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"This volume sharpens our picture of the applications of conformal invariance, introducing non-local observables such as loops and interfaces before explaining how they arise in specific physical contexts. It then shows how to use conformal invariance to determine their properties. Moving on to cover key conceptual developments in conformal invariance, the book devotes much of its space to stochastic Loewner evolution (SLE), detailing SLE’s conceptual foundations as well as extensive numerical tests. The chapters then elucidate SLE’s use in geometric phase transitions such as percolation or polymer systems, paying particular attention to surface effects. "

"Berdasarkan data World Health Organization (WHO) hingga 6 Januari 2022, terdapat 4.264.669 kasus terkonfirmasi COVID-19 dengan jumlah kematian sebanyak 144.116 pasien di Indonesia. Figur ini meningkat drastis saat dibandingkan data WHO hingga 25 April 2021 sebesar 1.636.792 kasus terkonfirmasi dengan jumlah kematian sebanyak 44.500 pasien. Varian B.1.617.2 atau lebih umum dikenal sebagai Delta dinyatakan hadir di Indonesia pada 3 Mei 2021 dengan dua kasus positif terdeteksi di Jakarta. Varian ini memiliki daya tular yang lebih tinggi dan mengakibatkan gejala COVID-19 lebih parah sehingga menjadi varian yang mendominasi persebaran COVID-19 di Indonesia. Menurut revisi protokol tatalaksana COVID-19 edisi ketiga, seorang pasien COVID-19 dapat dibedakan menjadi lima kategori berdasarkan severitas kasus yang diderita dengan tingkat risiko tertinggi yaitu kritis. Pasien COVID-19 yang digolongkan kategori kritis menunjukkan gejala Acute Respiratory Distress Syndrome (ARDS), sepsis, dan syok sepsis. Dengan menganalisisis berbagai faktor yang terkait dengan gejala-gejala tersebut, dapat dibangun sebuah pemahaman berbentuk model Machine Learning untuk mengestimasi tingkat risiko kasus seorang pasien COVID-19. Model Machine Learning yang dibangun mencakup berbagai model, seperti model berbasis tree maupun berbasis ensemble. Dalam penelitian ini, tingkat risiko disimplikasi menjadi dua, yaitu severe dan non-severe berdasarkan urgensi perawatan khusus di rumah sakit. Untuk menentukan model optimal, digunakan metrik evaluasi Recall guna memberi perhatian kepentingan pasien tergolong kasus severe berhasil dideteksi severe dengan benar. Digunakan data pasien positif COVID-19 pada salah satu rumah sakit di Jakarta dari Januari 2020 hingga Agustus 2021 yang dibagi menjadi dua periode, sebelum dan sesudah adanya varian Delta. Dengan pembagian data ini, dapat dibangun tiga model Machine Learning yaitu model sebelum Delta, model setelah Delta, dan model keseluruhan. Dari ketiga model yang terbangun, akan diperiksa apakah ada perbedaan yang signifikan. Lebih lanjut, model-model Machine Learning yang terbentuk akan diuji tingkat kepercayaan terhadap prediksinya menggunakan metode Conformal. Diperoleh model Random Forest berhasil mengklasifikasikan data COVID-19 dengan lebih baik dibanding model-model lainnya. Model Random Forest pada seluruh variabel respon mencapai Recall 86,49%. Dengan identifikasi 4 variabel terpenting, model mencapai Recall 80,18%. Mendukung hasil ini, model percaya 90% dengan prediksi yang dihasilkan.

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According to World Health Organization (WHO) data to 6 January 2022, there have been 4.264.669 confirmed cases of COVID-19 with 144.116 patient deaths in Indonesia. This figure has significantly increased when compared with WHO data to 25 April 2021, where there were 1.636.792 confirmed cases with 44.500 patient deaths. The B.1.617.2 variant or more commonly known as Delta was announced to be present in Indonesia on 3 May 2021 with two positive cases detected in Jakarta. This variant is more contagious and causes worse COVID-19 symptoms which made it the dominating variant of COVID-19 distribution in Indonesia. According to the revision of COVID-19 governance protocol third edition, a patient of COVID-19 can be differentiated to five categories depending on the severity of their case with the highest risk being critical. A patient of COVID-19 that is categorized as critical will show symptoms of Acute Respiratory Distress Syndrome (ARDS), sepsis, and sepsis shock. Through analyzing the factors that are related to these symptoms, we can build an understanding in the form of Machine Learning to estimate a COVID-19 patient’s degree of severity. The Machine Learning model that will built encompasses many models, such as tree-based models and ensemble-based models. In this research, this degree is simplified into two, which are severe and non-severe with accordance to the urgency of special care in hospitals. To determine optimal models, the Recall evaluation metric is used as a means to give better attention to making sure severe patient cases are properly classified as severe. The data used will be positive COVID-19 patients in a Jakarta-based hospital from January 2020 until August 2021 which is split into two periods of before and after the presence of Delta variant. With this division, we can build three Machine Learning models which has it learn before Delta, after Delta, and overall. From each of these built models, we will then determine if there exists a significant difference between them. Furthermore, the Machine Learning models that are built will be tested in its confidence on their own prediction using the Conformal method. We procure that Random Forest model classifies COVID-19 data better than all other models. Random Forest built on all response variables achieve 86,49% Recall. With the identification of 4 most important variables, the model achieves 80,18%. Supporting this result, the model has 90% faith in its prediction."

"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."

"This book is devoted to the Beltrami equations that play a significant role in geometry, analysis and physics and, in particular, in the study of quasiconformal mappings and their generalizations, Riemann surfaces, Kleinian groups, Teichmuller spaces, Clifford analysis, meromorphic functions, low dimensional topology, holomorphic motions, complex dynamics, potential theory, electrostatics, magnetostatics, hydrodynamics and magneto-hydrodynamics.The purpose of this book is to present the recent developments in the theory of Beltrami equations; especially those concerning degenerate and alternating Beltrami equations. The authors study a wide circle of problems like convergence, existence, uniqueness, representation, removal of singularities, local distortion estimates and boundary behavior of solutions to the Beltrami equations. The monograph contains a number of new types of criteria in the given problems, particularly new integral conditions for the existence of regular solutions to the Beltrami equations that turned out to be not only sufficient but also necessary.The most important feature of this book concerns the unified geometric approach based on the modulus method that is effectively applied to solving the mentioned problems. Moreover, it is characteristic for the book application of many new concepts as strong ring solutions, tangent dilatations, weakly flat and strongly accessible boundaries, functions of finite mean oscillations and new integral conditions that make possible to realize a more deep and refined analysis of problems related to the Beltrami equations"

"Numerical grid generation plays a critical role in any scientific computing problem when the geometry of the underlying region is complex or when the solution has a complex structure. The mathematical aspects of grid generation are discussed to provide a deeper understanding of the algorithms and their imitations. Variational methods are emphasized because they are more robust, but elliptic and transcendental algebraic methods are also considered."

"Latar Belakang: Radiasi kraniospinal adalah metode radiasi yang sering digunakan pada kasus keganasan sistem saraf pusat yang menyebar ke cairan cerebrospinal, sehingga area radiasinya sangat luas meliputi seluruh otak dan canalis spinalis. Akibat daerah radiasi yang luas, area radiasi harus dibagi menjadi beberapa lapangan yang menghasilkan kesulitan dalam mengatasi junction antar lapangan tersebut.Kesulitan lain adalah banyaknya organ kritis yang terlibat dan usiapasien yang mayoritas anak-anak. Saat ini belum terdapat data penelitian yang menganalisis radiasi kraniospinal dengan teknik Three Dimentional Conformal Radiotherapy 3D-CRT, Intensity Modulated Radiotherapy IMRT, dan IMRT-Helical Tomotherapy HT di Indonesia. Metode: studi eksperimental eksploratorik dengan melakukan intervensi planning terhadap 10 data CT plan pasien kraniospinal yang diradiasi di Departemen Radioterapi RSUPN Cipto Mangunkusumo. Dosis 36 Gy diberikan dalam 20 fraksi.Cakupan PTV kranial dan spinal dievaluasi menggunakan indeks konformitas CI dan indeks homogenitas HI.Dilakukan pencatatan parameter organ kritis lensa mata, mata, kelenjar parotis, kelenjar submandibula, tiroid, paru-paru, jantung, ginjal, testis dan ovarium, serta paparan radiasi pada seluruh tubuh.Selain itu juga dilakukan pencatatan jumlah MU dan durasi sinar beam on time.Hasil: Teknik HT adalah teknik terbaik dalam pencapaian angka HI dan CI serta perlindungan terhadap organ kritis, namun memiliki paparan radiasi seluruh tubuh tertinggi dibandingkan teknik 3D CRT dan IMRT selain nilai MU tertinggi dan durasi penyinaran terlama sehingga harus dipertimbangkan penggunaannya pada pasien anak-anak karena resiko secondary malignancy yang tinggi. Teknik 3D CRT dengan arah sinar opposing lateral untuk lapangan kranial dan dari posterior untuk lapangan spinal memiliki nilai HI dan CI terburuk dengan keterbatasan kemampuan melindungi organ kritis namun memiliki paparan radiasi seluruh tubuh dan MU terendah serta durasi penyinaran terpendek.

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Background: Craniospinal radiation is a method of radiation that is often used in cases of malignancy of the central nervous system that spread to cerebrospinal fluid, so that the area of ??radiation is very broad covering the entire brain and spinal canal. Due to the large area of radiation, the radiation area must be divided into several fields that produce difficulty in overcoming the inter-field junction. In addition, the number of critical organs involved and the age of patients with the majority of children result in separate considerations in the choice of craniospinal radiation techniques. Currently there is no research data that analyzes craniospinal radiation with Three Dimentional Conformal Radiotherapy 3D-CRT, Intensity Modulated Radiotherapy-Step and Shoot IMRT-SS, and IMRT-Helical Tomotherapy HT techniques in Indonesia. Method: exploratory experimental study by planning intervention on 10 CT plan data of craniospinal patients radiated in Radiotherapy Department of Cipto Mangunkusumo General Hospital. Dose 36 Gy is given in 20 fractions. Cranial and spinal PTV coverage was evaluated using the conformity index CI and homogeneity index HI. Performed recording of critical organ parameters of lens, eye, parotid gland, submandibular gland, thyroid, lung, heart, kidney, testis and ovary, and exposure to radiation throughout the body. In addition, also recorded the number of MU and the duration of the beam. Results: The HT technique is the best technique for achieving HI and CI figures and protection of critical organs, but has the highest body-wide radiation exposure compared to CRT and IMRT 3D techniques in addition to the highest MU values and longest exposure duration so should be considered in children high risk of secondary malignancy. 3D CRT technique with opposite lateral beam direction for the cranial field and from the posterior to the spinal field has the worst HI and CI values with limited ability to protect critical organs but has the lowest total body radiation and MU exposure as well as the shortest duration of irradiation. "