977 research outputs found

    Ferroelectric properties of PVDF-TrFE (70:30 mol%)/MgO nanocomposite thin film / Mohamad Hafiz Mohd Wahid

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    This research proposed study on new nanocomposite material for the application of electrical devices, which utilized fluoropolymer and nanofiller. Nanocomposite thin films with MgO loading percentages of 1, 3, 5, and 7 % incorporated in PVDF-TrFE polymer matrix were produced by spin coating technique on Al-glass substrates. The PVDFTrFE thin films were annealed and recrystallized in accordance to the transition temperatures (Tc, Tm and Tcrys) of PVDF-TrFE determined through the observation of the DSC spectra. The annealed PVDF-TrFE thin film (AN113) showed significant improvement in the ferroelectric properties with rectangular shape hysteresis loops for a range of applied voltage. Most importantly, the annealed AN113 film sustained electrical breakdown unlike the recrystallized thin films (RC154, RC135 and RC55). The Pr value recorded for AN113 thin film at applied voltage of 100 V was 77 mC/m2, with Ec of 88 MV/m. The morphology of AN113 thin film was also observed to be defect free, as evident from FESEM images. The high intensity peaks at 1288 cm-1 and 845 cm-1, observed from the FTIR spectrum showed most of the dipoles in AN113 thin film were aligned parallel to the b-axis. Further annealing of PVDF-TrFE thin film at 120˚C (AN120), showed a significant increased in the Pr to a value of 93 mC/ m2 and Ec of 74 MV/m at 100 V applied voltage. With the incorporation of MgO nanofiller in PVDF-TrFE, the AN120/3%MgO nanocomposite thin film showed the highest Pr of 88 mC/m2 with Ec of 79 MV/m at 100 V, relative to the Pr and Ec values obtained for nanocomposite thin films filled with MgO at loading percentages of 1, 5 and 7%. Further increased in MgO loading percentage, produced a drop in crystallinity, as shown by the decrement in the XRD peak diffraction at 2θ = 19.2˚. It is noteworthy to mention that from the observation of the XRD peak diffraction patterns, peak at 2θ = 17.5˚emerged for AN120/5%MgO and AN120/7%MgO films, which indicated the presence of α phase crystals in these nanocomposite films. These unfavourable non-polar crystals have little contribution to ferroelectric properties of the nanocomposite thin films. Therefore, it is established in this study, the favourable thin film produced with enhanced ferroelectric was the annealed PVDFTrFE thin film at 120˚C and loaded with 3% MgO nanofiller

    The Role of the Respiratory Mucosal Immunity in Protection against Pasteurella Haemolytica A2 Infection in Goats

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    Pneumonic pasteurellosis is one of the most important and devastating diseases in sheep and goats, causing great economic losses to small ruminant industry worldwide. The disease is caused either by Pasteurella haemolytica or Pasteurella multocida and Pasteurella haemolytica A2 is the most common isolate from sheep and goats in Malaysia, comprising approximately 38 per cent of the isolates from pneumonic lung lesions. The disease is best controlled by vaccination, and systemic vaccination has been used for years with limited success. Stress, improper vaccination program and unpopularity of the vaccine among the farmers are some of the reasons that have been associated with the persistence of the disease. Since the systemic vaccination failed to give promising results, studies on the role of mucosal immunity of the respiratory tract in controlling pneumonic pasteurellosis should timely be reviewed. In this study, the bronchus-associated lymphoid tissue (SALT) in the lungs 9 been successfully stimulated by double intranasal exposures to either live or formalin-killed Pasteurella haemolytica A2 at two weeks interval. The size of SALT and number of lymphocytes in the SALT were significantly increased as early as week 2 post-exposure and remained high until week 4 post-exposure. At the same time, the level of IgA against Pasteurella haemolytica A2 increased significantly as early as week 1 post-first exposure and reached a peak level at week 6 post-exposure. The IgM appeared to be present for a short while, at week 3 post-exposure before the levels started to decline in the following week. Initially, the IgG increased gradually and insignificantly before it reached significantly high level at week 4 post-exposure, and remained high at weeks 5 and 6 at the time when the numbers of SALT continued to increase. This study also revealed that intranasal stimulation of SALT was able to protect the lungs from colonization by Pasteurella haemolytica A2 during an in vitro study, thus prevent the lung surface from being adhered and invaded by the organism. However, dexamethasone treatment which is similar to the effect of steroid released under stressful conditions, significantly reduced the number and size of the SALT, thus significantly reduced the percentage of IgA-producing cells. Vaccination trial on goat farm using the pasteurella spray vaccine intranasally showed good protection towards pneumonic pasteurellosis. Significant high levels of systemic antibody responses were also noted during the period of vaccination trial. The incidence of pneumonic pasteurellosis in the farm was markedly reduced

    Comparative analysis of support vector machine, maximum likelihood and neural network classification on multispectral remote sensing data

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    Land cover classification is an essential process in many remote sensing applications. Classification based on supervised methods have been preferred by many due to its practicality, accuracy and objectivity compared to unsupervised methods. Nevertheless, the performance of different supervised methods particularly for classifying land covers in Tropical regions such as Malaysia has not been evaluated thoroughly. The study reported in this paper aims to detect land cover changes using multispectral remote sensing data. The data come from Landsat satellite covering part of Klang District, located in Selangor, Malaysia. Landsat bands 1, 2, 3, 4, 5 and 7 are used as the input for three supervised classification methods namely support vector machines (SVM), maximum likelihood (ML) and neural network (NN). The accuracy of the generated classifications is then assessed by means of classification accuracy. Land cover change analysis is also carried out to identify the most reliable method to detect land changes in which showing SVM gives a more stable and realistic outcomes compared to ML and NN

    3 dekad pembangunan kampus UTM

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    Buku 3 Dekad Pembangunan Kampus UTM merupakan hasil pengumpulan maklumat daripada koleksi kertas kerja, laporan projek–projek pembangunan, buku serta majalah berkaitan yang bertujuan bagi mendokumentasikan sejarah pembangunan UTM. Perlaksanaan pembangunan kampus baru UTM ini telah dimulakan sejak tahun 1973. Sejarah penamaan kampus kepada Universiti Teknologi Malaysia tercatat pada 1 April 1975 apabila ITK dinaik taraf kepada UTM. Buku ini juga menceritakan konsep pembangunan yang dilaksanakan serta mengambil kira beberapa kriteria perancangan bagi melancarkan perlaksanaan projek dari Rancangan Malaysia Ke–3 sehinggalah Rancangan Malaysia Ke–8. Pembangunan kampus induk baru ini juga mengambil kira pembangunan persekitaran yang kondusif serta mengekalkan aspek penghijauan di seluruh kampus supaya suasana pembelajaran dan pengajaran dapat dilaksanakan dengan harmoni. Selain itu, pelbagai kemudahan disediakan untuk menjadikan kampus induk ini bertaraf antarabangsa dengan cara permohonan peruntukan untuk projek–projek pembangunan berasaskan keperluan pengajaran, pembelajaran, penyelidikan, penulisan serta pengkomersilan universiti menerusi peruntukan Rancangan Malaysia setiap 5 tahun. Buku ini diharap menjadi sumber rujukan penting dan komprehensif bagi membantu mereka yang terlibat secara langsung atau tidak langsung dalam perancangan projek pembangunan kampus di Malaysia

    Hybrid harmony search with great deluge for UUM CAS curriculum based course timetabling

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    Producing university course timetabling is a tough and complicated task due to higher number of courses and constraints.The process usually consisted of satisfying a set of hard constraints so as a feasible solution can be obtained.It then continues with the process of optimizing (minimizing) the soft constraints in order to produce a good quality timetable. In this paper, a hybridization of harmony search with a great deluge is proposed to optimize the soft constraints.Harmony search comprised of two main operators such as memory consideration and random consideration operator.The great deluge was applied on the random consideration operator. The proposed approach was also adapted on curriculum-based course timetabling problems of College of Arts and Sciences, Universiti Utara Malaysia (UUM CAS).The result shows that the quality of timetable of UUM CAS produced by the proposed approach is superior than the quality of timetable produced using the current software package

    Kesedaran membayar zakat: Apakah faktor penentunya?

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    The awareness of the responsibility to pay (zakat) on property is still perceived to be very low among the zakat payers. This is perhaps due to the misunderstanding of the Muslim masses that the only responsibility to pay zakat is (fitrah) in the month of Ramadan. In this case the role of Islamic teaching plays a pivotal role in educating the Muslim through a law that enforces payment and the integrity of the zakat Institution. Because of the stated weaknesses, there exist certain individuals that have no legitimate reasons not to pay zakat, while some pay to unauthorised individuals or organizations. This problem of zakat evasion also represents the stealing of the wealth of others that lies in our property. Thus, this study aims to identify significant factors that contribute toward the payment of zakat relating to location, demographic, facility and educational factors. A logistic regression model was used to identify the variables. Results of the econometric analysis showed that payer satisfaction of zakat distribution is one of the significant factors and several suggestions are given to improve the awareness among the payers

    A Comparative Analysis of Web Search Query: Informational Vs. Navigational Queries

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    The search engines are mainly used to retrieve relevant information. Information retrieval researchers show that queries are the basis for providing better search engine performance. The search query is becoming a means for users to search for their needed information. Web search query is one of the common search queries that is widely used in domain areas. However, the main challenge is the absence of a clear understanding of how web search query influences the users’ behavior on different web search engines. With the emergence of different types of a web search query, the understanding of user behavior on a web search query guides in improving the performance of many web search engines. Current research focused on using informational queries to search relevance information from a database while ignoring the importance of navigational queries. In this paper, we compared the informational and navigational type of a web search query that is mostly used in academic settings. Specifically, we examine the problems, solutions and techniques used in each of these types. We used a query log to conduct an experiment using BM25 mathematical model. The results indicated that the informational search query performed best because several keywords have been included to properly explain the queries. Also, language vocabularies used in informational queries contributed to better search performance. We believed that the outcomes of our comparisons will guide web search engine developers on the right search query for their web search engines

    M-Hafazan: aplikasi mudah alih untuk pengajian tahfiz

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    Pendidikan tahfiz secara formal telah berkembang pesat serta mendapat perhatian istimewa dari masyarakat Islam di Malaysia. Perkembangan ini disebabkan oleh kesedaran dan permintaan ibu bapa dalam menerapkan al-Quran kepada anak-anak melalui hafazan. Pada masa kini, terdapat banyak aplikasi yang dapat menyokong pembelajaran tahfiz. Namun begitu, tiada aktiviti pengukuhan disediakan bagi membolehkan penghafaz al-Quran menguji tahap ingatan mereka terhadap ayat-ayat yang telah dihafaz. Aplikasi m-Hafazan ini dibangunkan dengan tujuan menyokong pengajian tahfiz dengan lebih baik. Aplikasi ini dibangunkan dengan menggunakan metodologi Multimedia Mobile Content Development. Metodologi ini dipilih kerana ia dapat mempercepatkan proses pembangunan aplikasi serta mengurangkan penggunaan pemprosesan data peranti mudah alih. Pengujian aplikasi telah dijalankan terhadap pelajar-pelajar dan guru dari Sekolah Rendah Islam Tahfiz, Parit Raja. Hasil pengujian menunjukkan 78.3% pelajar sangat bersetuju aplikasi m-Hafazan sesuai digunakan sebagai medium alternatif dalam pengajian hafazan al-Quran. Selain itu, 85% pelajar sangat bersetuju bahawa aplikasi ini dapat membantu pengukuhan hafazan mereka. Kesimpulannya, walaupun kaedah talaqqi (bersemuka) merupakan pendekatan yang terbaik dalam pengajian hafazan, namun implementasi aplikasi m-Hafazan berpotensi untuk dijadikan kaedah alternatif dalam pembelajaran hafazan bagi pelajar tahfiz mahupun bukan

    DESIGN AND DEVELOPMENT OF ANTENNA FOR THE SCALE DOWN MODEL OF A SEA BED LOGGING (SBL) FACILITY

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    Controlled-source electromagnetic (CSEM) methods had been used for marine geological surveying for many years. The electromagnetic (EM) technique for marine hydrocarbon prospecting which first used commercially, has gained wide industry acceptance and many improvements have been made to operating practices, survey equipment, and data-processing techniques in the past few years. The objective of this project is to improve a small scale of SBL model measurement facility that had been earlier developed at Universiti Teknologi Petronas (UTP), to develop a better, well develop electrical dipole antenna to collect experimental data such as resistance and magnetic field measurement, and to verify the result through theoretical modeling. The lab scale model of SBL system was completed with several specification changes and modifications. Modifications are needed in order to simulate different skin depth effect. Theoretical modeling is done before lab experimentation is performed. Several experimentations have been made and the result is not very accurate. It is still unclear if there are something buried in the sand from the reading of the receiver. Therefore several factors have been identified to be the cause of the invalid result. Thus, future works based on current problem are also suggested

    The study of probability model for compound similarity searching

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    Information Retrieval or IR system main task is to retrieve relevant documents according to the users query. One of IR most popular retrieval model is the Vector Space Model. This model assumes relevance based on similarity, which is defined as the distance between query and document in the concept space. All currently existing chemical compound database systems have adapt the vector space model to calculate the similarity of a database entry to a query compound. However, it assumes that fragments represented by the bits are independent of one another, which is not necessarily true. Hence, the possibility of applying another IR model is explored, which is the Probabilistic Model, for chemical compound searching. This model estimates the probabilities of a chemical structure to have the same bioactivity as a target compound. It is envisioned that by ranking chemical structures in decreasing order of their probability of relevance to the query structure, the effectiveness of a molecular similarity searching system can be increased. Both fragment dependencies and independencies assumption are taken into consideration in achieving improvement towards compound similarity searching system. After conducting a series of simulated similarity searching, it is concluded that PM approaches really did perform better than the existing similarity searching. It gave better result in all evaluation criteria to confirm this statement. In terms of which probability model performs better, the BD model shown improvement over the BIR model
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