bluuebunny/crossref_metadata_2025 huggingface dataset:
Analysis of the Success Factors and Failure Causes in Projects
Authors: Montequín Vicente Rodríguez , Fernández Sonia Cousillas , Fernández Francisco Ortega , Balsera Joaquín Villanueva
Published: January 2016

Projects are complex works subjected to significant time, budget and quality constraints. One or the greatest challenges in project management still remaining unsolved is determining what is necessary to do in order to achieve success or failure. According to the specialized literature, both concepts of success factors and failure causes in projects are largely subjective and therefore difficult to quantify, depending on the point of view of the stakeholders involved. This paper compares which are the most frequent failure causes and the most important success factors among three different scenarios: for any type of project, for ICT projects and for ICT projects carried out in Spain only, by means of a worldwide empirical survey carried out among project managers intended to gather their personal perceptions on the matter. The survey is based on a questionnaire anonymously distributed through a professional internet network.
Job Shadowing in Information Technology Projects
Authors: Sohani Shrihari S.
Published: January 2016

High-value turnkey projects in Information Technology firms are susceptible to multiple risks. Inappropriate staffing is one of the major risks that can impact deliverable negatively. The greatest fallacy that comes up is the incongruence between HR managers and line managers while staffing critical experience based roles. HR managers being aligned with the firm's strategy to maintain a low resource bench figure are driven to staff these positions with less than suitable resources from the firm's internal labor market. The line manager under pressure to deliver on time and budget need resources with appropriate skills and experience and hence are not averse to hire from external labor market. This incongruence in goals creates friction between HR and line manager. The research paper presents a framework to balance the twin priorities of HR and line manager and also assist in creating a human resource-based non-replicable strategic advantage for the IT firm.
Future of Smart Cities in the Knowledge-based Urban Development and the Role of Award Competitions
Authors: Shaqrah Amin A.
Published: January 2016

This study investigates the role of King Abdullah II award for excellence in government performance and transparency in the making of a successful smart city. In order to achieve a better view to support smart city initiatives process and validate the research, the study conducted several interviews with all mangers of Amman municipality directorate to collect the primary data of this study. Further, a qualitative research was performed. Having reviewed the existing literature, Researcher determined the role of knowledge based urban development as a new paradigm in managing urban planning and development in order to ensure Amman city is competitive in the global market. The results concluded that greater Amman municipality applied sufficient knowledge, technology, infrastructure, skills and leadership to winning at King Abdullah II award for excellence. In the light of the literature and case findings, the paper provides recommendations for the Amman municipality and to Arab regions that are working hard to develop smart cities and seeking a global recognition.
When Innovation Stumbles
Authors: Van Cauter Lies , Bannister Frank , Crompvoets Joep , Snoeck Monique
Published: January 2016

Catalogues of failure factors and descriptive accounts of failures are relatively easy to find in the information systems (IS) literature as are studies of IS success or technology adoption. In contrast, in-depth studies of failure are rare. What is more, most of the research into IS failure and success uses a positivist approach - two widely cited examples of the latter being the Delone and McLean IS success model and the Unified Theory of Acceptance and Use of Technology. Given this, an interesting question is whether an interpretivist approach can uncover aspects and causes of failure that might not be visible when viewed through a positivist lens. This paper seeks to answer this question by examining a failed e-government system in Flanders (Belgium) using Sauer's Information Systems failure process model. The analysis suggests that this model, and more generally an interpretivist approach, can provide a richer and more insightful understanding of the causes and the process of failure.
Robust Option through Binomial Tree Method
Authors: Hanafizadeh Payam , Qahi Amir Hossein Mortazavi , Ponnambalam Kumaraswamy
Published: January 2016

This study proposes a robust approach for pricing a European option using the binomial tree method. This method considers stock up and down prices in a closed and convex region, called the uncertainty region, defined by the covariance matrix of high and low stock prices. The option model uses this uncertainty region for pricing instead of spot prices. The method proposes an interval of prices for an option considering incidences of the worst and the best states of the stock price. The interval is flexible as it takes into account the covariance of the historical data of a stock's high and low prices and the radius of an uncertainty region.
A Knowledge Management Approach to the Loosely Coupled Systems
Authors: Agrez Jernej , Damij Nadja
Published: January 2016

The purpose of the research is to explore characteristics and design the concept of the knowledge management system that would be able to operate in a loosely coupled system. We used a literature review to determine characteristics of the conceptual design that would fit into the unstable organizational environment. Based on the theoretical insights, we designed the open framework that is capable of adjustments, multilevel designing, it allows integration of statistical methods and supports conversion into the web ontology language. We applied developed concept to a loosely coupled system test case, to achieve better understanding of its capabilities. The solution is appropriate for implementation to analyze knowledge network and process architecture relations in different informal organizational networks, as well as during events where spontaneous cooperation among different types of organizations and individuals is necessary, such as massive natural disasters and other simila events.
Numerical Investigation of Heat Transfer Enhancement in Adsorbed Natural Gas Storage under the Dynamic Conditions
Authors: Ybyraiymkul D.T. , Kaltayev A. , Ng Kim Choon
Published: January 2016

Natural gas, from the environmental point of view, is the cleanest fuel after hydrogen. Widespread use of gaseous fuel is restricted by its storage problems in containers under high pressure (20-25 MPa) or liquefied gas at low temperatures (-163 °C). One of the most promising solutions to such problems (high pressure and low temperature) is to develop a vessel based on adsorption technology, designed for efficient storage of natural gas at relatively low pressures (3-3.5 MPa). Adsorbed natural gas (ANG) storage system provides reduction in compressor cost, tank manufacture cost and gas refueling cost (energy consumption of ANG is lower than that of compressed (CNG) and liquefied natural gas (LNG) storage systems) and improves environmental safety by transferring vehicles from gasoline to natural gas. This paper presents simulation results of charging of ANG vessel under the dynamic conditions where the heat effect is controlled by the fin and tube type heat exchanger.
Numerical Analysis of Experimental Turbulent Forced Convection Heat Transfer for Nanofluid Flow in a Tube
Authors: Sharma Korada Viswanatha , Azmi Wan Hamzah , Kamal Subhash , Hassan Suhaimi
Published: January 2016

A numerical model for determining the characteristics of flow and heat has been presented by modifying the eddy diffusivity equation of Sarma et al. The experimental data of thermo-physical properties determined using spherical particles in a wide range of concentration, particle size, materials and operating temperatures are available in the literature. The numerical analysis employed equations, which were developed using the experimental data of thermo-physical properties, friction factor and Nusselt number. Based on the agreement of the numerical results with the experimental data, the influence of concentration and temperature on the turbulent characteristics is presented. It is observed that SiO2 nanofluid attained higher velocity and lower eddy diffusivity compared to Cu nanofluid at a concentration. The temperature gradient increases with concentration and decreases with temperature.
Investigation on Potential Working Fluids for Waste Heat Recovery Applications
Authors: Struzyna Ralf , Menne Andreas , Steinmill Jens
Published: January 2016

Since topics like the greenhouse effect and the associated global warming issue are much more discussed in the past, automobile manufacturers have to become even more active in in two fields: reduction of fuel consumption and reduction of emissions. As the optimization of motor vehicles has reached a point at which significant additional fuel saving cannot be achieved by means of purely engine-internal measures alone, other systems must be found to improve the specific fuel consumption. One promising technology could be the use of engine waste heat contained in exhaust gas. Earlier studies have shown, besides systems like thermoelectric generators or a Turbo compounding system, an integrated Rankine Cycle offers a lot of potential to turn waste heat into mechanical or electrical power. The use of a suitable working fluid for this Rankine Cycle is required to achieve a maximum in system power output. The aim of this work is to investigate the suitability of working fluids for automotive Organic Rankine Cycle applications. The investigation is focused on the thermodynamic simulation on the one hand and the experimental evaluation of thermal stability of the fluids on the other hand. For the experimental evaluation of the stability a continuous cycle is used to achieve nearly equal process conditions. The stability tests start with a short time screening of all selected fluids, later on the most promising ones are tested in long time test runs. In the test runs, the substances of the categories alkanes, cycloalkanes, monoaromatics and fluorinated compounds show best results regarding stability. In contrast acetales, siloxanes and ethers are not stable under the selected conditions. The same applies to ethanol. With a temperature above 225 °C ethanol is not stable. Additional runs with ethanol show that the temperature has to be limited to below 250 °C at least to avoid a high decomposition. Also acetone reacting products can be found in the liquid phase leading to high boiling substances that then may lead to coke formation in the system. The validation of the tested and simulated fluids is done for two different condensation temperatures (CT) of 100°C and 40°C. Fluids acetone and ethanol (CT 100°C) show best overall results. In Addition fluids n-hexane, methylcyclohexane, cyclohexane and toluene show good upto very good results. For condensation temperature 40°C, cyclopentane and R1233zd is suggested.
Performance of the Solar Collector with Vacuum Tubes and Dual Heat Pipes Based on Wick Length Variation
Authors: Putra Nandy , Haliansyah Kristofer , Septiadi Wayan Nata
Published: January 2016

The increasing number of non-renewable energy and the rising need of energy caused some global issue. We always interested to discuss how human being could create and improve an instrument that can extract energy from renewable energy resources, which is clean and applicable. One instrument that can extract energy from the sun is solar water heater. Solar water heater, consist of two main components. The first one is storage tank, and the other is solar collector. The purpose of this research is to design, manufacture, determine the performance of the solar collector with vacuum tubes and dual heat pipe based on the wick length variation. This experiment used a 150 Watt halogen lamp as the simulator of the sun. A copper fin was utilized to collect heat from the sun and transfer the heat to heat pipes. Adiabatic walls made from Styrofoam and plywood were set to prevent heat transfer to the environment due temperature difference. The performance of the heat pipe was investigated based on the wick length inside the heat pipe. The flow characteristic inside of the heat pipe and the thermal resistance depend on the wick length. The study found that the full-length wick heat pipe has the best performance with 0.37 K/W thermal resistance, and the efficiency of the system reach 34.95%. This is the highest value compared to the half-length and three-quarter length wick heat pipe.
Multi-Layer Micro Channels System: Interpretation and Developments
Authors: Zaidan Husain , Mohd Ghazali Normah , Ahmad Robiah
Published: January 2016

During the last three decades the concept of the traditional cooling systems was modified to include single, double, and multi-layer micro channels. The new studies, applications, fabrication, and research focus on four main areas: the geometrical shape of the micro channels, the number of stacked layers, the type of the coolants, and the heat performance optimization. The previous studies have shown a significant reduction in the power consumption as the optimization is accomplished. In this paper, a semi-review for the previous works is provided, an attempt to interpret the nature of the work done, and show another trial for optimization. In this study, water was used as coolant, stacked multi-channel was adopted, and thermal resistance network was calculated. The heat sink under consideration is a rectangle of width W and length L. The thickness Hsub of the base of the micro-channel is 100 [μ m] while the depth Hc of the micro-channel is 500[μ m], both kept constant for all future optimization cases.
Energy Analysis of Split Air Conditioning System Using Variable Speed Drive
Authors: Mohd Nasib Affandi , Nasution Henry , Aziz Azhar Abdul , Oktaviandri Muchamad , Sumeru K. , Shodiya Sulaimon
Published: January 2016

An air conditioning (AC) system design requires two main aspects that should be taken into consideration, there are reducing energy consumption and ensuring thermal comfort. This paper present variable speed drive on compressor motor is being tested to reduce the energy consumption. Conventional AC system to use on/off controller where the compressor motor turns itself on and runs at maximum speed then turns back off to achieve the temperature setting. This controller consumes more energy, however, by using a variable speed drive, the compressor motor will constantly run at various speeds while achieving the temperature setting. A system that developed software to implement the controller algorithms was installed in a thermal environmental room with data acquisition to monitor the room temperature, energy consumption, energy saving and coefficient of performance. Measurements were taken during the one hour experimental period at a time interval of three minutes for temperature set-points of 22, 23 and 24°C with internal heat loads of 500, 700 and 1000 W. The proposed technique can save energy and thermal comfort in comparison with conventional on/off control. The experiment results indicate that the application of variable speed drive on compressor motor is better than conventional on/off.
Performance of Automotive Air-Conditioning System by Using Ejector as an Expansion Device
Authors: Mat Jusoh Firdaus , Nasution Henry , Aziz Azhar Abdul , Sumeru K. , Dahlan Afiq Aiman , Mohd Jamil Hishammudin , Fitri Khamis Mohamad
Published: January 2016

An automotive air conditioning system that uses thermal expansion valve (TEV) as an expansion device. The pressure drop from the condenser and evaporator pressure is considered an isenthalpic process (constant enthalpy), where this process causes energy loss (entropy generation) in the expansion process. The ejector recovers energy losses, which was previously lost in the expansion valve, and an ejector can be used to generate isentropic condition in the expansion process. The use of an ejector as an expansion device in this study can reduce power consumption of the compressor and increase cooling capacity of the evaporator. The experiments were conducted with temperature set-points of the conditioned space of 21, 22 and 23°C with internal heat loads of 100, 200 and 400 W. Measurements were taken during the one hour experimental period at a time interval of five minutes. The experiment results indicate that the ejector system is better than TEV and save fuel.
The Effect of Ambient Temperature on the Performance of Automotive Air-Conditioning System
Authors: Mohd Yunus Hisamudin , Nasution Henry , Abdul Aziz Azhar , Sumeru K. , Dahlan Afiq Aiman
Published: January 2016

The automotive air conditioning is one of the important things to be discovered and analyses to maximize the coefficient of performance (COP). The effects of the global warming in a surrounding world give a big impact on performance of air conditioning system in the vehicle. The significant of these issues make the ambient temperature changing. The ambient temperature it’s different according to the type of the place. The different ambient temperature will effect on the performance of air conditioning system. This study will analysis the energy consumption, temperature distribution and COP at various ambient temperature (30, 35 and 40°C), internal heat load (0, 500,700 and 1000 W) and engine speed (1000, 1500 and 2000 rpm) using HFC-R134a as the refrigerant. Measurements were taken during the 30 minute experimental period for temperature set point which 21°C. The results showed that the performance of the automotive air conditioning system decreases when ambient temperature, internal heat load and compressor speed increased.
Validation of Thermal Modelling for the Back Surface Temperature of a Photovoltaic Module for Hot and Humid Climate
Authors: Rosli Mohamad Afzanizam Bin Mohd , Mat Sohif , Sopian Kamaruzzaman , Sharif Mohd Khairul Anuar , Sulaiman Mohd Yusof , Ilias Salleh Elias
Published: January 2016

Thermal modeling is one of the approaches used to assess the performance of photovoltaic thermal. The main objective of this study is to validate thermal modeling by using the experimental results to estimate the back surface temperature of a photovoltaic module in hot and humid climate. Several assumptions have been made to simplify the analysis base on energy balance method. Good agreement is observed between the experiment and thermal modeling, with a correlation coefficient (r) and root mean square percent deviation of 0.931 and 12.1% respectively.
A Review on Butanol and Ethanol Fuels in Internal Combustion Engines
Authors: Hamid Abdullah Mustafa , Abdul Latiff Zulkarnain , Aziz Azhar Abdul , Mohd Perang Mohd Rozi
Published: January 2016

A controversial argument about alternative fuels is taking lots of researchers and scientists attention and so far ethanol and butanol, regardless their blending percentage, are the most promising alcohols due to their potential properties and low production cost. Many studies have been conducted to justify the optimum fuel to be implemented. In this work, a review will be conducted on both butanol and ethanol in internal combustion engine as well as their contribution in combustion engine regarding combustion performance, pollutant emission, ignition timing and knocking. According to the previous literature, an attractive advantage for alcohol-gasoline blends is that they don’t require engine modification design and still reduce the pollutant emission effectively. The properties of these fuels seem to prove not only that we can run our engines with a reduction of pollutant gases but with the emission of greenhouse gasses. This work will provide a review on ethanol and butanol as an alternative fuels and their properties and behaviour in the engine will be described individually.
Hydrodynamic Resistance Reduction of Multi-Purpose Amphibious Vehicle due to Air Bubble Effect
Authors: Maimun Adi , Nakisa Mehdi , Ahmed Yasser M. , Behrouzi Fatemeh , Koh Koh K. , Priyanto Agoes
Published: January 2016

Multipurpose Amphibious Vehicles (MAV) and other blunt shaped floating vehicles encounter the problem of a large bow wave forming and hydrodynamic resistance at high speeds. This wave formation is accompanied by higher resistance and at a critical speed results in bow submerging or swamping. Three new shapes of hull bow design for the multipurpose amphibious vehicle were conducted at several speeds to investigate the hydrodynamic phenomena using Computational Fluid Dynamics (CFD, RANS code), which is applied by Ansys-CFX14.0 and Maxsurf. The vehicle’s hydrodynamic bow shapes were able to break up induced waves and avoid swamping. Comparative results with the vehicle fitted with U-shape, V-shape and Flat-shape of hull bow, showed that the U-shape of the hull bow has reduced the total resistance to 20.3% and 13.6% compared with the V-shape and flat shape respectively. Though, the U-shape of hull bow is capable to increase the amphibious operating life and speed of vehicle. Also it has ability to reduce the vehicle’s required power, fossil fuel consumption and wetted hull surface.
On the other hand, the use of air cushions to support marine vehicles, heavy floating structures and in other operation is well known. The main problem in Multi-purpose Amphibious Vehicles (MAV) is the amount of power needed in order to overcome the hydrodynamic resistance acting on the hull which is included the frictional and pressure resistances. Therefore, more power is needed to move the MAV forward. In this respect, more fuel will be required to operate the amphibious vehicles. This problem could be effectively reduced by the introduction of the air cushion concept. With the air being drawn from top of craft to the cavity below the hull will produce some cushioning effect and also help to reduce skin friction drag. In this paper, air cushion effect will be studied in rigid surface cavity instead of using flexible skirts. This would avoid the problem of high maintenance due to replacement of damaged skirts.
Finally, the MAV will be supported using air cavity and bubbles generated by an air pump (compressor and air pressure vessel) to pushes the hull of multi-purpose amphibious vehicle up and reduce the frictional resistance due to draft and wetted surface reduction and layer of air between hull surface and water. This research would be done via CFD (ANSYS-CFX 14.0) and analyzed the hydrodynamic resistance
An Analytical Convergence Study of the Forced Air Cooling in Electronic Packaging
Authors: Ong K.A. , Abdullah Mohd Zulkifly
Published: January 2016

A forced air thermal cooling model has been developed by using Ansys software, to study at each step of the input power, what will be the corresponding junction temperature Few approaches were used to ensure the accuracy of the thermal simulation method, ranging from the minimum number of simulation iterations required in the finite element analysis, to the residuals target in terms of the momentum, continuity and energy equations, the objective is to ensure the simulations are converged and provide the reasonable results, which is also an indication of how the partial equations have successfully been solved with analytic method. The thermal resistance network in the model has also been established, mainly to understand the next level details in this thermal model by analyzing the correlation between the air flow and the thermal resistance at each junction, and also to understand the effect of the air flow with respect to the total thermal resistance. The thermal analytic model that built has proven to be healthy and it requires 200 iterations to achieve steady state with the reasonable temperature output, and there is no convergence issue in which the continuity, momentum and energy graphs showed the healthy trend, it achieved 10-7 for continuity, energy and momentum equations. it shows that when the air flow reduces the overall thermal resistance increases, in other word, reducing the air flow will increase the thermal resistance
Comparison of Different Neural Network Training Algorithms for Wind Velocity Forecasting
Authors: Assadi Morteza Khalaji , Safaei Shervin
Published: January 2016

In this paper the wind speed is predicted by the use of data provided from the Mehrabad meteorological station located in Tehran, Iran, Collected between 2003 and 2008. A comprehensive analogy study is presented on Comparison of various Back Propagation neural networks methods in wind velocity forecasting. Four types of activation functions, namely, BFGS quasi-Newton, Bayesian regularized, Levenberg-Marquardt, and conjugate gradient algorithm, werestudied. The data was investigated by correlation coefficient and characterizing the amount of dependency between the wind speed and other input data. The meteorological parameters (pressure, direction, temperature and humidity) were used as input data, while the wind velocity is used as the output of the network.The results demonstrate that for the similar wind dataset, Bayesian Regularized algorithm can accurately predict compared with other method. In addition, choosing the type of activation function is dependent on the amount of input data, which should be acceptably large.
Fabrication of UV-Curing Polyurethane Methacrylate (PUMA) Microchannel and Fluidics Interconnect for Microfluidics Applications
Authors: Abidin Ummikalsom , Burhanuddin Yeop Majlis , Yunas Jumril
Published: January 2016

Microfluidics platform offers a great advantage in bio-sensing and clinical diagnostics miniaturization. The requirement of inexpensive and rapid-prototyping materials are essential in microfluidics device commercialization. This paper presents rapid prototyping of UV-curing Polyurethane Methacrylate (PUMA) microchannel from the Polydimethlsiloxane (PDMS) mold. Two techniques in PUMA microchannel UV-curing rapid prototyping have successfully demonstrated in this work. The first technique utilized thin film transparency sheet as PUMA resin top surface cover in facilitating PUMA UV-curing. The second method exploited confined nitrogen gas environment in Pyrex dish chamber in expediting PUMA curing under UV light exposure. In this work, two different approaches of fluidic interconnect tubings for PUMA microchannel inlet and outlet are also presented. Reversible bonding techniques using corona discharge treatment are utilized for bonding of PUMA microchannel and fluidic interconnect with PUMA, silicon, glass and PDMS substrate. Accomplishment of preliminary fluid flow testing using PUMA microchannel proved its capability for microfluidics applications.
Analysis of an Airfoil Using a Transition and Turbulence Model
Authors: Islam Mazharul , Fürst Jiří , Wood David , Ani Farid Nasir
Published: January 2016

In order to evaluate the performance of airfoils with computational fluid dynamics (CFD) tools, modelling of transitional region in the boundary layer is very critical. Currently, there are several classes of transition-based turbulence model which are based on different methods. Among these, the k-kL- ω, which is a three equation turbulence model, is one of the prominent ones which is based on the concept of laminar kinetic energy. This model is phenomenological and has several advantageous features. Over the years, different researchers have attempted to modify the original version which was proposed by Walter and Cokljat in 2008 to enrich the modelling capability. In this article, a modified form of k-kL-ω transitional turbulence model has been used with the help of OpenFOAM for an investigative CFD analysis of a NACA 4-digit airfoil at range of angles of attack.
Effects of Non-Newtonian Viscosity on the Hemodynamics of Cerebral Aneurysms
Authors: el Gibaly Ahmed , El-Bassiouny Omar A. , Diaa Omar , Shehata Ali I. , Hassan Tamer , Saqr Khalid M.
Published: January 2016

The purpose of this study is to present a comparative study between Newtonian and non-Newtonian blood viscosity models for simulating the hemodynamic wall shear stress (WSS) of cerebral aneurysms. The non-Newtonian blood viscosity was modeled using the Carreau-Yasuda nonlinear model. Two realistic cerebral aneurysm models, derived from 3D angiography imaging, were studied and simulated via computational fluid dynamics solver based on finite volume method, with a pulsating sinusoidal waveform boundary conditions. The maximum wall shear stresses were found at the aneurysm’s neck and apex, the inlet arteriole recorded an average wall shear stress and as for the blebs and tips the wall shear stress values were remarkably low. The comparison indicated that non-Newtonian blood viscosity model predicted a lower range of WSS than of the Newtonian model, which provides more accuracy for simulating aneurysm hemodynamics.
Characteristics of Two-Phase Flow Pressure Drop of Propane in Horizontal Circular Small Tube
Authors: Pamitran Agus Sunjarianto , Novianto Sentot , Simanjuntak T.A. , Nasruddin Nasruddin , Alhamid Muhammad Idrus
Published: January 2016

This study experimentally investigated two-phase flow pressure drop of propane as refrigerant in horizontal small tube. Inner diameter and length of the tube were 7.6 mm and 1.07 m, respectively. In order to get pressure drop data, the experiment was conducted in various conditions of 10 to 25 kW m-2 heat flux, 200 to 628 kg m-2 s-1 mass flux, and 4.0 to 11.7°C saturation temperature. This study clearly showed the effect of heat flux, mass flux, and saturation temperature on the pressure drop of propane. This study also investigated which fluid properties gave higher effect on the frictional pressure drop due to its change over the process based on the recent experiment data. The existing pressure drop correlations were evaluated against the experimental result.
Evaluation of Relative Permeability Models in CO2/Brine System Using Mixed and Hybrid Finite Element Method
Authors: Pau J.S. , Pao William K.S. , Yong Suet Peng , Memon Paras Qadir
Published: January 2016

The requirement to reduce 40% carbon emission in 2020 has lead Malaysia to adopt the carbon capture and storage (CCS) technology in 2009. In this research, the pressure and transport differential equation for CO2 – brine phases flow is discretized using mixed and hybrid finite element method (MHFEM) which ensures the local continuity of the finite elements. Result shows that CO2 flow radially outward from the injection well. Three relative permeability models are investigated and it was find out that the simplified relative permeability model (SRM) has reduced the computational time by 8.3 times (when compare to Brooks and Corey model) but it is accurate for 1 year preliminary prediction. For longer period of prediction, classical Brooks and Corey and van Genuchten models shall be used.
Exhaust Energy Recovery with Turbo Compounding in a Heavily Downsized Engine
Authors: Mohd Noor Alias , Che Puteh Rosnizam , Abbas Muhammad Rabiu , Rajoo Srithar , Md Sah Muhammad Hanafi
Published: January 2016

Large amount of heat energy is wasted in Internal Combustion (IC) engine through the exhaust manifold, coolant, convective and radiative heat transfer. Significant amount of thermal energy waste occurring at the exhaust manifold of the IC engine can be recovered using various contemporary heat recovering techniques. The paper presented the viability of using turbo compounding waste heat recovering technique in recovering a significant amount of waste energy occurring at the exhaust of a heavily downsized engine. Electric turbo compounding (ETC) simulation using Ford Eco-Boost base line engine with modification using Hy-Boost modelled with AVL Boost software was carried out for the analysis. The simulation results show a 3% reduction in Brake Specific Fuel Consumption (BSFC), 0.5 bar Brake Mean Effective Pressure (BMEP) increase and up to 2 kW of power output were realized at engine speed of 2500 rpm. The result clearly indicates the effectiveness, viability and commercialization potentials of this waste heat recovery technique.
The Use of Tertiary-Butyl-Hydroquinone (TBHQ) in Minimizing Oxidation Effects on Palm Oil Based Lubricant Using Four Ball Tribotester
Authors: Syahrullail Samion , Zulhanafi Paiman
Published: January 2016

The extended uses of mineral oil based lubricant have continuously troubling the global environment issues. The remaining mineral oil resources also being the most debated issues in renewable energy conferences. Vegetable oils are still offering the highest possibility in replacing the mineral oil resources. This research is concerning on how to eliminate one of the disabilities found in palm oil based lubricant which is oxidation. Palm oil possessed unsaturated double bond in which susceptible to oxidation process. The simplest approach is to blend the palm oil based with anti – oxidant agent homogenously. This research was conducted using double fractionated palm oil (SPL) as lubricant and Tertiary-Butyl-Hydroquinone (TBHQ) as anti – oxidant agent to determine the tribology behavior including the coefficient of friction, wear scar diameter and the surface roughness profile. The experiment was also conducted using four-ball tribotester by following ASTM D4172B standard. Superior Mineral Engine Oil (EO) was used as comparison. The results found that SPL+TBHQ was able to reduce the coefficient of friction and provided lower surface roughness value. However it was unable to minimize the mean wear scar diameter compared to EO. The physical appearances of wear worn are also being observed in this research.
The Effect of Pits on the Curvature Cup: For Reducing Friction in Soft on Hard Sliding Contact
Authors: Syahrullail Samion , Daud Md Razak , Sapawe Norzahir , Yahya Azli
Published: January 2016

The purpose of this feasibility study is to elucidate the effect of surface modification on the curvature cup made of Acrylonitrile Butadiene Styrene (ABS) against metal ball bearing was investigated. In the tribology soft on hard (SoH), the pits embedded on the curvature cup have shown potential for reducing friction in curvature structure. A modified four ball machine as a hard-on-soft screening machine has been used to evaluate the friction on the curvature cup sample with an inner diameter of 12.8 mm. This study revealed that the treated curvature cup with pit in lubricated of palm oil optimizes the rate of frictional and allows for a stable of soft on hard sliding contact.
The Tribological Characteristics of RBD Palm Olein with Jatropha Oil Blend Using Four-Ball Tribotester with Different Normal Loads
Authors: Hassan Mohammed , Ani Farid Nasir , Syahrullail Samion
Published: January 2016

Vegetable oils are bio-fluids that could replace petroleum-based products due to its environment friendly characteristics and becoming an important source of bio-lubricants. The great advantage of vegetable oils is that they are widely available, renewable source of bio-lubricants. Moreover, vegetable oil based lubricant have shown the potential to reduce carbon dioxide and hydrocarbon emissions when operated in engines. There are two ways to use vegetable oil as a bio-lubricant, either use directly the neat vegetable oil without any additives or use with certain blending ratio of the vegetable oil with mineral lubricant. In this paper, the influences of the normal load on the tribological characteristics for the blending of two types of vegetable oils were investigated and compared with commercial lubricant oil by the use of the four ball tribotester. The vegetable blends are RBD palm olein and Jatropha oil ratio of RBD40/J60. All experimental works were conforming to ASTM D4172. The results exhibited that the both blending of RBD palm olein and Jatropha oil has lower the wear scar of ball bearings and coefficient of friction compared to commercial lubricant oil. As a conclusion, the blending of RBD palm olein and Jatropha oil has better performance compared to commercial lubricant oil or neat RBD palm olein.
Prediction and Analysis of Building Energy Efficiency Using Artificial Neural Network and Design of Experiments
Authors: Sholahudin Sholahudin , Alam Azimil Gani , Baek Chang In , Han Hwataik
Published: January 2016

Energy consumption of buildings is increasing steadily and occupying approximately 30-40% of total energy use. It is important to predict heating and cooling loads of a building in the initial stage of design to find out optimal solutions among various design options, as well as in the operating stage after the building has been completed for energy efficient operation. In this paper, an artificial neural network model has been developed to predict heating and cooling loads of a building based on simulation data for building energy performance. The input variables include relative compactness, surface area, wall area, roof area, overall height, orientation, glazing area, and glazing area distribution of a building, and the output variables include heating load (HL) and cooling load (CL) of the building. The simulation data used for training are the data published in the literature for various 768 residential buildings. ANNs have a merit in estimating output values for given input values satisfactorily, but it has a limitation in acquiring the effects of input variables individually. In order to analyze the effects of the variables, we used a method for design of experiment and conducted ANOVA analysis. The sensitivities of individual variables have been investigated and the most energy efficient solution has been estimated under given conditions. Discussions are included in the paper regarding the variables affecting heating load and cooling load significantly and the effects on heating and cooling loads of residential buildings.
Performance Enhancement of Tilt-Body Micro Air Vehicle by Use of Orthotropic Laminated Proprotors
Authors: Mohd Zawawi Fazila , Lv Peng , Prothin Sebastien , Morlier Joseph , Benard Emmanuel , Moschetta Jean Marc
Published: January 2016

A passive twist control is considered as an adaptive way to maximize the overall efficiency of a proprotor developed for convertible Micro Air Vehicles (MAV). In this paper, adaptation of the proprotor geometry in accordance to flight configurations is achieved by induced twist generated by the inherent structural coupling effect in anisotropic composite material and centrifugal force emanating from the tip load. Beam Finite Element Model based on Rotating Timoshenko Theory is used to predict structural loads, while Blade Element Momentum Theory is employed to predict the aerodynamic performance of adaptive proprotor as applied on Micro Air Vehicles (MAV). The iterative process of combination of aerodynamic model and structural model is used to compute the steady-state deformation of the flexible laminated proprotor blade due aerodynamic loads. Finally, the optimal design of lamina blade material is carried out to investigate the potential of flexible blade in the proprotorperformance enhancement.
Effectiveness of Jet Impingement Cooling System on Convex Surface
Authors: Musa Mohamad Nor , Fauzi Mohamad Faizal
Published: January 2016

Jet impingement is one of cooling method used in order to achieve high heat transfer coefficient and widely used in industry applications such as drying of textile and film, glass and plastic sheets, cooling of electronic equipment, and heat treatment of metals. In this research, it focused on the effectiveness of the jet impingement cooling system on the convex surface based on mass blowing rate and nozzle exit to surface parameters. The scope of experiment research encompasses are convex surface made of aluminum alloy and diameter 12.5cm. For mass blowing rate parameters, it use ʋjet = 1.98m/s, 3.03m/s, 4.97m/s and 6.00m/s which has Reynolds number range from 643 until 1946. Nozzle exit to surface distance,s/d = 4.0, 8.0 and 12.0. In this experiment model, a major components that involved are a compressor, nozzle, convex surface model, K thermocouple and heater. For the result of the experiment, it is based on the data obtain through a heat transfer coefficient and Nusselt number which the plotted graph focus on the space spacing and Reynolds number parameters. For the graph Nusselt number versus s/d at stagnation point c/d=0, it shown that when the Reynolds number increase, the Nusselt number also increase. In term of effectiveness, the s/d=12.0 has a good effectiveness jet impingement cooling system. For the graph of Nusselt number versus Reynolds at stagnation point, c/d=0, as Reynolds number increase, the Nusselt number increase too. From this experiment the better cooling effect is at Reynolds number, Re=1946. Thus, it can conclude that, effectiveness for jet impingement cooling system on the convex surface occurs at the highest Reynolds number.
Single-Objective Optimization of a Thermoacoustic Refrigerator
Authors: Zolpakar Nor Atikah , Mohd-Ghazali Normah , Ahmad Robiah
Published: January 2016

Optimization of energy-related systems with by-products that involve environmental degradation has never been so crucial today with depleting resources and global concerns over negative impacts on our environment. This paper reports the results of an optimization scheme on the coefficient of performance (COP) of a standing wave thermoacoustic refrigerator based on genetic algorithm. The environmentally friendly refrigerator operates without any CFCs, which has been associated with the depletion of ozone, a substance that prevents uv light from reaching the earth’s atmosphere. A single-objective optimization to maximize the COP of a thermoacoustic refrigerator has been completed. The variables investigated include the length of the stack, Lsn, center position of the stack, xsn, blockage ratio, B and drive ratio, DR. The results show that a COP of up to 1.64 is achievable which provides promise for future improvements in the present systems.
An Experimental Investigation of Condensation Heat Transfer Coefficient of R-410A in Horizontal Circular Tubes
Authors: Quang Vu Pham , Ba Chien Nguyen , Jong Taek Oh
Published: January 2016

Condensation heat transfer has been evaluated experimentally on the tube side of three different circular tubes with inner diameter of 6.2, 7.5 and 9.2mm, respectively. Two-phase fluid flow conditions include mass fluxes from 200 to 320kg/m2s, qualities between 0.1 to 0.9, and heat flus range of 5 to 20kW/m2 at a fixed saturation temperature of 48°C. Results showed that the average heat transfer coefficient increased with the increase of vapor quality, mass flux and heat flux, but decreased with inner diameter. The experiment results are compared with the existing heat transfer coefficient correlations, and a new correlation is developed with good prediction.
GNPs Reinforced Epoxy Nanocomposites Used as Thermal Interface Materials
Authors: Jiménez-Suárez Alberto , Moriche R. , Prolongo S.G. , Sánchez M. , Ureña A.
Published: January 2016

The current tendency in electronics is the reduction of size while continuously increasing the power consumption due to new functionalities and applications. Both aspects generate a heat increment. Consequently, dissipating the heat to the environment is necessary in order to avoid component overheating. [1,2]. The most efficient way to achieve it is to allow the heat to flow from the hot component to a heat sink. In order to improve the efficiency of this process, thermal resistance between both components must be reduced which is usually done by using a thermal interface material (TIM) between both surfaces [3-5]. This material should fill the gaps created due to the microscopic roughness of both surfaces and it must have good thermal conductivity [6]. These air filled gaps result in a very high contact resistance between joined parts, as the air thermal conductivity is very low [7].
Synthesis and Characterization of Yttrium Iron Garnet (YIG) Nanoparticles Activated by Electromagnetic Wave in Enhanced Oil Recovery
Authors: Soleimani Hassan , Latiff Noor Rasyada Ahmad , Yahya Noorhana , Sabet Maziyar , Khodapanah Leila , Kozlowski Gregory , Chuan Lee Kean , Guan Beh Hoe
Published: January 2016

Due to the geographical location and technological limitation, various novel enhanced oil recovery (EOR) methods has been proposed to recover the remaining oil from a depleted oil reservoir. Research on application of nanoparticles either on its own or coupled with other stimulating agents has been growing enormously and some of them have shown a promising future. In high temperature and high pressure reservoirs, thermal degradation will cause failure to the conventional chemicals. In this work, temperature-stable YIG magnetic nanoparticles with an electromagnetic wave has been proposed as a new candidate for reservoir stimulating agent. The purpose of nanoparticle injection is to increase the sweep efficiency in the reservoir by increasing the viscosity of displacing fluid. In this research, Yttrium iron garnet (YIG) nanoparticles have been injected into a waterflooded oil saturated porous medium to recover the remaining oil in the presence of an electromagnetic wave. At the sintering temperature 1200°C, a mixture of hematite and YIG was obtained, suggesting a higher temperature for single phase YIG. From VSM analysis, the average magnetic saturation, coercivity and remanence are 18.17 emu/g, 21.73 Oe and 2.38 emu/g, respectively. 1.0 wt% of YIG nanofluid was prepared and subsequently injected into the pre-saturated porous medium in the presence of square electromagnetic wave of 13.6 MHz. As much as 43.64% of the remaining oil in place (ROIP) was recovered following the injection of 2 pore volume of YIG nanofluid.
Synthesis of Graphene Oxide from Alternative Sources
Authors: Sanchez Miguel , Terence Mauro Cesar , Guevara Carrió Juan Alfredo
Published: January 2016

Two-dimensional films of graphene oxide (GO) have been synthesized using various oxidation methods such as the conventional or modified Hummers method. The redox method for graphite has shown promise at producing GO films on a large scale. However, this method is a very exothermic process that liberates gases that are harmful to the environment and humans. This article addresses the characterization of graphene oxide from alternative sources of carbon and using the dry method. Comparative studies performed using Raman spectroscopy suggest that this method is both promising and more environmentally friendly.