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Indonesia has the largest peatland area in the tropical region, situated mainly in Sumatra, Kalimantan and Papua. Peat is an organic substance which is highly combustible in dry conditions; dried peat can burn easily and spread vertically and laterally along peat layers. In Indonesia, peat fires have often occurred in recent decades. Besides being influenced by the amount of organic content, smoldering peat fires are also effected by the drying rate, pyrolysis, and heterogeneous oxidation on the peat surfaces. In contrast to flaming combustion, which have been widely studied, smoldering peat fires remain little understood. To date, the major peat fire-related publications concern the pyrolysis and combustion stages. The contribution of the drying kinetics of peat in the peat fire phenomenon is important, as this could provide complete understanding of the peat fire process. The objective of this paper is to make an isothermal drying kinetics analysis of peat. Peat samples were taken from various locations in Indonesia with the largest peat distribution, namely South Sumatra, Central Kalimantan and Papua. An isothermal test was conducted using a Shimadzu MOC63u Moisture Balance. At certain interval times, the weight of the specimen was measured, until it reached a constant weight of less than a 0.05% change in moisture content. Isothermal analysis was conducted for each peat sample at temperatures of 60, 70, 80, 90, 100, and 110 o C. The results show that the activation energies from the isothermal measurement test were 24.97, 25.08, and 30.11 kJ/mole for Papuan, South Sumatran and Central Kalimantan peat, respectively.

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Crashworthiness is the ability to protect its occupant by absorbing the energy of impact during a collision. A crush initiator is one way to increase crashworthiness criteria at collision. The most widely applied crush initiator applications are holes, wall thickness reduction, grooves, notch, bead and corrugated. This study discussed making a functional model from the crashworthiness criteria which is known by CFE and SEA. Variable used variations of the crush initiator in the form of circular holes with different rotation angles and diameters. The rotation angle referred to in this study was 2 holes which are rotated based on the midpoint of the hole distance to the radial axis of the hole. The crush initiator was placed in a square column at each side with steel material. Besides, the wall thickness variable was added which can increase the energy absorption during a collision. The method used numerical simulation and experimental dynamic loading. The numerical simulation used the explicit finite element method by using ESI PAM-Crash. Both methods used the drop test model by using impact transferability. Impact transferability was rigid which was used to transfer impact loading during impact conditions. Experimental was used to validate the function model which was obtained through the least square method with sampling from numerical simulations. The results showed the same patterns produced by the functional and experimental models using the Taguchi method (L9) with 3 runs. The maximum of this pattern is 23% for CFE and 17% for SEA. Meanwhile, the average error of the S/N ratio shows 8.77% for CFE and 2.16% for SEA. This model function could be used by a crashworthy designer to estimate the value of CFE and SEA.