Judul: Effectiveness of Rope-Assisted Logging  Techniques in Private Forests KOSTAJASA Central Java
Abstrak: Penebangan hutan rakyat dengan pola tanam agroforestri memerlukan teknik khusus agar tidak merusak tegakan tinggal. Salah satu teknik penebangan yang digunakan di hutan rakyat dengan pola tanam agroforestri adalah teknik penebangan dengan bantuan tali. Teknik ini mengarahkan pohon agar tumbang ke arah yang ditentukan. Penelitian ini dilakukan di empat petak tebang di hutan rakyat KOSTAJASA, Jawa Tengah. Tujuan dari penelitian ini adalah mengukur efektivitas penebangan pohon dengan bantuan tali. Indikator efektivitas teknik penebangan yang digunakan pada penelitian ini adalah kesalahan arah rebah, pohon tersangkut, dan unusan. Hasil penelitian menunjukkan bahwa persentase kesalahan arah rebah 44%, pohon tersangkut 29%, dan unusan 27%. Hasil penelitian ini merekomendasikan perlunya pelatihan bagi regu tebang agar kesalahan arah rebah, pohon tersangkut, dan terjadinya unusan dapat dikurangi.
Keyword: efektivitas, hutan rakyat, penebangan terarah, teknik tali

Judul: Productivity and Cost of Felling with Rope Technique at Agroforestri Private Forest in Probolinggo, East Java
Abstrak: Jarak tanam yang rapat dan batas lahan yang sempit menyebabkan risiko tingkat kerusakan tanaman bawah akibat kegiatan penebangan konvensional di hutan rakyat agroforestri cukup tinggi, sehingga diperlukan teknik penebangan yang dapat mengurangi kerusakan tanaman bawah. Teknik penebangan sandat digunakan oleh masyarakat untuk mengatasi hal tersebut. Tujuan penelitian adalah menganalisis produktivitas dan biaya penebangan teknik sandat pada hutan rakyat agroforestri. Analisis waktu dan elemen kerja berbasis video. Produktivitas didapatkan melalui volume dan waktu kerja yang dihasilkan setiap tahapan. Biaya didapatkan dari hasil wawancara dengan regu penebang untuk menentukan biaya tetap dan biaya variabel. Tahapan teknik penebangan sandat terdiri atas pemasangan sandat, penebangan, dan pembagian batang. Produktivitas pada tahapan pemasangan sandat, penebangan, dan pembagian batang berturut-turut adalah sebesar 11,80 m3/jam, 3,77 m3/jam, dan 5,33 m3/jam. Biaya per unit yang dikeluarkan pada tahapan pemasangan sandat, penebangan, dan pembagian batang berturut-turut adalah sebesar Rp2.600,63/ m3, Rp11.875,65/ m3, dan Rp10.699,34/m3., Close planting distances and narrow land boundaries cause the risk of damage to bottom crops due to conventional felling activities in agroforestry private forests being quite high, so felling technique are needed to solve it. Rope felling technique are used by communities to overcome this problem. The study aimed to analyze the productivity and cost of felling with rope technique in agroforestry private forests. The video-based analysis uses to determine time and work elements. Productivity is obtained through the volume and time of work produced by each stage. Costs are obtained from interviews with logger teams to determine fixed costs and variable costs. The stages of the felling with rope technique consist of rope installation, felling, and bucking. Productivity at the stages of rope installation, felling, and bucking was 11,80 m3/hour, 3,77 m3/hour, and 5,33 m3/hour. The cost per unit incurred at the stages of rope installation, felling, and bucking is Rp2.600,63/m3, Rp11.875,65/m3, and Rp10.699,34/m3.
Keyword: cost, felling, productivity, rope technique, working time

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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