The development of diesel engines faces challenging targets to satisfy stringent emissions regulation. To address this issue, the use of alcohol biofuels such as methanol and ethanol has attracted ...numerous attention due to their physicochemical properties and the possibility to be produced from renewable sources and agricultural waste material. Compared to ethanol, longer carbon alcohol such as butanol has higher energy density and lower latent heat, hygroscopicity, aggressivity, and toxicity. It can also be produced from biomass. Yet, despite its noticeable advantages, the use of butanol in the internal combustion engine is hindered by its low production efficiency. If Acetone-Butanol-Ethanol (ABE) is further distilled and purified, pure butanol and ethanol can be acquired, but this involves an energy-intensive process, thus increasing the production cost of butanol. To solve this problem, the direct use of ABE as a biofuel is considered a promising strategy. The idea of using ABE directly in internal combustion engines is then proposed to solve the economic issue of high butanol production costs. A scoping literature review was performed to screen and filter previously published papers on ABE by identifying knowledge gaps instead of discussing what is already known. Therefore, repeated and almost identical studies were eliminated, thus reporting only the most significant and impactful published papers. In terms of the objective, this article aims to review the progress of ABE as a promising biofuel in regard to the engine performance, combustion, and emission characteristics. Focus is also given to ABE’s physicochemical properties. Despite their considerable importance, the fuel properties of ABE are rarely discussed. Therefore, this review article intends to analytically discuss the physicochemical properties of ABE in terms of their calorific value, density, kinematic viscosity, and distillation. In general, it is concluded that engine emissions such as NOx and Particulate Matter (PM) could be reduced considerably with the use of ABE. Yet, the BSFC was found to increase due to the relatively lower calorific value and density of ABE blends as opposed to gasoline or diesel fuel, thereby increasing its fuel consumption. In terms of ABE’s fuel properties, in general, ABE can be used due to its satisfying physicochemical properties. However, it should be noted that the ABE-gasoline/diesel blends are greatly influenced by each of its component ratios (acetone, butanol, ethanol).
Cetane number (CN) is one of the important fuel properties of diesel fuels. It is a measurement of the ignition quality of diesel fuel. Numerous studies have been published to predict the CN of ...biodiesels. More recently, the utilization of soft computing methods such as artificial neural networks (ANN) has received considerable attention as a prediction tool. However, most studies in the use of ANN for estimating the CN of biodiesels have only used one algorithm to train a small number of datasets. This study aims to predict the CN of 63 biodiesels based on the fatty acid methyl esters (FAME) composition by developing an ANN model that was trained with 10 different algorithms. To the best of our knowledge, this is the first study to predict the CN of biodiesels using numerous ANN training algorithms utilizing sizeable datasets. Results revealed that the ANN model trained with Levenberg-Marquardt gave the highest prediction accuracy. LM algorithm successfully predicted the CN of biodiesels with the highest correlation and determination coefficient (R = 0.9615, R2 = 0.9245) as well as the lowest errors (MAD = 2.0804, RMSE = 3.1541, and MAPE = 4.2971). Hence, the Cascade neural network trained with the LM algorithm could be considered a promising alternative to the empirical correlations for predicting biodiesel’s CN.
Nowadays, information systems is an important point in supporting business strategies including in education division. Critical assets related to information systems are very susceptible to threats ...that can exploit and damage assets until they lead to disruption of business processes and even lead to financial losses. PT. Autocomp Systems Indonesia (PASI) has implemented Information Security Management System (ISMS) based on ISO / IEC 27001 to define a set of risk management strategies. However, some threats still occur and make the organization to get losses. The organization needs to conduct an evaluation of risk management that has been implemented to determine whether the risk protection strategy is adequate. Evaluation is done by comparing the current condition with the expected ideal condition using Catalogue of Practices from OCTAVE. The gaps found and then the risk assessment of the related assets is carried out. The results of this study indicate that the level of risk management maturity obtained by the organization is 89.40 %. The biggest gap is found in the contingency plan/disaster recovery plan and vulnerability management. Then a mitigation plan is proposed from the results of the risk assessment using the OCTAVE Allegro approach so the risk can be controlled properly.
