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"Optical differentiation is one of many methods in the optical data processing that is useful for, e.g. image contouring. In this thesis, the differentiation filter is caried out based on the spatial filtering techniques. The ob ject is transformed with a Fourier lens to obtain the spatial frequency spectrum of the object at the Fourier plane. A spatial differentiation filter is placed at the Fourier plane. And finally, with another lens the filtered spectrum is transformed back to obtain the output image. The critical step of the experiment is the design and the fabrication of the filter. In this thesis, two kinds of models have been used to approximate the differentiation filters: (1) multi-step function and (2) Gaussian spot. The multi-step function is intended to approximate the first order differentiation filter. However, due to the photographic limitations, the multi-step function has become a single step function or simply a high-pass filter. Nevertheless, the result may be useful as the approximation of the second (not the first) order differentiation. A filter with a diameter of 0.4 mm appears to give a good result for an object consisting of letters of 4 mm high. To obtain the Gaussian spot, a He-Ne laser beam spot with 6328 nm has been used. with several attenuations, the laser beam spot has been recorded with various shutter speeds in an open camera. It appear that the Gaussian filter is a very good approximation of the second order differentiation filter. Compared to the high-pass filter, it gives higher S/N ratio. The Gaussian spot obtained with a shutter speed of 1/4000 and minimum attenuation gives the best image output. However, none of the filters gives the first order differentiation output."

"Pada makalah ini dilaporkan hasil rancang bangun penyempurnaan probe optik untuk mengukur konsentrasi suspensi phytoplankton. Dari hasil pengujian skala laboratorium dengan menggunakan kultur Scenedesmus sp. ditunjukkan bahwa untuk rentang konsentrasi dari 10 pangkat 4 hingga di sekitar 1 x 10 pangkat 6 sel/mL intensitas fluoresensi pada λ = 685 nm memiliki hubungan yang linier terhadap konsentrasi sel dengan konstantaproporsianlγ = 4×10-5mL/sel. sementara itu untuk rentang konsentrasi yang sama, logaritma intensitas pada λ= 405 nm berbanding lurus dengan konsentrasi sel dengan konstatnta proporsional β= ?2×10-7mL/sel.

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This paper discusses the results of improved optical probe that works according to optical fluorescence and absorption phenomena for measuring the phytoplankton suspension concentrations. Measurements are made on the Scenedesmus sp. culture. The laboratory test has shown that range of concentration from 10 up to around 1 x 10 cells/mL; fluorescence intensity at λ= 685 nm; and logarithmic of transmission intensity at λ = 405 nm are proportional to the cell concentration linear with proportional constant γ=4×10-5 and β= ?2×10-7mL/cell respectively."

"Termotivasi untuk memperluas studi teoritis yang pernah dilakukan sebelumnya, kami melakukan perhitungan konduktivitas optik tergantung temperatur pada La0:7Ca0:3MnO3 dalam rentang energi foton yang luas hingga 22 eV, untuk menangkap transisi logam ke insulator, dengan tetap mempertahankan profil ketergantungan terhadap temperatur yang sesuai dengan data eksperimen pada energi foton yang lebih tinggi. Sistem dimodelkan dengan koordinasi Mn-O sederhana melalui metode tight binding dengan beberapa integral hopping dianggap sebagai fungsi magnetisasi. Menggabungkan efek Jahn-Teller statis, Coulomb-Hubbard dan interaksi pertukaran magnetik, kami dapat mereproduksi tren kualitatif dari konduktivitas optik yang tergantung pada suhu, terutama untuk rezim energi rendah dan tinggi, seperti yang diamati dalam data eksperimen. Hasil kami menggarisbawahi pentingnya efek korelasi yang saling mempengaruhi pada derajat kebebasan kisi, muatan dan magnet dalam menentukan profil keseluruhan respon optik terhadap temperatur dari manganite, hubungannya dengan respon fisika optik energi tinggi dan sifat transpor listrik DC.

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Motivated to extend our previous theoretical study, we perform temperaturedependent optical conductivity calculation on La0:7Ca0:3MnO3 in a wide photon energy range up to 22 eV, to capture the metal to insulator transition, while still preserving in most way the correct temperature-dependent profile at higher photon energies. The system is modeled with a simple Mn-O coordination via the tight binding method with some hopping integrals being considered as functions of magnetization. Incorporating static Jahn-Teller effect, Coulomb-Hubbard and magnetic exchange interactions, we are able to reproduce the qualitative trend of the temperature-dependent optical conductivity, especially for the low-and high-energy regimes, as observed in the experimental data. Our results underline the importance of correlation effects due to interplay of lattice, charge, and magnetic degrees of freedom in determining the overall profile of temperature-dependent optical response of manganites, connecting the physics of high-energy optical response and the transport properties at the dc limit."

"The most comprehensive treatment of FFTs to date. Van Loan captures the interplay between mathematics and the design of effective numerical algorithms--a critical connection as more advanced machines become available. A stylized Matlab notation, which is familiar to those engaged in high-performance computing, is used. The Fast Fourier Transform (FFT) family of algorithms has revolutionized many areas of scientific computation. The FFT is one of the most widely used algorithms in science and engineering, with applications in almost every discipline. This volume is essential for professionals interested in linear algebra as well as those working with numerical methods. The FFT is also a great vehicle for teaching key aspects of scientific computing."