Judul: Kalibrasi alat pengukur kadar air digital untuk produk biji-bijian
Abstrak: Effesiensi pengolahan pertanian adalah sangat perlu dan penting sekali dalam mencari terobosan-terobosan baru atau inovasi dalam setiap tahap pengolahan komoditas pertanian. Pengendalian mutu merupakan suatu tindakan berencana agar segala pelaksanaan proses produksi dapat mencapai tingkatan mutu yang sudah ditetapkan dengan biaya seekonomis mingkin (Hasan, 1976). Selain terobosan-terobosan inovasi pengolahan, peralatan-peralatan pengolahan harus dipelihara dengan baik agar alat-alat ukur yang digunakan dapat dipercaya kebenaran dan ketepatan hasil pengukuran (Soedja'I : 1980; Pusat Pengujian Mutu Barang, 1982)
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Judul: Disain prototipe alat pengukuran kadar air biji-bijian didital dengan sistem kapasitas
Abstrak: Tujuan penelitian ini adalah mendisál alat pengukur kadar air digital dengan sistem kapasitansi, melakukan uji coba karakteristik dan kemampuan instrumen serta kalibrasi dan menguji ke- mampuan sensor dengan beberapa cara terutama sensor secara lang- sung dan sensor dengan sistem jembatan wheatstone. Pengujian instrumen dilakukan dengan melihat hubungan antara kadar air biji-bijian dengan tegangan keluaran yang dihasilkan oleh instrumen. Hasil pengujian menunjukkan bahwa keeratan hubungan antara kadar air biji-bijian dengan tegangan keluaran pada metoda secara langsung lebih erat dibandingkan dengan metoda jembatan wheatstone, atau dengan kata lain bahwa metoda secara langsung lebih baik untuk dipakai sebagai metoda pengukuran kadar air dibandingkan dengan metoda jembatan wheatstone. Alat pengukur kadar air digital dengan sistem kapasitansi yang dibuat mempunyai kemampuan untuk mengukur kadar air beras pada tingkat kadar air 10.33% bb sampai 20.33% bb dengan kepe- kaan pengukuran pada selang 10.33% bb- 16.00% bb sebesar 0.1 volt/persen dan pada selang 16.00% bb- 20.33% bb sebesar 0.75 volt/persen. Pada pengukuran kadar air gabah alat mempunyai ke- mampuan mengukur kadar air pada tingkat kadar air 5.36% bb sam- pai 27.01 % bb dengan kepekaan pengukuran pada selang 5.36% bb- 16.00 % bb sebesar 0.04 volt/persen dan pada selang 16.00 % bb- 27.01% bb sebesar 0.54 volt/persen. Untuk mengukur kadar air jagung alat mempunyai kemampuan mengukur kada air pada tingkat kadar air 7.51% bb sampai 24.30% bb dengan kepekaan pengukuran pada selang 7.51% bb 13.68% bb sebesar 0.09 volt/persen dan pada selang 14.15% bb 24.30% bb sebesar 0.59 volt/persen. Untuk mengukur kadar air kedelai alat mempunyai kemampuan mengukur kadar air pada tingkat kadar air 10.00% bb sampai 16.00 % bb dengan kepekaan sebesar 0.8 volt/persen dan pada pengukuran kadar air kacang hijau alat mempunyai kemampuan mengukur pada tingkat kadar air 6.63 % bb sampai 14.00 % bb dengan kepekaan pengukuran sebesar 0.19 volt/persen…dst
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Judul: Thermal Characteristics and Dynamics of Tropical Cyclone over Western North Pacific Ocean: A Case Study of Typhoon Songda (Chedeng) 2011
Abstrak: The frequent occasion of Tropical Cyclone (TC) over Western North Pacific (WNP) Ocean lies from 10˚N to 26˚N and 121˚E to 170˚E. Sources of TC development come from warm ocean temperature where latent heat is released during condensation processes and subsequently concentrated in the boundary layer. Relative humidity at 850-700 hPa is responsible to produce the most intense storm. Meanwhile, weak vertical wind shear between 850-200 hPa is one of the dynamical factors that lead to the development of TC. Pressure level of 850-200 hPa is chosen to minimize the thermodynamic effect in the lower troposphere. Typhoon Songda (Chedeng in the Philippines) or TSC lasted from May 18th to 30th, 2011 and strengthened into powerful Super Typhoon stage between May 24th and 27th. Long curving track and the exhibition of all sequences of TC life cycle, TSC is then considered as an ideal case of TC. The objective of the study with case of TSC is to investigate the role of thermal characteristics and dynamics on TC intensity. The research is carried out by using Advanced Research of Weather Research and Forecasting model (WRF ARW model) version 3.3. Two domains are employed in the model. The first domain situate from 02˚N to 40˚N and 118˚E to 149˚E and cover spatial resolution () of 33.1 km. The second domain situate from 09˚N to 27˚N and 119˚E to 132˚E with of 11 km. Timestep of the model () is 120 seconds. The model is supported by the following physical parameterization, i.e., Yonsei University Scheme (YSU) in the boundary layer, Kain-Fritsch scheme (KF) in the cumulus, and WRF Single-Moment 3-class scheme in the microphysics. Initial meteorological condition prior to the formation of the cyclone is generated using WRF ARW standard-release model. Sensitivity of the model output is obtained from a selected single-parameter change scenarios, namely, 10 % to 20 % decrease and increase of wind shear initial data at 850-200 hPa, and by 10 % to 20 % decrease of relative humidity initial data at 850-700 hPa. The result showed that the negative correlations between wind shear and intensity are found in wind shear scenarios. Wind shears of 10 ms-1 which lead to strengthening of the wind intensity in the early period of Typhoon development are found in wind shear scenarios. The effect of wind shear changes on wind intensity is statistically significant in the 20 % wind shear scenarios. During mature stage, weak wind intensity occurred when wind shear increase as given in the WRF standard-release and the 20 % decreasing scenario. Different situation is found in the 20 % increasing scenario where wind shear tend to weak and lead to strong wind intensity at this stage. Meanwhile, the reduction of moisture supply at 850-700 hPa resulting from 20 % decreasing relative humidity play a major role in the weakening of wind intensity and reduces mechanical energy of the cycle process as much as 300 J kg-1.
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