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"This book highlights the origin of low external quantum efficiency for deep ultraviolet light-emitting diodes (DUV LEDs). In addition, it puts forward solutions for increasing the internal quantum efficiency and the light extraction efficiency of DUV LEDs. The book chiefly concentrates on approaches that can be used to improve the crystalline quality, increase carrier injection, reduce the polarization-induced electric field within multiple quantum wells, suppress the TM polarization emission, and enhance the light escape from the semiconductor layer. It also demonstrates insightful device physics for DUV LEDs, which will greatly benefit the optoelectronic community."

"This book presents innovative ideas and technical contributions in the area of metasurfaces and antenna technologies. On the one hand, it presents an effective method to analyze metasurfaces constituted by metallic texture with certain geometries. It shows how this method can be applied to the design of metasurface (MTS) antennas for deep space communications and other planar microwave devices. On the other hand, the book reports on a general methodology developed for analyzing flat devices realized by using modulated MTSs, which opens new design possibilities for a large number of microwave devices based on the manipulation of SWs. Finally, a novel approach of reconfigurability, which is based on a class of checkerboard MTS, is explored. All in all, this book covers important insights and significant results on the emerging topic of metasurfaces, from theoretical and computational aspects to experiments."

"This book develops the analytical theory of perfectly conducting and lossy metal, circular, round-wire loop antennas and nano-scaled rings from the radio frequency (RF) regime through infrared and the optical region. It does so from an antenna theory perspective. It is the first time that all of the historical material found in the literature has appeared in one place. It includes, particularly, material that has appeared in the literature only in the last decade and some new material that has not yet been published. The book derives the input impedance, resonances and anti-resonances, the RLC circuit model representation, and radiation patterns not only of closed loops and rings, but also of loops and rings loaded randomly and multiply with resistive and reactive impedances. Every derivation is compared with simulations run in Microwave Studio (MWS). It looks carefully at the physical response of loop antennas and nano-rings coupled to a source at one point in the periphery and at such rings illuminated by a plane wave arriving from every different direction with the E-field in all polarizations. The book ends with a brief look at polygonal loops, two dimensional arrays of nano-rings, and Yagi-Uda arrays."

"This book discusses the recent research developments of various passive microwave circuits on silicon substrate and demonstrated operations catering for multiple frequency bands. It covers the design, modelling, process fabrication and characterization aspects with practical examples. The book will be of use to researchers and engineers working in the field of RF or microwave engineering, who can use the techniques and approaches effectively without having to refer to multiple sources. "

"Material penyerap gelombang mikro telah banyak diteliti sebelumnya, terutama mengarah ke material paduan berbahan polimer. Dalam penelitian ini polimer konduktif yang digunakan adalah polianilin (PANi) yang dipadukan dengan paduan material barium heksaferit substitusi ion Ti dan Mn dan kobalt ferit (BHFTM/CFO), dimana material tersebut mempunyai sifat magnetik, karena pada dasarnya material yang bisa digunakan sebagai penyerap gelombang mikro adalah material yang mempunyai sifat dielektrik dan magnetik. Dengan kata lain suatu material dapat dikatan penyerap gelombang mikro jika memiliki sifat permitivitas, permeabilitas, total magnetisasi, dan resistivitas yang tinggi. PANi disintesa dengan menggunakan metoda polimerisasi oksidasi, sedangkan BHFTM dan CFO disintesa menggunakan metoda pemaduan mekanik dan dilakukan sonikasi untuk memperkecil ukuran partikel. Paduan PANi/BHFTM/CFO disintesa dengan cara menambahkan material pengisi ke dalam matriks PANi dengan rasio 20:80, 50:50, dan 80:20 (% berat) kemudian dilakukan pengepresan dengan tekanan sebesar 5 ton selama 10 detik sebanyak 2 kali. Karakterisasi nanokomposit diuji dengan menggunakan spektrofotometer FTIR untuk polimer, X-ray Diffraction (XRD), Scanning Electron Microscope (SEM), Conductivity Meter (metoda four point probe), Particle Size Analyzer (PSA), Permagraph, dan Vector Network Analyzer (VNA). Dengan adanya substitusi ion pada material barium hexaferrit maka terdapat perubahan baik pada sifat magnetisasi dan penyerapan gelombang mikro. Karakterisasi XRD menunjukkan pola difraksi BHFTM tidak berbeda dengan BHF hanya terjadi pergeseran puncak. Sedangkan hasil karakterisasi SEM menunjukkan terjadi perpaduan antara BHFTM dan CFO. Hasil karakterisasi absorpsi dengan VNA menunjukkan adanya serapan pada komposit PHMM 2080 yaitu -20 dB pada frekuensi 12,8 GHz dimana komposit yang digunakan menggunkaan polianilin hasil doping (PANi-HCl) dan magnetik dalam multi kristalit partikel dengan rasio fraksi massa komponen polimer:magnetik sebesar 20:80. Perubahan ukuran partikel menjadi nano kristalit partikel menghasilkan serapan sebesar -19,08 db pada frekuensi 12,75 GHz (komposit PEMN 8020 atau komposit PANi-EB:Magnetik nano partikel dengan rasio fraksi massa 80:20).

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Microwave absorber materials have been widely studied, especially leading to polymeric based composite materials. In this study, conductive polymers used are polyaniline (PANi) combined with a blend of material barium heksaferit substitution ion Ti and Mn and cobalt ferrite (BHFTM/CFO), wherein the material has magnetic properties, because basically materials that can be used as a microwave absorber if a material that has dielectric and magnetic properties. In other words the absorbent material can used absorbent if it has properties of permittivity, permeability, total magnetization and resistivity low. PANi synthesized by using the method polymerization oxidation while BHFTM and CFO were synthesized using a mechanical alloying synthesis method then sonication process for reduce particle size. PANi/BHFTM/CFO composite synthesized by adding a filler material into the matrix PANi with a ratio of 20:80, 50:50, and 80:20 (% by weight) and then do the pressing with a pressure of 5 tons for 10 seconds twice. The characterization of nanocomposite tested using FTIR spectrophotometer for the polymer, X-ray Diffraction (XRD), Scanning Electron Microscope (SEM), Conductivity Meter (method four-point probe), Particle Size Analyzer (PSA), Permagraph, and Vector Network Analyzer (VNA). With the substitution of ions in the barium hexaferrite material there is a change in both the magnetization and microwave absorption properties. XRD characterization shows BHFTM diffraction pattern is not different from BHF only peak shift occurs. While the results of SEM characterization shows a combination between BHFTM and CFO. The characterization results of absorption by VNA showed absorption at 2080 PHMM composite is -20 dB at 12.8 GHz frequency where composites are used menggunkaan polyaniline doping results (PANi-HCl) and magnetic particles in a multi crystallites with the ratio of the mass fraction of the polymer components: magnetic amounted 20:80. The change crystallite size particles into nano particles produce uptake of -19.08 db at a frequency of 12.75 GHz (8020 PEMN composites or composite PANi-EB:Magnetic nano-particles with mass fraction ratio of 80:20)."

"Kurkumin merupakan senyawa polifenol yang banyak terkandung pada tanaman kunyit (Curcuma longa L.). Kurkumin terbukti memiliki aktivitas biologis seperti antibakteri, antikanker, antioksidan, antidiabetes, dan antiinflamasi. Metode microwave-ultrasound-assisted extraction (MUAE) merupakan metode ekstraksi hijau yang dikembangkan untuk meningkatkan yield kurkumin dan meningkatkan produktivitas ekstraksi. Penelitian ini bertujuan untuk meningkatkan yield kurkumin dan meningkatkan produktivitas ekstraksi dibanding dengan metode ultrasound-assisted extraction (UAE) dengan menambahkan microwave pre-treatment menggunakan natural deep eutectic solvents (NADES) sebagai pelarut yang ramah lingkungan. Kondisi operasi seperti waktu microwave pre-treatment dan waktu ekstraksi dioptimasi dengan menggunakan response surface methodology (RSM). Kondisi optimum diperoleh pada waktu microwave pre-treatment 60 detik dan waktu ekstraksi 20 menit dengan produktivitas ekstraksi tertinggi. Metode MUAE menghasilkan yield kurkumin 9,96% lebih tinggi dengan peningkatan produktivitas sebesar 2,32 kali lipat dibandingkan metode UAE. Kurkumin hasil ekstrak diseparasi dengan metode yang ramah lingkungan menggunakan air sebagai anti pelarut untuk memisahkan kurkumin dari NADES. Proses separasi kurkumin yang dilakukan, menghasilkan recovery sebesar 12,50%-54,03% dan meningkatkan kemurnian kurkumin dari 0,11%-0,31% pada ekstrak menjadi 13,79%-24,14% pada padatan kurkumin.

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Curcumin is a polyphenolic compound that is widely contained in turmeric plants (Curcuma longa L.). Curcumin is proven to have biological activities such as antibacterial, anticancer, antioxidant, antidiabetic, and anti-inflammatory. The microwave-ultrasound-assisted extraction (MUAE) method is a green extraction method developed to increase curcumin yield and improve extraction productivity. This study aims to increase curcumin yield and increase extraction productivity compared to the ultrasound-assisted extraction (UAE) method by adding microwave pre-treatment using natural deep eutectic solvents (NADES) as an environmentally friendly solvent. Operating conditions such as microwave pre-treatment time and extraction time were optimized using response surface methodology (RSM). The optimum conditions were obtained at a microwave pre-treatment time of 60 seconds and an extraction time of 20 minutes with the highest extraction productivity. The MUAE method produced 9.96% higher curcumin yield with an increase in productivity of 2.32 times compared to the UAE method. The extracted curcumin was separated by an environmentally friendly method using water as an anti-solvent to separate curcumin from NADES. The curcumin separation process resulted in recovery of 12.50%-54.03% and increased the purity of curcumin from 0.11%-0.31% in the extract to 13.79%-24.14% in curcumin solids."

"The expanded 4th edition of this classic optics text is aimed at those wishing to apply their knowledge of optics to engineering problems, and provides a sound introduction to the basic principles of optics for engineering students. It describes fundamental material including Fourier optics, diffraction theory, geometrical optics, and lenses, and goes on to cover important topics such as optical signal processing, holography, tomography, optical communication, electro- and acousto-optic devices, integrated optics, 3D imaging and optical distance measurement."

"This book discusses low power techniques for millimeter wave transmitter IC. Considerations for the front-end design are followed by several implementation examples in the 60GHz band in CMOS down to 28nm technology. Additionally, the design and implementation details of digitally-modulated millimeter wave polar transmitters are presented."

"Strontium hexaferrite dengan komposisi nominal Sr0.6Fe,-<,..,jMn,TiyO, (x =0, y=; x = 0.4, y= 0.6; x = 0.5, y = 0.5; x = 0.6, y =0.4) disintesa dengan reaksi keadaan padat. Empat komponen serbnk BaCO,, SrCO,, Fe,O,, MnCO,, dan TiO, dicampur menggunakan High Energy Milling selama 10 jam dan disinterring pada 1050'C dalam tekanan atrnosfer selama 15 jam dan pendinginan eli tungku pemanas. X-ray diffraction (XRD), scanning electron microscope (SEM), energy dispersive spectroscopy (EDS), vibrating sample magnetometer (VSM) dan network analyzer digunakan untuk analisa struktur, sifat elektomagnetik dan penyerapan gelombang. Hasil memperlihatkan bahwa identifikasi fasa dengan penghalusan pola difrkasi XRD diperoleh fasa tunggal untuk substitusi Mn-Ti terhadap Sr0.6Fe,o, dengan x ~ y dan multi fasa terbentuk untnk x " y. Analsis mikrostrnktur dengan SEM menunjukkan variasi partikel adalah 2 - 5 um. Evaluasi terhadap karakteristik magnetik mengindikasikan bahwa terjadi penurunan koersifitas dengan kenaikan substitusi ion Mn2+ dan Ti4+ tetapi penurunan yang signifikan diperoleh terhadap saturasi magntetisasi pada substitusi Mn dan Ti dengan x :t: y. Penelitian saat ini menunjukkan penyerapan gelombang, reflection dan transmission dan juga reflection loss pada rentang frekuensi 7-16 GHz. Dilaporkan juga performansi penyerapan pada substitusi Mn dan Tipada strontium hexaferrite.

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Strontium hexaferrite with nominal compositions Sr0.6Fe,-{"':Y~xTiy03 (x ~ 0, y o=Q; x ~ 0.4, y ~ 0.6; x ~ 0.5, y ~ 0.5; x ~0.6, y ~ 0.4) have been synthesized by solid state reaction. The four components powder were BaCO,, S!CO,, Fe,O,, MnCO,, and Ti02 mixed with High Energy Milling for 10 hours and sintered at I 050'C in the air at atmosphere pressure for 15 hour and furnace cooling. X-ray diffraction (XRD), scanning electron microscope (SEM), energy dispersive spectroscopy (EDS), resonance vibrating sample magnetometer (R· VSM) and vector network analyzer were used to analyze its structure, electromagnetic and microwave absorption properties. The result showed that, phase identification by refinement results ofXRD pattern confirmed single phase was obtained for Mn-Ti substituted Sr0.6Fe20, with x ~ y and multiphase formed for x" y. The microstructure analyses by SEM showed that the varied particle sizes of 2 -- 5 ~-tm. Evaluation on the magnetic characteristic indicated that coercivity decreased as the number ofMn2"~" and Ti +ions increased but significant decrease in saturation magnetization obtained for Mn and Ti substitution with x ::1:- y. Present investigation demonstrates that microwave absorber. reflection and transmission as well as reflection loss in the frequency range 7-16 GHz were derived Absorption performance ofMn and Ti substituted strontium hexaferrite are also reported."

"This book focuses on the modeling, optimization, and applications of 5G green mobile communication networks, aimed at improving energy efficiency and spectrum utilization in 5G systems. It offers a balance between theoretical analysis and engineering practice, providing in-depth studies of a number of major topics, such as energy consumption models, optimization, system design, implementation, and performance evaluation. It also discusses four aspects of green communication in detail: cellular networks, resource management, wireless transmissions and multi-media communications. Further, this unique book comprehensively and systematically discusses green optimization in wireless mobile communications. As such it is a valuable resource for researchers, engineers, and graduate students in various fields, including telecommunications engineering, electrical and electronic engineering, and computer engineering, particularly those interested in green communications."