Judul: Pencitraan dan Identifikasi Material Dasar Perairan dan Kapal Karam di Perairan Mempawah Menggunakan Instrumen Side Scan Sonar
Abstrak: Side Scan Sonar adalah instrumen yang dapat digunakan untuk melihat kenampakan permukaan dasar laut dalam bentuk 2 dimensi serta mengetahui informasi dasar perairan. Penelitian ini bertujuan menggambarkan kenampakan dasar perairan dan mendeteksi objek serta mengetahui nilai hambur balik melalui analisa nilai amplitudo dengan metode Continuous Wavelet Transform. Data yang digunakan adalah hasil pendeteksian instrumen CM-2 C-Max Side Scan Sonar dengan frekuensi 325 kHz di Perairan Mempawah Kalimantan Barat dengan 4 jalur survei. Pengolahan data Side Scan Sonar meliputi koreksi geometrik dan radiometrik. Koreksi geometrik berfungsi untuk mengetahui dan menetapkan posisi objek sebenarnya dengan bottom tracking, slant range correction, dan layback correction. Koreksi radiometrik dilakukan untuk memperbaiki nilai piksel agar citra yang dihasilkan sesuai dengan objek sebenarnya meliputi Beam Angle Correction (BAC), Empirical Gain Normalization (EGN), Automatic Gain Control (AGC), dan Time Varying Gain (TVG). Pada riset ini ditemukan 2 objek kapal karam dengan nilai amplitudo kapal 1 sebesar 27152 - 32564 mV dan kapal 2 sebesar 24320 - 32522 mV. Rata rata nilai amplitudo dari sedimen berkisar 1408 - 14336 mV. Analisa Continuous Wavelet Transform menunjukan material dengan susunan kasar, keras, dan padat memiliki intensitas berwarna merah pada scalogram sedangkan material dengan susunan yang halus dan lunak akan menunjukan intensitas berwarna biru pada scalogram.
Keyword: Amplitudo, Continuous Wavelet Transform, Geometrik, Radiometrik, Side Scan Sonar., Geometrik, Radiometrik

Judul: Processing and Analysis of Seabed Acoustic Backscatter in Yos Sudarso Bay, Jayapura Using Side Scan Sonar Instrument
Abstrak: Side Scan Sonar merupakan instrumen yang digunakan untuk pencitraan dasar laut. Side Scan Sonar mampu membedakan permukaan dasar laut seperti batuan, lumpur, pasir, serta mendeteksi keberadaan pipa dan kabel laut. Penelitian ini bertujuan menginterpretasi dasar laut secara visual dan menganalisa nilai hamburbalik (dB) dengan metode Continuous Wavelet Transform (CWT) untuk mengetahui jenis substrat dasar laut. Data yang digunakan merupakan hasil pendeteksian instrumen Side Scan Sonar CMAX CM2 Towfish di perairan Teluk Yos Sudarso dengan 3 lintasan survei. Pengolahan data citra Side Scan Sonar meliputi koreksi geometrik dan koreksi radiometrik menggunakan perangkat lunak Sonarwiz 7. Koreksi geometrik meliputi bottom track dan slant range correction, serta koreksi radiometrik meliputi Beam Angle Correction (BAC), Automatic Gain Control (AGC), dan Time Varying Gain (TVG). Konversi data menggunakan perangkat lunak XtftoSegy, ekspor nilai amplitudo dengan Seisee, kemudian menampilkan hubungan amplitudo dan waktu, serta CWT menggunakan Matlab. Hasil penelitian ini diperoleh target berupa dua pasir dan satu karang. Hasil perhitungan nilai hamburbalik karang sebesar -5,0413 dB pada lintasan 6. Nilai hamburbalik pasir sebesar -15,4362 dB pada lintasan 7. Nilai hamburbalik pasir sebesar -14,2007 dB pada lintasan 8. Analisis Continuous Wavelet Transform menunjukkan target dengan tekstur keras dan kasar memiliki intensitas berwarna kuning pada scalogram, sedangkan target dengan tekstur lebih halus dan lunak memiliki intensitas berwarna biru pada scalogram., Side Scan Sonar is an instrument that is usually used to perform seabed imaging. Side Scan Sonar can distinguish seabed such as rocks, silt, sand, and detect the existence of marine pipes and cables. The aim of this research was to interpretate the seabed visually and analyze the backscatter (dB) with Continuous Wavelet Transform (CWT) for determine the type of seabed substrate. The data used from the detection of Side Scan Sonar C-Max CM2 Towfish instrument in Yos Sudarso Bay with 3 survey lines. Processing data Side Scan Sonar Image consisting of geometric corrections and radiometric corrections using Sonarwiz 7 software. Geometric corrections consist of bottom track and slant range, and radiometric corrections consist of Beam Angle Correction (BAC), Automatic Gain Control (AGC), and Time Varying Gain (TVG). Data was converted by XtftoSegy, amplitudo values were exported by Seisee, and displaying relation of amplitude and time, and CWT using Matlab. The results of this research were two sands and one coral target. The backscatter value of coral was -5,0413 dB on line 6. The backscatter value of sand was -15,4362 dB on line 7. The backscatter value of sand was -14,2007 dB on line 8. Continuous Wavelet Transform analysis shows that targets with hard and coarse textures have a yellow intensity on the scalogram, while targets with smooth and soft textures have a blue intensity on the scalogram.
Keyword: backscatter, continuous wavelet transform, side scan sonar, yos sudarso bay

Judul: Model’s Dynamics for Lymphocytes Recovery on the HIV presence with Protease Inhibitor Therapy.
Abstrak: HIV is a member of retrovirus that especially attacks lymphocytes or white blood cells, known as CD4+ T cells. New T cells created from sources within the body such as the thymus and by proliferation of existing T cells. In this paper, influence of protease inhibitor therapy in HIV dynamics will be analyzed. The influence can be categoried in three models, which are model HIV without drug therapy, model HIV with protease inhibitor and model T cell recovery. In the models, three parameters which are uninfected cells population, infected cells population and virus population are studied. From HIV without drug therapy model it is obtained two types fixed point which are uninfected fixed point and infected fixed point. The stability of fixed point depends on basic reproduction number which is influenceed by the total number of virus produced by a cell during its lifetime. From HIV with protease inhibitor therapy model it is obtained two type fixed points. The stability of fixed point depends on basic reproduction number. Other than influenceed by the total number of virus produced by a cell during its lifetime, basic reproduction number of this model also affected by the effectiveness of a protease inhibitor. Basic reproduction number of this model is smaller than that of model HIV without drug therapy. In the model T cell recovery, new T cells created only from sources within the body, and T cells can be invulnerable to HIV infection after the therapy. From the model it is obtained only one fixed point that is uninfected fixed point. The stability of fixed point depends on basic reproduction number. The total number of virus produced by a cell during its lifetime and the effectiveness of a protease inhibitor determine the basic reproduction number. Basic reproduction number of this model is smallest than that of other models.
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