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Ditemukan 2 dokumen yang sesuai dengan query
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Palupi, Maharani Ratna
Studi pengaruh perforasi terhadap koefisien absorpsi bunyi pada material gipsum = Study of the influence of perforation to the sound absorption coefficient of gypsum material
"[ABSTRAK
Telah dilakukan penelitian tentang pengaruh diameter perforasi terhadap koefisien
absorpsi bunyi pada material gipsum secara eksperimen dengan menggunakan
metode pengukuran yang tercantum dalam ISO 354-1985. Sampel divariasikan
terhadap kondisi tanpa perforasi dan terhadap diameter perforasi yaitu 0,8 mm, 1,2
mm, 2 mm, 4 mm, 6 mm, 8 mm, 10 mm dan 12 mm. Ada dua konfigurasi sampel
yang diteliti, yaitu sampel lapis tunggal (Sampel T) dan sampel sandwich (Sampel
S). Hasil penelitian menunjukkan adanya peningkatan koefisien absorpsi bunyi
hingga 27,97% seiring dengan penambahan diameter perforasi terutama di
frekuensi 125 Hz, 250 Hz, dan 500 Hz. Kenaikan koefisien absorpsi bunyi juga
terjadi pada saat diberikan sisipan rockwool di antara dua panel gipsum. Kedua
konfigurasi sampel dengan diameter perforasi 12 mm bisa digunakan sebagai
pilihan bahan penyerap bunyi untuk pengendalian bunyi di frekuensi 125 Hz, 250
Hz, dan 500 Hz.
ABSTRACT
Investigation on the influence of the perforation diameter to the sound absorption
coefficient in the gypsum material has been conducted experimentally by using
measurement methods in ISO 354-1985. The samples were varied on the condition
perforation. Perforation diameter about none, 0.8 mm, 1.2 mm, 2 mm, 4 mm, 6 mm,
8 mm, 10 mm and 12 mm. There were two configurations of samples, namely a
single-layer samples (Sample T) and sandwich samples (Sample S). The results
show the increasing in sound absorption coefficients up to 27,97% along with the
addition of diameter perforations, especially in the frequency of 125 Hz, 250 Hz,
and 500 Hz. The increasing in sound absorption coefficient also occur during
insertion of rockwool between two gypsum panels. Both sample configuration with
12 mm diameter perforation can be used as a sound absorbent material to control
sound at frequencies of 125 Hz, 250 Hz, and 500 Hz., Investigation on the influence of the perforation diameter to the sound absorption
coefficient in the gypsum material has been conducted experimentally by using
measurement methods in ISO 354-1985. The samples were varied on the condition
perforation. Perforation diameter about none, 0.8 mm, 1.2 mm, 2 mm, 4 mm, 6 mm,
8 mm, 10 mm and 12 mm. There were two configurations of samples, namely a
single-layer samples (Sample T) and sandwich samples (Sample S). The results
show the increasing in sound absorption coefficients up to 27,97% along with the
addition of diameter perforations, especially in the frequency of 125 Hz, 250 Hz,
and 500 Hz. The increasing in sound absorption coefficient also occur during
insertion of rockwool between two gypsum panels. Both sample configuration with
12 mm diameter perforation can be used as a sound absorbent material to control
sound at frequencies of 125 Hz, 250 Hz, and 500 Hz.]"
2016
T44954
UI - Tesis Membership  Universitas Indonesia Library
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Aldo Rosario
Rancang Bangun Prototipe Sistem Pencitraan Near-Infrared Indocyanine Green (ICG) Rendah Biaya dengan Analisis Karakteristik Filter dan Pengolahan Hasil Citra = Low Cost Near-Infrared Indocyanine Green (ICG) Imaging System Prototype Design with Filter Characteristics Analysis and Image Processing
"Pencitraan fluoresens near-infrared (NIR) merupakan metode pencitraan yang menjanjikan dalam dunia kedokteran dengan menggunakan kamera khusus dan kontras agen indocyanine green (ICG). Teknik ini menawarkan keamanan dalam penggunaannya, resolusi yang tinggi, dan sensitivitas yang baik sehingga kebutuhan akan perangkat pencitraan ini terus meningkat. Beberapa studi melaporkan penggunaan metode pencitraan fluoresens NIR dalam berbagai aplikasi medis baik menggunakan perangkat komersial, maupun perangkat rakitan sendiri. Tujuan dari penelitian ini adalah merancang sistem pencitraan fluoresens near-infrared menggunakan filter plastik mika dan kamera IP CCTV serta metode subtraksi dalam mendeteksi fluoresens ICG.
Karakterisasi filter plastik mika menggunakan spektrometer dilakukan untuk mengetahui respons filter dan menentukan kombinasi warna paling efektif. Perancangan prototipe menggunakan kamera IP CCTV yang dimodifikasi sebagai komponen utama dalam mengambil citra. Metode subtraksi yang digunakan mampu menjadi alternatif dalam mendeteksi fluoresens yang dihasilkan ICG dengan mengurangi piksel dari 2 buah gambar dengan kondisi berbeda. Kombinasi filter yang paling efektif dalam meredam cahaya tampak adalah merah-kuning-hijau-biru (MKHB) yaitu pada panjang gelombang 400 nm – 680 nm dengan transmitansi sebesar 64,55%. Rata-rata koefisien absorpsi pada filter plastik mika MKHB sebesar 9,87 cm-1 pada panjang gelombang 830 ± 20 nm. Keseluruhan prototipe berhasil dibuat dan memiliki resolusi yang masih dapat diterima serta biaya produksi sebesar Rp512.000,00.
......
Near-infrared (NIR) fluorescent imaging is a promising imaging method in medicine using a special camera and indocyanine green (ICG) contrast agent. This technique offers safety in use, high resolution, and good sensitivity so that the need for this imaging device will continue to increase. Several studies have reported the use of NIR fluorescent imaging methods in various medical applications using either commercial devices or handmade devices. The aim of this research is to design a near-infrared fluorescent imaging system using mica plastic filters and IP CCTV cameras and subtraction methods to detect fluorescent ICG.
Characterization of mica plastic filters using a spectrometer was carried out to determine the response of the filter and determine the most effective color combination. The prototype design uses a modified CCTV IP camera as the main component in taking images. The subtraction method used can be an alternative in detecting fluorescence produced by ICG by subtracting pixels from 2 images with different conditions. The most effective filter combination in reducing visible light is red-yellow-green-blue, which is at a wavelength of 400 nm – 680 nm with a transmittance of 64,55%. The average absorption coefficient on MKHB plastic mica filters was 9,87 cm-1 at a wavelength of 830 ± 20 nm. The entire prototype was successfully made and has an acceptable resolution and a production cost of 512,000.00 IDR."
Depok: Fakultas Teknik Universitas Indonesia, 2023
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UI - Skripsi Membership  Universitas Indonesia Library