Universiti Teknologi Malaysia Institutional Repository: No conditions. Results ordered -Date Deposited. 2023-09-29T04:32:18ZEPrintshttp://eprints.utm.my/images/sitelogo.gifhttp://eprints.utm.my/id/eprint/2017-09-25T07:26:16Z2017-09-25T07:26:16Zhttp://eprints.utm.my/id/eprint/id/eprint/22262This item is in the repository with the URL: http://eprints.utm.my/id/eprint/id/eprint/222622017-09-25T07:26:16ZThe optical characterization of hydrogenated amorphous carbon thin films deposited by a DC-PECVD methodDiamond-like carbon (DLC) is a metastable form of amorphous carbon with attractive properties such as high hardness, low friction, chemical inertness and high wear resistance.Samsudi Sakrani2014-11-02T03:13:23Z2020-09-15T00:20:33Zhttp://eprints.utm.my/id/eprint/id/eprint/42623This item is in the repository with the URL: http://eprints.utm.my/id/eprint/id/eprint/426232014-11-02T03:13:23ZComparison of the performance of the extreme value type 1 (EV1) and the rayleigh distributionSiti Roslindar Yaziz2014-11-02T03:13:23Z2017-10-04T04:23:04Zhttp://eprints.utm.my/id/eprint/id/eprint/42644This item is in the repository with the URL: http://eprints.utm.my/id/eprint/id/eprint/426442014-11-02T03:13:23ZDiscrete event simulation for telephone channel assignment problem Chew Lan Yeoh2014-11-02T03:13:20Z2017-10-04T02:58:47Zhttp://eprints.utm.my/id/eprint/id/eprint/42640This item is in the repository with the URL: http://eprints.utm.my/id/eprint/id/eprint/426402014-11-02T03:13:20ZDevelopment of C-scan control system for ultrasonic flaw mapping Thoo Chee Loong Soo2014-11-02T03:13:18Z2017-10-05T04:33:48Zhttp://eprints.utm.my/id/eprint/id/eprint/42653This item is in the repository with the URL: http://eprints.utm.my/id/eprint/id/eprint/426532014-11-02T03:13:18ZGrowth optimization studies of amylomyces rouxii and the cloning and expression of glucoamylase cDNA in E. coli Hasniza Ramli2014-11-02T03:13:18Z2017-10-06T07:04:05Zhttp://eprints.utm.my/id/eprint/id/eprint/42689This item is in the repository with the URL: http://eprints.utm.my/id/eprint/id/eprint/426892014-11-02T03:13:18ZNew numerical methods for solving second order initial value problems with periodic solution Chang Phang 2014-11-02T03:13:17Z2017-09-27T13:19:24Zhttp://eprints.utm.my/id/eprint/id/eprint/42595This item is in the repository with the URL: http://eprints.utm.my/id/eprint/id/eprint/425952014-11-02T03:13:17ZA study of finite depth fluid equation Fuaada Mohd. Siam2014-11-02T03:13:17Z2017-08-30T00:54:08Zhttp://eprints.utm.my/id/eprint/id/eprint/42773This item is in the repository with the URL: http://eprints.utm.my/id/eprint/id/eprint/427732014-11-02T03:13:17ZSynthesis and characterisation of modified mesoporous MCM-41 for the dibenzoylation of biphenyl Rino Rakhmata Mukti2014-11-02T03:13:16Z2017-08-30T00:55:03Zhttp://eprints.utm.my/id/eprint/id/eprint/42774This item is in the repository with the URL: http://eprints.utm.my/id/eprint/id/eprint/427742014-11-02T03:13:16ZTaburan normal multivariat dan T2 hotelling Noraslinda Mohamed Ismail2014-11-02T03:13:15Z2017-10-02T02:48:00Zhttp://eprints.utm.my/id/eprint/id/eprint/42597This item is in the repository with the URL: http://eprints.utm.my/id/eprint/id/eprint/425972014-11-02T03:13:15ZAdunan polistirena/getah stirena butadiena terisi serbuk sekam padi Zurina Mohamad2014-11-02T03:13:15Z2017-08-30T01:17:10Zhttp://eprints.utm.my/id/eprint/id/eprint/42778This item is in the repository with the URL: http://eprints.utm.my/id/eprint/id/eprint/427782014-11-02T03:13:15ZThe development of manganese oxide based catalyst materials ageing for emission control : synthesis, catalytic activity and characterization Alina Rahayu Mohamed2014-11-02T03:13:12Z2017-10-04T04:26:21Zhttp://eprints.utm.my/id/eprint/id/eprint/42646This item is in the repository with the URL: http://eprints.utm.my/id/eprint/id/eprint/426462014-11-02T03:13:12ZElectrical and thermal properties of conductive polypyrrole and its composites Kwong Seng Lee2014-11-02T03:13:10Z2017-10-07T00:54:38Zhttp://eprints.utm.my/id/eprint/id/eprint/42705This item is in the repository with the URL: http://eprints.utm.my/id/eprint/id/eprint/427052014-11-02T03:13:10ZPencirian saput tebal SnO2 dihasilkan melalui kaedah cetakan skrin Nadira Kamarudin2014-11-02T03:13:10Z2020-09-27T05:53:36Zhttp://eprints.utm.my/id/eprint/id/eprint/42726This item is in the repository with the URL: http://eprints.utm.my/id/eprint/id/eprint/427262014-11-02T03:13:10ZPlacement and routing in VLSI design problem using single row routing techniqueFarhana Johar2014-11-02T03:13:10Z2014-11-02T03:13:10Zhttp://eprints.utm.my/id/eprint/id/eprint/42747This item is in the repository with the URL: http://eprints.utm.my/id/eprint/id/eprint/427472014-11-02T03:13:10ZRiemann mapping function : some theories and construction Syahirbanun Isa2014-11-02T03:13:07Z2017-08-20T03:19:05Zhttp://eprints.utm.my/id/eprint/id/eprint/42749This item is in the repository with the URL: http://eprints.utm.my/id/eprint/id/eprint/427492014-11-02T03:13:07ZSinThesis dan pencirian bahan penjerap oktadekilsilil silika dalam penggunaan pengerakan fasa pepejal Norliza Dzakaria2014-09-15T04:49:38Z2017-09-25T07:27:36Zhttp://eprints.utm.my/id/eprint/id/eprint/22538This item is in the repository with the URL: http://eprints.utm.my/id/eprint/id/eprint/225382014-09-15T04:49:38ZInfrared analysis of a-C:H thin films grown by DC-PECVD at various chamber pressuresInfrared spectroscopy (IR spectroscopy or vibrational spectroscopy) involves the interaction of infrared radiation with matter. It covers a range of techniques, mostly based on absorption spectroscopy. As with all spectroscopic techniques, it can be used to identify and study chemicals.Samsudi SakraniSuriani Abu BakarBakar IsmailPutut Marwoto2014-09-04T03:42:10Z2017-09-25T06:31:03Zhttp://eprints.utm.my/id/eprint/id/eprint/22181This item is in the repository with the URL: http://eprints.utm.my/id/eprint/id/eprint/221812014-09-04T03:42:10ZAnalytical and numerical methods for the riemann problemThe Riemann problem is very useful for the understanding of equations like Euler conservation equations because all properties, such as shocks and rarefaction waves, appear as characteristics in the solution. It also gives an exact solution to some complex nonlinear equations, such as the Euler equations.Mohamed M. S. NasserAli Hassan Mohamed Murid2014-04-22T04:05:38Z2017-09-25T06:34:22Zhttp://eprints.utm.my/id/eprint/id/eprint/22180This item is in the repository with the URL: http://eprints.utm.my/id/eprint/id/eprint/221802014-04-22T04:05:38ZA boundary integral equation related to the riemann map and the riemann problemThe Riemann problem is very useful for the understanding of equations like Euler conservation equations because all properties, such as shocks and rarefaction waves, appear as characteristics in the solution. It also gives an exact solution to some complex nonlinear equations, such as the Euler equations.Mohamed M. S. NasserAli Hassan Mohamed Murid2014-04-22T04:02:37Z2017-09-25T06:35:33Zhttp://eprints.utm.my/id/eprint/id/eprint/22182This item is in the repository with the URL: http://eprints.utm.my/id/eprint/id/eprint/221822014-04-22T04:02:37ZThe numerical evaluation of the hilbert transform on smooth Jordan curves using a freedholm integral equationIn mathematics and in signal processing, the Hilbert transform is a linear operator that takes a function, u(t) of a real variable and produces another function of a real variable H(u)(t). The Hilbert transform is important in signal processing, where it derives the analytic representation of a signal u(t).Mohamed M. S. NasserAli Hassan Mohamed Murid2013-04-09T01:21:39Z2017-09-27T03:20:20Zhttp://eprints.utm.my/id/eprint/id/eprint/29936This item is in the repository with the URL: http://eprints.utm.my/id/eprint/id/eprint/299362013-04-09T01:21:39ZPersamaan terbitan lanjutanBuku ini ditulis bagi rujukan lanjutan pelajar peringkat Ijazah Sarjana Muda Sains dengan pengkhususan dalam matematik di institusi pengajian tinggi tempatan. Namun buku ini boleh juga digunakan oleh pelajar kejuruteraan yang telah mengambil mata pelajaran persamaan terbitan dan ingin memahami lebih lanjut pengetahuan tentang persamaan terbitan. Persamaan Legendre dan Persamaan Bessel yang begitu meluas digunakan dalam bidang kejuruteraan telah dibincangkan dengan mendalam. Keputusan penting dinyatakan sebagai lema dan teorem dan hampir semua lema dan teorem telah dibuktikan. Pembaca yang tidak memerlukan bukti bagi lema dan teorem boleh mengabaikannya dan terus meneliti contoh penggunaannya yang disertakan selepas setiap teorem berkenaan. Latihan yang mencukupi juga disediakan dalam setiap bahagian supaya pelajar boleh menguji kefahaman mereka. Jawapan bagi latihan yang bernombor ganjil disertakan bagi tujuan semakan.Yusof Yaacob2013-04-09T01:21:38Z2017-09-27T03:18:27Zhttp://eprints.utm.my/id/eprint/id/eprint/29935This item is in the repository with the URL: http://eprints.utm.my/id/eprint/id/eprint/299352013-04-09T01:21:38ZPengenalan sains forensikPengenalan Sains Forensik ditulis dengan tujuan untuk menarik minat pelajar terhadap bidang ini. Usaha pendokumenan ini selari dengan hasrat setiap pendidik sains forensik yang ingin melihat ilmu sains ini lebih mudah difahami dan dihargai oleh generasi masa kini. Sebahagian besar teks yang diketengahkan dalam buku ini menumpukan perbincangan kepada item bukti fizikal yang sering dijumpai di tempat kejadian jenayah. Setiap bab turut memasukkan teknik terkini analisis forensik, prosedur dan amalan pengumpulan serta penyimpanan bahan bukti. Implikasi profilan DNA dianggap penting dalam sains forensik, justeru kepentingannya dimasukkan sebagai salah satu bab dalam buku ini. Subjek DNA ditulis dengan cara yang mudah difahami oleh pembaca tanpa memerlukan latar belakang sains. Walaupun Pengenalan Sains Forensik terbit daripada kursus elektif Sains Forensik yang ditawarkan di Universiti Teknologi Malaysia, bahan subjek buku ini tidak terhad kepada pelajar universiti sahaja. Penyiasat tempat kejadian seperti pegawai polis, pegawai perubatan, ahli bomba, dan ahli kimia juga perlu memiliki pengetahuan berkenaan kaedah dan keupayaan sesebuah makmal forensik. Hanya dengan menggabungkan ilmu pengetahuan tentang prinsip dan kaedah analisis sains forensik dengan logik dan akal budi, penyiasat akan mendapat kefahaman yang lebih mendalam daripada aspek kepentingan bukti fizikal dan peranannya dalam siasatan jenayah. Sememangnya, sains forensik bermula di tempat kejadian jenayah. Jika penyiasat tidak dapat mengenal, mengutip dan membungkus bukti fizikal dengan betul, instrumen atau kepakaran yang sehebat manapun tidak dapat membantu menyelesaikan sesuatu kes jenayah. Di bahagian akhir kebanyakan bab, beberapa contoh kes dipersembahkan bagi menggambarkan aplikasi sains forensik dan betapa relevannya pengetahuan ini kepada dunia sebenar siasatan jenayah.Umi Kalthom AhmadAbdul Rahim Yacob2013-04-09T01:21:36Z2017-02-08T01:20:42Zhttp://eprints.utm.my/id/eprint/id/eprint/29934This item is in the repository with the URL: http://eprints.utm.my/id/eprint/id/eprint/299342013-04-09T01:21:36ZLASER: prinsip penjanaanSecara ringkas buku ini membincangkan prinsip dan penjanaan laser. Sifat-asas optik seperti serapan, pantulan serakan, biasan dan teori Einstein adalah dasar yang digunakan dalam penjanaan ini. Buku ini turut menjelaskan konsep suap balik dan pergandaan cahaya yang digunakan untuk mengamplifikasikan cahaya. Selain daripada itu, alat pertama yang mendemonstrasikan idea Einstein iaitu Maser turut dibincangkan. Penggunaan bahan tak linear dapat menjana laser harmonik dan jenis pensuisan yang berbeza-beza. Penggantian bahan laser sama ada pepejal, cecair dan gas akhirnya mewujudkan pelbagai jenis laser yang berlainan. Secara am, buku ini merangkumi semua aspek janaan laser dari peringkat awal penciptaan hingga ke tahap yang terkini. Kandungan buku ini dapat memberi jawapan kepada mereka yang ingin mengenali dan mengetahui apa itu laser dan bagaimana laser dapat dijanakan. Buku ini sesuai sebagai teks dan rujukan bagi peringkat pengajian tinggi dan sebagai bahan bacaan umum untuk menambah ilmu.Noriah Bidin2013-04-09T01:21:34Z2017-09-27T03:06:54Zhttp://eprints.utm.my/id/eprint/id/eprint/29933This item is in the repository with the URL: http://eprints.utm.my/id/eprint/id/eprint/299332013-04-09T01:21:34ZKembalinya dinar emas dan dirham Perak: mata wang umat IslamBuku Kembalinya Dinar Emas dan Dirham Perak: Mata Wang Umat Islam ini merupakan hasil kajian dan penglibatan pengarang dalam isu riba. Buku ini membicarakan usaha ke arah mengembalikan mata wang Dinar Emas dan Dirham Perak, mata wang umat Islam yang telah lenyap daripada masyarakat Islam sejak kejatuhan Khalifah Uthmaniyah Turki dalam tahun 1924. Menyentuh tentang isu yang dibangkitkan, buku ini memberikan penjelasan bagaimana mulanya wang emas digantikan dengan sistem wang janji dan seterusnya lahir sistem wang kertas dan perbankan yang ada sekarang. Beberapa masalah wang kertas turut dibincangkan, salah satunya adalah nilai wang kertas yang diberikan nilainya oleh pihak ketiga. Selanjutnya buku ini mengupas isu riba yang berkait rapat dengan sistem wang kertas, di mana pihak bank boleh menjana wang dengan mengenakan faedah dan sebagai ke atas si peminjam. Di samping itu, beberapa kesan riba seperti pengangguran, kerosakan alam sekitar dan peluang perniagaan juga disentuh. Usaha mengembalikan Dinar Emas dan Dirham Perak ini kini telah menjadi isu global, bagi menyelesaikan pembayaran perdagangan antarabangsa. Walaupun Dinar Emas dan Dirham Perak ini dicadangkan untuk kegunaan bagi perdagangan antarabangsa, mata wang ini juga boleh digunakan sebagai simpanan kerana emas mempunyai nilai intrinsik sebagai hantaran, mas kahwin, zakat, dan sebagainya.Zuhaimy Ismail2013-04-09T01:21:33Z2017-09-27T03:04:06Zhttp://eprints.utm.my/id/eprint/id/eprint/29932This item is in the repository with the URL: http://eprints.utm.my/id/eprint/id/eprint/299322013-04-09T01:21:33ZFizik modenBuku ini ditulis dengan tujuan untuk dijadikan buku teks dan rujukan bagi kursus Fizik Moden kepada pelajar yang mengikuti kursus fizik di peringkat Ijazah Sarjana Muda di institut pengajian tinggi tempatan. Buku ini disediakan dan diolah dengan pendekatan yang mudah difahami dengan menggunakan kaedah matematik mudah dalam menerangkan sesuatu konsep. Setiap perbincangan disusuli dengan gambar rajah atau jadual yang berkaitan bagi memberikan penjelasan yang lebih jelas tentang sesuatu perkara yang dibincangkan. Soalan contoh dan penyelesaiannya serta latihan juga dikemukakan pada setiap tajuk bagi membolehkan pelajar memahami tajuk berkenaan dengan lebih mendalam lagi.Husin Wagiran2013-04-09T01:21:31Z2017-09-27T03:01:09Zhttp://eprints.utm.my/id/eprint/id/eprint/29931This item is in the repository with the URL: http://eprints.utm.my/id/eprint/id/eprint/299312013-04-09T01:21:31ZFizik asas untuk sains & kejuruteraan mekanik, sifat jirim dan habaBuku Fizik Asas untuk Sains dan Kejuruteraan: Mekanik, Sifat Jirim dan Haba ini ditulis sebagai buku rujukan bagi mata pelajaran fizik peringkat pra–universiti dan diploma. Buku ini menekankan konsep dan prinsip fizik yang menjadi asas kepada pemahaman fizik dalam pengajian sains dan kejuruteraan peringkat tinggi.Husin WagiranMd. Rahim SaharMohd. Mustamam Abd. Karim2012-11-16T08:40:05Z2012-11-16T08:53:26Zhttp://eprints.utm.my/id/eprint/id/eprint/427This item is in the repository with the URL: http://eprints.utm.my/id/eprint/id/eprint/4272012-11-16T08:40:05ZSynthesis of ZSM-5 type zeolite using crystalline silica of rice husk ashZainab RamliHasliza Bahruji2011-07-29T01:37:27Z2017-09-20T07:18:45Zhttp://eprints.utm.my/id/eprint/id/eprint/13269This item is in the repository with the URL: http://eprints.utm.my/id/eprint/id/eprint/132692011-07-29T01:37:27ZInverse modelling of the mass transfer process in the RDC column by fuzzy approachInverse modeling is natural in many real worl
d application including industrial chemical
engineering problems. This paper describes the process
of determines optimal input and output of number
of drops in various stage of rotating disc contactor column using fuzzy model. An algorithm of the fuzzy
model is developed to simulate the above process.Normah MaanJamalludin Abdul TalibHafez Elfakie2010-11-19T02:33:05Z2010-11-19T02:33:05Zhttp://eprints.utm.my/id/eprint/id/eprint/11005This item is in the repository with the URL: http://eprints.utm.my/id/eprint/id/eprint/110052010-11-19T02:33:05ZStudy of Nd203-CuO-P205 glass system by elastic propertiesLongitudinal and shear ultrasonic velocities were measured in different compositions of the glass system Nd203(x)CuO(35-x)P205(65) at temperature range between 270 K and 323 K. From the transit time data and density, we found that all the elastic properties for these glasses decrease as the Nd203 content increase, which indicates a weakening ofthe binding energy in the network.Agus Setyo BudiRosli RussinMd. Rahim Sahar2010-11-19T02:32:45Z2010-11-19T02:32:45Zhttp://eprints.utm.my/id/eprint/id/eprint/11004This item is in the repository with the URL: http://eprints.utm.my/id/eprint/id/eprint/110042010-11-19T02:32:45ZCorrelation between objective and subjective image quality measures of medical radiographsImage quality of Lanex Regular/T Mat G and Lanex Regular/T Mat L screen-film systems was measured objectively by means of noise equivalent quanta (NEQ) and subjectively by means of receiver operating characteristic (ROC) curve analysis to study the correlation between the two measures. For the objective measure, uniformly exposed radiographs and radiographs of bar pattern test object were used to determine the NEQ. For the subjeclive measure, detection of simulated lesions in posteroanterior anthropomorphic chest radiographs by an observer was analysed by the ROC methodology. Both measures show that a low frequency signal shows better on Lanex Regular/T Mat L, whilst a high frequency signal shows better on Lanex Regular/T Mat G.Wan Muhamad Saridan Wan HassanYusof MunajatShamsul Sahibuddin2010-11-19T02:31:53Z2010-11-19T02:31:53Zhttp://eprints.utm.my/id/eprint/id/eprint/10997This item is in the repository with the URL: http://eprints.utm.my/id/eprint/id/eprint/109972010-11-19T02:31:53ZDLTS and C(t) transient study of defects induced by neutron radiation in MOS structures of CCD technologyThe aim of this paper is to study neutron irradiation effects on PMOS capacitors and NMOSFETs transistors. The characterization of induced defects was made by capacitance transients C(t) measurements, DLTS spectroscopy, and optical DLTS (ODLTS). DLTS spectra present three peaks (1, 2, and 3) due to deep levels created in the semiconductor and two peaks (4 and 5) due to minority carrier generation. Levels 1 and 2 are reported in literature and it was suggested that the level 2 may be due to the divacancy. Two other minority carrier traps have been observed on ODLTS spectra after irradiation. This can explain the decrease of the minority carrier generation lifetime observed in capacitance transients measurements.Aziz AhaitoufHazri BakhtiarEtienne LossonJean-Pierre Charles2010-11-19T02:31:39Z2010-11-19T02:31:39Zhttp://eprints.utm.my/id/eprint/id/eprint/11003This item is in the repository with the URL: http://eprints.utm.my/id/eprint/id/eprint/110032010-11-19T02:31:39ZOptical properties of thin hexagonal boron nitride layersThin films of hexagonal boron nitride have been deposited at low temperature in a microwave plasma enhanced chemical vapor deposition reactor. They have been characterized by Infrared (FTIR) and micro-Raman spectroscopy (SMR). The films are optically anisotropic, and the IR measurements can be properly modelized when using an uniaxial model for the layers. This description is valid at the macroscopic scale, but gives only an averaged response of the polycrystalline nature of the films. Actually, they are constituted at the atomic scale by a collection of nanocrystallites with a preferred orientation around the normal of the layer. The size of the crystallites can be evaluated by micro-Raman measurements, when taking into account a confinement model. Some thermal annealing have been performed.Ali SoltaniHazri BakhtiarPhilippe TheveninArmand Bath2010-06-10T10:04:57Z2017-10-19T04:27:54Zhttp://eprints.utm.my/id/eprint/id/eprint/9891This item is in the repository with the URL: http://eprints.utm.my/id/eprint/id/eprint/98912010-06-10T10:04:57ZOn matlab finite element simulations of steady - state burger's equationBurger's equations have been used, time and again to model successfully many physical phenomena such as in shock waves, acoustic transmision, traffic flow, supersonic flow about aerofoils and wave propagations in thermoelastic medium. Via Cole-Hopf transformation, the equations are reduced to standard diffusion equations. With the advent of modem computer technology, numerical techniques are very much sought after. Two fundamental tenets of numerical methods are the methods of finite difference and the methods using finite elements. Both methods call for the solutions of large sparse matrices. In this paper, we shall present finite element simulations of the Burger's equations using MATLABRio Hirowati ShariffudinIthnin Abdul JalilKam Lai Hoy2009-05-13T03:10:33Z2010-06-11T04:40:38Zhttp://eprints.utm.my/id/eprint/id/eprint/8810This item is in the repository with the URL: http://eprints.utm.my/id/eprint/id/eprint/88102009-05-13T03:10:33ZNew nonlinear four-step method for y"=f(t,y)In this paper, a study is made on the possibility of developing a nonlinear four-step method based on contraharmonic mean. The study is done since the four-step methods always give higher order than popular methods like Numerov and classical Runge-Kutta methods. A detailed study of consistency, stability, convergence and interval of periodicity has been done to convince ourselves of using this new method. The numerical results shows that the method is more accurate than the existing one. Nazeeruddin YaacobChang Phang2009-05-13T02:57:02Z2010-08-13T01:57:16Zhttp://eprints.utm.my/id/eprint/id/eprint/8808This item is in the repository with the URL: http://eprints.utm.my/id/eprint/id/eprint/88082009-05-13T02:57:02ZPemodelan harga minyak sayuran menggunakan analisis regresi linear berganda.This study focused on application of multiple regression in modeling vegetable oil prices. Five vegetable oil prices, namely CPO, SBO, CNO, PKO, and RSO have been analysed using monthly oil price data from year 2000. We found that multiple linear regression gave the $R^2$ value of 0.887, meaning 88.7\% of variance in CPO price could be explained by RSO, PKO, and CNO. The $t$-test showed that the parameter estimates is significant at one percent level. This study concluded that multicollinearity and autocorrelation were detected inmuliple linear regression and are needed to be considered in further research. Azme KhamisZuhaimy IsmailAni Shabri2009-05-12T08:43:07Z2017-10-11T01:56:56Zhttp://eprints.utm.my/id/eprint/id/eprint/8801This item is in the repository with the URL: http://eprints.utm.my/id/eprint/id/eprint/88012009-05-12T08:43:07ZPembinaan homeomorfisma dari sfera ke elipsoid.In this paper, we present the construction of homeomorphism from unit sphere; $S^2$ to ellipsoid which is one unit in xy-axis and its poles are at $z=2$ and $z=-2$; $E^2$ through Riemann surface structures. Proving techniques by construction and contradiction are highlighted.
Li Yun LiauTahir Ahmad2009-01-14T00:33:24Z2017-08-13T08:09:13Zhttp://eprints.utm.my/id/eprint/id/eprint/7657This item is in the repository with the URL: http://eprints.utm.my/id/eprint/id/eprint/76572009-01-14T00:33:24ZInverse modeling of mass transferprocess in the RDC column by fuzzy approachInverse modeling is natural in many real world application including industrial chemical engineering problems. This paper describes the process of determines optimal input and output of number of drops in various stage of rotating disc contactor column using fuzzy model. An algorithm of the fuzzy model is developed to simulate the above process. Inverse model to determine the optimal number of drops of RDC column using fuzzy approach.Normah MaanJ. TalibK. A. ArshadT. Ahmad2009-01-09T08:34:20Z2009-01-09T08:34:20Zhttp://eprints.utm.my/id/eprint/id/eprint/7595This item is in the repository with the URL: http://eprints.utm.my/id/eprint/id/eprint/75952009-01-09T08:34:20ZStatistical prediction of terrestrial gamma radiation dose rate based on geological features and soil types in Kota Tinggi district, MalaysiaA statistical prediction of terrestrial gamma radiation dose rate has been performed, covering the Kota Tinggi district of Peninsular Malaysia. The prediction has been based on geological features and soil types. The purpose of this study is to provide a methodology to statistically predict the gamma radiation dose rate with minimum surveying in an area. Results of statistical predictions using the hypothesis test were compared with the actual dose rate obtained by measurements.Ahmad Termizi RamliAhmad Taufek Abdul RahmanM.H Lee2009-01-02T01:07:28Z2009-01-02T01:07:28Zhttp://eprints.utm.my/id/eprint/id/eprint/7241This item is in the repository with the URL: http://eprints.utm.my/id/eprint/id/eprint/72412009-01-02T01:07:28ZUnsteady boundary layer flow of a micropolar fluid near the forward stagnation point of a plane surfaceThe growth of the boundary-layer flow of a micropolar fluid started impulsively from rest near the forward stagnation point of a two-dimensional plane surface is studied theoretically. The transformed non-similar boundary-layer equations are solved numerically using a very efficient finite-difference method known as Keller-box method. This method may present well-behaved solutions for the transient (small time) solution and those of the steady-state flow (large time) solution. Numerical results are given for the reduced velocity and microrotation profiles, as well as for the skin friction coefficient when the material parameter K takes the value K=0 (Newtonian fluid), 0.5, 1, 1.5, 2, 2.5 and 3. Important features of these flow characteristics are shown on graphs and in tablesYian Yian LokP. PhangNorsarahaida AminIoan Pop2009-01-02T01:03:52Z2009-01-02T01:03:52Zhttp://eprints.utm.my/id/eprint/id/eprint/7237This item is in the repository with the URL: http://eprints.utm.my/id/eprint/id/eprint/72372009-01-02T01:03:52ZMixed convection boundary layer flow about an isothermal sphere in a micropolar fluid The steady mixed convection boundary layer flow of a micropolar fluid about a sphere with a constant surface temperature is considered for both the assisting and opposing flow cases. The transformed conservation equations of the non-similar boundary layers are solved numerically using a very efficient finite-difference method known as the Keller-box scheme. Numerical results are presented for different values of the material and mixed convection parameters K and Î», respectively, and with the Prandtl number Pr = 0.7 and 7. It is found that assisting flow (Î» > 0) delays separation of the boundary layer and can, if the assisting flow is strong enough, suppress it completely. The opposing flow (Î»<0), on the other hand, brings the separation point nearer to the lower stagnation point of the sphere and for sufficiently strong opposing flows there will not be a boundary layer on the sphere. Some results were given in the form of tables. Such tables are very important and they can serve as a reference against which other exact or approximate solutions can be compared in the futureRoslinda NazarNorsarahaida AminIoan Pop2009-01-02T00:54:49Z2009-01-02T00:54:49Zhttp://eprints.utm.my/id/eprint/id/eprint/7232This item is in the repository with the URL: http://eprints.utm.my/id/eprint/id/eprint/72322009-01-02T00:54:49ZUnsteady mixed convection near the forward stagnation point of a two-dimensional symmetric bodyThe unsteady mixed convection boundary layer flow near the forward stagnation point of a two-dimensional symmetric body resulting from an impulsive motion of the free stream velocity and by sudden increase in the surface temperature. The partial differential equations governing the flow and heat transfer have been solved numerically using Keller-box method. It is shown that there is a smooth transition from the unsteady initial flow (short time) to the final steady state flow(large time). It is also found that for the steady flow case that are dual solutions when the flow is opposing Roslinda NazarNorsarahaida AminIoan Pop2009-01-02T00:50:20Z2009-01-02T00:50:20Zhttp://eprints.utm.my/id/eprint/id/eprint/7229This item is in the repository with the URL: http://eprints.utm.my/id/eprint/id/eprint/72292009-01-02T00:50:20ZThe Brinkman model for the mixed convection boundary layer flow past a horizontal circular cylinder in a porous medium
The Brinkman model is used for the theoretical study of the mixed convection boundary layer flow past a horizontal
circular cylinder with a constant surface temperature and embedded in a fluid-saturated porous medium in a stream
flowing vertically upwards. Both the cases of a heated (assisting flow) and a cooled (opposing flow) cylinder are
considered. It is shown that there are two governing dimensionless parameters, which are related to thermal and viscous effects. These are the Darcyâ€“Brinkman parameter C and the mixed convection parameter k. It is shown that for C Â¼ 0 the problem reduces to the similarity Darcys model, while for C 6Â¼ 0 the governing equations are non-similar and they have been solved numerically using the Keller-box method. It is found that heating the cylinder (k > 0) delays separation of the boundary layer and can, if the cylinder is warm enough (large values of k > 0), suppress it completely. On the other hand, cooling the cylinder (k < 0) brings the boundary layer separation point nearer to the lower stagnation point and for sufficiently cold cylinder (large values of k < 0) there will not be a boundary layer on the cylinder. A complete physical description of the problem is presented throughout the analysis. Some results were given in the form of tables. Such tables are very important and they can serve as a reference against which other exact or approximate solutions can be compared in the futureRoslinda NazarNorsarahaida AminDiana FilipIoan Pop2009-01-01T04:52:01Z2009-01-01T04:52:01Zhttp://eprints.utm.my/id/eprint/id/eprint/7173This item is in the repository with the URL: http://eprints.utm.my/id/eprint/id/eprint/71732009-01-01T04:52:01ZPreparation of crosslinked cation exchange membranes by radiation grafting of styrene/divinylbenzene mixtures onto PFA films
Crosslinked cation exchange membranes bearing sulfonic acid groups were prepared by radiation-induced grafting of styrene containing 2 and 4% divinylbenzene (DVB) onto poly(tetrafluoroethylene-co-perfluorovinyl ether) (PFA) films followed by sulfonation reactions. The degree of grafting was found to be dependent on the grafting parameters including irradiation time and DVB concentration in the bulk solution. The physico-chemical properties of the membranes such as ion exchange capacity, water uptake and ionic conductivity were evaluated in correlation with the degree of grafting and the level of crosslinking. All the properties of the membranes were found to be functions of the degree of grafting. However, crosslinking of polystyrene grafts with DVB was found to considerably reduce the water uptake and the ionic conductivity of the membranes while showing no effect on the ion exchange capacity. The thermal stability of the membranes represented by desulfonation temperature was found to be independent of crosslinking. Membranes having degrees of grafting of 24% (0% DVB), 24% (2% DVB) and 17% (4% DVB) possess good combinations of physico-chemical properties and can be of practical interest.Mohamed Mahmoud NasefHamdani Saidi2008-11-25T03:11:37Z2018-09-22T08:22:35Zhttp://eprints.utm.my/id/eprint/id/eprint/6837This item is in the repository with the URL: http://eprints.utm.my/id/eprint/id/eprint/68372008-11-25T03:11:37ZMathematical models for free and mixed convection boundary layer flows of micropolar fluidsThe phenomena of free and mixed convection are encountered in many industrial and engineering applications, for example, in the cooling of electronic equipment, materials processing and drilling operations. Free convection has also been used to explain the connection between skin disease and respiratory disease such as eczema and asthma. In this study, the mathematical models for steady laminar free and mixed convection boundary layer flows over a horizontal circular cylinder and a sphere immersed in an incompressible micropolar fluid are developed. The theory of micropolar fluid was proposed, as the classical Navier-Stokes theory is inadequate to describe most industrial fluids. Examples of micropolar fluids include polymeric fluids and colloidal suspensions that take into account the microscopic effects arising from the local structures and micromotions of the fluid elements. Both isothermal and nonisothermal boundary conditions are considered. The governing nonlinear partial differential equations are first transformed using an appropriate nonsimilar transformation before they are solved numerically using the Keller-box method, an unconditionally stable implicit finite-difference scheme. Numerical results presented include the velocity, temperature and angular velocity profiles as well as the fluid flow and heat transfer characteristics, for a range of the material parameter or the vortex viscosity K, the Prandtl number Pr, and the mixed convection parameter A. The numerical codes in the form of software packages have been developed using Matlab@. The packages and numerical results presented constitute an invaluable reference against which other exact or approximate solutions can be compared in the future.Roslinda Mohd. Nazar2008-10-08T04:22:51Z2011-05-10T08:58:45Zhttp://eprints.utm.my/id/eprint/id/eprint/6506This item is in the repository with the URL: http://eprints.utm.my/id/eprint/id/eprint/65062008-10-08T04:22:51ZParabolic-elliptic correspondence of a three-level finite difference approximation to the heat equationWe consider three-level difference replacements of parabolic equations focussing on the heat equation in two- space dimensions. Through a judicious splitting of the approximation, the scheme qualifies as an ADI method. Using the well-known fact of the parabolic-elliptic correspondence, we shall derive a two-stage iterative procedure employing a fractional splitting strategy applied alternately at each intermediate time step.M. S. SahimiSallehs@uniten.edu.myN. Aliasnorm_ally@hotmail.comN. A. MansorN. M. Nor2008-09-22T06:41:59Z2018-09-27T04:01:40Zhttp://eprints.utm.my/id/eprint/id/eprint/6433This item is in the repository with the URL: http://eprints.utm.my/id/eprint/id/eprint/64332008-09-22T06:41:59ZIntensification of inclusion body purification and protein refoldingThere is an increasing need to translate genomic information into commercial products through protein expression and production. Formation of the protein as solid inclusion bodies in E. coli is advantageous as it enables good initial purification, provided that acceptable refolding yields can be achieved. However, the recovery of active recombinant protein from complex biological mixtures via the route of IB-formation involves a series of complicated recovery steps, each of which can compromise the purity and yield of the desired product. Purification of IBs using traditional methods of homogenisation and centrifugation are difficult to automate for high-throughput applications, and are costly to scale. Process intensification by minimising the number of unit operations without a loss of product purity is desirable to improve yield and reduce production cost. Such a process should ideally be generic, scalable, easily automated to facilitate continuous processing, and should result in an improved refolding yield. Based on these criteria, an intensified unit operation termed an integrated Membrane Oscillatory Refolding (MOR) is introduced. The integrated MOR unit consists of an oscillatory flow reactor (OFR) that is integrated with a hollow ceramic membrane for cross-flow microfiltration operation. The key is the use of innovative chemical extraction technology in a non-solubilising mode for IB release, coupled with the MOR unit that acts as a novel microfiltration unit for IB purification and protein refolding. The technologies rely only on chemical reagents and on microfiltration that can be easily scaled and automated. The objective of this study is to establish and research the three key process steps essential to realise the integrated MOR unit: a non-solubilising chemical extraction method; a cross-flow microfiltration for IB recovery; and protein refolding via the hollow ceramic membrane in a novel reactor. Three of these process steps, validated using granulocyte macrophage-colony stimulating factor (GM-CSF) IBs, are successfully demonstrated and ready for integration into a single unit of MORChew Tin Lee2007-07-31T03:47:30Z2010-08-13T01:40:59Zhttp://eprints.utm.my/id/eprint/id/eprint/2409This item is in the repository with the URL: http://eprints.utm.my/id/eprint/id/eprint/24092007-07-31T03:47:30ZThe Newton-like properties of the updating mechanism of a model-reality differences algorithmThe Dynamic Integrated Systems Optimization and Parameter Estimation (DISOPE) algorithm is an algorithm for solving nonlinear optimal control problems and is of the gradient descent type. The updating step of DISOPE plays an important role in terminating the iterations of the algorithm and hence in determining its rate of convergence. In this paper, the mechanism was shown to have Newton-like properties and the order convergence establishedRohanin Ahmadrohanin@mel.fs.utm.myMohd. Ismail Abd. Azizm_ismail@mel.fs.utm.my2007-06-27T08:09:54Z2017-10-24T07:00:42Zhttp://eprints.utm.my/id/eprint/id/eprint/3849This item is in the repository with the URL: http://eprints.utm.my/id/eprint/id/eprint/38492007-06-27T08:09:54ZBoundary integral equation approach for conformal mapping, complex boundary value problems, and reproducing kernels.Conformal mapping has been a familiar tool of science and engineering for generations. Its ability to map one planar region onto another via analytic function proves invaluable in applied mathematics. For numerical purposes in conformal mapping, the integral equation methods are more preferable and effective. Of special interest is the Riemann map which maps a simply connected region onto a unit disk. The Riemann map is closely to complex boundary value problem and some reproducing kernels known as the Szego and the Bergman kernels. The fact that there is an efficient numerical method, based on the Kerzman-Stein-Trummer integral equation, for computing the Szego kernel has been known since 1986. The study of the Kerzman-Stein-Trummer integral equation has led to our discovery of a new integral equation for the Bergman kernel which can be used effectively for numerical conformal mapping. This discovery also motivated a general formulation of integral equations associated to certain boundary relationships which can rise to various integral equations (classical and new) related to conformal mapping and boundary value problem of interior, exterior and doubly connected regions. This paper presents some of our past discoveries as well as ongoing research activities regarding the integral equation approach for conformal mapping, complex boundary value problem and reproducing kernels. Ali Hassan Mohamed Muridahmm@mel.fs.utm.myBaharudin Hurminbaharudinhurmin@yahoo.comMohamed M. S. Nassermms_nasser@mel.fs.utm.my2007-06-26T07:41:51Z2017-10-24T06:54:13Zhttp://eprints.utm.my/id/eprint/id/eprint/3835This item is in the repository with the URL: http://eprints.utm.my/id/eprint/id/eprint/38352007-06-26T07:41:51ZAnalytical and numerical methods for the Riemann problemIn this survey we consider the classical and new methods for computing the analytical and numerical solutions to the Riemann problem, a class of boundary value problems for analytic functions, in a simply connected region â„¦+ with smooth boundary Î“ = âˆ‚â„¦+ in the complex plane. The classical methods for solving this problem based on reducing the Riemann problem to the Dirichlet problem or to the Hilbert problem where it is required the availability of a suitable conformal mapping from â„¦+ onto the unit disk D. Recently, the authors introduce a new method for solving the Riemann problem by transforming its boundary condition to a Fredholm integral equation of the second kind with the generalized Neumann kernel. This method has several advantages in terms of numerical operations as well as ease in programming. This paper sketches these classical and new methods and shows the advantages of our method for solving the Riemann problem using Fredholm integral equations.Ali Hassan Mohamed Muridahmm@mel.fs.utm.myMohamed M. S. Nassermms_nasser@mel.fs.utm.my2007-05-22T07:08:56Z2017-07-31T06:56:42Zhttp://eprints.utm.my/id/eprint/id/eprint/2983This item is in the repository with the URL: http://eprints.utm.my/id/eprint/id/eprint/29832007-05-22T07:08:56ZPhotocatalytic oxidation of volatile organic compounds (VOCS) in air using based materialsHeterogeneous photocatalytic oxidation is a promising technique for the removal of volatile organic pollutants (VOCs). It allows the oxidation of gaseous VOCs into carbon dioxide and water in the presence of semiconductor catalyt and UV light. Titanium dioxide (TiO2) represents one of the most efficient photocatalyst. It is chemically stable, non-toxide and low cost. However, the photoexcitation processes of pure TiO2 is only active in the ultra violet fraction of the solar irradiation and although, TiO2 can treate a wide range of VOCs, the effectiveness of the process for the population abatement is still low. Doping TiO2 with metal ions was considered as an alternative method to improve TiO2 photocatalytic properties. In this study, transparent TiO2 thin films were also prepared using the sol-gel and dip-coating method. Various ratios of doped TiO2 thin films were prepared using Cr3+
Mohd. Yusuf Othmanmyusuf@kimia.fs.utm.my2007-05-21T07:46:04Z2012-05-21T03:57:53Zhttp://eprints.utm.my/id/eprint/id/eprint/2680This item is in the repository with the URL: http://eprints.utm.my/id/eprint/id/eprint/26802007-05-21T07:46:04ZDesign and construction a portable computerised ultrasonic cloud point measuring system for oil based products
A cloud point has excited many researchers to study and improve on its quality and production of palm oil. A computer based of ultrasonic system for determination of cloud point of palm oil sample has being developed. The cloud point can be determined as the temperature at which the significant deviations occur in phase velocity and ultrasonic absorption coefficients curves. Ultrasonic signal was displayed by oscilloscope and any changes in temperature will be detected by semiconductor temperature sensor. A special design of ultrasonic Stepped Test Cell is used in this project that will provide an easy operation on data analyzing. The oscilloscope was connected to the computer through a interface card while the temperature sensor circuit was interfaced through a printer port Ultrasonic data acquisition and analysis, and result display will be computed and controlled by a computer software which is written in Microsoft Visual Basic 6.0 programming language. The cloud point for a few palm oil samples were determined and compared with the result obtained from conventional method.
Mohammad Radzi SudinRosly JaafarYaacub Mat DaudShahrul Kadri Ayop2007-05-21T07:35:56Z2017-08-27T06:58:27Zhttp://eprints.utm.my/id/eprint/id/eprint/2700This item is in the repository with the URL: http://eprints.utm.my/id/eprint/id/eprint/27002007-05-21T07:35:56ZSynthesis of non-aqueous ionic liquids derived from n-heterocyclic compoundsResearch in the use of ionic liquid as an alternative solvent for convensional organic solvents in organic synthesis is still in the early stage. In this research, N-methylpyrrolidinium iodide salts have been synthesised from N-methylpyrrolidine with several alkyl iodides. The tetrafluoroborate and hexafluorophosphate salts were synthesised through metathesis reactions with silver tetrafluoroborate and silver hexafluorophosphate respectively. All salts obtained have been characterized using CHN elemental analysis, melting point, density, molar conductivity and 1H-NMR spectroscopy. The melting point range for the N-methylpyrrolidine salts is between room temperature and up to 300Â°C. The correlations between type of anions and alkyl chain length with melting point, density and molar conductivities have been studied. It was found that the length of the alkyl chain has no effect on the melting point of all the iodides, tetrafluoroborates and hexafluorophophates salts. However, the molar conductivities for the salts increase with increasing alkyl chains length and the type or the size of anion. The density of all the salts increase with increasing salts size. This is because salts with bigger size will have a higher density compared with those with smaller size. Room temperature ionic liquids N-methyl-N-propylpyrolidinium tetrafluoroborate (29) and N-butyl-N-methylpyrrolidinium trifluorometanesulfonate (42) has been selected to be used as an alternative for organic solvents in three organic synthesis namely Diels-Alder, Heck and Aldol. In Diels-Alder reactions, the adducts consist of a mixture of exo and endo stereoisomers. The effect of heat towards yield percentage and stereoisomer ratio in the Diels-Alder reactions has been studied. Endo adduct was found to be the main stereoisomer if the reactions were carried out in the presence of heat. In contrast, the exo adduct was the main stereoisomer when the reaction is carried without heat treatment. However, the yield percentages and ratio of exo:endo adducts in ionic liquid solvent are higher than in convensional organic solvents either with or without the presence of heat. In the base catalysed Aldol Condensation reaction, benzaldehyde (59) was reacted with acetone to give dibenzilideneacetone (61), while in the Heck reaction, the ortho, meta and para substituted bromocinnamic acid (58) isomers have been synthesised respectively from the three isomers of bromoiodobenzene (56) and acrylic acid (57). The yield of the products in both the Aldol and Heck reactions are above 80%, which are comparable to the values obtained from similar reactions carried out in conventional organic solvents. Furthermore, the recovery yield of the ionic liquid is sufficiently high, thus render its possibilities for subsequent reactions.
Mustaffa ShamsuddinHasnah Mohd. SiratZakaria BahariSofian IbrahimMohammad Hafiz Ahmad Tajudin2007-05-18T06:38:42Z2017-07-31T07:21:02Zhttp://eprints.utm.my/id/eprint/id/eprint/2988This item is in the repository with the URL: http://eprints.utm.my/id/eprint/id/eprint/29882007-05-18T06:38:42ZPreparation and characterization of polymer electrolytes for lithium batteries based on natural rubber blendsA research on logit, probit and linear probability models have been carried out. The dependent variable being used is binary while the independent variables used consisted of eight variables which were binary, categorical and continuous. Research done based on these models covered its discoveries, functions of models, assumption of residuals, probability distributions and estimation techniques. A case study using the three methods of modeling as mentioned above was carried out. The influential variables were selected being forward stepwise method, backward stepwise method and manual selection. Selected variables using manual selection were based on principle of parsimonious model. For each model, the results showed two out of eight chosen variables were significant at a significance level of 0.05. test on residual, multicollinearity, hypothesis testing, goodness of fit and influences and outliers data diagnostics were applied to these three models. Interpretiations on estimated parameters were also carried out. After comparing the three models, it was found that logit model appeared to be the best model having the highest probability of accuracy. Software like â€˜SPSS for Windows Version 10â€™, â€˜Minitab Release 13.2â€™ and â€˜Microsoft Excel 2000â€™ were used to analyze these data.
Jamil Yusofjamil@kimia.fs.my2007-05-18T06:37:12Z2017-07-31T04:18:02Zhttp://eprints.utm.my/id/eprint/id/eprint/2978This item is in the repository with the URL: http://eprints.utm.my/id/eprint/id/eprint/29782007-05-18T06:37:12ZTo develop a low cost 5mhz pilse NMR spectrometerThe main objective of this project is to build a NMR Spectrometer (nuclear magnetic resonance spectrometer). Tremendous amount of electronic knowledgehas been utilized in this project. This NMR spectrometer includes five sinple circuits and a magnetic field generator. These circuits are time-base circuit, NMR pulse 90â—¦ and ringing damper generator,active probe,RF receiver and transmitter. This NMR spectrometer is operated at 5MHZ frequency by using acrystal oscillator. In this research, the NMR spectrometer has been successfully developed at low cost. The system, which includes two PCBs were designed and created.
Roslinda Zainals-linda@utm.jb.utm.my2007-04-23T06:24:52Z2010-08-13T01:48:46Zhttp://eprints.utm.my/id/eprint/id/eprint/2421This item is in the repository with the URL: http://eprints.utm.my/id/eprint/id/eprint/24212007-04-23T06:24:52ZUse of neural network for modeling of liquid-liquid extraction process in the RDC columnSeveral Mathematical Models have been developed for processes involving Rotating Disc Contactor (RDC) Column. These models indicated that the hydrodynamic and the mass transfer processes are important factors for the column performances. Usually, the mathematical simulation models describing the processes in the column are very complex. It also needs excessive computer time to produce simulation data for further analysis. Therefore, an alternative approach based on Artificial Neural Network is considered to assist in speeding up the simulation process. This paper presents a new application of Artificial Neural Network (ANN) techniques to the modeling of the liquid-liquid extraction process in the RDC Column. In this work, the ANN was trained with the simulated data obtained from Arshad (2000). The Neural Network models are able to generate 128 simulated data for RDC column with RMS error value of 1.0E-07. The comparison between Neural Network output and Mathematical Model(2000) output is also presented.
Normah Maannm@mel.fs.utm.myJamalludin TalibKhairil Annuar Arshad2007-03-22T01:22:44Z2017-11-01T04:17:39Zhttp://eprints.utm.my/id/eprint/id/eprint/2068This item is in the repository with the URL: http://eprints.utm.my/id/eprint/id/eprint/20682007-03-22T01:22:44ZFree convection boundary layer over a nonisothermal vertical flat plateNumerical solutions are presented for the free convection boundary layer problems on a vertical flat plate with prescribed temperature or heat flux distributions, namely the sinusoidal wall temperature and the exponential heat flux variations. The numerical computation is carried out using a very efficient implicit finite difference scheme known as the Keller-box method. Illustrative computational examples are carried out and the present results are compared with previously available theoretical results obtained using other methods of solution, and they are found to be in good agreement. Comparisons of nondimensional temperature gradient for sinusoidal wall temperature variation and of nondimensional wall temperature with exponential variation in wall heat flux are made between the present and previous results. New results for the variation of the surface shear stress with various Prandtl numbers are also presented. In addition, for the case of sinusoidal wall temperature variation, representative velocity and temperature profiles are presented for Prandtl numbers 0.7, 1, 10 and 100, while for the case of exponential heat flux distribution, the velocity and temperature profiles for various transformed streamwise coordinate Ã® = 0, 1, 10 and 100 are illustrated.Roslinda Nazarroslindan@yahoo.comNorsarahaida Aminnsarah@mel.fs.utm.my2007-03-22T01:15:54Z2017-11-01T04:17:40Zhttp://eprints.utm.my/id/eprint/id/eprint/2067This item is in the repository with the URL: http://eprints.utm.my/id/eprint/id/eprint/20672007-03-22T01:15:54ZPenggunaan taburan pareto umum dalam menganalisis nilai ekstrim banjir menggunakan siri aliran puncak melebihi parasSiri banjir tahunan maksimum (Annual Maximum, AM) merupakan pendekatan yang begitu terkenal dalam analisis frekuensi banjir. Siri puncak melebihi paras (peaks over threshold, POT) telah digunakan sebagai alternatif kepada siri banjir tahunan maksimum. Masalah utama dalam pendekatan POT adalah berkaitan pemilihan paras yang sesuai. Dalam kajian ini, kesan perubahaan paras bagi siri POT ke atas nilai anggaran dikaji. Model POT dengan andaian bahawa bilangan puncak melebihi paras bertabur secara Poisson dan magnitud puncak melebehi paras tertabur secara Pareto Umum (General Pareto Distribution, GPD) dibincangkan. Parameter taburan GPD dianggar menggunakan kaedah kebarangkalian pemberat momen (Probability Weighted Moment, PWM) untuk paras yang diketahui. Perbandingan kesesuaian model POT dan model AM dalam menganggarkan nilai hujung atas taburan dibuat. Hasil kajian menunjukkan bahawa apabila paras siri POT boleh disuaikan oleh taburan Pareto dengan proses Poisson, model POT didapati dapat menghasilkan anggaran nilai hujung atas taburan lebih baik berbanding model aliran maksimum.Ani Shabriani_sabri@hotmail.com2007-03-22T01:01:59Z2017-11-01T04:17:39Zhttp://eprints.utm.my/id/eprint/id/eprint/2064This item is in the repository with the URL: http://eprints.utm.my/id/eprint/id/eprint/20642007-03-22T01:01:59ZRangkaian Neural Dalam Peramalan Harga Minyak Kelapa SawitKertas kerja ini membincangkan penggunaan rangkaian neural suap-kehadapan dengan satu aras tersembunyi digabungkan dengan algoritma rambatan balik dan didapati ia sesuai untuk memerihalkan data harga minyak sawit. Kajian awal yang telah dilakukan oleh Azme et al. [1] mendapati analisis regresi berganda kurang sesuai digunakan kerana masalah multikolineariti dalam data kajian. Lima harga minyak sayuran dunia iaitu minyak sawit mentah, minyak isirong, minyak kacang soya, minyak kelapa dan minyak biji sawi telah dianalisis. Dua model telah dicadangkan iaitu, NN1 dan NN2. Hasil kajian mendapati bahawa kedua-dua model telah menunjukkan prestasi yang tinggi dengan mencatatkan nilai pekali penentuan, R2 yang tinggi iaitu 0.938 dan 0.940 masingmasing. Umumnya, rangkaian neural berupaya menjadi satu kaedah alternatif sekiranya masalah multikolineariti wujud terhadap data yang dikaji.Zuhaimy Ismailzhi@mel.fs.utm.myAzme Khamisazmekhamis@hotmail.com2007-03-07T00:55:52Z2017-11-01T04:17:41Zhttp://eprints.utm.my/id/eprint/id/eprint/1467This item is in the repository with the URL: http://eprints.utm.my/id/eprint/id/eprint/14672007-03-07T00:55:52ZA Potential Use Of Dehalogenase D (Dehd) From Rhizobium Sp. For Industrial ProcessThe Rhizobium sp. DehL and DehD were produced by heterologous expression of the cloned gene in E.coli and both proteins purified using anion-exchange column chromatography. DehL and DehD were characterised by kinetic analysis to determine their Km, Kcat and the Specificity constant values. The kinetic analysis results showed that DehD from Rhizobium sp. has lower Km value (0.04 mM with D,L-2-CP) and higher Kcat (6.28 secâ€“1 for D,L-2-CP) and Specificity constants (1.46 Ã— 105 Mâ€“1secâ€“1 for D,L-2-CP) compared to other D-specific dehalogenases from different organism suggesting DehD enzyme from Rhizobium sp. is better catalysts. D-2-haloacid dehalogenase is important for industrial biocatalysis compared to the L-2-haloacid and the kinetic data of DehD hold promise for further development to be used in an industrial process.Fahrul Z. HuyopA. Cooper Ronald2007-03-07T00:47:13Z2017-11-01T04:17:41Zhttp://eprints.utm.my/id/eprint/id/eprint/1464This item is in the repository with the URL: http://eprints.utm.my/id/eprint/id/eprint/14642007-03-07T00:47:13ZSeparation of organophosphorus pesticides using micellar electrokinetic chromatographySeparation of six organophosphorus pesticides (mevinphos, methidathion, diazinon, profenofos, quinalphos and chlorpyrifos) has been investigated using micellar electrokinetic chromatography (MEKC) with on-column UV-Vis detection. Separations involved using anionic sodium dodecyl sulphate (SDS) surfactant and phosphate or borate buffer as carrier electrolytes. Separations have been found incomplete regardless of changing all sort of possible factors such as buffer types, buffer and surfactant concentrations, addition of organic modifier, methanol and pH of the running buffer. Irrespective of the combinations of levels of factors, mevinphos alone appeared always as a distinguishable strong peak followed by diazinon and methidathion. Even in the absence of any surfactant in buffer matrices, mevinphos and diazinon were detected but methidathion, profenofos, quinalphos and chlorpyrifos were undetected. The use of 6 mM b-cyclodextrin (Ã¢ CD), 20 mM borate buffer with 40 mM SDS and buffer pH of 9.5 resulted in the best separation of mevinphos, diazinon and methidathion. The results found in this study might reflect the solubility and hydrophobicity properties of the pesticides.W. Aini W. IbrahimS. M. Monjurul AlamAzli Sulaiman2007-03-07T00:39:49Z2017-11-01T04:17:40Zhttp://eprints.utm.my/id/eprint/id/eprint/1463This item is in the repository with the URL: http://eprints.utm.my/id/eprint/id/eprint/14632007-03-07T00:39:49ZDiagnostic of preliminary breakdown in an artificial thundercloudsLightning is a destructive phenomenon. It can cause fire, damage and electrocute human being and animal. Therefore, we need to have some kinds of protective devices to trigger lightning before it could strike naturally. One way of doing it is by using laser. In this study unfocused UV laser was used to actively discharge the electrodes. Electrodes are used to represent thunderclouds. The separation distance between the electrodes was adjusted to determine the condition for preliminary breakdown. The result showed that, preliminary breakdown occurred at a short ranges separation distance of electrodes, hence very high electric field is required. The breakdown is found stimulated by interfering a UV laser in the thunderclouds. In this respect, the separation distance for breakdown is triple that of without laser. Hence minimum electric field can be achieved for such occurrence of preliminary breakdown.Noriah BidinMadia Pangeran2007-03-07T00:33:32Z2017-11-01T04:17:41Zhttp://eprints.utm.my/id/eprint/id/eprint/1461This item is in the repository with the URL: http://eprints.utm.my/id/eprint/id/eprint/14612007-03-07T00:33:32ZAnalisis kumpulan hidroksil permukaan dan tapak asid zeolit beta daripada abu sekam padi dengan kaedah spektroskopi FTIRAnalisis permukaan ke atas kumpulan hidroksil dan keasidan zeolit adalah penting dalam menentukan keberkesanan zeolit sebagai mangkin heterogen yang baik. Kajian jenis kumpulan hidroksil dan sifat keasidan telah dijalankan ke atas zeolit beta (BEA) yang disintesis daripada abu sekam padi berhablur secara terus pada nisbah SiO2/Al2O3 antara 20 â€“ 90 bagi campuran gel pada suhu 150Â°C. Penentuan kumpulan hidroksil dan keasidan diamati dengan menggunakan kaedah spektroskopi FTIR dan penjerapan piridina sebagai molekul pengesan sifat asid. Keputusan menunjukkan hasil sintesis yang dikalsinkan pada suhu 400Â°C untuk penguraian templat organik menyebabkan pembentukan kumpulan hidroksil bagi silanol terminal dan tapak cacat (3740 cmâ€“1), aluminium luar kerangka (3689 cmâ€“1), dan aluminium kerangka (3608 cmâ€“1). Semakin tinggi nisbah SiO2/Al2O3 sampel, semakin bertambah nisbah kumpulan silanol berbanding hidroksil aluminium kerangka. Regangan hidroksil yang terikat pada aluminium kerangka beranjak kepada frekuensi yang lebih rendah dengan pertambahan nisbah SiO2/Al2O3 gel. Semua sampel menunjukkan kehadiran kedua-dua tapak asid BrÃ¸nsted dan Lewis, dengan jumlah asid BrÃ¸nsted berkurang dengan pertambahan nisbah SiO2/Al2O3.Didik PrasetyokoSalasiah EndudZainab Ramli