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A New Fast Approximate Hilbert Transform with Different Applications
Get PDFA 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
STRUCTURAL IDENTIFICATION OF DISTINCT INVERSIONS OF PLANAR KINEMATIC CHAINS
Get PDFInversions are various structural possibilities of a kinematic chain. The number of inversions depends on the number of links of a kinematic chain. At the stage of structural synthesis, identification of distinct structural inversions of a particular type of kinematic chain is necessary. Various researchers have proposed methods for identification of distinct inversions. Present method based on Link joint connectivity is proposed to identify the distinct inversions of a planar kinematic chain. Method is tested successfully on single degree and multiple degree of freedom planar kinematic chains. ABSTRAK: Penyonsangan merupakan kebarangkalian pelbagai struktur suatu rangkaian kinematik. Jumlah songsangan bergantung kepada jumlah hubungan suatu rangkaian kinematik. Pada peringkat sintesis struktur, pengenalan songsangan struktur yang berbeza untuk suatu jenis rangkaian kinematik adalah perlu. Ramai penyelidik telah mencadangkan pelbagai kaedah pengenalan songsangan yang berbeza. Kaedah terkini berdasarkan hubungan kesambungan bersama telah dicadangkan untuk mengenalpasti songsangan yang berbeza dalam suatu satah rangkaian kinematik
Production of Biosurfactant in 2L Bioreactor Using Sludge Palm Oil as a Substrate
Get PDFIn this study, sludge palm oil was utilized as a raw material for process optimization in a stirred tank bioreactor for the biosurfactant production. Optimized parameters include temperature, agitation and aeration while the pH and media compositions such as NaNO3, NaCl, FeSO4, Meat extract, and glucose have been fixed from the previous study. The design of this research was made by using the Design-Expert software (2 level factorial design). Surface tension was used as indirect indicator for biosurfactant production. After model validation, yield of biosurfactant was found to be highest when surface tension was at its lowest value (<24 mN/m) at temperature of 300C , agitation 300 rpm and around 0.5 vvm of aeration with percentage error less than 10% between observed value and predicted value. The finding in this research can be applied to produce biosurfactant in large amount from the less expensive material such as sludge palm oil by using the same optimized model equation.ABSTRAK: Dalam kajian ini, enapcemar kelapa sawit digunakan sebagai bahan mentah untuk pengoptimuman proses dalam bioreaktor bagi penghasilan biosurfactant. Parameter yang dioptimumkan termasuk suhu, pergolakan dan pengudaraan manakala pH dan komposisi media seperti NaNO3, NaCl, FeSO4, ekstrak daging, dan glukos telah ditetapkan daripada kajian sebelumnya. Reka bentuk kajian ini telah dilakukan dengan menggunakan perisian Design Expert (2 Level factorial design). Tegangan permukaan digunakan sebagai penunjuk tidak langsung untuk penghasilan biosurfactant. Selepas pengesahan, hasil biosurfactant didapati terbanyak apabila tegangan permukaan pada nilai terendah (<24 mN/m) pada suhu 300C, pergolakan 300 rpm, dan sekitar 0.5 vvm pengudaraan dengan margin perbezaan kurang daripada 10% antara nilai sebenar cerapan dan nilai yang diramalkan. Penemuan dalam kajian ini boleh digunakan untuk menghasilkan biosurfactant dalam jumlah yang besar dari bahan yang murah seperti enapcemar kelapa sawit dengan menggunakan model optimum yang sama.KEY WORDS: Biosurfactant, Sludge Palm Oil, Process optimization, and Factorial design
Molecular Cloning of Phytase Gene from ASUIA279 and Its Expression in Pichia pastoris System
Get PDFPhytases catalyze the hydrolysis of phytate (myo-inositol hexakisphosphate), one of the major storage form of phosphate in plants, with subsequent release of myo-inositol, phosphate and phytate-bound minerals. Non-ruminant animals such as chicken, swine and fish can't use the organic phosphorus and minerals from their diet because there is no phytase activity in their digestive tract. Phytate degrading enzyme is added to the animal feed diet to improve phosphorus availability from the dietary phytate and at the same time this lessen the phosphate pollution level in areas of intensive animal production as the phosphate would not be excreted out to the environment. ASUIA279, a bacterial strain isolated from Malaysian soil has potentially shown good phytase activity. In the present work, the gene encoding for phytase has been amplified from the plasmid DNA of recombinant ASUIA279(5) obtained from a previous study (unpublished data) by a polymerase chain reaction (PCR) methodology. The amplified phytase gene was extracted, purified then cloned into the pPICZï¡A plasmid and transformed into Pichia pastorisX-33 strain for enzyme production.ABSTRAK: Fitase pemangkinan hidrolisis fitat (myo-inositol hexakisphosphate), merupakan salah satu cara penyimpanan utama fosfat dalam tumbuhan, dengan pelepasan berturut myo-inositol , fosfat dan galian terikat fitat. Haiwan bukan ruminan seperti ayam, khinzir dan ikan tidak dapat memanfaatkan fosforus organik serta galian yang diperolehi daripada makanan kerana tidak mempunyai aktiviti fitase di dalam saluran pencernaan mereka. Enzim pengecilan fitase dicampurkan ke dalam pemakanan haiwan untuk mempertingkatkan keperolehan fosforus dari fitat diet. Pada masa yang sama ia dapat mengurangkan tahap pencemaran fosfat di kawasan yang terdapat penternakan haiwan secara intensif agar fosfat tidak dikumuhkan ke persekitaran. ASUIA279, satu strain bakteria yang diasingkan daripada tanih di Malaysiamenunjukkan aktiviti fitase yang memberansangkan. Buat masa kini, pengekodan gen fitase telah diperkuatkan dengan plasmid DNA dari ASUIA279(5), rekombinan yang diperolehi daripada kajian terdahulu (data tak diterbitkan) berdasarkan kaedah tindak balas berantai polimerase (polymerase chain reaction (PCR)). Gen fitase yang diperkuatkan, ditulenkan dan kemudian diklonkan menjadi plasmid pPICZαA dan berubah menjadi strain Pichia pastorisX-33 untuk penghasilan enzim.KEYWORDS: Phytase, animal feed, pollution, polymerase chain reaction (PCR), Pichia pastori
Adaptation of Cholesterol Requiring NS0 Cells to Serum Free Culture Conditions
Get PDFColorectal cancer is the third most common form of cancer and the second leading cause of cancer-related death in the Western world. The answers to such life threatening diseases and cancers are monoclonal antibodies (MAb's) which are widely used as therapeutic agents. World demand for currently approved MAb's is on the order of a few kilograms per year. However, new therapeutic MAb's are under development and require doses of several hundred milligrams to a gram over the course of therapy. Very often to cater for the special requirements for the growth of mammalian cells, serum is added to the cell culture medium. However, removal of serum from the cell culture medium is often carried out, especially if the end product is to be used for human consumption, in order to eliminate various disadvantages such as high physiological variability, high batch to batch variability, risk of contamination and high cost, and challenges posed in the downstream processing of the product. In this paper, the adaptation of cholesterol requiring NS0 cells to commercially available serum free media is presented. ABSTRAK: Kanser kolorektum merupakan kanser ketiga paling umum dan kini berada di tempat kedua penyebab kematian berkaitan kanser di negara Barat. Jawapan kepada penyakit yang mengancam nyawa dan penyakit kanser adalah antibodi monoklon (monoclonal antibodies ((MAb's)) yang digunakan sebagai agen terapeutik. Permintaan dunia terhadap MAb's yang diluluskan adalah dalam bilangan beberapa kilogram setahun. Namun, terapeutik MAb's yang baru adalah di bawah penyelidikan dan memerlukan beberapa ratus dos milligram hingga satu gram dalam satu peringkat terapi. Sering kali untuk memenuhi permintaan terhadap tumbesaran sel mamalia, serum dicampurkan dengan sel kultur perantara. Walaupun begitu, pemindahan serum dari sel kultur perantara sering dilakukan, terutamanya jika produk akhir digunakan untuk kegunaan manusia; untuk mengurangkan pelbagai kelemahan seperti kebolehubahan psikologi yang tinggi, kebolehubahan yang tinggi daripada satu kumpulan ke satu kumpulan lain, risiko pencemaran, kos yang tinggi, dan cabaran mendatang dalam pemprosesan produk. Dalam perbentangan ini, kolestrol yang diubah memerlukan sel NS0 yang dikomersilkan dengan serum bebas perantara
ANALYSIS OF WEB MINING APPLICATIONS AND BENEFICIAL AREAS
No full textThe main purpose of this paper is to study the process of Web mining techniques, features, application ( e-commerce and e-business) and its beneficial areas. Web mining has become more popular and its widely used in varies application areas (such as business intelligent system, e-commerce and e-business). The e-commerce or e-business results are bettered by the application of the mining techniques such as data mining and text mining, among all the mining techniques web mining is better
Isolation and Analytical Characterization of Local Malaysian Leech Saliva
Get PDFLeech saliva contains biologically active compounds that are mainly proteins and peptides. In this study a modified and smooth extraction method of saliva was used without leeches' scarification. UV and Bradford Assay protein methods showed that the saliva extract contains high concentrations of proteins. RP-HPLC chromatogram revealed that more than 30 different peaks were observed in leech saliva extract. Gel electrophoresis revealed the existence of proteins and peptides with different molecular weights. The gel showed up to 25 different bands. Comparison of gel electrophoresis data with protein database revealed the closeness of four molecular weights to known proteins from Hirudinaria leech family. Other proteins detected by gel electrophoresis may be related to completely new biologically active proteins and peptides in the saliva extract or to a modification (isoforms) of the existing ones or finally to a mixture of both.ABSTRAK: Air liur pacat secara biologinya mengandungi sebahagian besar campuran aktif protein dan peptida. Dalam kajian ini, kaedah pengestrakan air liur pacat yang telah diubah suai digunakan tanpa perlu membunuh pacat. Kaedah protein Cerakin UV dan Bradford menunjukkan air liur pacat yang diekstrak mengandungi konsentrasi protein yang tinggi. Kromatogram RP-HPLC memperlihatkan lebih daripada 30 puncak berbeza diperolehi semasa air liur pacat diekstrak. Gel elektroforesis memperlihatkan kewujudan protein dan peptida dengan berat molekul yang berbeza. Gel menunjukkan hingga 25 jalur yang berbeza. Perbandingan data menggunakan gel elektroforesis seiring dengan pangkalan data protein memperlihatkan persamaan empat berat molekul, dengan protein yang yang dikenali daripada keluarga pacat Hirudinaria. Jenis protein lain yang dikesan dengan menggunakan gel elektrofosis mungkin juga berkait secara biologinya dengan protein dan peptida aktif yang baru, dalam ekstrak air liur atau pengubahsuaian (beberapa jenis yang berbeza daripada protein yang sama) daripada yang sedia ada ataupun gabungan kedua-duanya.KEY WORDS : leech saliva; RP-HPLC; gel electrophoresis
Risk Factors for Prostate Cancer Patients Among Gezira State-Central of Sudan
Get PDFThe aim of this study is to assess the risk factors for prostate cancer among Sudanese patients treated in National Cancer Institute (NCI), Gezira University, Wadmedani, Sudan. The study was performed on 268 prostate cancer patients, age ranging between 45-98 years. Similar number of 268 persons (age and sex matched) was used as control group .The study period was from May-2006 to December-2009. Data was collected from patients using a questionnaire which was filled in order to obtain information regarding: age, residence, tribe, education levels, occupation, marital status, stage of disease, family history and habits .The body mass index (BMI) was determined by anthropometrics measurements ( weight& height). Prostate cancer is the commonest cancer among male patients treated in the NCI. The mean age of patients was 72.2±9.25. Most of patients (73.9%) were over 66-years. Family history is positive in 18(6.7%) of the patients. Rural inhabitants were 79.8% of all cases. The disease is equally distributed among different tribes. The illiteracy among cases is 39.1%. The commonest occupation was farming (60.1%). Majority (90.7%) of the patients were married. Most cases (85.4%) presented with stage ІІІ and ІV. 73% of the patients had one or more of unhealthy habits (smoking, snuff and alcohol). the BMI was high in 6.9% of the patients. Risk factors for prostate cancer in the study area, which may appear to have a high significant effect, were: the age, education level, occupation, unhealthy habits and the BMI. ABSTRAK: Tujuan kajian ini dijalankan ialah untuk menilai faktor-faktor risiko untuk kanser prostat di kalangan pesakit-pesakit yang dirawat di Institut Kanser Kebangsaan (NCI), Universiti Gezira, Wadmedani, Sudan. Kajian dijalankan pada 268 pesakit kanser prostat, berumur di antara 45-98 tahun. Jumlah bilangan pesakit yang sama iaitu seramai 268 orang (sama umur dan jantina) telah digunakan sebagai kumpulan kawalan.Tempoh kajian ialah pada Mei 2006 sehingga Disember 2009. Data diperolehi daripada pesakit-pesakit dengan menggunakan boring soal selidik yang diisi untuk mendapatkan maklumat: umur, tempat tinggal, puak, taraf pendidikan, pekerjaan, status perkahwinan, peringkat penyakit, sejarah keluarga dan tabiat-tabiat. Indeks jisim badan (BMI) telah ditentukan melalui pengukuran antropometri (berat dan ketinggian). Kanser prostat ialah kanser yang paling banyak dihidapi pesakit-pesakit yang dirawat di NCI. Purata umur ialah 72.2±9.25. Kebanyakan pesakit (73.9%) berumurlebih 66 tahun. Sejarah keluarga ialah positif pada 18 (6.7%) pesakit. Penduduk luar bandar ialah 79.8% daripada keseluruhan jumlah kes. Penyakit ini terbahagi sama rata di antara puak-puak. Kadar buta huruf di antara kes-kes ialah 39.1%. Pekerjaan yang paling banyak ialah bertani (60.1%). Majoriti (90.7%) pesakit telah berkahwin. Kebanyakan kes-kes (85.4%) menghidapi peringkat III dan IV penyakit. 73% daripada jumlah pesakit mempunyai satu atau lebih tabiat yang kurang sihat (merokok, menghidu, dan alkohol). 6.9% pesakit mempunyai indeks jisim badan (BMI) yang tinggi. Faktor-faktor risiko untuk kanser prostat di dalam kawasan kajian yang menunjukkan kesan signifikan yang tinggi ialah: umur, taraf pendidikan, pekerjaan, tabiat-tabiat kurang sihat dan indeks jisim badan (BMI)
VARIABILITY ANALYSIS OF 6T AND 7T SRAM CELL IN SUB-45NM TECHNOLOGY
Get PDFThis paper analyses standard 6T and 7T SRAM (static random access memory) cell in light of process, voltage and temperature (PVT) variations to verify their functionality and robustness. The 7T SRAM cell consumes higher hold power due to its extra cell area required for its functionality constraint. It shows 60% improvement in static noise margin (SNM), 71.4% improvement in read static noise margin (RSNM) and 50% improvement in write static noise margin (WSNM). The 6T cell outperforms 7T cell in terms of read access time (TRA) by 13.1%. The write access time (TWA) of 7T cell for writing "1" is 16.6 x longer than that of 6T cell. The 6T cell proves it robustness against PVT variations by exhibiting narrower spread in TRA (by 1.2 x) and Twa (by 3.4x). The 7T cell offers 65.6% saving in read power (RPWR) and 89% saving in write power (WPWR). The RPWR variability indicates that 6T ell is more robust against process variation by 3.9x. The 7T cell shows 1.3x wider write power (WPWR) variability indicating 6T cell's robustness against PVT variations. All the results are based on HSPICE simulation using 32 nm CMOS Berkeley Predictive Technology Model (BPTM)
DESIGN AND IMPLEMENTATION OF POTENTIOMETER-BASED NONLINEAR TRANSDUCER EMULATOR
Get PDFThis work attempts to design and implement in hardware a transducer with a nonlinear response using potentiometer. Potentiometer is regarded as a linear transducer, while a the response of a nonlinear transducer can be treated as a concatenation of linear segments made out of the response curve of an actual nonlinear transducer at the points of inflections being exhibited by the nonlinear curve. Each straight line segment is characterized by its slope and a constant, called the y-intercept, which is ultimately realized by a corresponding electronic circuit. The complete circuit diagram is made of three stages: (i) the input stage for range selection, (ii) a digital logic to make appropriate selection, (iii) a conditioning circuit for realizing a given straight-line segment identified by its relevant slope and reference voltage. The simulation of the circuit is carried using MULTISIM, and the designed circuit is afterward tested to verify that variations of the input voltage give us an output voltage very close to the response pattern envisaged in the analytical stage of the design. The utility of this work lies in its applications in emulating purpose built transducers that could be used to nicely emulate a transducer in a real world system that is to be controlled by a programmable digital system