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"Research and development in the terahertz portion of the electromagnetic spectrum has expanded very rapidly during the past fifteen years due to major advances in sources, detectors and instrumentation. Many scientists and engineers are entering the field and this volume offers a comprehensive and integrated treatment of all aspects of terahertz technology. The three authors, who have been active researchers in this region over a number of years, have designed Terahertz Techniques to be both a general introduction to the subject and a definitive reference resource for all those involved in this exciting research area."

"Telah diketahui bahwa bumi memiliki medan magnet yang dihasilkan oleh proses self-excited dynamo. Model dinamo kinematika dapat menggambarkan bagaimana suatu self-excited dynamo dibangkitkan dari interaksi antara aliran fluida dengan medan magnet. Namun, terdapat satu teorema anti dinamo yang mengatakan bahwa aliran yang planar tidak dapat menghasilkan medan magnet, yang dikenal dengan Teorema Aliran Planar (TAP) yang diberikan oleh Zel'dovich (1957).Bachtiar, Ivers dan James (BIJ, 2006) telah membuktikan bahwa bukti untuk TAP tidak berlaku untuk ruang konduktor dengan volume hingga. Mereka berhasil menemukan satu model numerik yang mengindikasikan kemungkinan adanya suatu model dinamo kinematika yang memiliki aliran planar. Namun, hasil pengujian numeriknya hanya memiliki konvergensi sekitar 10 %.Penelitian ini adalah kelanjutan dari penelitian Bachtiar (2009) yang mencoba menemukan model dinamo kinematika baru yang dapat diplanarkan, untuk mendukung hasil BIJ. Salah satunya adalah model quasiPAS yang diperoleh dengan cara memodifikasi nilai akar yang digunakan pada model dinamo kinematika Pekeris, Accad, Shkoller (PAS). Penulis melakukan pengujian numerik terhadap model quasiPAS dengan menggunakan 36 model yang berbeda.

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Its known that the Earth has magnetic field that is generated by selfexcited dynamo process. Kinematic dynamo model describes how a self-excited dynamo generated from the interaction between the conducting fluids and magnetic field. However, there is an anti-dynamo theorem which says that a planar flow can not maintain magnetic field, known as Planar Velocity Theorem (PVT) that was given by Zel'dovich (1957).Bachtiar, Ivers and James (BIJ, 2006) has shown that Zeldovich's proof for PVT does not apply when the conducting fluids occupies a finite volume. They found a numerical model which indicate that there is a kinematic dynamo model with planar flow. However, their numerical results have only about 10% of convergency level.This thesis is continuation of Bachtiar's research (2009) who tried to obtain a new kinematic dynamo models that can be planarized, to support the result of BIJ . One is quasiPAS models which obtained by modifying the root used in the kinematic dynamo model Pekeris, Accad, Shkoller (PAS). The author performed a numerical test of quasiPAS model with 36 different models."

"Electromagnetic vibration energy harvesting devices introduces an optimization approach which is applied to determine optimal dimensions of the components (magnet, coil and back iron). Eight different commonly applied coupling architectures are investigated. The results show that correct dimensions are of great significance for maximizing the efficiency of the energy conversion. A comparison yields the architectures with the best output performance capability which should be preferably employed in applications. A prototype development is used to demonstrate how the optimization calculations can be integrated into the design?flow. Electromagnetic vibration energy harvesting devices targets the designer of electromagnetic vibration transducers who wishes to have a greater in-depth understanding for maximizing the output performance."

"This paper reports on the magnetic properties and electromagnetic characterization of La0.8Ba0.2FexMn½(1-x)Ti½(1-x)O3 (x = 0.1–0.8). The La0.8Ba0.2FexMn½(1-x)Ti½(1-x)O3 (x = 0.1–0.8) materials were prepared using a mechanical alloying method. All the materials were made of analytical grade precursors of BaCO3, Fe2O3, MnCO3, TiO2, and La2O3, which were blended and mechanically milled in a planetary ball mill for 10h. The milled powders were compacted and subsequently sintered at 1000°C for 5h. All the sintered samples showed a fully crystalline structure, as confirmed using an X-ray diffractometer. It is shown that all samples consisted of LaMnO3 based as the major phase with the highest mass fraction up to 99% found in samples with x < 0.3. The mass fraction of main phase in doped samples decreased in samples with x > 0.3. The hysteresis loop derived from magnetic properties measurement confirmed the present of hard magnetic BaFe12O19 phase in all La0.8Ba0.2FexMn½(1-x)Ti½(1-x)O3 (x = 0.1–0.8) samples. The results of the electromagnetic wave absorption indicated that there were three absorption peaks of ~9 dB, ~8 dB, and ~23.5 dB, respectively, at respective frequencies of 9.9 GHz, 12.0 GHz, and 14.1 GHz. After calculations of reflection loss formula, the electromagnetic wave absorption was found to reach 95% at the highest peak frequency of 14.1 GHz with a sample thickness of around 1.5 mm. Thus, this study successfully synthesized a single phase of La0.8Ba0.2FexMn½(1-x)Ti½(1-x)O3 (x = 0.1–0.8) for the electromagnetic waves absorber material application."