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Comparison between Scheduling Techniques in Long Term Evolution
Get PDFLong-Term Evolution (LTE) is a recently evolving technology characterized by very high speed data rate that allows users to access internet through their mobile as well as through other electronic devices. Such technology is intended to support variety of IP-based heterogeneous traffic types. Traffic scheduling plays an important role in LTE technology by assigning the shared resources among users in the most efficient manner. This paper discusses the performance of three types of scheduling algorithms namely: Round Robin, best Channel Quality Indicator (CQI) and Proportional Fair (PF) schedulers representing the extreme cases in scheduling. The scheduling algorithms performances on the downlink were measured in terms of throughput and block error rate using a MATLAB-based system level simulation. Results indicate that the best CQI algorithm outperforms other algorithms in terms of throughput levels but on the expense of fairness to other users suffering from bad channel conditions. ABSTRAK: Teknologi baru Evolusi Jangka Panjang (LTE) sentiasa berubah dan ia bercirikan kelajuan kadar data sangat tinggi yang membolehkan pengguna mengakses internet melalui telefon bimbit dan peranti elektronik lain. Teknologi seperti ini bertujuan menyokong pelbagai jenis trafik heterogen berasaskan IP. Penjadualan trafik memainkan peranan penting dalam teknologi LTE bagi mengagihkan sumber perkongsian secara paling berkesan di kalangan pengguna. Kertas ini membincangkan prestasi tiga jenis algoritma penjadualan iaitu: pusingan Robin, penunjuk kualiti saluran (CQI) terbaik dan penjadualan berkadar adil (PF) yang merupakan kes ekstrem dalam penjadualan. Prestasi penjadualan Algoritma di pautan turun diukur dari segi daya pemprosesan dan kadar ralat blok melalui simulasi sistem menggunakan MATLAB. Hasil kajian menunjukkan algoritma CQI adalah yang terbaik berbanding hasil algoritma lain dari segi tahap daya pemprosesan tetapi algoritma ini menyebabkan pengguna lain mengalami keadaan saluran buruk.KEYWORDS: LTE; round robin; best CQI; proportional fair; scheduling; resource block
INVESTIGATION OF GEOTECHNICAL SPECIFICATIONS OF SAND DUNE SOIL: A CASE STUDY AROUND BAIJI IN IRAQ
Get PDFABSTRACT: While more than half the land surface of Iraq consists of deserts covered mainly with sand dunes, little research has taken place to study the characteristics and the behavior of dune soils. This paper directed toward studying the geotechnical properties of dune sands taken from Baiji city (northwest of Iraq). A vast laboratory testing program was carried out to achieve the purpose of this paper. The physical tests, chemical tests, X-ray diffraction analysis, permeability test, compaction characteristics, compressibility and collapsibility tests; and shear strength tests were included in this program. The results indicate that soil of Baiji sand dune exhibits prefer engineering properties according to their state. As such, this soil is considered suitable for use in geotechnical constructions. ABSTRAK: Walaupun lebih separuh daripada bumi Iraq terdiri daripada gurun yang dipenuhi dengan bukit-bukit pasir, tidak banyak penyelidikan dijalankan untuk mengkaji sifat-sifat dan ciri-ciri tanah pasir tersebut. Kertas kerja ini menyelidik sifat geoteknikal bukit pasir yang diambil dari pekan Baiji (di bahagian barat utara Iraq). Program penyelidikan makmal yang menyeluruh telah dijalankan bagi mencapai objektif kajian ini. Ujian fizikal, ujian kimia, analisis belauan sinar-x, ujian kebolehtelapan, ciri pemadatan, faktor ketermampatan, ujian keruntuhan dan ujian kekuatan ricih diambilkira dalam program ini. Keputusan menunjukkan bahawa tanih bukit pasir Baiji mengutamakan ciri kejuruteraan berdasarkan keadaannya. Oleh itu, tanah ini dianggap sesuai untuk kegunaan pembinaan geoteknikal
Numerical Study of Laminar Forced Convection of Water/Al2o3 Nanofluid in an Annulus with Constant Wall Temperature
Get PDFLaminar forced convection of a nanofluid consisting of water and Al2O3 in a horizontal annulus has been studied numerically. Two-phase mixture model has been used to investigate thermal behaviors of the nanofluid over constant temperature thermal boundary condition and with different volume concentration of nanoparticles. Comparisons with previously published experimental and analytical works on flow behavior in horizontal annulus show good agreements between the results as volume fraction is zero. In general convective heat transfer coefficient increases with nanoparticle concentration. ABSTRAK: Kertaskerja ini mengkaji secara numerik olakan paksa bendalir lamina yang menganduangi air dan Al2O3 didalam anulus mendatar. Model campuran dua fasa digunakan bagi mengkaji tingkah laku haba bendalir nano pada keadaan suhu malar dengan kepekatan nanopartikel berbeza. Perbandingan dengan karya eksperimen dan analitikal yang telah diterbitkan menunjukkan bahawa kelakuan aliran didalm anulus mendatar adalah baik apabila pecahan isipadu adalah sifar. Pada amnya, pekali pemindahan haba olakan meningkat dengan kepekatan nanopartikel. KEYWORDS: nanofluid; volume concentration; heat transfer enhancement; laminar flow convection; annulu
A VOLTAGE STABILIZER FOR A MICROGRID SYSTEM WITH TWO TYPES OF DISTRIBUTED GENERATION RESOURCES
Get PDFABSTRACT: Microgrids are used as controllable units connected to power grid, in which the electrical distances between reactive power sources and the loads that need the reactive compensation are not too much. Thus, a coordinated compensation of reactive sources has to be implemented in order to avoid a fast voltage collapse by proposing a Microgrid Voltage Stabilizer (MGVS). This stabilizer is desirable to improve the dynamic voltage profile and is tested at a 21-bus IEEE microgrid system. In order to verify the performance of this stabilizer, three distributed generation (DG) resources are utilized in this microgrid (Two PV resources which are categorized as power-electronic converter based on DG and a diesel generator which is known as synchronous machine-based on DG). At first, the mentioned resources and all of their needed equipments are modeled. Then a control model of the stabilizer with appropriate parameters for the proposed microgrid is presented. Voltage deficiency of the system is the input of the stabilizer, and the output signal of the stabilizer, is divided between the DGs in order to provide required reactive power. The dynamic voltage profile of buses in the presence of MGVS and its absence has been compared by implying disturbances. Simulation results in MATLAB/SIMULINK show that the dynamic voltage profile of the buses improves satisfactorily with the addition of MGVS. ABSTRAK: Grid mikro digunakan sebagai unit kawalan yang disambungkan kepada grid kuasa, di mana jarak elektrikal antara sumber kuasa reaktif dan bebanan yang memerlukan kompensasi reaktif tidak terlalu besar. Dengan itu, kompensasi yang selaras dengan sumber reaktif perlu diimplimentasikan untuk mengelak kegagalan voltan pantas dengan menggunakan Grid Mikro Penstabil Voltan (Microgrid Voltage Stabilizer - MGVS). Penstabil ini sesuai digunakan untuk meningkatkan profil voltan dinamik dan telah diuji ke atas sistem mikro grid 21-bus IEEE. Untuk memastikan keupayaan penstabil ini, tiga sumber penjanaan agihan (distributed generation - DG) telah digunakan (dua sumber PV yang dikategorikan sebagai pengubah kuasa elektronik berdasarkan DG dan penjana diesel yang dikenali sebagai mesin segerak berasaskan DG). Mulanya, semua sumber dan alatan yang diperlukan, diilustrasikan. Kemudian, satu model penstabil kawalan bersama parameter yang sesuai dengan mikro grid yang dikemukakan. Ketakcukupan voltan dalam sistem merupakan input penstabil, isyarat keluaran penstabil kemudiannya dibahagikan antara kesemua DG agar ia dapat menyalurkan kuasa reaktif yang diperlukan. Profil voltan dinamik setiap bus dengan kehadiran MGV dan ketidakhadirannya dibandingkan dengan mengimplikasikan gangguan. Keputusan simulasi menggunakan MATLAB/SIMULINK menunjukkan bahawa profil voltan dinamik setiap bus meningkat pada kadar yang memuaskan dengan kehadiran MGVS
Estimation of Solar Radiation: An Empirical Model for Bangladesh
Get PDFThis study is carried out to compute empirically global, diffuse and direct solar radiation on a horizontal surface for the ten districts equally distributed all over Bangladesh (20o34΄and 26o34΄north latitude, 88o01΄ and 92o41΄east longitude) as well as to predict correlations for them. For this study, meteorological data for 28 years (between 1980 and 2007) is used which is collected from Bangladesh Meteorological Department. The global radiation in Bangladesh is found to be maximum in the month of April/May and minimum in the month of November/December in all the districts. The values of the correlation coefficients a, b, c, d, c', d', e, f, e' and f' for ten stations of Bangladesh are also evaluated. It is evident that, the values of the coefficient “a” vary from 0.2296 to 0.2569, while the coefficient “b” varies from 0.5112 to 0.5560. The over all mean deviations of the ten values of a and b are 0.2432±0.0136 and 0.5336±0.0224, respectively. The maximum and minimum values of other correlation coefficients c, d, c', d', e, f, e' and f' are (1.5695 and 1.4357), (-1.7210 and -1.9986), (0.4011 and 0.376), (-0.2072 and -0.2510), (-0.3811 and -0.5464), (1.946 and 1.6456), (-0.1206 and -0.1684) and (0.7984 and 0.7000) respectively. Their maximum variations due to location are (1.5022±0.0672), (-1.8598±0.1388), (0.3885±0.0125), (-0.2291±0.0219), (-0.4637±0.0826), (1.7958±0.1502), (-0.1445±0.0239) and (0.7492±0.0492) respectively. ABSTRAK: Kajian ini dibuat secara empirikal mengenai kadar penyebaran secara resapan, global dan langsung radiasi solar, keatas permukaan mendatar untuk sepuluh daerah di seluruh Bangladesh (20o34΄ dan 26o34΄ utara latitud, 88o01΄ dan longitud 92o41΄ timor) dan meramal korelasi mereka. Kajian ini menggunakan data meteorologi selama 28 tahun (antara 1980 dan 2007) yang dikutip dari Jabatan Meteorologi Bangladesh. Radiasi global maksima di Bangladesh adalah pada bulan April / Mei dan minima pada bulan November / Disember di semua daerah. Kajian dibuat mengenai nilai pekali korelasi a, b, c, d, c', d', e, f, e' dan f' bagi sepuluh stesen di Bangladesh. Nilai pekali "a" adalah antara 0.2296 dan 0.2569, manakala pekali "b" adalah antara 0.5112 dan 0.5560. Sisihan min keseluruhan bagi sepuluh nilai a dan b adalah 0.2432 ± 0.0136 dan 0.5336 ± 0.0224. Nilai maksima dan minima pekali korelasi lain c, d, c', d', e, f, e' dan f' adalah (1.5695 and 1.4357), (-1.7210 dan -1.9986), (0.4011 dan 0.376), (-0.2072 dan -0.2510), (-0.3811 dan -0.5464), (1.946 dan 1.6456), (-0.1206 dan -0.1684) dan (0.7984 dan 0.7000). Variasi maksima antara mereka disebabkan lokasi adalah (1.5022±0.0672), (-1.8598±0.1388), (0.3885±0.0125), (-0.2291±0.0219), (-0.4637±0.0826), (1.7958±0.1502), (-0.1445±0.0239) dan (0.7492±0.0492).KEYWORDS: Bangladesh; coefficient; correlation; radiation; sola
DISEASE DETECTION FROM FIELD SPECTROMETER DATA
Get PDFABSTRACT: Oil palm plants have been planted in large scale of areas. Ganoderma disease has been recognized and diagnosed in oil palm plants to infect almost half of the oil palm plants in Malaysia. To deal with this problem, the use of vegetation indices analysis on hyper spectral field data we will examine the ability of this data in discrimination between Ganoderma disease stages in oil palm plants which will be helpful in control the spread of the diseases. By using vegetation indices the oil palm plants could be classified into 1 (T1 healthy), 2 (T2 semi healthy) and 3 (T3 severe damage) plant classes accurately. The results showed that the best vegetation index is the Modified Red Edge Simple Ratio (MSR705) among the vegetation indices to discriminate between oil palm health stages. It was realized that the modification that was applied to the Modified Red Edge Simple Ratio (MSR705) index of Narrowband greenness VIs has been exhibited an acceptable results in differentiate between the oil palm plant stage 1 (T1 healthy) and stage 2 (T2 semi healthy). ABSTRAK: Tanaman kelapa sawit ditanam secara meluas. Penyakit ganoderma dikenali dan didiagnosikan menjangkiti hampir separuh tanaman kelapa sawit di Malaysia. Untuk mengawal penyakit ini daripada merebak, analisis indeks tanaman dijalankan ke atas data kawasan spektrum melampau di mana keupayaan data ini diuji dalam membezakan peringkat-peringkat penyakit Ganoderma terhadap tanaman kelapa sawit. Dengan menggunakan indeks tanaman, kelapa sawit dapat diklasifikasikan kepada 1 (T1 sihat), 2 (T2 separa sihat) dan 3 (T3 rosak); kelas tanaman dengan tepat. Keputusan menunjukkan indeks tanaman terbaik sebagai Modified Red Edge Simple Ratio (MSR705) yang merupakan indeks tanaman dalam membezakan peringkat kesihatan kelapa sawit. Adalah didapati pengubahsuaian terhadap indeks Modified Red Edge Simple Ratio (MSR705) yang juga indeks Jalur Sempit Hijau VI telah memberikan keputusan yang munasabah dalam membezakan peringkat tanaman kelapa sawit peringkat 1 (T1 sihat) dan peringkat 2 (T2 separa sihat)
ON CALCULATION OF MULTIPLE EIGENVALUES OF THE LINEAR OPERATOR-FUNCTION BY REDUCTION PSEUDO-PERTURBATION METHODS
Get PDFABSTRACT: In this article, methods of theory of bifurcations, applies to the problem of retaining of the approximately given multiple eigenvalues and their generalized eigenvectors. This approach allows the reduction of algebraic multiplicity of eigenvalue to one and transfers the problem to the similar one but with simple eigenvalue. The method of the false perturbation is used to construct iterative processes. ABSTRAK: Dalam artikel ini, kaedah teori bifurkasi diaplikasikan terhadap masalah untuk mengekalkan penghampiran pelbagai nilai eigen dan vektor eigen yang teritlak. Kaedah ini membenarkan pengurangan kegandaan aljabar nilai eigen kepada satu dan memindahkan permasalahan kepada yang hampir serupa tetapi dengan nilai eigen yang lebih mudah. Pengkaedahan usikan palsu digunakan untuk proses pelelaran
Biogas Digester with Simple Solar Heater
Get PDFABSTRACT: In this research work, the design, fabrication and investigation of a biogas digester with simple solar heater are presented. For the solar heater, a built-in reverse absorber type heater was used. The maximum temperature (50°C) inside the methane tank was taken as a main parameter for the design of the digester. Then, the energy balance equation for the case of a static mass of fluid being heated was used to model the process. The parameters of thermal insulation of the methane tank were also included in the calculations. The biogas digester consisted of a methane tank with built-in solar reverse absorber heater to harness the radiant solar energy for heating the slurry comprising of different organic wastes (dung, sewage, food wastes etc.). The methane tank was initially filled to 70% of its volume with organic wastes from the GIK institute’s sewage. The remaining volume was filled with sewage and cow dung from other sources. During a three month period (October-December, 2009) and another two month period (February-March, 2010), the digester was investigated. The effects of solar radiation on the absorber, the slurry’s temperature, and the ambient temperature were all measured during these investigations. It was found that using sewage only and sewage with cow dung in the slurry resulted in retention times of four and two weeks, respectively. The corresponding biogas produced was 0.4 m3 and 8.0 m3, respectively. Finally, this paper also elaborates on the upgradation of biogas through the removal of carbon dioxide, hydrogen sulphide and water vapour, and also the process of conversion of biogas energy into electric powerABSTRAK: Kajian ini membentangkan rekabentuk, fabrikasi dan penyelidikan tentang pencerna biogas dengan pemanas solar ringkas. Sebagai pemanas solar, ia dilengkapkan dengan penyerap pemanas beralik. Suhu maksimum(50oC) di dalam tangki metana telah diambil sebagai parameter utama rekabentuk pencerna. Dengan menggunakan persamaan tenaga seimbang untuk jisim statik cecair yang dipanaskan; parameter penebat haba tangki metana telah dikira. Pencerna biogas terdiri dari tangki metana yang dilengkapkan dengan penyerap pemanas beralik untuk menggunakan tenaga solar bagi memanaskan sluri yang disediakan dari bahan buangan organik yang berbeza (najis, sampah, sisa makanan,etc). Tangki metana telah diisi sehingga 70% isipadu buangan oraganik dari institut GIK, pertamanya adalah sampah dan keduanya adalah najis lembu. Pencerna telah dikaji bagi tempoh tiga bulan (Oktober-Disember, 2009) dan dua bulan (Februari-Mac, 2010). Kejadian radiasi solar terhadap penyerap, suhu sluri dan suhu ambien telah diukur. Didapati suhu penahanan adalah empat minggu dan dua minggu masing-masing dengan menggunakan sampah sahaja dan sampah dengan najis lembu, dan kuantiti biogas dihasilkan adalah masing-masing 0.4 m3 and 8.0 m3. Sebagai tambahan, skema peningkatan biogas untuk peranjakan karbon dioksida, hidrogen sulfida dan wap air dari biogas dan penukaran tenaga biogas kepada tenaga elektrik juga dibincangkan.KEYWORDS:  solar biogas; digester; methane tank; reverse absorber; built-in heater; solar energ
AN INVESTIGATION ON SOFT MAGNETIC AND NON-MAGNETIC MATERIALS UNDER LOW FREQUENCY FOR BIOMEDICAL SENSOR APPLICATION
Get PDFIn consequence of the recent development of magnetic sensors in biomedical sector, the investigation of magneticmaterials has been a contributing factor in application stage. This paper proposes a novel technique to investigate materials by obtaining unique distinctive impedance peaks with unique impedance values. A magneto-inductive sensoris used to measure the induction of magnetic and non-magnetic impedance peaks related to the change in permeability, thus characterizing the materials under low frequency
A PHILOSOPHICAL APPROACH TO ARTIFICIAL INTELLIGENCE AND ISLAMIC VALUES
Get PDFArtificial Intelligence has the potential to empower humans through enhanced learning and performance. But if this potential is to be realized and accepted, the ethical aspects as well as the technical must be addressed. Many engineers claim that AI will be smarter than human brains, including scientific creativity, general wisdom and social skills, so we must consider it an important factor for making decisions in our social life and especially in our Islamic societies. The most important challenges will be the quality of representing the Islamic values like piety, obedience, Halal and Haram, and etc in the form of semantics. In this paper, I want to emphasize on the role of Divine Islamic values in the application of AI and discuss it according to philosophy of AI and Islamic perspective.Keywords- Value, expert, Community Development, Artificial Intelligence, Superintelligence, Friendly Artificial Intelligenc