Ali Akgunduz

• Doctor of Philosophy
• Concordia University

This paper proposes for the first time a unified optimal approach to solve a direct operating cost (DOC) minimization problem where the cost index (CI) is time-varying. More specifically, the coefficient CI is modeled as a time-varying parameter commanded by Air Traffic Control (ATC). The proposed unified approach relies on the solution of an optim...

The COVID-19 pandemic exposed the vulnerability of the Canadian economy on many fronts. When the demand for lifesaving equipment increased globally, the supply chain networks were broken by the direct involvement of other countries. The rising competition and interruptions caused Canada to face significant difficulties in global markets to secure c...

In response to evolving societal and technical demands, this research explores the dynamic landscape of product evolution, focusing on the case study of braking systems. Acknowledging the critical role of product evolution analysis in design phases, the study introduces the Environment-Based Design (EBD) methodology. EBD emphasizes environmental an...

The COVID-19 pandemic exposed the vulnerability of the Canadian economy on many fronts. When the demand for lifesaving equipment increased globally, the supply chain networks were broken by the direct involvement of other countries. The rising competition and interruptions caused Canada to face significant difficulties in global markets to secure c...

Project-based design method is widely used in engineering design education. However, it is time-consuming to develop design thinking skills through projects. This paper proposes that learning methodology and projects will significantly improve students' learning experience and outcomes. The TASKS framework is used to analyze the pros and cons of th...

Project-based design method is widely used in engineering design education. However, it is time-consuming to develop design thinking skills through projects. This paper proposes that learning methodology and projects will significantly improve students’ learning experience and outcomes. The TASKS framework is used to analyze the pros and cons of th...

This paper aims to improve students’ learning performance by optimizing their mental stresses in learning through proposing a new course timetabling method. This new method is based on two hypotheses that formulate the link between course timetabling and learning experience: i) a student’s learning performance is superior when the student is subjec...

Aircraft taxiing with external electric towing could significantly reduce carbon dioxide (CO2) emissions from ground operations. We develop a discrete event simulation and cost model to investigate taxiway congestion and develop a comprehensive equivalent annual cost (EAC) estimate from using electric towing tractors (e-tractors). The model incorpo...

Air travel industry is among the most and the oldest beneficiaries of the Operations Research tools. The literature in the field of airline revenue management has been steadily growing over four decades. This paper presents a structured literature review of the peer-reviewed publications in the area of Revenue Management in the airline industry. Th...

Among several crucial objectives of the air transportation system, minimization of fuel consumption has a profound impact on the economic viability of airline companies and their effect on the environment. Given that many large airports around the world are located in the heart of residential areas such as Chicago’s O’Hare, New York’s JFK, and Mont...

Aircraft en-route flight planning is one of the major challenges for Air Traffic Control operations. Poor planning results in undesirable congestion in the air-traffic network, causing major economic losses for both airline companies and the public. Furthermore, heavy congestion generates flight safety risks due to increased possibility of mid-air...

This paper discusses the challenges in achieving bio-signal-based design environments. While the main motivation of this paper was to provide a user interface for physically disabled people to express their artistic natures, a special emphasis is given on graphical user interface design where bio-signals are the single input source. Among three bio...

This paper discusses a unique formulation for the en-route flight planning problem in a constrained airspace with the objective to minimize costs incurred from earliness, lateness, and fuel-consumption, and to ensure flight safety. Mid-air conflict and collision avoidance, and also minimum separation distance between aircraft and speed-dependent fu...

Course scheduling is a challenging operations research problem that involves students, faculty members, availability of classrooms, class sizes and many other factors. As it is the case for most scheduling problems, course scheduling is an NP-Hard problem. Due to its challenging nature, frequently the main objective is only to find a feasible solut...

Course scheduling is a challenging operations research problem that involves students, faculty members, availability of classrooms, class sizes and many other factors. As it is the case for most scheduling problems, course scheduling is an NP-Hard problem. Due to its challenging nature, frequently the main objective is only to find a feasible solut...

The purpose of this study is to use Health Belief Model (HBM) concepts to predict public's intentions to develop protective behaviors toward seasonal influenza (vaccination and social-distancing) and to explore the effect of education (awareness) programs on individual's protective behaviours. In order to study individual's behaviours toward develo...

The objective of this paper is to introduce COGAF (a Common Graduate Attributes management Framework), an end-to-end framework that can be used by Canadian higher-level education institutions for integrating and managing the assessment of CEAB (Canadian Engineering Accreditation Board) graduate attributes in a systematic manner. COGAF is designed a...

As many as one in three first-year undergraduate students cannot make it back for the sophomore year. The low retention rate for students, especially engineering students, is a widespread problem. In this paper, the quantification of course difficulty and student stress is discussed, followed by a student stress model which can integrate student st...

It is well established in the epidemiological literature that individual behaviors have a significant effect on the spread of infectious diseases. Agent-based models are increasingly being recognized as the next generation of epidemiological models. In this research, we use the ability of agent-based models to incorporate behavior into simulations...

This paper discusses the challenges towards achieving bio-signal based design environments. While the primary objective is to provide user-interface for disabled people for artistic expression, special emphasis is given to the design of graphical user interface where bio-signals are the predominant input sources. Among three unique solution methodo...

Economic lot sizing problem (ELSP) is one of the most studied problems in production planning and it deals with the scheduling of a set of products in a single machine to minimize the long run average holding and setup cost under the assumptions of known constant demand and production rates. In this study, since the traditional deterministic ELSP m...

An automotive seat must provide the occupant with a comfortable environment in which driving can be performed in a safe and comfortable manner. The characterisation of the interactions between the occupant and the seat under various conditions thus constitutes an important goal for enhancing the knowledge of essential design factors that could yiel...

We developed an agent based simulation using Arena software to model the effect of vaccination and self-isolation as two strategies for preventing the spread of influenza. We then evaluated the results of this model within the context of probabilistic cost effectiveness analysis, enabling us to inform policy makers with a contextualized view of the...

In 2009 the Canadian Engineering Accreditation Board (CEAB) announced its intention requiring all undergraduate engineering programs in Canada to utilize twelve graduate attributes for assessing the capacities of its students. In response, engineering faculties across the country have been experimenting with creating processes that incorporate thes...

We propose a new dynamic row/column management algorithm for the schedule of freight trains in a single/double track railway system. While many works have already been devoted to train scheduling, previously published optimization models all suffer from scalability issues. Moreover, very few of them consider the number of alternate tracks in the si...

In computer graphics, the construction of complete 3-dimensional objects requires the blending of several incompatible (mathematical properties are different) surface patches such as Bezier, B-spline, and NURBS surfaces. The blending process often results in undesirable geometric properties along the connected boundaries such as sharp edges, gaps,...

Understanding of user needs and preferences, and incorporating them into product designs are crucial for new products to be successful in today's highly competitive marketplace. This paper introduces a unique methodology to capture user preferences from biological signals. The proposed method successfully utilizes one of the most complex phenomenon...

We propose a new dynamic row/column management algorithm for freight train scheduling in a single track railway system. While many papers have already been devoted to train scheduling, previously published optimization models still suffer from scalability issues, even for single track railway systems. Moreover, very few of them take into account th...

This paper discusses the scheduling of operators on work elements in manufacturing environments where lean principles are adopted. Our experience with the industry revealed that the practice of lean manufacturing in organizations that manufacture oversized products, such as buses, aircrafts and locomotives differs from other organizations. The most...

It is known that a through understanding of the end-user is the most valuable information to improve design, training, maintenance and assembly/disassembly processes of products and systems. The most widely used method to analyze human-system interaction, user experiments, which requires a product prototype, a test environment and a researcher to w...

This article addresses an airline revenue management strategy to jointly determine both the seat allocation and the fare price for a single leg flight in a duopoly market. Two game theoretic scenarios: non-cooperative and cooperative are considered. In non-cooperative game setting, existence of pure strategy Nash Equilibrium for the perfect competi...

In this paper, we analyze Engineering Changes (EC), which are modifications in forms, fits, functions, materials, or dimensions in components constituting the design. We propose a new approach for processing these changes within a Virtual Collaborative Design Environment. This environment, named Active Distributed Virtual Change Environment (ADVICE...

The Economic Lot Scheduling Problem (ELSP) has been well-researched for more than 40 years. As the ELSP has been generally seen as NP-hard, researchers have focused on the development of efficient heuristic approaches. In this paper, we consider the time-varying lot size approach to solve the ELSP. A computational study of the existing solution alg...

In this paper, a new modeling approach based on a sliding manifold and hybrid system formulation, is developed to describe the dynamics of interacting rigid body systems. Appropriate discrete states, events, reset maps, and threshold parameters are developed. These yield a hybrid automaton framework to describe interacting rigid body systems. The n...

This paper introduces a virtual reality (VR) based automated end-user behavioural assessment tool required during product and system development process. In the proposed method, while VR is used as a means of interactive system prototype; data collection and analysis are handled by an event based system which is adopted from human–computer interact...

This paper studies a horizontal fare-pricing competition between two airlines having a single flight leg. Two distinct scenarios are considered. First, the two airlines price competition for the pre-committed booking limits is analysed. The problem is studied under deterministic price sensitive demands. The existence of unique pricing strategies at...

This paper investigates the potential of using the financial options as a means of managing the ticket sales in an airline booking process. Call options are used to recall the tickets already sold, whereas put options are exercised to sell low-fare tickets in the last booking period whichever is favourable to the airline. By utilising the proposed...

The economic lot scheduling problem has driven considerable amount of research. The problem is NP-hard and recent research is focused on finding heuristic solutions rather than searching for optimal solutions. This paper introduces a heuristic method using a tabu search algorithm to solve the economic lot scheduling problem. Diversification and int...

In this paper, a new methodology for surface reconstruction from sets of points for reverse engineering is described. The sets of points are obtained using stereovision techniques. Techniques for minimizing the number of images required for a complete object reconstruction are explored based on characterizing the shapes to be recovered in terms of...

Economic lot scheduling problem has been an important topic in production planning and scheduling research for more than four decades. The problem is known to be NP-hard due to it’s combinatorial nature. In this paper, two meta-heuristics algorithms – Tabu Search and Simulated Annealing – are proposed. To investigate the effect of control parameter...

This paper addresses the issue of real-time collision detection between pairs of convex polyhedral objects undergoing fast rotational and translational motions. Accurate contact information between objects in virtual reality based simulations such as product design, assembly analysis, performance testing and ergonomic analysis of products are criti...

This paper describes a technique for tracking-based reconstruction from camera images. The position and orientation data are provided by a commercial laser tracker rigidly attached to the camera. The tracker enables the determination of the extrinsic camera parameters. Focal length is automatically calibrated in parallel with the depth computation...

This paper discusses a two-step virtual reality based conceptual design tool that enables industrial designers to create sketches of their ideas in 3-dimensional space in real time. In the developed sketching tool, the rough shapes of products are generated by tracing the trajectory of the data-gloves worn by the designer. In the model a practical...

In this chapter, an efficient technique for distributing the data in collaborative virtual reality simulations is presented. The technique described incorporates the culling and level of detail concepts in virtual reality (VR) to obtain cell-based bounding volumes in each virtual environment. Defined bounding volumes are utilized in filtering the d...

In this technical note we survey the area of smart collision information processing sensors. We review the existing technologies to detect collision or overlap between fast moving physical objects or objects in virtual environments, physical environments or a combination of physical and virtual objects. We report developments in the collision detec...

In this paper, a sub-component selection methodology for product design is described. The described technique incorporates the analytic hierarchy process and linear goal programming into the process of evaluating alternatives for sub-components and parts, which enables the design of products by satisfying customer, technical, and financial requirem...

In this paper an efficient technique for distributing the data in collaborative virtual reality is presented. The described technique incorporates the culling and level of detail concepts in virtual reality to obtain cell based bounding volumes in each virtual environment. Defined bounding volumes are utilized in filtering the data that is transfer...

This paper describes an algorithm for surface reconstruction from a set of scattered three-dimensional points extracted from an image sequence. In this process, additional information (such as location of the viewpoints and the points visible from a particular viewpoint) is available and can be exploited for accurately recovering the shape of the o...

The fast construction of a Virtual Factory model without using a CAD package can be made possible by using computer vision techniques. In order to create a realistic Virtual Manufacturing environment, especially when such a model has to be created in correlation to an existing facility, a reliable algorithm that extracts 3D models from camera image...

The fast construction of a Virtual Factory model without using a CAD package can be made possible by using computer vision techniques. In order to create a realistic Virtual Manufacturing environment, especially when such a model has to be created in correlation to an existing facility, a reliable algorithm that extracts 3D models from camera image...

Thesis (Ph. D. in industrial engineering and operations research)--University of Illinois at Chicago, 2001. Vita. Includes bibliographical references (leaves 89-94). Typescript (photocopy).