bluuebunny/crossref_metadata_2025 huggingface dataset:
Optimized and Distributed Variant Logic for Model-Driven Applications
Authors: Davis Jon , Chang Elizabeth
Published: November 2014

The customization of Enterprise Information Systems (EIS) is expensive throughout its lifecycle, especially across an enterprise-wide distributed application environment. The authors' ongoing development of a temporal meta-data framework for EIS applications seeks to minimize these issues with the application model supporting the capability for end users to define their own supplemental or alternate application logic as what they term Variant Logic (VL). VL can be applied to any existing model object, defined by any authorized user, through modeling rather than coding, then executed by any user as an alternative to the original application logic. VL is also preserved during automated application updates and can also interoperate directly between similar model-based execution instances within a distributed execution environment, readily sharing the alternate logic segments. The authors also present an enhanced pre-processing architecture that optimizes the execution of Logic Variants to the same execution order of single path model logic.
Reasoning Qualitatively about Handheld Multimedia Framework Quality Attributes
Authors: Hein Daniel , Saiedian Hossein
Published: November 2014

Today's mobile handheld devices, such as smartphones and action cameras, are well equipped for a wide range of multimedia and context-aware tasks. Such tasks can leverage traditional services like streaming audio and video as well as newer services like sensor fusion. Ubiquitous network access, coupled with an increasingly sophisticated mixture of device-based hardware and software, is enabling context-aware applications at an unprecedented rate. The objective of this chapter is to discuss specific quality attributes with respect to device-side software architectures providing these multimedia and sensor capabilities. This chapter focuses specifically on device-side client architectures rather than network or server architectures. Specific domain requirements and quality attributes are first derived through a synthesis of current research and industry trends, and subsequently analyzed. The analysis reveals some qualitative results that seem unintuitive at first glance but that become more understandable when provided with rationale relative to the handheld domain context.
Human Capital and External Knowledge Acquisition in Nonprofit Organizations
Authors: Kong Eric
Published: October 2014

Human Capital (HC) is defined as the human knowledge and knowing capability that an organization possesses that provide a competitive edge to the organization in the market. Organizational members' tacit knowledge, abilities, and skills to sense and understand the needs of external stakeholders, and constantly interact appropriately with the stakeholders for the benefits of their organizations, can be seen as a unique set of HC. External knowledge can be acquired through HC for strategic advantage and renewal. A review of the literature and a series of semi-structured in-depth interviews with 15 nonprofit members from 7 Australian NPOs reveal that there is a strong link between HC and external knowledge acquisition. This chapter argues that a better understanding of the relationship between HC and external knowledge acquisition is necessary if knowledge management, organizational learning, and an intellectual capital-view of the firm are to be fully integrated.
Intellectual Capital Measurement and Reporting Models
Authors: Nazari Jamal A.
Published: October 2014

This chapter extends the earlier study of Bontis (2001) by critically reviewing the existing methods to measure and report intellectual capital. Bontis's (2001) study contributed significantly to the intellectual capital measurement and reporting literature. However, despite the growth in the field of IC and development and introduction of several new approaches to measure and report intellectual capital, no recent study has synthesized the IC measurement and reporting models. The objective of this chapter is to fill this gap in the literature by providing a critical review of 28 IC measurement models. To achieve this objective, the author partially adopts Sveiby's (2007) suggested classification scheme for categorizing the existing measurement models. The classification will enable the reader to uncover the common attributes of each model and to contrast the dissimilarities.
Drivers of Innovation
Authors: Baporikar Neeta
Published: October 2014

Innovation helps organizations to grow. Growth, though measured in turnover and profit, can also occur in knowledge, experience, efficiency, and quality. Innovation is the process of making changes to existing, and it can be radical or incremental, applied to products, processes, or services. It can happen at all levels, from management teams to departments to individual. Various factors encourage and drive an organization to innovate. Each of these drivers demands continuity and learning. These drivers create a sense of urgency to create new organizational goals and generate new ideas for meeting these goals. The term innovation is often associated with products, but can also occur in processes that make products, services, or deliver products and services, including intangibles. This chapter focuses on innovation in the organizational context, describes concepts underlying innovation, and tries to understand the core of the innovation process: What drives innovation in organizations?
Educating Aviators
Authors: Kille Tarryn , Bates Paul , Murray Patrick S.
Published: November 2014

This chapter provides a critical examination of the evolution of distance education in tertiary aviation programs. By reviewing the literature and studies associated with Professional Pilot training, the chapter explores the issues affecting the delivery of distance education in university Professional Pilot programs, including the global shortage of Professional Pilots, the nature of work as a Professional Pilot, the importance of simulation, and the integration of assessment. In an effort to address some of the challenges, this chapter also offers recommendations and solutions. The authors contend that tertiary aviation distance education programs need to be adjusted to consider the needs of the student and industry by: (1) implementing action-based learning, (2) considering pedagogy before technology, (3) encouraging interaction and collaboration, and (4) embedding formative assessment. The chapter aims to contribute to the body of literature aimed at enhancing the effective delivery of distance learning in aviation tertiary education.
Online Delivery of Introductory Economics Content in the United States
Authors: Scheiding Thomas
Published: November 2014

Introductory economics courses for undergraduates have increasingly been delivered online. This chapter documents not only the number of economics courses taught online and the types of institutions where they are offered, but it also highlights how the online environment changes how students learn and faculty members teach. As for how students perform in an online classroom and whether learning online is superior or inferior to learning face-to-face, the evidence is mixed. The overall finding with regard to student learning, however, is that there is no statistically significant difference in student learning in either the face-to-face or online environment. Finally, certain kinds of technology can enhance student learning in an online environment such as video lectures, blogs, and frequent homework assignments that guide students. This chapter concludes with a discussion of instructional design and how to make informed technology and assessment choices in the economics classroom that enhance student learning.
Performance Calculations within the Conceptual Design Process of Hand-Launched Aircraft
Authors: Nadji Mehdi , Banazadeh Afshin
Published: October 2014

Matching diagram is a key part of the conceptual design process to determine the wing area and the required power. However, it requires drag polar estimation and the assumption of maximum lift coefficient. In case of conventional manned aircraft, early estimation techniques are based on statistical data that are not suitable for hand-launched aircraft. In this study, it has been attempted to present the performance calculations and a proper conceptual design model by acquiring sound values for the aerodynamic coefficients in low Reynolds number, using statistical wetted area as well as a raw design of fuselage, wing and tails. The process is applied to a sample scenario and the results are evaluated.
The Application of Multiple Vibration Neutralizers for Vibration Control in Aircraft
Authors: Zaman Izzuddin , Mohamed Salleh Muhammad , Manshoor Bukhari , Khalid Amir , Araby Sherif
Published: October 2014

A current challenge for researchers is the design and implementation of an effective vibration control method that reduces vibration transmission from vehicle structures such as aircraft. This challenge has arisen due to the modern trend of utilizing lightweight thin panels in aircraft structural design, which have the potential to contribute towards significant vibration in the structures. In order to reduce structural vibration, one of the common approaches is considering vibration neutralizer system attached to the structure. In this study, a vibration neutralizer is developed in a small scale size. The effectiveness of attached vibration neutralizers on a thin plate are investigated through experimental study. Prior to the experiment, a finite element analysis of Solidworks® and analytical modelling of Matlab® are produced in order to determine the structural dynamic response of the thin plate such as the natural frequency and mode shapes. The preliminary results of finite element analysis demonstrate that the first four natural frequency of clamped plate are 48Hz, 121Hz, 194Hz and 242Hz, and these results are in agreement with the plate’s analytical equations. However, there are slight discrepancies in the experiment result due to noise and error occurred during the set up. In the later stage, the experimental works of thin plate are performed with attached vibration neutralizer. Result shows that the attachment of vibration neutralizer produces better outcome, which is about 41% vibration reduction. It is expected that by adding more vibration neutralizer to the structure, the vibration attenuation of thin plate can be significant.
NACA 4415 Wing Modification Using Tubercles - A Numerical Analysis
Authors: Aftab Syed Mohammed Aminuddin , Ahmad Kamarul Arifin
Published: October 2014

In this work, the characteristic design of the humpback whale flippers is incorporated and investigated on NACA 4415 airfoil at very low Mach number. The effect of Tubercle Leading Edge on NACA4415 airfoil has been studied. This novel study attempts to mimic the effect of tubercles on the airfoil wing to improve lift and delay stall. The results showed significant improvement in aerodynamic performance of TLE when compared to CW. TLE, in comparison to wing with vortex generators, performed better. An improvement in lift by about 13.6% was obtained contrary to only 6.3% increase in case of VG under same Reynolds number. In addition, it was also observed that incorporation of tubercles further delayed stall and continued to produce lift at high angle of attacks.
A Laser Obstacle Warning and Avoidance System for Unmanned Aircraft Sense-and-Avoid
Authors: Sabatini Roberto , Gardi Alessandro , Ramasamy Subramanian
Published: October 2014

This paper presents an overview of the research activities performed to develop a new scaled variant of the Laser Obstacle Avoidance and Monitoring (LOAM) system for small-to-medium size Unmanned Aircraft (UA) platforms. This LOAM variant (LOAM+) is proposed as one of the non-cooperative sensors employed in the UA Sense-and-Avoid (SAA) system. After a brief description of the LOAM system architecture, the mathematical models developed for obstacle avoidance and calculation of alternative flight path are presented. Additionally, a new formulation is adopted for defining the uncertainty volumes associated with the detected obstacles. Simulation case studies are carried out to evaluate the performances of the avoidance trajectory generation and optimisation algorithms, which demonstrate the ability of LOAM+to effectively detect and avoid fixed low-level obstacles in the intended path.
Kenaf Fibre: Its Potential and Review on Bending Fatigue of Hollow Shaft Composites
Authors: Nadia Kassim , Ishak Mohamad Ridzwan , Misri S.
Published: October 2014

The fast growing use of composite in many applications has been focused on sustainable and renewable reinforced composites. Natural fibres were introduced and increasingly used due to their availability and environmental issues. Kenaf is the most common natural fiber used as reinforcement in polymer matrix composites (PMC). Therefore, this study analyzes the bending fatigue for kenaf fiber hollow shaft composite. The wet filament winding technique was used to prepare the composite specimens for the bending fatigue test. Different orientation angles (45° and 90°) and reinforced with aluminum were studied.
An Experimental and Computational Fluid Dynamic Study of Axis-Symmetric Coanda Configuration for VTOL MAV Applications
Authors: Wessapakdee Baramee , Makarasut Pranchalee , Thipyopas Chinnapat
Published: October 2014

This project is designed to find out a proper shape for the Coanda effect and use them for helping a vertical takeoff vehicle to create additional lift. Experiment and numerical calculations were conducted. The model was set up by placing a propeller at 10 cm above the surface. Shape, height and model with a hold at the center were investigated by ANSYS Fluent. Propeller was simulated by applying actuator disk. First shape is a semi sphere with 50 cm diameter. Second, surface in invert parabolic shape with 50 cm diameter with varying height 15, 25 and 35 cm are considered. The last shape is similar to the second case with 15 and 35 cm height, but it is made hollow by varying the hold's diameter as 7, 11 and 15 cm. The total number of the entire cases is 10. The result shows that the best shape for the Coanda effect is a semi sphere shape but total lift of all models without a hole in the middle, in the first and the second cases, are negative and tend to decline when the height of the shape increases. For the third case, the shape with a height of 35 cm and 15 cm hold diameter has the least negative lift.
Metallographic Investigation on the Effect of Cryogenic Temperature on Steel Weldments
Authors: Mohideen S. Rasool , Ahmad Mujahid Ahmad Zaidi , Shohaimi Abdullah , Ravi S.
Published: October 2014

Materials are subjected to low temperatures either intentionally as in the case of cryogenic fuels or non-intentionally as in the case of aerospace environment and are observed to undergo changes in their properties. Microstructural changes are the premier indications of changes in the properties of materials. This paper investigates the effect of cryogenic temperature on the microstructure of low alloy steel weldments. The weldments were subjected to liquid nitrogen temperature of 77K and the microstructures were analyzed using optical microscope and transmission electron Microscope. A distinct change in the microstructure was observed which would reason out the changes in the mechanical properties of weldments.
Further Development of the Kinematic and Aerodynamic Modeling and Analysis of Flapping Wing Ornithopter from Basic Principles
Authors: Djojodihardjo Harijono , Abd Bari Muhammad Anas , Mohd Rafie Azmin Shakrine , Wiriadidjaja Surjatin
Published: October 2014

The basis of this work was to understand the generation of lift and thrust of a flapping bi-wing ornithopter, which is influenced by its geometrical, dynamic, kinematic and aerodynamic features by following a generic approach in order to identify and mimic the mechanisms. As further development of earlier work, three-dimensional rigid thin wing is considered in flapping and pitching motion using strip theory and two-dimensional unsteady aerodynamics for idealized wing in pitching and flapping oscillations with phase lag. Later, parametric study is carried out to attain a complete cycle’s lift and thrust physical characteristics for evaluating the plausibility of the aerodynamic model and for the synthesis of an ornithopter model with simplified mechanism. Further investigation is conducted to identify individual contribution of generic motion towards the flight forces. Results are assessed in comparison with existing theoretical and experimental results as appropriate.
Real-Time Scheduling Procedures Based on Autonomous Distributed Manufacturing System (ADiMS) Concept
Authors: Yatna Yuwana M. , Raharno Sri , Ruriardi Rifki
Published: October 2014

This paper deals with the implementation of Autonomous Distributed Manufacturing System (ADiMS) concept in real-time scheduling in order to solve scheduling problems. Basically production scheduling is an important thing and has significant role in manufacturing system. Generally unpredictable conditions such as machine breakdown, absenteeism, or material shortages, in manufacturing system are a problem. These conditions will make the production schedule could not be implemented as planned. However, these conditions are difficult to be avoided and almost always occur in manufacturing systems. A real-time scheduling based on ADiMS concept that provide flexibility, adaptability, and capable could be use to face this problem. In this paper, the problem is limited to real-time scheduling procedures. The result of the case study is every process has been scheduled real-time manually in certain order by the real-time scheduling procedures based on ADiMS. This is showed that ADiMS concept could be implemented in a real-time scheduling and provides flexibility, adaptability, and capable to solve the scheduling problems.
Two Dimensional Maintenance Contracts for a Fleet of Dump Trucks Used in Mining Industry
Authors: Husniah Hennie , Pasaribu Udjianna S. , Cakravastia Andi , Iskandar Bermawi P.
Published: October 2014

In this paper, we study two dimensional maintenance contracts for a fleet of dump trucks operated in a mining industry. The two-dimensional contract is charaterised by two parameters (i.e. age and usage limits) which define a region. Two different shapes of the contract region are studied, where one region favors the customer, and the other the service provider. The maintenance service contracts studied is the performance based contract which offers incentives to motivate a service provider (an agent) to increase the equipment’s performance beyond the target. This in turn gives benefit for both the owner of the trucks and the agent of service contract. The decision problem under study is that an agent offers several two dimensional service contract options and the owner of the trucks has to select the optimal option. We use a Nash game theory formulation in order to obtain a win-win solution – i.e. the optimal strategy (pricing structure) for the agent and the optimal option for the owner.
Experimental Analysis on Ultrasonic Assisted Turning (UAT) Based on Innovated Tool Holder in the Scope of Dry & Wet Machining
Authors: Ibrahim Mohd Rasidi , Rahim Erween Abdul , Ghazali Mohd Imran , Chai Min Hong , Goh Zai Onn
Published: October 2014

In the past 17st century, revolution of industrial had been started and transited to new manufacturing processes, going from hand production to machining process. In order to reduce the manufacturing cost and protect the environment, several techniques are used. While lubrication play a significance role in variable parameters, such as tool life, cutting temperature, surface finishing, chip formation and cutting force.In this paper, ultrasonic assisted turning (UAT) was introduced for the machining of Aluminium 6061-T6. In this technique, ultrasonic vibration which excess 20kHz is combine with conventional turning process to achieve combined advantages of both techniques in machining process. UAT control system is developed using function generator to generate required frequency and output voltage direct connected to piezo actuator. While piezoelectric actuator PPA10M is the main device used to convert electrical energy to vibration energy,where the vibration transmitted to the cutting tip and perform in mechanical energy to remove unwanted material and produce precise dimension of work material. The characteristic of this machining process in theoretically capable to reduce tool wear, cutting force and based on current experimental analysis had shown significance improvement on surface finishing and reduction in tool wear. In the present work, comparison data had been done based on conventional and advanced machining process in the scope of wet and dry machining on AL6061-T6.
Stress Distribution in Composite Double-Lap Bolted Joints Incorporating with Clamp-Up
Authors: Ahmad Hilton
Published: October 2014

A 3-D FEA has been carried out to determine the stress distribution in bolted double-lap bolted joints using ABAQUS CAE and compared with available closed-form equations. As friction load in bolted joint is transferred through-the-thickness, the 3-D finite element model gave more reliable stress distribution than simplistic 2-D closed form (incorporated with clamp-up). Similar trend in stress distribution were found for closed-form and FEA approaches.
Synthesis of Zeolite from Geothermal Waste
Authors: Sulardjaka Sulardjaka , Fitriyana Deni Fajar , Adi Agus Purnomo
Published: October 2014

The high content of silica in geothermal waste can be used as a alternative source of amorphous silica for the production of silicon based materials. In this research, geothermal waste was used as silica sources in hydrothermal reaction of zeolite synthesis. Zeolite was synthesized by unstirred hydrothermal process. Hydrothermal process was conducted at variation temperature 100, 110 and 120 °C for 5 hours. To study the effect of holding time on hydrothermal product, hydrothermal process also done in variation of: 1, 3 and 5 hours holding time at temperature 120 °C. All of hydrothermal products were characterized by XRD. The results show hydrothermal process successfully converts geothermal waste into zeolite A and sodalite.
Comparison between Nitrogen-Oil-Mist and Air-Oil-Mist Condition when Turning of Hardened Tool Stainless Steel
Authors: Handawi Mohamed , Elshwain Amad Elddein Issa , Noordin Mohd Yusof , Redzuan Norizah , Kurniawan Denni
Published: October 2014

Minimum quantity lubrication (MQL) or as it’s called semi dry cutting is a technique which spray a small value of lubricant flow rate to the cutting zone area. MQL has been used in many machining process with different cutting tools and workpiece materials due to its green environments and economically advantageous. MQL has become an attractive option to dry and flood cutting in terms of reduce the temperature in the cutting zone and reduce the cost of the product. However, in MQL seems to be machining limited by cutting temperature, because at high speed the effect of oil mist becomes evaporated. Therefore another alternative cooling approach was used with oil mist in this research. This research presents study the performance of nitrogen gas as a coolant and oil mist as lubricant in turning of hardened stainless tool steel (STAVAX ESR) with hardness 48 HRC. Using a gas as coolant with oil mist is a new solution for enhancing machinability. Turning experiments are carried out on CNC turning machine. The cutting insert grade is KC5010 (PVD-TiAlN wiper coated carbide). The experimental results were: 1) nitrogen gas with oil mist prolongs tool life compare with air with oil mist. 2) better product surface finish by using nitrogen gas with oil mist.
Fabrication of AA6061-0/RHA Surface Composite via Friction Stir Processing
Authors: Abdulmalik Samir Sani , Ahmad Rosli
Published: October 2014

Friction stir processing is a novel process evolved to fabricate surface metal matrix composites. Rice husk ash (RHA) is an agro-industrial waste and by product of rice husk. The feasibility of incorporating RHA powder into aluminium alloy AA6061-0 as reinforcement particles to make surface matrix composite via FSP is reported in this paper. The optical micrographs revealed a homogeneous distribution of RHA particles which were well bonded with the matrix in both first and fourth-passes of the FSP due to mechanical stirring. Microhardness of the stir zone SZ with the RHA particles of I-pass increased to about 106 HV, 40% higher than that of the base material 66 HV by dispersed RHA particles.
Iron Oxide Rust as Raw Material for the Production of Red Pigment in Paint Industry
Authors: Kiong Sia Chee , Hakimi Mohd S. , Ong Pauline , Fie Kuang Jie
Published: October 2014

In this study, the potential of rust as a pigment in paint technology via sintering process was investigated. Iron (III) nitrate was the raw material used to make rust or iron oxide. The characteristics of iron oxide were analyzed. Moreover, iron oxide was mixed with other chemical components to make paint. The properties of paint in both liquid state and solid state were determined by portable field viscometer, pH indicator, glossmeter, pencil hardness test, and tape adhesive test. The optimum ratio of paint components for this study where used iron oxide as pigment. The other properties of pigments and paints will be conducted in the analysis study.
Parameter Optimization of Debinding Injection Moulded Ti-6Al-4V Mix with Palm Stearin and Polyethylene
Authors: Jamaludin Mohd Ikhwan , Mohamad Nor Nor Hafiez , Abu Kasim Nur Atikah , Saedon J.B. , Muhamad Norhamidi
Published: October 2014

Debinding process of injection moulded Ti-6Al-4V feedstock was divided into two parts: solvent debinding process to eliminate palm stearin (PS) and thermal pyrolysis to eliminate polyethylene (PE). Solvent debinding process used heptane at optimum temperature, 60°C to remove PS binder completely as temperature is the only parameter that can be optimized. Thermal pyrolysis parameters for removal of PE binder from the injected 65vol% Ti-6Al-4V feedstock have been optimized by using Taguchi method. Heating rate, temperature and time were the selected factors during experiment to be applied in the L9(34) Taguchi orthogonal array (OA) to find the best set of parameters to produce highest density of brown part. Thermal pyrolysis process was done at optimum parameters: heating rate: 5°C/min; temperature: 510°C; and time: 90 minutes. Analysis of Variance (ANOVA) was employed to find the best signal to noise ratio (S/N) to express the contribution of the factors towards quality characteristic. Based on the results, heating rate has the greatest contribution (54.63%), followed by duration time of thermal pyrolysis (24.40%) and temperature (19.25%).
Effect of Cr to Fe on the Solid Solubility, Lattice Parameter and Strain of Fe80Cr20 Alloy Powder
Authors: Feriyanto Dafit , Idris Maizlinda Izwana , Sebayang Darwin
Published: October 2014

-Fe-Cr phase was investigated using formula Fe80Cr20. Ball milling process and ultrasonic technique is successfully done to develop solid solubility and improve homogenous, respectively. However, the effect of the Cr to Fe powder is not complete investigated using combination of its process. Ball milling is conducted by milling time of 60 hours and ultrasonic technique were carried out at ultrasonic time of 3 h, 3.5 h, 4 h, 4.5 h and 5 h. From the strain effect analysis is obtained that the strain increased with crystallite size decreased and broad peaks due to the micro strain that is obtained from the increasing d-spacing. The solid solubility and lattice parameter of the material relatively increased from the untreated sample to treated samples with the highest solid solubility of 62.1% and highest lattice parameter of 3.091 nm which is located at the milled and UB 4.5 hours. It is caused the temperature increased that effect to the higher diffusion of the atom. Therefore, the combination treatment is highest promote to improve the properties of the metallic materials.
The Effects of Storage Duration on Biodiesel Derived from Waste Cooking Oil
Authors: Azman Norazwan , Suardi Mirnah , Khalid Amir
Published: October 2014

The use of fossil fuels as energy sources has grown to significantly be likely to have a major environmental impact. Reduction of world oil reserves and increasing environmental concerns have prompted alternative is found and renewable source of energy called biodiesel. Biodiesel fuel from vegetable oil is considered as the best candidates for diesel fuel replacement in diesel engines because of its closer. Fuel prices are going up day by day in the world. Thus, the means and methods have been trying for years to get fuel alternative outcomes. This study investigated the effects of different storage periods used in quality biodiesel blends (B5, B10, B15) of waste cooking oil and diesel fuel under low temperature and the temperature of the environment. Biodiesel samples were stored in glass containers under indoor conditions, and outdoor conditions for 10 weeks in total. These samples were monitored on a weekly basis through the test properties. The experimental density, viscosity, acid value, water content and flash point discussed in detail. Biodiesel storage at low temperatures is suitable and more advantageous because the impact on the physical properties is minimal and beneficial to slow down the degradation of biodiesel and storage.
Simulation Analysis of the Effect of Temperature and Exchange Current Density on Power and Hydrogen Production of (PEM) Electrolyzer
Authors: Tijani Alhassan Salami , Haiyoon Mohd Ariffuddin
Published: October 2014

The purpose of this manuscript is to analyze the effect of temperature and exchange current density on operating cell voltage, resistance and ionic conductivity of the polymer electrolyte. Equations related to mathematical models for PEM Electrolyzer based on a combination of thermodynamics fundamental and electrochemical relations of the well-known Butler-Volmer kinetic have been used to simulate the system. The result of this study shows a significant drop in membrane Ohmic resistance as the temperature decreases. In conclusion the best operation temperature that corresponds to lower voltage (1.82 V) is 80°C. At power density of about 9 W/ cm2, hydrogen flow rate of 3.5ml/min and 3.78 was observed at 40°C and 80°C respectively, this account for only about 7% increase hydrogen flow rate. These model results are found to agree well with previous published work.
Low and High Purity Methanol Effect on Performance and Smoke Emission of Direct Injection Diesel Engine with Cooled EGR Fueled by Diesel Fuel and Jatropha Oil Blends
Authors: Syaiful Syaiful , Sobri Sobri , Tandian Nathanael P.
Published: October 2014

The aim of this study is to experimentally investigate an effect of low and high purity methanol on a performance and smoke emission of diesel engine with cooled EGR system fueled by diesel fuel and jatropha oil blend. A four-stroke water cooled direct injection (DI) diesel engine with cooled EGR system was used in this work. The diesel engine was fueled by diesel fuel, jatropha oil and low (LPM) or high (HPM) purity methanol blends at the ratio of 100/0/0, 75/20/5, 70/20/10 and 65/20/15 % on volume basis respectively for the variation of engine loads in the range of 25 to 100% with 25% increments at 2000 rpm. Each load for every fuel blend was given by the 0% and 16.5% EGR rates. The results are found that the brake power for diesel engine fueled by diesel fuel, jatropha oil and LPM is approximately 8% lower than that of diesel engine fueled with the neat diesel, while it increases to 5.24% at the low load and reduces to 6.11% at the high load by injecting HPM in the fuel blends. At the same case, BSFC increases approximately 4.5% by injecting LPM in the fuel blends. The brake thermal efficiency rises approximately by 3.3% with LPM in the fuel blends, whereas it increases approximately 6% by injecting HPM. The smoke opacity reduces approximately by 70% with LPM or HPM in the fuel blends.
Mass Fraction Burn Comparison of Compressed Natural Gas and Gasoline
Authors: Ramasamy Devarajan , Zainal Z.A , Bakar R.A. , Kadirgama K.
Published: October 2014

Vehicle efficiency relates to pollutants and cost savings in third world countries. In term of subcompact cars, the vehicle characteristics are governed by the engine for alternative fuels. The main focus of this paper was to evaluate a sub compact car engine for its performance and burn rate of gasoline and Compressed Natural Gas (CNG). A bi-fuel sequential system was used to do this evaluation. Measurements of engine speed, torque and fuel were done on an eddy current dynamometer, while measurements or in-cylinder pressure, crank angle and spark were analyzed from results taken by data acquisition system. The emissions readings were also compared from an emission analyzer. The results were analyzed for burn rate based on the first law of thermodynamic. The comparison shows a drop of 18.6% was seen for the power, brake specific fuel consumption (BSFC) loss was 7% and efficiency loss was at 17.3% in average for all engine speed. Pressure analysis shows peak pressure dropped by 16%. Burn rate shows why CNG had a slower burning speed on the small engine. The engine speed of 4000 rpm at Maximum Brake Torque (MBT) produced the most nearest results to gasoline.
One-Dimensional Simulation of the Combustion Process in an Engine Cylinder with Ethanol
Authors: Kathri Akasyah M. , Mamat Rizalman , Aziz Amir Bin , Alias Azri , Abdullah Nik Rosli
Published: October 2014

The diesel engine is one of the most important engines for road vehicles. The engine nowadays operates with different kinds of alternative fuels, such as natural gas and biofuel. The aim of this article is to study the combustion process that occurs in an engine cylinder of a diesel engine when using biofuel. The one-dimensional numerical analysis using GT-Power software is used to simulate the commercial four-cylinder diesel engine. The engine operated at high engine load and speed. The ethanol fuel used in the simulation is derived from the conventional ethanol fuel properties. The analysis of simulations includes the cylinder pressure, combustion temperature and rate of heat release. The simulation results show that in-cylinder pressure and temperature for ethanol is higher than for diesel at any engine speed. However, the mass fraction of ethanol burned is similar to that of diesel. MFB only affects the engine speed.
Evolutionary Algorithm Based Multi-Objective Aerodynamics Optimization Method for Low Reynolds Number Airfoil
Authors: Zuhal Lavi R. , Dwianto Yohanes Bimo , Palar Pramudita Satria
Published: October 2014

This paper presents the development of multi-objective population-based optimization method, called Non-dominated Sorting Genetic Algorithm II (NSGA-II), to optimize the aerodynamic characteristic of a low Reynolds number airfoil. The optimization is performed by changing the shape of the airfoil to obtain geometry with the best aerodynamic characteristics. The results of the study show that the developed optimization tool, coupled with modified PARSEC parameterization, has yielded optimum airfoils with better aerodynamic characteristics compared to original airfoil. Additionally, it is found that the developed method has better performance compared to similar methods found in literature.
Vibration Exposure Analysis of the Polysiloxane Reinforced with Rice Husk Silica
Authors: Mahzan Shahruddin , Azmi Mohd Azham , Taib Hariati , Mohammad Nurul Emi Nur Ain
Published: October 2014

One of approaches to protect devices from unpleasant vibrating disturbances is by employing a vibration absorber. This paper explores the viability of polysiloxane as raw material, added with rice husk silica fillers to produce a vibration absorbent sheet. The polysiloxane reinforced with rice husk sheets were made using hot compression moulding technique. The samples were tested for its density and tensile tests according to related standards. As for vibration test, a portable hand grinder was used to estimate the vibration exposure experienced by the users. The polysiloxane sheets were strapped on the tool’s handle and the vibration exposure was measured. The result shows that by applying the polysiloxane sheets on the tool grinder reduces the vibration magnitude by a maximum value of 38 percents. The longest vibration time exposure was recorded for 6.42 hours, improved by 150 percents from the original vibration time exposure of 2.52 hours. The results also demonstrated that polysiloxane with 4 wt. % rice husk silica was the optimum combination for vibration application since it produced highest vibration magnitude reduction and longest vibration exposure time of grinder applications.
Laser Assisted Micro-Groove Ball Milling of Ti6Al4V
Authors: Mohid Zazuli , Warap N.M. , Ibrahim R. , Rhim E.A.
Published: October 2014

In micro scale, the size of cutting tool and shape significantly contributed to the machining performance. Many studies have been done to improve the cutting tool life and machined surface quality. Problems could become more severe when the workpiece has a low thermal conductivity while having high level of ductility such as titanium alloy. In this study, micro ball mill cutting tool is selected to produce a linear groove on a titanium alloy plate. The process is integrated with a laser source as a pre-heating element on the work piece surface. The condition of the flank surface of the tools and cutting force were observed and discussed. The influence of tool orientation and laser heating parameters in laser assisted micro ball milling (LAMM) were also discussed. It was found out that adhesion is the dominant tool wear mechanism thus fluctuate the cutting force value.
Measurement of Mechanical Properties of St 37 Material at High Strain Rates Using a Split Hopkinson Pressure Bar
Authors: Afdhal Akbar , Gunawan Leonardo , Santosa Sigit P. , Putra Ichsan Setya , Huh Hoon
Published: October 2014

The dynamic mechanical properties of a material are important keys to investigate the impact characteristic of a structure such as a crash box. For some materials, the stress-strain relationships at high strain rate loadings are different than that at the static condition. These mechanical properties depend on the strain rate of the loadings, and hence an appropriate testing technique is required to measure them. To measure the mechanical properties of a material at high strain rates, ranging from 500 s-1 to 10000 s-1, a Split Hopkinson Pressure Bar is commonly used. In the measurements, strain pulses are generated in the bars system, and pulses being reflected and transmitted by a test specimen in the bar system are measured. The stress-strain curves as the material properties of the test specimen are obtained by processing the measured reflected and transmitted pulses. This paper presents the measurements of the mechanical properties of St 37 mild steel at several strain rates using a Split Hopkinson Pressure Bar. The stress-strain curves obtained in the measurement were curve fitted using the Power Law. The results show that the strength of St 37 material increases as the strain rate increases.
An Evaluation of Drag Coefficient of Wind Turbine System Installed on Moving Car
Authors: Sofian Mohd , Nurhayati Rosly , Rexca A.Jamit , Syariful S. Shamsudin , Aslam Abdullah
Published: October 2014

This study presents a simulation result of an evaluation of the aerodynamic performance of a moving car with a wind turbine system. Sedan type cars (approaching the size of Proton Wira car) were modeled using the SolidWork software and simulation was done by ANSYS FLUENT software. Three car models with different wind turbine system positions (in front of the front bumper, on top of the hood and on top of the roof) plus one model without the wind turbine system were simulated. The study proved that the position of the wind turbine system installation will change the characteristic of the air flow around the car body and affects the aerodynamic performance of the car. Extended front bumper of a car is not significantly affecting the aerodynamic performance of the car. This extended bumper seems to be the suitable area to install a wind turbine system and the investigation shows that the aerodynamic performance of the car improved due to lower drag coefficient, Cd..
Gravitational Effect Formulation on In-House Air-Particle Flow Solver
Authors: Ngali Mohd Zamani , Zakaria Nazri Huzaimi , Osman Kahar , Khalid Amir , Manshoor Bukhari , Zaman Izzuddin Bin
Published: October 2014

Conventional efforts on the design of air-particle related environments are merely on heuristic and experience basis. Distribution control of particles in air such as dust, soot, smoke, chemical aerosol or any other pollutants are only simulated in current years when computational power is slowly fading from being an issue. Most commercial engineering software already equipped with the features but in-house solvers are always developed by institutions of related fields in order to fulfil their research needs. This work is preformed specifically to analyse the effect of additional gravitational effect feature in our newly developed in-house fluid-particle software. The effect is included in the Eulerian-Lagrangian solver so that it capable of simulating heavy particles in environmental air flows. Flow distributions of heavy particles such as liquid aerosol, sand or granular fertilizer are greatly affected by gravitational effect as compared to relatively buoyant particles such as smoke and light dust. Transient particle distribution in a ventilated room is simulated in this work. 10,000 particles that represent homogenous 2 mm Hemlock wood dust were randomly distributed in 3.3x2.8x5.9 m3 ventilated room that consist of two ceiling air intake and four bottom wall ventilation outlets. Homogeneous Hemlock wood solid sphere particles with diameter of 2 mm is simulated while the air intake is equivalent to 0.0944 m3/s. Simulation without the particle gravitational effect shows physically irrational results where 26 % of particles stayed at the top half of the room. Simulation with particle gravitational effect shows otherwise where 92 % of the particles settled at the bottom half of the room when measures at the same transient duration. This finding agrees well with distribution patters of previous experiments and simulation works. The introduction of gravitational effect in the newly developed in-house air-particle solver can be considered as the turning point where simulations of environmental air-particle related studies such as dust ventilation, aerosol control or even granular fertilizer distributions out of boom sprayer are possible.
Effect of Baffle Openings to the Flow Distribution in a SERVCO Fume Cupboard
Authors: Omar Mohd Amal Asrol , Wisnoe Wirachman , Bakri Azman
Published: October 2014

Recirculation region behind a fume cupboard sash is the potential contributor to the leakage of the contaminants due to its large size. This is found from the computational fluid dynamics (CFD) simulation of SERVCO fume cupboard using κ-ω turbulence model. For a good fume cupboard, the recirculation zone needs to be minimized while maintaining the flow distribution to all area in the fume cupboard. The opening on the baffle may reduce the recirculation zone which in turn may reduce back flow that is the cause of leakage. In this paper, the effect of shape of baffle openings on flow distributions of a SERVCO fume cupboard will be presented as a result of CFD. The results are presented in terms of velocity vectors Vy (in the direction towards the sash opening) at different cross sections for 4 opening shapes. The opening is found to improve the airflow distribution.
Performance Analysis of Integrated Collector System with Immersed Coil Heat Exchanger
Authors: Afolabi Lukmon Owolabi , Al-Kayiem Hussain Hamoud , Aklilu Tesfamichael Baheta
Published: October 2014

The performance of integrated solar collector / thermal energy storage with immersed heat exchanger was investigated experimentally at the Solar Research Site, University Technology PETRONAS, (4.4224oN, 100.9904oE), Malaysia. The experimental set up consisted of 150 liters storage tank capacity with immersed coil heat exchanger, single glazing 1.5m2 flat plate collector with 15o tilt to the horizontal. The circulation of the working fluid was by forced in closed loop with a mini solar pump. Aluminum cell foam was attached to the absorber as extended surface. The surface of the collector was coated with black ornament to improve its absorption. The system was tested under clear skys, for two cases; with and without water drawn-off for seven days per case studied. The performance evaluation data obtained for case1 at the mean maximum solar intensity was 503.98 W/m2 were: maximum daily water temperature 63°C, average daily water temperature 46°C, collector efficiency 63% and system efficiency 43%. Whilst for case 2, the mean maximum solar intensity was 473.11 W/m2, the maximum daily water temperature 54°C, average daily water temperature 39.36°C, collector efficiency 54% and system efficiency 39%. The system efficiency for case 2 showed that the heat exchanger performed slighlty better and the water drawn-off effect is minimal.
Finite Element Analysis of Sheet Metal Formability Effect on Automotive Part
Authors: Mohd Ariffin Mohd Khairol Anuar , Sulaiman Sreenivasan , Mohd Ruslan M.S.
Published: October 2014

An increasing demand for lower price and better quality vehicle has increase complexity of tool development process. This includes concept evaluation, design phase, prototype phase and pre production phase. Experience show that R&D spends most of the time and cost for tool development process, which includes assembly tooling, product tooling for automobile sheet metal component or part requires the highest cost in tool development process as most metal stamping part requires more than one tool to produce finished stamping part. For these reason, sheet metal forming simulation and analysis at early stage of tool development process is very important to shorten the tool development cycle time and cost. In other word by applying sheet metal forming simulation and analysis at early stage it can reduce the die manufacturing cycle time and cost.
Assessment of Child Occupant Protection in ASEAN NCAP
Authors: Solah Mohd Syazwan , Md Isa Mohd Hafzi , Hamzah Azhar , Ariffin Aqbal Hafeez , Ahmad Yahya , Mohd Jawi Zulhaidi , Abu Kassim Khairil Anwar
Published: October 2014

Statistics show that child traffic injuries are a public health problem globally, including Southeast Asia (SEA) region. With an overall value of road traffic death rate among children of 7.4 per 100,000 populations has put SEA as the second region to have the highest death rate after Africa. Due to this alarming figure, many safety interventions and inventions have been introduced and implemented to mitigate child injuries resulted from road traffic accidents. One of them is the establishment of crashworthiness rating programme for new passenger cars to evaluate the resulted child injuries via destructive tests. The New Car Assessment Programme for Southeast Asia region (ASEAN NCAP) established to elevate vehicle safety standards, raise consumer awareness and encourage market for saver vehicles in the dedicated region. Currently the programme assessed and rated passenger cars based on performance of adult and child occupant protection in frontal offset crash tests. Since its introduction, ASEAN NCAP has crash tested 28 popular passenger cars throughout its development phases. During these phases, there has been improvement on the rating of child occupant protection (COP) with the increase of number of cars getting 4-star. This paper presents the results of ASEAN NCAP tests for the development phases in term of COP rating as well as provides explanation on the related assessment.