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Biocomposites sheets were prepared by compression molding from mixtures of corn starch plasticized by glycerol as matrix and cellulose fibers, extracted from used office paper, as reinforcement filler with contents ranging from 0 to 8% wt/wt of fibers to matrix. Properties of composites were determined by mechanical tensile test, differential scanning calorimetry, thermogravimetric analysis, water absorption measurement, and scanning electron microscopy. The results showed that higher fibers content raised the tensile strength and elastic modulus up to 109% and 112%, respectively, when compared to the non-reinforced thermoplastic starch (TPS). The addition of the fibers improved the thermal resistance and decreased the water absorption up to 63.6%. Scanning electron microscopy illustrated a good adhesion between matrix and fibers.

This study was carried out to investigate the effect of beating process to the characteristics of pulp and paper produced from oil palm oil male flower spikes (OPMFS). OPMFS pulp was prepared according to chemical Soda-AQ pulping process. 60 gsm handsheet of oil palm male flower spikes paper were prepared from OPMFS pulp with four different beating times which are 0 revolution, 1000 revolutions, 2000 revolutions and 3000 revolutions. All physical and mechanical characteristics were investigated according to TAPPI and MS ISO standards. The results show that overall physical and mechanical characteristics of POMFS paper were influenced and enhanced by beating process between 0 until 3000 revolutions. This research demonstrate some potential characteristics of palm oil male flower spikes (OPMFS) paper to be investigated as a newly explored non-wood based raw material for papermaking raw material for papermaking.

This paper presents the results of heat and compression effects on moisture content and water absorption properties in the manufacturing of disposable plate made from Pineapple Leaf Fiber-based material (PALF). The plate was made of PALF and sugarcane bagasse waste as an alternative to polystyrenes, designed to promote the green technology effort on food packaging material. Two different specimens were produced with different compositions of PALF/sugarcane bagasse series N2T8 ( 20 wt% of Pineapple leaf fiber and 80 wt% of sugarcane bagasse ) and series N8T2 ( 80 wt% of Pineapple leaf fiber and 20 wt% of sugarcane bagasse). The specimens were produced using a hot press machine set at compressing temperatures of 50°C, 100°C and 150°C with constant pressure of 0.024 MPa for 10 minutes. Moisture content and water absorption tests were carried out on the specimens to determine the moisture content and water absorption properties. The lower water absorption was obtained for specimen N8T2 because PALF potential to water resistance. This range of properties is expected to be good enough for the requirement of disposable plate and it has the potential as a suitable raw material for strength and lightweight in the manufacturing of disposable plates.

In this paper, storage effect on biodiesel properties for high blending ratio and the emission are evaluated. The blend level of biodiesel is denoted as B, followed by the percentages of pure biodiesel. The samples used are conventional diesel (STD), B80, B90 and B100 were stored at ambient temperature (24 °C) for nine week. The properties of biodiesel, acid value, flash point, viscosity, density and water content were measured according to ASTM D6751 biodiesel fuel standard. Results show there are no significant effects on it properties while stored in long duration at ambient temperature. Meanwhile, increasing biodiesel ratio is found to enhance the combustion process, resulting in decreased the HC for emissions.

As the key process of weaving, sizing is one of the processes which are of great costly and serious pollution in the whole cotton-textile production chain. Great efforts had been made to study new sizing to reduce costs and environment pollution. In this paper, Methyl cellulose ether (MC) and hydroxypropyl methyl cellulose ether (HPMC) were prepared by the hemp core and further used as a textile sizing. The chemical structure of the hemp cellulose ether was characterized by the FTIR analysis. The paste viscosity was tested by the Viscometer. The sizing properties of hemp cellulose ether were evaluated by the weaving process. The results indicated that the wrap breakage rat, weft breakage rate and loom efficiency of MC and HPMC blended sizing was similar to those of PVA sizing. Compared to COD in the desizing wastewater of 3600 mg/L of PVA, the COD of hemp sizing was very small. It was 330 mg/L. Therefore, it is concluded that the hemp core ether is a new and environment-friendly textile sizing, which has low cost and contributes a healthier ecosystem.

Composite materials are created as a quite complex architecture which includes a fibre reinforcement structure and matrix material. Many material parameters play a role when composite structures are modelled, e.g. in finite element models. In addition to the properties of the raw fibre and matrix materials which are used, also geometrical parameters have a significant effect on structural characteristics. Fibre reinforcement geometry together with material properties of fibre and matrix determine homogenised material properties.The first part of the paper gives an overview of the most important processes which are used in composites processing industry. The factors which affect variability are also listed, and the effect of variability on material parameters is mentioned as well. The second part of the paper elaborates the identification of geometrical variability of the fibre reinforcement structure which is encountered with one particular type of composite material, namely a twill 2/2 carbon fibre weave with an epoxy matrix.

In the present paper, the Preisach model of hysteresis is extended to structural analysis of trusses damaged under cyclic loading in plastic range. Parameters for the Preisach model of cyclic plasticity are obtained from uniaxial loading experiment. Damage, as a consequence of micro cracks appearance due to alternating loading in plastic domain, is modeled using brittle elements according to Preisach procedure. Results of this research are compared with the already existing in the literature. In the paper examples of trusses under various cyclic loadings are presented. Applied Mechanics and Materials

The structural performance of thin-walled compression members are subject to the effects of local buckling, interaction between buckling modes, loading end conditions and material yielding and that due to these effects the compressive carrying capability of thin-walled members can be significantly diminished. This paper employs the finite element simulation to examine the local-overall flexural interaction response of pinned-ended thin-walled I-section columns that covers the complete compressed loading history from the onset of elastic local buckling through the nonlinear elastic and elasto-plastic post-buckling interactive phases of behaviour to final collapse and unloading. A detailed account of the growth and redistribution of stresses on the surfaces is given in the paper. Pinned-ended conditions means, of course, simply supported conditions at the column ends with respect to global rotations and the ends of the constituent plates of the cross-section can be treated as either locally rotationally constrained or locally rotationally free. The numerical simulations take into account the influence of material nonlinearity and geometrical imperfections on the compressive ultimate failures of the sections, however, the study is limited to the interaction of local buckling with overall flexural bending as well as locally rotationally constrained condition. This paper shows that the ultimate failure of the columns is related with yielding on the compression sides of the outer surfaces of the section walls at the web, flanges and section junctions mostly located along the length of the columns.

The competency of acoustic emission (AE) technique in order to predict the fatigue life of SAE 1045 carbon steel was discussed in this paper. The correlation of the AE parameter and the number of cycles to failure of the tested specimens were established via the statistical approach. In this paper, The AE hits were selected as the functional parameter. The fatigue life values were calculated using the strain-life approach of three models; Coffin-Manson, Smith-Watson Topper and Morrow. Both AE and strain signals used in the analysis were captured using the AE sensor and strain gauge that were attached to the specimen during the fatigue test. The results show that the AE technique has a good potential in assessing the fatigue life with the designed H-N curve (AE hits-number of cycles to failure curve).

Retracted paper: InGaN with high InN molar fraction is a promising material for next generation optoelectronic devices and electronic devices such as solar cells, laser diodes for communications, and high mobility transistors and so on. However, the growth of InGaN with high InN molar fraction is still a tough challenge for metal organic chemical vapor deposition (MOCVD). This paper provides experimental clues for the key factors, including the influences of the growth temperature, the V/III ratio, the group III supply ratio, and the reactor pressure. In addition, the effectiveness of the pressurized MOCVD growth of the InGaN with high InN molar fraction will be testified.

[EN] Construction sector has consumed an important percentage of natural resources and generated much of the waste discharged into the environment in the last decades. This is the reason why the social consciousness has strongly grown towards sustainable development. Concepts such as recycle, reuse, reduce and energy saving are gaining importance in obtaining products under a clearly defined objective of a sustainable development. The revaluation of agroforestry waste has established itself as a solution to the problems associated with these wastes and, increasingly, is being incorporated into the manufacture of new materials. The Wood Plastic Composites (WPC¿s) are an important group within these new sustainable building materials. WPC¿s are obtained from recycled plastics and natural fibres waste. This kind of materials reduces the consumption of resources and the amount of waste. These materials have emerged to replace natural wood in some exterior applications, where the durability of natural wood is most damaged. Natural wood, in addition to the loss of color that suffers in exterior, has other disadvantages such as anisotropy and hygroscopicity. WPC's do not have these drawbacks. In this way, the WPC¿s try to imitate the appearance of natural wood, with a good durability outdoors. Because of this, there are numerous companies that develop WPC products with different plastics and natural waste, with the aim of obtaining the best appearance and durability. In this paper, the color degradation of various WPC materials when exposed to ultraviolet (UV) radiation is evaluated. An artificial aging chamber with a fluorescent UV lamp and a colorimeter have been used to quantify the color parameters. Thus, conclusions are drawn on which plastics and residues achieve a minor alteration of color, an aspect highly appreciated in outdoor applications.

Visualization of work surface topography through simulations is very challenging task in grinding process due to the complexity of wheel-work interactions with a very high number of cutting points (grits). Kinematic mapping of abrasive grits on a three-dimensional wheel topography enables the evaluation of ground surface topography through simulations. In this paper, a method for generating the ground surface topography based on wheel specifications is presented. Abrasive grits size, abrasives volume percentage and their nature of distribution on the wheel surface are considered in the modeling and visualization of wheel topography. The simulation results of ground surface topographies prove the feasibility of the developed method.

The formation of chips in cutting processes is characterised by large deformations and large configurational changes and therefore challenges established modeling techniques. To overcome these difficulties, the particle finite element method (PFEM) combines the benefits of discrete modeling techniques with methods based on continuum mechanics. In this work an outline of the PFEM, as well as an explanation of the finite element formulation are provided. The impact of the boundary detection on the structural integrity is studied. The numerical examples include a tensile test as well as cutting simulations. The paper is concluded by a comparison of cutting forces with analytical results.

Selective Laser Sintering (SLS) has recently become one of the fastest growing additive manufacturing processes due to its capability of fabricating metal parts with high dimensional accuracy and surface quality. Physical modeling of this process plays an important role in properly controlling the process parameters of the process. In this paper, we present a 3 dimensional, adaptive discrete element method for simulation of the SLS process on personal computers. The presented method models the laser-powder interaction at particle level, achieving high simulation accuracy while adaptively increasing the discrete element size as local temperatures drop inside the powder bed for improved efficiency. Numerical shape functions are developed for calculating individual particle temperatures at any point during the simulation. Results show that this physical model improves the runtime significantly in virtual simulation of SLS process without loss of simulation accuracy.

On the macrolevel metal matrix composites (MMCs) resemble a homogeneous material. However, on the microlevel they have an inhomogeneous microstructure. This paper will show how heterogeneities affect the effective macroscopic properties the material, i.e. the effective properties. This investigation is done using computational homogenization techniques. Finite element (FE) simulations were conducted in ABAQUS in combination with MATLAB, using material parameters for aluminum alloy AA2124 and silicon carbide SiC to develop a representative volume element (RVE) of the MMC AMC217xe.

Particle analysis methodology is presented, together with the morphology of the wear debris formed during rolling contact fatigue. Wear particles are characterised by their surface topography and in terms of wear mechanism. Rail-wheel materials are subjected to severe plastic deformation as the contact loading progresses, which contributes to a mechanism of major damage in head-hardened rail steel. Most of the current methodologies involve sectioning of the rail-wheel discs to trace material damage phenomena such as crack propagation and plastic strain accumulation. This paper proposes methodology to analyse the development of the plastically deformed layer by sectioning wear particles using the focussed ion beam (FIB) milling method. Moreover, it highlights the processes of oxidation and rail surface delamination during unlubricated rolling contact fatigue.

A number of studies have been carried out previously to investigate the suitability of palm oil as dielectric insulation fluid in transformers. Among the important studies is the ageing performance of palm oil. In this paper, a study was carried out to investigate the dielectric properties of Refined Bleached and Deodorized (RBDPO) Olein after subjected to thermal ageing. A low temperature ageing was carried out at 85°C for 5 days. The AC breakdown voltage, dielectric dissipation factor, relative permittivity and resistivity of RBDPO were examined throughout the ageing duration. It was found that the RBDPO performs reasonably well under low temperature ageing.

This paper presents the behavior of 33kV polymer insulator under nominal voltage and impulse by means of lightning activities. The electrical performance of the insulator is translated to electric field under uniform weather conditions which comprises of air humidity and contamination. ANSYS Maxwell modeling software is used to simulate the structure of the polymer insulator based on the real existing insulator’s dimension. The trend of electric field increase is discussed in detail.

The properties of Palm Oil (PO) and Coconut Oil (CO) offer the potential for transformers with non-toxicity, high fire and flash points and better environmental compatibility while compared with those filled with Mineral Oil (MO). This potential has led to intensive studies of electrical performance of biodegradable oil especially in evaluating the electrical performance under lightning impulse voltage in recent years. This paper presents the investigation on the impulse breakdown voltage of PO and CO in such a uniform field. The PO used in this study is Refined, Bleached and Deodorized Palm Oil (RBDPO) Olein type. Two testing methods, rising-voltage and up-and-down are considered for both oils with different gap distances (2.0 mm and 3.8 mm). Testing methods including rising-voltage method and up-and-down method have no notable influence on the breakdown voltages of RBDPOs and CO compared to MO.

This paper presents of Polymer Matrix Composite (PMC) as feedstock used in Fused Deposition Modelling (FDM) machine. This study discussed on the development of a new PMC material by the injection molding machine. The material consist of copper powder filled in an acrylonitrile butadiene styrene (ABS), binder and surfactant material. The effect of metal filled in ABS and binder content was investigated experimentally by the Melt Flow Index (MFI) machine. Based on the result obtained, an increment of copper filled in ABS by volume percentage (vol. %) effected on melt flow index results. With highly filled copper in PMC composites increase the melt flow index results. It was concluded that, the propensity of the melt flow allow an internal force in PMC material through the injection molding and FDM machine.

This paper discusses a finite element analysis of cylinder on flat contact configuration subjected to constant normal load and reciprocating tangential displacement with linear kinematic hardening models based on bi-modal Ti-6Al-4V cyclic stress-strain curves. The predicted evolution of plastic deformation such as the equivalent plastic strain, tangential plastic strain and shear plastic strain distributions on the contact region has been studied along with its respective predicted stress distributions. The effect of applied forward and backward sliding displacement movements on predicted stress and strain distributions have also been looked at. It is found that the stress distributions predicted for kinematic hardening model is similar for forward and backward movements while the predicted plastic strain distribution is increasing with reciprocating sliding movement. The predicted value keep increasing when it moves forward, backward and finally moves forward again. This is due to large strain effect of the model and its dependant on the displacement movement amount.

A hydroxyapatite is known as one of vital materials and common use in biomedical field and concentrated in clinical area. In relation to the above, the development of hydroxyapatite powder becomes an attractive research lines due to simplify in produce it. Thus in this paper the researcher stress out about Hydroxyapatite powder gained from the natural sources or so called as the waste of Tilapia bone and scales. The raw bones of and scale were undergo to crushing process to form in powder size (0.2 mm) then analysed by X-ray Diffraction (XRD) to identified the mineralogy of raw bone. Moreover the powder of fish bone and scales also go through to Scanning Electron Microscope (SEM) machine to analyse the microstructure of the powder while EDS act as device to determine the chemical composition of the sample powder. Sample powder then forward calcination process at selected temperature range to as a cheaper method in obtained hydroxyapatite raw sources. The range of calcination temperatures are between 800°C to 1000 °C. The sample preparation were analysed in both condition before and after calcination process by using XRD, SEM and EDS. The HAP crystalline composition of tilapia bones for raw powder and at 800 °C are similar with HAP pattern (JDS 00-009-0432) and the chemical reaction is Ca5(PO4)3(OH) then at temperature 900 and 1000 similar to HAP pattern (JDS 00-055-0592) with chemical reaction equal to Ca10(PO4)6(OH)2.

This paper presents the combination technique in developing the woven kenaf fiber that is used as a new method to improve energy absorption performance. This method focuses on the effect energy absorption of angle orientation. Due to the low density, natural fiber such as kenaf fiber provides comparatively good mechanical properties. Thus, natural fibers have high potential for better reinforcement in light weight structures on automotive applications. Total force, total energy, and energy absorption of natural fibre reinforced composite for different type’s natural fibre and angle orientation are discussed and reviewed.

Self-compacting concrete which commonly abbrevited as SCC is a special concrete that have the ability to consilodate fully under its own self-weight without any internal or external vibration. This paper presents the experimental investigation carried out to study the strength of self-compacting concrete incorporating bottom ash at different replacement level of natural sand. The composite cement was used and the replacement level of bottom ash to natural sand is set up to 30% by volume. The strength properties such as compressive strength, split tensile strength and flexural strength of the concrete at the age of 7 and 28 days of curing day were conducted. Results shows that the strength of the concrete with bottom ash increased up to replacement level 15% higher than control specimens. This show that bottom ash can be used as supplimentary cementitious materials, having the pozzolanic reactivty.

Keyword : Keyword: Speed of penetrations, CPT, Mackintosh probe, rate effect, shear strength Abstract. A wide range of industrial applications, on land and offshore, require the solution of time domain problems and an associated understanding of rate effects in clay soils. In recent decades many researchers have examined the correlation between shear strength of soils and variation of shear strain rate and it is generally accepted that the strength increases by 1-5% for each order of magnitude increase in shear strain rate. This paper discusses the effects of penetration rate on the penetration resistance (qc) by using cone penetration test (CPT) test setup. The research had been conducted at RECESS and cone penetration test were used in three selected range of rate which were 0.5 cm/s, 1cm/s and 5cm/s. In addition, Mackintosh probe test had been considered as comparison with CPT test for the unconfined compressive strength. The result shows different penetration rate influenced the soil shear strength. For the slowest rate (0.5 cm/s), the shear strength was approximately 0.15% less compared to the standard rate (2 cm/s). However, for the highest rate (5 cm/s), the shear strength was 0.22% more than the reference rate (0.5 cm/s). In conclusion, it is suggested that the RECESS clay soil influenced by the rate effect and in agreement with previous research findings.

The measurement of a small strain stiffness can be conducted via measuring the velocity of the material. The stiffness is an indicator for the strength of the material. It is an important parameter to understand the response of the material when it received the loads. The seismic surface wave has an advantage technique to measure the stiffness of the materials due to factors of time consuming and non destructive method. In addition, the test can be conducted on the surface of the material, thus ease to conduct the test. The continuous surface wave is using a steady state seismic source which can be controlled it frequency. Thus, sufficient energy at specified frequency can be obtained. This can be influenced the quality and reliability of the data. In addition the stiffness at specified depth can be identified. In this paper, in-house development of the equipment and the system was described. A few testing was conducted on different materials in order to assess the reliability of the developed system as well as the stiffness of the materials. As a result, the stiffness assessment on the concrete mortar, asphalt pavement and concrete wall showed the values were in the range of 0.25 to 0.33GPa, 0.05 to 0.13GPa and 0.35 to 0.51GPa respectively.

The fuel-air mixing during burning process provides significant effects to the fuel atomization and flame development thus predominantly influences to the behavior of particulate matter (PM) and NOx production. The variant in fuel injection characteristics are widely used in the field of burner system nowadays. Spray nozzles having various operating conditions dependedon the design of nozzle and it was precision components designed to perform very specific spray characteristics under specific conditions. This review paper focuses on spray characteristics, effects of geometry of injector, influence of fuel and hole shaped nozzle with cylindrical and conical holes on spray characteristics. The parameters are discussed based on an overview of the research in the field of simulations with nozzle shaped injectors. Massive researchers had reported that conical nozzle hole is better than cylindrical nozzle due to it contributed suppression of cavitation in nozzle hole, slowed down primary breakup process and thus produced larger spray droplets, high spray

This paper presents the melt flow index (MFI) of acrylonitrile butadiene styrene (ABS) and recycle ABS filament wire for Fused Deposition Modeling (FDM) machine. In this study, the effect of MFI on recycle ABS material was investigated experimentally based on the melting temperature, density, screw speed and material properties. The MFI result on ABS recycle in wire filament was investigated using Melt Indexer Machine (MIM). Based on the result obtained, it was found that, ABS recycle was increase the density and MFI results. It can be observed that, the higher temperature was melt the recycle ABS material through the MIM and extruder machine.

Titanium is a lightweight metal with an outstanding combination of properties which make it the material of choice for many different applications. This paper investigates the structure, surface characteristics and electrical properties of the Titanium Dioxide (TiO2) thin film, deposited by chemical vapor deposition (CVD). The deposition temperature was 1000°C with 3 different positions of the glass substrates. The surface morphologies were examined using a field emission scanning electron microscope (FESEM) and an atomic force microscopy (AFM). In order to investigate the structural properties, the TiO2thickness was measured using a surface profiler. The optical properties of TiO2were measured using an ultraviolet visible spectroscopy (UV-Vis). The surface morphology was found to be sensitive to the deposition parameters and the growth TiO2is more uniform when the position of substrate is closed to the starting material.

This paper investigates the performance of rice husk ash (RHA) in a fine grained mortar. RHA produced from control combustion of rice husk. Fine grained mortar (FGM) is a mortar containing fine sand with a maximum size of 1mm. Chemical composition of RHA and Ordinary Portland Cement (OPC) were investigated using XRF in order to know the silica content in these materials. The particle size of RHA was analyzed to make sure it fineness is same with OPC after grinding. Compressive and flexural strength of FGM were tested on mortar prism for size 40mm x 40mm x 160mm with replacement of RHA 10%, 20% and 30% by weight of cement at 7 days and 28 days ofcuring. All 24 specimens of FGM were caste and tested. The flexural strength, compressive strength of FGM have shown quite encouraging and interesting results. The optimum replacement of RHA in FGM from compressive and flexural strength is 20% by weight of cement.

value. Abstract. The aim of this paper is to investigate the effects of voltage flow (V) in the alkaline electrolyser system and the pH value (pH) of the electrolyte used in the electrolyser. The output measurement of both investigated factors in in the flow rate of the hydrogen gas produced by the system per minute (ml/min). The voltage flow was altered in the system by altering the voltage supply from the workbench power supply ranging from 11V to 14V. The pH value of the electrolyte solution in the electrolyser was altered by the addition of Potassium Hydroxide (KOH) in the distilled water. The pH value samples of the tested solution ranging from 13.0 to 14.0 pH value due to the limitation of the electrolyser used in this experiment. The results found that, the hydrogen gas produced per minute increases with voltage flow in the system. The flow rate of the hydrogen gas produced however only increases when the solution's pH value reaches at 14 pH level and unreactive below the value.

ZnO nanorods (NRs) arrays were synthesized by chemical solution deposition (CSD) method on commercial glass substrate with ZnO thin film act as seed layer prepared by sol-gel spin coating. The effect of annealing temperature of 150°C, 250°C and 500°C, respectively, on the structural growth was investigated. The observation reveals the structural improvement as the annealing temperature increased. The influence of gadolinium doping to ZnO NRs arrays was explored upon the structural and optical features. The FESEM imaging along with XRD, AFM and UV-Vis analysis were conducted to dissect the information gained by performing a study case on various gadolinium doping content in the range of 1 at. % to 4 at. %. Based on the results, the correlation between the doping content were drawn in details in this paper.

Understanding the interference of multi-bead parameters on surface smoothness is essential for accuracy of the formed parts made by welding rapid forming. This paper presents an investigation on surface smoothness of multi-bead aluminium alloys. Deposition path planning and overlap ratio is manipulated in order to improve surface smoothness. Observation on bead cross section indicates that deposition path planning has remarkable effect on the surface smoothness. Multi-bead that developed using continuous path planning has surface smoothness of 0.46 mm – 1.34 mm and most bead present wavy type surfaces. The surface smoothness is improved by increasing the overlap ratio. Meanwhile, skip path planning produced good surface smoothness of 0.11 mm – 0.28 mm. An improved surface smoothness featuring flat surface type is obtained with this path planning.

This paper reports the results on cracking propagation and pattern of reinforced concrete (RC) beam conducted using irregular-shaped Polyethylene Terephthalate (IPET) as a fibre. Three volume fraction of IPET fibre is used namely, 0.5%, 1% and 1.5%. All RC beam specimens are tested under four point loading under flexural capacity behaviour. Prior to structural test, the materials properties which include the compressive and tensile strength test and modulus of elasticity test were determined. The results than are compared with control RC beam. It is found that the RC beam with IPET fibre does not significantly change the behaviour of failure mode, cracking propagation and pattern compared to control RC beam.

The usability of the clay fraction as one of the criteria in the assessment of liquefaction susceptibility is questionable since year 2001. The use of plasticity index to replace clay fraction as a controlling parameter in the criterion is proposed. This paper aims to compare the usability of different parameter in describing the cyclic behaviour of sand-fines mixtures with various plasticity characteristics. The sand-fines mixtures were reconstituted by mixing clean sand with two types of plastic fines at different percentages by weight, at a standardized ratio of 80% of clean sand with 20% of plastic fines. All soil samples were mixed using the dry tamping method to achieve a constant relative density of 20% throughout the specimen. The soil specimens are tested with stress controlled cyclic triaxial apparatus under consolidated undrained condition, with an effective confining pressure of 100kPa. The soil specimens were considered liquefy when the value of pore pressure is equivalent to the initial cell pressure, resulting zeroes effective stress in soil specimen. The results showed that the liquefaction resistance of the sand-fines mixtures increased as the value of plasticity index increased. The plasticity index is a better indicator to describe the liquefaction susceptibility of sand-fines mixtures compare to clay content, plastic limit and activity.

This paper presents numerical analysis of stress intensity factors (SIFs) of inclined cracks due to mechanical mismatches. According to literature survey, tremendous amounts of SIFs can be found elsewhere. However, the SIFs for inclined cracks are difficult to obtain especially when mechanical mismatch at the crack interface are considered. ANSYS finite element program is used to model the cracks embedded in plain strain plates. The cracks are oriented at the interface between two different materials and subjected to mode I tension loading. It is showed that when mechanical mismatches are introduced the mode I SIFs reduced and on the other hand mode II SIFs increased. When the cracks are inclined, the mode I SIFs diverged but it is not for mode II SIFs and gradually increased when compared with the normal cracks.

This paper describes the analysis on the characteristics of semi-permeable membrane sound absorber. The effects of membrane surface tension on the sound absorption characteristics were investigated. The characteristics of the membrane absorber was measured experimentally in terms of Sound Absorption Coefficient, α and Noise Reduction Coefficient, NRC. The membrane is made of thin, flexible, semi-permeable latex material and the tests were carried out by using impedance tube method according to ISO 10534-2 standard. The results showed that the surface tension has significant influence on the sound absorption characteristics. For the parameters used in the laboratory work, specimen with unstretched surface tension has the best absorption performance.

This paper discusses the experimental results on the mechanical properties of hybrid fibre reinforced composite concrete (HyFRCC) containing different proportions of steel fibre (SF) and polypropylene fibre (PPF). The mechanical properties include compressive strength, tensile strength, and flexural strength. SF is known to enhance the flexural and tensile strengths, and at the same time is able to resist the formation of macro cracking. Meanwhile, PPF contributes to the tensile strain capacity and compressive strength, and also delay the formation of micro cracks. Hooked-end deformed type SF fibre with 60 mm length and fibrillated virgin type PPF fibre with 19 mm length are used in this study. Meanwhile, the concrete strength is maintained for grade C30. The percentage proportion of SF-PPF fibres are varied in the range of 100-0%, 75-25%, 50-50%, 25-75% and 0-100% of which the total fibre volume fraction (Vf) is fixed at 0.5%. The experimental results reveal that the percentage proportion of SF-PPF fibres with 75-25% produced the maximum performance of flexural strength, tensile strength and flexural toughness. Meanwhile, the percentage proportion of SF-PPF fibres with 100-0% contributes to the improvement of the compressive strength compared to that of plain concrete.

This paper presents the result of an experimental investigation of axial behavior of concrete-filled double skin steel tubular (CFDST) columns exposed to high temperature under the action of monotonically applied concentric axial loads. The columns were exposed to ASTM E-119 standard fire curve until 600°C and kept constant for two different exposure time (i.e., 60 and 90 minutes). Failure patterns and reduction in strength, ductility and stiffness of CFDST columns are reported. Factors influencing the strength, ductility and stiffness of CFDST columns during fire exposure, i.e., exposure time, temperature of concrete core and temperature of inner steel tube, are also discussed.

Schlieren optical visualization technique system is the unique technique due to the ability in producing a neutral image easily-interpretable image of refractive-index-gradient areas. The Schlieren system provides a method for viewing the flow through the transparent media and the most using this technique is to photograph the flow. This paper presents the review of the application of the Schlieren optical visualization system external and internal combustion engine in order to observe the fuel-air mixing and flame development during the burning process. The basic technique of Schlieren system, especially for Z-type and two mirror Schlieren system provide a powerful and clearly image to visualize the changes of the density in a transparent medium. This method can capture spray evaporation, spray interference and mixture formation clearly with real images. Analysis of optical image visualization observations reveals that the mixture formation of fuel and air exhibits the influence of the ignition and flame development. Thus, the observation of systematic control of the creation of a mixture of experimental apparatus allows us to achieve significant progress in the combustion process and will present the information to understanding the basic terms of reduced fuel consumption and exhaust emissions.

We have reviewed humidity sensors based on the Zinc oxide (ZnO) humidity sensor. There are only a few papers reviewing on the ZnO humidity sensor. The characteristics, structures, advantages, and fabrication methods of ZnO have been studied to understand the suitability of the ZnO to be applied at different kind of condition such as for extreme environment, low level humidity detection, and very high humidity level circumstances. The electrical and physical properties of ZnO humidity sensors such as sensitivity, response time, stability, uniformity, and crystallinity have also been discussed in this review. ZnO nanostructures have been widely used for humidity sensors because of its’ good stability, high sensitivity for humidity-sensing, low cost, and has a wide band gap. Sol-gel preparation method is commonly used to for ZnO humidity sensor fabrication since it can produce a film with high uniformity, simple process and low cost. Keywords: Humidity Sensor, Metal Oxide, Semiconducting Type, Ceramic Type, Humidity-Sensing, Band Gap, Sol-Gel Preparation Method.

Metal injection moulding has gain much attention due to flexibility and high productivity of the plastics injection moulding with the powder metallurgy method of sintering. In order to gain better shape retention, optimum density of green part is required. This paper deals with the application of Taguchi optimisation technique on getting the optimum density for Metal Injection Moulding (MIM) components base on certain parameters in process injection. For this purposes only 3 process parameters were considered here including its interactions which are injection pressure, injection temperature and mould temperature. Since its more close to the final products these parameters were selected and other parameters will be kept constant. An orthogonal array of L16 experimental base design was conducted. Confirmation test will be done base on Signal-to-Noise (S/N) ratio and it Means.

In order to reduce cost of production and decrease environmental pollution, so many research work has been conducted and still ongoing as to the possibility to use kenaf fiber in high technologies production. Its shows that kenaf fiber have potential reinforced fiber in thermosets and thermoplastics composites. This paper presents the various of challenges to produce kenaf as a reinforcement which mean to identify the limit of kenaf fiber performance after over all of challenging factor. The main factor that touch on interphase, water absorption, chemical treatment and fiber fraction which mean affect the performance of kenaf fiber as a reinforcement are discussed.

This paper describes the investigation and analysis on two materials in which one material is a relatively good sound absorber at low frequency range and another is a relatively good sound absorber at high frequency range, combined together in layers to form a better sound absorber for a wider range of frequencies. The layer combinations of the materials are varied and the values of Sound Absorption Coefficient, α are measured experimentally by using impedance tubes with two microphones transfer function method according to ISO 10534-2 standard. The results obtained are compared in terms of the order of material and the number of layer combinations of materials for each sample. The orders of combinations and number of layers of combinations have significant influence on the sound absorption characteristics. The order of materials has reversed effect on Sound Absorption Coefficient, α as the number of layer combination is increased. Increase in the combination number will make the specimen performed relatively better at a wider frequency range.

Uniform Titanium dioxide (TiO2) thin film is essential for application in high performance solar cells. A low cost approach using TiO2nanopowder extracted from tin mining waste to deposit TiO2thin films is demonstrated in this paper. Furthermore, the influence of different solvents (ethanol, acetone, isopropanol and ethylene glycol) on the formation of uniform TiO2thin films in sol-gel technique is studied. The films were characterized by an atomic force microscope (AFM), ultra violet – visible spectrometer (UV-Vis) and a current-voltage (I-V) measurement system. The correlations of the structural, optical and electrical behavior to the type of solvent used were discussed in details.

This paper presents the formation of highly crystalline ZIF-8 using microwave-assisted solvothermal method. The crystallinity of the ZIF-8 particles was characterized using X-ray diffraction. The lattice vibrations of the structure in the ZIF-8 framework were determined through Fourier transforms infrared spectroscopy. The morphology of the ZIF-8 particles was observed through scanning electron microscopy. The results showed that, 0.5 hour was sufficient for the formation of highly crystalline ZIF-8 particles using microwave-assisted solvothermal method under temperature 120 oC.

In recent years there has been renewed interest in zinc oxide semiconductor, mainly triggered by its prospects in optoelectronic applications. Doping ZnO with various elements has been a popular technique to gain the extrinsic properties for device applications. In this work we have studied the effect of Gadolinium (Gd) concentration on properties of sol–gel derived Gd doped ZnO films. The Gd concentration varying from 1 to 8 atomic percent (at.%). The structural, morphological and optical analyses were monitored by (XRD, Bruker D8 Advance), atomic force microscope (AFM, Tenko XE-100) and ultra violet-visible spectrophotometer (UV-Vis, Shimadzu UV 1800), respectively. Observations from the XRD results showed that all films exhibit the hexagonal wurtzite crystal structure and higher peak intensity observed at (002) peak. Based on XRD analysis, we also found that Gd concentration has a significant effect on the crystallite size and strain of the films. Moreover, the AFM analysis revealed that the surface become more uniform and denser as the Gd concentration increased. In addition, the optical transmittance spectra indicate that all films were highly transparent (>90%) in the visible range which slightly improved with increasing Gd concentration. The detail explanation on the mechanism will be discussed in detail in this paper.

This paper investigates the parameter optimization of a preheating method on stainless steel SUS304 prior to aluminium-stainless steel dissimilar welding. The welding method used was metal inert gas (MIG) with butt joint type weld. The Taguchi L9 orthogonal array was used to investigate the optimum parameter, while the mechanical strength was investigated using tensile test. Optimum levels of the process parameters were analyzed using the Taguchi parametric design approach. Parameter analysis of the tensile test results indicate that the preheated specimen with 90 °C have the maximum ultimate tensile strength of 111.27 MPa. This value is in close proximity to the calculated value of 109.02 MPa with 2% error. Through analysis of variance (ANOVA), the welding current was the dominant contributing factor with 40%. It can be concluded that the highest tensile value (111.27 MPa) for AA6061-SS304 dissimilar welding was obtained using 90 °C preheating, voltage of 17.5 V and current of 110 A of current.

The main objectives of this paper is to find the way for solving the problems of aluminum extrusion process, and improve the mechanical properties of the products through a smart design, modelling and simulation of this process by using finite element method (FEM). For the purpose to model a (2D) two dimensions warm aluminum extrusion process, ABAQUS software was used to set up the finite element simulation. The main parameters which have major effects on this process like extrusion stresses, temperature, and die geometry, i.e. extrusion radius, were taken into consideration. Aluminum alloy (Al-2014) was used as the billet material, with 40 mm diameter and 75 mm length. It is important to preheat the billet from the beginning to a specific temperature, and then pressurizes it into the die. This process is an isothermal process with an extrusion ratio of 3.3. Subsequently, the optimized algorithm for these extrusion parameters was suggested based on the simulation results. The results suggest that the large die angle needs a less extrusion load than the small die angle. In all die geometry used, the deformation of aluminum billet, which caused by shearing and compression stresses, happened in a small sectional area, i.e., bearing area. The results also showed that the values of these stresses can increase or decrease depends on the die entrance angle and the die bearing length. To avoid the effects of these stresses on die dimensions; the hardness, material selection, and geometry should be well calculated.

This paper presents the results of using ground dune sand (GDS) and ground granulated blast furnace slag (slag) as high volume cement replacement materials. In this study, plain and four blended mixtures were fabricated and cured under normal and autoclave conditions. For the blended mixtures, 40% GDS by weight of the total binder materials and different percentages of slag (15%, 30% and 45%) were incorporated as partial cement replacement materials. The effect of curing conditions (normal and autoclave) on the compressive strength of prepared mixtures was studied. The results showed that, for the autoclave cured mixture, up to 85% of cement can be replaced by GDS and slag without significant drop in the compressive strength. Microstructure analyses using scanning electron microscope (SEM) and X-ray diffraction analysis (XRD) were carried out to examine the microscale changes of the hydrated mixtures. The SEM revealed the formation of thin plate-like calcium silicate hydrate and compacted microstructure of autoclave cured mixture. XRD showed the elimination of calcium hydroxide and existence of residual crystalline silica of all blended mixtures.