Journal of Engineering and Scientific Research

Numerical Simulation of The Magnetic Levitation System in State-Space Form

Opa Mustopa, Sovian Aritonang — Sat, 31 Dec 2022 00:00:00 +0000

The maglev system is a technology that uses the repulsive force between magnets to float or levitate an object or vehicle. Maglev trains use electromagnets to counter the gravitational force of an object, so that the object can float in the air. With this technology, the resulting loss between the workpiece and the base can be eliminated. The technology used in this train is Electromagnetic Suspension (EMS). The research began by modeling the maglev system in the form of state space. Furthermore, the stability system model that has been built is analyzed. Finally, it is analyzed how the numerical simulation of an open loop without control is analyzed. The result of this research is that the floating system (maglev) is an unstable system if it is run in an open loop, so the maglev system requires sensors and controls in its operation.

Strength Analysis of Tubular Oil to Oil Cable Box Power Transformer GIS 60 MVA in the Case of Voltage Arc Energy Using the Finite Element Analysis Method

Asep Dharmanto, Asep Saepudin, Wilarso Wilarso — Sat, 31 Dec 2022 00:00:00 +0000

The power transformer is an essential part of the electrical distribution system because it must be reliable and safe from fire and explosions, one of which is brought on by internal oil arching that results in overheating. In general, on the high voltage side of the transformer, there are power transformers fitted with tubular oil to oil cable boxes for the demands of the client. The tubular oil to oil cable box is installed to reduce space in substations with limited space as well as to boost safety against weather and pollution at the high voltage terminal section of power transformers. The goal of this investigation is to determine the cause of an explosion that occurred in a tubular oil-to-oil cable box on the high voltage side of a Gas Insulation System (GIS) type power transformer with a power of 60 MVA and a voltage rating of 150/20 kV. For all parties involved, this incident will serve as a lesson about what to avoid doing in the future with similar power transformers. In this study, we will use a qualitative method with Finite Element Analysis (FEA), which takes samples and data of a Gas Insulation System (GIS) power transformer on the high voltage side, especially in the analysis of tubular strength. This power transformer has a voltage rating of 150/20 kV and a power of 60 MVA. Applying normal pressure to a pressure that could harm the tubular oil to oil cable box can prevent damage. The tubular oil to oil cable box is built of SS400 material and has an 8mm thickness so that it can be determined how robust it is.

Usability of Lampung Heritage Virtual Reality Tour

Sat, 31 Dec 2022 00:00:00 +0000

Lampung Heritage Virtual Reality Tour was developed as a tool to educate the importance of Lampung’s historical heritage. It represents eight Lampung historical heritage sites in the virtual reality world, namely the Lampung Museum, Thay Hin Bio Vihara, Al-Anwar Mosque, Lampung Siger Tower, Krakatau Monument, Kerti Bhuana Temple, Nuwo Sesat Traditional House, and the Japanese Caves. Functional features of the Lampung Heritage Virtual Reality Tour are visiting virtual tourist spots and viewing information on virtual tourist attractions. Digital tourists can select a virtual tourist spot with the location panel. The user perception and satisfaction require a qualitative measurement to understand its impact on educating Lampung's historical heritage. Using usability, we should understand the quality of the Lampung Heritage Virtual Reality Tour. The tools to measure the usability level of the application are the User Acceptance Test and the System Usability Scale. There were 15 questions User Acceptance Test (UAT) with a composition of five questions affordance, four questions signifier, and six questions feedback. According to the SUS standard, we asked ten questions on the System Usability Scale (SUS). The result for UAT was an average of 95.75%, which consist of 95.00% affordance, 94.79% signifier, and 97.45% feedback. The result of SUS was Good, based on a score of 83.39. The Lampung Heritage Virtual Reality Tour meets good usability standards, making the application suitable.

Performance analysis of Newton-Raphson Power flow computations based on Power and Current Mismatches

Lukmanul Hakim, Khairudin Khairudin, Zulmiftah Huda — Sat, 31 Dec 2022 00:00:00 +0000

This work studies the performance of single-phase power flow computations implemented using vector-based Python scripting language. Two approaches are considered, namely the current mismatch and power mismatch based on Newton-Raphson method. Both approaches are developed using rectangular coordinates and tested through a variety of IEEE test systems modelling high voltage transmission networks. The computational burden and accuracy of both implementations are duly discussed. This work will be later incorporated into our vector-based Non-linear Primal-Dual Interior Point Method as constraints.

Design and Development of Management Information Systems at the University of Lampung Library Repository Using the Laravel Framework.

Sat, 31 Dec 2022 00:00:00 +0000

The University of Lampung has a library that is used to support the university's academic activities. One of the services at the Unila library is a digital library service that is used to upload scientific works into the repository, but there are still manual processes that are carried out repeatedly such as collecting requirements files, giving accounts and coordinating with students who require to come to the library continuously. so that the process carried out is not efficient. This study aims to build a management information system on the repository using the Laravel framework which can be used as a solution for the Unila library to make it easier for users to upload scientific works into the digital library repository. The development of this application uses the kanban method, which includes the process of analyzing system requirements, designing, developing to testing. The results of this study succeeded in providing a file upload service for account application requirements and uploading a repository link that was validated by the admin. The service is then tested using the blackbox method which produces the expected output so that it can be concluded that the application passes the test.

A Geoelectrical Study of Aquifers in the Natar Region, South Lampung

Sat, 31 Dec 2022 00:00:00 +0000

The conditions for the development of population growth and development in the area around the City of Bandar Lampung are very fast and starting to get crowded, as happened in the District of Natar South Lampung, especially in the Village of Pemanggilan. This condition causes an increase in the need for clean water resources in line with the increase in groundwater exploitation. Therefore it is necessary to map the potential of groundwater through aquifer mapping and aquifer rock layers through geoelectrical measurements. This study aims to determine the potential of groundwater from volcanic aquifer systems based on geoelectrical measurements. The method used in this study is geoelectric resistivity using the Wenner-Schlumberger configuration with 3 measurement points. The results of the study show that using the geoelectrical resistivity method, layers with a resistivity value of ? 30.3 ?m are interpreted as shallow aquifers at depths varying from 1 to more than 24 meters with lithology suspected to be tuff and tuff sandstones, which according to geological data are included in the Lampung Formation. Using the 2D geoelectric method, the distribution of shallow aquifers in the study area to a depth of 24 meters can also be determined. The data obtained is expected to be used as supporting data for the sustainable use of water sources.

Domestic Wastewater Disinfection Planning for Constructed Wetland Treatment Effluent

Sat, 31 Dec 2022 00:00:00 +0000

Excessive water consumption to meet water needs has changed aquatic water quality and quantity. Focus on domestic wastewater treatment via built wetlands. Disinfection protects humans against disease-causing viruses, bacteria, and protozoan parasites in wastewater. This study planned the disinfection of artificial wetland wastewater to fulfill microbiological criteria. From the examined data, each unit's design criteria and disinfection effectiveness for the created wetland outlet in the WWTP unit will be discussed. The created wetland must process 8696 cfu/100mL of fecal coliform. Despite good processing efficiency, 94% of fecal coliforms do not fulfill quality criteria. WWTP's wetland emits 8.011 mg/L of Ammonia. 90% chlorine costs Rp. 35,000/kg on the market. Total disinfection costs are rough Rp. 1,018,210.73. Water quality, lamp output power, and exposure distance affect lamp intensity. The lamp's electric power controls the beam's intensity; the more power, the more emission. The emitted power isn't equal to the lamp's electric power. According to the state electricity provider, families with a 900VA power limit will pay Rp. 1,352/kWh in July-September 2021. Nine 30-W bulbs irradiate bacteria. The lights will run for 24 hours non-stop. Hence the monthly electricity usage is 194.4 kWh or Rp 262.829.00.

Web-Based Interactive Virtual Tour as an Information Media and Introduction to Post-Pandemic Lecture Buildings at Universitas Lampung

Panji Kurniawan, Nugroho Ifadianto, Agung Cahyo Nugroho — Sat, 31 Dec 2022 00:00:00 +0000

This study aims to determine the effectiveness of architectural communication methods using a link embedded in online media or social media. This research method is an interactive communication simulation in the form of a Virtual Tour using the 360o panoramic image method. A 360o panoramic image is multiple images combined to get a wider, more detailed image. Panorama images will be set using software and then uploaded to a website's database. The public, in this case more concerned with the academic community, can easily get information about the shape of buildings and spaces from various predetermined points, without installing certain 3D Architecture software. It is enough to use a computer or smartphone based on iOS or Android and without using object tracking or the like to activate communication, because it is web-based, it can be easily accessed anywhere and anytime as long as the user has the intended link. This is an alternative media in providing information about the object, which in this case is the Lecture Building to the public, especially students and parents during the post-pandemic period.