FATIGUE FEATURES EXTRACTION OF ROAD LOAD TIMEDATA USING THE S-TRANSFORM

S. ABDULLAH,C. K. E. NIZWAN,M. F. M. YUNOH,M. Z. NUAWI,Z. M. NOPIAH 한국자동차공학회 2013 International journal of automotive technology Vol.14 No.5

This paper presents the algorithm development of a new fatigue data editing technique using S-T approach. Ingeneral, the S-transform (S-T) is a time-frequency spectral localization method which performs a multi-resolution analysis onsignal. This method represents a better time-frequency resolution especially for non-stationary signal analysis. This techniquewas developed to produce shortened fatigue data for fatigue durability testing. The S-T method was applied to detect thedamaging events contained in the fatigue signals due to high S-T spectrum location. The damaging events were extracted froman original fatigue signal to produce the shortened edited signal which has equivalent fatigue damage. Three types of road loadfatigue data were used for simulation purpose, pave track, highway and country road. In this study, an algorithm wasdeveloped, to detect the damaging events in the original fatigue signal. The algorithm can be used to extract the fatiguedamaging events and these events were combined in order to produce a new edited signal which neglect the low amplitudecycles. The edited signal consists of the majority of the original fatigue damage in the shortened signal with 15-25% timereduction. Thus, it has been suggested that this shortened signal can then be used in the laboratory fatigue testing for thepurpose of accelerated fatigue testing.

Prion Protein Genotypes in Pakistani Goats

Babar, M.E.,Nawaz, M.,Nasim, A.,Abdullah, M.,Imran, M.,Jabeen, R.,Chatha, S.A.,Haq, A.U.,Nawaz, A.,Mustafa, H.,Nadeem, A. Asian Australasian Association of Animal Productio 2008 Animal Bioscience Vol.21 No.7

The PCR-amplified prion protein (PrP) gene was sequenced to determine the frequency of scrapie-associated as well as novel PrP genotypes in 72 healthy goats representing five breeds. A total of six genotypes were detected, resulting from the three reported 143 (H/R), 154 (R/H) and 240 (S/P) and the two novel 39 (S/R) and 185 (I/F) amino acid polymorphisms. Of the four silent mutations 42 (a$\rightarrow$g), 138 (c$\rightarrow$t), 231 (c$\rightarrow$a) and 237 (g$\rightarrow$c) detected in this study, 237 (g$\rightarrow$c) is novel. A genotype (SIP/RFP) harboring three amino acid polymorphisms 39 (S/R), 185 (I/F) and 240 (S/P) was found in few goats. Although both scrapie-associated genotypes with 143 (H/R) and 154 (R/H) polymorphisms and others with 39 (S/R), 185 (I/F) and 240 (S/P) polymorphisms were present in the studied Pakistani goats, their frequency was lower than that of the wild-type genotype SHRIS/SHRIS (34.7%). These results emphasize the need for further sequencing of the PrP gene in a large number of goats representing the five studied breeds, so that overall PrP variability can be assessed in these breeds in research addressing future concerns about scrapie.

Phylogenetic Relationships of the Mutualistic Fungi Associated with Macrotermes subhyalinus in Oman

Hilal S. AlShamakhi,Abdullah M. Al-Sadi,Lyn G. Cook 한국균학회 2023 Mycobiology Vol.51 No.5

The symbiotic association between fungus-gardening termites Macrotermes and its fungalsymbiont has a moderate degree of specificity—although the symbiotic fungi (Termitomyces)form a monophyletic clade, there is not a one-to-one association between termite speciesand their fungus-garden associates. Here, we aim to determine the origin and phylogeneticrelationships of Termitomyces in Oman. We used sequences of the internal transcribed spacerregion (ITS) and the nuclear large subunit ribosomal RNA (LSU rRNA, 25S) gene and analyzedthese with sequences of Termitomyces from other geographic areas. We find no evidence formore than a single colonization of Oman by Termitomyces. Unexpectedly, we findTermitomyces in Oman is most closely related to the symbiont of M. subhyalinus in WestAfrica rather than to those of geographically closer populations in East Africa.

Potential of Activated Carbon Derived from Local Common Reed in the Refining of Raw Cane Sugar

Ibrahim D-Abdullah,Badie S. Girgis,Yassin M. Tmerek,Elsaid H. Badawy 한국탄소학회 2010 Carbon Letters Vol.11 No.3

Common reed (Fragmites australis), a local invasive grass, was investigated as a possible feedstock for the production of activated carbon. Dried crushed stems were subjected to impregnation with phosphoric acid (30, 40 and 50%) followed by pyrolysis at 400~500℃ with final washing and drying. Obtained carbons were characterized by determining: carbon yield, ash content, slurry pH, textural properties and capacity to remove color bodies from factory-grade sugar liquor. Produced carbons possessed surface area up to 700 m2/g, total pore volumes up to 0.37 cm3/g, and proved to be microporous in nature. Decolorization of hot sugar liquor at 80℃ showed degrees of color removal of 60 up to 77% from initial color of 1100~1300 ICU, at a carbon dose of 1.0 g/100 ml liquor. No correlation seems to hold between synthesis conditions and % R but depends on the degree of microporosity. A commercial activated carbon N showed a comparative better color removal capacity of 91%. Common reed proved to be a viable carbon precursor for production of good adsorbing carbon suitable for decolorization in the sugar industry, as well as in other environmental remediation processes.

Growth Performance, Carcass and Meat Characteristics of Black Goat Kids Fed Sesame Hulls and Prosopis juliflora Pods

Abdullah, Abdullah Y.,Obeidat, Belal S.,Muwalla, Marwan M.,Matarneh, Sulaiman K.,Ishmais, Majdi A. Abu Asian Australasian Association of Animal Productio 2011 Animal Bioscience Vol.24 No.9

Finding alternative feeds, such as sesame hulls and Prosopis juliflora species can attenuate difficulties of feed shortage and reduce the cost of animal feed in arid and semi-arid countries. Thirty-two Black male kids with similar initial weights (BW = $16.7{\pm}0.80\;kg$) and $120{\pm}5\;d$ of age, were used to evaluate the effect of replacing barley grains and soybean meal with Prosopis juliflora pods (PJP) and sesame hulls (SH) on growth performance, digestibility and carcass and meat characteristics. Kids were equally divided into four dietary treatment groups for an 84-d fattening period. Treatment diets had similar crude protein (CP) and metabolizable energy (ME). The treatment groups were: (T1) no PJP nor SH, (T2) 10% PJP and 20% SH, (T3) 15% PJP and 15% SH, and (T4) 20% PJP and 10% SH. A tendency was detected (p<0.08) for dry matter (DM), crude protein (CP), organic matter (OM) and neutral detergent fiber (NDF) intakes that were greater for T2 than T3 and T4 while T1 was not different from all other treatment groups. Ether extract (EE) intake was the greatest (p<0.05) for T2 and the lowest for T1. Acid detergent fiber (ADF) intake was greater (p<0.05) for T2 than T1 while T3 and T4 were intermediate. Final live weight, average daily gain (ADG) and feed conversion ratio (FCR) were comparable among different treatment groups. Digestibility of DM, OM, CP, NDF and ADF were similar among all treatment groups, however, EE digestibility was the lowest (p<0.05) for T1 when compared to other treatments. In addition, nitrogen intake, nitrogen in urine and retained and retention percentages were similar among all treatment groups. However, N loss in feces was higher (p<0.05) for T2 than T3 and T4 while T1 was intermediate. No differences were observed among treatment groups with respect to fasting live weight, hot and cold carcass weights, dressing-out percentages, mesenteric fat, visceral organs, carcass cuts percentages and carcass linear dimensions. No differences were also observed for dissected loin, leg, rack and shoulder tissues except in the total bone % for loin cuts and in the meat to bone ratio for rack cuts. T3 has the greatest total bone % and the lowest meat to bone ratio when compared to all other treatment groups. No differences were observed between treatment groups in all quality characteristics of the longissimus muscle. The present study demonstrates the potential of using PJP and SH for growing kids without adverse effects on growth performance, carcass characteristics and meat quality.

New issue of GaN nanoparticles solar cell

M.A. Qaeed,K. Ibrahim,K.M.A. Saron,M.S. Mukhlif,A. Ismail,Nezar G. Elfadill,Khaled M. Chahrour,Q.N. Abdullah,K.S.A. Aldroobi 한국물리학회 2015 Current Applied Physics Vol.15 No.4

This study involves the synthesis of gallium nitride (GaN) nanoparticles (NPs) under different low temperatures using a simple chemical method. The nanoparticles are spin coated on Si substrate to fabricate the solar cell. The FESEM images obtained indicate the presence of cubic GaN nanoparticle with average diameter of 50 nm synthesized at 90 ℃. The spin coating technique deposited n-GaN NPs/Si(111) produced a heterojunction solar cell with fill factor of 0.56 and conversion efficiency of 2.06%. Based on these results, this study proposes a novel low cost technique for the fabrication of GaN NPs solar cells.

EMISSION ANALYSIS OF A COMPRESSED NATURAL GAS DIRECTINJECTION ENGINE WITH A HOMOGENOUS MIXTURE

S. ABDULLAH,W. H. KURNIAWAN,M. KHAMAS,Y. ALI 한국자동차공학회 2011 International journal of automotive technology Vol.12 No.1

In an era in which environmental pollution and depletion of world oil reserves are of major concern, emissions produced by automotive vehicles need to be controlled and reduced. An ideal solution is to switch to a cleaner fuel such as natural gas, which generates cleaner emissions. In addition, control over the in-cylinder air-fuel mixture can be best achieved through a direct-injection mechanism, which can further improve combustion efficiency. This need for cleaner automobiles provides the motivation for this paper’s examination of the use of computational fluid dynamic (CFD) simulations to analyze the concentrations of the exhaust gases produced by a compressed natural gas engine with a direct-fuel-injection system. In this work, a compressed natural gas direct-injection engine has been designed and developed through a numerical simulation using computational fluid dynamics (CFD) to provide an insight into complex in-cylinder behavior. The emissions analyzed in this study were carbon monoxide (CO), nitric oxide (NO) and carbon dioxide (CO2), i.e. the main pollutants produced by natural gas combustion. Based on a stoichiometric mixture, the concentrations of CO and NO were computed using the dissociation of carbon dioxide and the extended Zeldovich mechanism. CO2 was calculated using a mass balance of the species involved in the combustion process. The simulation results were then compared with the experimental data generated by a single-cylinder research engine test rig. A good agreement was obtained with the experimental data for the engine speeds considered for all emissions concentrations.

Evaluating an adhesive effect on core surface configuration for sandwich panel with peel simulation approach

M. K. Faidzi,S. ABDULLAH,M. F. Abdullah,S.S.K. Singh,A. H. Azman 대한기계학회 2021 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.35 No.6

This paper investigates the adhesive effect between the surface layer of sandwich panel with three different core surface configurations by using a peel simulation approach. The sandwich panels with cavity on the core structure can potentially be highly vulnerable to debonding phenomenon when subjected to extreme loading. The three-dimensional sandwich panels based on ASTM D1876 were developed with a finite element modelling and subjected to a constant loading magnitude of 100 MPa in two force directions of 90° and 180°. The result shows that the sandwich panel with a honeycomb core and a dimpled surface core showed increments in stress distributions at bonding area (85 % and 12.8 % at the force direction of 90°; 69.9 % and 11.6 % at the force direction of 180°) compared to that with a solid plate core. Nevertheless, the high shear stress was revealed at a large adhesive area, indicating the high potential for debonding to occur at the adhesive area between panel surface layers. This stress was directly proportional to the total deformation. The size of the adhesive area influences the bonding strength, but an extra reduction in the core density could lead to the early failure of the sandwich panel.

Fatigue crack effect on magnetic flux leakage for A283 grade C steel

M.I.M. Ahmad,A. Arifin,S. ABDULLAH,W.Z.W. Jusoh,S.S.K. Singh 국제구조공학회 2015 Steel and Composite Structures, An International J Vol.19 No.6

This paper presents the characterization of fatigue crack in the A283 Grade C steel using the MMM method by identifying the effects of magnetic flux leakage towards the crack growth rate, da/dN, and crack length.The previous and current research on the relation between MMM parameters and fatigue crack effect is still unclear and requires specific analysis to validate that. This method is considered to be a passive magnetic method among other Non-Destructive Testing (NDT) methods. The tension-tension fatigue test was conducted with a testing frequency of 10 Hz with 4 kN loaded, meanwhile the MMM response signals were captured using a MMM instrument. A correlation between the crack growth rate and magnetic flux leakage produces a sigmoid shape curve with a constant values which present the gradient, m value is in the ranges of 1.4357 to 4.0506, and the y-intercept, log C in the ranges of 4×10<SUP>-7</SUP> to 0.0303. Moreover, a linear relation was obtained between the crack length and magnetic flux leakage which present the R-Squared values is at 0.830 to 0.978. Therefore, MMM method has their own capability to investigate and characterize the fatigue crack effects as a main source of fracture mechanism for ferrous-based materials.

Efficient electrochemical detection of L-lactic acid using platinum nanoparticle decorated Chitosan/ZnTiO3 nanocomposites

M. Faisal,M.M. Alam,Jahir Ahmed,Abdullah M. Asiri,S.A. Alsareii,Raja Saad Alruwais,Norah Faihan Alqahtani,Mohammed M. Rahman,Farid A. Harraz 한국공업화학회 2023 Journal of Industrial and Engineering Chemistry Vol.118 No.-

Herein, a facile L-lactic acid electrochemical sensor based on Pt-nanoparticles (NPs)@Chitosan/ZnTiO3nanocomposites (NCs) coated on a glassy carbon electrode (GCE) is demonstrated. Ultra-sonicationmethod followed by irradiation using an Osram Hg-lamp was applied to prepare Pt-NPs@Chitosan/ZnTiO3 NCs, and the characterization of prepared NCs was executed by Field Emission ScanningElectron Microscopy FESEM, Energy Dispersive Spectroscopy EDS, Transmission Electron MicroscopyTEM, High Resolution Transmission Electron Microscopy HRTEM, Fourier Transform InfraredSpectroscopy FTIR, Ultraviolet–visible spectroscopy UV–vis., and X ray Diffraction XRD analysis. A linearcurrent versus potential responses relation was obtained in a concentration range of L-lactic acid of 0. 30 2.40 mM at differential pulse voltammetric (DPV) analysis in a pH 7.0 buffer medium and resultedconcentration range was defined as the dynamic detection range (LDR) for L-lactic acid analysis. The Llacticacid sensor sensitivity (0.4529 lAlM-1cm2), limit of detection (LOD; 22.36 ± 1.12 lM), and limitof quantification (LOQ; 79.88 lM) were obtained. Besides this, the sensor reproducibility and responsetime were found to be reliable. Finally, the assembled sensor probe was validated by the testing of realsamples, which exhibited acceptable and satisfied results. It is introduced a new route for the detection ofchemicals using novel nanocomposite materials by electrochemical approach for the safety of healthcarefields in a broad scales.