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"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."

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Pertanian 4.0 yang merupakan masa depan teknologi pertanian melambangkan revolusi dalam sektor pertanian melalui integrasi teknologi canggih seperti Internet of Things (IoT), pertanian presisi, dan masih banyak lagi. Salah satu metode untuk melibatkan implementasi IoT generasi mendatang dalam pengisian energi proaktif dan jaringan nirkabel generasi mendatang adalah pemanenan energi Frekuensi Radio (RF). Ini adalah proses menyerap energi dari RF dan mengubahnya menjadi listrik. Sebagai alat pemanen energi, digunakan rectenna (penyearah + antena), yang terdiri dari antena penerima, matching network, penyearah RF ke DC, elemen penyimpanan, dan beban. Penelitian ini mengusulkan rangkaian penyearah RF ke DC dengan frekuensi operasi 920 MHz. Berdasarkan hasil simulasi, rangkaian yang dirancang memiliki tegangan keluaran sebesar 3.3 V, arus keluaran sebesar 2.2 mA, dan tingkat efisiensi sebesar 73.31%. Rangkaian ini dibuat dalam sebuah PCB dengan dimensi 4 x 2.4 cm

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Agriculture 4.0, which is the future of agricultural technology, symbolizes a revolution in farming through the integration of advanced technologies such as the Internet of Things (IoT), precision agriculture, and many more. One method for involving the next-generation IoT implementation in proactive energy replenishment and next-generation wireless network is Radio Frequency (RF) energy harvesting. It is the process of absorbing energy from the RF and turns into electricity. As a tool for energy harvesting, a rectenna (rectifier + antenna) is used, which consists of a receiver antenna, matching network, RF-to-DC Rectifier, storage element, and a load. This research proposes an RF-to-DC Rectifier circuit with an operating frequency of 920 MHz. According to simulation results, the designed circuit has an output voltage of 3.3 V, an output current of 2.2 mA, and an efficiency level of 73.31%. This circuit was constructed in a PCB with a 4 x 2.4 cm dimension.

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"This book presents a comprehensive introduction to design sensitivity analysis theory as applied to electromagnetic systems. It treats the subject in a unified manner, providing numerical methods and design examples. The specific focus is on continuum design sensitivity analysis, which offers significant advantages over discrete design sensitivity methods. Continuum design sensitivity formulas are derived from the material derivative in continuum mechanics and the variational form of the governing equation. Continuum sensitivity analysis is applied to Maxwell equations of electrostatic, magnetostatic and eddy-current systems, and then the sensitivity formulas for each system are derived in a closed form; an integration along the design interface.The book also introduces the recent breakthrough of the topology optimization method, which is accomplished by coupling the level set method and continuum design sensitivity. This topology optimization method enhances the possibility of the global minimum with minimised computational time, and in addition the evolving shapes during the iterative design process are easily captured in the level set equation. Moreover, since the optimization algorithm is transformed into a well-known transient analysis algorithm for differential equations, its numerical implementation becomes very simple and convenient.Despite the complex derivation processes and mathematical expressions, the obtained sensitivity formulas are very straightforward for numerical implementation. This book provides detailed explanation of the background theory and the derivation process, which will help readers understand the design method and will set the foundation for advanced research in the future."

"Alternative energy, nowadays, becomes more necessary than fossil fuels which might be destructing and polluting the earth’s environment. Wind can be one of the most cheap, secure, environment friendly and reliable energy supplies. Building Integrated Wind Turbine (BIWT) is becoming increasingly common as a green building icon and new method of assessing optimal building energy. However, to employ BIWT, it is important to design the building shape and swept area carefully to increase wind velocity. Some of numerous design forms of BIWT will be explained in this paper using CFD (Computational Fluid Dynamics) analysis to find the most effective BIWT design in urban area. This paper will focus on the maximum wind velocity which passes the swept area to get maximum wind power. The result shows that, building energy can be optimized through aerodynamic building design to get the maximum wind power for building energy consumption."

"Tujuan dari penelitian ini adalah untuk mengembangkan sistem transduser dual transverse pada Ultrasonic Vibration Assisted Microforming (UVAM). Perancangan sistem transduser didasarkan pada dua gagasan terkait getaran yakni longitudinal dan transversal. Setiap sistem menggunakan transduser piezoelektrik Langevin, yang masing-masing dapat menciptakan getaran ultrasonik dengan amplitudo rendah. Pada gagasan longitudinal, getaran longitudinal yang dihasilkan oleh transduser diteruskan melalui sumbu yang sama menuju benda kerja. Sedangkan pada gagasan transversal, getaran longitudinal yang dihasilkan oleh dua transduser dalam fase yang sama diubah oleh sonotrode block berpori menjadi getaran dalam arah normal dengan permukaan benda kerja. Proses optimalisasi desain sistem transduser UVAM dilakukan dengan simulasi modal menggunakan metode Finite Element Analysis (FEA). Hasil analisis simulasi menunjukkan bahwa sistem transduser dual transverse dengan gagasan transversal memiliki frekuensi kerja yang lebih optimum dibandingkan gagasan lainnya, yakni sebesar 31,3 kHz dan memiliki amplitudo di permukaan dies pada sumbu normal sebesar 6,32 μm. Pada penelitian ini juga dilakukan validasi sistem transduser yang telah dikembangkan melalui uji amplitudo terhadap variasi getaran ultrasonik. Hasil dari skripsi ini adalah sistem transduser dual tansverse UVAM beserta microforming tool.

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The purpose of this study is to develop a dual transverse transducer system for Ultrasonic Vibration Assisted Microforming (UVAM). The design of the transducer system is based on two ideas related to vibration, namely longitudinal and transverse. Each system uses Langevin piezoelectric transducers, each of which can create low-amplitude ultrasonic vibrations. In the longitudinal idea, the longitudinal vibration generated by the transducer is transmitted through the same axis toward the workpiece. Whereas in the transverse idea, the longitudinal vibrations generated by two transducers in the same phase are converted by the porous block sonotrode into vibrations in the direction normal to the surface of the workpiece. The process of UVAM transducer system design optimization was done by modal simulation using Finite Element Analysis (FEA) method. The simulated analysis result shows that the transducer system with the transverse concept has a more optimum working frequency than the other ideas, which is 31,3 kHz and has an estimated total displacement on the normal axis of 6,32 µm. This study also validated the transducer system that had been developed by testing the amplitude with ultrasonic vibrations variation. The results of this thesis is dual transverse  UVAM transducer systems and microforming tool."

"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."