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"This book provides the basis of the design of rotating AC machines. The first chapter puts the emphasis on the air gap magnetomotive force (MMF) of Rotating AC machines and the second chapter deals with the formulation of the rotating fields that could be generated considering different technique. The third chapter of this book focuses on the arrangement of the armature winding of fractional-slot concentrated winding permanent magnet synchronous machines, which is achieved considering the star of slots approach.Each topic is explained by case studies that show how to implement the theory into real-world design of DC machines."

"Berbagai produk teknologi berupa alat elektronik yang dipergunakan sehari-hari ternyata mampu menghasilkan medan elektromagnetik dengan frekuensi samgat rendah (extremely low frequency) yang dapat mengganggu kesehatan sistem organ manusia, salah satunya sistem reproduksi. Beberapa penelitian telah membuktikan gangguan pada sistem reproduksi pria dapat memicu terhambatnya proses spermatogenesis sehingga menurunkan produksi sperma. Untuk itu, dilakukan penelitian terhadap salah satu sel pada proses spermatogenesis, yakni sel spermatosit 1 pakiten, dan dilihat pengaruh pajanan elektromagnetik terhadap jumlah sel tersebut. Jenis penelitian ini adalah eksperimental dengan melakukan pemajanan pada mencit jantan Strain Webster generasi pertama (F1), kedua (F2), dan ketiga (F3) dengan tegangan 0 kV (kontrol), 3 kV, 4 kV, dan 5 kV. Hasil penelitian ini menunjukkan adanya penurunan jumlah sel spermatosit 1 pakiten pada pemajanan kelompok mencit 3 kV, 4 kV, 5 kV dibandingkan dengan kelompok kontrol (p < 0,05). Pemajanan dengan tegangan 3 kV tidak memiliki efek akumulatif pada generasi pertama, kedua, dan ketiga (p > 0,05). Pemajanan dengan tegangan 4 kV hanya memiliki efek akumulatif pada generasi pertama ke generasi kedua. Pemajanan dengan tegangan 5 kV memiliki efek kumulatif pada generasi kedua ke generasi ketiga. Selain itu, pemajanan dengan tegangan 3 kV, 4 kV, 5 kV berkorelasi sebanding dengan penurunan jumlah sel. Dengan demikian, pajanan medan elektromagnetik ELF berpengaruh terhadap penurunan jumlah sel spermatosit 1 pakiten dan memiliki efek akumulatif pada generasinya.

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Many high tech-product electronic devices that is used daily capable on producing extremely low frequency electromagnetic field that could disturb human organ, one of which is reproduction system. Many research has showed that disturbance in male reproduction system could cause impeded spermatogenesis process so as decrease sperm production. This research was done to one of the cell related to spermatogenesis process, which is the spermatocyte 1 in its pachytene stage. Consequently, the effect of the electromagnetic exposure to the quantity of the cell was observed. This experimental research was done by exposing first generation (F1), second generation (F2), and third generation (F3) male Webster strain albino house mouse with 0 kV (control), 3 kV, 4 kV, and 5 kV voltage.

The result show a decline in pachytene spermatocyte 1 at the 3 kV, 4kV, 5kV exposure group than the control group (p<0,05). The exposure of more than 3kV did not have accumulative effect on first, second, and third generation (p>0,05). Exposing with 4 kV only has an accumulative effect in the first and second generation. Exposing with 5 kV showed an accumulative effect on second to third generation. Moreover, exposing with 3kV, 4kV, 5kV correlated consecutively with propotional decline in cell quantity. Therefore, ELF electromagnetic field exposure has an effect to decline in pachytene spermatocyte 1 quantity and have an accumulative effect to each generation."

"ABSTRAKPenelitian ini didasarkan pada terjadinya distorsi torsi pada generator magnet permanen saat generator tersebut berputar yang menimbulkan getaran dan derau dan dapat menyebabkan berkurangnya usia mesin, terutama pada penggunaan penggerak langsung. Salah satu cara untuk mengurangi distorsi torsi berupa riak torsi adalah dengan mengubah rancangan konvensional dari struktur stator dan rotor mesin tersebut. Dengan demikian, metode untuk mengurangi riak torsi yang dilakukan dalam penelitian ini adalah dengan memotong ujung/tepi magnet berbentuk busur yang dinamakan magnet bertepi busur atau edge-rounded magnet ERM . Adapun tujuan dari penelitian ini adalah mengembangkan model torsi elektromagnetik dari generator magnet permanen inset dengan ERM sehingga didapatkan riak torsi minimal. Maka diterapkanlah metode tersebut pada generator magnet permanen inset 24 alur 16 kutub dan dibandingkan dengan model dasar tanpa ERM untuk mendapatkan model dengan riak minimal. Perhitungan riak torsi dengan metode torsi rata-rata mendapatkan bahwa riak terendah dicapai oleh generator magnet permanen dengan ERM 2,2 mm yaitu sebesar 2,59 , jauh lebih rendah dibandingkan model dasar 29,87 . Metode least square juga mendapatkan hasil yang sama, model ERM 2,2 mm mempunyai riak terendah sebesar 0,18 dibandingkan model dasar 46,28 . Dengan demikian, modifikasi edge-rounded magnet berhasil memperkecil riak torsi pada generator magnet permanen inset. Dengan riak torsi yang jauh lebih kecil, maka getaran pada generator tersebut juga akan ikut berkurang, walaupun hasil perhitungan mendapatkan bahwa daya keluaran dan efisiensi ERM 2,2 mm hanya sedikit lebih tinggi dibandingkan model dasar. Daya keluaran generator magnet permanen inset dengan ERM 2,2 adalah 1881,487 W, lebih tinggi 8,54 W dari model dasar 1872,948 W , sedangkan efisiensi ERM 2,2 mm adalah 94,07 hanya naik 1,42 dari model dasar 93,65 .

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ABSTRACTThis study is based on the distortion of torque on a permanent magnet generator when the generator is rotating which causes vibration and noise, and can be responsible to reduce the engine life, particularly in the use of direct drive. One alternative to reduce torque distortion in the form of torque ripple is to change the established design of the stator and the rotor structure of the machine. Therefore, the method for reducing the torque ripple carried out in this study is by cutting off an arc shaped magnetic edge called edge rounded magnet ERM . The objective of this study is to develop the model of electromagnetic torque from inset permanent magnet generator with ERM, to obtain the minimum torque ripple. Then applied the method to a permanent magnet generator inset 24 slots 16 poles and compared with the basic model without ERM to get the model with minimal ripple. The computation of torque ripple with the average torque method found that the lowest ripple was carried out by a inset permanent magnet generator with ERM 2.2 mm of 2.59 , much lower than the base model 29.87 . The least square method also got the same result, the ERM 2.2 mm model takes the lowest ripple of 0.18 being comparable to the basic model 46.28 . Therefore, edge rounded magnetic modification strongly minimizes the torque ripple on the inset permanent magnet generator. With a substantial less torque ripple, the vibrations on the generator will similarly decrease, although the calculation results show that the output power and efficiency of ERM 2.2 mm are merely slightly higher than the base model. The output power of permanent magnet generator with ERM 2.2 mm is 1881.487 W, 8.54 W higher than the base model 1872.948 W , while the efficiency of ERM 2.2 mm is 94.07 only up 1.42 from the base model 93.65 ."

"This book is both a course book and a monograph. The first chapter briefly introduces the history, background and technology of EPM. In the second chapter, the concept of transport phenomena is concisely introduced and in the third chapter the essential part of magnetohydrodynamics is transcribed and readers are shown that the concept of transport phenomena does not only apply to heat, mass and momentum, but also magnetic field. The fourth chapter describes electromagnetic processing of electrically conductive materials such as electromagnetic levitation, mixing, brake, and etc., which are caused by the Lorentz force. The fifth chapter treats magnetic processing of organic and non-organic materials such as magnetic levitation, crystal orientation, structural alignment and etc., which are induced by the magnetization force. This part is a new academic field named magneto-science, which focuses on the development of super-conducting magnets."

"This textbook is intended for a course in electromagnetism for upper undergraduate and graduate students. The main concepts and laws of classical macroscopic electrodynamics and initial information about generalized laws of modern electromagnetics are discussed, explaining some paradoxes of the modern theory. The reader then gets acquainted with electrodynamics methods of field analysis on the basis of wave equation solution. Emission physics are considered using an example of the Huygens-Fresnel-Kirchhoff canonic principle. The representation about strict electrodynamics task statement on the base of Maxwell equations, boundary conditions, emission conditions and the condition on the edge is given. Different classes of approximate boundary conditions are presented, which essentially simplify understanding of process physics. The canonic Fresnel functions are given and their generalization on the case of anisotropic impedance. The free waves in closed waveguides and in strip-slotted and edge-dielectric transmission lines are described. A large number of Mathcad programs for illustration of field patterns and its properties in different guiding structures are provided. The material is organized for self-study as well as classroom use."