Current Research
Antonio Celio P. Mesquita
03072248800

Qualification exam
May 25, 2022

Defense date
May xx, 2023

Advisor
Carlos Alberto Alonso Sanches

Type
Doctorate
Abstract
In the scenario of aerial pickup and delivery of goods in a distribution network, transport aviation faces risks of cargo unbalancing due to the urgency required for loading for rapid take-off and mission accomplishment, especially in times of crisis, public calamity, client contract short lead times, or any external pressure for immediate take-off. We contributed by modelling and solving a new problem of planning the loading and routing of an aircraft according to a utility score, weight and balance principles, and fuel consumption in a tour of simultaneous pickup and delivery at intermediate airfields. This difficulty encompasses four sub-problems: Air Palletization; Weight and Balance; Pickup and Delivery; and Vehicle Routing. This new hard problem, named Air Cargo Load Planning with Routing, Pickup, and Delivery Problem (ACLP+RPDP), is mathematically modelled using standardised pallets in fixed positions, obeying the centre of gravity constraints, delivering each item to its destination, and minimising fuel consumption costs. We also contributed by carrying out multiple experiments with a commercial solver and four well-known meta-heuristics on synthetic data based on real data from the Brazilian Air Force's transportation. These challenging benchmark instances are made publicly available. We also created a heuristic that quickly finds good solutions for a wide range of problem sizes, an essential contribution as it was the unique method that managed to solve all testing scenarios. (222 words)
Provisional title
Air cargo load and route planning in pickup and delivery operations

Research problem
There is no technological assistance to help the load and trip planners with the huge number of demands for transport in each hub. This enables risks of cargo unbalancing, improper delivery, excessive fuel burn, and more than 2 hours of TAT for airlift missions. It is necessary to solve an Air Paletization, a Weight and Balancing, a Pickup and Delivery, and a Routing Problem, all simultaneously.
Daniel Buch
04425005996

Qualification exam
March 11, 2022

Defense date
March xx, 2023

Advisor
Fernando Teixeira Mendes Abrahão

Type
Master
Abstract
Complex systems, such as aircraft and combat vehicles, have a high life cycle cost, potentiated by their long-life expectancy in service. This characteristic makes relevant to forecast the costs of the operation and support phase, which, in general, is the most costly and long-lasting phase of the life cycle. Given that it is in the early stages of a product's development that life cycle cost savings opportunities are concentrated, it is in these stages that different design alternatives must be evaluated, considering their impact on the cost of operation and support, before being selected and integrated into the product. In this context, this work proposes a method to support trade-off studies, to be applied in the early stages of development, based on modeling the supportability aspects of design alternatives in compliance with an operation concept. The models are then submitted to the simultaneous optimization of the support strategy, resource allocation, location of inventories and their levels, allowing detailed cost comparisons, after the optimization results have been submitted to simulation, which introduces the dynamism of the operation. of the system. The application of the method to a case study, which evaluates the integration of design solutions to an aeronautical engine under development, illustrated the potential of the method to support decisions in the early stages of the life cycle. (218 words)
Provisional title
Modeling and simulation in support of design solutions integration decisions based on their lifecycle cost impacts.

Research problem
The problem is to figure out how different project alternatives affect operation and support costs, taking into account the concept of operations and supportability issues.
José Nogueira M. Filho
37264559734

Qualification exam
Ago. 2022

Defense date
May xx, 2023

Advisor
Fernando Teixeira Mendes Abrahão

Type
Doctorate
Abstract
When planning maintenance for complex systems, clients need to assure that system is safe for the operation, that it can accomplish the planned missions in a cost-effective way. The problem is that initial maintenance planning is conservative due to lack of a maturity data and tools to support the maintenance engineers that follow MSG-3 guidelines for maintenance task analysis and maintenance plan design, strictly using their best “engineering judgment”, which may result in inefficient maintenance plans, i.e., more costly than they could be, and with lower than possible availability and dispatchability. As aviation costs are one of the highest in the industry, even a small amount of savings could represent a great amount of money in the long run. This study adds to the research on complex system maintenance by looking at how an optimization model and field or usage data could be used to make maintenance plans that are smart and reliable. An optimal maintenance plan must associate tasks to maintenance packages and preparation tasks in many cycles along the airliner's life span. We extend the study on Task Allocation Problem (TAP) by evaluating the possibility of these optimizations with supervised learning on historical data to construct a resilient maintenance plan. The results proved that the model task grouping associated with machine learning reduces total maintenance costs in the long run. The results also revealed little influence of repair probability on aeronautical components in the optimization model. (238 words)
Provisional title
Data Learning guided optimization model for tasks to maintenance package allocations

Research problem
Maintenance planning is conservative due to limitations faced by maintenance engineers, such as the absence of an efficient tool to complement the MSG-3 analysis and support the allocation of tasks during the design of the operator’s maintenance plan, a Task Allocation Problem (TAP), which may result in inefficient maintenance plans, i.e., more costly than they could be, and with lower than possible availability.
João Henrique Amorim de Almeida
40547985860

Qualification exam
Nov xx, 2022

Defense date
Jun xx. 2023

Advisor
Fernando Teixeira Mendes Abrahão

Type
Doctorate
Abstract
The flight tests of the aeronautical certification process, in addition to being complex and time-consuming, represent one of the highest costs due to several elements such as: qualified labor, infrastructure and specific computational resources. These are crucial to ensure that the data collected meets the requirements required by aviation authorities. The methods of conducting the tests directly influence the planning. With that, this article analyzes the flight test tasks, using operational research, applying the requirements with the constraints and logical relationships involved to verify the compatibility, sequencing, cost and qualitative analysis. (91 words)
Provisional title
Analysis of Operational Research Methods to Reduce Time and Cost of Aerospace Systems Flight Test Tasks

Research problem
The problem is that the tasks of flight tests of aerospace systems have high costs and time to perform. This is due to variables that go beyond the numerous requirements. In addition, there is no defined rule or method for planning and executing tests. So each manufacturer does it the way their team sets out, and the less experience they have, the more likely manual modes are, making a longer and more expensive path.
Lucas Sales Martins
06381933461

Qualification exam
Feb. 23, 2022

Defense date
Feb. xx, 2023

Advisor
Fernando Teixeira Mendes Abrahão

Type
Master
Abstract
This research is part of the theme of "supportability of complex defense systems", bringing a literature review about Integrated Product Support (IPS). In the face of the challenge faced by managers in decision-making processes regarding the allocation of resources, including financial ones, to increase the efficiency of logistical support to these systems, the question emerges that summarizes the problem of this research: "How to identify the contributing factors to be prioritized for improved supportability”? Therefore, the general objective of this work is to develop a method that aims to evaluate the impacts of logistical factors on the supportability of military aircrafts, based on modeling and simulation, to classify them in a ranking that indicates, systemically, which actions or alternatives are more efficient. The strategy to achieve the outlined objective consists of a combination of the Prospective Life Cycle Cost Calculation Method with the Value-Based Support Strategy Assessment Model. In an overview, the solution pointed to the research problem is composed of a comparative analysis between an initial reference scenario and the projected conditions of alternative scenarios, obtained by the controlled variation of the considered factors. The application of the method is tested in a case study inspired by a fleet of aircrafts of the Brazilian Air Force, from which it is possible to verify the impacts of 7 logistical factors on operational availability and support cost, fundamental metrics of supportability. The academic relevance of the work finds operational application in revisions of the support solution, insofar as the evaluation method can be used as an analysis and advisory tool. Although the tests were carried out with defense aircraft, the application is naturally applicable to other complex systems. | 277 words
Provisional title
Evaluation of the Impacts of Logistic Factors on the Supportability of Military Aircrafts.

Research problem
Managers of complex defense systems are often faced with decision-making processes to increase the efficiency of logistical support in terms of operational availability and support cost. Faced with this challenge, the problem of this research is the limitation of the methods available in the literature regarding the identification of contributing factors, related to the elements of Integrated Product Support (IPS), to be prioritized in the allocation of resources to improve supportability.
Luciana Guaracy de Oliveira
06135856669

Qualification exam
Aug. 11, 2022

Defense date
Jul. xx, 2023

Advisor
Fernando Teixeira Mendes Abrahão

Type
Master
Abstract
One of the dilemmas faced by airlines is choosing how best to use their aircraft. Operating a fleet with a high rate of aircraft utilization seems to be a better choice from the point of view of diluting fixed costs, but it may not be valid in the medium and long term. The literature is unclear as to a method for sizing a fleet through a systemic and long-term view, taking into account all elements of integrated product support. This article models, through a case study, the use of a fleet with all its support systems and performance indexes (availability versus costs) to compare different strategies for its dimensioning, considering the life cycle as a whole. As a result, it can be seen that a larger fleet size leads to a reduction in life cycle costs. (136 words)
Provisional title
Smart fleet sizing by modeling and integrating utilization data and information.

Research problem
There is a risk in fleet management regarding the utilization level chosen that may result in aircraft exhaustion or underutilization. The problem is that it is not known how to establish the ideal interval where this choice may be more efficient for the management of the aircraft life cycle as a whole.