Design of planar dielectric resonator antenna array at 28 GHz

This article presents a planar array of rectangular Dielectric Resonator Antenna operating for 28 GHz applications. The proposed antenna is formed through two stages of designs which are a single element and planar array. It is made up from a ceramic material with a dielectric constant of 10 and mounted on RT/Duroid 5880 with a relative permittivity of 2.2 and a thickness of 0.254 mm. A prospective study using three different configurations of three by three planar array is done in order to obtain the best performance in terms of bandwidth, gain, and cost reduction. Besides that, this study is also conducted for a beam steering capability of each configuration. Finally, the best configuration is proposed for 5G application

Training needs assessment in Malaysia: Exercise held at Kuala Lampur and Kota Bharu from 13th October 1989

Training / Irrigation / Evaluation / Malaysia

Kesan penggunaan koswer multimedia animasi visual terhadap pencapaian pelajar dalam mata pelajaran matematik

Ramai pelajar yang bermasalah dalam topik Pelan dan Dongakan. Ini kerana pelajar sukar untuk membayangkan objek yang tersembunyi melalui proses pengajaran dan pembelajaran (P&P) secara konvensional. Penyelidik telah membangunkan satu koswer multimedia animasi visual dalam topik Pelan dan Dongakan dengan menerapkan kesemua elemen-elemen yang dapat membantu meningkatkan kemahiran visual iaitu elemen animasi, video, audio, grafik dan teks. Seterusnya, kajian kuasi eksperimental ini turut dijalankan bertujuan untuk mengetahui kesan penggunaan koswer multimedia animasi visual terhadap pencapaian pelajar bagi mata pelajaran Matematik di sekolah menengah. Ujian Pra dan Ujian Pos digunakan untuk melihat perbezaan pencapaian yang signifikan selepas menggunakan koswer multimedia animasi visual yang menggunakan teori Kognitif Visual Wiley. Responden yang terlibat dalam kajian ini ialah seramai 40 orang pelajar Tingkatan Lima yang dibahagikan kepada dua kumpulan iaitu kumpulan rawatan dan kumpulan kawalan yang dipilih daripada sebuah sekolah di daerah Batu Pahat, Johor. Hasil analisis menunjukkan peningkatan skor min markah bagi pelajar kumpulan rawatan. Hasil analisis ujian-t (paired-sample-t-test) membuktikan bahawa wujudnya perbezaan skor min markah yang signifikan di antara markah ujian pra dan markah ujian pos bagi kumpulan rawatan. Oleh itu, terdapat perbezaan yang signifikan di antara skor min markah ujian pra dan ujian pos bagi pelajar kumpulan rawatan selepas menggunakan koswer multimedia animasi visual. Manakala instrumen soal selidik yang digunakan untuk melihat tahap penerimaan pelajar selepas menggunakan koswer multimedia animasi visual berdasarkan tiga aspek iaitu aspek isi kandungan, aspek interaksi dan aspek persembahan telah memeperolehi skor min yang tinggi bagi ketiga-tiga aspek tersebut. Dapatan kajian ini menggambarkan penggunaan koswer multimedia animasi visual dapat membantu meningkatkan pencapaian Matematik di dalam bilik darjah terutama yang tidak melibatkan pengiraan

A novel green antenna phase-shift system with data acquisition boards

A novel green phase shifter system is proposed in this research. The system is developed by a combination of reconfigurable beam steering antennas and data acquisition (DAQ) boards. A combination of two reconfigurable beam steering antennas, located side-by-side, forms a spatial configuration structure with a fabricated ‘green’ element plank of rice husk placed in between. The concept of a spatial configuration technique has been ‘mutated’ by shifting the structure of spiral feed line and aperture slots of first beam steering antenna by as much as 45 ◦ . The PIN diode switches connected to the DAQ boards enable the intelligent capability of the spatial antennas. The activation of certain degree radiation patterns of either the first beam steering antenna or the second beam steering antenna depends on the memory of the DAQ boards — Beam Manager. When an intruder comes from the cardinal angles of 0◦/ 360◦, 90◦, 180◦, or 270◦, its range and angles’ location will be automatically detected by the first antenna through the output ports of the 1st DAQ: P1.0, P1.1, P1.2, and P1.3. The second antenna is then activated by the output ports of the 2nd DAQ: P2.0 up to P2.3, to adaptively maneuver the beam towards four different ordinal directions of 45◦, 135◦, 225◦, and 315◦

Effect of Spiral Split Ring Resonator (S-SRR)structure on Truncated Pyramidal Microwave Absorber Design

This paper discusses on the effect of the spiral split ring resonator on the truncated pyramidal microwave absorber. Split ring resonator (SRR) structure can potentially be incorporated onto the truncated pyramidal microwave absorber to increase the reflection loss performance. There are many ways to increase the pyramidal microwave absorber performance. The ways are focusing the new hybrid shapes, using high carbon material, and adding the left handed material structure on the pyramid microwave absorber. Left handed material or metamaterial is an artificial material that does not exist in the real nature like FR4, Taconic, Rogers or RT Duriod.There are many types of left handed material that had been used by several researchers such as split ring resonator (SRR), and photonic band gap (PBG), electromagnetic band gap (EBG) and artificial magnetic conductor (AMC). In this research, spiral split ring resonator (S-SRR) is used to increase the microwave absorber performance. It has the potential to increase the reflection loss or 811 results of the microwave absorber at the several frequencies

Pembangunan kemahiran penyelesaian masalah berlandaskan projek origami

Kemahiran penyelesaian masalah merupakan salah satu kaedah pengajaran yang digunakan di dalam kelas. Ia merupakan satu proses pengajaran dan pembelajaran yang berasaskan pengalaman dan memerlukan pelajar berfikir secara aktif. Tujuan kajian ini dilakukan untuk mendapatkan persepsi pelajar terhadap kemahiran menyelesaikan masalah tugasan folio dengan berlandaskan seni lipatan kertas. Ini bagi membantu pelajar meningkatkan elemen kemahiran penyelesaian masalah seperti mengenalpasti masalah, merancang dan melaksanakan strategi serta dapat menyelesaikan apa jua sebarang masalah. Kajian ini bersifat kuantitatif dengan reka bentuk eks pos fakto yang menggunakan instrumen soal selidik secara tinjauan awal dan tinjauan akhir seterusnya dianalisis menggunakan SPSS versi 21. Setiap keputusan dapatan ditunjukkan dalam bentuk min, peratus dan ujian T. Sampel kajian adalah terdiri 30 orang pelajar tahun 2 semester 3 jurusan Pemesinan Industri. Dapatan keseluruhan min sebelum aktiviti bengkel ialah 3.43 manakala selepas aktiviti bengkel min ialah 4.03. Keputusan hasil kajian ini mendapati kemahiran penyelesaian masalah selepas menjalani aktiviti origami, berada pada tahap yang tinggi. Oleh yang demikian, cadangan penyelidik untuk mengemukakan kemahiran penyelesaian masalah berlandaskan kaedah origami di terima baik dan bagi membantu pihak tertentu terutamanya Pihak Kolej Vokasional Melaka Tengah dalam menyelesaikan masalah tugasan folio di kalangan pelaja

Grip force measurement of soft- Actuated finger exoskeleton

Over recent years, the reseach in the field of soft actuation has been extensively increased for achieving more complex motion path with smooth, high flexible movement and high generated force at minimum operating pressure. This paper presents the study on gripping force capability of soft actuators applied on glove-type finger exoskeleton, developed in motivation to assist individuals having weak finger gripping ability in their rehabilitation exercise towards hand function restoration. The exoskeleton utilizes five cylindrical shaped pneumatic bending actuators developed in the lab, which use fiber reinforcement as a cause of bending motion that drive finger’s flexion movement. Four right-handed healthy volunteers simulated paralysis participated in the study. At 200kPa safe operating pressure, the soft exoskeleton worn by the subjects demonstrates the ability to provide adequate grip force. The grip force generated from exoskeleton worn on passive right hand is 4.66 ± 0.2 N and 3.61± 0.2 N from passive left hand, both higher than the minimum grip forces measured to hold the Hand Dynamometer of 240 g. It shows good potential to be used as a finger rehabilitation assist device

Surface Conditions Analysis of Polymeric Insulators Under Contamination Effects

A good polymer insulator can maintain the hydrophobic surface properties. However, polymer insulator is exposed to the environment which may lead to the deposition of rain water or factory oil. Oil is categorized as hydrophobic while water has a hydrophilic feature which when deposit on the insulator surface, it may affect the performance of insulator. Therefroe, this paper studies the effect of water and oil contamination on current density and space charge distribution along 15 kV polymeric insulators particularly ethylene propylene-diene monomer (EPDM) and silicone rubber (SiR). A three-dimensional model of polymeric insulator was designed using a finite element software to evaluate the current density and space charge distribution while the experimental works was conducted in the laboratory to measure the charge distribution only. The results reveal that both current density and charge distribution is affected depend on the conductivity of contamination conditions. Both results extracted from simulation and experimental is in agreement where the EPDM insulator have higher amplitude of charge compared to SiR insulator

High Dimensional Modulation and MIMO Techniques for Access Networks

Exploration of advanced modulation formats and multiplexing techniques for next generation optical access networks are of interest as promising solutions for delivering multiple services to end-users. This thesis addresses this from two different angles: high dimensionality carrierless amplitudephase (CAP) and multiple-input multiple-output (MIMO) radio-over-fiber (RoF) systems. High dimensionality CAP modulation has been investigated in optical fiber systems. In this project we conducted the first experimental demonstration of 3 and 4 dimensional CAP with bit rates up to 10 Gb/s. These results indicate the potentiality of supporting multiple users with converged services. At the same time, orthogonal division multiple access (ODMA) systems for multiple possible dimensions of CAP modulation has been demonstrated for user and service allocation in wavelength division multiplexing (WDM) optical access network. 2 x 2 MIMO RoF employing orthogonal frequency division multiplexing (OFDM) with 5.6 GHz RoF signaling over all-vertical cavity surface emitting lasers (VCSEL) WDM passive optical networks (PONs). We have employed polarization division multiplexing (PDM) to further increase the capacity per wavelength of the femto-cell network. Bit rate up to 1.59 Gbps with fiber-wireless transmission over 1 m air distance is demonstrated. The results presented in this thesis demonstrate the feasibility of high dimensionality CAP in increasing the number of dimensions and their potentially to be utilized for multiple service allocation to different users. MIMO multiplexing techniques with OFDM provides the scalability in increasing spectral effciency and bit rates for RoF systems. High dimensional CAP and MIMO multiplexing techniques are two promising solutions for supporting wired and hybrid wired-wireless access networks

Mitochondrial barcodes of dragonflies and damselflies originated from Taman Negara Endau Rompin, Johor, Malaysia

Dragonflies and damselflies (Odonates) are important biological indicators in freshwater ecosystems. However, identification among Odonates is often challenging due to their similar morphological features. Therefore, the incorporation of morphological identification by taxonomists and validation using mitochondrial barcodes such as cytochrome c oxidase subunit I (COI) can be a more reliable approach to enhance the accuracy in species identification. In this study, four COI barcodes for Malaysian dragonflies (Neurothemis fluctuans) and damselflies (Neurobasis chinensis, Aristocypha fenestrella and Sundacypha petiolata) were generated. Three of the generated barcodes (D2 COI, D4 COI and D5 COI) supported the species identified by taxonomists meanwhile D3 COI deduced that the damselfly species was misidentified due to the very similar morphology between the same genus of damselfly. All of the COI barcodes are now available in the GenBank with the accession numbers of MT266926.1 (D2 COI), MT266925.1 (D3 COI), MT269676.1 (D4 COI) and MT266924.1 (D5 COI)