- Department of Civil Engineering, Faculty of Engineering Building, University of Malaya, 50603 Kuala Lumpur, MALAYSIA
- Geotechnical Engineering, Earthquake Geotechnical Engineering, The best practices of coastal zone protection and conservation in spatial planning, Civil Engineering, Renewable Energy, Agricultural Engineering, and 5 moreBioenergy Systems, Biogas Plants, Energy Policy, Energy Economics, and Wood Technologyedit
In-situ dissipation tests provide a means of evaluating the in-situ horizontal coefficient of consolidation and horizontal hydraulic conductivity of marine clays. Dissipation tests by means of piezocone were utilised in the... more
In-situ dissipation tests provide a means of evaluating the in-situ horizontal coefficient of consolidation and horizontal hydraulic conductivity of marine clays. Dissipation tests by means of piezocone were utilised in the characterisation of the horizontal coefficient of consolidation and ...
Research Interests: Geology, Geotechnical Engineering, Clay Minerals, Geotechnical, Hydraulic conductivity, and 13 moreLand Reclamation, Dissipation, Energy Dissipation, Water Pressure, Pore Pressure, Consolidation of Structures In Situ, Piezometer, CharacterizationCharacterization, Mechanical Permeability, Marine Clays, Piezocone Dissipation, Surcharge Loading, and Pore Water Pressure
Ground improvement has been used on many construction sites to densify granular material, in other word to improve soil properties and reduce potential settlement. This paper evaluates the efficiency of rapid impact compaction (RIC),... more
Ground improvement has been used on many construction sites to densify granular material, in other word to improve soil properties and reduce potential settlement. This paper evaluates the efficiency of rapid impact compaction (RIC), which is an improvement on the process of deep dynamic compaction, in improving soil properties and controlling soil settlement. In this technique ground improvement is achieved by impacting the ground with a 7 ton weight, 35 times/min, and drop height of 0.8 m at 2.5 m c/c square grid spacing. Evaluation of improvement in soil properties was based on field data bycomparing pre-treatment and post-treatment cone penetrometer test (CPT) soundings. An interpretation of soil properties from CPT was made using interpretation software to assess the degree of improvement achieved. Load test was conducted to estimate soil settlement. It was found that the RIC succeeded in improving soil properties like relative density from 45 to 70%, increase the friction angl...
Research Interests: Engineering, Geotechnical Engineering, Water Pollution, In-situ mechanical testing, Physical sciences, and 10 morePhysical properties of foods, Groundwater Quality, Soil Compaction, Cone Penetration Test, Compaction, DIRECT SHEAR TEST ON GRANULAR SOILS, Performance of soil instrumentation on settlement prediction, Improvement Depth, Rapid Impact Compaction (RIC), and Penetration test
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Research Interests: Environmental Science, Soil Science, Highway engineering, Peatland Ecology, Removal Of Heavy Metals In Contaminated Soils, and 15 moreMultidisciplinary, Peat, Compressive Strength, Laboratory Testing of Geomaterials, Applied Sciences, Highway Construction Management, Stabilization and Reconstruction, Coke fired blast furnaces, Compressive Strength and Workability of Concrete Using Natural Pozzolana as Partial Replacement of Ordinary Portland Cement, Peat Soil, Siliceous Sand, Unconfined Compressive Strength, Stabilized Soils, Initial Permeability, and Slags
Research Interests: Civil Engineering, Geology, Chemistry, Peat, Cement, and 7 moreMicrostructural Characterization of Clays and Silts stabilized with chemicals and pozzolanic admixtures, Water Content, Tropical Lowland Peats, Peat Stabilization, Sand Filler, Tobomerite Gel, and Bulletin of Engineering Geology and the Environment"
Peat classification methods for engineering purposes and the main factors and aspects of these classification systems are discussed. Among the factors that enter into the classification of tropical lowland peats are the organic content... more
Peat classification methods for engineering purposes and the main factors and aspects of these classification systems are discussed. Among the factors that enter into the classification of tropical lowland peats are the organic content and degree or level of humification (on the von Post scale). The organic content as a percentage of the total content determines whether an organic soil is classified as a slightly organic soil (3-20 % organic content), an organic soil (20-75 % organic content), or a peat (more than 75 % organic content). The ASTM standard method of classifying peat is outlined in the Standard Classification of Peat Samples by Laboratory Testing (ASTM D 4427), which includes the use of the ASTM D 5715 (fiber content by field testing for degree of humification) field test method. The von Post humification test (von Post classification system) involves squeezing the peat and the material that is extruded between the fingers, examining the material, and classifying the soil as belonging to one of ten (H1-H10) humification or decomposition categories. Peats are then further subdivided into fibric or fibrous peats (humification range of H1-H3), hemic or moderately decomposed peats (H4-H6), or sapric or amorphous peats (H7-H10). The classification of organic soil or peat for engineering purposes mainly involves using the ignition test (ASTM D 2974) to determine the organic content or determining the percentage of organic content lost on ignition.
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Field observations on physico-chemical characteristics of water and sediment quality were carried out from March, 2005 to Dec, 2005 at 4 different stations (Station 1 – Main Jetty Pulau Tuba, Station 2 – Pulau Tuba Jetty number 2, Station... more
Field observations on physico-chemical characteristics of water and sediment quality were carried out from March, 2005 to Dec, 2005 at 4 different stations (Station 1 – Main Jetty Pulau Tuba, Station 2 – Pulau Tuba Jetty number 2, Station 3 – Simpan Tiga Mangrove Area and Station 4 – Kuah Jetty) along the coastal waters iin Pulau Tuba, Langkawi. The physico-chemical parameters such as temperature (27.43–28.88°C), DO (3.79–6.49 mg/l), pH (7.72–8.20), salinity (33.10–33.96 ppt), TDS (32.27–32.77) g l−1) and specific conductivity (49.83-51.63 mS cm−1) did not show much variation among the stations. While nitrate, nitrite and phosphate were found among the stations, their concentrations varied and ranged from 2.04–26.93 μ g N l−1, 0.86–4.03 μ g N l−1 and 0.27–1.33 μ g P l−1, respectively. Although the textures of the bottom sediment were limited to sand, silt and clay, most of the stations were dominated by black clay with the highest amount (82.97%) being found at station 4. The amount...
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Research Interests: Engineering, Mechanical Engineering, Applied Mathematics, Soil Mechanics, Deep excavation and urban tunnelling, and 11 moreMeasurement, Stiffness, Tri-Axial Accelerometer, Excavations, Unloading Scarp, Hardening Soil Model, Kenny Hill Formation, Oedometer Stiffness, Standard Penetration Test, Hardening Soil Models, and Oedometers
Research Interests: Engineering, Ecological Engineering, Earth Sciences, Environmental Science, Ecosystems Ecology, and 15 moreHydrology, Addiction and Recovery, Climate Change and coastal zones, Coastal Zone Management, Environmental Sciences, Habitat Restoration, Forest ecosystems, Environmental Degradation and Sustainable Development Imacts and Response, Degradation, Avicennia marina, Connectiviy in corals of west coast of Mexico, Conifer tree seedlings, Breakwater, Avicennia Alba, and Detached Breakwater
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ABSTRACT In slope engineering, soils are ordinarily in an unsaturated state. Today the application of unsaturated soil mechanics theory to slope stability analysis has become an essential point in geotechnical engineering research. To... more
ABSTRACT In slope engineering, soils are ordinarily in an unsaturated state. Today the application of unsaturated soil mechanics theory to slope stability analysis has become an essential point in geotechnical engineering research. To explain the relationship between matric suction and soil structure with slope stability (via the pulling-out effect), reasonable finite-element (FE) modules can be created. By using FE analysis (which includes the existing soil parameters), the stability of residual soil slope can be simulated under different water contents (via changes in matric suction) and soil structures (via different phi values). Inferring from the soil-water characteristic curve obtained from previous work, the influence of matric suction on unsaturated soil slope is determined. The importance of matric suction and soil structure is discovered during the root pulling-out analysis. The results show that because of increasing matric suction in unsaturated soil (which is the result of the decreasing degree of saturation), the required force during the pulling-out process (root anchorage) and consequently stress-distribution capacity will be increased, and the safety factor of the soil slope is amended. However, changes in soil friction angle do not affect root anchorage in roots with a sharp deviation angle (53 degrees); for a root with a steep deviation angle (15 degrees), as the soil structure improves by means of increases in the internal friction angle, the forces needed to determine the pull out angle, and accordingly, the stress-distribution capacity, are modified, and the safety factor is improved.
Research Interests: Civil Engineering, Geology, Finite Element Methods, Geomechanics, Soil Mechanics, and 15 moreSlope Stability, Finite element method, Removal Of Heavy Metals In Contaminated Soils, Finite Element Analysis, Geotechnical Properties of Residual Soils, Friction Stir Welding, Soil Structure Interaction, Identification Workplace Hazards at a Production Line in a Factory and Job Safety and Health Protection for Workers, Finite Element Simulations, Soil and rock slope stability analysis, Dispersion and Bioremediation of PAHs In a Saturated and Unsaturated Porous Medium, Degree of Saturations, Different Water Contents, Internal Friction Angle, and Slope Protection
The Environmental Impact Assessment (EIA) procedure in Malaysia has been developed primarily as an aid to the environmental planning of new or existing development projects. The pollution control which have been promoted for quite some... more
The Environmental Impact Assessment (EIA) procedure in Malaysia has been developed primarily as an aid to the environmental planning of new or existing development projects. The pollution control which have been promoted for quite some time in Malaysia is essentially a curative process where else the implementation of the mandatory EIA procedures is more of a preventive measure to avoid costly mistakes in planning and development. All activities listed under the Environmental Quality (Prescribed Activities) (Environmental Impact Assessment) Order 1987 have to undergo an EIA before commencement of work. This paper describes the EIA process in Malaysia with a particular reference to a proposed new road which has undergone an EIA study. The EIA procedure as outlined in the Environmental Quality Act, Malaysia (1974) is discussed and several aspects of the EIA process is highlighted.
Research Interests: Environmental Engineering, Project Management, Environmental Planning and Design, Urban Planning, Malaysia, and 6 moreDeveloping Countries, Environmental Impact Assessment, Environmental Pollution and Control Technology, Environmental Impact, Climate Change Effects on Social and Economic Aspects, and Work place bullying laws and legislation
Research Interests: Mathematics, Removal Of Heavy Metals In Contaminated Soils, Multidisciplinary, Applied Sciences, Bearing Capacity, and 11 moreLaminar Non Premixed Hydrocarbon Flame, DESIGN OF PROVING RING, Peat Soils, Thixotropic Binders, Sustainable New Binder-based Composites, Curing Time, Deep Mixing Method, Mixing Auger, Prebored Premixed, Cone Penetrometers, and Augers
Peaty soils are not suitable as foundation soils as they are weak and highly compressible. This paper describes a study on peat soil stabilisation to improve its physical and engineering properties. It investigates the effect of additives... more
Peaty soils are not suitable as foundation soils as they are weak and highly compressible. This paper describes a study on peat soil stabilisation to improve its physical and engineering properties. It investigates the effect of additives (binder amount 5%, 10% and 15% (85% ...
Research Interests: Drying Technology, Feed additives in poultry nutrition, Compressive Strength, Cement, Bentonite, and 15 moreIce, Compressibility, Dry Density, Food Additives, Compaction, Bearing Capacity, Cement and Concrete Materials, Humid Tropics, Chemical Stabilization, Additive Contents, Cement Additives, Dry Densities, Engineering Properties, Foundation Soils, and California Bearing Ratio
Research Interests: Civil Engineering, Plasticity, Composite Materials and Structures, Composites, Composite Materials, and 15 moreRemoval Of Heavy Metals In Contaminated Soils, Adhesives For Paleontological Conservation, Phenotypic Plasticity, Geotechnical Properties of Residual Soils, Building, Cement, Crops, Cements, Residual Stress of Soils, Luting Cements, Moisture Content, Construction Building, Adhesives, Chemical Stabilization, and Granite Soil
Typically, most of the commercially available GaN-based LEDs (Light Emitting Diodes) are grown on sapphire as their substrates. Due to the insulating substrate, lateral current injection is employed so that the anode and cathode contacts... more
Typically, most of the commercially available GaN-based LEDs (Light Emitting Diodes) are grown on sapphire as their substrates. Due to the insulating substrate, lateral current injection is employed so that the anode and cathode contacts are in side-by-side configuration. During the etching process, the possibility of slanted mesa sidewall to form is higher. In this work, the influence of slanted mesa sidewall are studied while its light emitting area size and contacts position are maintained. The comparison for optical output power, current-voltage, thermal dissipation and distribution characteristics of different angles of slanted mesa sidewall are performed. Angles of slanted mesa sidewall are varied from angle-in and angle-out with reference to 90° at mesa edge. The simulation results revealed that with the increment of slanted angle, the LEDs performed better due to improved overall emission intensity and uniform current distribution of the devices. The angled sidewalls efficiently deflect photons that are initially guided laterally within the GaN epilayer in the off-surface direction. As such, devices showed better overall performance.
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Research Interests: Microstructure, Modeling, Peatland Ecology, Removal Of Heavy Metals In Contaminated Soils, Physical Education, and 35 moreSport, Soil Cementation, Soil Investigation and Testing, Mechanical properties, Exercise Science, Strength and Conditioning, Compressive Strength, Energy Dispersive X-Ray Analysis, Strength of materials, Phase Field Models, Stabilisation, Construction techniques of Roman roads, Binder, Cements, Engineering/mechanical Properties of Rocks, Microstructures, Shear Strength, Bearing Capacity, Shear Bond Strength, Peat Soils, Mixed Method, Peat Soil, Test Results, Deep Mixing Method, Binders, Concrete Mixing, Geologic Models, Cement Column Methods, Curing Times, Deep Mixing Methods, Scanning Electron Micrographs, Unconfined Compressive Strengths, Undrained Shear Strengths, Undrained Test, and Unconfined Compression Strength
... REFERENCES 1. Megat Johari Megat Mohd Noor, Abang Abdullah Abang Ali, Mohd Rasid Osman, Mohd Sapuan Salit, Norman Mariun, Mohd Saleh Jaafar, Abdul Halim Ghazali, Husaini Omar & Rosnah Mohd Yusuff (2001) A... more
... REFERENCES 1. Megat Johari Megat Mohd Noor, Abang Abdullah Abang Ali, Mohd Rasid Osman, Mohd Sapuan Salit, Norman Mariun, Mohd Saleh Jaafar, Abdul Halim Ghazali, Husaini Omar & Rosnah Mohd Yusuff (2001) A New Engineering Education Model For Malaysia. ...
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ABSTRACT This was a localized study of the freshwater lenses at Carey Island, Selangor, Malaysia. Changes to morphology of the lenses were determined via Time-Lapse Resistivity Tomography (TLERT) images, borehole data, geological... more
ABSTRACT This was a localized study of the freshwater lenses at Carey Island, Selangor, Malaysia. Changes to morphology of the lenses were determined via Time-Lapse Resistivity Tomography (TLERT) images, borehole data, geological formation history, correlation between groundwater geochemistry and subsurface resistivity, and hydraulic conductivity data. Subsurface resistivity changes were measured by ABEM Terrameter SAS4000 and ES10-64 electrode selector. TLERT monitoring during tide regression produced resistivity images that showed adjacent zones of thin and thick layers of freshwater lenses existing along 400m of resistivity-survey line. Analysis of particle distribution discovered various hydraulic conductivity values that were due to heterogeneous alluvium Quaternary sediments. The freshwater lenses were found to be thinner in high-hydraulic-conductivity soil. Gula Formation’s various hydraulic conductivities effected the morphology changes, which were drastic and distinct during high-tide regression, indistinct during low tide. The lenses were also thinner in dry season, making season also an influencing factor. The study’s results allow strategising of sustainable groundwater exploration at limited-recharge areas.
Research Interests: Data Compression, Change Laboratory method, Computer Simulation, Compression, Luting Cements, and 15 moreFluride Content in Ground Water, Curve fitting, Coke fired blast furnaces, Como Mejorar La Resistencia Del Cemento Portland Al Ataque Por Dioxido De Carbono, Dairy Herd Management by Laboratory Method, Intrinsic Compressibility, Furnaces, Consolidation of Structures In Situ, Coefficient of Vertical Conslidation, Deep Soil Stabilization, Fibrous Peat, Cement Manufacture, Compression Curves, Compression Rates, and Ground Granulated Blast Furnace Slag
Deep stabilized peat columns could be considered as attractive and economical foundation for construction of highway embankments on deep peat ground. However, peat itself is very problematic and failure in the formation of the columns... more
Deep stabilized peat columns could be considered as attractive and economical foundation for construction of highway embankments on deep peat ground. However, peat itself is very problematic and failure in the formation of the columns with adequate strength was often attributed to ...
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Scientific Research and Essays Vol. 6(8), pp. 1732-1739, 18 April, 2011 Available online at http://www.academicjournals.org/SRE ISSN 1992-2248 ©2011 Academic Journals ... Sadek Deboucha1*, Roslan Hashim1 and Azlan A. Aziz2 ... 1Department... more
Scientific Research and Essays Vol. 6(8), pp. 1732-1739, 18 April, 2011 Available online at http://www.academicjournals.org/SRE ISSN 1992-2248 ©2011 Academic Journals ... Sadek Deboucha1*, Roslan Hashim1 and Azlan A. Aziz2 ... 1Department of Civil Engineering, ...
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... ISBN Number: 0-582-30094-0 Dhowian, AW and TB Edil, 1980. Consolidation behavior of peats. Geotech. ... Influence of the nature of organic compounds on fine soil stabilization with cement. Can. Geotech. ... Behavior of stabilized peat... more
... ISBN Number: 0-582-30094-0 Dhowian, AW and TB Edil, 1980. Consolidation behavior of peats. Geotech. ... Influence of the nature of organic compounds on fine soil stabilization with cement. Can. Geotech. ... Behavior of stabilized peat soils in unconfined compression tests. Am. ...
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Abstract A time-lapse resistivity measurement was used to study the effect of salinity to groundwater aquifers at ex-promontory land of Carey Island in Malaysia. Resistivity was measured through an ABEM Terrameter SAS 4000, combined with... more
Abstract A time-lapse resistivity measurement was used to study the effect of salinity to groundwater aquifers at ex-promontory land of Carey Island in Malaysia. Resistivity was measured through an ABEM Terrameter SAS 4000, combined with ES 10-64 electrode ...
Research Interests: Soil Stabilization, Silica, Soft Soil, Soil Type, Sustainable New Binder-based Composites, and 8 moreCement and Concrete Materials, Como Mejorar La Resistencia Del Cemento Portland Al Ataque Por Dioxido De Carbono, Portland cement, Ground Granulated Blast furnace Slag (GGBFS), Peat Soil, Siliceous Sand, Unconfined Compression Strength, and Ground Granulated Blast Furnace Slag
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Corresponding Author: Babak Kamali, Institute of Ocean and Earth Sciences (IOES), University of Malaya, 50603 Kuala Lumpur, Malaysia Tel: 0060379676855 Fax: 0060379676994 E-mail: b_kamali@perdana.um.edu.my E-mail: kamali_babak@hotmail.com... more
Corresponding Author: Babak Kamali, Institute of Ocean and Earth Sciences (IOES), University of Malaya, 50603 Kuala Lumpur, Malaysia Tel: 0060379676855 Fax: 0060379676994 E-mail: b_kamali@perdana.um.edu.my E-mail: kamali_babak@hotmail.com 2817
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Research Interests: Soil Mechanics, Slope Stability, Peatland Ecology, Removal Of Heavy Metals In Contaminated Soils, Soil Cementation, and 15 moreSoil Stabilization, Roman Limes, Construction techniques of Roman roads, Peat Soils, Case Histories, Seashell in Concrete Mixing, Cement and Concrete Materials, Peat Soil, Deep Mixing Method, Deep Mixing Methods, Academic Literatures, Cement Columns, Comprehensive Reviews, Deep Soil Stabilizations, and Soil Stabilizations
... 2.4.4. Oedometer consolidation apparatus Standard oedometer consolidation tests were performed on both undisturbed peat and stabilized peat cured after ... that formation of cementing products in the soil was not retarded by the... more
... 2.4.4. Oedometer consolidation apparatus Standard oedometer consolidation tests were performed on both undisturbed peat and stabilized peat cured after ... that formation of cementing products in the soil was not retarded by the presence of organic matter in peat due to ...
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Climate Change and Mangroves on the West Coast of Peninsular Malaysia: Threats and Adaptation
Coastal hydrodynamics related to wave, current and wave-current interactions are important for many coastal engineering design and application. They allow the study of new engineering methods for coastal defense and play an essential role... more
Coastal hydrodynamics related to wave, current and wave-current interactions are important for many coastal engineering design and application. They allow the study of new engineering methods for coastal defense and play an essential role in the calculation of sediment transport and morphological evolution. Prediction of hydrodynamic associated with coastal structures has been largely relied on the empirical relation in the last 28 years supported by physical tests. Due to recent advances in the computer power and development experienced by numerical models, use of a number of coastal hydrodynamic modeling has become a promising alternative to predict coastal hydrodynamic and the most feasible approach to solve the hydrodynamic problems. However, the simulation results produced by these models depends on model concepts used; consideration of hydrodynamic processes such as wind shear, wave forces, wave transformation (breaking, shoaling, roller effect, diffraction, transmission), tid...
Marine renewable energy (MRE) is yet to be included in the Feed-in Tariff (FiT) system in Malaysia. However, the country is surrounded by the Straits of Malacca and South China Sea, making it suitable to harness energy in the water.... more
Marine renewable energy (MRE) is yet to be included in the Feed-in Tariff (FiT) system in Malaysia. However, the country is surrounded by the Straits of Malacca and South China Sea, making it suitable to harness energy in the water. Financial supports from the government are essential in developing this technology. This paper aimed to suggest appropriate FiT rates of MRE based on Net Present Value (NPV) approach. Meanwhile, the proposed FiT rates were compared with other implemented FiT rates of MRE in United Kingdom, Germany, France, Republic of Ireland, Italy, Portugal and Korea. The results showed that reasonable FiT rates of MRE in Malaysia should be in the range of 0.06-0.60/kWh depending on the type of MRE technology used. The proposed tariffs were exceedingly higher than the implemented FiT rates of solar photovoltaic ranging from (sic)0.20 to 0.28/kWh due to higher project cost. (C) 2015 Elsevier Ltd. All rights reserved. Link to Full-Text Articles : http://www.sciencedirect.com/science/article/pii/S1364032115003445 http://ac.els-cdn.com/S1364032115003445/1-s2.0-S1364032115003445-main.pdf?_tid=93fc1d02-4010-11e5-af14-00000aacb35e&acdnat=1439287745_b79a178ccb53418bdfc10827036f0298
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ABSTRACT The discharge coefficient of a modified triangular side weir is analyzed regarding various non-dimensional input sets. It is desirable to select and analyze factors or parameters that are truly relevant or the most influential to... more
ABSTRACT The discharge coefficient of a modified triangular side weir is analyzed regarding various non-dimensional input sets. It is desirable to select and analyze factors or parameters that are truly relevant or the most influential to triangular side weir discharge coefficient estimation and prediction. The Adaptive Neuro-Fuzzy Inference System (ANFIS) is applied for the selection of the most prominent triangular side weir discharge coefficient parameters based on ten input parameters. The input variables were searched using the ANFIS network to specify the input parameters’ effects on the discharge coefficients. According to the obtained results, the side weir included angle has the most effect on modeling the discharge coefficient. Then by using the selected input variables, the discharge coefficient was modeled with ANFIS, artificial neural network, support vector machine and multi non linear regression methods. The results show that ANFIS could predict the discharge coefficient significantly better than the other investigated models.
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ABSTRACT The adaptive neuro-fuzzy inference system (ANFIS) is applied for selection of the most influential reference evapotranspiration (ET0) parameters. This procedure is typically called variable selection. It is identical to finding a... more
ABSTRACT The adaptive neuro-fuzzy inference system (ANFIS) is applied for selection of the most influential reference evapotranspiration (ET0) parameters. This procedure is typically called variable selection. It is identical to finding a subset of the full set of recorded variables that illustrates good predictive abilities. The full weather datasets for seven meteorological parameters were obtained from twelve weather stations in Serbia during the period 1980–2010. The monthly ET0 data are obtained by the Penman–Monteith method, which is proposed by Food and Agriculture Organization of the United Nations as the standard method for the estimation of ET0. As the performance evaluation criteria of the ANFIS models the following statistical indicators were used: the root mean squared error (RMSE), Pearson correlation coefficient (r) and coefficient of determination (R2). Sunshine hours are the most influential single parameter for ET0 estimation (RMSE = 0.4398 mm/day). The obtained results indicate that among the input variables sunshine hours, actual vapor pressure and minimum air temperature, are the most influential for ET0 estimation. The maximum relative humidity and maximum air temperature are the most influential optimal combination of two parameters (RMSE = 0.2583 mm/day).
Research Interests: Engineering, Partial Differential Equations, Soil Science, Soft Computing, Turkey, and 12 moreSoil and Water Engineering, Feature Selection, Business Models, Variable Selection, Evapotranspiration, adaptive neuro fuzzy inference system (ANFIS), Adaptive Neuro-Fuzzy Inference Systems, Artifical Neural Network(ANN), Coral Reef Skeleton as Database of Climatic Changes, Country Northern Spain, Reference Evapotranspiration, and Daily Pan Evaporation
ABSTRACT Visitors utilize the urban space based on their thermal perception and thermal environment. The thermal adaptation engages the user’s behavioural, physiological and psychological aspects. These aspects play critical roles in... more
ABSTRACT Visitors utilize the urban space based on their thermal perception and thermal environment. The thermal adaptation engages the user’s behavioural, physiological and psychological aspects. These aspects play critical roles in user’s ability to assess the thermal environments. Previous studies have rarely addressed the effects of identified factors such as gender, age and locality on outdoor thermal comfort, particularly in hot, dry climate. This study investigated the thermal comfort of visitors at two city squares in Iran based on their demographics as well as the role of thermal environment. Assessing the thermal comfort required taking physical measurement and questionnaire survey. In this study, a non-linear model known as the neural network autoregressive with exogenous input (NN-ARX) was employed. Five indices of physiological equivalent temperature (PET), predicted mean vote (PMV), standard effective temperature (SET), thermal sensation votes (TSVs) and mean radiant temperature (T mrt) were trained and tested using the NN-ARX. Then, the results were compared to the artificial neural network (ANN) and the adaptive neuro-fuzzy inference system (ANFIS). The findings showed the superiority of the NN-ARX over the ANN and the ANFIS. For the NN-ARX model, the statistical indicators of the root mean square error (RMSE) and the mean absolute error (MAE) were 0.53 and 0.36 for the PET, 1.28 and 0.71 for the PMV, 2.59 and 1.99 for the SET, 0.29 and 0.08 for the TSV and finally 0.19 and 0.04 for the T mrt.
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Prediction of the wake structure is important to understand the lee flow of a tidal current turbine. The proposed analytical wake model consists of several equations derived from the theoretical works of a ship propeller jet. Axial... more
Prediction of the wake structure is important to understand the lee flow of a tidal current turbine. The proposed analytical wake model consists of several equations derived from the theoretical works of a ship propeller jet. Axial momentum theory was used to predict the minimum velocity at the immediate plane of the lee wake and followed by the proposed recovery equation to determine the minimum velocity at various lateral sections along the rotation axis. Gaussian probability distribution was used to predict the velocity distribution of lateral sections in a wake. Entire wake is able to be illustrated through the calculation of the efflux equation, recovery equation and lateral distribution equations. Authors' previous works proposed a simplified one-dipped velocity profile and this works were being extended to predict the two-dipped velocity profile with the consideration of hub effects. The wake model is validated by using the well-accepted experimental measurements and the goodness-of-fit test. The results demonstrated that the wake model is able to predict the wake profile under various ambient turbulence conditions of TI (turbulence intensity) = 3%, 5%, 8% and 15%. (C) 2014 Elsevier Ltd. All rights reserved. http://www.sciencedirect.com/science/article/pii/S0360544214013024
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Ultrasonic pulse velocity is affected by defects in material structure. This study applied soft computing techniques to predict the ultrasonic pulse velocity for various peats and cement content mixtures for several curing periods. First,... more
Ultrasonic pulse velocity is affected by defects in material structure. This study applied soft computing techniques to predict the ultrasonic pulse velocity for various peats and cement content mixtures for several curing periods. First, this investigation constructed a process to simulate the ultrasonic pulse velocity with adaptive neuro-fuzzy inference system. Then, an ANFIS network with neurons was developed. The input and output layers consisted of four and one neurons, respectively. The four inputs were cement, peat, sand content (%) and curing period (days). The simulation results showed efficient performance of the proposed system. The ANFIS and experimental results were compared through the coefficient of determination and root-mean-square error. In conclusion, use of ANFIS network enhances prediction and generation of strength. The simulation results confirmed the effectiveness of the suggested strategies.
Research Interests: Materials Engineering, Mechanical Engineering, Prediction, Ultrasound, Acoustic Emission, and 15 moreCost Estimation, Porosity and Permeability in Reservoirs, Classical Physics, Ground improvements, Compressive Strength, High Strength and High Performance Concrete, Ultrasonics, Fly Ash, Mortars, Peat Extraction, Multiple Choice Tests, Ultrasonic Sensor, Peat Soil, Parameters for Site Analysis, and Ultrasonic Pulse Velocity
Chemical stabilization as a fast technique to improve the soil properties.Utilization of waste materials to enhance the soil is viable.Pulverized fuel ash (PFA) is a waste by-product of coal power plants.Adaptive neuro-fuzzy (ANFIS)... more
Chemical stabilization as a fast technique to improve the soil properties.Utilization of waste materials to enhance the soil is viable.Pulverized fuel ash (PFA) is a waste by-product of coal power plants.Adaptive neuro-fuzzy (ANFIS) computing technique.Unconfined compressive strength estimation of PFA–cement–sand mixture.The paper addresses the application of an adaptive neuro-fuzzy (ANFIS) computing technique to predict the unconfined compressive strength of the pulverized fuel ash–cement–sand mixture. A series of unconfined compressive tests were performed on several mixtures of cement, pulverized fuel ash (PFA), and sand for checking and training data for the ANFIS network. Although some mathematical functions were applied to model the unconfined compressive strength of the construction materials, numerous setbacks of the models were observed. The artificial neural network (ANN) can be used as an analytical method for various prediction purposes because it provides the benefit of independency on the knowledge of internal system parameters, compressed compact solution in terms of multi-variable problems and rapid computation. The ANFIS is a particular class of the ANN family with attractive estimation and learning potentials. This provides a suitable platform when the analysis is aimed to counter the uncertainties in a system. The ANFIS RMSE was 0.0617 for prediction of the unconfined compressive strength of the pulverized fuel ash–cement–sand mixture.