Indonesian Journal of Engineering and Science https://www.aps.or.id/journal/index.php/ijes <p><strong>Indonesian Journal of Engineering and Science (IJES : ISSN 2774-373X)</strong> is a peer-reviewed journal that aims at the publication and dissemination of original research articles on the latest developments in all fields of engineering science and technology. The journal publishes original papers in English, which contribute to the understanding of engineering science and improvement of the engineering technology and education. Papers may be theoretical, experimental and paper review. The contribution should be unpublished before and not under consideration for publication elsewhere.</p> en-US aspensriwijaya@gmail.com (Gunawan) amir@unsri.ac.id (Amir Arifin) Wed, 08 Sep 2021 03:57:32 +0000 OJS 3.2.1.2 http://blogs.law.harvard.edu/tech/rss 60 WORK SCHEDULING PROGRAM DESIGN FOR LECTURE ATTENDANCE CONTROL AND LECTURER WORKLOAD CALCULATION WITH FINGERPRINT AND RFID IDENTIFICATION DEVICE https://www.aps.or.id/journal/index.php/ijes/article/view/24 <p>The essential factor in achieving a good learning process is discipline in the lecture process. Students and lecturers are encouraged to be disciplined and active participants in the lecture process, allowing the Lecturer's principal duty of transforming and disseminating science and technology to become more concentrated. Furthermore, to eliminate overlapping lecture schedules, lecture hours, and lecture venues that do not meet needs, it is easier for stakeholders to monitor and regulate lecturers' and students' lecture attendance so that quick and accurate decision-making can be done. To establish discipline in school utilizing biometric identification technology (fingerprints) and Radio Frequency Identification (RFID) technology, developing application software to make it easier to manage work schedules is required. The Work Scheduling program is an online application built with the PHP programming language, MySQL database, and fingerprint and RFID identification support devices that are expected to be effective and efficient tools in the process of scheduling lectures and recording lecture attendance of students and lecturers, making it easier to publish lecture schedules.&nbsp;</p> M.A. Ade Saputra, Amrifan Saladin Mohruni, Irsyadi Yani Copyright (c) 2021 M.A. Ade Saputra, Amrifan Saladin Mohruni https://creativecommons.org/licenses/by-sa/4.0 https://www.aps.or.id/journal/index.php/ijes/article/view/24 Wed, 08 Sep 2021 00:00:00 +0000 HYDRODYNAMIC ANALYSIS OF BIONIC CHIMERICAL WING PLANFORMS INSPIRED BY MANTA RAY EIDONOMY https://www.aps.or.id/journal/index.php/ijes/article/view/25 <p>In this paper, inspired by the external morphology of a manta ray (<em>Mobula alfredi</em>), four chimerical wing planforms are designed to assess its gliding performance. The planforms possess an arbitrary combination of extra hydrodynamic features like tubercles at the leading edge (L.E.) and trailing edge (T.E.) inspired by humpback whale's flippers and flukes, respectively, as longitudinal ridges inspired by whale shark's economy. In addition, another planform is designed to investigate the possible effects of manta ray's injuries (geometric deficiency) generated by predator's attacks or boat strikes on its locomotion (gliding) performance. In this regard, turbulent flow physics involved in the problem is numerically simulated at different angles of attack (AoA). High Reynolds number, 10<sup>6</sup>, corresponding to the swimming of a juvenile manta ray at an average speed equals one m/s. The results show that the manta ray-inspired planform with L.E. undulations exhibits a superior performance at high AoAs than its other counterpart variants. In addition, the results demonstrate that injuries on the manta ray's body can noticeably modify hydrodynamics and, as a result corresponding hydrodynamical forces and moments acting on the swimming animal in the gliding phase.</p> Arash Taheri Copyright (c) 2021 Arash Taheri https://creativecommons.org/licenses/by-sa/4.0 https://www.aps.or.id/journal/index.php/ijes/article/view/25 Wed, 08 Sep 2021 00:00:00 +0000 INTERGRANULAR CORROSION AND DUCTILE-BRITTLE TRANSITION BEHAVIOUR IN MARTENSITIC STAINLESS STEEL https://www.aps.or.id/journal/index.php/ijes/article/view/23 <p>Material mechanical behavior is critical for both safety and economic considerations. Because engineering items are manufactured using appropriate grade materials, mechanical approval of the materials used must be completed before assembly. Petrochemicals, marine, and biomaterials are just a few of the industries that use stainless steel. Despite its extensive use, structural failure is still frequently caused by inadequate stainless steel type selection. As a result, dangerous conditions, resulting in personal harm or financial loss. Dangerous conditions is might result in accidents, resulting in personal injury or financial loss. Martensite stainless steel is a type of stainless steel with a high strength value but is brittle, necessitating careful handling. Intergranular corrosion, sensitization, tempering heat treatment, and the Ductile to Brittle Transition Temperature (DBTT) are topics still working on Martensite stainless steel for researchers.</p> Gunawan Gunawan, Amir Arifin Copyright (c) 2021 Gunawan Gunawan, Amir Arifin https://creativecommons.org/licenses/by-sa/4.0 https://www.aps.or.id/journal/index.php/ijes/article/view/23 Wed, 08 Sep 2021 00:00:00 +0000 WELDING ANALYSIS OF GRAY CAST IRON ASTM A48 CLASS 40 USING SMAW https://www.aps.or.id/journal/index.php/ijes/article/view/26 <p>The mechanical and physical characteristics of gray cast iron are intricately bound to its application as an essential material in manufacturing various goods. SMAW (Shielded Metal Arc Welding) is the most simple and widely used electric arc welding method. In this work, ASTM A48 gray cast iron Class 40 was joining using the SMAW method with the welding position used was 1G or underhand position. The joining used is the Butt Joint using an open Singel V seam with a current of 120A. The joining of Welding was characterized through dye penetrant and hardness tests. Rockwell hardness tests on base metal and heat affected zone reveal that the heat affected zone has the highest hardness value of 56.5 HRC, while the base metal has the lowest hardness value (41 HRC). Graphite, pearlite, and pearlite were all visible in the microstructure study.</p> Diah Kusuma Pratiwi, Amir Arifin, Reza Andre Suhada Copyright (c) 2021 Dr. Diah Kusuma Pratiwi, Amir Arifin, Reza Andre Suhada https://creativecommons.org/licenses/by-sa/4.0 https://www.aps.or.id/journal/index.php/ijes/article/view/26 Wed, 08 Sep 2021 00:00:00 +0000 INVESTIGATION PERFORMANCE OF PICO HYDRO WATER PIPE TURBINE https://www.aps.or.id/journal/index.php/ijes/article/view/27 <p>The flow of water in the pipeline for household needs is a source of energy that can generate electrical energy through Pico hydro turbines or small-power water turbines. The experiment has been conducted on a 10 Watt Pico hydro turbine mounted on a water pipe against changes in water flow discharge. The turbine performance analysis is conducted experimentally (actual) and theoretically (ideal). The analysis results showed the greater the discharge flow, the greater the power generated by the turbine. In tests with a maximum discharge of 8.9 l/min, the actual power of 1.121 Watts, the torque of 0.005 Nm with a rotation speed of 2146.8 rpm and efficiency of 12.59%; while the ideal power is based on Euler turbine equation of 4.2 Watts and torque of 0.016 Nm. So, the maximum turbine power that can be generated is only 26.67% ideal. Efficiency turbine decreases with increased discharge; in this test, the maximum efficiency was 24.89% at 5.8 L/min flow discharge.</p> Marwani Marwani, Muhammad Zahri Kadir, Ronny Egetha Putra Copyright (c) 2021 Marwani Marwani, Muhammad Zahri Kadir, Ronny Egetha Putra https://creativecommons.org/licenses/by-sa/4.0 https://www.aps.or.id/journal/index.php/ijes/article/view/27 Wed, 08 Sep 2021 00:00:00 +0000