Article Per Year (5 Year)
p-Index From 2020 - 2025
0.23
P-Index
This Author published in this journals
All Journal Journal of Mathematical and Fundamental Sciences Communication in Biomathematical Sciences
Edy Soewono
Department of Mathematics, Institut Teknologi Bandung
Astronomy Chemistry Earth & Planetary Sciences Mathematics Physics Social Sciences

Published : 6 Documents Claim Missing Document
Claim Missing Document
Check
Articles

Found 2 Documents
Search
Journal : Journal of Mathematical and Fundamental Sciences

 1 
Optimization Model for an Airline Crew Rostering Problem: Case of Garuda Indonesia Rieske Hadianti; Khusnul Novianingsih; Saladin Uttunggadewa; Kuntjoro A. Sidarto; Novriana Sumarti; Edy Soewono
Journal of Mathematical and Fundamental Sciences Vol. 45 No. 3 (2013)
Publisher : Institute for Research and Community Services (LPPM) ITB

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.5614/j.math.fund.sci.2013.45.3.2

Abstract

This paper discusses the cockpit crew rostering problem at Garuda Indonesia, taking into account a number of internal cockpit crew labor regulations. These internal labor regulations are in general more restrictive at Garuda Indonesia than at other airlines, so that modeling the cockpit crew rostering problem for Garuda Indonesia is challenging. We have derived mathematical expressions for the cockpit crew labor regulations and some technical matters. We model a non-linear integer programming for the rostering problem, using the average relative deviation of total flight time to the ideal flight time as the objective function. The optimization model have been tested for all classes of cockpit crews of Garuda Indonesia, using a simulated annealing method for solving the problem. We obtained satisfactory rosters for all crew members in a short amount of computing time. This shows that the optimization problem is well-defined.
On the Interaction between Trichogramma chilonis and Jatiroto Flies with Stem Borer Pests in Sugarcane Plantation Fauzi, Rifky; Mufidah, Zunanik; Maretta, Gres; Edriani, Tiara Shofi; Rizka, Nela; Mukhaiyar, Utriweni; Utami, Riani; Haryani, Sri; Saefudin, Saefudin; Styaningrum, Amalia; Soewono, Edy
Journal of Mathematical and Fundamental Sciences Vol. 56 No. 3 (2024)
Publisher : Directorate for Research and Community Services (LPPM) ITB

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.5614/j.math.fund.sci.2024.56.3.3

Abstract

Pests in sugarcane plantations are a major cause of damage, which could lead to severe damage to the crop, reduction of sugar quality, and significant economic loss. One of the major pests known in sugarcane plantations is stem borer (Chilo sacchriphagus), which attacks the canes. Two primary parasitoids, Trichogramma chilonis, which predates the stem borer eggs, and the Jatiroto fly (Diatraeophaga striatalis), which predates the stem borer larvae, are discussed here. This paper presents a time-dependent ten-dimensional dynamical mathematical model consisting of four-stage stem borer compartments, three-stage Trichogramma compartments, and three-stage Jatiroto compartments. Simulations are presented to describe the phenomenon of Trichogramma predation, Jatiroto predation, and simultaneous predation of both predators. It is shown that the release rate of each predator and a combined release of two predators can significantly reduce the infestation levels to a tolerable level for sugarcane production. The oscillatory dynamics of the stem borers and the Jatiroto flies affected the release timing strategy based on the level of infestation in the field. The results are expected to help us better understand the predator-prey phenomenon in the field and improve the forecasting of infestations in the field.
Co-Authors Edriani, Tiara Shofi Gres Maretta, Gres I Gusti Bagus Wiksuana Khusnul Novianingsih Kuntjoro A. Sidarto Mia Siti Khumaeroh Mona Zevika Mufidah, Zunanik Novriana Sumarti Nuning Nuraini Oliver T.C. Tse Rieske Hadianti Rifky Fauzi Rizka, Nela Saefudin Saefudin Saladin Uttunggadewa Sri Haryani Styaningrum, Amalia Tse, Oliver T.C. Utami, Riani Utriweni Mukhaiyar Zevika, Mona