Sebelas Maret University

About: Sebelas Maret University is a education organization based out in Surakarta, Indonesia. It is known for research contribution in the topics: Population & Public health. The organization has 10901 authors who have published 10832 publications receiving 33057 citations. The organization is also known as: Universitas Negeri Surakarta & Universitas Sebelas Maret.

Constitutive models of magnetorheological fluids having temperature-dependent prediction parameter

Abstract: This work presents constitutive models of magnetorheological (MR) fluids, which can predict the shear and dynamic yield stress depending on temperature. Two existing models, the Herschel–Bulkley rheological and power law model, which are frequently used in MR fluid research, are adopted and modified to take the temperature into account. A new constitutive model of MR fluids is developed using the extreme learning machine (ELM) method. In this development, among many machine learning approaches, a simple and efficient learning algorithm for a single hidden layer feed-forward neural network (SLFN) is adopted and applied to the rheological model of MR fluids. The temperature, shear rate, and magnetic field are treated as inputs, and the shear stress is taken as an output. After formulating the models associated with experimental coefficients, the two most important properties of MR fluids; the shear and yield stress are predicted and compared with the measured values. The prediction accuracy for the field-dependent rheological properties of MR fluids in several different temperatures is evaluated and compared. It is shown that the ELM model developed in this work provides the best accuracy, followed by two other modified constitutive equations.

Minimizing waste using lean manufacturing and ECRS principle in Indonesian furniture industry

Abstract: The manufacturing industry is considered as one important sector, which has a significant influence on the economic growth of a country. The increase of fierce competition among products requires t...

Environmental risk of maritime territory subjected to accidental phenomena: Correlation of oil spill and ship grounding in the Exxon Valdez's case

Abstract: Ship has become inseparable part of international trading scheme which involves large scale commodities in export-import. During its operation to reach the designated destination, vessel traffic and geographical condition are possibly causing the accidents on the ship. As chain of reaction, commodities/cargoes can be spilled which influence surroundings. Emergency situation is certainly taking place if the cargo is classified as dangerous item, such as chemical compound and crude/product oil. Effect to environment can be immense, which includes living ecosystems and species. This work presents a series of discussions related to environmental casualties due to accidents which take place in maritime territory. Statistical data of accidental phenomena in the recent century is summarized. Infamous accident of the Exxon Valdez is considered as the prime case, and the environmental casualties are discussed which can be further references for maritime countries in regulation planning for prevention and mitigation accounting for oil spill.