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"Sea Clutter: Scattering, the K Distribution and Radar Performance gives an authoritative account of our current understanding of radar sea clutter. The authors pay particular attention to the compound K distribution model, which they have developed over the past 20 years. Evidence supporting this model, including a detailed review of the calculation of EM scattering by the sea surface, its statistical formulation, and practical application to the specification, design and evaluation of radar systems are all discussed. The calculation of the performance of practical radar systems is presented in sufficient detail for the reader to be able to tackle related problems with confidence.This book should be invaluable to specialist radar engineers and academic researchers, and of considerable interest to the wider applied physics and mathematics communities."

"Dalam beberapa dekade, akuisisi MT biasanya dilakukan dalam bentuk profil lintasan 2D. Namun pemodelan inversi 2D memiliki kekurangan terutama terkait dengan keberadaan struktur yang lebih kompleks 3D strike . Ambiguitas ini termasuk dalam pemilihan mode yang digunakan TE atau TM . Ambiguitas ini dapat menyebabkan kesalahan dalam interpretasi. Ambiguitas data seperti yang terjadi pada inversi 2D dapat diatasi dengan menggunakan program inversi 3D.Inversi MT 3D dilakukan dengan menggunakan dengan menggunakan perangkat lunak Mod3DEM dengan algoritma NLCG Non Linear Conjugate Gradient dan sudah memasukkan faktor topografi. Data input yang digunakan dalam inversi 3D adalah sebanyak 92 titik, dengan range frekuensi 320 ndash; 0.01 Hz. Pengolahan data menggunakan rotasi principal axis dan koreksi statik menggunakan data TDEM. Selain itu, data pendukung lain yang digunakan dalam penelitian ini adalah data geokimia dan data geologi. Berdasarkan hasil inversi 3D MT, Karakteristik sistem geothermal lapangan ldquo;INARA rdquo; terlihat dengan batuan penudung memiliki resestivitas rendah 80 ohm-m. Top of reservoir berada di ketinggian 500 meter dari MSL dengan heat source berada di bawah puncak gunung WL. Dari hasil perhitungan geothermometer silika dan diagram entalphy-Cloride mixing, diperoleh temperatur reservoir daerah prospek panas bumi ldquo;INARA rdquo; adalah 200 oC. Sedangkan berdasarkan geothermometer CO2, temperatur reservoir daerah prospek panas bumi ldquo;INARA rdquo; adalah 260 oC dan masuk dalam kategori high temperature >225 oC.

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Within a few decades, MT acquisition is used to be done in a 2D track profile. However 2D inversion modeling has its drawbacks mainly related to the existence of the existence of complex structures 3D strike . This will bring ambiguity that can lead to errors in interpretation. Data ambiguity as occurs in 2D inversion can be overcome by using 3D inversion program.The software used in MT 3D Inversion is Mod3DEM with NLCG Non Linear Conjugate Gradient algorithm and has included topography factor. The input data used in 3D inversion is 92 points, with frequency range 320 0.01 Hz. The data processing used principal axis rotation and static corrected by TDEM data. The other supporting data used in this study are geochemical data and geological data.

Based on the 3D MT inversion results, the characteristics of the INARA geothermal field system are seen with low residence rocks 80 ohm m. Top of the reservoir is at an altitude of 500 meters from MSL with the heat source is under the peak of WL mountain. From the calculation of silica geothermometer and entalphy cloride mixing diagram, it is known the reservoir temperature of geothermal prospect region INARA is 200 oC. While based on CO2 geothermometer, the reservoir temperature of geothermal prospect region INARA is 260 oC and included in high temperature 225 oC."

"Petir merupakan fenomena alam yang sering ditemui dalam kehidupan sehari-hari dan tidak dapat dihindari. Sambaran petir pada suatu bangunan memiliki dampak yang merusak baik bagi mahluk hidup, bangunan, maupun peralatan listrik. Sistem proteksi petir pada suatu bangunan diperlukan untuk mengurangi resiko kerusakan akibat sambaran petir. Sitem proteksi petir terbagi menjadi dua jenis yaitu sistem proteksi petir eksternal dan internal. Sistem proteksi internal berfungsi untuk melindungi peralatan listrik yang berada di dalam gedung. Berdasarkan perhitungan menggunakan beberapa standar proteksi petir yaitu IEC 62305, SNI 03-7015-2004, NFPA 780, dan PUIL 2011, Gedung i-CELL membutuhkan sistem proteksi petir dengan tingkat proteksi petir I. Sistem proteksi petir tingkat I memiliki arus petir puncak sebesar 200 kA. Arus petir puncak tersebut dapat mengalir pada panel distribusi dengan nilai arus yang bervariasi mulai dari 0,132 kA hingga 33,3 kA. Oleh karena itu dibutuhkan koordinasi surge protection device berupa circuit breaker dan arrester pada panel distribusi. Selain itu, terdapat medan elektromagnetik akibat induksi pada tulangan struktur ataupun akibat sambaran petir tidak langsung. ZPP1 pada Gedung i-CELL dapat mereduksi 20% medan elektromagnetik dari ZP 0. Ikatan penyama potensial dibutuhkan pada peralatan yang dapat menyimpan muatan akibat induksi medan elektromagnetik untuk menghindari sparks antar peralatan. Peralatan pada Gedung i-CELL yang tidak dapat dipasang IPP harus diberi jarak sebesar 6.32 meter dari konduktor penyalur. Pembagian zona proteksi petir (ZPP) pada Gedung i-CELL terbagi menjadi ZPP 1 dan ZPP 2.

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Lightning is a natural phenomena that occur frequently in our daily life. Lightning strike on a building can cause several damage to living creatures, structures, and electronic equipments. Lightning protection system is needed to reduce the damage risk from the lightning strike. There are two kind of lighting protection system, external protection system and internal protection system. The purpose of lightning internal system is to protect electronic equipments inside the building. Based on several standards such as IEC 62305, SNI 03-7015-2004, and NFPA 780, and PUIL 2011, i-CELL building need a level I lightning protection system. Peak current at level I lightning protection system can reach up to 200 kA. These current can flow through the distribution panel with various current level from 0.132 kA to 33.3 kA. Therefore, coordination of surge protection device such as circuit breaker and arrester are needed in the distribution panel. There are also an electromagnetic fields cause by induction from the structure and indirect lightning strike. The LPZ 1 in i-CELL building can reduce up to 20% of the electromagnetic field. Equipments that can have electric charge from electromagnetic induction must be connected to an equipotential bonding to prevent sparks. For equipments that can’t be connected to an equipotential bonding must have 6.32 meter of safety distance from down-condcutor. Lightning protection zone in i-CELL building are divided into LPZ 1 dan LPZ 2."

"A weather- influenced Maxwell's electromagnetic model for lightning activities has been considered. Three governing equations were stated for further analysis. The charge dynamics, lightning branches and atmospheric factors were analyzed. The model was validated by analyzing ground data from the Davis-Pro weather station. The data collected was targeted for the month with the highest lightning activity. It was discovered that lightning occurs at the upper pressure level (under certain conditions that are stated in the thesis) while the low pressure level initiates an updraft, i.e. air rises and condenses into a cumulonimbus cloud. These findings present the keys to considering a lightning system as a source of alternative energy."

"Kehadiran peralatan memasak yang semakin canggih dan inovatif seperti kompor induksi telah mengubah cara memasak dengan memberikan tingkat efisiensi yang tinggi. Kompor induksi juga merupakan terobosan dalam mengurangi emisi karbon dan menjadikannya pilihan penting dalam upaya konservasi energi. Penggunaan kompor induksi di masyarakat masih menghadapi beberapa kendala seperti harga yang relatif masih tinggi, konsumsi daya yang signifikan, dan kebutuhan akan wadah memasak khusus. Selain itu, perkembangan teknologi kompor induksi dapat menghasilkan emisi elektromagnetik berupa emisi konduksi (conducted emission). Conducted emission merupakan gangguan elektromagnetik yang ditimbulkan oleh perangkat elektronik melalui penghantar (konduktor) yang dapat dinterpretasikan sebagai arus noise yang merambat pada jalur konduksi dan berpotensi mengganggu peralatan elektronik lainnya melalui sumber tegangan. Dalam jaringan listrik yang sama, conducted emission yang ditimbulkan kompor induksi juga dapat mengganggu sinyal data yang menggunakan Power Line Carrier (PLC) pada frekuensi 30-500 kHz. Penelitian ini bertujuan untuk menemukan dampak karakteristik pola emisi gelombang elektromagnetik yaitu emisi konduksi (conducted emission) yang dihasilkan oleh kompor induksi. Fokus utama adalah pada emisi yang dikonduksi, yang dapat mempengaruhi kinerja perangkat elektronik tersebut. Hasil penelitian terkait karakteristik nilai conducted emission dari kompor induksi ini diharapkan agar perangkat rumah tangga ini semakin aman serta nyaman digunakan oleh masyarakat dan dapat memberikan referensi untuk pengembangan teknologi kompor induksi selanjutnya. Metode pengujian dilakukan pada 4 (empat) merek kompor induksi C, A, M dan P dalam berbagai kondisi operasi dan mode memasak baik secara individual maupun diperasikan secara bersamaan di rentang frekuensi 9 KHz-30 MHz melalui pengujian Electromagnetic Compatibility (EMC). Parameter yang diukur adalah nilai Quasi Peak (QP), sesuai dengan standar CISPR 14.1:2020. Berdasarkan pengukuran di rentang frekuensi 9 kHz-30 MHz kondisi individual diperoleh bahwa sebagian kompor induksi yang dipergunakan dalam penelitian ini berada di atas nilai ambang batas yang dipersyaratkan dalam CISPR 14.1:2020. Berdasarkan pengukuran dengan kondisi kompor induksi dioperasikan secara simultan, tingkat conducted emission mengalami penurunan dan terdapat disturbance pada frekuensi baru di luar frekuensi disturbance pada saat kondisi individual.

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The presence of increasingly sophisticated and innovative cooking equipment, such as induction cookers, has transformed the way we cook by providing a high level of efficiency. Induction cookers also represent a breakthrough in reducing carbon emissions, making them a crucial choice in energy conservation efforts. However, the use of induction cookers in society still faces several challenges, such as relatively high prices, significant power consumption, and the need for special cooking vessels. Furthermore, the development of induction stove technology can result in electromagnetic emissions known as conducted emissions. Conducted emissions are electromagnetic disturbances caused by electronic devices through conductors, interpreted as noise currents propagating on conductive paths and potentially disrupting other electronic equipment through voltage sources. In the same electrical network, the conducted emissions generated by induction cooker can also interfere with data signals using Power Line Carrier (PLC) at frequencies of 30-500 kHz. The aim of this research is to identify the impact of the characteristics of electromagnetic wave emission patterns, specifically conducted emissions, generated by induction cookers. The main focus is on the conducted emissions that can affect the performance of electronic devices. The research results related to the characteristics of the conducted emission values from these induction cookers are expected to contribute to the safety and comfort of household devices, providing reference points for the further development of induction stove technology. Testing was conducted on four (4) brands of induction cooker, labeled as C, A, M, and P, under various operating conditions and cooking modes, both individually and simultaneously, across the frequency range of 9 KHz-30 MHz through Electromagnetic Compatibility (EMC) testing. The measured parameter was the Quasi Peak (QP) value, following the CISPR 14.1:2020 standard. Based on measurements in the frequency range of 9 kHz-30 MHz under individual conditions, it was found that some induction cookers used in this study exceeded the required threshold values in CISPR 14.1:2020. However, when measuring induction cooker operated simultaneously, the level of conducted emissions decreased, and there were disturbances at new frequencies outside the disturbance frequencies observed under individual conditions."

"Electromagnetic theory offers fascination and challenge from both a physical and a mathematical perspective. This monograph contains the newest results on the use of electromagnetic probes to interrogate dielectric material structures for material properties and geometry. This volume systematically exploits interface phenomena, the electrodynamics of material responses, and time dependent interrogating signals in an integrated manner. The authors begin with basic electromagnetics, such as Maxwell's equations, and present modeling, theory, and computational results. The book's strengths include a clear discussion of materials properties from the electromagnetic point of view, a careful formulation of the imaging problems addressed, rigorous treatment of mathematical issues, and useful illustration of computational methods and results. While confined to internal vision in one-dimensional settings, this volume will stimulate further developments in internal vision to include two- and three-dimensional interior assessments. It is an excellent and robust source of applied mathematics and engineering research challenges for the future. Imaging technology stands to benefit much from this research on low energy electromagnetic radiation. The use of electromagnetic pulses interacting with specially placed reflective surfaces, whether solid or acoustic, is a new dimension that will substantively impact medical imaging, subsoil investigation, and structure evaluation."

"This book systematically explains the fundamentals of system-level electromagnetic compatibility and introduces the basic concept of system-level electromagnetic compatibility quantification design. The topics covered include the critical technologies in the top-down quantification design of electromagnetic compatibility, quantification design of system-level electromagnetic compatibility, evaluation methods and application examples, quality control and application examples of electromagnetic compatibility development process, and real-world engineering example analysis of electromagnetic compatibility.The book proposes a top-down system-level electromagnetic compatibility quantification design method and is the first book to describe in detail how to quantitatively evaluate and predict system-level electromagnetic compatibility performance. It includes abundant engineering examples and experimental data demonstrating the usage and results of the top-down quantification design methods of system-level electromagnetic compatibility.It enables readers to obtain a thorough understanding of the theory and methods of system-level electromagnetic compatibility quantification design as well as the methodologies for engineering practice."

"This book discusses the problem of electromagnetic wave excitation in spatial regions with spherical boundaries and the accurate mathematical modeling based on numerical and analytical methods to significantly reduce the time required for developing new antenna devices. It particularly focuses on elements and systems on mobile objects of complex shape that are made of new technological materials. The experimental development of such devices and systems is an extremely time-consuming, lengthy, and expensive process. The book is intended for senior and postgraduate students and researchers working in the fields of radiophysics, radio engineering and antenna design. The authors assume that readers understand the basics of vector and tensor analysis, as well as the general theory of electrodynamics. The original results presented can be directly used in the development of spherical antennas and antenna systems for the mobile objects."

"ABSTRAKSuatu teknik yang relatip baru untuk mensimulasikan open boundary telah diterapkan pada penyelesaian persoalan elektromagnet tiga dimensi dengan menggunakan metode elemen hingga berbasis elemen tetrahedral vektor. Teknik ini disebut juga teknik PML karena menggunakan material PML atau Perfectly Matched Layer. Material PML ini mempunyai sifat anisotropis pada arah diagonal. Material PML bersifat loss-y, sehingga gelombang elektromagnet yang berasal dari udara babas akan diteruskan dan diredam secara eksponensial. Secara teoritis, koefisien refleksi pada perbatasan antara medium udara dengan medium PML adalah nol. Karakteristik medium PML dinyatakan dalam parameter α dan β. Konstanta α menentukan panjang gelombang pada medium PML, sedangkan menentukan laju peredarnan gelombang elektromagnet yang diteruskan. Teknik PML ini diterapkan pada open waveguide persegi ernpat.Pemodelan open boundary dilakukan dengan menggunakan kode program EMAP, yang merupakan kode pemodelan elemen hingga tiga dimensi. Kode program pemodelan open boundary ini dibuat dalam bahasa C. Konfrgurasi masukan yang diberikan ke kode program berupa file berbentuk teks atau numerik, dan menghasilkan keluaran dengan format yang sama dengan masukan. Keluaran dari kode program merupakan sekumpulan data numerik berupa titik-titik koordinat di seluruh domain komputasi dan distribusi medan listriknya. Perangkat lunak Jandel Sigma Plot 3.0 digunakan untuk memvisualisasikan data numerik Sedangkan, paket program pengolah data Microsoft Excell digunakan agar formal keluaran yang dihasilkan oleh kode program sesuai dengan format perangkat lunak Sigma Plot 3.0.Eksperimen numerik dilakukan untuk mengetahul distribusi medan listrik di dalam waveguide persegi empat pada berbagai ketebalan lapisan PML. Selanjutnya hasil eksperimen tersebut tersebut dibandingkan dengan penyelesalan secara analitis. Mode eksitasi yang digunakan adalah mode dominan TE10 dan TE20. Hasil perhitungan numerik tersebut menunjukan bahwa nilai koefisien refleksi berbanding terbalik dengan ketebalan lapisan PML. Semakin tebal lapisan PML maka nilai koefsien refleksi pada perbatasan antara medium udara dengan medium PML akan semakin kecil. Pada ketebalan lapisan antara 4 s/d 16 PML diperoleh rugi-rugi antara 4.00 db s/d 33.73 db. Ketebalan lapisan PML dinyatakan dalam jumlah elemen. Eksperimen numerik lalnnya dilakukan untuk menghilung pengaruh konstanta α dan β dari medium PML terhadap distribusi medan listrik pada domain komputasi.

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ABSTRACT

A newly used technique offree space simulation has been implemented for solving unbounded electromagnetics problems with the finite element method based on tetrahedral edge or vector element. This technique uses a layer of diagonally anisotropic material referred to as a PML. The PML layers are lossy, so the outgoing waves from the computation domain will be absorbed, and exponentially atenuated. The PML itself can be characterized by a and ,B, where adetermines the wave length in the anisotropic absorber and /7 determines the rate of decay of the transmitted wave. Eventhough, the material properties can be chosen such that the interface between the absorbing material and free space is reflection-less, but a numerical reflection error must be taken into account. An open rectangular waveguide is used as a model to investigate the PML technique.

The modelling is carried out using EMAP, which is a three dimensional finite element modelling code that can be used to simulate open region, and written in the C programming language. The code reads the input configuration in as an ASCII text file, and provides output in the same form. Output from the code consist of a listing of the node coordinates and the electric field strength at each node. These numerical data are not easily understood, so a post processing is needed to manipulate them into a graphical output. To do this, the data are rearranged by the spreadsheet Microsoft Excel , and then plotted by dandel Sigma Plot 3.0 for a visualization.

A number of experiments is carried out to investigate the electric field distribution in the computation domain. The results show that after a few layers the electromagnetic wave is exponentially attenuated through the PML material. Then, the numerical results are compared to the analytical solution. These numerical results may be important in determining the number of PML layers needed to obtain a given accuracy. It can be seen that the reflection is reciprocal of the number of layers. The reflection coefficient is decreased by increasing the layer thickness. A thickness of 4 to 16 PML layers have loss in the range of 4.00 db to 33.73 dh. The layer thicknes itse f is represented in term of a number of elements. Another experiment is also done to investigate the electric field distribution in the computation domain with varied in ca and A It is concluded that the PMLs work well to model an open rectangular waveguide."