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All Journal Jurnal Teknik Industri TEKMAPRO Journal of Industrial Engineering and Management Journal of Research and Technology Matrik : Jurnal Manajemen dan Teknik Industri Produksi Nusantara Science and Technology Proceedings International Journal of Eco-Innovation in Science and Engineering (IJEISE) Juminten : Jurnal Manajemen Industri dan Teknologi International Journal on Advanced Technology, Engineering, and Information System (IJATEIS)
Yustina Ngatilah
Universitas Pembangunan Nasional Veteran Jawa Timur
Agriculture, Biological Sciences & Forestry Automotive Engineering Biochemistry, Genetics & Molecular Biology Chemical Engineering, Chemistry & Bioengineering Civil Engineering, Building, Construction & Architecture Computer Science & IT Control & Systems Engineering Decision Sciences, Operations Research & Management Economics, Econometrics & Finance Electrical & Electronics Engineering Engineering Environmental Science Industrial & Manufacturing Engineering Law, Crime, Criminology & Criminal Justice Materials Science & Nanotechnology Mechanical Engineering Medicine & Pharmacology

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Journal : Nusantara Science and Technology Proceedings

 1 
Study of Making Potassium Posphate from Seaweed Industrial Wastewater Pujiastuti, Caecilia; Sumada, Ketut; Ngatilah, Yustina; Widya P, Vika; Arief S, Purwanto
Nusantara Science and Technology Proceedings 1st International Conference Eco-Innovation in Science, Engineering, and Technology
Publisher : Future Science

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.11594/nstp.2020.0526

Abstract

Seaweed industrial wastewater which contains 17.9% potassium can be used as a raw material for making multi-nutrient fertilizers. 1 liter of wastewater is reacted with 1 N phosphoric acid with a certain volume (15, 20, 25, 30, 35 ml) and 30 ml of aluminum sulfate (17,18,19,20,21%) stirred at a speed of 35 rpm for 25 minutes. The precipitate formed is dried. The results showed that the greater the volume of acid and the concentration of aluminum sulfate added with fertilizer obtained and the K, P, and S ion content was getting smaller. Fertilizer produced with the highest content of K ions (9.3%), P ions (9.7%), and S (9.295%) was obtained in the addition of 17% Aluminum Sulfate coagulant and 15 ml volume of H3PO4 (1N), and fertilizers produced weighing 4.0128 grams.
Optimization of Annual and Five Years Tax Payment Services for Motorized Vehicles in Samsat "X" Ngatilah , Yustina; Siati; Pujiastuti , Caecilia
Nusantara Science and Technology Proceedings 1st International Conference Eco-Innovation in Science, Engineering, and Technology
Publisher : Future Science

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.11594/nstp.2020.0529

Abstract

The Samsat "X" office is a joint service office between the police, the regional income office, and the Jasa Raharja. The services provided are annual and five years of tax payments for motorized vehicles. The current service process is having an uncertain or probabilistic service time and long waiting time, resulting in long queues. This long queue condition causes taxpayer dissatisfaction. One of the methods to solve this problem is the Monte Carlo simulation. Monte Carlo simulation is a simulation method for solving problems with a set of sampling techniques from a probabilistic process. The objective of this research is to determine the optimum number of service personnel by using the Monte Carlo simulation method. The results of this simulation are the optimum conditions (best) for the tax payment services problem at the Samsat "X" office. The result shows that the optimum conditions are obtained with an average waiting time = 22.5479 minutes, an average of service utility level = 81.23%, queue length = 3 persons, and the number of service personnel = 3 persons for annual tax payment services, while for five years tax payment services, the optimum condition for average waiting time = 42.85336 minutes, an average of service utility level = 91.38%, queue length = 5 persons, and the number of service personnel 2 persons.
Optimal Pressure Vessel Project Schedule Planning with Critical Path Method (CPM) at PT. XYZ Yustina Ngatilah; Caecilia Pujiastuti; Isna Nugraha; Dwi Qomariah Arifin
Nusantara Science and Technology Proceedings 2nd International Conference Eco-Innovation in Science, Engineering, and Technology
Publisher : Future Science

Show Abstract | Download Original | Original Source | Check in Google Scholar

Abstract

Project scheduling is one element of planning that provides various information for time efficiency to complete a project. The success of a project starts from the planning and preparation of the correct and systematic stages. Every company must try to complete the work on time as scheduled to avoid various losses that arise. This research aims to determine the activities that are classified as critical in the production of pressure vessels belonging to one of the leading companies in Indonesia engaged in natural gas processing, which PT is carrying out. XYZ. This study also compares the costs incurred to complete the pressure vessel project with a normal and accelerated duration of work. The method used is the Critical Path Method (CPM) and Microsoft Project software. CPM is a network analysis that aims to optimize the total project cost by reducing completion time. The use of the CPM method can save time in completing various stages of a project. The initial project duration is 952 working hours or 119 working days. It can be accelerated to 884 working hours or 111.25 working days, 7.75 days faster than the initial schedule. There are 24 critical activities, and the labor cost that must be spent is IDR 72,034,400.00 under normal conditions, while the labor cost that must be spent for the acceleration condition is IDR 76,626,400.00.
Co-Authors Aldo Buyung Pratama Aldo Buyung Setya Pratama Anasyah Septiara Angelia Tantyono Arief S, Purwanto Caecilia Pujiastuti Caecilia Pujiastuti Cyrilla Indri Parwati Desak Ayu Clara Dewanti Dimitra Izzati Putri Dimitra Izzati Putri Dina Rosidah Dwi Qomariah Arifin Dwi Sukma Donoriyanto Endang P. Widjajati Endang Pudji Widjajati Erlina Purnamawati Erlina Purnamawaty Farida Pulansari Frizkia Sepriandini Ichan Wahyuti Ichan Wahyuti Irma D. Pratiwi Isna Nugraha Ketut Sumada Caecillia Pujiastuti Laila, Indah Nur Laksono Trisnantoro Muhammad Septianto Nadya Annisa Wulandari Nadya Annisa Wulandari Nour Afifah Nour Afifah Nur Kholik Nur Kholik Nyimas Rihadatul Aisy Nyimas Rihadatul Aisy Primahesa, Ibad Guntur Pujiastuti , Caecilia Pujiastuti, Caecilia Pujiastuti, Caecilia Putri, Dinar Ismilla Ricky Eka Putra Rony Oktavianto Rr. Rochmoeljati Siati Syamsul Arifin Tranggono Tranggono Wahyu Setia Damayanti Wahyu Setia Damayanti Widya P, Vika Zenna Rasyid Y Zharfan Hamzah