Hasil Pencarian  ::  Simpan CSV :: Kembali

"ABSTRAKThe design and construction of eight-bit tune delay autocorrelator is discussed, suitable for use in photon correlation experiments. The sampling time of the correlator can be varied from 1 usec to 100/usec, devide into a number ( typically 256 ) channels (time interval). The instruments records the number of pulses occuring in each sampling time and is stored in location memory in a RAM-BANK. The data is stored in binary form,the data can be converted to analog form by digital to analog converter and is displayed on an oscilloscope."

"Detektor yang baik merupakan divais yang mampu bekerja pada frekuensi yang lebar, peka terhadap foton yang datang dan tidak menimbulkan derau yang mengganggu dalam proses komunikasi maupun dalam bidang instrumentasi.Untuk maksud tersebut dipilih jenis fotodioda jenis p-i-n dengan bahan aktif semikonduktor GaInAsP sebagai campuran empat macam bahan semikonduktor dari komposisi III dan V pada tabel periodik kimiawi.Dalam tesis ini dibahas tentang perhitungan dan analisa karakteristik fotodioda p-i-n, dari analisa diketahui bahwa hal ini sangat dipengaruhi aleh ketebalan lapisan yang atas (p+), sedangkan lapisan i (intrinsik) pada ketebalan tertentu sampai maksimum tidak mengalami peningkatan effisiensi, disamping itu unjuk kerja fotodioda secara umum sangat dipengaruhi pula oleh nilai resistansi bebannya.A good device for detector should operate at. wide band range, and sensitive to incident photon and produce low noise in both fields of communication and instrumentation systems. For that purpose the device used a type of p-i-n photodiode which contains active layers as quaternary of 111 and V compound in periodic system.

This thesis describes design and analysis of p-i-n photodiode to be used as a laser detector for )..= 1,.28 wiz . The Result show that the thickness of first (p+) and second (z) layer will limit the external efficiency of the detector, and also the load resistance will effect influence the performance of the detector."

"A material study for cathode tube of side window Geiger-Muller detector was carried out. Aim of the study is determine the counting correction factor to the absorpsion gamma radiation, so the type and thickness of materials tube can be sutled...."

"Telah dipelajari dan dikembangkan sebuah model sederhana untuk reaksi fotoproduksi η pada nukleon yaitu model isobar dengan menggunakan formalisme amplitudo transversal pada kerangka pusat massa. Fotoproduksi dianalisis pada energi foton Lab. antara 0.8-1.2 GeV. Reaksi fotoproduksinya adalah γ N → η N. Amplitudo yang ditinjau melibatkan kanal-s, kanal-t dan kanal-u pada suku Born dan resonan. Perhitungan observable yang ditinjau adalah penampang lintang differensial, penampang lintang total, dan polarisasi foton. Hasil penelitian ini menunjukkan seberapa besar kontribusi dari amplitudo transisi pada kanal-s, kanal-t dan kanal-u dari suku Born dan resonan pada proses perhitungan data observable.

---

A simple model for h photoproduction have been studied and developed in this research named isobaric model using transversal amplitudes formalism in the center of mass system. Photoproduction is analyzed in foton Lab. energy 0.8-1.2 GeV. The considered reaction is γN → ηN. Amplitudes consist of s channel, t channel and u channel in Born term and resonance term. Observable that we consider are differential cross section, total cross section and photon polarization. The result of this research is to show how large the contribution of transition amplitudes in channel-s, t-channel and channel-u from Born term and resonance term in the calculation of the observable data."

"Dalam paper ini akan dipaparkan langkah-langkah desain dan realisasi tranceiver SFGPR pada frekwensi kerja 1- 2 GHz untuk aplikasi deteksi logam dalam tanah. Sebelum prototip SFGPR diuji, dilakukan proses kalibrasi hubungan langsung untuk kalibrasi fasa dan pulsa monocycle. Setelah proses kalibrasi selesai, prototip SFGPR (Stepped Frequency Ground Penetrating Radar) ini kemudian diuji untuk mendeteksi silinder logam yang ditanam pada kedalaman 5 cm dibawah tanah dalam suatu kotak tanah nonhomogen berukuran 25 cm x 75 cm x 10 cm. Dari hasil kalibrasi dan uji deteksi silinder logam diperoleh kesimpulan bahwa, prototip SFGPR dapat bekerja dengan baik sesuai spesifikasi yang telah ditetapkan.

---

Design and Implementation of 1-2 GHz Stepped Frequency GPR for Buried Metal Detection. In this paper, we describe the design and realization steps of 1 ? 2 GHz SFGPR (Stepped Frequency Ground Penetrating Radar) transceiver for metal detection under the ground. Before using prototyped GPR for detecting the metal under the ground, several of calibration processes must be performed, namely phase calibration and monocycle pulse waveform calibration. After completing the calibrations, this prototyped GPR would be ready for detecting a hidden object such as a metal plate 5 cm under the ground in our small test range size 25 cm x 75 cm x 10 cm. From the calibration and detection results, we concluded that the prototyped SFGPR passed the technical specifications of the design and could perform the metal detection under the ground with high SNR."

"A new microwave - based transesterification reactor for converting vegetable oils to biodiesel has been developed and tested. The reactor consists of a microwave generator, microwave, waveguide and reaction tube that are compacted in small space. The transesterification of biodiesel feedstocks is performed in the reaction tube that is spatially an extention of the microwave waveguide. Using this scheme, the microwave energy is accumulated in narrow space such that it can be efficiently absorbed by the biodiesel feedstocks. The prototype have been tested by performing the transesterification of biodisel feedstocks, consisting of 80 % cooking oil, 20% of methanol and 1% of potassium hydroxide (KOH). We found that the physical properties of biodiesel product satisfies the SNI standard. The preliminary estimation of the electrical energy consumption yields a value of 0.04 kw/liter of biodiesel feedstock, or correspondingly 40% lower than that consumed by conventional method. Due to compactness of the reactor and low electrical consumption, we believe that this scheme can be further developed and applied for supporting the biodiesel industry in Indonesia. We therefore suggest the development of the microwave - based biodiesel pilot plant at a small to medium entrepreneur or home industry level."