better than when CNN is fed with raw signals.
An Axiological Analysis of the Bylinas About Dunay and Potyk
Authors: Mironov Arseny S.
Published: July 2020

Based on an axiological analysis of the bylinas about Dunay Ivanovich and Mikhailo Potyk, the article reveals a number of epic motifs which are interpreted as a semantic unity of the hero’s motivation, his deed, and its consequences. The article brings to light how the epic singer renders the spiritual laws connecting the motivation for a certain act with its consequences (i.e., the hero’s punishment and his subsequent penance or perdition); and formulates cognitive ethical meanings belonging to each of the bylina’s motifs. For each motif, the author identifies the following components: the hero’s particular moral weakness or passion which captures him, evoking thus, sympathy — or the so-called «compassion» — in the listeners; the moment when the hero is overcome by his sin; the moment of the crime; and the punishment as a natural consequence of the hero’s deeds. Also, the difference between axiological coordinates of every act — before and after its commission, in the evaluation of either the hero or the listener — is determined in the present paper. The motifs of the mentioned bylinas are classified here on the basis of their type and their involvement into parallel structures with similar motifs, or by the presence — or absence — of their antithetical counterparts. The result of the present study is a denial of the widespread theory according to which Russian bylinas should be described as «meaningless», as having controversial diachronous semantics, as damaged — in terms of the content — during their existence in this or that social milieu (peasant, skomorokh, minstrel or Cossack one), as presupposing allegedly «extraneous» and «recent» Christian concepts and ideologemes.
Pushkin in Yuly Aykhenvald’s Philosophical and Aesthetic System
Authors: Takho-Godi Elena A.
Published: July 2020

The article raised the question of the role of the Pushkinian principle in the philosophical and aesthetic system of Yu. I. Aykhenvald, one of the leading critics of the Silver Age. The given review of Aykhenvald’s publications on Pushkin and Pushkin studies of the first quarter of the twentieth century and analysis of Aykhenvald’s attitude to V. G. Belinsky’s and D. S. Merezhkovsky’s statements about Pushkin allowed defining more clearly the position of the literator, his approaches and methods. Aykhenvald’s articles about Anna Akhmatova, V. Bryusov, I. Bunin demonstrate that the involvement in the Pushkin tradition was for Aykhenvald the most important aesthetic criterion in assessing the modern literary process. Besides, the article regards the question of perception of Pushkin’s studies of Aykhenvald by his contemporaries — writers (B. Zaitsev, B. Sadovskoy, V. Khodasevich), literary scholars (S. A. Vengerov, B. M. Eichenbaum, A. P. Skaftymov), cultural historians (P. M. Bicilli) and representatives of Russian religious philosophy (S. L. Frank, A. F. Losev). It is concluded that, in contrast to literary historians, the phenomenon of Aykhenvald was for philosophically minded admirers of his critical talent a confirmation of the unity of national culture, the irreducibility of the nation to nationality and Pushkin as its main symbol.
About the Utility of Russian Literature Outside of Russia
Authors: Giuliani Rita
Published: July 2020

This article analyzes the excellence, uniqueness and specific elements of Russian literature that make it valuable in the eyes of a Western reader, helping him or her to better understand Russia and enrich his or her spiritual dimension. There are many such elements, and while I cannot touch on all of them, I would like to remind the reader of the fact that Russian literature has always been that particular point where social, humanitarian, political and philosophical thought comes together. Russian literature also sheds light on the mindset of the Russian people (narod), offering a different perspective to a Western reader. In addition, Russian literature, with its cultural ‘explosions’ (vzryvy) and the writers who embodied these explosions, greatly influenced European literature, inspiring entire generations of readers and writers. What turned out to be most unique in Russian literature was a perpetual attention to the great questions of human existence, the so-called “damned questions” (proklyatye voprosy). But Russian literature has an additional quality, starting from that moment when its hero became the human soul. It is precisely the soul, the protagonist of Russian literature, which unites Russian writers in a unique and inimitable community, and their readers and admirers — in a community moved and grateful. Ultimately, Dostoevsky — probably the most beloved Russian writer in the West — was right when he asserted in his well-known Pushkin speech, “the capacity for universal compassion (otzyvchivost’) is the most important quality of our national character”.
Revisiting cognitive load theory: second thoughts and unaddressed questions
Authors: Leppink Jimmie
Published: July 2020

In cognitive load theory (CLT), learning is the development of cognitive schemas in a long-term memory with no known limits and can happen only if our limited working memory can process new information presented and the amount of information that does not contribute to learning is low. According to this theory, learning is optimal when instructional support is decreased going from worked examples via completion problem to autonomous problem solving and learners do not benefit from practicing retrieval with complex content. However, studies on productive failure and retrieval practice have provided clear evidence against these two guidelines. In this article, issues with CLT and research inspired by this theory, which remain largely ignored among cognitive load theorists but have likely contributed to these contradictory findings, are discussed. This article concludes that these issues should make us question the usefulness of CLT in health science education, medical education and other complex domains, and presents recommendations for both educational practice and future research on the matter.
Bibliographie zur äthiosemitischen und kuschitischen Sprachwissenschaft I
Authors: Voigt Rainer
Published: July 2020

Bibliography for the study of Ethiosemitic, Cushitic and Omotic languages.
Manoel Barradas: Tractatus Tres Historico-Geographici (1634). A Seventeenth Century Historical and Geographical Account of Tigray, Ethiopia
Authors: W. Aregay Merid
Published: July 2020

ReviewATTENTION: Due to copy-right no online publication is provided
The Evolution of Ethiopian Absolutism. The Genesis and the Making of the Fiscal Military State, 1696-1913
Authors: Tegenu Tsegaye
Published: July 2020

Dissertation AbstractATTENTION: Due to copy-right no online publication is provided
23.-25.10.1997 in Mainz (Deutschland): Saints, biographies and history in Africa
Authors: Böll Verena
Published: July 2020

Conference Report
12.-17.12.1997 in Kyoto (Japan): The XIIIth International Conference of Ethiopian Studies
Authors: Uhlig Siegbert
Published: July 2020

Conference Report
The Antiquities of Däbrä Zäyt Qǝddǝst Maryam (East Tǝgray, Ethiopia)
Authors: Nosnitsin Denis
Published: July 2020

The article summarizes the results of the research at Däbrä Zäyt, one of the historical sites discovered by the team of the project Ethio-SPARE (Hamburg University, Hiob Ludolf Centre for Ethiopian Studies) in Gulo Mäḵäda, East Təgray. It presents different types of historical evidence (old church building of the site, an inscription, the church library) and focuses on the analysis of the fragments of the so-called “old Golden Gospel” of Däbrä Zäyt, written presumably by the same scribe as the one of the well-known ms. Vat. Aeth. 25.
Indigenous Views on the Italian Occupation in Southern Ethiopia A Post-Colonial Approach
Authors: Braukämper Ulrich
Published: July 2020

The present focus on “postcolonial studies” in cultural anthropology is attributing a growing interest to the Italian occupation in Ethiopia (1935–1941). Whereas a considerable amount of “mainstream” information has been collected about the war of conquest and colonial rule by Fascist Italy, the indigenous views and attitudes at the grassroots of Ethiopian people have largely remained outside consideration. Because of the harsh exploitation by the ruling elites of the empire, large parts of the inhabitants in the south readily collaborated with the foreign occupants. Resistance against the Italians could most efficiently be counteracted by a policy of “divide and rule”. Although the effects of Italian occupation are a sensitive issue of research involving highly controversial views and emotions, it seems to be due time now to approach it in an unbiased scholarly discourse.
In memoriam Stanislaw Chojnacki (1951-2010)
Authors: Pankhurst Richard , Pankhurst Rita
Published: July 2020

Obituary
In memoriam Paul B. Henze (1924-2011)
Authors: Shinn David
Published: July 2020

Obituary
Maria Luisa Agati: Il libro manoscritto da Oriente a Occidente: Per una codicologia comparata
Authors: Bausi Alessandro
Published: July 2020

Review
Galina Alexandrovna Balaschova: Современная драматургия Эфиопии [Sovremennaja dramaturgija Efiopii, “Moderne dramatische Dichtung Äthiopiens”]
Authors: Zabolotskikh Maxim
Published: July 2020

Review
Volker Matthies: Unternehmen Magdala: Strafexpedition in Äthiopien
Authors: Meckelburg Alexander
Published: July 2020

Review
Word Order in Epigraphic Gǝ’ǝz
Authors: Bulakh Maria
Published: July 2020

The paper offers the results of analysis of word order throughout the epigraphic corpus of Gǝʿǝz. This evidence is mostly in agreement with the data from Classical Gǝʿǝz and confirms that early Gǝʿǝz represents the classical Semitic type of a right-branching language: objects and prepositional phrases mostly follow the verbs, and relative clauses and genitive complements usually follow the head nouns. At the same time, some differences between the syntax of Classical Gǝʿǝz and Epigraphic Gǝʿǝz have been registered, notably in the behaviour of numerals.
Verlust und Wiederauffindung äthiopischer Handschriften aus der Sammlung Rüppell
Authors: Tönnies Bernhard
Published: July 2020

This article deals with the loss of Ethiopian manuscripts in possession of the Universitätsbibliothek Frankfurt am Main (Sammlung Rüppell) during World War II and the rediscovery of two of these manuscripts in 2010.
Benyam Sisay Mendisu: Aspects of Koorete Verb Morphology
Authors: Schulze Michael
Published: July 2020

Review Article
Andreas Wetter: Das Argobba. Eine deskriptive Grammatik der Varietät von Shonke und T'ollaha (Zentraläthiopien)
Authors: Schulze Michael
Published: July 2020

Review Article
Mohammed Ali Al-Salami: Sabäische Inschriften aus dem Ḫawlān
Authors: Agostini Alessio
Published: July 2020

Review
Christine Chaillot: Vie et spiritualité des Eglises orthodoxes orientales des traditions, syriaque, arménienne, copte at éthiopienne
Authors: Ancel Stéphane
Published: July 2020

Review
Karl Johan Lundström - Ezra Gebermedhin: Kenisha: The Roots and Development of the Evangelical Church of Eritrea 1866-1935
Authors: Dege Sophia
Published: July 2020

Review
Ivo Stecker: Ethnographic Chiasmus: Essays on Culture, Conflict and Rhetoric
Authors: Braukämper Ulrich
Published: July 2020

Review
The Legitimising Project: The Coronation Rite and the Written Word
Authors: Orlowska Izabela
Published: July 2020

The article and its argument are based on a hitherto unexplored Ethiopian chronicle, which offers a uniquely detailed description of a series of enthronement rites. The article explores and deciphers symbolism displayed in these acts, which was drawn from the past and remodelled to form ideological underpinning for the monarchy of Yoḥannǝs IV (1872–89) and to legitimise his imperial project. The article argues that despite the fact that the record of these events is likely to have been ‘adjusted’ by Ethiopian chroniclers, their writings still points to what they thought should happen during a ritual in order for it to be effective. Consequently, the authors of the chronicle revealed to us the role of ritual in the legitimising project of late 19th-century Ethiopia.
On Visibility and Legitimisation of Languages: The ‘Linguistic Landscape’ in Adaama, Ethiopia
Authors: Wolff H. Ekkehard , Berhanu Sileshi , Fulea Getinet
Published: July 2020

With a focus on the city of Adaama (formerly: Nazret), the biggest urban agglomeration in Oromia Regional State, the paper addresses the “linguistic landscape” which is indicative of the overall sociolinguistic situation of a polity. Language use in the public space has not only practical-instrumental, but also historical, political, juridical, and most of allpsycho-sociological dimensions, the latter relating to the symbolic value of written language use. The paper deals with multilingual graphic representations on public commercial and private sign-boards, advertisements, and notices in Adaama city, with an additionalfocus on the situation on the campus of Adama Science and Technology University. Under the chosen theoretical framework, it analyses language visibility in terms of language legitimisation, both in terms of peoples’ attitudes and based on official documents regarding language status and language use in present-day Ethiopia, such as the Education and Training Policy (1994), the Constitution of the Federal Democratic Republic of Ethiopia (1995), the Revised Constitution of Oromia Regional State(2001/2006), and the Higher Education Proclamation (2009). The primary focus of the paper is on the status, functions, and representations of AfanOromo, including a review of the major historico-political changes affecting this language from Imperial Ethiopa (before 1974), the Därg period (until 1991), and under the new Constitution of the FDRE (since 1995). The paper also deals with linguistic and graphic issues concerning the “orthographic” representations of the four languages used: Afan Oromo, Amharic, Arabic, and English, involving three different graphic systems: Fidäl (Abugida), Arabic, and Roman.
Bibliographie zur äthiosemitischen und kuschitischen Sprachwissenschaft XVI: 2011
Authors: Voigt Rainer
Published: July 2020

Bibliography for the Study of Ethiosemitic, Cushitic and Omotic Languages.
ITYOPIS ኢትዮጲስ – Northeast African Journal of Social Sciences and Humanities, Vol. 1
Authors: Tafla Bairu
Published: July 2020

Review
Estelle Sohier: Le roi des rois et la photographie. Politique de l’image et pouvoir royal en Éthiopie sous le règne de Ménélik II
Authors: Ancel Stéphane
Published: July 2020

Review
Pino Schirripa (ed.): Health System, Sickness and Social Suffering in Mekelle (Tigray – Ethiopia)
Authors: Pili Eliana
Published: July 2020

Review
Snakes and Sacrifices: Tentative Insights into the Pre-Christian Ethiopian Religion
Authors: Manzo Andrea
Published: July 2020

Despite the recent efforts which were recently made in this field of study, our knowledge of the pre-Christian religion of Aksumite Northern Ethiopia remains very limited. This article presents the contribution that archaeology can make to debate on this topic. In particular, some archaeological finds from Betä Giyorgis, north of Aksum, and from Aksum itself which can be related to the cult of the snake and to the practice of human sacrifices are described. These finds, dating from the Proto-Aksumite (3rd–1st centuries B.C.) and the first part of the Aksumite (1st–4th centuries A.D.) periods, may support the reality of the cult of the snake and of the practice of human sacrifices, two elements characterizing the Ethiopian traditions related to Arwe, the mythic snake-king of Aksum. In the conclusions, these specific aspects which may have characterized the pre-Christian Ethiopian religion are put in a broader regional context, compared to what is known about similar cultic traits in the Nile valley, in the Near East, and in South Arabia. Possible links to be explored with further research covering the different traditions are suggested. Moreover, a possible evolution in the meaning of the snake in Ethiopia, from benevolent and helpful entity to dangerous monster, and, finally, to symbol of sin, is outlined.
Rim Transactions of liqe Bätre: A Preview of the Transactions on Lands in the mäzgäb of Ḥamärä-Noḫ
Authors: Guebreyesus Namouna
Published: July 2020

The mäzgäb of Ḥamärä Noḫ, also known as the collection of documents preserved in the manuscript, London, British Library, Oriental 508 and edited by Guidi in 1906, comprises legal texts registered adjoining religious texts. This manuscript is a Four Gospel manuscript from the church of Ḥamärä Noḫ founded by Tewoflos in 1709. The accounts of the texts date from the 18th century, from the reign of aṣe Tewoflos to the reign of aṣe Gwalu, and take place in Gondär. One buyer who was very active in transactions around Ḥamärä Noḫ was Liqe Bätre. The contracts of sale in which he is named use complicated patterns and suggest a refined legal conception of land ownership, with the employ of the notion of rim. This type of tenure has received diverging interpretations by scholars. The study of Liqe Bätre’s contracts from Oriental 508 allows an understanding of rim as a type of tenure that may not include ownership of land. The justification for the exaggerated precaution of establishing guaranties in sales lies in the precarious tenure that this notion can imply.