Judul: Productivity Felling and Bucking of Rasamala at BKPH Cikawung KPH Sukabumi
Abstrak: Langkah pertama pada kegiatan pemanenan kayu yang harus dilakukan adalah penebangan pohon. Proses ini sangat penting karena adanya kesalahan dalam proses ini dapat mengakibatkan penurunan produktivitas kayu. Produktivitas kayu penting untuk diperhatikan mengingat hal tersebut digunakan sebagai penentu atau perhitungan upah. Salah satu analisis yang dapat digunakan untuk menghitung produktivitas kayu adalah dengan menghitung waktu kerja dengan volume tebangan yang dihasilkan. Kayu rasamala merupakan salah satu kayu yang banyak digunakan dalam berbagai hal, seperti dalam bangunan rumah. Atas dasar tersebut, penelitian ini bertujuan untuk menganalisis besarnya produktivitas penebangan kayu menggunakan chainsaw di BKPH Cikawung, menganalisis pengaruh volume kayu dan diameter terhadap produktivitas penebangan, dan menganalisis besarnya biaya penebangan menggunakan chainsaw di BKPH Cikawung KPH Sukabumi. Produktivitas penebangan rasamala yang didapatkan pada waktu efektif sebesar 3,65 m3 /jam dan pada waktu aktual sebesar 3,51 m3 /jam. Hasil regresi antara volume kayu dengan produktivitas penebangan menunjukkan bahwa volume kayu berpengaruh signifikan terhadap produktivitas penebangan, dan begitu juga dengan regresi antara diameter dan produktivitas penebangan. Kata kunci: biaya penebangan, penebangan, pembagian batang, produktivitas, waktu kerja, Tree felling is an important step in harvesting wood, as it’s the first activity conducted. It is imperative to not make any mistakes as mistakes conducted in this step could decrease timber productivity. It is also imperative to keep an eye on timber productivity as it is used as a determinant or calculating wages. One of the analysis that can be used to calculate wood productivity is to calculate the working time with the volume of felling produced. Rasamala wood is one of the woods that is widely used in various ways, such as in building houses. On this basis, this study aims to analyze the productivity of logging using a chainsaw at BKPH Cikawung, to analyze the effect of log volume and diameter on logging productivity, and to analyze the cost of logging using a chainsaw at BKPH Cikawung KPH Sukabumi. The productivity of felling Rasamala trees was measured at 3,65 m3 /hour and the actual time at 3,51 m3 /hour. Regression analysis between volume and productivity and between diameter and productivity reported a statistically significant results of both regressions. Keywords: bucking, felling, harvesting cost, productivity, time work
Keyword: bucking, felling, harvesting cost, productivity, time work

Judul: Productivity, Cost Analysis, and Efficiency of Felling Activities at RPH Cipeundeuy KPH North Bandung, West Java
Abstrak: Proses pemanenan hutan merupakan hal penting dalam kegiatan produksi kayu bulat yaitu kegiatan penebangan dan bagi batang. Tujuan penelitian ini adalah mengetahui nilai produktivias, biaya penebangan, dan efisiensi pemanfaatan kayu pada jenis tegakan jati (Tectona grandis L.f) serta faktor volume kayu, waktu kerja, dan kelerengan di RPH Cipeundeuy KPH Bandung Utara. Produktivitas di RPH Cipeundeuy dibedakan atas perbedaan topografi yakni landai dan curam. Hasil penelitian menunjukkan produktivitas efektif lebih besar dibandingkan produktivitas aktual dan standar sebesar 4,07 m3/jam dan 4,06 m3/jam dengan volume rataan setiap topografi yakni landai sebesar 0,64 m3 dan curam 0,61 m3. Biaya penebangan di topografi landai lebih rendah (Rp 12.045/m3) dibandingkan di topografi curam (Rp 12.075/m3) dari hasil produktivitas terbesar. Faktor yang mempengaruhi produktivitas dan biaya penebangan sebesar 48,85% dan 88,49%. Efisiensi pemanfaatan kayu di RPH Cipeundeuy pada topografi landai dan curam memperoleh nilai persentase sebesar 92,35% dan 89,60%. Tingkat efisiensi tertinggi dipengaruhi oleh volume kayu yang telah dihasilkan yakni di topografi landai., The process of harvesting the forest is an important thing in the production of logs, namely felling and stem sharing. The purpose of this study was to determine the value of productivity, felling costs, and efficiency of wood utilization in teak stands (Tectona grandis L.f) as well as factors of wood volume, working time, and slope at Cipeundeuy RPH KPH North Bandung. Productivity at Cipeundeuy RPH is distinguished by topographic differences, namely sloping and steep. The results showed that the effective productivity was greater than the actual and standard productivity of 4,07 m3/hour and 4,06 m3/hour with an average volume of each topography, namely sloping 0,64 m3 and steep 0,61 m3. Felling costs in the sloping topography are lower (Rp 12.045/m3) than in the steep topography (Rp 12.075/m3) resulting in the highest productivity. Factors that affect productivity and felling costs are 48,85% and 88,49%, respectively. The efficiency of wood utilization in Cipeundeuy RPH on sloping and steep topography obtained percentage values of 92,35% and 89,60%, respectively. The highest level of efficiency is influenced by the volume of wood that has been produced, namely in sloping topography.
Keyword: cost, efficiency, felling, productivity, topography

Judul: Metrik Einstein (Anti-) Self-Dual Berdimensi Empat dengan Metode Cartan
Abstrak: Gravitational field equation can be formulated in differential forms (differential geometry), which describes gravity as a manifestation of the curvature of space-time. Curvature of space-time is characterized by a metric that satisfies the gravitational field equation. With differential forms it can be formulated the (anti-) self-dual Einstein equation, which is a modification of the Cartan structure in (anti-) self-dual basis. Calculation of (anti-) self-dual metric with (anti-) self-dual Einstein equation is simpler than the calculation using Christoffel symbols.
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