Judul: Penilaian Postur Kerja Menggunakan Analisis REBA dan RULA pada Kegiatan Penebangan Jati Masak Tebang
Abstrak: Salah satu kegiatan pemanenan hutan adalah pemanenan jati masak tebang yang terdiri dari kegiatan penebangan, pembagian batang, penyaradan, muat bongkar, dan pengangkutan. Kegiatan pemanenan jati memiliki risiko yang membahayakan kesehatan dan keselamatan pekerjanya seperti risiko Musculoskeletal Disorders (MSDs). Karena itu diperlukan tindakan pencegahan agar mengurangi risiko MSDs dalam kegiatan penebangan jati dengan analisis postur kerja ekstrem dan aksi ergonomi. Postur kerja esktrem dipilih melalui analisis Range of Motion (ROM), yang kemudian dianalisis risiko postur kerja dengan metode Rapid Entire Body Assessment (REBA) dan Rapid Upper Limb Assessment (RULA). Hasil analisis menunjukkan bahwa segmen tubuh yang sangat berpengaruh terhadap risiko MSDs yang diterima oleh operator penebangan jati ialah bagian punggung, lengan atas, serta besaran beban yang diterima. Aksi ergonomi yang dapat dilakukan untuk mengurangi risiko MSDs berupa menggunakan postur kerja rekomendasi, menghindari postur membungkuk dan mengganti dengan postur berlutut, menggunakan alat chainsaw yang memiliki beban lebih ringan dan pemeliharaan alat yang baik, serta adanya waktu istirahat aktif bagi operator., One of the forest harvesting activities is teak harvesting that consists of felling, trunk dividing, skidding, loading and unloading, and transportation. Teak harvesting activities have risks that endanger the health and safety of their workers, such as the risk of Musculoskeletal Disorders (MSDs). Therefore, preventive measures are needed to reduce the risk of MSDs in teak felling activities by analyzing extreme work postures and ergonomic actions. Extreme work postures are selected through Range of Motion (ROM) analysis, then followed by analyzing work posture risk using the Rapid Entire Body Assessment (REBA) and Rapid Upper Limb Assessment (RULA) methods. The results of the analysis show that the body segments that greatly influence the risk of MSDs received by operators of teak felling are the back, upper arms, and the amount of load received. Ergonomic actions that can be taken to reduce the risk of MSDs include using recommended work postures, avoiding slouching postures and replacing them with kneeling postures, using chainsaws that have a lighter load and good maintenance, as well as having active rest periods for operators.
Keyword: MSDs, REBA, RULA, teak felling, work posture

Judul: Risk Analysis of Chainsaw Operator Work Posture in Bucking Activities of Teak Stands and Cutting Using REBA and RULA Methods
Abstrak: Pekerjaan dibidang kehutanan merupakan jenis pekerjaan berbahaya yang memiliki berbagai kendala seperti lingkungan kerja yang sulit, pekerjaan fisik yang berat yang sering melebihi batas kapasitas pekerja hutan, dan risiko kecelakaan kerja yang tinggi. Penelitian ini bertujuan untuk mengidentifikasi tingkat risiko gangguan otot (Musculoskeletal disorders/MSDs) pada kegiatan pembagian batang dan memberikan rekomendasi perbaikan postur kerja dengan tingkat risiko yang lebih rendah. Metode yang digunakan dalam menganalisis postur kerja yaitu ROM, RULA, dan REBA. Hasil analisis menunjukkan bahwa sebagian besar postur kerja pada elemen kerja dalam kegiatan bucking memiliki level risiko sedang hingga tinggi sehingga harus dilakukan tindakan perbaikan. Aksi ergonomi yang dapat dilakukan dalam mengurangi gangguan pada sistem muskuloskeletal adalah mengurangi sudut yang menyebabkan postur janggal. Selain itu, pengurangan beban yang diterima oleh pekerja, melakukan pemeliharaan alat secara berkala dan meningkatkan frekuensi beristirahat dapat mengurangi risiko kelelahan otot., Work in the forestry sector is a hazardous occupation with numerous hazards, including a challenging working environment, intense physical labor that frequently surpasses forest employees' capacity limits, and a significant risk of workplace accidents. The goal of this study is to determine the risk of muscular diseases (musculoskeletal disorders/MSDs) in trunk division tasks and to make recommendations for optimizing work posture with a reduced risk. ROM, RULA, and REBA are three approaches for assessing labor postures. The analysis reveals that the majority of work postures on the work element in bucking activities pose a moderate to high risk, necessitating corrective action. Reducing the angle that creates difficult postures is an ergonomic measure that can be made to decrease musculoskeletal system problems. Muscle tiredness can also be reduced by reducing the burden carried by workers, performing regular equipment maintenance, and increasing the frequency of rest.
Keyword: Bucking, MSDs, REBA, RULA

Judul: Hybrid solar cells of ZnO nanoparticles/chlorophyll was modified metal ions (Zn2+ and Cu2+ )
Abstrak: Zinc Oxide (ZnO) is a n-type semiconductor with a wide the energy band (Band Gap) is 3.37 eV at room temperature and 3.34 eV at low temperature with a large exiton binding energy is 60 meV. ZnO has been synthesized by hydrothermal method, resulting in a decrease in particle size over the duration of the hydrothermal changes. Crystallographic structure of ZnO were characterized using XRD, has shown the characteristic pattern of a hexagonal wurtzite structure, the crystallite size increases to changes in particle size. Changes in particle size has also led to a change in the absorption peak of ZnO as has been demonstrated posted under test using the optical properties of UV-Vis spectrophotometer. Changes of this uptake has also led to changes in the energy band gap, which increases its band gap energy of the particle size. In electronic applications, especially in solar cells. Chlorophyll is considered less effective, because of their very nature are easily degraded as a result of several reactions which are acid, lighting and temperature. The results of the stability test using a halogen lamp 34 W/m2 for 5 hours, that the substitution of chlorophyll with metal ions Zn2+ and Cu2+ has been shown to form more stable than natural chlorophyll. The characterization of the optical properties, the combination of ZnO / chlorophyll in the form of hybrid films has led to a shift in the absorption region of ZnO becomes more widely from the UV to Visible. ZnO/chlorophyll has absorption range of 350-515 nm, ZnO / Zn-feofitin 332-401 nm and 332-632 nm for Cu-feofitin. The combination of ZnO/chlorophyll and CuSCN as a solid electrolite in hybrid solar cell, a modified chlorophyll with metal ions Zn2+ and Cu2+ has been shown to form a more stable I-V curve. It is characterized by its fill factor value greater than natural chlorophyll. Nevertheless, solar cells with natural chlorophyll has been able to produce higher efficiency values of chlorophyll were substituted.
Keyword: Hydrothermal, ZnO/Chlorophyll modified, Hybrid Solar Cell