Judul: Estimating the Potential of Above-Surface Biomass in the Mbeliling Forest Area of East Nusa Tenggara Using Landsat 8 Satellite Imagery
Abstrak: Pemanasan global terjadi akibat akumulasi gas efek rumah kaca seperti CO2, CH4, NO2, HFCs, PFCs, dan SF6 di atmosfer. Hutan memiliki peran sebagai penyimpan dan penyerap karbon, hal ini sangat penting dalam mengatasi terjadinya pemanasan global yang diakibatkan oleh gas rumah kaca. Penelitian ini bertujuan menduga potensi biomassa menggunakan indeks vegetasi dan nilai digital Citra Landsat 8 serta membuat peta sebaran biomassa berdasarkan model pendugaan terbaik. Penghitungan biomassa lapangan menggunakan rumus allometrik. Model regresi terbaik dipilih berdasarkan parameter uji-F, nilai koefisien determinasi (R2), nilai koefisien determinasi terkoreksi (R2-adj) dan nilai RMSE. Model regresi Multiplikatif terpilih menjadi model terbaik dengan persamaan Y = 10^-1.576 x BAND6^-0.673 x BAND9^-1.176., Global warming occurs due to the accumulation of greenhouse gases such as CO2, CH4, NO2, HFCs, PFCs and SF6 in the atmosphere. Forests have a role as a carbon store and absorber, this is very important in overcoming global warming caused by greenhouse gases. This study aims to estimate the biomass potential using the vegetation index and digital values of Landsat 8 imagery and to create a biomass distribution map based on the best estimation model. Calculation of field biomass using the allometric formula. The best regression model was selected based on the F-test parameters, the value of the coefficient of determination (R2), the value of the corrected coefficient of determination (R2-adj) and the RMSE value. Multiplicative regression model was chosen to be the best model with the equation Y = 10^-1.576 x BAND6^-0.673 x BAND9^-1.176 .
Keyword: biomass, citra landsat 8, mapping, regression

Judul: Pendugaan Potensi Biomassa Atas Tegakan Jati (Tectona Grandis Linn. F) Menggunakan Citra Landsat 8 Di BKPH Wilangan Selatan, KPH Saradan
Abstrak: Landsat 8 merupakan satelit pemantau sumberdaya alam yang memiliki sensor Onboard Operational Land Imager (OLI) dan Thermal Infrared Sensor (TIRS) dengan 10 buah kanal multispektral dan satu buah kanal pankromatik. Penelitian ini bertujuan untuk merumuskan model pendugaan potensi biomassa berdasarkan nilai digital band dari Citra Landsat 8 dan nilai digital indeks vegetasi serta membuat peta sebaran potensi biomassa dari persamaan model terbaik. Perhitungan biomassa dilakukan dengan menggunakan persamaan alometrik. Pemilihan model terbaik dilakukan berdasarkan parameter uji-F, nilai koefisien determinasi terkoreksi (R2 adj) dan nilai RMSE. Hasil menunjukan bahwa model regresi terbaik, yaitu model eksponensial Y = e (28.24 – 0.00594 Band 5 + 0.00316 Band 6 – 21.88 TVI) dengan nilai R2 dan R2 adj paling besar yaitu 80.66 % dan 79.95 % dengan nilai RMSE paling kecil sebesar 0.598. Model regresi terbaik digunakan sebagai dasar dalam pembuatan peta sebaran biomassa. Hasil dari evaluasi akurasi menunjukan nilai overall accuracy sebesar 92.12 % dan kappa accuracy sebesar 87.64 % pada pemetaan dengan 3 kelas.
Keyword: biomassa, landsat 8, model penduga, pemetaan

Judul: Characterizations of low alloy steel sae 4422  plated with chromic acid (Cro3)
Abstrak: Characterizations of low alloy steel SAE 4422 plated with chromic acid (CrOrO3) was use Optical Microscopy (OM), Scanning Electron Microscopy (SEM), X-Ray Diffraction (XRD), RD),Energy Dispersive Analysis of X-Ray (EDAX), Hardness Test and Roughness Test. Microstructures analysis exhibits cracks and grain boundaries microcracks as a characteristics of chrome metal found at plating metal. Perlite and Ferrite as grains of steel found at base metal with grain boundaries around it. Phase analysis of plating metal appropriate to chrome metal with lattice constant (a) is 2.559 Å and phase analysis of base metal appropriate to iron ferrite with lattice constant (a) is 3.318 Å. Both plating and base metal have cubic system. Chemical analysis of plating metal at surface section exhibits that cracks area have highest value of carbon element compare with grains and grains boundaries area. While chemical analysis of base metal at cross section exhibits that perlite have highest value of carbon element compare with ferrite and grain boundaries. The hardness value of plating metal at surface section and cross section are 753 and 637 VHN. While, the hardness value of base metal and interface area at cross section are 205 and 373 VHN. The roughness value at measurement points of chrome surface for as received sample are 0.445 μm. Observation used Optical Microscopy and Scanning Electron Microscopy exhibits surface irregularities combine to form surface texture of plating metal at surface section.
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