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This research focuses on determining the level of inventory in a downstream supply chain for fuel products in Indonesian oil and gas company prespective. The variability in supply and demand is a problem in maintaining the stability of services to the consumers. High inventory costs that are completely borne by the company are also a problem that needs to be controlled. Therefore, determining inventory levels is very important to mitigate the variability of supply and demand that occurs with optimum inventory costs. This research designs a probabilistic model by considering variability in supply and demand to determine safety stock so that the correct level of Fuel Product inventory at each Storage Point can be determined. This research method is quantitative research based on empirical data. It is hoped that the research results will be able to obtain inventory control which can be taken into consideration by oil and gas company in managing the downstream supply chain of fuel products. [ABSTRACT FROM AUTHOR]

Filament winding is a widely used method for producing tubes and pressure vessels from composite materials. However, overlapping of fibers during the winding process can lead to rough surface and increased voids in the finished product. To improve the quality of CFRP materials produced through filament winding, the structure is cured either at room temperature or in an oven with a controlled heat profile, depending on the type of resin used. Various finishing techniques, including shrink tape, compression molding, and vacuum compression molding, have been attempted to improve the quality of the specimen. Among these techniques, vacuum compression molding has been found to deliver the best results in terms of surface roughness, with average roughness (Ra) values of 0.35 μm in the fiber direction and 0.61 μm in the transverse direction. This level of roughness is comparable to that achieved through milling machine manufacturing. Moreover, this technique ensures uniformity in fiber composition and volume fraction, achieving a homogeneous density of 1364.49 kg/m³ and the highest fiber volume fraction of 63 %. As a result, remarkable mechanical attributes, such as a tensile strength of 926.07 MPa and a stiffness of 21.35 GPa, can be obtained. In addition, by utilizing various finishing techniques, the tensile strength of these properties can be increased by up to 80 %. CFRP is a versatile material with unique characteristics, and selecting appropriate finishing techniques such as vacuum compression molding can significantly enhance its overall quality and mechanical properties. However, one drawback of the filament winding method is the poor outer surface finish which can be improved by vacuum compression molding. [ABSTRACT FROM AUTHOR]

The fabrication of a natural prepreg with poly-lactic acid (PLA) matrix and ramie fiber reinforcement was engineered on a laboratory scale by impregnating the unidirectional and bidirectional ramie fiber with PLA matrix solvent on a glass die. The obtained composite prepreg has been stored at a very low temperature to maximize its shelf life. Tensile and biodegradability tests of the composite laminates prepared by the hot-pressing method have also been conducted. Tensile test results show that the freezer-stored bidirectional 0/90° prepreg laminate specimen has the highest tensile strength of 71.44 MPa with a modulus of 2.70 GPa on average. Meanwhile, the unstored bidirectional 0/90° prepreg laminate specimen has the highest level of elasticity, with a modulus of 1.29 GPa on average. The biodegradability test shows the decomposition process of the composite laminate under actual composting conditions. Microscopic observation of the damaged specimen results shows good adhesion between the PLA matrix and ramie fiber and the decomposition of the biodegradability test samples. [ABSTRACT FROM AUTHOR]