Judul: Desain Dan Uji Kinerja prototipe Alat Pengupas Singkong (Manihot esculenta Crantz) Dengan Pisau Setengah Melingkar
Abstrak: Physical shape and size of cassava which is diverse causing the cassava peeler rarely to be developed, however for the cassava slicer has already a lot developed, therefore cassava peeler is needed. The cassava peeler on the previous research (Ubaidillah s. 2009)has the circular blade. The objective of this reseach is to create a type of circular half blade and to examine the tool. The test to peel the cassava skin using the first tool has average peeler velocity of 61.22 second/cassava. Looking at peeler velocity, first tools is quite slow, in the other hand, this tools can only peel cassava with fixed diameter about 5 cm. The test to peel the cassava skin using the second tool has average peeler velocity of 46.49 second/cassava. This second tools can peel cassava with a diameter of 5 – 8.5 cm or the diverse diameter. While the peeler that cassava farmer has done is using an ordinary blade with the average peel velocity of 17.75 second. The measurement of work load in the second peeler has using the heart rate tool. Damage level that usually hapen on ordinary blade is low level damage, first tool usually high level damage, and for second tool is low level damage.
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Judul: Design and Simulation of Red Beans External Peeler Machine with Spoke Type Beater
Abstrak: Rancangan mesin pengupasan polong kacang merah tipe dual roll dan sistem bantingan dinilai kurang efektif dikarenakan pengupasan untuk setiap polong hanya dilakukan satu kali. Penelitian ini bertujuan merancang dan menyimulasikan mesin pengupas kulit luar kacang merah tipe ruji. Penelitian dilakukan dengan pendekatan desain fungsional dan struktural yang terdiri dari tahap identifikasi masalah, perumusan konsep desain, analisis teknik, gambar teknik serta simulasi. Simulasi Finite Element Analysis (FEA) menunjukkan bahwa stress pada hopper sebesar 3% dari yield strength. Ruang pengupas mengalami defleksi maksimum sebesar 0,13 mm, sedangkan rangka mengalami defleksi 0,1 mm. Keduanya berada dibawah batas maksimum 2 mm. Hasil simulasi Discret Element Methode (DEM) pada hopper mampu mengalirkan polong dengan laju rata rata sebesar 0,0249 kg/s. Simulasi computational fluid dynamic (CFD) menunjukkan bahwa rancangan debit udara sebesar 0,5 m3/s pada ruang pengupas mampu memberi gaya dorong hingga 0,153 N, sementara pada ruang pemisah menunjukkan bahwa debit harus ditingkatkan dari 0,0171 m3/s menjadi 0,021 m3/s untuk memperoleh gaya dorong sebesar 0,004 N. Berdasarkan laju massa polong diperoleh kapasitas kerja mesin sebesar 89,64 kg/jam., The design of the dual roll type red bean pod peeling machine and rotary impact is considered less effective because the stripping for each pod is only done once. The purpose of this study was to design and simulate red bean external peeler machine with spoke type beater. The research was conducted with a functional and structural design approach consisting of problem identification, design concept formulation, technical analysis, engineering drawings and simulations. Finite Element Analysis (FEA) simulation shows that the stress on the hopper is 3% of the yield strength. The peeler chamber component experienced a maximum deflection of 0.13 mm, while the frame experienced a deflection of 0.1 mm. Both are below the maximum limit of 2 mm. The simulation results of the Discret Element Method (DEM) on the hopper were able to drain the pods at an average rate of 0.0249 kg/s. Computational fluid dynamic (CFD) simulations show that the designed air flowrate of 0,5 m3/s in the stripper chamber is able to provide a thrust of up to 0.153 N, while in the separator chamber it shows that the flowrate must be increased from 0,0171 m3/s to 0,024 m3/s to obtain a thrust of 0.004 N. Based on the mass rate of the pods obtained a working capacity of 89.64 kg/hour machine.
Keyword: computational fluid dynamic, discret element methode, finite element  analysis, kacang merah, pengupas polong

Judul: Pengaruh ENSO terhadap Variabilitas Ozon Total di Indonesia
Abstrak: Konsentrasi ozon total di atmosfer adalah jumlah ozon total yang ada di lapisan stratosfer dan troposfer yang lebih banyak merepresentasikan ozon stratosferik karena jumlahnya yang lebih banyak dibandingkan ozon troposferik. Ozon adalah salah satu gas aktif yang memiliki dampak besar terhadap keseimbangan radiasi dan iklim global. Penelitian ini bertujuan mengetahui variabilitas parameter suhu dan ketinggian geopotensial yang berkaitan dengan ozon total dan mengidentifikasi pengaruh fenomena ENSO terhadap jumlah ozon total di Indonesia. Data yang digunakan adalah data total kolom ozon, suhu, dan ketinggian geopotensial bulanan dari ERA5 dan indeks Nino 3.4 bulanan dari NOAA tahun 1996-2016. Hasil yang diperoleh dari analisis komposit adalah parameter suhu 100 mb dan ketinggian geopotensial 100 mb di lapisan stratosfer bawah pada saat El Nino mengalami anomali negatif, begitu pula dengan ozon, sedangkan pada saat La Nina menunjukkan pola yang terbalik, khususnya di Bulan Desember, Januari, dan Februari. Hasil analisis korelasi antara ozon total dengan indeks Nino 3.4 menunjukkan hasil koefisien korelasi pada musim kering (Mei-Oktober) berkisar -0.95 ≤ r ≤ 0.35 dan pada musim basah (November-April) berkisar -0.93 ≤ r ≤ 0.64 dengan sebagian besar korelasi bernilai negatif di seluruh wilayah Indonesia. Hasil tersebut menunjukkan bahwa adanya anomali positif dari suhu permukaan laut di wilayah Pasifik Timur (El Nino) akan menyebabkan penurunan ozon total, begitu pula sebaliknya., Total column ozone is the total amount of ozone in the stratosphere and troposphere layer, which represent more stratospheric ozone considering that it is more abundant than tropospheric ozone. Ozone is one of the active gases that has a major impact on the radiative forcing and the global climate. This study aims to determine the temperature and geopotential height parameters variability related to total ozone and to identify the effect of ENSO on the total amount of ozone in Indonesia. The data used are total column ozone, temperature, and geopotential height monthly data from ERA5 and monthly Nino 3.4 index from NOAA in 1996-2016. Using composite analysis, it found that temperature and geopotential height parameters in the lower stratosphere during El Nino will experience negative anomalies in line with negative anomalies ozone, while during La Nina shows an opposite pattern, especially in December, January, and February. The results of correlation analysis between total column ozone and Nino 3.4 index showed a significantly negative correlation coefficient almost all over Indonesia, with ranges -0.95 ≤ r ≤ 0.35 in the dry season, and -0.93 ≤ r ≤ 0.64 in the wet season. It indicates that the presence of a positive anomaly of sea surface temperature in the East Pacific region (El Nino) will cause a decrease in total ozone and vice versa.
Keyword: ERA5, ketinggian geopotensial, suhu, ozon total