bluuebunny/crossref_metadata_2025 huggingface dataset:
Leachability of Self-Compacting Concrete (SCC) Incorporated with Fly Ash and Bottom Ash by Using Synthetic Precipitation Leaching Procedure (SPLP)
Authors: Abdul Kadir Aeslina , Hassan Mohd Ikhmal Haqeem
Published: July 2015

Fly ash (FA) and bottom ash (BA) are some of waste generated by coal-fired power plants, which contains large quantities of toxic and heavy metals. The combustion of coal after been heated at specific temperatures and pressures in power stations produces ash. FA and BA must be properly managed and disposed without causing any harmful environmental effects. In recent years, many researchers have been interested to study on the properties of self-compacting concrete (SCC) incorporated with FA and BA but there was very limited research from the combination of FA and BA towards the environmental needs. Therefore, this study was focused in determining the leachability of heavy metals of SCC incorporated with FA and BA by using Synthetic Precipitation Leaching Procedure (SPLP). The samples were obtained from coal-fired power plant located at Peninsula, Malaysia. As such, the potential heavy metals leached out from SCC that is produced with FA as replacement for Ordinary Portland Cement (OPC) and BA as replacement for sand with the ratios from 10% to 30% respectively were designated and casted. There are eight heavy metals of concern such as As, Cr, Pb, Zn, Cu, Ni, Mn and Fe. The results show that all heavy metals were leached below the permissible limits from USEPA and EPAV except for As which is the only heavy metal that leaches in large amount even in the control specimen. This is probably due to the influence from the acidic extraction fluid, causing As to leach out in higher amounts during the extraction process. All in all, the uses FA and BA in SCC up to 20% seem to be an environmental friendly practice as far as leaching of heavy metals in the concrete is comply with the standard.
Identification and Expression of Ligninase Enzymes from Tropical Asia Wood Insect for Agro-Pulp Biodelignification: A Theoretical Framework
Authors: Ishak Nadiah , Mohd Kassim Angzzas Sari , Mohd Aripin Ashuvila , Abang Zaidel Dayang Norulfairuz , Zainulabidin Muhd Hafeez
Published: July 2015

Current pulp-processing in pulp and paper based industries are inefficient in removing the lignin as this compound is recalcitrant towards degradation. Transitioning from conventional pulping process into bio-delignification through utilisation of ligninase enzymes is one of the alternatives to improve the ability to fully utilize all components of wood to produce high quality fibres. Extensive research efforts have been focused on increase the production of ligninase enzymes from white rot fungi as a whole organism for industrial applications. However, enzymes activity produced from fungi are rather low as lignin modification is a secondary metabolism in which the enzyme only be expressed under particular conditions. Using genetic manipulations to incorporate genes associate for delignification isolated from different organisms such as tropical Asian wood-feeding insect into bacteria expression system will allow rapid enzyme production. This theoretical framework aims to produce an enzyme with high ligninase activity that will be used for removal of lignin during pulp-processing. These enzymes are thought to be more economically efficient in degrading lignin and involves less use of chemicals thus make this processing more environmentally friendly.Keywords: Biodelignification, Asian wood tropical insect, fungi, ligninase enzyme, bacterial expression system
Coating Bio-Resistance Test of Different Wall Finishing for Isolated Indoor Fungal Treatment by Using Potassium Sorbate Biocide on Wood
Authors: Parjo U.K. , Sunar Norshuhaila Mohamed , Leman Abdul Mutalib , Gani Paran , Emparan Q. , Er Chin Ming
Published: July 2015

Malaysia is located on the equator has resulted in having two seasons wet and dry. Both of the seasons can influence indoor air quality of buildings promoting the growth of fungal. Fungal growth can occur with the combinations of temperature, relative humidity, substrate and others. Indoor and outdoor air quality is essential for building occupants to prevent the infection diseases caused by fungal. The goal of this study is to remediate the growth indoor fungal after treated with biocides on different types of wall finishing and evaluate the efficiencies of biocides to treat indoor fungal. In this study, the biocides are utilized as a coating for coating bio-resistance. The measurements of the fungal growth are made by growing the samples on realistic wood substrates on the different wall finishing such as paints and wallpapers. The mold that grew are affecting most of the rooms is selected. The air sampler that have been used to isolate the samples of indoor fungal according to NIOSH Manual Analytical Method (NMAM 0800), a guideline provided by National Institute of Occupational Safety and Health (NIOSH). The fungal growth was evaluated using the ASTM D5590-00 standard measuring on the surface of substrate. The results show that potassium sorbate as biocide was able to reduce the indoor fungal growth depending on the type of material used in the building.
Response of Single and Grouped Pile Subjected to Lateral Load in Cohesionless Soil
Authors: Khari Mahdy , Kassim Khairul Anuar , Alimohammadi Payman
Published: July 2015

Piles are generally required to transfer load from a superstructure through weak or compressible strata, or through water, on to stiffer and less compressible soils and rock. The pile behavior is very important in Soil-Pile interaction (as known Kinematic Interaction) so that grouped and single pile behavior differs owing to the impacts of the pile-to-pile interaction. In this research presents a series of experimental investigations carried out on single and group pile subjected to monotonic lateral loadings. The aluminum model piles were tested in the different relative densities in Johor Bahru sand. The sand samples were prepared by using the newly designed Mobile Pluviator adopted the air pluviation method. The different configurations of model pile groups for embedded length-to-diameter ratio equal to 32 into loose and dense sand spacing from 3 to 6 pile diameter (D) were conducted. The ultimate lateral load is increased 53% in increasing of s/d from 3 to 6 owing to effects of sand relative density. A ratio of s/D more than 6d is large enough to eliminate the pile-to-pile interaction and the group effects. It may be more in the loose sand.
Effect of Geotextile Encapsulation on Lime Column Axial Stress in Pontain Marine Clay
Authors: Chong Siaw Yah , Kassim Khairul Anuar , Ping Chiet Kenny Tiong
Published: July 2015

Previous researchers reported that problematic soft clay can be improved by deep lime stabilization. However, due to low confining pressure of surrounding soil, problems often occurred at top part of column which reduced the performance of lime column, such as: crushing at column head and higher settlement for surrounding soil at the upper part of column. Geotextile encapsulated lime column (GELC) was proposed in this study. The stresses on column are essential in the analysis on columnar improved soil. Multi-stage loading test was conducted on lime column and GELC stabilized Pontian marine clay aged 14 days, 28 days and 56 days in order to investigate axial stress on lime column and GELC stabilized Pontian marine clay. Geotextile encapsulation increased the compressive strength of lime column about 70 percent at axial strain of 8 percent.
Strength and Stiffness of Artificial Organic Soil Admixed with Lime Zeolite
Authors: Ling Felix N.L. , Kassim Khairul Anuar , Abdul Karim Ahmad Tarmizi , Kan Jing Hui
Published: July 2015

Chemical stabilizers especially calcium based stabilizer, namely lime and cement had been widely used to modify and stabilize the soil. Extensive studies were carried out by researchers to improve the effectiveness and cost-benefit of stabilizers by introducing various types of blended lime and cement. Unconfined compressive test (UCT), one of the most simple and quick strength tests, is commonly used by researchers to indicate the suitability and successfulness of newly introduced stabilizer. The aim of this study is to establish the relationship and correlation of unconfined compressive strength and tangent modulus, E at 50% of unconfined compressive strength of artificial organic soil admixed with lime zeolite. Two types of artificial organic soils, which named as Type A and Type B were prepared manually by mixing commercial kaolin with humic acid powder in different percentages. The artificial organic soils were admixed with blended lime zeolite in different ratio and cured for 7, 28 and 56 days in an oven with controlled temperature of 50°c. The strength of the materials were determined by compressing the specimens using a UCT testing frame and the tangent modulus, E50 were calculated by plotting a linear slope at 50% of ultimate strength over stress-strain curve. The findings of the study showed that the strength and E50 are strongly correlated and important as the indicator of rigidity of the material as well as its capability to resist compressive load.
Effect of Sand Relative Density inside the Geotextile Pillow on the Bearing Capacity of Pad Foundation
Authors: Wimala Mia , Wibowo Herianto
Published: July 2015

A foundation is used to support a building or structure and transmits loads directly to the underlying soil or rock. It must provide an adequate factor of safety against failure of the supporting strata, as well as failure of any excessive settlement which can interfere the function of the structure. Ultimate bearing capacity of a specific foundation is one parameter commonly used to describe the performance criteria of both the soil and the structure above. It can be improved by the inclusion of reinforcements in the ground such as geotextiles. In practice, geotextiles are normally placed directly on the soil in the form of sheet and then covered with aggregates. This research was conducted specifically to investigate the effect of different sand relative densities inside the geotextile pillow, an alternative of geotextile installations in practices, on the bearing capacity of pad foundation by laboratory experiments. A-10 cm x 10 cm pad foundation model was developed in a 1 m3 box filled with sand to actualize this experiment. Geotextile sheet was formed into a pillow, filled with sand with different relative densities and placed at a predetermined depth from the sand surface. As a result, the bearing capacity of the pad foundation model was proved to increase by 50% using a sheet of geotextile compared to the one without any geotextile. Moreover, to the same condition, the use of a geotextile pillow with different sand relative densities inside the pillow, i.e. 30%, 50% and 70% remarkably improved the bearing capacity of the pad foundation model from 150% to 525%. Among the experiment results using a geotextile pillow, the 66.67% addition of sand relative density increased the bearing capacity of a pad foundation model by 100% and 150% with 133.33% of sand relative density. It showed that the increase of the sand relative density inside the geotextile pillow was directly proportional to the increase of the bearing capacity of the pad foundation model.
Effect of Calcium and Sodium Ions in Soft Clay Using Electrokinetic Stabilisation Technique
Authors: Nordin Nurul Syakeera , Tajudin Saiful Azhar Ahmad , Abdul Kadir Aeslina , Yunus Riduan , Mohammad Azmi Mohamad Azim , Mohamed Hanif Mohamed Nur Shafiq
Published: July 2015

Electrokinetic Stabilisation (EKS) technique is a combination process of electroosmosis and chemical grouting. This study involves the investigation on the EKS technique performances in stabilising soft clay soils. Stabilising agents will assist the EKS technique by inducing it to the soil under direct current and its movements which is governed by the principle of electrokinetic (EK). The objective of this research is to study the effectiveness of EKS technique in increasing the strength of soft clays. Two reactors were set up by using 1.0 M of calcium chloride (CaCl2), sodium silicate (Na2SiO3) as the electrolyte and stainless steel plates as the electrodes. EKS technique was being performed for 21 days period of time with a constant voltage gradient (50 V/m). This technique was carried out in two phases where the difference between them is a combination of the stabilising agent. The two combinations of stabilising agents in phase 1 and phase 2 were CaCl2 – distilled water (DW) and CaCl2 – Na2SiO3, respectively. The difference was, one was using distilled water while the other was using Na2SiO3. Results of the strength, liquid limit (LL), plastic limit (PL), plasticity index (PI), pH and ion concentration test towards untreated and treated soil were presented. Showing the strength of treated soil for both phases was increasing near the cathode section with 27.83 kPa and 27.67 kPa. LL and PI for treated soil showed the highest value which occurred near the cathode, while PL seems consistant with the values from untreated soil. The Calcium (Ca+) and sodium (Na+) concentrations in soil were increasing compared to the untreated soil, hence it has proven that the application of stabilisers in EK treatment is more effective in increasing the strength and the stability of soils.
Detection of Twisted Blade in Multi Stage Rotor System
Authors: Ngui Wai Keng , Salman Leong M. , Hee L.M. , Abdelrhman Ahmed M.
Published: July 2015

This paper studies the detection of twisted blade in a multi stages rotor system. Experimental study was undertaken to simulate twisted blade conditions in a three stages rotor system. The feasibility of vibration analysis as the technique to detect twisted blade based on the rotor operating frequency and its blade passing frequency was investigated in this study. Experimental results show that twisted blade can be easily detected by looking into the pattern of the vibration spectrum and its individual peaks.
Comparative Study of Stress-Strain Characteristic of Peat Soil
Authors: Zainorabidin Adnan , Mansor Siti Hajar
Published: July 2015

This paper shows the stress-strain behavior of peat from the perspective of geotechnical engineering based on laboratory test. Stress happens when a load applied to a certain specimen and deformed the specimen while strain is the response from applied stress on a specimen. Peat is known as an ultimate soft soil in engineering terms because it has low shear strength and compressibility. This research is concerned about the stress-strain behavior of hemic peat. The undisturbed samples were collected at Parit Sulong and Parit Nipah, Batu Pahat, Johore, Malaysia. Normal stresses are 12.5kPa, 25kPa, 50kPa and 100kPa. The shear rate to determine the stress-strain on peat is 0.1mm/min. It is a drained condition test. Both results from each method that obtained were compared based on the relationships of stress-strain. Parit Sulong has higher stress-strain than Parit Nipah. If shear stress increased, shear strain also increased. The result shows that, direct simple shear test of stress-strain that tested on hemic is more relevant than a direct shear box because DSS shear the entire specimen of peat while DSB only shear at the center of the specimen. Geotechnical engineers can use the direct simple shear method to understand efficiently about the stress-strain behaviour of peat.
Theoretical and Actual Bearing Capacity of Driven Piles Using Model Piles in Sand
Authors: Leong Wong Kok , Yusoff Nor Azizi , Abd Aziz Ameer Nazrin , Abu Talib Zaihasra
Published: July 2015

In general, increasing of penetration rate may result in an increased of pile capacity. Occasionally, there were differences between theoretical and actual bearing capacity of the piles. Rate of penetration of pile influenced the pile bearing capacity. The bearing capacity of model pile increased as the rate of loading increased based on pile driving formula. Therefore, the study was conducted to determine the bearing capacity of model piles with different penetration forces based on theoretical method and experimented analysis. Five circular hollow section model piles using pipe pile were used to penetrate into cohesionless soil with different penetration force respectively. The loading for ultimate bearing capacity using theoretical calculation was approximately about 0.163kN.However, referring to the limitation of a laboratory setup, the maximum loading was 0.12kN. Several trials had been initiated but when it reached 0.14kN, the setup was unstable and dangerous to be continued. Therefore, the ultimate bearing capacity derived by the pile load test results were based on a pile moved up to 10% of its tip diameter criteria. In the future, both theoretical and actual calculation must be made to avoid any confusion and detect mistakes in near future.
An Overview of Electrokinetic Remediation Assisted Phytoremediation to Remediate Barren Acidic Soil
Authors: Jamil Norashira , Madun Aziman , Ahmad Tajudin Saiful Azhar , Embong Zaidi
Published: July 2015

Electrokinetic has proven to be alternative technique to remediate pollution and increase soil strength for soft soil. This remediation method has been applied to remediate the hydrocarbon and heavy metal contaminant. Phytoremediation is a technique used to remediate the hydrocarbon and heavy metal contaminant. Both of this remediation technique has been proven as attractive alternative to clean up polluted soils. Although barren acidic soil is not categories as hazardous, the necessity of covered soil surface is on demand in order to minimize the surface erosion. Other than that, this remediation technology also helps in horticulture in order to enlarge the plantation and farming area. This paper will explain the formation of barren acidic soil, principles electrokinetic remediation for remediation of barren acidic soil and application of phytoremediation in order to sustain the process of remediation. Correlation of both remediation methods will minimize the acidic ion migration and sustain the pH value on soil surface for grass, vegetable or palm oil plantation.
Challenges for Kenaf Fiber as a Reinforcement: A Review
Authors: Hassan M.A. , Ismail Al Emran
Published: July 2015

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.
An Investigation of Soil Volume Changes at Four Dimensional Points of Peat Soil Sample in Parit Nipah and Pontian
Authors: bin Zainorabidin Adnan , binti Saedon Nursyahidah , bin Bakar Ismail , bt Mohd Seth Nurul Farhana
Published: July 2015

Peat soils occur in many countries and formed naturally through the decomposition of plant and animal matter. These soils are known as a very problematic soft soil due to its low bearing capacity and high compressibility. These two main factors may be based on the characteristics of the soil itself. This study is focused on its physical properties and shrinkage measurement. It is also to investigate the shrinkage measurement that obtained from the diameter at four dimensional points and bar linear shrinkage method for both location peat sample. There are varies method that can be used in order to obtain a full description of the shrinkage behavior of peat. The sample was taken from two different locations which are Parit Nipah and Pontian. Linear shrinkage method is used to determine the soil shrinkage from linear measurements on a bar mould with disturbed soil that passing 0.425mm sieve. However, this method was modified by using undisturbed sample to compare the result with bar linear shrinkage method and the measurement was obtained by the reduction of its diameter at four points of the sample. Linear shrinkage values obtained from Parit Nipah and Pontian by following British Standard method are 34.77% and 33.09% respectively while modified linear method gives the value of 35.25% for Parit Nipah and 32.85% for Pontian. Modified method shows that peat soil from both locations shrinks in irregular shape due to Point C of Parit Nipah and Pontian peat sample has the smallest diameter compared to other points within 24 hours oven-dried. It also shows that Parit Nipah peat soil has a higher percentage of linear shrinkage for both method instead of Pontian peat soil. The linear shrinkage values that obtained from bar linear shrinkage and modified linear shrinkage gives smaller different values which is nearly same for both method.
Numerical Modelling of Prefabricated Vertical Drain for Soft Clay Using ABAQUS
Authors: Ahmad Tajudin Saiful Azhar , Yusof Mohd Fairus , Bakar I. , Marto Aminaton , Zakaria Muhammad Nizam , Abdullah Mohd Ezree
Published: July 2015

Construction, buildings and infrastructure founded on soft clays are often affected by settlement problem. Therefore, Prefabricated Vertical Drain (PVD) is one of the best solutions to accelerate soil consolidation by shortening the drainage path. In this study, numerical investigation was carried out to pursue a better understanding of the consolidation behavior of soft clay improved with PVD. The consolidation process accelerated by PVD with surcharge of 50 kPa was analysed using the ABAQUS software by adopting an elastic model. The aim of this study is to compare the settlement and the required time to fully consolidate the soft soil at different drain spacings (1.0 m, 1.5 m and 2.0 m) for two different thickness of the clay layer. The results shows that the time required to completely consolidate the soft soil for 12 m and 20 m thickness of clay layer with different spacings are in the range of 3 months to 66 months. The settlement rate and excess pore water pressure dissipation are increased when the spacing of the drain closer.
An Investigation on the Effect of Calcite Bacteria Seeding on Shear Strength of Peat Soil via an Unconfined Compression Test
Authors: Sidek Norbaya , Abdul-Talib S. , Mohd Zain N. , Rashid N.R.N.A. , Abu Bakar I.A.
Published: July 2015

Peat soils have been known for their problematic characteristics which include high water content, high compressibility and low shear strength. In this study, an attempt was made to investigate the effect of 1 week addition of modified Urea-CaCl2liquid medium with and withoutSporosarcina pasteuriion the shear strength of unsterilized dried peat soil using the Unconfined Compression Test. After the treatment period, significant increase in the shear strength of the soil was found to be highest for peat + medium at 42 kN/m2, moderate for peat + medium +Sporosarcina pasteuriiat 27 kN/m2and unchanged for peat + water control at 24 kN/m2. Although the growth dynamics of all the microbes involved in the calcite formation in the treated peat soil were not known, the addition of the modified Urea-CaCl2liquid medium into the soil clearly had contributed to the marked increased in the shear strength of the soil. It is probable that the medium had promoted a better growth of indigenous calcite bacteria population in the soil which may have been suppressed by the slow growingS. pasteuriipopulation being added daily to the soil
Bearing Capacity of Circular Footing on Sand Deposit
Authors: Marto Aminaton , Oghabi Mohsen , Mohd Yunus Nor Zurairahetty
Published: July 2015

Bearing capacity and settlement are two important parameters in geotechnical engineering. The bearing capacity of circular foundations on sandy soils is important to geotechnical practicing engineers. Design of foundations includes soil parameters and bearing capacity of foundation. This paper presents the results of laboratory experimental model tests of circular footings supported on sand deposit under static load. The finite element software Abaqus is used to compare the results. The effects of the relative density of the sand (30%, 50%, and 70%) and the diameter of circular footing (75 mm and 100 mm) are investigated. It can be concluded that the experimental test results fit quite well with the results of numerical method.
Groundwater Seepage Mapping Using Electrical Resistivity Imaging
Authors: Abidin Mohd Hazreek Zainal , Baharuddin Mohamad  Faizal Tajul , Zawawi Mohd Hafiz , Md Ali Nor’aishah , Madun Aziman , Ahmad Tajudin Saiful Azhar
Published: July 2015

In recent years, electrical resistivity method (ERM) has widely being applied as an alternative tool in engineering, environmental and archeological studies. A global image of groundwater seepage problem was difficult to obtained using conventional geotechnical method due to the efficiency of cost, time and result coverage. This study was conducted using electrical resistivity survey in order to investigate the potential of the problematic zone due to the groundwater seepage problem. ABEM SAS 4000 equipment set was used in during the resistivity data acquisition stage. Six (6) resistivity spread lines (SP) were performed across the slopes area using 2-D electrical resistivity imaging. The raw data was processed using RES2DINV and SURFER software for 2-D and 3-D subsurface image. Interpretation of electrical resistivity results was verified using the existing borehole and geochemistry results. Geochemistry results analyses were used Atomic Absorption Spectrometer (AAS) for determining cation and Ion Chromatography (IC) is for anions. Anion elements were studied consists of chloride, bicarbonate, nitrate and sulfate while cation elements consists of sodium, potassium, calcium and magnesium. All the elements were analyzed by using Piper Diagram to determine geochemistry facies in the groundwater. It was found that low resistivity value (ERV) which associated to groundwater (10 ~ 100 Ωm) can be found starts from the ground surface (0 m) to a greater (> 10 m) depth of the subsurface profile. The finding of the study water seepage can be categorized as Ca-HCO that indicator a typical of shallow fresh groundwater. The finding of the study is important to determine source process of water seepage on that area. This study has successfully demonstrates that the application of ERM with supporting borehole and geochemistry data was able to provide a comprehensive results due to the groundwater leakage detection.
Modelling of Clay Behaviour in Pile Loading Test Using One-Gravity Small-Scale Physical Model
Authors: Sulaeman Agus , Ling Felix N.L. , Sajiharjo Martosuro
Published: July 2015

The observations and tests under small scale in 1-gravity condition are intended to obtain a comparative behavior of a model and prototype of geotechnical case by imposing the scaling relations. Simulations to represent a related structure, sub-soil and failure mechanism need to be prepared prior to do observations in this modeling. To simulate pile loading test (PLT) on clay, the following models of: clay, pile, driving simulation and procedure of PLT based on ASTM D4410 were set-up. The PLT in reduced scale environment was then followed by performing normal practice of full scale PLT in original clay site. Load settlement curves obtained from both “pile loading test” in small and full scale simulations showed closely good agreement. Further observation and investigation on simulation of pile loading test in clay revealed that modeling the following: clay sub-soil resulted in new properties of clay, em=ep+λLn(N) which reflects stress scaling factor, N, pile size and pile driving hammer need scaling factor n and n3 respectively whereas PLT time needs time scaling factor, tp (n)0.5.
Position Control Mathematical Modelling and Operational Evaluation of Tele-Operated Electro-Hydraulic Actuator (T-EHA)
Authors: Yusof Ahmad Anas , Saadun Mohd Noor Asril , Mohamed Nor Mohd Khairi , Ibrahim Mohd Qadafie , Abdul Manaf Muhammad Zaidan
Published: July 2015

This study deals with a master-slave system for a tele-operated electro-hydraulic actuator (T-EHA) that focuses on a hydraulic system to remotely control a mini excavator. Tele-operation using such system is useful for tele-operation support of heavy construction and road restoration, typically in post-disaster areas. This paper presents the current development of position control electro-hydraulic actuator for such remote tele-operation application. A 2.4 GHz radio-controlled transmitter and receiver unit, which is also known as the master, has been utilized as the remote controller for an electro-hydraulic actuator. The electro-hydraulic actuator, which serves as the slave has been fabricated by using a tie-rod cylinder, and coupled with a 24 VDC electro-hydraulic valve. Position control mathematical modelling and operational evaluation have been studied with regard to the tele-operated electro-hydraulic actuator.
Surface Tension Effect on Sound Absorption Characteristics of a Cavity-Backed Semi-Permeable Membrane
Authors: Zainulabidin Muhd Hafeez , Wan L.M. , Ismail Al Emran , Kasron M.Z. , Kassim A.S.M.
Published: July 2015

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.
A Preliminary Study on Acoustical Performance of Oil Palm Mesocarp Natural Fiber
Authors: Abdul Latif Hanif , Yahya Musli Nizam , Rafiq Mohamed Najib , Sambu Mathan , Ghazali Mohd Imran , Mohamed Hatta Mohamed Nasrul
Published: July 2015

As the population increases, the demand of a comfortable environmental such as sound pollution is getting higher. Sound pollutions also have become worsen and creating concerns for many peoples. Due to this problem, synthetic materials as acoustic absorbers still applied as commonly acoustical panels and this material may hazardous to human health and contribute significantly a pollution to the environments. However, researchers have interested in conducting their research on natural fiber to be an alternative sound absorber. This study investigated the potential of oil palm Mesocarp fiber for sound absorbing material. The Mesocarp fibers were mixed with polyurethane (PU) as binder with ratio of 70:30. The thickness was varied in 10mm, 20mm, 30mm, and 40mm. This study also investigated the air gap of 5mm and 10mm in the sound absorption performance. Impedance Tube Method was used to measure sound absorption coefficient (a). The measurement was done on accordance with ASTM E1050-98, which is the standard test method for impedance and absorption of acoustical materials using a tube. The results showed that the optimum value for Mesocarp fiber is 0.93. The optimum value obtained at 5000 Hz. The influence of air gap increases the sound absorption especially from 250 Hz to 4000 Hz. These results indicate that fiber from Mesocarp is promising to be used sound absorbing material.
Parameter Optimization of Preheating Method on Aluminium-Stainless Steel Metal Inert Gas (MIG) Dissimilar Welding
Authors: Abdul Rahman Mohamad Rusdi , Ahmad Shah Luqman Hakim , Mahadzir
Published: July 2015

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.
A Comparison for the Simulation of Frictionless Contact Problem with Large Displacement
Authors: Nizam Z.M. , Obiya H. , Ijima K. , Azhar A.T.S.
Published: July 2015

Studies of contact problem have been widely executed by researchers with variable scopes, methods and definitions. A common problem occurs while handling contact phenomena is sliding through element boundary [1], due to the discontinuity of the local coordinate between elements and a contact point [2] [3]. The common problem that occurs at an element boundary is a stable convergence result is hard to achieve [4], thus inspires authors to make a comparison of two beam methods which are Euler-Bernoulli beam theory and Timoshenko beam theory for frictionless contact problem. Authors have been investigated geometrically non-linear analysis with extremely large displacements by using Tangent Stiffness Method (TSM) [5], a robust non-linear analysis method to execute analysis and produce results with high accuracy. In this study, authors propose the modification of the beam elements with three nodes by considering the adaptation of shear deformation by Timoshenko beam theory. The modification enables the contact point to slide through the element edge smoothly and some numerical examples are provided in this study.
Feasibility Study: Investigation of Polymer Nano-Composites (PNC) Material for Biomedical Application via Fused Deposition Modelling (FDM) Routes
Authors: Rahman M. Hashim , Yusof Mohd Sallehuddin , Ibrahim Mohd Halim Irwan , Osman S.A.
Published: July 2015

Polymer nanocomposites (PNC) have emerged as new materials which can show significantly enhanced mechanical properties over other polymer based materials through the addition of relatively small amounts of nanoscale additives. Rapid prototyping is impacting biomedical in several important ways. This research aims to investigate the potential of using new polymer nanocomposites (PNC) as a raw material for fused deposition modelling machine (FDM). Here, PNCs materials containing a polyamide (PA) and nanoparticles (<5wt%) will be synthesis by mechanical blending using twin extruder compounder to produce 0.85mm diameter of PNC. Dispersion analysis of the nanoparticles in the polymer matrix will be analyzed during the preparation and synthesis process. Futhermore, molecular binding and mixture structure will be investigated by using XPS analysis & Laser Raman Spectroscopy. Material will be characterized for their thermal properties using DSC and processed using FDM, the commercial rapid prototyping (RP) machine. The RP processing parameters will be established and used to produce test specimens to evaluate the mechanical properties of the PNC.
Properties of Steel Fiber Reinforcement Concrete with Different Characteristic of Steel Fiber
Authors: Shahidan Shahiron , Abdul Rahim Mustaqqim , Nik Zol Nik Suharliza , Azizan Muhammad Azizi , Ismail Isham
Published: July 2015

Currently in concrete technology a lot of materials were introduced to improve the quality and properties of concrete. Additional materials include the use of steel fibers into the concrete mix. With the used of steel fibers, it can enhance the strength of the concrete. In this research, two parameters will be investigated which is the volume friction of the steel fiber and the length of the steel fiber. End-hooked steel fiber with the length of 33 mm and 50 mm and the percentage of steel fiber 0.5 %, 1.0 % and 1.5 % used in this research. The size of the mold used is 100 mm x 100 mm x 100 mm. The characteristics during the fresh concrete were also investigated by conducting the slump test, compaction test and vebe test. All the samples has been cured in the water for 7th, 14th and 28th days for the compressive strength test. Based on result, it was concluded that the optimum percentage of steel fiber in this report was 1.0 % for the end-hooked steel fiber with 33 mm length which provided the highest compressive strength at 28 days.
Characterization of Carbon Brush from Coconut Shell for Railway Application
Authors: Ibrahim Mohd Halim Irwan , Said M.N. , Asmawi Rosli
Published: July 2015

Carbon brush has been developed for several decades for electric machines in microelectronic era. It is the electromechanical that connect the circuit to generate an electric motor. Mineral graphite always used as a raw material in producing carbon brush beside the uses of charcoal. This study is propose to use a coconut shell (CS) as waste material that can be recycle and sustainable to produce a carbon pre-cursor. This research is conducted to minimize the percentage of graphite or charcoal as a raw material in producing a carbon brush by replaced a CS as a raw material and produce a carbon brush for railway application. Several process such as baking, crushing, sieving, mixing, compacting and sintering are used in this study to produce a carbon brush. The formation of the carbon (C) had been produced by reaction of combustion in nitrogen atmosphere with 800°C temperature to produce carbon pre-cursor. The carbon brush sample then been prepared by mixing a copper powder and epoxy resin with different ratio of mixture. The suitable percentage of epoxy resin that could form a solid cylindrical shape was 15 %. Sample of carbon brush had been baked at 800°C to form the highest carbon. In this study, copper powder can produce a better conductivity where the sample can permit current flow through it. By using 60 % copper powder, the sample produce less porosity which resulted for high density. Lesser the pores of carbon brush sample produce low resistivity and high conductivity.
An Experiment Investigation of Film Cooling Effectivenes of Sister Hole of Cylindrical Shaped Hole Film Cooling Geometry on a Flat Plate Surface
Authors: Md Yazid Muhammad Haziq , Salleh Hamidon
Published: July 2015

Gas turbines are widely used nowadays for aircraft propulsion and in land-based power generation or in the industrial application. The operating temperature of gas turbine has to be increased in order to increase their effectiveness. Thus, a cooling method known as film cooling is introduced to cool down the high operating temperature of the gas turbine. Film cooling is one of the effective methods in reducing the heat load to a turbine airfoil. This method is cost effective and by far the most common and widely researched method in the industry. Film cooling effectiveness plays a vital role in modern gas turbine technology. This present study will focus on sister holes that are attached to the primary holes at shallow angle of 30°, with 4 different blowing ratios ranging from 0.5 to 2.0. The roles of the different in blowing ratios are to observe the different values of film effectiveness presented by the sister holes design and to select the most effective blowing ratio that suits the design at shallow angle. From the results obtained, the usage of sister holes with shallow angle further increases the film cooling effectiveness particularly at low blowing ratio.
Numerical Study of Flow Separation and Pressure Drop for Flow Past Staggered Tube Bundles
Authors: Sadikin Azmahani , Isa Norasikin Mat
Published: July 2015

The vertical single-phase flow was studied on the shell side of a horizontal tube bundle. In the present study, CFX version 14.0 from ANSYS was used to predict the flow regimes in the 19 mm diameter in staggered configuration with a pitch to diameter ratio of 1.32. The simulations were undertaken to inform on how the fluid flowed within the tube passages. The results show that the tube bundle arrangement in a heat exchanger does effect to the flow separation and re-attachment points. This is consistent with other published data.
Radiation Effects on Two-Dimensional MHD Falkner-Skan Wedge Flow
Authors: Abdulhameed M. , Saleh Habibi , Hashim Ishak , Roslan Rozaini
Published: July 2015

Radiation effects on two-dimensional MHD Falkner-Skan boundary layer wedge have been studied. Analytical solution of nonlinear boundary-layer equations is obtained by modified homotopy perturbation method. It is observed that the magnetic field tends to decelerate fluid flow whereas radiations and thermal diffusion tend to increase fluid temperature.
Fundamental Study of Dual Fuel on Exhaust Gas Recirculation (EGR) Operating with a Diesel Engine
Authors: Mat Yasin Mohd Hafizil , Paruka Perowansa , Mamat Rizalman , Ali Mohd Hafiz
Published: July 2015

In this paper, an experimental study evaluating the effect of exhaust gas recirculation (EGR) and liquefied petroleum gas (LPG) onboard systems attached to a single cylinder DI diesel engine running with diesel is presented. Tests were performed at the minimum (1400 rpm) and maximum engine speeds (4100 rpm). The engine were tested under four different operating modes mainly; (a) standard test condition, (b) engine with EGR system, (c) engine with LPG system and (d) the engine with EGR and LPG onboard systems. Parameters that been measured during the tests are percentage of oxygen (O2) content, carbon monoxide (CO) emissions, carbon dioxide (CO2) and unburned hydrocarbon (UHC) emissions. Results show for the exhaust emissions, the engine with LPG onboard system emits higher CO and UHC emissions for both engine speeds. According to the experimental results it can be concluded that the use of EGR system increased the exhaust gas temperature and CO2emissions. While the engine with EGR and LPG onboard systems have influenced much on the increase in CO and UHC emissions for both engine speeds.
Perforated Impact Strength of Woven Kenaf Fiber Reinforced Composites
Authors: Ismail Al Emran , Hasan Muhammad Aiman , Kamaruddin K.A.
Published: July 2015

This present work investigated the perforated impact strength of woven kenaf fiber reinforced composites subjected to different projectile velocities. Three layers of woven kenaf mats were stacked with four different fiber orientations 0, 15, 30 and 450. The composites are fabricated using hand-layout where the woven mats were placed into the mould with a polymeric resin. The wetted composites were compressed to squeeze out the excessive resin and to eliminate the void contents. The hardened samples were shaped into a standard geometry specified by ASTM D3763. Then, the composites were perforated impact using different speeds 1, 2 and 3 m/s. According to the present results, it was found that the perforated impact strength reduced when the impact velocity was increased. However, the impact strength of 150 oriented composite was higher when compared with other types of composites.
Influence of Ag on Chemical and Thermal Compatibility of LSCF-SDCC for LT-SOFC
Authors: Agun Linda , Abu Bakar Muhamad Subri , Ahmad Sufizar , Muchtar Andanastuti , Abd Rahman Hamimah
Published: July 2015

In addition to the good electrochemical performance criteria in solid oxide fuel cell (SOFC) applications, cathode material must match thermal expansion with other SOFC components. Thus, effects of Ag on thermal mismatch, chemical reactions, and microstructure are investigated. Ag (1 wt% to 5 wt. %) was mixed with La0.6Sr0.4Co0.2Fe0.8O3-δ (LSCF6428) and Sm-doped ceria carbonate (SDCC) composite cathode powder. LSCF6428-SDCC-Ag samples were sintered at 600 °C for 2 h. The thermal expansion coefficients (TECs), which were determined using a dilatometer, indicated relatively less TEC mismatch between LSCF-SDCC-Ag cathodes composite and SDCC electrolyte. The average TEC value obtained from 20 °C to 600 °C implied that LSCF-SDCC-A5 (5 wt. % Ag) showed better thermal matching (13.18×10−6 K−1) with SDCC electrolyte (12.84×10−6 K−1) and achieved better compatibility. The X-ray diffraction patterns indicated that the LSCF6428-SDCC-Ag peak increased with the increase in the amount of Ag. Scanning electron microscopy analysis showed that Ag was capable of maintaining the porosity that is required for cathodes (20%–40%). Results showed that Ag exhibited desirable thermal and chemical compatibility with LSCF-SDCC. Thus, LSCF6428-SDCC-Ag can be used as a composite cathode for low-temperature SOFCs.
Experimental Investigation on Ethanol-Petrol Blends Operating with a Petrol Engine: An Overview
Authors: Atan Nazrul , Mokhtar Azizul , Rahman Najib , Khalid Amir
Published: July 2015

The use of biopetrol fuel as alternative fuels in gasoline engine has been around for many years and Ethanol-petrol has the potential to be used as alternative fuel that can reduce the total CO2emission from internal petrol engine. However, the changes of bio-petrol is a very complex and need further understanding for researchers due to the relevance of the increase in the petroleum price and the future environmental regulation. This review paper focuses to ascertain a new approach in potential on ethanol-petrol blends operating with a petrol engine especially the effects of ethanol gas petrol blending ratio and variant types of ethanol on performance and emissions of petrol engine. It is shown that the variant in biopetrol blending ratio and engine operational condition are reduced engine-out emissions and increased efficiency. This paper presents on a review on three different types of ethanol like sugar cane, wheat and corn with various blended rates. Investigation framework study on how to complete the research is also included in this paper.Keywords: biopetrol, petrol engine, performance, emissions, biopetrol fuel properties
Spray Characteristic of Rapid Mixing Jatropha Oil Biodiesel in Burner System
Authors: Khalid Amir , Lambosi Latip , Suardi Mirnah , Amirnordin Shahrin Hisham , Zaman Izzuddin , Mansor Norani , Manshoor Bukhari
Published: July 2015

Jatropha Oil (JPO) is an alternative fuel proposed to be used especially for renewable sources and energy efficiency. Its characteristics need further investigation particularly for the use in an external burner system. The aim of this research is to investigate experimentally the spray characteristics of Jatropha oil in premixing injector for burner system. The Jatropha oil was blended with diesel at different ratio; JPO5, JPO10, and JPO15 at water content of W0, W5, W10 and W15. Fuel, water and air are injected in premix injector, causing the spray of these mixtures to produce lower toxic emission during combustion process. The spray angle, spray penetration length and spray area of different fuel-water ratio and equivalent ratio shall be analyzed from images captured using direct photography method with a DSLR camera. The result of the spray image will be further analyzed and compared between the different batches of image captured. It is shown that the effect of equivalent ratio and water content in fuel-water mixtures will give a significant effect on spray characteristics. Addition of water content will increases the viscosity of the mixtures, hence it increases the spray penetration length, spray area and reduce the spray angle.