bluuebunny/crossref_metadata_2025 huggingface dataset:
Availability Of Literature On Engineering Ethics In The Internet
Authors: Suhaimi Mhd Sarif Yusof Ismail,
Published: October 2018

Internet is becoming a popular tool among career-oriented people. Among professionals, some of the engineers use the Internet in their work to search for information. The study is carried out to ascertain comparative availability of the materials on ethics and engineers in four top Internet search engines (ISE’s). Four ISE’s were accessed on 2 February 2011, from 2.21 p.m. to 4.21 p.m. [Gombak Time] using a combination of selected search terms: education, engineer, engineering, ethics, Islam, professional, research, and training. The search results or hits produced by the selected ISE’s were analyzed using a specially created instrument/format. The study computes relative ratios of the coverage of selected terms in relation to the number of hits for selected terms within each ISE. The ratios are obtained by dividing the hits for a search term or combination into the total hits within each ISE. The results of the analysis reveal that the ISE’s contain the highest frequency of materials on engineers and ethics. The findings suggest to engineering students and practitioners of varying capabilities among the ISE’s used in the study to learn about engineering ethics. Limitations of the study and suggestions for further research are included in the study.   ABSTRAK: Internet menjadi alat yang popular di kalangan staf yang berorientasikan kerjaya. Di kalangan profesional, para jurutera menggunakan Internet untuk mencari maklumat dalam kerja-kerja mereka. Kajian ini dijalankan untuk menentukan ketersediaan perbandingan bahan-bahan mengenai etika dan jurutera dalam empat enjin carian Internet (ISE) teratas. Beberapa ISE dicapai pada 2 Februari 2011, di antara 2.21 petang sehingga 4.21 petang [waktu Gombak] menggunakan gabungan terma carian yang dipilih: pendidikan, jurutera, kejuruteraan, etika, Islam, profesional, penyelidikan, dan latihan. Keputusan carian atau ‘hits’ yang dihasilkan oleh ISE terpilih telah dianalisis dengan menggunakan instrumen/format yang direka khas. Kajian itu mengira nisbah relatif liputan terma-terma terpilih tersebut dengan jumlah ‘hits’ bagi kesemua terma bagi setiap ISE. Nisbah diperolehi dengan membahagikan ‘hits’ bagi istilah carian atau gabungan istilah dengan jumlah ‘hits’ dalam setiap ISE. Keputusan analisis menunjukkan ISE yang mengandungi kekerapan tertinggi bahan-bahan berkaitan dengan jurutera dan etika. Hasil kajian menyarankan kepada pelajar-pelajar dan pengamal kejuruteraan bahawa wujud keupayaan yang berbeza-beza di kalangan ISE berhubung dengan potensi bahan-bahan berkaitan etika kejuruteraan. Batasan kajian dan cadangan untuk penyelidikan selanjutnya dimasukkan dalam kajian ini.  Keywords-engineering ethics; internet search engines; literature; training and development
Kinematic Analysis Of Tricept Parallel Manipulator
Authors: Hosseini Mir Amin , Mohammadi Daniali Hamid-Reza
Published: October 2018

Parallel manipulators consist of fixed and moving platforms connected to each other with some actuated links. They have some significant advantages over their serial counterparts. While, they suffer from relatively small workspaces, complex kinematics relations and highly singular points within their workspaces. In this paper, forward kinematics of Tricept parallel manipulator is solved analytically and its workspace optimization is performed. This parallel manipulator has a complex degree of freedom, therefore leads to dimensional in-homogeneous Jacobian matrices. Thus, we divide some entries of the Jacobian by units of length, thereby producing a new Jacobian that is dimensionally homogeneous. Moreover, its workspace is parameterized using some design parameters. Then, using GA method, the workspace is optimized subjects to some geometric constraints. Finally, dexterity of the design is evaluated. Keywords- Kinematic, Workspace, Singularity, TriceptABSTRAK - Manipulator selari terdiri daripada platform tetap dan bergerak yang bersambung antara satu sama lain dengan beberapa pautan bergerak. Manipulator selari mempunyai beberapa kebaikan tertentu dibandingkan dengan yang bersamaan dengannya. Walaupun ia mempunyai ruang kerja yang sempit, hubungan kinematik kompleks dan titik tunggal tinggi dalam linkungan ruang kerjanya. Dalam kajian ini, kinematik ke hadapan manipulator selari Tricept diselesaikan secara analisa dan pengoptimuman ruang kerja dijalankan. Manipulator selari ini mempunyai darjah kebebasan yang kompleks, yang menyebabkan ia mendorong kepada kehomogenan dimensi matriks Jacobian. Catatan Jacobian dibahagikan kepada unit panjang, dimana ia menghasilkan Jacobian baru yang homogen dimensinya. Tambahan, ruang kerjanya diparameterkan dengan menggunakan beberapa parameter reka bentuk. Kemudian, dengan kaedah GA, ruang kerja mengoptimakan subjek kepada beberapa kekangan geometrik. Akhirnya, kecakatan reka bentuk dinilaikan.Keywords- Kinematic, Workspace, Singularity, Tricept
DEVELOPMENT OF VIRTUAL ASSEMBLY LAYOUT WITH MODELING LANGUAGES APPROACH AND SIMULATION USING DELMIAâ„¢ QUESTÂ®
Authors: Mohamad Norhidayah , H.M. Yupiter , J. Roseleena , A. Shaharudin , Y.A. Erry
Published: October 2018

ABSTRACT: The paper presented the development of virtual layout model with modeling languages approach. This research also explores the flexibility of the model configurations through the development process of database for storing and representing the virtual model. The concept and mechanisms of database development involves the use of eXtensible Markup Language (XML). The objectives of the research are therefore to obtain a basic understanding on how these modeling languages are used to develop virtual model, representing the simulation by using Delmiaâ„¢ QUESTÂ® and develop a database for share, store and future usage. Therefore, the generated simulation presents the feasibility of interchanging models using modeling language approach as an intermediate representation and provides an opportunity to improve simulation quality.
AN INVESTIGATION ON SOFT MAGNETIC AND NON-MAGNETIC MATERIALS UNDER LOW FREQUENCY FOR BIOMEDICAL SENSOR APPLICATION
Authors: Khan Sheroz
Published: October 2018

In consequence of the recent development of magnetic sensors in biomedical sector, the investigation of magneticmaterials has been a contributing factor in application stage. This paper proposes a novel technique to investigate materials by obtaining unique distinctive impedance peaks with unique impedance values. A magneto-inductive sensoris used to measure the induction of magnetic and non-magnetic impedance peaks related to the change in permeability, thus characterizing the materials under low frequency.
Convection Heat Transfer Modeling of Ag Nanofluid Using Different Viscosity Theories
Authors: Kasaeian Ali Bakhsh
Published: October 2018

ABSTRACT: In this paper, the effects of adding nanoparticles (including Ag) to a fluid media for improving free convection heat transfer were analysed. The free convective heat transfer was assumed to be in laminar flow regime, and the corresponding calculations and solutions were all done by the integral method. Water, as a Newtonian fluid, was considered as the base and all relevant thermo physical properties of the nanofluids were considered to be unvarying. The calculations performed and the graphs generated showed that, in general, the addition of nanoparticles to the fluid media resulted in an increment or improvement of its heat transfer coefficient. With increase in the concentration of the nanoparticles, the heat transfer rate of the fluid also increased. The increment in heat transfer is also dependent on the nanoparticlesâ€™ thermal conductivity and the viscosity theory which was utilized in the calculations. In this study, four different theories were used to calculate the viscosities of the nanofluids. The effects of viscosity on the nanofluidsâ€™ thermal conductivity were apparent from the calculations which were performed for nanoparticle concentrations of 4% or less.Â ABSTRAK: Kajian ini menganalisis kesan penambahan nanopartikel Ag ke dalam media bendalir bagi tujuan pembaikkan pemindahan haba perolakan bebas. Perolakan bebas diandaikan berada di zon aliran laminar, di mana penyelesaian dan pengiraan telah dilakukan mengunakan kaedah kamilan. Air yang merupakan cecair Newtonian, dianggap sebagai asas dan sifat terma fizikal nanocecair dianggapkan tidak berubah. Mengikut pengiraan yang dilakukan dan graf yang diplotkan, umumnya penambahan nanopartikel kepada media bendalir menyebabkan peningkatan dan pengembangan pekali pemindahan haba. Kadar pemindahan haba meningkat dengan nanopartikel. Peningkatan pemindahan haba juga bergantung kepada pengalir haba nanopartikel dan teori kelikatan yang digunakan. Di dalam kajian ini, empat jenis teori telah digunakan bagi pengiraan kelikatan nanopartikel. Kesan kelikatan ke atas pengalir haba nanocecair sangat jelas kelihatan. Kesemua pengiraan telah dilakukan ke atas kepekatan kurang dari 4%.KEYWORDS: Ag nanofluid, heat transfer, natural convection.
The Parameters Affect on Power Coefficient Vertical Axis Wind Turbine
Authors: Qasim Ahmed Y. , Usubamatov Ryspek , Zain Zuraidah M. , Quad Ghulam Abdul
Published: October 2018

ABSTRACT: This study describes the design of a special type of vertical axis rotor wind turbine with moveable vertically positioned vanes. The novel design increases the torque in the left side of the wind turbine by increasing the drag coefficient. It also reduces the negative torque of the frame which rotates contrary to the wind in the other side. Two different types of models, having different vane shapes (flat vane and cavity shaped vane), were fabricated. Each type consisted of two models with varying number of frames (three and four frames). The models were tested in a wind tunnel with variable wind speed in order to understand the effect of shape, weight, and number of frames on the power coefficient of the wind turbine.Â ABSTRAK: Di dalam kajian ini, rotor turbin angin berpaksi vertikel sebagai rangka khusus telah direkabentuk dengan lokasi vertikel mudahalih oleh bilah kipas. Rekabentuk ini meningkatkan tork di bahagian kiri turbin angin dengan meningkatkan pekali seretan dan mengurangkan tork negatif rangka yang berputar berlawanan dengan angin pada bahagian lain. Dua jenis model berbentuk berlainan telah difabrikasi (bilah kipas rata dan bilah kipas berbentuk kaviti), dengan setiap jenis mempunyai dua model dengan bilangan rangka yang berlainan (berangka tiga dan berangka empat). Model-model telah diuji di dalam terowong angin dengan kelajuan angin yang berbeza bagi mendapatkan kesan rekabentuk, berat dan bilangan rangka ke atas pekali kuasa.KEYWORDS: design; wind turbine; drag coefficient; vane
PROCESS MODELLING AND DEBOTTLENECKING STUDY OF A VACCINE PRODUCTION
Authors: Mohamed Safri Nurul Huda , Mel Maizirwan , Foo Dominic C.Y. , Ng Denny K.S. , Chew Irene M.L.
Published: October 2018

ABSTRACT: The main objective of this research work was to model and optimise the production of a locally-developed Infectious Coryza (IC) vaccine. The simulation work was performed using a commercially available batch process simulator SuperPro Designer v5.5.Â Six debottlenecking schemes were analysed using throughput analysis and cost to benefit ratio (CBR) when the annual production was set to increase by 100%. Based on the economic analysis, the selected debottlenecking scheme has an annual predicted revenue of USD 240 million, with a gross margin of 9.13% and a return on investment (ROI) of 46.12%. In addition, the payback period of the selected scheme is estimated to be within three years.Â ABSTRAK: Objektif utama dalam penyelidikan ini adalah untuk memodelkan dan mengoptimumkan hasil pembuatan vaksin tempatan Coryza berjangkit. Kerja simulasi ini dijalankan menggunakan alat simulasi Super Pro Designer v5.5. Sebanyak enam (6) skema khusus diujikaji menggunakan analisis pemprosesan dan kos kepada nisbah faedah (CBR) apabila pembuatan tahunan meningkat kepada 100%. Berdasarkan analisis ekonomi yang telah dilakukan, sesuatu skema khusus yang dipilih mempunyai keuntungan sebanyak USD 240 juta dengan margin kasar 9.13% dan pulangan atas pelaburan (ROI) sebanyak 46.12%. Selain itu juga, tempoh pembayaran balik bagi skema yang dipilih dianggarkan dalam tempoh tiga(3) tahun.KEYWORDS: process simulation; modelling; debottlenecking; optimisation
Investigation of Residual Stresses and Distortion in Welded Pipe-Flange Joint of Different Classes
Authors: Abid Muhammad
Published: October 2018

ABSTRACT: Pipe and flange joints are commonly used in petrochemical, nuclear and process industries. Commonly, welding is used to make these joints which produces residual stresses and distortions. These stresses have detrimental effects on the structural integrity and service performance of the welded pipe joints. The objective of this study is to investigate the residual stresses and distortions during Gas Metal Arc Welding of pipe of schedule 40, nominal diameter 200 mm with different ANSI flanges of class numbers 150, 300, 600, 900, 1500, and 2500. Welding parameters including: voltage, current and heat as inputs were selected based on the literature available. The behaviour of the flanges of different classes is also discussed. In addition, the finite element methodology presented, in this paper, can be helpful for developing welding procedures for a range of pipe flange welded joint sizes in order to control the residual stresses and deformations. This will lead to optimised performance during bolt up and operating conditions.ABSTRAK: Paip dan sambungan flan biasanya digunakan dalam industri petrokimia, nuklear dan proses. Kimpalan menghasilkan tegasan sisa dan herotan, yang memberikan kesan yang merbahaya ke atas integriti struktur dan prestasi servis sambungan kimpalan paip. Objektif kajian ini adalah untuk mengkaji tegasan sisa dan herotan ketika kimpalan arka logam gas paip berjadual 40, diameter nominal 200mm dengan flan ANSI yang berbeza kelas # 150, 300, 600, 900, 1500, dan 2500. Parameter kimpalan termasuklah; voltan, arus dan haba input yang dipilih berdasarkan literatur sediada. Kelakuan flan yang berbeza kelas telah dibincangkan. Kaedah elemen finit yang dibentangkan adalah berguna dalam membangunkan prosedur kimpalan bagi julat saiz kimpalan flan paip unutk mengawal tegasan sisa dan canggaan i.e. bagi mengoptimakan prestasi ketika bolt up dan sedang beroperasi.Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â KEYWORDS:Â finite element; residual stresses; distortion; welding; pipe-flange joint; different classes
Optimizing PHB and Protease Production by Box Behnken Design
Authors: Amara Amro Abd al fattah
Published: October 2018

Mixed culture is more suitable to adapt more flexible fermentation process and produce different product simultaneously. In this study a mixed Bacillus culture was investigated for their ability to produce the bioplastic "Polyhydroxybutyrate" and both of the mesophilic and the thermophilic proteases in one flask. Box-Behnken experimental design was used. The produced amount of PHB has been increased significantly. Meanwhile there is a competition between PHB and proteases. The maximum produced amount of PHB using Box-Behnken design was 2.82 g/l/48 h with protease activity equal to 41.9 Units/ml/48 h for thermophilic proteases and 99.65 Units/ml/48 h for mesophilic proteases. Excel solver was used for extra-optimization for the optimum conditions obtained from Box-Behnken experiments and its model. The maximum PHB obtained after using Excel solver was 2.88 g/l/48 h. The maximum mesophilic and thermophilic activities obtained at the same PHB production conditions were 175.68 and 243.38 Units/ml respectively. The model accuracy as obtained from Excel solver was 118.8%, which prove the power of the experimental design in optimizing such complicated process. The strategies used in this study are recommended for the production of PHB and different proteases simultaneously using Bacillus mixed culture. ABSTRAK: Kultur campuran adalah lebih sesuai bagi proses penapaian yang fleksibel dan ia boleh menghasilkan produk yang berbeza secara serentak. Dalam kajian ini keupayaan  menghasilkan "Polyhydroxybutyrate" bioplastik serta mesofilik dan termofilik protease dalam satu flask oleh  kultur Bacillus campuran telah disiasat. Eksperimen rekabentuk Box-Behnken telah digunakan. Jumlah PHB yang dikeluarkan meningkat dengan ketara dan terdapat persaingan antara PHB dan protease. Jumlah keluaran PHB maksima menggunakan rekabentuk Box-Behnken adalah 2.82 g/l/48 jam dengan aktiviti protease sama dengan 41.9 Unit/ml/48 jam untuk protease termofilik dan 99.65 Unit/ml/48 h untuk protease mesofilik. Solver Excel telah digunakan untuk memperolehi kadar optimum tambahan dari keadaan optimum yang diperolehi dari experimen dan model Box-Behnken. PHB maksimum diperolehi setelah menggunakan solver Excel adalah 2.88 g/l/48 jam. Aktiviti mesofilik dan termofilik maksima diperolehi daripada keadaan pengeluaran PHB yang sama adalah 175.68 dan 243.38 Unit / ml. Ketepatan model diperolehi daripada solver Excel adalah 118.8%, membuktikan kekuatan eksperimen tersebut bagi mengoptimumkan proses yang rumit. Strategi yang digunakan dalam kajian ini adalah disyorkan bagi pengeluaran PHB dan proteas berbeza secara serentak menggunakan kultur Bacillus campuran.KEYWORDS: PHB; proteases; mixed culture; Box-Behnken design.
Estimation of Solar Radiation: An Empirical Model for Bangladesh
Authors: Bhuiyan Mohammad Arif Sobhan
Published: October 2018

This study is carried out to compute empirically global, diffuse and direct solar radiation on a horizontal surface for the ten districts equally distributed all over Bangladesh (20o34Î„and 26o34Î„north latitude, 88o01Î„ and 92o41Î„east longitude) as well as to predict correlations for them. For this study, meteorological data for 28 years (between 1980 and 2007) is used which is collected from Bangladesh Meteorological Department. The global radiation in Bangladesh is found to be maximum in the month of April/May and minimum in the month of November/December in all the districts. The values of the correlation coefficients a, b, c, d, c', d', e, f, e' and f' for ten stations of Bangladesh are also evaluated. It is evident that, the values of the coefficient “a” vary from 0.2296 to 0.2569, while the coefficient “b” varies from 0.5112 to 0.5560. The over all mean deviations of the ten values of a and b are 0.2432±0.0136 and 0.5336±0.0224, respectively. The maximum and minimum values of other correlation coefficients c, d, c', d', e, f, e' and f' are (1.5695 and 1.4357), (-1.7210 and -1.9986), (0.4011 and 0.376), (-0.2072 and -0.2510), (-0.3811 and -0.5464), (1.946 and 1.6456), (-0.1206 and -0.1684) and (0.7984 and 0.7000) respectively. Their maximum variations due to location are (1.5022±0.0672), (-1.8598±0.1388), (0.3885±0.0125), (-0.2291±0.0219), (-0.4637±0.0826), (1.7958±0.1502), (-0.1445±0.0239) and (0.7492±0.0492) respectively. ABSTRAK: Kajian ini dibuat secara empirikal mengenai kadar penyebaran secara resapan, global dan langsung radiasi solar, keatas permukaan mendatar untuk sepuluh daerah di seluruh Bangladesh (20o34Î„ dan 26o34Î„ utara latitud, 88o01Î„ dan longitud 92o41Î„ timor) dan meramal korelasi mereka. Kajian ini menggunakan data meteorologi selama 28 tahun (antara 1980 dan 2007) yang dikutip dari Jabatan Meteorologi Bangladesh. Radiasi global maksima di Bangladesh adalah pada bulan April / Mei dan minima pada bulan November / Disember di semua daerah. Kajian dibuat mengenai nilai pekali korelasi a, b, c, d, c', d', e, f, e' dan f' bagi sepuluh stesen di Bangladesh. Nilai pekali "a" adalah antara 0.2296 dan 0.2569, manakala pekali "b" adalah antara 0.5112 dan 0.5560. Sisihan min keseluruhan bagi sepuluh nilai a dan b adalah 0.2432 ± 0.0136 dan 0.5336 ± 0.0224. Nilai maksima dan minima pekali korelasi lain c, d, c', d', e, f, e' dan f' adalah (1.5695 and 1.4357), (-1.7210 dan -1.9986), (0.4011 dan 0.376), (-0.2072 dan -0.2510), (-0.3811 dan -0.5464), (1.946 dan 1.6456), (-0.1206 dan -0.1684) dan (0.7984 dan 0.7000). Variasi maksima antara mereka disebabkan lokasi adalah (1.5022±0.0672), (-1.8598±0.1388), (0.3885±0.0125), (-0.2291±0.0219), (-0.4637±0.0826), (1.7958±0.1502), (-0.1445±0.0239) dan (0.7492±0.0492).KEYWORDS: Bangladesh; coefficient; correlation; radiation; solar
Performance Analysis of Solar Combined Ejector-Vapor Compression Cycle Using Environmental Friendly Refrigerants
Authors: Kasaeian A. B. , Daviran S.
Published: October 2018

In this study, a new model of a solar combined ejector-vapor compression refrigeration system has been considered. The system is equipped with an internal heat exchanger to enhance the performance of the cycle. The effects of working fluid and operating conditions on the system performance including COP, entrainment ratio (Ï‰), compression ratio (rp) and exergy efficiency were investigated. Some working fluids suggested are: R114, R141b, R123, R245fa, R600a, R365mfc, R1234ze(e) and R1234ze(z). The results show that R114 and R1234ze(e) yield the highest COP and exergy efficiency followed by R123, R245fa, R365mfc, R141b, R152a and R600a. It is noticed that the COP value of the new solar ejector-vapor compression refrigeration cycle is higher than that of the conventional ejector cycle with R1234ze(e) for all operating conditions. This paper also demonstrates that R1234ze(e) will be a suitable refrigerant in the solar combined ejector-vapor compression refrigeration system, due to its environmental friendly properties and better performance.Â ABSTRAK: Kajian ini menganalisa model baru sistem penyejukan mampatan gabungan ejektor-wap solar.Sistem ini dilengkapi dengan penukar haba dalaman untuk meningkatkan prestasi kitaran.Kesan bendalir bekerja dan keadaan operasi pada prestasi sistem termasuk COP, nisbah pemerangkapan (Ï‰), nisbah mampatan (rp) dan kecekapan eksergi telah disiasat.Beberapa bendalir bekerja yang dicadangkan adalah: R114, R141b, R123, R245fa, R600a, R365mfc, R1234ze(e) dan R1234ze(z).Hasil kajian menunjukkan R114 dan R1234ze(e) menghasilkan COP dan kecekapan eksergi tertinggi diikuti oleh R123, R245fa, R365mfc, R141b, R152a dan R600a.Didapati nilai COP kitaran penyejukan mampatan bagi ejektor-wap solar baru adalah lebih tinggi daripada kitaran ejektor konvensional dengan R1234ze(e) bagi semua keadaan operasi.Kertas kerja ini juga menunjukkan bahawa R1234ze(e) boleh menjadi penyejuk yang sesuai dalam sistem penyejukan mampatan gabungan ejektor -wap solar, kerana ianya mempunyai prestasi yang lebih baik serta sifatnya yang lebih mesra alam sekitar.Â KEYWORDS: environmental friendly refrigerants; solar combined ejector-vapor compression cycle; R1234ze(e)
THE IMPACT OF THE PRODUCTION OF NEIGHBOUR WELLS ON WELL PRODUCTIVITY IN A SHALE GAS RESERVOIR
Authors: Nugrahanti Asri , Guntoro Agus , Fathaddin Muhammad Taufiq , Djohor Denny Suwanda
Published: October 2018

ABSTRACT: A shale gas reservoir is a self-contained source-reservoir system, characterized by extremely low matrix-permeability and low porosity, which typically requires extensive fracturing to produce gas at commercial rates. This paper presents a simulation experiment, intended to study the impact of well interference on gas recovery in a shale gas reservoir. The simulation model was constructed to study well interference through variation of horizontal well length, fracture half length, number of fracture, and well spacing. The results show that the increment of recovery factor of a well in the presence of neighbour wells is up to 7%. In this study, fracture half length is the most influence parameter on recovery factor, initial rate and reservoir pressure decline. ABSTRAK: Takungan gas syal merupakan sistem sumber-takungan kandung sendiri, khasnya kerana ia mempunyai kebolehtelapan-matriks yang begitu rendah dan keliangan yang rendah.Â  Sifat sebegini memerlukan ia melalui peretakan yang ekstensif untuk menghasilkan gas pada nilai komersial. Kertas kerja ini membentangkan eksperimen simulasi yang bertujuan untuk mengkaji impak perigi interferens terhadap perolehan gas dalam takungan gas syal.Â  Model simulasi di konstruksi untuk mengkaji interferens perigi; iaitu menerusi pelbagai variasiÂ  panjang mendatar perigi, retakan separuh panjang dan jarak perigi.Â  Keputusan menunjukkan peningkatan faktor perolehan perigi sebanyak 7% dengan kehadiran perigi bersebelahan. Dalam kajian ini, retakan separuh panjang merupakan ciri utama dalam faktor perolehan, kadar awalan dan penurunan tekanan takungan.
WHERE DID GENERAL MOTORS GO WRONG WITH THE IGNITION SWITCH RECALL?
Authors: Shaout Adnan , Dusute Cassandra
Published: October 2018

ABSTRACT: When it comes to purchasing a new car, a buyer expects the car to be safe and reliable. It is the responsibility of the automaker to ensure that those expectations are met. However, to err is human; recalls are a necessary part of life. When a recall happens, it then becomes the responsibility of the automaker to issue the recall in a timely manner. However, that was not the case with the General Motors (GM) ignition switch recall. The focus of this paper will be on the GM ignition switch, including sections regardingÂ the problem with the switch, who may have been responsible for approving the switch, and possible suggestions on how GM could have prevented the recall. ABSTRAK: Ketika keputusan diambil untuk membeli kereta baru, pembeli mahukan kereta yang selamat dan berwibawa. Adalah menjadi kewajipan pembuat kereta tersebut untuk memastikan bahawa harapan tersebut tercapai.Â  Namun, kita hanyalah manusia; penarikan balik menjadi kemestian. Apabila berlakunya perihal menarik balik produk, ianya adalah tanggungjawab pembuat kereta untuk menariknya dengan cara yang sepatutnya.Â  Namun dalam kes tarik balik suis pencucuh General Motors (GM) ini tidak berlaku. Kertas kerja ini akan memfokuskan kepada suis pencucuh GM; termasuklah masalah suis, pihak yang bertanggungjawab meluluskannya dan beberapa cadangan bagaimana sepatutnya GM boleh menghalang isu penarikan balik ini.KEYWORDS: approval process; validation plan; performance testing; ignition switch; embedded system; torque requirements; automotive recalls; industry
AEROELASTIC FLUTTER ANALYSIS OF SUPERSONIC WING WITH MULTIPLE EXTERNAL STORES
Authors: Azam Nur , Sulaeman Erwin
Published: October 2018

ABSTRACT: Flutter may be considered to be one of the most dangerous aeroelastic failure phenomenon. The flutter characteristic differs for each aircraft type, and depends on the wing geometry as well as its operational region of subsonic, transonic or supersonic speeds. Prior to performing a flight flutter test, extensive numerical simulations and Ground Vibration Test should be conducted where the structural finite element modes and the experimentation results should be matched, otherwise the numerical simulation model must be rejected. In this paper, the analysis of simulation of a supersonic wing equipped with external missiles loaded on the wing is presented. The structural mode shapes at each generated frequency are also visually presented. The analysis is carried out using MSC Nastran FEM software. The wing flutter with the external stores was simulated at different altitudes. The result shows that the flutter velocity is sensitive to the flight altitude. For this reason, the flutter analysis is conducted also for a negative altitude. The negative altitude is obtained by considering the constant equivalent speed-Mach number rule at the flutter speed boundary as a requirement in standard regulation of transport aircraft. ABSTRAK: Salah satu fenomena kegagalan aeroelastik yang paling membahayakan adalah kipasan (flutter). Ciri-ciri kegagalan kipasan (flutter) adalah berbeza untuk setiap jenis pesawat bergantung pada geometri sayap dan regim operasi sama ada subsonik, transonik atau supersonik. Sebelum melakukan ujian penerbangan kipasan , simulasi berangka luas dan ujian getaran peringkat bawahan (darat) perlu dijalankan di mana struktur mod unsur terhingga dan keputusan eksperimen harus dipadankan, sebaliknya model simulasi berangka boleh ditolak. Dalam kertas kerja ini, simulasi sayap supersonik dilengkapi dengan beban luaran peluru berpandu di sayap telah dianalisis di daerah supersonik tinggi. Bentuk mod struktur pada setiap mod frekuensi yang dihasilkan juga dipersembahkan secara visual. Analisis ini dilakukan dengan menggunakan perisian â€œFEMâ€ MSC Nastran. Kepakan sayap dengan kedai-kedai luar telah disimulasikan pada ketinggian yang berbeza. Hasil kajian menunjukkan bahawa halaju kipasan(flutter) sensitif terhadap ketinggian penerbangan. Atas sebab ini, analisis flutter dilakukan juga untuk ketinggian negatif. Ketinggian negatif diperoleh dengan mempertimbangkan tetap bersamaan kelajuan Mach beberapa peraturan pada kelajuan sempadan debar sebagai keperluan dalam peraturan piawaiaan pesawat pengangkutan.KEYWORDS: aeroelasticity; flutter; finite element method; external store; mode shape; supersonic wing
STUDIES ON THE EFFECT OF ARTIFICIAL AGEING HARDNESS ON TENSILE PROPERTIES AND IMPACT STRENGTH OF AL-6SI-0.5MG-2NI ALLOY
Authors: Hossain Abul , Kurny Abu Syedwais
Published: October 2018

The effect of different scheduled artificial ageing hardness on the tensile and impact properties of Al-6Si-0.5Mg-2Ni alloy was studied. The solution treated Al-6Si-0.5Mg-2Ni alloy was aged isochronally for 1 hour at temperatures up to 300oC. The precipitation stages during ageing were monitored by hardness measurements. Tensile and impact properties were determined by standard tests. During artificial ageing, the yield and ultimate tensile strength were found to increase with ageing hardness; the maximum being attained at peak hardness. Ductility and impact toughness of the alloy, on the other hand decreased with ageing hardness, reaching the minimum at the highest hardness. The strength of Al- 6Si-0.5Mg-2Ni alloy was best at highest hardness but exhibits poor ductility and impact strength.Â KEYWORDS: Al-6Si-0.5Mg-2Ni alloy; ageing; hardness; tensile properties; impact strength;
NORMALIZATION OF WAVE FUNCTION OF THE BAND STATES
Authors: Okhunov Abdurahim A. , Mamathonova Gulbadanbegim Sh. , Hassan Torla Hj. , Alam Mohammad Jahangir , Ismoilov Mukhtorjon X
Published: October 2018

Low â€“ lying band states are one of the most fundamental excitation modes in the energy spectra of deformed nuclei. Present paper a theoretically analysis the properties of deformed nucley within the phenomenological model (Usmanov 2010). The normalization of the wave functions of low â€“ lying excited band states are calculated.
HARMONIC COMPONENTS ESTIMATION IN POWER SYSTEM USING BACTERIAL FORAGING OPTIMIZATION ALGORITHM AND STOCHASTIC GRADIENT ALGORITHM WITH VARIABLE FORGETTING FACTOR
Authors: Mohammadzadeh Ahmad , Sadati Jalil , Rezaie Behrooz
Published: October 2018

In this paper, a hybrid configuration algorithm called stochastic gradient method with variable forgetting factor (SGVFF) is proposed to better estimate unknown parameters in a power system such as amplitude and phase of harmonics using variable forgetting factor following the bacterial foraging optimization algorithm (BFO). It must be mentioned that harmonic estimation is a nonlinear problem and using linear optimization algorithms for solving this problem reduces the convergence speed. Thus, BFO algorithm is used for initial estimation. In this paper, first, using little information and by applying BFO algorithm in an off-line procedure initial value for SGVFF algorithm is achieved and then SGVFF algorithm is gained in an on-line procedure. In the hybrid algorithm applied in this paper, amplitudes and phases are estimated simultaneously. Simulation results indicate that the proposed method has faster convergence speed, better performance and higher accuracy in a noisy system in comparison with recursive least squares variable forgetting factors algorithm (RLSVFF). This proves the superiority of the proposed method.KEYWORDS:Â  Power system harmonic; BFO algorithm; SGVFF method; RLSVFF method
INTELLIGENT FRACTIONAL ORDER ITERATIVE LEARNING CONTROL USING FEEDBACK LINEARIZATION FOR A SINGLE-LINK ROBOT
Authors: Ghasemi Iman , Ranjbar Noei Abolfazl , Sadati Jalil
Published: October 2018

In this paper, iterative learning control (ILC) is combined with an optimal fractional order derivative (BBO-Da-type ILC) and optimal fractional and proportional-derivative (BBO-PDa-type ILC). In the update law of Arimoto's derivative iterative learning control, a first order derivative of tracking error signal is used. In the proposed method, fractional order derivative of the error signal is stated in term of 'sa' where Â to update iterative learning control law. Two types of fractional order iterative learning control namely PDa-type ILC and Da-type ILC are gained for different value of a. In order to improve the performance of closed-loop control system, coefficients of both Â and Â learning law i.e. proportional , derivative Â and Â are optimized using Biogeography-Based optimization algorithm (BBO). Outcome of the simulation results are compared with those of the conventional fractional order iterative learning control to verify effectiveness of BBO-Da-type ILC and BBO-PDa-type ILC
RADIATION PERFORMANCE OF GAN AND INAS/GAAS QUANTUM DOT BASED DEVICES SUBJECTED TO NEUTRON RADIATION
Authors: Ahmad Fauzi Dhiyauddin , Alang Md Rashid Nahrul Khair , Mohamed Zin Muhammad Rawi , Hasbullah Nurul Fadzlin
Published: October 2018

In addition to their useful optoelectronics functions, gallium nitride (GaN) and quantum dots (QDs) based structures are also known for their radiation hardness properties. With demands on such semiconductor material structures, it is important to investigate the differences in reliability and radiation hardness properties of these two devices. For this purpose, three sets of GaN light-emitting diode (LED) and InAs/GaAs dot-in-a well (DWELL) samples were irradiated with thermal neutron of fluence ranging from 3Ã—1013 to 6Ã—1014 neutron/cm2 in PUSPATI TRIGA research reactor. The radiation performances for each device were evaluated based on the current-voltage (I-V) and capacitance-voltage (C-V) electrical characterisation method. Results suggested that the GaN based sample is less susceptible to electrical changes due to the thermal neutron radiation effects compared to the QD based sample.
NATURAL CONVECTIVE HEAT TRANSFER IN A POROUS MEDIUM WITHIN A TWO DIMENSIONAL ENCLOSURE
Authors: Ahmadi Mehdi
Published: October 2018

In this paper, to achievement the effect of increase number of heating components arrangement on the rate of heat transfer of natural convection, that others have been less noticed. Therefore, in each stage increase the number of heating components so much the space occupied by them remains constant. Then by calculating the amount of heat transfer in different Rayleigh number became clear that minify and distributing heating solid phase in the enclosure increases the total Nusselt number and heat transfer, One reason could be high intensity of fluid motion in corners and near walls of the enclosure. In the next section with the solid phases on the enclosure can be made porous media model. As the results showed an increase in average Rayleigh number, Nusselt number has increased. Also be seen in the lower Darcy numbers, speed of increase in Nusselt number with increase in average Rayleigh number is higher. It can be said that in enclosure by any number of solid pieces with certain Darcy number, with an increase in average Rayleigh number, circular flow inside the enclosure becomes more intense and isothermal lines near walls with constant temperature are so dense, that represents an increase in rate of heat transfer. Also by increasing the Darcy number, rate of heat transfer from the porous media has decreased, as regards that a large share of heat transfer in porous media is done by conduction, although increasing Darcy number increases heat transfer of natural convection but decrease a heat transfer of conduction, therefore decrease total of heat transfer.
Anti-lipolytic activity and phytochemical screening ofChelianthesalbomarginataagainst pathogenic microorganisms
Authors: Jarial Rini
Published: October 2018

ABSTRACT:The aim of the present study was to evaluate the therapeutic properties of selected fern, Chelianthusalbomarginataand to identify its functional compounds. The methanolic fern-extract (MFE) of these ferns was assessed for anti-bacterial activities by measuring inhibition zones against a panel of pathogenic bacterial strains using agar diffusion method. MFE at a concentration of 25 Î¼g/ml showed marked anti-bacterial activity against all bacterial strains (6-23mm zone of inhibition) and was maximum against Enterobacter sp (23 mm). In addition, the MFE of C. albomarginatahad the best MIC values of 2.25Âµg/ml against S. aureus and Enterobacter sp., respectively. The MFE also possessed good anti-lipolytic activity (66.5%) against a porcine pancreatic lipase (PPL) and cholesterol oxidase inhibition (79%). This result showed that MFE of C. albomarginataunder optimal concentrationis not only a potent source of natural anti-oxidants and anti-bacterial activity but also possesses efficient cholesterol degradation and anti-lipolytic activities, that is to be beneficial in the body weight management.
A Proposed Method for Improving the Performance of P-Type GaAs IMPATTs
Authors: A. El-Motaafy H.
Published: October 2018

A special waveform is proposed and assumed to be the optimum waveform for p-type GaAs IMPATTs. This waveform is deduced after careful and extensive study of the performance of these devices. The results presented here indicate the superiority of the performance of the IMPATTs driven by the proposed waveform over that obtained when the same IMPATTs are driven by the conventional sinusoidal waveform. These results are obtained using a full-scale computer simulation program that takes fully into account all the physical effects pertinent to IMPATT operation.  In this paper, it is indicated that the superiority of the proposed waveform is attributed to its ability to reduce the bad effects that usually degrade the IMPATT performance such as the space-charge effect and the drift-velocity dropping below saturation effect. The superiority is also attributed to the ability of the proposed waveform to improve the phase relationship between the terminal voltage and the induced current.Key Words: Computer-Aided Design, GaAs IMPATT, Microwave Engineering
High Speed Submarine Optical Fiber Communication System:Pressure and Temperature Effects
Authors: Mohammed A. A.
Published: October 2018

In the present paper, the performance of high speed submarine optical fiber cable systems is investigated, taking into account both the pressure and the temperature effects. Both the pressure and the temperature are depth-dependent variables, while both the spectral losses and the dispersion effects are temperature as well as wavelength dependent variables. Two important cases with real fibers are processed: a case with dispersion cancellation and a case without dispersion cancellation. It is found that the ocean pressure (due to the depth) shifts the dispersion-free wavelength towards the third communication window. In general, as the depth increases the maximum transmitted bit rate increases in the range of interest. The system capacity as well as the spectral losses, and the dispersion effects are parametrically investigated over wide-range ranges of the set of affecting parameters {wavelength, ocean depth (and consequently the ocean pressure and temperature), and the chemical structure}. Key Words: Submarine Optical Fiber, Undersea Optical Communication, Pressure and Temperature Effects, Transoceanic Optical Communications
Catalytic Cracking of Palm Oil Over Zeolite Catalysts: Statistical Approach
Authors: S. Bhatia F. A. A. Twaiq and , M. Zabidi N. A.
Published: October 2018

The catalytic cracking of palm oil was conducted in a fixed bed micro-reactor over HZSM-5, zeolite ? and ultrastable Y (USY) zeolite catalysts. The objective of the present investigation was to study the effect of cracking reaction variables such as temperature, weight hourly space velocity, catalyst pore size and type of palm oil feed of different molecular weight on the conversion, yield of hydrocarbons in gasoline boiling range and BTX aromatics in the organic liquid product.  Statistical Design of Experiment (DOE) with 24 full factorial design was used in experimentation at the first stage.  The nonlinear model and Response Surface Methodology (RSM) were utilized in the second stage of experimentation to obtain the optimum values of the variables for maximum yields of hydrocarbons in gasoline boiling range and aromatics.  The HZSM-5 showed the best performance amongst the three catalysts tested.  At 623 K and WHSV of 1 h-1, the highest experimental yields of gasoline and aromatics were 28.3 wt.% and 27 wt.%, respectively over the HZSM-5 catalyst.  For the same catalyst, the statistical model predicted that the optimum yield of gasoline was 28.1 wt.% at WHSV of 1.75 h-1 and 623 K.  The predicted optimum yield of gasoline was 25.5 wt.% at 623 K and WHSV of 1 h-1.KEY WORDS: Catalytic Cracking, Palm Oil, Zeolite, Design Of Experiment, Response Surface Methodology.
Free Vibration of Variable Thickness Plates Using Characteristic Orthogonal Polynomial Strip Functions Subjected To Different Combinations of Boundary Conditions
Authors: A. S. Ashour A. A. Rizk and
Published: October 2018

A set of characteristic orthogonal polynomial strip functions was used to study the flexural vibration of variable thickness plates in one direction. The starting function in the set, which is satisfying the geometry and natural conditions, is developed from the solution of a static beam subjected to an arbitrary load that expanded into a Taylor series. The Gram-Schmidt orthogonalization process is used to generate the reminder functions of the set. The natural frequencies of the plat are calculated by using the finite strip method together with the transition matrix. Numerical results are obtained for different combination of boundary conditions, tapered ratio and aspect ratio. It is demonstrated that the method as well as the orthogonal strip functions yield good accuracy and fast convergence by comparisons with available results in the literature. This technique can also be used to solve some other complicated problems in the engineering applications.
Preparation of Active Absorbent for Flue Gas Desulfurization From Coal Bottom Ash: Effect of Absorbent Preparation Variables
Authors: Abdul Rahman Mohamed Chang Chin Li, Lee Keat Teong, Subhash Bhatia and
Published: October 2018

An active absorbent for flue gas desulfurization was prepared from coal bottom ash, calcium oxide (CaO) and calcium sulfate by hydro-thermal process. The absorbent was examined for its micro-structural properties. The experiments conducted were based on Design Of Experiments (DOE) according to 23 factorial design. The effect of various absorbent preparation variables such as ratio of CaO to bottom ash (A), hydration temperature (B) and hydration period (C) towards the BET (Brunauer-Emmett-Teller) specific surface area of the absorbent were studied. At a CaO to bottom ash ratio = 2, hydration temperature = 200 ?C and hydration period = 10 hrs, absorbent with a surface area of 90.1 m2/g was obtained. Based on the analysis of the factorial design, it was concluded that factor A and C as well as the interaction of factors ABC and BC are the significant factors that effect the BET surface area of the absorbent. A linear mathematical model that describes the relation between the independent variables and interaction between variables towards the BET specific surface area of the absorbent was also developed. Analysis of variance (ANOVA) showed that the model was significant at 1% level.Key Words: Absorbent, Bottom Ash, Design Of Experiments, Desulfurization, Surface Area.
A New Fast Approximate Hilbert Transform with Different Applications
Authors: Hossen Abdulnasir
Published: October 2018

A new and fast approximate Hilbert transform based on subband decomposition is presented. This new algorithm is called the subband (SB)-Hilbert transform.  The reduction in complexity is obtained for narrow-band signal applications by considering only the band of most energy.  Different properties of the SB-Hilbert transform are discussed with simulation examples.  The new algorithm is compared with the full band Hilbert transform in terms of complexity and accuracy. The aliasing errors taking place in the algorithm are found by applying the Hilbert transform to the inverse FFT (time signal) of the aliasing errors of the SB-FFT of the input signal.  Different examples are given to find the analytic signal using SB-Hilbert transform with a varying number of subbands.  Applications of the new algorithm are given in single-sideband amplitude modulation and in demodulating frequency-modulated signals in communication systems.Key Words:  Fast Algorithms, Hilbert Transform, Analytic Signal Processing.
Problems in Biotechnology Research
Authors: Hamzah M. Salleh Parveen Jamal and
Published: October 2018

To meet the challenges posed by the growing population of the world, biotechnology research is being pursued in all countries. In the area of medicine remarkable success has been achieved. It is believed that in future this trend will continue. In the area food also scientists and technocrats have shown considerable success, but in this area they have not received appreciation because of many objections. The paper discusses issues pertaining to biotechnology researches, because if these issues are not thoroughly discussed and problems are not hammered out, biotechnology researches will go on but will fail to serve the humanity.Key Words: biodiversity, biotechnology, cloning, germ cell, genetic materials, biosafety.
Book Review: Materials Science aAnd Engineering: An Introduction by William D. Callister
Authors: Malik Hassan
Published: October 2018

For a number of decades, Materials Science and Engineering an Introduction, has been an essential and trusted source of literature, as an introduction to Materials Science and Engineering. Now revised and updated the sixth edition is now available.
Experimental and Numerical Analysis of Electronics Heat Sink
Authors: Yousif A. Abakr Ahmad F. Ismail, Mirghani I. Ahmed, and
Published: October 2018

Cooling of electronic components continues to attract many research and development activities towards achieving an effective way of cooling. Computational fluid dynamics (CFD) tools may be considered as a cheap substitute for expensive experimental testing methods. In this work the cooling of a simulated electronic board was modeled using FLUENTTM CFD software, and experimental procedures were followed to validate the estimated results, and to understand the factors that would affect the software capability to predict the actual measured values. Results showed good agreement between the simulation and experimental results. The software was found to be capable to predict the exact values at the locations where the temperature values were similar to the board mean temperature. The maximum percentage error was found to be limited to 4.7%, and the capability of the software to estimate the exact measured values was found to be affected by the function of thermal wake generation.

Keywords: CFD, Electronic cooling, Heat sink, Simulation