Sieving machine is used to sift material of sand and stone previously mixed. Sieve machine is a measuring instrument to determine the size of sand grains that can be used in building construction. The purpose of this research is to calibrate the sieving machine using profile projector with standard method ASTM E-11 2004. Based on this research, the conclusion of calibration data of sieving machine has been obtained. It was found that the sieving machine used in this research can be used to determine the size of sand grains used for construction. The uncertain value of the width opening sieve is 15.8 μm and the diameter of wire is 0.02 mm, so that the value of evaluation is lower than the allowed geometry deviation limit. Thus it can be concluded that the sieve machine is still within the permissible geometry tolerance limit.
Department of Mechanical Engineering, Faculty of Engineering, Universitas Riau, Indonesia
Balai Besar Bahan dan Barang Teknik Bandung, Indonesia
University rankings have become a trend to gauge the credibility and quality of the university. The university rating has generated much debate about the usefulness, method and accuracy of the assessment results. There are some institution who issued university rankings such as QS, 4ICU, CWUR and Webometrics. The universities were assessed depending on research indicators and opinion surveys. There are many anomalies in ranking gap values between universities as well some clumsiness of values at certain regions. The inadequacy of those tabulation indicators to assess most universities will look purely for reasons of obvious statistical instability. Statistically, there are three regions of ranking gap values: low, medium and high. Standard deviation of ranking gap values for universities in USA and UK is 6-7, Japan is 16, South Korea is 70, and Singapore, Malaysia and Indonesia are no applicable. Those values indicate inconsistency of judgment and invalid and inaccuracy data used in the assessment.
Ocean and Aerospace Research Institute, Indonesia
Mechanical Engineering, Universiti Teknologi Malaysia, Malaysia
One of the welding technology is SMAW (Shielded Metal Arc Welding) has its own advantages, such as, the current as the heat source used can be varied, easy to be used in various welding positions, penetration and the electrode width of welding can be adjusted. In order for proper welding speed, this research uses SMAW welding machine with sliding adaptive vertical system that varies the flow and welding speed to the welding characteristics, by doing visual observation and mechanical properties using tensile test. The welding speed is controlled using arduinouno with stepper motor rotation as the driving force. The material used is mild steel which has been tested for its composition content, the groove used is single V groove with 60 ° and electrode used is E6013 electrode. The number of specimens varied by 9 specimens with the highest tensile strength is 543,48 MPa and the lowest value is 253,75 MPa. Micro welding structure is determined by many factors including heat input, current strength, welding speed, and cooling rate. In this study the HAZ area has a larger grain structure than base metal and weld metal.
Laboratory of Production Technology, Department of Mechanical Engineering, Faculty of Engineering, Universitas Riau, Indonesia
Department of Mechanical Engineering, Faculty of Engineering, Universitas Riau, Indonesia
