Judul: Penilaia Level Resiko Gangguan Kesehatan Kegiatan Delimbing Pohon Jati Masak Tebang dengan pendekatan Analisis Biomekanik
Abstrak: Delimbing atau pembersihan cabang dalam istilah pemanenan Indonesia merupakan salah satu kegiatan pemanfaatan hasil hutan kayu (HHK) yang mencakup berbagai kegiatan siklus secara urut dan acak. Kegiatan delimbing berisiko pada gangguan keselamatan dan kesehatan kerja (K3) dan dapat menimbulkan musculoskeletal disorders (MSDs). Penelitian ini bertujuan mengidentifikasi level risiko MSDs pada delimbing kayu jati melalui pendekatan analisis postur. Postur tubuh pekerja dianalisis dengan analisis biomekanik menggunakan software 3 Dimension Static Strength Prediction Progam (3DSSPP), kemudian dilanjutkan dengan analisis Range of Motion (ROM). Analisis biomekanik menyajikan hasil compression force dan shear force pada lumbar ke-5 sacrum ke-1 (L5/S1). Postur kerja yang memiliki compression force >3400 N yaitu postur berdiri membungkuk dan berdiri sangat membungkuk pada elemen kerja delimbing. Hasil Recommended Weight Limit (RWL) diperoleh sebesar 3,94 kg dan Lifting Index (LI) sebesar 2,79 tergolong sebagai pekerjaan berisiko sedang.
Keyword: biomechanics, delimbing, MSDs, ROM, RWL/LI

Judul: Work Posture Analysis of Delimbing Activities on Ripe Teak Tree with REBA, RULA, and OWAS Methods
Abstrak: Operasi pemanenan kayu di Indonesia sering kali menggunakan sistem motor-manual. Postur pekerja saat melakukan kegiatan dengan sistem ini memiliki tingkat risiko musculoskeletal disorders (MSDs) yang tinggi. Kegiatan delimbing atau pemotongan cabang, yang merupakan salah satu bagian dari kegiatan pemanenan hutan, tidak selalu dilakukan secara berurutan dari bagian pangkal menuju ujung (searah arah rebah). Terkadang, delimbing dilakukan secara berlawanan atau acak yaitu dari ujung menuju pangkal (berlawanan dengan arah rebah kayu) sehingga sering kali menghasilkan postur tubuh yang janggal. Penelitian mengenai analisis postur dalam kegiatan delimbing pohon jati masak tebang dengan urutan maupun secara acak perlu dilakukan sehingga dapat menganalisis risiko MSDs akibat postur kerjanya. Penilaian risiko MSDs dilakukan dengan beberapa analisis yaitu Range of Motion, Rapid Entire Body Assessment, Rapid Upper Limb Assessment, dan Ovako Work Posture Analysis System. Hasil analisis menunjukkan bahwa metode delimbing yang lebih berisiko untuk menyebabkan MSDs merupakan metode acak. Faktor yang menyebabkan risiko cedera pada kegiatan delimbing merupakan postur tubuh yang janggal (secara statis maupun berulang-ulang), beban chainsaw, serta permukaan area pemotongan cabang yang tidak stabil., Wood harvesting operations in Indonesia often use a motor-manual system. The posture of workers when carrying out activities with this system has a high risk of musculoskeletal disorders (MSDs). Delimbing or branch cutting, which is a part of forest harvesting activities, are not always carried out sequentially from the base to the tip (in the direction of falling). Sometimes, delimbing is done in opposite or random ways, namely from the tip to the base (against the direction of felling of the wood), which often results in awkward body postures. Research on posture analysis of delimbing activities in ripening teak trees in sequence or random method needs to be carried out so that it can analyze the risk of MSDs due to their work posture. MSDs risk assessment is carried out with several analyzes, namely Range of Motion, Rapid Entire Body Assessment, Rapid Upper Limb Assessment, and Ovako Work Posture Analysis System. The results shows that the delimbing method that has more risk of causing MSDs is the random method. Factors that cause the risk of injury in delimbing activities are awkward body postures (statically or repeatedly), chainsaw’s weight, and the unstable surface of the branch cutting area.
Keyword: delimbing, MSDs, risk, work order, work posture

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