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: Techniques, Productivity, and Costs of Tree Felling in Private Forests Kostajasa, Central Java
Abstrak: Penebangan pohon di hutan rakyat memerlukan teknik yang tepat untuk meminimalkan kerusakan yang ditimbulkan dan sesuai dengan kondisi lokal. Penelitian ini bertujuan untuk mengidentifikasi teknik-teknik penebangan pohon, menghitung produktivitas, dan biaya penebangan di hutan rakyat Kostajasa. Penelitian ini dilakukan di empat lahan hutan rakyat di Kostajasa, yang mana setiap lahan dikerjakan oleh tim penebang yang berbeda. Pengukuran waktu kerja dilakukan menggunakan metode null stop. Produktivitas dihitung dengan membagi volume pohon berdiri dengan waktu kerja. Data biaya diperoleh melalui wawancara dengan tim penebang dan data sekunder. Hasil penelitian menunjukkan bahwa teknik penebangan yang digunakan di hutan rakyat Kostajasa adalah bervariasi, yaitu teknik tebang konvensional, teknik penebangan dengan bantuan tali, dan teknik tebang dengan pemangkasan dahan. Produktivitas penebangan di lahan 1, 2, 3, dan 4 berturut-turut adalah 2,9 m3/jam; 2,5 m3/jam; 8,9 m3/jam; dan 6,8 m3/jam. Biaya penebangan per unit untuk lahan 1, 2, 3, dan 4 berturut-turut sebesar Rp 22.435/m3; Rp 28.854/m3; Rp 7.987/m3; dan Rp 10.087/m3., Forest harvesting in private forests requires appropriate techniques to minimize the damage caused and suitable with local situations. This study aims to identify tree felling techniques, calculate productivity, and costs in the Kostajasa private forest. This study was conducted in four areas of the Kostajasa private forest, each of which was worked on by different team of loggers. Working time was measured using the null-stop method. Productivity was obtained through a comparison between the volume of standing tree and time of work produced. Costs were obtained from direct interviews with the felling team on each land. The results of the study show that the logging techniques used in Kostajasa private forests are varied, namely conventional logging techniques, logging techniques with the help of ropes, and cutting techniques with pruning branches. The productivity produced on land 1, 2, 3, and 4 is, respectively, 2,9 m3 /hour; 2,5 m3 /hour; 8,9 m3 /hour; and 6,8 m3 /hour. With the cost per unit used on land 1, 2, 3, and 4, respectively, amounting to Rp 22.435/m3; Rp 28.854/m3; Rp 7.987/m3; and Rp 10.087/m3.
Keyword: cost, logging, private forests, productivity, 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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