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"ABSTRACT As transmission medium in optical communication system, optical fiber is also characterized by elastic properties beside of transmission properties of optical fiber. The Young Modulus of Elasticity of optical fiber could be measured by considering a bare optical fiber as cantilever which resonant with an acoustical vibration. To detect the cantilever vibration, a HeNe laser light is launched into the cantilever of optical fiber through its free end and the output laser light is detected by a PMT and observed by the channel 2 of an oscilloscope. Channel 1 of the oscilloscope observes the signal of the acoustical vibration. Regulating both the frequency and amplitude of the vibration or the position of the pinhole of the PMT, the resonance frequency of the cantilever could be detected accurately. Using the data of the resonance frequencies of various length of the cantilever has been calculated. "

"Pada penelitian ini dilakukan perancangan konfigurasi perangkat optik untuk mengukur konsentrasi fitoplankton dalam medium cair Konfigurasi perangkat tersebut bekerja dengan memanfaatkan fenomena fluoresensi, yang terdiri dari laser dioda ungu (A = 405nm, P = 4mW, repetisi pulsa = l ms), curette, filter optik, dan fotodioda. Dari pengujian terhadap kultur ('hlurellu sp. didapatkan bahwa untuk rentang konsentrasi 0 - 15. 106 semi diperoleh hubungan yang konsisten antara intensitas fluoresensi dengan kenaikan konsentrasi sel, yaitu meningkat secara tinier seiring dengan peningkatan konsentrasi sel. Gradien untuk rentang konsentrasi yang tinggi (1106 - 15 . 10'' sel/ml) adalah < 5. 10 9nillsel, sedangkan untuk rentang konsentrasi rendah (2'10- 1 .10'sel/ml) 610-9ml/sel. Ambang pengukuran konsentrasi ('lifore la sp. di sekitar 2. 102 sel/ml.

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In this research, has been designed the optical device configuration aim for measuring the concentration of phytoplankton suspension. The device works according to fluorescence phenomenon, composed of violet diode laser (, = 405nm, P = 4mW, pulse repetition = l ms), cuvette, optical filter, and photodiode. From the measurement results, it is shown that the fluorescence intensity has a consistent relationship with the ('h/orellu sp, concentration in the range of 0 - 15'106 cell/nil, increase linearly to the cell concentration. The gradient for high concentration (1 10" -15. 10` cell/ml) is < 5 ' 10'9ml/cell, while for low concentration (2-102 - 1I0" cell/ml) is = 6.10 `'nil/cell. The threshold (Wore/la sp. concentration of measurement is about 2.102 cell/ml."

"One of the critical issues in semiconductor technology is the precise electrical characterization of ultra-shallow junctions. Among the plethora of measurement techniques, the optical reflectance approach developed in this work is the sole concept that does not require physical contact, making it suitable for non-invasive in-line metrology. This work develops extensively all the fundamental physical models of the photomodulated optical reflectance technique and introduces novel approaches that extend its applicability from dose monitoring towards detailed carrier profile reconstruction. It represents a significant breakthrough in junction metrology with potential for industrial implementation."

"Latar belakang: Uveitis merupakan sekelompok penyakit yang ditandai dengan adanya inflamasi intraokular. Derajat inflamasi bilik mata depan yang dinilai secara semi-kuantitatif berdasarkan penghitungan sel dan flare, digunakan untuk menentukan keparahan penyakit, efektivitas terapi serta pemantauan jangka panjang pada uveitis anterior dan panuveitis.Tujuan: Menilai validitas dan reliabilitas optical coherence tomography (OCT) segmen anterior dalam mengukur inflamasi bilik mata depan secara kuantitatif sebagai metode alternatif dari standar baku pengukuran semi-kuantitatif, Kriteria SUN.Metode: Studi ini adalah studi potong lintang, prospektif. Penghitungan jumlah sel menggunakan optical coherence tomography dengan bantuan ImageJ dilakukan oleh dua penilai yang berbeda. Hasil: Sebanyak 30 mata yang berasal dari 24 pasien diikutkan dalam penelitian. Sebanyak 80% pasien menderita panuveitis dengan tuberkulosis sebagai etiologi tersering (50%). Uji kesesuaian Cohen’s kappa pada protokol multiple line scans didapatkan nilai 0,352 (p=0,000) sedangkan protokol single line scan didapatkan nilai -0,218 (p=0,032). Uji korelasi Gamma protokol multiple line scans didapatkan nilai rho=0,595 (p=0,002) sedangkan protokol single line scan didapatkan nilai rho=-0,210 (p=0,313). Nilai inter-rater protokol multiple line scans menunjukkan hasil sangat baik sedangkan protokol single line scan baik (0,986 dan 0,892, p<0,001).Kesimpulan: OCT segmen anterior menghasilkan data kuantitatif sel inflamasi pada bilik mata depan. Jumlah sel bilik mata depan yang dihitung menggunakan OCT segmen anterior protokol multiple line scans menunjukkan korelasi sedang dan kesesuaian minimal dengan Kriteria SUN.

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Background: Uveitis is a group of diseases characterised by intraocular inflammation. The evaluation of anterior chamber inflammation, conducted through a semi-quantitative assessment involving cell counts and flares, plays a pivotal role in determining disease severity, assessing therapeutic effectiveness, and facilitating long-term monitoring in anterior uveitis and panuveitis cases.

Purpose: To evaluate the validity and reliability of anterior segment optical coherence tomography (AS-OCT) as a quantitative measurement tool for assessing anterior chamber inflammation. The objective is to explore its potential as an alternative method to the standard semi-quantitative measurement defined by the SUN Criteria.

Methods: A prospective, cross-sectional study was conducted for this purpose. The anterior chamber cell numbers were quantified using anterior segment optical coherence tomography, assisted by ImageJ, and assessed independently by two raters.

Result: The study included a total of 30 eyes from 24 patients. Panuveitis was observed in 80% of the patients, with tuberculosis identified as the predominant etiology (50%). The Cohen’s kappa test, conducted on the multiple-line scan protocol, yielded a value of 0.352 (p=0.000), while the single-line scan protocol showed a value of -0.218 (p=0.032). The Gamma correlation test for the multiple-line scan protocol demonstrated a value of rho=0.595 (p=0.002), whereas the single-line scan protocol had a value of rho=-0.210 (p=0.313). Inter-rater values for the multiple-line scan protocol indicated excellent agreement (0,986, p<0.001), while the single-line scan protocol showed good agreement (0.892, p<0.001).

Conclusion: OCT yielded quantitative data on anterior chamber inflammatory cells. Quantifying anterior chamber cells through the multiple line scan protocols of anterior segment OCT showed a moderate correlation and minimal agreement with the SUN Criteria."

"This book presents novel research ideas and offers insights into radar system design, artificial intelligence and signal processing applications. Further, it proposes a new concept of antenna spatial polarization characteristics (SPC), suggesting that the antenna polarization is a function of the spatial direction and providing new ideas for radar signal processing (RSP) and anti-jamming. It also discusses the design of an advanced signal-processing algorithm, and proposes new polarimetric and anti-jamming methods using antenna inherent properties. The book helps readers discover the potential of radar information processing and improve its anti-interference and target identification ability. It is of interest to university researchers, radar engineers and graduate students in computer science and electronics who wish to learn the core principles, methods, algorithms, and applications of RSP."

"Optical coherence tomography represents the ultimate noninvasive ocular imaging technique although being in the field for over two-decades. This book encompasses both medical and technical developments and recent achievements. Here, the authors cover the field of application from the anterior to the posterior ocular segments (Part I) and present a comprehensive review on the development of OCT. Important developments towards clinical applications are covered in Part II, ranging from the adaptive optics to the integration on a slit-lamp, and passing through new structural and functional information extraction from OCT data. "

"Padi mempunyai peran penting dalam menjamin ketahanan pangan di Indonesia, sehingga penelitian terkait lahan sawah sangat penting. Identifikasi lahan sawah dari data penginderaan jauh dengan akurasi yang tinggi di wilayah tropik Indonesia merupakan tantangan penelitian. Metode yang paling akurat untuk identifikasi lahan sawah adalah dengan menggunakan pendekatan fenologi dan integrasi data multi-sumber. Namun, pendekatan ini tidak mempertimbangkan karakteristik spektral dan temporal yang rinci. Penelitian ini mengusulkan penggabungan semua fitur spektral dan fitur temporal yang rinci dengan mempertimbangkan periode musim tanam padi dari data sensor optik Sentinel-2 dan sensor SAR Sentinel-1 dengan tujuan mendapatkan klasifikasi lahan sawah dengan akurasi tinggi. Metode identifikasi lahan sawah dalam penelitian ini meliputi pengolahan awal, ekstraksi fitur temporal dengan kuantil rinci, seleksi fitur spektro-temporal dengan menggunakan Leave-One-Out (LOO), fusi fitur dan klasifikasi dengan algoritma machine learning. Hasil penelitian menunjukkan bahwa klasifikasi lahan sawah terbaik adalah dengan menggunakan periode tanam pada musim hujan. Fitur spektral dan temporal (spektro-temporal) terbaik untuk data optik adalah kuantil 30% dan 90% dari Short Wave Infra-Red-1 (SWIR1), RedEdge-4 (RE4), RedEdge-1 (RE1), dan RedEdge-2 (RE2). Fitur spektro-temporal terbaik untuk data SAR adalah kuantil 10% dan 90% dari hamburan balik polarisasi vertical transmit - horizontal receive (VH). Hasil fitur yang dipilih menggambarkan fenologi pertumbuhan padi selama penggenangan, maksimum vegetatif dan bera (pasca panen). Penggabungan fitur spektro-temporal dari data optik dan SAR meningkatkan akurasi klasifikasi menjadi 95,06±0,50%.

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Rice plays an important role in ensuring food security in Indonesia. Therefore, paddy fields related research is important. Identifying paddy fields with high accuracy using remote sensing is a challenging in Indonesia. The most accurate method for paddy fields identification is using phenological approach and multi-source data integration. However, these approaches do not consider the comprehensive spectral and temporal characteristic data in tropical regions. This research proposed the fusion of all spectral and detailed statistical temporal features considering the period of the paddy growing season from Sentinel-2 optical and Sentinel-1 SAR data to achieve a high accuracy paddy fields classification. The paddy fields identification method in this research starts with preprocessing, temporal feature extraction using detail quantile, spektro-temporal fetaure selection using Leave-One-Out (LOO), feature fusion, and then applied machine learning classification algorithm. The results show that the best paddy fields classification is using the planting period during the rainy season. The best spectral and temporal (spectro-temporal) features for optical data are the 30% and 90% quantiles of Short Wave Infra-Red 1 (SWIR1), RedEdge-4 (RE4), RedEdge-1 (RE1), and RedEdge-2 (RE2). The best spectro-temporal features for SAR data are the 10% and 90% quantiles of VH backscatter. The selected feature results describe the phenology of paddy growth during flooding, maximum vegetative and bare land (post-harvest). The spectro-temporal features fusion of optical and SAR data increased the classification accuracy to 95,06±0,50%."

"Penelitian baru-baru ini yang menggunakan mikroskopi pump-probe pada material Sr$_{1-y}$NbO$_{3+\delta}$ menunjukkan kemampuan optical-switching yang mengarah kepada reduksi reflektansi hingga mendekati 100 %. Pada studi ini, kami mengajukan model sederhana untuk menjelaskan fenomena ini. Kami berhipotesis bahwa reduksi reflektansi ini disebabkan oleh efek korelasi yang muncul akibat interaksi elektron-elektron seiring dengan berkurangnya pengisian elektron pada pita konduksi karena tereksitasi ke pita yang lebih tinggi sepanjang waktu pump-ON. Di sini, kami memodelkan sistem material menggunakan model Hubbard satu-dimensi. Model ini kemudian diselesaikan dengan menggunakan metode fungsi Green dalam teori iterasi perturbasi termodifikasi (MIPT) untuk mempertahankan ketergantungan terhadap frekuensi pada self-energy. Hal ini penting karena self-energy ini memanifestasi hamburan elektron-elektron yang merupakan proses dinamis. Fungsi Green self-consistent yang diperoleh kemudian digunakan untuk menghitung fungsi respon optis dan reflektansi sebagai fungsi frekuensi foton. Terakhir, kami menampilkan nilai reflektansi pada frekuensi probe sebagai fungsi waktu dan membandingkannya dengan data eksperimen.

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A recent experimental study of pump-probe microscopy on material Sr$_{1-y}$NbO$_{3+\delta}$ shows an optical switching that leads to the reflectance reduction up to nearly 100 %. In this study, we propose a simple model to explain this phenomenon. We hypothesize that the reflectance reduction is caused by correlation effects arising from the electron-electron interaction accompanying the decrease of electron filling in conduction band as the electrons are excited to the higher band during pump-ON period. Here, we model the system using the one-dimensional Hubbard model. We solve this model using Green function method within modified iterated perturbation theory (MIPT) to retain the frequency dependence in the self energy. This is important since the self energy manifests the electron-electron scattering which is a dynamical process. The obtained self-consistent Green function is then used further to calculate the optical response function and the reflectance as a function of photon frequency. Finally, we plot the reflectance value at the probe frequency as a function of time and compare it to the experimental data."