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Nowadays, Wireless Local Area Network (WLAN) become more popular due to its capability to carry high speed signal and it is cost saving. In this system, antenna plays a significant role in building effective communication between places at different location. Radial Line Slot Array Antenna (RLSA) has been designed and developed based on IEEE 802.11a standard in the frequency range of 572-5875MHz for WLAN system applications. Typically this system uses standard parabolic dish antenna. However the use of these antennas has some disadvantages such as aperture blockage. To overcome this drawback, a new antenna design is proposed and investigated. Therefore, this research was conducted in order to design and develop an antenna with aesthetic, low cost, high performance, durable and flat. The development of linearly polarized RLSA antenna wi...
Rice husk ash (RHA) consisting more than 90% of amorphous silica obtained under controlled burning of rice husk was directly used in the synthesis of ferrierite type-zeolite. The synthesis was performed under hydrothermal condition in the presence of different organic templates, oxide compositions and at various crystallization periods. Solid products obtained from the synthesis were characterized by XRD, FTIR, 29Si MAS NMR, N2 (g) adsorption and SEM techniques. Results showed that pure ferrierite can be formed from the initial molar oxide ratios in the range of 1.31 – 1.5 Na2O : Al2O3 : 10 – 30 SiO2 : 4 – 10.0 template : 410 H2O with only pyrrolidine (Py) as the organic template. In general, quartz was obtained at higher SiO2/Al2O3 and lower Py/Al2O3 ratios. The crystal phase changes from ferrierite to analcime and lastly to qua...
Mesoporous molecular sieve Al-MCM-41 with Si/Al=20 and polymethacrylic acid (PMAA) were used as supports for the immobilization of bulky iron(III)- 5,10,15,20-tetra-(4-pyridyl) porphyrin (Fe-TPyP). Metalloporphyrin of Fe(III) was encapsulated inside the mesopores of the ordered structure of Al-MCM-41 by sequential synthesis of Fe-TPyP via treatment of FeCl3 with 5,10,15,20-tetra-(4- pyridyl) porphyrin (TPyP), followed by encapsulation of Fe-TPyP. Fe-TPyP complexes were also successfully encapsulated into PMAA by polymerizing methacrylic acid (MAA) with a cross-linker around the Fe-TPyP complexes. The materials obtained were characterized by X-ray Diffraction (XRD), Fourier Transform Infrared (FTIR), Ultraviolet Visible Diffuse Reflectance (UV-Vis DR), Electron Spin Resonance (ESR), Luminescence and 13C CP/MAS NMR spectroscopies, Thermo...
Proses industrialisasi saat ini tidak hanya terjadi di kawasan perkotaan saja. Daerah-daerah pinggiran dengan lingkup kabupaten seringkali berlomba-lomba dalam memajukan perindustrian di wilayahnya. Salah satu upaya yang seringkali dilakukan pemerintah daerah yaitu menciptakan iklim investasi melalui berbagai kebijakan probisnis.
“Dualistik” merupakan istilah yang tepat untuk menggambarkan kondisi umum kota-kota di Indonesia saat ini. Istilah dualistik itu sendiri memiliki konotasi pada terjadinya pertemuan dua kondisi atau sifat yang berbeda. Pada aspek sosial-ekonomi masyarakat kota tercipta kegiatan yang bersifat formal dan informal (Sujarto dalam Widjayanti: 2000). Sektor formal diwadahi dalam ruang formal sesuai dengan yang telah diatur dalam RDTRK, sedangkan sektor informal belum terakomodasi dalam wadah serta aturan kebijakan pengelolaan yang rinci. Sektor informal merupakan suatu fenomena umum yang tak dapat terhindarkan di wilayah perkotaan
Sempitnya lapangan pekerjaan di sektor formal, mendorong masyarakat untuk beralih ke sektor informal demi kelangsungan hidupnya, salah satunya dengan berprofesi sebagai Pedagang Kaki Lima (PKL). Menurut McGee dan Yeung (1977:25), PKL mempunyai pengertian yang sama dengan ”hawkers”, yang didefinisikan sebagai orang-orang yang menjajakan barang dan jasa untuk dijual di tempat yang merupakan ruang untuk kepentingan umum, terutama di pinggir jalan dan trotoar.
Recently, owing to environmental and economic considerations, interest in utilizing biomass for the production of energy and chemicals is increasing. Palm oil shell wastes are one of the main agriculture waste in Malaysia. Pyrolysis is one of the most promising thermochemical techniques for recovering energy from biomass. Pyrolysis of oil-palm shell waste was first carried out using thermogravimetric analysis (TGA). The effects of heating rate on the pyrolytic properties were investigated. The kinetic parameters have also been determined using integral method. This paper also describes the experimental results from a bench-scale circulating fluidized-bed (CFB) test rig, installed at SIRIM Berhad, Shah Alam, suitable for gasification and combustion experiments using different biomass materials. The purpose of the tests was to i...
In this paper we present a 2 transmit 1 receive (1 Tx : 1 Rx) adaptive spatial mode (ASM) of space-time (ST) and space-frequency (SF) orthogonal frequency division multiplexing (OFDM). At low signal to noise ratio (SNR) we employ ST-OFDM and switch to SF-OFDM at a certain SNR threshold. We determine this threshold from the intersection of individual performance curves. Results show a gain of 9 dB (at a bit error rate of 10-3) is achieved by employing adaptive spatial mode compared to a fixed ST-OFDM, almost 6 dB to fixed SF-OFDM, 4 dB to Coded ST-OFDM and 2 dB to a fixed coded SF-OFDM, at a delay spread of 700 ns.
This book was translated from English to Malay. The early section of Chapter 1 (Introduction) highlights the need of state-of-the-art technology in order to reduce capital expenditure and operational cost when conducting deep sea drilling. It also outlines the importance of tertiary recovery in order to increase ultimate oil recovery
This book was translated from English to Malay. The early section of Chapter 1 describes the gas composition from gas wells and from oil wells. Other topics covered are phase behaviour, equation of state, etc.
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