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Medium density fiberboard (MDF) is an engineered wood product that has density and specific gravity similar to solid wood, ranging from 600 to 800 kg/m3 of density and 0.6 to 0.8 of specific gravity. This makes MDF suitable to partially replace solid wood, particularly for interior application. Approximately over than 100 million m3 of MDF are produced in 2020, resulting in a large amount of waste MDF will be generated in the next 20 years. MDF is produced using urea-formaldehyde (UF) resins adhesive. UF resins adhesive is a poly-condensation product of urea and formaldehyde via an alkaline acid two-step reaction. Sustainable MDF production is required as the world is facing climate change and deforestation. Recycling is a way to support sustainable production in the engineered wood products manufacturing. Many attempts have been done to find ways to recycle waste MDF. The main problem is UF resins, which bond the MDF panel fibers. In order to re-manufacture the waste MDF into new recycled MDF, UF resins should be eliminated from the waste MDF before being used. The presence of UF resins in MDF can interfere with the utilization of the recycled fibers, whether it will be used as a raw material for new MDF or other composite products. This paper reviews the process of removal of cured UF resins from waste MDF panel by considering the hydrolytic stability of cured UF resins for MDF recycling, providing a comprehensive review of how cured UF resins can be removed from waste MDF and characterization of recycled fibers obtained from recycling prior to re-manufacturing of recycled MDF panel.Keywords: hydrolysis, medium density fiberboard, resin, recycling, resin removal, urea-formaldehyde

Pine oleoresin is a valuable non-timber forest product commodity in Indonesia. A traditional tapping using small-sized hoes ("kadukul" in Sundanese or "pethel" in Javanese) are widely applied. Given the protection of occupational safety and health is a worker's right, various ergonomic issues were discussed in this study. Musculoskeletal disorders (MSDs) was examined by using Standardized Nordic Questionnaire and Wong-Baker Pain Rating Scale instruments, physical-mental-social fatigue was measured by Cumulative Fatigue Symptoms Index (CFSI), and job satisfaction was tested from eight variables such as wage, employment status, accessibility, health service, living facilities, work equipment, training, and social facility. This study revealed that most of the workers suffered from intense MSDs in the shoulder, arm, wrist, hand, thigh, calf, and foot (mostly right body side). This finding was in line with the CFSI analysis. The common fatigue symptoms suffered by the workers were in the category of the physical dimension, such as in sub-dimensions of general fatigue, chronics fatigue, and physical disorder. The job satisfaction analysis confirmed that two variables, i.e., wage and employment status, influenced job satisfaction significantly in a positive association. Proper personal protective equipment and workaid, working techniques improvement that meets occupational safety and health standard, and safety behavior incentive should be considered as effective strategies in improving the worker's safety and health protection.Keywords: forest harvesting, forestry worker, non-timber forest product, physical fatigue, safety

Lignin is the second most abundant biopolymer, exceeded only by cellulose, and comprises 15-25% of the dry weight of woody plants, with around 285,000 tons/year of production capacity globally. This study aims to utilize the lignin obtained from the waste of bioethanol production from oil palm empty fruit bunches (OPEFB) as a mortar additive. The use of mortar as a material for road construction is increasing, but its long time hardening is causing problems such as traffic jams. Lignin can be used as an additive to shorten the hardening time of mortar. Lignin was isolated at various NaOH concentrations and temperatures of OPEFB pretreatment for bioethanol production. The workability of the slump and compressive strength of mortars generated were further tested. Lignin from OPEFB can be used as a water reducer in the mortar with improved workability as much as 24.4% compared to controls. The addition of lignin could also increase the compressive strength at the mortar age of 7 and 28 days compared to the commercial lignosulfonate and control on the various water-cement ratios. The setting time of mortar with the lignin addition increased rapidly, reaching up to 80% at the 7 days, indicating that curing time is getting shorter. The most remarkable improvement of compressive strength with suitable workability and high-quality concrete was reached by 1% lignin addition and 0.45 water-cement ratio with compressive strength 38.81 N/mm2 at 28 days.Keywords: compressive strength, lignin, mortar, OPEFB, water reducer

The vast production of medium - density fiberboard (MDF) in the world is expected to generate a large quantity of waste MDF after its service life, which requires the recycling of waste MDF (wMDF). This work attempted to investigate the removal of cured urea-formaldehyde (UF) resins adhesive in wMDF using hydrolysis for a possible way of recycling wMDF. The wMDFs were fabricated with two kinds of recycled fibers (RFs): refiner recycled fibers (RRFs) and hammer mill recycled fibers (HRFs) from red and radiata pine. The wMDFs were also produced at different RFs contents, such as 0, 5, 10, 20, 30, 50, and 100%. The panels were then hydrolyzed with water and oxalic acid solution to remove the cured UF resins. The Kjeldahl method was applied to determine the nitrogen (N) content in the panel before and after hydrolysis. Regardless of the wood species and recycling process, the mass loss, pH, and formaldehyde liberation of wMDFs after hydrolysis were greater for oxalic acid than those in water , confirming a greater N content had been extracted by oxalic acid than water. The resin removal became greater as the RFs content increased. In addition, the resin removal was slightly greater in wMDFs made of HRFs than the RRFs. Moreover, red pine RFs gave higher resin removal than radiata pine. These results suggest ed that a proper combination of the recycling process and additives could make it possible to recycle wMDF panels in the future. Keywords: cured urea-formaldehyde, hydrolysis, medium-density fiberboard, oxalic acid, recycling

The increasing rates of forest degradation and deforestation has been decreasing carbonstocks of forest. Pekon kelungu is one of the village that developing the community forestusing agroforestry system that is also has a function as a carbon stock. The research wasconducted to determine the dominant vegetation and to predict the amount of above groundcarbon stock at the community forest in Pekon Kelungu. The Important Value Index (IVI) wascalculated to measure plants domination. Allometric equation was used to measure carbonstored for living and dead tree, volume formulas for necromass and Biomass ExpansionFactor formula for litter and seedlings. Durian, cacao and campaca is the dominat tree poleand seedling, respectively. The total carbon of above ground biomass of community forest inPekon Kelungu is amounted to 101,61 ton/ha. Carbon stored on tree component is amountedto 99,92 ton/ha, necromass is amounted to 0,81 ton/ha, litter is amounted to 0,87 ton/ha andseedling is amounted to 0,02 ton/ha.Keyword : carbon stock,community forest, IVI

University of Lampung has quite extensive green open space with the diversity of vegetation. The presence of green open space consider to have benefits to control the temperature and humidity. This research was aimed to know the influence of vegetation on the green open space to control temperature, humidity, the degree of comfort and aesthetics. This study used randomized group complete design model with purposive sampling techniques and interviews which conducted on February 2015. The results of this research showed that the highest air temperature in the morning, noon and evening were in the football field. The lowest temperature in the morning, noon and evening were in mixed forest stands. The highest humidity in the morning was in Ficus benjamina stands, while in the afternoon and evening were in Enterolobium cyclocarpum stands. The lowest air humidity in the morning, noon and late afternoon were in thefootball field. Based on the temperature and humidity index (THI) the football field, Enterolobium cyclocarpum stands, Ficus benjamina stands and mixed forest stands were included in the uncomfortable category. Based on perception of repondens towards the comfort level and green open space aesthetic, the football field categoried as uncomfortable and less aesthetic. While, Enterolobium cyclocarpum stands, Ficus benjamina stands and mixed forest stands categoried as comfortable and aesthetic. Keywords: comfort, micro-climate, open green space

Transaksi bisnis jual beli e-Commerce saat ini memasuki mulai bergeser memanfaatkan perangkat gadget/smartphone. Perkembangan inilah yang disebut dengan m-Commerce, yakni memanfaatkan smartphone untuk melakukan transaksi jual beli barang. Zona Komputer Banjarnegara telah memiliki website e-Commerce. Namun demikian, Zona Komputer berinovasi untuk menjadi yang terdepan dalam melayani konsumen yakni dengan membuat m-Commerce untuk memudahkan pelanggan dalam transaksi jual beli. Metode pengembangan sistem yang digunakan dalam penelitian ini yaitu menggunakan metode waterfall. Dari hasil penelitian ini akan dihasilkan sebuah aplikasi mobile untuk melakukan transaksi jual beli pada toko komputer Zona Komputer Banjarnegara.Kata Kunci: e-Commerce, m-Commerce, android