Modeling

Multi-Objective Modeling for Determining Location of Undesirable Facilities

Jasenka Rakas
Teodorović, Dušan
Kim, Taehyung
2004

This paper develops a model for determining locations of undesirable facilities. It is formulated as multi-objective since the problem of locating undesirable facilities faces many conflicting criteria. A method is also proposed to appropriately address uncertainty associated with this class of location problems. The methodology developed in this study is tested using the real-world data.

Deterministic Models for Degraded Airside Capacity and Delays

Jasenka Rakas
Schonfeld, Paul
2004

This paper presents deterministic models for estimating airspace and airport capacity and delays during equipment outages. The National Airspace System (NAS) is very complex and consists of almost 48,000 reportable facilities and services that support air traffic control with very diverse functions and technologies. To better understand NAS performance and develop a methodology for estimating degraded capacity, previous studies about equipment outages and about airspace and airport performance are first reviewed. A deterministic aircraft separation model is used to estimate degraded...

Statistical Modeling and Analysis of Landing Time Intervals: Case Study of Los Angeles International Airport, California

Jasenka Rakas
Yin, Huifang
2005

Existing literature suggests that analyses of landing time intervals employ simple statistical models based on time-separation histograms, usually approximated by normal distributions. Although the literature focuses on important issues such as safety, capacity improvements, and separation rules, it does not take into account another important issue: the possible, unique behavior of airlines, pilots, and controllers. In this study such possible, unique behavior is taken into account and a statistical analysis on landing time intervals is performed to find the operational properties of Los...

Airport Availability Modelling: A Different Perspective

Jasenka Rakas
Hecht, Myron
2007

This study proposes a systems-level approach to airport and runway availability assessments and prediction, and addresses the problem of the aging or continuously degrading aviation infrastructure. Although the availability block diagrams are often used in the availability assessment of aerospace and electronic systems, their application to the airport availability problem on a system level, developed in this study, is novel. The proposed methodology is intended for short-term and long-term planning of the Communication, Navigation and Surveillance (CNS) equipment acquisition, and...

Modeling the Impact of Equipment Outages on National Airspace System Operations

Jasenka Rakas
Yin, Huifang
2012

This study is part of a larger effort initiated by the FAA’s System Capacity Office, Capacity Initiative Division, toward developing a methodology for assessing airport performance and establishing airport efficiency metrics for runway and airport utilization.

Methodology for Estimating Terminal Airspace Service Availability and System Effectiveness

Jasenka Rakas
Mark Hansen
2012

This paper develops a methodology for modeling the terminal airspace service availability and system effectiveness.

Climate Adaptation Strategies for California Airports Will Require a Holistic Approach, Including New Governance Models

Lindbergh, Sarah, PhD
Reed, Jackson
Takara, Matthew
Aparri, Aidan
Jasenka Rakas
2022

Airports are complex social, technical, and environmental systems. Understanding their complexity is fundamental for advancing transformative climate adaptation policy. For airports to adapt, climate science must be incorporated not only into standards of specific equipment and facilities, but also into the air traffic network and its interconnected infrastructure systems (e.g., road access, ground-based communications, navigation, and surveillance systems). In addition, airport adaptation requires a shift in the way policy is designed, reinforced, and updated, which in turn relies on an...

Controller-Pilot Voice Communication and Intent Monitoring for Future Aviation Systems Safety

Jasenka Rakas
Vallioor, Vishali Kirthi
Krozel, Jimmy
Kostiuk, Peter F.
Mohen, Michael T.
2024

In this study, a set of models and software are developed to support Aviation System Safety Analysis tasks. Three primary models are utilized to conduct the following analyses: (1) Speech Attribute analysis, (2) Speech-to-Text analysis, and (3) Intent Inference analysis. We analyze air traffic controller-pilot speech attributes and transcribed texts of voice messages to gain additional insights into controller-pilot communication dynamics. Such analyses are integrated with situation assessment modules to identify any anomalies in flight trajectories. Key speech attribute patterns are...

A Model for Selecting the Best Sustainable Airport Technology Alternatives

Tchivwila, Moïse Biampata
Jasenka Rakas
Hendrickson, Thomas P.
Nikolic, Milos
2025

Air transport is a continually expanding industry, a fact that has become even more evident with the recovery of the aviation industry post-COVID-19. This expansion amplified energy consumption at airports, which was already significantly high. Airport decision-makers are increasingly focusing on improving sustainability and addressing social, economic, and environmental criteria across airports worldwide. In this article, we propose a decision-making model for identifying a sustainable airport technology solution that minimizes the energy consumption of airport lighting while considering...

Robustness of Boundary Observers for Radial Diffusion Equations to Parameter Uncertainty

Camacho-Solorio, Leobardo
Scott Moura
Krstic, Miroslav
2018

Boundary observers for radial diffusion equations can be derived to achieve exponential convergence of the estimation error system provided that coefficients are known; which can be either constant or possibly spatially and time varying. When the coefficients depend on the state, their values are not longer known and this might prevent the estimation error to converge to zero. Here, we address the state estimation problem for a radial diffusion equation in which the diffusion coefficient depends on the spatial average of the state value; using an observer with a constant diffusion...