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Ditemukan 5 dokumen yang sesuai dengan query
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Szekelyhidi, Laszlo
Abstrak :
This book provides a modern introduction to harmonic analysis and synthesis on topological groups. It serves as a guide to the abstract theory of Fourier transformation. For the first time, it presents a detailed account of the theory of classical harmonic analysis together with the recent developments in spectral analysis and synthesis.
New Jersey: World Scientific, 2014
515.243 3 SZE h
Buku Teks  Universitas Indonesia Library
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Maulana Kholis Fadhlillah
Abstrak :
Peningkatan resolusi vertikal dari data seismik selalu dilakukan oleh para Geosaintis, terutama pada petroleum system. Data seismik beresolusi tinggi dapat membuat pembacaan stratigrafi bawah permukaan lebih akurat. Data seismik beresolusi tinggi dilakukan peningkatan pada bandwidth frekuensi data seismik terutama pada frekuensi rendah dan tinggi. Terdapat banyak pendekatan untuk meningkatkan frekuensi pada data seismik contohnya multiscale inversion, namun metode ini susah untuk dilakukan. Penelitian ini menggunakan pendekatan baru untuk meningkatkan frekuensi pada data seismik terutama pada frekuensi rendah dengan menggunakan Convolutional Neural Network. Penelitian ini, membahas mengenai penggunaaan Convolutional Neural Network yang dilakukan pada data seismik dikalibrasi dengan data sumur. Hasil estimasi dari metode ini dilanjutkan dengan mengestimasi reservoir tipis pada daerah penelitian. Atribut seismik khususnya Root Mean Square, digunakan untuk mengestimasi daerah reservoir dan spectral Analysis digunakan untuk melihat lebih banyak frekuensi rendah dan tinggi. Hasil yang diperoleh menunjukkan bahwa penggunaan metode Convolutional Neural Network dapat meningkatkan resolusi vertikal. Metode tersebut menghasilkan gambar yang akurat dan tegas dalam melihat lapisan-lapisan tipis. Spetral analysis menunjukkan terdapat lebih banyak frekuensi rendah dan tinggi. Hasil dari Atribut Seismik medapatkan nilai tinggi di pada inline 424, crossline 1007 dan time slice -1200 hingga -1600 ms. ......Enhancing the vertical resolution of seismic data is always carried out by geoscientists, especially in the petroleum system. High-resolution seismic data can make subsurface stratigraphic readings more accurate. an increase in the frequency bandwidth of seismic data is carried out on high resolution seismic data, especially at low and high frequencies. There are many approaches to increase the frequency of seismic data. One of the methods is multiscale inversion. the downside of this method is its level of difficulty that really high. This study uses a new approach to increase the frequency of seismic data, especially at low frequencies by using the Convolutional Neural Network. The estimation results from this method are continued by estimating the thin reservoir in the study area. Seismic attributes, especially Root Mean Square, are used to estimate the reservoir area and spectral analysis is used to see more of low and high frequencies. The results indicate that the use of the Convolutional Neural Network method can increase the vertical resolution. This method produces images that are accurate and firm in viewing thin layers. Spectral analysis also shows that there are more low and high frequencies. The result of the seismic attribute got high values at inline 424, crossline 1007 and time slice -1200 to -1600 ms.
Depok: Fakultas Matematika dan Ilmu Pengetahuan Alam Universitas Indonesia, 2022
S-pdf
UI - Skripsi Membership  Universitas Indonesia Library
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Syamil Fakhruddin Hibatulloh Arildan
Abstrak :
ABSTRAK Data gravitasi yang diperoleh pada bagian selatan Yogyakarta, tepatnya daerah bantul kearah utara, telah digunakan untuk mengidentifikasi keberadaan serta kedalaman Sesar Kali Opak. Dengan mengaplikasikan metode Multi Scale Second Vertical Derivative(MS-SVD), lokasi patahan dan kemiringan (dip) dapat diidentifikasi. Data anomali gravitasi dalam bentuk Complete Bouguer Anomaly (CBA) dilakukan kontinuasi ke atas (upward continuation) beberapa kali, sehingga didapatkan bidang anomali gravitasi pada beberapa level kontinuasi. SVD dilakukan pada setiap bidang hasil kontinuasi sehingga didapatkan lokasi yang teridentifikasi sebagai patahan, yaitu saat nilai SVD nol. UC yang berkorelasi dengan kedalaman diplot dengan lokasi SVD nol, sehingga didapatkan bentuk, besar kemiringan, lokasi dan kedalaman dari setiap patahan. Sesar Kali Opak pada bagian Utara bergeser ke arah Timur dari peta geologi, dan berkorelasi dengan nilai peta anomali CBA data gravitasi. Sesar Kali Opak sebelah Utara memiliki arah strike N600E dan besar dip 74.50 arah Barat Laut, sedangkan sebelah Selatan memiliki arah strike N670E dan besar dip 650 arah Barat Laut dengan jenis patahan normal. Estimasi bentuk dan kedalaman horizon lokasi penelitian telah diidentifikasi dengan mengaplikasikan metode Energy Spectral Analysis-Multi Window Test (ESA-MWT). Bentuk dan lokasi horizon digunakan untuk mengonfirmasi keberadaan struktur patahan di bawah permukaan daerah penelitian. Dengan mengaplikasikan analisa energi spektrum yang telah di-grid menjadi transformasi Fourier 2D (Fast Fourier Transform) dari data gravitasi. Analisa energi spektrum dilakukan pada suatu titik uji, dengan melakukan per-window-an pada peta CBA secara konstan dengan ukuran window persegi yang bertambah lebar 2 km dari window sebelumnya. Jarak antara titik uji berkisar sekitar 3-5 km pada masing-masing lintasan yang memiliki zona interest. Hasil plot masing-masing window terhadap kedalaman memperlihatkan kedalaman masing-masing horizon. Dengan menggabungkan setiap titik uji, dan melakukan plot terhadap kedalaman, maka didapatkan bentuk dan kedalaman masing-masing horizon. Terdapat dua horizon pada daerah penelitian. Horizon pertama berada pada kedalaman berkisar 2-4 km, dan horizon kedua berada pada kedalaman berkisar 6-8 km. Bentuk dari horizon pertama di sekitar Sesar Kali Opak memberikan bentuk yang sesuai dengan hasil MS-SVD , sehingga mengonfirmasi adanya patahan di lokasi tersebut
ABSTRACT
Gravitation data which obtained from southern part of Yogyakarta, precisely in Bantul towards the northern, are already used to identify the existence and the depth of Kali Opak Fault or Opak River Fault. By applying Multi Scale Second Vertical Derivative (MS-SVD) method, the location fault and dip can be identified. The gravity anomaly data in the form of Complete Bouguer Anomaly (CBA) is carried out upward continuation several times, so that the gravity anomaly data is obtained at several levels of continuation. SVD is performed on each field resulting from the continuation so that the location identified as a fault is obtained, i.e. when the SVD value is zero. UC which correlates with depth is plotted with a zero SVD location, so that the shape, the dip size, location, and depth of each fault are obtained. The northern part of Opak River Fault shifts eastward from geological map, and correlates with the CBA anomaly map of gravity data. The northern part of Opak River Fault has a N600E strike direction and a large 74.50 dip in the northwest direction meanwhile, the southern part has a N670E strike direction and a large 650 northwest dip with normal fault type. The estimation of shape and depth of the research location horizon has been identified by applying Energy Spectral Analysis-Multi Window Test (ESA-MWT) method. The shape and horizon location is used to confirm the existence of a fault structure beneath the surface of the study area. By applying grid-spectrum energy analysis to transform into Fourier 2D from gravity data. Energy spectrum analysis is carried out at a test point, by constantly windowing the CBA map with a square window size that increases in width 2 km from the previous window. The distance between the test points ranges from 3-5 km to each track that has an interest zone. The results of the plots of each window towards the depth show the depth of each horizon. By combining each test point, and plotting the depth, the shape and depth of each horizon are obtained. There are two horizons in the study area. The first horizon is at depths ranging from 2-4 km, and the second horizon is at depths ranging from 6-8 km. The shape of the first horizon around the Opak River Fault gives a shape that matches the MS-SVD results, thus confirming the appearance of fault at that location.
2019
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UI - Skripsi Membership  Universitas Indonesia Library
cover
Abstrak :
This book offers a comprehensive introduction to the theory of structural dynamics, highlighting practical issues and illustrating applications with a large number of worked out examples. In the spirit of learning by doing it encourages readers to apply immediately these methods by means of the software provided, allowing them to become familiar with the broad field of structural dynamics in the process. The book is primarily focused on practical applications. Earthquake resistant design is presented in a holistic manner, discussing both the underlying geophysical concepts and the latest engineering design methods and illustrated by fully worked out examples based on the newest structural codes. The spectral characteristics of turbulent wind processes and the main analysis methods in the field of structural oscillations due to wind gusts and vortex shedding are also discussed and applications illustrated by realistic examples of slender chimney structures. The user‐friendly software employed is downloadable and can be readily used by readers to tackle their own problems.
Berlin: Springer Nature, 2019
e20509734
eBooks  Universitas Indonesia Library
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Abstrak :
The multiple signal demixing and parameter estimation problems that result from the impacts of background noise and interference are issues that are frequently encountered in the fields of radar, sonar, communications, and navigation. Research in the signal processing and control fields has always focused on improving the estimation performance of parameter estimation methods at low SNR and maintaining the robustness of estimations in the presence of model errors. This book presents a universal and robust relaxation estimation method (RELAX), and introduces its basic principles and applications in the fields of classical line spectrum estimation, time of delay estimation, DOA estimation, and radar target imaging. This information is explained comprehensively and in great detail, and uses metaphors pertaining to romantic relationships to visualize the basic problems of parameter estimation, the basic principles of the five types of classical parameter estimation methods, and the relationships between these principles. The book serves as a reference for scientists and technologists in the fields of signal processing and control, while also providing relevant information for graduate students in the related fields.
Singapore: Springer Nature, 2019
e20509412
eBooks  Universitas Indonesia Library