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"A significant part of the book is devoted to introducing the formal theory—a description of polarization and of nuclear reactions with polarized particles. The remainder of the text describes the physical basis of methods and devices necessary to perform experiments with polarized particles and to measure polarization and polarization effects in nuclear reactions. The book concludes with a brief review of modern applications in medicine and fusion energy research. For reasons of conciseness and of the pedagogical aims of this volume, examples are mainly taken from low-energy installations such as tandem Van de Graaff laboratories, although the emphasis of present research is shifting to medium- and high-energy nuclear physics. Consequently, this volume is restricted to describing non-relativistic processes and focuses on the energy range from astrophysical energies (a few keV) to tens of MeV. It is further restricted to polarimetry of hadronic particles."

"Penelitian ini mengksploitasi sifat komplementer dari set combinatorial Cyclic Difference Set (CDS) dan set bilangan ganjil dan genap guna memperoleh susunan interleaved untuk peningkatan utilisasi ruangan aperture antena susun linier. Penambahan elemen secara simetris terhadap titik awal dengan mengikuti taper yang berbeda menghindari tumpang tindih antarelemen antena sekaligus meningkatkan keluwesan penyesuaian terhadap ketersediaan ruangan kargo kendaraan peluncur satelit komunikasi. Konversi taper amplitudo menjadi taper jarak dari elemen antena yang ditambahkan dilakukan melalui prinsip equal illumination area dengan tingkat  ketepatan yang dicapai melalui minimisasi weighted mean squared eror. Penggunaan taper yang berbeda menjamin tidak adanya tumpang tindih antarelemen antena susun. Penggunaan elemen antena yang berbeda memungkinkan dibangunnya antena susun linier dengan sorot ganda terpolarisasi linier dan sorot ganda terpolarisasi ganda melingkar. Peletakan elemen antena susun secara simetri menjaga kemurnian polarisasi sehingga memungkinkan penyorotan area pelayanan yang overlap tanpa saling mengganggu. Kedua antena susun yang disintesa yaitu Faktor Array Complementary Improved Interleaved CDS Array  dan Faktor Array Complementary Improved Alternate Interleaved Array. Keduanya bebas grating lobe  dan  dicatu dengan amplitudo yang seragam sehingga menampilkan efisiensi konversi arus searah ke gelombang radio yang tinggi dan menampilkan keandalan sistem pada aplikasinya di satelit komunikasi.

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The study exploited complementary properties of the combinatorial set Cyclic Difference Set (CDS) and sets odd and even numbers to obtain an interleaved arrangement for improved aperture room utilization on linear stacking antennas. The addition of elements symmetrically to the origin by following a different taper avoids overlap between antenna elements while increasing the flexibility of adjustment to the availability of the cargo satellite of the communication air launchers.

The amplitude taper conversion to the distance taper of the additional elements were done through the principle of the equal illumination area with a precision level achieved through the minimization of weighted mean squared error. The use of different tapers guarantees the absence of overlapping collilers between the stacking antenna elements. The use of different antenna elements allows the construction of a linear stacking antenna with a double of linearly polarized beams and double circular polarization beams. The symmetry of the stacking antenna element maintains the polarization purity allowing for the beam of overlapping service areas without interferering each other.

The two interleaved array antennas were the antenna arrays of the Array Factor Complementary Improved Interleaved CDS Array and Array Factor Complementary Improved Alternate Interleaved Array. Both of the mentioned arrays are free of grating lobe and were supplied simply with a uniform amplitude which improves efficiency of the direct current to radio frequency conversion and system reliability in communication satellites."

"Sistem telemetri yang digunakan pada Roket Sonda RX-450 milik BRIN-ORPA (Badan Riset dan Inovasi Nasional-Organisasi Riset Penerbangan dan Antariksa) Pustekroket Indonesia telah memanfaatkan antena blade sebagai pemancar untuk mengirimkan data lokasi dan kondisi roket kepada sistem penerima stasiun bumi. Karena merupakan antena directional, maka dibutuhkan dua buah antena blade yang dihubungkan dengan perangkat splitter untuk memenuhi area jangkauan 360°. Dengan adanya penambahan perangkat, maka dibutuhkan daya tambahan pada muatan roket. Untuk mengatasi hal ini maka diperlukan antena pengganti sehingga dengan satu buah antena dapat melingkupi semua area jangkauan dan memiliki gain yang tinggi. Pada penelitian ini, dilakukan rancang bangun antena conformal 2.4 GHz untuk menghindari gangguan aerodinamis akibat bentuk antena sekaligus memiliki polarisasi melingkar untuk menghindari data transmisi hilang akibat loss polarisasi terhadap ground station. Dalam proses perancangan antena, untuk mendapatkan parameter yang sesuai dilakukan simulasi menggunakan perangkat lunak CST Studio Suite. Bahan yang digunakan untuk membuat antena ini adalah Roger 6010LM yang mempunyai ketahanan terhadap suhu hingga 500°C sehingga sesuai untuk diaplikasikan pada badan roket. Dari hasil pengukuran menggunakan substrat Roger 6010LM (εr = 10.2 dan δ = 0.0023) diperoleh bandwidth antena sebesar 71 MHz dengan rentang frekuensi 2412 – 2483 MHz. Gain antena maksimum diperoleh pada frekuensi 2.43 GHz sebesar 7.8 dB dan gain minimum pada frekuensi 2.47 GHz sebesar 4.5 dB. Dengan bentuk conformal pada struktur badan roket, didapatkan pola radiasi menyerupai isotropis yang berlekuk. Di samping itu, dengan metode Hilbert curve dengan slot-U pada ground plane diperoleh polarisasi melingkar dengan nilai axial ratio (AR) ≤ 2 dB.

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The telemetry system used in the sounding rocket RX-450 belong to National Research and Innovation Agency (BRIN) Indonesia has utilized the blade antenna as a transmitter to send data consist of rocket’s location and condition to the receiving system of ground station. Since it is a directional antenna, it takes two blade antennas connected with a splitter device to cover 360° coverage area. With the addition of the device, additional power is needed on the rocket payload. To overcome this problem, a replacement of antenna is needed so that one antenna can cover all coverage areas and has high gain. In this study, a conformal 2.4 GHz was designed to avoid aerodynamic disturbances due to the shape of the antenna as well as having circular polarization to avoid data transmission loss due to polarization loss with ground station. Antenna was simulated using CST Studio Suite software to obtain good antenna’s parameters. The material used to make this antenna is Roger 6010LM which has resistance to high temperatures up to 500°C so it is suitable for application in rocket bodies. From the measurement results using the Roger 6010LM substrate (εr = 10.2 and δ = 0.0023) the antenna bandwidth is 71 MHz with a frequency range of 2412-2483 MHz. The maximum gain of the antenna is obtained at a frequency of 2.43 GHz by 7.8 dB and the minimum gain at a frequency of 2.47 GHz is 4.5 dB. With conformal shape on the structure of the rocket body, we get an almost isotropic radiation pattern. In addition, using the Hilbert curve method with a U-slot on the ground plane, a circular polarization with axial ratio (AR) ≤ 2 dB is obtained."

"Dunia industri merupakan bagian yang tidak dapat dipisahkan dari penggunaan logam dan paduannya. Salah satu tantangan terbesar dan terumit bagi industri adalah bagaimana melindungi logam tersebut dari korosi. Baja karbon dan baja tahan karat merupakan material yang umum digunakan dalam industri. Kedua material tersebut memiliki karakteristik yang berbeda. Penelitian ini dilakukan untuk mengetahui mekanisme pembentukan lapisan pasif pada baja AISI 1018 dan baja 316 L dan juga efisiensi dari penggunaan inhibitor Na2S2O3 pada baja AISI 1018 dalam larutan NaCl 3,5%. Adapun pengujian yang dilakukan terdiri dari pengamatan mikroskopik, pengujian kehilangan berat, pengujian polarisasi, pengujian EIS, dan pengujian SEM-EDS. Hasil dari penelitian menunjukkan bahwa fenomena pasivasi pada baja AISI 1018 terlihat pada penambahan inhibitor Na2S2O3 2000 ppm dimana terbentuknya dua daerah terjadinya pasivasi, yaitu daerah aktif dan daerah pseudo-pasif pada potensial -0,7 V. Sedangkan pada baja tahan karat 316 L fenomena pasivasi ditunjukkan oleh tiga daerah, yaitu daerah aktif, daerah pasif, dan daerah transpasif. Fenomena pasivasi ini dimulai pada potensial -0,3 V dengan rapat arus 2,51 x 10-4 A/cm2 dan kemudian akan memasuki daerah transpasif pada 0,5 V. Nilai efisiensi inhibitor Na2S2O3 pada konsentrasi 1000 ppm sebesar 23,25%, 1500 ppm sebesar 47,45%, 2000 ppm sebesar 59,78%, dan 2500 ppm sebesar 47,43%.

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The industrial world is an inseparable part of the use of metals and their alloys. One of the biggest challenges for the industry is how to protect the metal from corrosion. Carbon steel and stainless steel are materials commonly used in industry. The two types of materials have different characteristics. This research was conducted to determine the mechanism of the formation of a passive layer on AISI 1018 steel and 316 L steel and also the efficiency of the use Na2S2O3 inhibitor on AISI 1018 steel in a 3,5% NaCl solution. The research conducted consisted of optical microscopy observation, weight loss testing, polarization testing, EIS testing, and SEM-EDS testing. The results of the study indicate that the phenomenon of passivation in AISI 1018 steel was seen in the addition of 2000 ppm Na2S2O3 inhibitor where the formation of two regions of passivation, namely the active region and the pseudo-passive region at a potential of -0,7 V. Meanwhile, in SS 316 L steel, the passivation phenomenon is indicated by three regions, namely the active region, passive region, and transpassive region. This passivation phenomenon starts at a potential of -0,3 V with a current density of 2,51 x 10-4 A/cm2 and will enter the transpassive region at 0,5 V. The efficiency values of Na2S2O3 inhibitor at concentrations of 1000 ppm is 23,25%, 1500 ppm is 47,45%, 2000 ppm is 59,78%, and 2500 ppm is 47,43%."