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Title: Writing Strategies of Malaysian ESL Undergraduate Engineering Learners
Author(s): Muhammad Ridhuan Tony Lim Abdullah, Zulqarnain Abu Bakar, Razol Mahari Ali, Raja Ahmad Iskandar Raja Yaacob, Abdur-Rahman M. A., Abd Mutalib Embong, Am Zairi bin Amar
Pages: 1-9 Paper ID: 110802-3939-IJET-IJENS Published: April, 2011
Abstract: One of the most significant factors that affect the performance of learners with learning a second language is difficulty with written skill. This paper reveals a study conducted as a qualitative research to analyze the written product as well as writing strategies of four ESL Malay undergraduate engineering students of a local private university used while completing a writing task. Specifically the study aimed to address the following research questions : 1) What are the writing strategies used by four ESL Malay undergraduate engineering students when they write composition in English? 2) Are there any differences between the writing strategies used by good ESL students to those used by the weaker ones? Think-aloud protocols, written essays, post-session interviews and audiotapes were used to examine the writing processes and strategies of two groups of students, two students in each group of good and weak learners. The think-aloud and interview protocols were transcribed verbatim for analysis. Analyses of the findings revealed that the two groups of students shared common writing strategies mainly cognitive strategies to generate ideas for their essay. Metacognitive and Social strategies were also used to aid in generating of ideas and searching for correct words or expressions. The strategies were used in combination and in a recursive manner to attain certain goals in their writing. The difference in the strategy use between the two groups of good and weak students lies in the amount of strategies being used, reason for the use and how the students regulated the strategies to solve problems concerning the writing task.
Keywords: Writing strategies, cognitive, metacognitive, social, skilled learners, unskilled learners.
Full Text (.pdf)  International Journals Of Engineering and Science| 506 KB
Title: A Proposed Route Selection Technique in DSR Routing Protocol for MANET
Author(s): Mamoun Hussein Mamoun
Pages: 10-13 Paper ID: 118702-0404-IJET-IJENS Published: April, 2011
Abstract: This paper presents a novel technique for optimizing the efficiency of route discovery. The optimization aims to minimize the number of cached route request (RREQ), which is a significant source of overhead for the dynamic source routing (DSR) protocol. Our proposed technique is based on a decision algorithm that weighs individual links as a path to the necessary destination is being constructed if this link is deemed suitable by the fuzzy logic system it is added to the path and route construction continue. The fuzzy controller is used to instruct route construction continue as only good quality links are recorded in source destination paths. A productive decision using a fuzzy logic system is applied to the route discovery technique to curb non-optimal network floods. This action causes a cessation in the generation of low quality routes as only paths with good routing metrics are selected for the rebroadcast of route discovery packets. Consequently, route query packets arriving at the necessary destination node, or at some intermediate node with knowledge of the destination node, generate high quality route replies Performance results show that the propagated route request overhead can be reduced by more than 30% under high node mobility. Also, our proposed algorithm can significantly reduce the average end-to-end delay. Furthermore Simulation results show that the packet delivery ratio increases when proposed algorithm is used in comparison with the standard DSR routing protocol.
Keywords: MANET, New routing protocol for MANET, DSR.
Full Text (.pdf)  International Journals Of Engineering and Science| 360 KB
Title: A Multi-Channel Clustered Web Application Server: Architecture
Author(s): Kareim M. Sobhe, Ahmed Sameh
Pages: 14-25 Paper ID: 111902-8484-IJET-IJENS Published: April, 2011
Abstract: Web applications’ environments do provide open standards and well published interfaces that allow easy deployment, expandability, integrity, and mission critical servicing. As much work has been done on the standardization of interfaces, and inventing new development models to serve such standardization as well as on other important features like expandability, extendibility, high availability, and business logic isolation, performance has always come later in priority. Performance was always left to be handled by the advances made in the field of hardware, either in processing components like semiconductors, or in communication hardware protocols. Few moves have been taken in the direction of performance from software perspective. Most web application environments have been built on top of the current standard backbone architecture of web environments. In this paper, web environments are analyzed in detail, by looking at low level components of the environment architecture, and questioning the benefits of basic building blocks and whether they are designed and implemented to provide optimal performance. We believe that the current building blocks of web environments are used as standardized components to build on top of, believing that they provide the best performance, ending up with a nice creature, which has a lot of virtues but lacking performance. Better performance can be obtained with some customized changes to its building blocks.
Keywords: Multi-Channel, Web application Server, Clustering, High Availability, Service State Migration, High Performance Computing, High Performance Agent, Skeleton Caching, Containers, Hybrid Scripting.
Full Text (.pdf)  International Journals Of Engineering and Science| 1,874 KB
Title: Preliminary Study of Circularly Split Ring Resonators Entrenched within Circular Microstrip Antenna
Author(s): A. A. M. Ezanuddin, M. F. Malek, P. J. Soh
Pages: 26-36 Paper ID: 112902-8383-IJET-IJENS Published: April, 2011
Abstract: In this paper, influence of Circularly Split Ring Resonators with its accompanying circular microstrip patch antenna are investigated. Proposing a 5850 to 7075 MHz band of working frequency, by means of microwave laminate RT/D 5880 (er = 2.2 and thickness of 1.82 mm). The antenna is wholly organized into three layers consisting of circular copper sheet as ground plane, an undersized main radiator for where signal will pass through to resonate and ended with designed split rings entrenched on layer three laminate. All layers are separated by an air gap, simulated and optimized carefully using Microwave Studio of Computer Simulation Technology Suite (CST). Provided that, dimension of air gap, split ring quantity and entrenched split ring width are monitored as key controllers. Via transient solver, it presents corresponding S-parameter results and provides 3D view farfield. Thus demonstrating how each key controllers influence the antenna in terms of bandwidth, directivity, gain and efficiency produced. These works conclude that adaptation of split rings can enhance and improve this particular antenna.
Keywords: CCSRRs, CMS, CSMA, SRR.
Full Text (.pdf)  International Journals Of Engineering and Science| 1,925 KB
Title: The Development of Hybrid Surge Protection Circuit with Effect of Adding a Filter
Author(s): Amizah Md Ariffen, Mohd Zainal Abd Kadir, Wan Fatinhamamah Wan Ahmad
Pages: 37-44 Paper ID: 113502-0909-IJET-IJENS Published: April, 2011
Abstract: Surge protective device is a part of internal lightning protection and it crucially to divert the certain amount of surges to the ground before the protected load able to handle. Therefore, this paper studying the enhancement of SPD through the effect of adding a filter in hybrid surge protection circuit using simulation modeling. Ordinarily, filter is used as in eliminating noises in certain application such as electronic apparatus. Furthermore, an experiment testing is pursues in high voltage laboratory for comparison and to validate the simulation. The analysis involved the surge protector Class 3 according to IEC or Category A as referring to IEEE standards with a filter design involving the combination of inductor and capacitor. From this research is found that a significant improvement of about 38% obtain when filter is added in surge protective device.
Keywords: Surge protector, transient voltage suppressor diode, metal oxide varistor, hybrid protection, surges, EMI filter.
Full Text (.pdf)  International Journals Of Engineering and Science| 588 KB
Title: A hydrographic study of Ras Hatiba Lagoon, Red Sea
Author(s): Alaa M. A. Albarakati
Pages: 45-57 Paper ID: 114402-0707-IJET-IJENS Published: April, 2011
Abstract: Ras Hatiba Lagoon is been classified by Presidency of Meteorology and Environment (PME) of Saudi Arabia with the collaboration of International Union for Conservation of Nature and Natural Resources (IUCN) as an environmentally sensitive area. This study is considered to be a baseline study for Ras Hatiba Lagoon. The lagoon is located at the eastern coast of the Red Sea. It is shallow with an average depth of 2m. Tidal force is dominating the water circulation in the lagoon.
Keywords: Saline, Lagoon, Red, Sea, Model, Tide.
Full Text (.pdf)  International Journals Of Engineering and Science| 502 KB
Title: Estimation of Peak Power Density in the Vicinity of Cellular Base Stations, FM, UHF and WiMAX Antennas
Author(s): Bexhet Kamo, Rozeta Miho, Vladi Kolici, Sanie Cela, Algenti Lala
Pages: 58-64 Paper ID: 116402-7575-IJET-IJENS Published: April, 2011
Abstract: Estimation of peak power density, in the vicinity of cellular base stations, FM, UHF and WiMAX antennas, and comparison of theoretical values with exposure limits for public and occupational, offers the possibility of knowing the safety distance from those antennas. Results of estimations, for the peak power density radiated from antennas, are given by eliminating or not considering reflected waves from different surfaces. By simplifying the method of theoretical calculation, we can have values which, for relatively small distances from the antennas, are almost real. The safety distances, from those antennas, are estimated for real frequencies and applications in order to have a clear idea for the safety distances.
Keywords: Antennas, base station, non ionizing radiation, safety distance.
Full Text (.pdf)  International Journals Of Engineering and Science| 337 KB
Title: Catalytic Conversion of Acetone to Monoaromatic Chemicals using HZSM-5
Author(s): Setiadi, Slamet, Mohammad Nasikin
Pages: 65-72 Paper ID: 118302-6464-IJET-IJENS Published: April, 2011
Abstract: The effects of process variables (temperature, space velocity, water addition and Si/Al ratio) on the conversion of acetone to aromatic chemicals have been investigated. The reaction is carried out by fixed bed reactor at an atmospheric pressure to examine the activity and selectivity of HZSM-5. The results show that HZSM-5 exhibited a high active and a shape-selective catalyst for the formation of monoaromatic chemicals. The favourable condition for acetone aromatization is found i.e. at 673 K with space velocity of 4 h-1, the acetone conversion is close to 100 % and monoaromatic selectivity is approximately 71 %. There is no effect of water existence in the acetone feed on the aromatization reaction process, making the process will be simplified. A significant effect of Si/Al ratio on the activity of HZSM-5 on the durability reaction test for 10 h reaction in a fixed bed reactor at 673 K, space velocity of 4 h-1. The acetone conversions with Si/Al ratio of 25 were much better than those of other ratios during 10 h of reaction. Over HZSM-5 with Si/Al ratio of 75 or 100, the acetone conversion and the monoaromatic selectivity were gradually decreased after 10 h of reaction. It can be concluded that the acetone conversion to monoaromatic chemicals requires a high acid density.
Keywords: Acetone conversion, monoaromatic, HZSM-5, Si/Al ratio.
Full Text (.pdf)  International Journals Of Engineering and Science| 437 KB
Title: Modification of TiO2 Nanoparticle with PEG and SiO2 For Anti-fogging and Self-cleaning Application
Author(s): Dewi Tristantini, Slamet, Rini Mustikasari, Widuri
Pages: 73-78 Paper ID: 1110702-8383-IJET-IJENS Published: April, 2011
Abstract: Photocatalytic process over TiO2 has been developing and employed in many applications. One of its applications is used as self-cleaning and anti fogging material. The hydrophilic properties of its material allow water to spread completely across the surface rather than remaining as droplets so it can perform self-cleaning and anti-fogging effects. Some studies have been done to enhance the performance of this photocatalyst by using kinds of additives. In this study, PEG and SiO2 are used simultaneously and added to TiO2 photocatalyst that prepare by using TiAcAc precursor. The addition of these additives is varied in composition until optimum condition achieved. From SEM, BET, XRD, and FTIR characterization and also activity test by using contact angle meter, optimum condition was achieved in addition of PEG 15% weight and SiO2 30% weight. In this composition, catalyst can perform self cleaning and anti fogging effects even in minimum light condition. Combination of PEG and SiO2 addition can also improve catalyst performance such as crystal structure, crystal size, porosity and surface area.
Keywords: Nano particle, TiO2, hydrophilic, PEG, SiO2, self-cleaning, anti fogging.
Full Text (.pdf)  International Journals Of Engineering and Science| 635 KB
Title: High Pressure Adsorption of Methane and Hydrogen at 25 oC on Activated Carbons Prepared from Coal and Coconut Shell
Author(s): Mahmud Sudibandriyo
Pages: 79-85 Paper ID: 119002-6363-IJET-IJENS Published: April, 2011
Abstract: The long term objective of the study is to obtain suitable adsorbents to be applied for methane and hydrogen storage. In this case, a detailed experimental study has been made of the adsorption of pure methane and hydrogen at 25 oC and pressures up to 6 MPa on dry activated carbons prepared from coal and coconut shell. Measurements were made using a volumetric technique. The highest adsorption is obtained for the activated carbon prepared from coal with the ratio of KOH: coal = 4:1 at activation temperature 900o C, i.e. 7 mmol/g for methane adsorption and 1.4 mmol/g for hydrogen adsorption. The data were correlated using the Ono-Kondo lattice model. The model fits the pure-component adsorption data well within their experimental uncertainties. The results also indicates that the adsorption capacity is proportional to the surface area of the activated carbon, however smaller pore size is needed for more proper adsorption of hydrogen.
Keywords: Activated Carbon, Adsorption, High-pressure, Hydrogen, Methane.
Full Text (.pdf)  International Journals Of Engineering and Science| 623 KB
Title: Mechanism of the Char Reduction Reaction in a Staged Gasification: Sensitivity of Water Gas Shift Reaction
Author(s): Suyitno, Thoharudin, Bobie Suhendra
Pages: 86-93 Paper ID: 119102-8686-IJET-IJENS Published: April, 2011
Abstract: Wood biomass of two different moisture contents, i.e. 15 wt% and 98 wt% was gasified in a staged gasifier. The produced gas from oxidation zone at maximum temperature 1373 K reacted with char from pyrolysis in the reduction reactor. Some additional air was needed in order to increase the char conversion rate and to keep high enough temperature in the reactor. The possible reaction mechanism was investigated via computational fluid dynamics (CFD). Four different reaction constants of water gas shift reaction (wgsr) for order 1.5 and for order 2 were validated and their sensitivities were investigated. It was found that the reaction rate of wgsr was very sensitive to the steam concentration. The gas composition and temperature profile from simulation via 11 reactions was more realistic than from simulation via 10 reactions if compared to the experimental data. The mechanisms of wgsr and water gas reaction-secondary steam gasification (wgr-ssg) have to be taken into account particularly in char reduction simulation at high moisture content.
Keywords: CFD, char reduction, staged gasification, water gas reaction, water gas shift reaction.
Full Text (.pdf)  International Journals Of Engineering and Science| 441 KB
Title: Phase Equibria in the System Ga-Ni-Sb at 500oC
Author(s): Sutopo
Pages: 94-100 Paper ID: 119402-6868-IJET-IJENS Published: April, 2011
Abstract: Phase equilibria were established in the Ga-Ni-Sb system at 500 oC using X-ray diffraction and electron probe microanalysis. GaSb was shown to be in thermodynamic equilibrium with gallium, NiSb2, NiSb, and Ni2Ga3. Owing to undesirable intrinsic properties, none of these phases is suitable as a contact material to GaSb or to a compound semiconductor alloys containing GaSb as a constituent. Nickel is not in thermodynamic equilibrium with GaSb and therefore is not suitable as metallization agent. Both NiSb and Ni2Ga3 have shown to be in equilibrium with GaSb.
Keywords: Electron probe micro analysis, NiAs structure, Phase diagram, Ga-Ni-Sb system, X-ray diffraction.
Full Text (.pdf)  International Journals Of Engineering and Science| 464 KB
Title: A Proposed Routing Protocol for MANET
Author(s): Mamoun Hussein Mamoun
Pages: 101-105 Paper ID: 1110102-9393-IJET-IJENS Published: April, 2011
Abstract: Many routing protocols have been designed for Ad Hoc networks. However, most of these kinds of protocols are not able to react fast enough to maintain routing. This paper presents a Proposed Routing Protocol (PRP) that repairs the broken route by using information provided by nodes overhearing the main route communication. When links go down, our protocol intelligently replaces these failed links or nodes with backup ones that are adjacent to the main route. Experimental results show that our protocol finds a backup route around 50% of cases and achieve better performance in term of the packet delivery rate than the major Ad Hoc routing protocols, but with much less overhead.
Keywords: MANET, DSR, New routing protocol for MANET.
Full Text (.pdf)  International Journals Of Engineering and Science| 356 KB
Title: Improper Fuse Wire Replacement, and Possible Association with Commercial Fires
Author(s): Shahriar Khan
Pages: 106-110 Paper ID: 114802-9393-IJET-IJENS Published: April, 2011
Abstract: The rewireable fuse or cutout is widely used in Bangladesh and elsewhere, in spite of the very real danger of improper replacement of fuse wires. To assess the problem, a preliminary survey of buildings, electrical shops, and electricians were conducted. The majority of buildings and retail establishments were found to use fuse wires. Electricians were found to use copper of arbitrary thicknesses as fuses, and were unaware of the existence of specialized fuse wires. Every year, there are numerous fires in the garments and other industries, causing hundreds of deaths. As the vast majority of these fires are of electrical origin, the evidence is strong that improper fuse wiring may have been the cause of the fires. The number of smaller fires which do not make it to the news is likely to be orders of magnitude greater than the publicized fires. Even when the origin is not electrical, insulation failures may cause secondary electrical fires, that may cause the fire to spread rapidly to the rest of the building, making it hard to extinguish.
Keywords: Fuse, wire, cutout, industry, fires.
Full Text (.pdf)  International Journals Of Engineering and Science| 303 KB
Title: A Physical Method Applied for Preparing Radiopharmaceutical Kits
Author(s): Merita Alikaj
Pages: 111-120 Paper ID: 117702-1616-IJET-IJENS Published: April, 2011
Abstract: This article presents the project of radiopharmaceutical production using physical methods, the one of sublimation. The application of this method makes possible that this freezes dried kit (sublimated) has a long life. In this study we emphasize the physical basis of sublimation liophylization, as well as the need of using this technique in nuclear medicine and more specifically, the production of MIBI kit. Nowadays, this method is used not only for the maintenance, but also for the production in laboratory and industrial conditions, in pharmaceutical industries etc. Liofilization is potentially applicable in medicine. It is thought that this method can be used even in preserving organs for transplantation and there are more connections with radiopharmaceutical and pharmaceutical production.
Keywords: Radiopharmaceutical Kits, Sublimation
Full Text (.pdf)  International Journals Of Engineering and Science| 882 KB
Title: Contradictions in the Definition, Creation, and Existence of Black Holes
Author(s): Shahriar Khan
Pages: 121-129 Paper ID: 117102-9898-IJET-IJENS Published: April, 2011
Abstract: Although general relativity is mostly verified in astronomy, it leads to the black hole as a solution to Einstein’s field equations; a solution that also contradicts much of the known laws of physics. The study of black holes can be traced as attempts to reconcile them with some laws of physics, which lead to more contradictions with other laws. The inherent contradictions have led to imaginative and poetic theories, such as nature hiding a singularity behind an event horizon. Even in this day of astronomy and telescopes, there is no conclusive proof of the existence of black holes. The supermassive body at the center of our galaxy is surprisingly calm, hardly the dramatic accretion disk expected of a supermassive black hole. Thought experiments not very different from those that established general relativity, are used in this paper to identify the contradictions that arise from the black hole solution to Einstein’s field equations. The event horizon is seen to have unresolved singularities, and is only valid for a body with zero verlocity and energy in far away space. The horizon diminishes to a traveler approaching a black hole, and the horizon enlarges for a body with a finite velocity in far-away space. The principle that an outside observer would never see a body enter the event horizon, implies that to the outside world, no black hole has ever been created or will ever be created. An observer would sense the increase in mass of the black hole from falling matter, while never seeing the matter actually fall inside; thus sensing the mass and gravity twice. A black hole collapsing towards singularity may radiate ever increasing energy because of increasing rotation. These suggest that the solution of a black hole of Einstein’s field equations may need modification, or is trivial, without physical relevance. The elusive nature of black holes, and the absence of concrete evidence of existence even in this age of telescopes and astronomy, suggest that general relativity is no longer applicable in extreme gravity, such as in the case of a star collapsing into a black hole. A simplistic alternative is proposed, so as to avoid the singularities inherent in the event horizon and Black hole.
Keywords: General relativity, black hole, event horizon, singularity, supermassive, astronomy, Schwarzschild radius.
Full Text (.pdf)  International Journals Of Engineering and Science| 478 KB
Title: Performance of A Laboratory Static Var Compensator
Author(s): Maamar Taleb, Mustafa Ibrahim Hasan, Mahmood Marzooq Mansoor
Pages: 130-133 Paper ID: 118002-7474-IJET-IJENS Published: April, 2011
Abstract: This paper presents a laboratory model for a shunt static var compensator (SVC). Such shunt static var compensator (SVC) is useful in the control of power distribution feeders. The type of the SVC considered in this investigation is the famous thyristor-controlled reactor (TCR) configuration. LABVIEW software has been used as a practical platform to control the operation of the SVC thyristors. For a labratory load voltage fluctuating originally between 265 V at light loading and 240 V at heavy loading, a near 240 V as an rms value was kept constant at the feeder terminals. That was observed when installing the SVC and changing randomly the level of the feeder loading. The introduction of the SVC resulted in some distortion in the load voltage waveform but luckly the measured total harmonic distortion factor (THD) was found to be below the allowed levels reported in relevant IEEE power quality standards.
Keywords: Static Voltage Compensators, Power System Harmonics, LABVIEW Applications, Electrical Engineering Education.
Full Text (.pdf)  International Journals Of Engineering and Science| 358 KB
Title: Reducing Peak Electricity Demand through 300MW Wind Farm North of Jeddah, Saudi Arabia
Author(s): Ramzy R. Obaid
Pages: 134-140 Paper ID: 1110802-5454-IJET-IJENS Published: April, 2011
Abstract: The drastic increase in electricity demand over the last decade has been putting a huge burden on the Saudi utility company to plan ahead and guarantee continuous power supply to its customers. Private investments in power generation are being solicited and encouraged to contribute significantly to the power grids and alleviate the burden of meeting the surge in power demand. Jeddah, the second largest city in the Kingdom, is located in the western region, which is a major component of the power grid. Power generation plants in Saudi Arabia are conventional fossil-fuel thermal plants; therefore, the addition of a wind farm north of Jeddah would be greener to Earth, have a significant effect on power generation, and relieve the utility company from a considerable chunk of its peak demand obligation.
Keywords: DSM, Electricity Demand, Renewable Energy, Saudi Arabia, Wind Farms.
Full Text (.pdf)  International Journals Of Engineering and Science| 419 KB
Title: Comparative Analysis of Routing Technologies in Next Generation Converged IP Network
Author(s): Ibikunle Ayoleke F., Sarumi Jerry A., Shonibare Emmanuel O.
Pages: 141-150 Paper ID: 119502-7474-IJET-IJENS Published: April, 2011
Abstract: Next Generation Network (NGN) services is a phenomena innovation that brought to maturity the market for high speed Internet and general integration of communication services. This has led to affordable services that offer end-users considerable savings in their expenditure for such services. The demand for these applications and services shows the failings of the currently used network technologies. NGN are internet technologies-based, with respect to Internet Protocol (IP) and Multi-Protocol Label Switching (MPLS). This technology had made service providers to have been under increasing pressure to deliver various services to their customers with a great deal of high speed, scalability, Quality of Service (QoS), Traffic engineering, and at low cost. This paper by computer modelling and simulations compares the routing technologies (i.e., IP, MPLS and ATM) in a converged IP network in terms of their routing capabilities based on different metrics.
Keywords: NGN, IP, MPLS, ATM, VPN, Routing.
Full Text (.pdf)  International Journals Of Engineering and Science| 830 KB