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UTSG: Decomposing Optimization Problems Under Stochastic Disruptions

This event is open to the public and registration is not required. Part of the Operations Research Seminar Series coordinated by Merve Bodur.


A stochastic disruption is a type of infrequent event in which the timing and the magnitude are random. We introduce the concept of stochastic disruptions and a stochastic optimization framework is proposed for such problems. In this talk, we present a special example: a project crashing problem under a single disruption. When a disruption occurs, the duration of an activity, which has not yet started, can change. Both the magnitude of the change of an activity’s duration and the timing of the disruption can be random. We prove that it is NP-hard to optimize the expected project span for this crashing problem, and illustrate its properties via examples. We formulate a stochastic mixed integer program (SMIP) with mixed integer recourse. This SMIP is computationally challenging to solve using existing techniques. We propose an adaptive branch-and-cut algorithm to solve the SMIP and evaluate the computational performance of our approach. Further extensions of such optimization models under stochastic disruptions can be applied to power system operations.

Speaker Bio

Haoxiang Yang is joining the Center for Nonlinear Studies (CNLS) at Los AlamosNational Laboratory as a post-doc research associate. His research focuses on the modeling and decomposition algorithms of optimization under uncertainty, specifically in stochastic programming and robust optimization, with applications in supply chain and logistics, disaster relief, and energy systems. He holds a PhD degree in Industrial Engineering and Management Sciences from Northwestern University and a bachelor’s degree in Industrial and Systems Engineering from Georgia Institute of Technology.


The Operations Research (OR) seminar series brings together graduate students, faculty and researchers from the University of Toronto community to interact with prominent scholars in the field of OR. Seminars feature visiting scholars from around the world as well as professors and post-docs. Topics include all variants of OR theory and their applications. Questions? Contact Merve Bodur at

Blue Sky Solar Racing unveils new solar-powered race car

Viridian will compete in race of over 3000 kilometres across Australia

Blue Sky Solar Racing unveils new solar-powered race car

A team of U of T Engineering undergraduate students named Blue Sky Solar Racing unveiled Viridian, the 10th generation of its solar-powered race car, in its first public unveiling event on June 24.

For over 22 years, different compositions of the team designed, built, and raced solar-powered cars, creating a new generation every two years.

This year, Blue Sky Solar Racing completed the design and manufacture of Generation X. The vehicle was showcased to the public for the first time at Myhal Centre Auditorium.

Race car’s manufacture celebrated by keynote speakers

The buzzing audience included team alumni, sponsors, and staff from the Faculty of Applied Science & Engineering. Around 200 guests attended in total.

Following an introduction by Managing Director Hubaab K. Hussain, two professors delivered remarks onstage.

Professor Amy Bilton, the Director of the Centre of Global Engineering, discussed her experiences as an alumna of Blue Sky Solar Racing. She reflected on her involvement as the Aerodynamics Team Lead in 2006, and noted that the team puts in an incredible amount of effort each year.

“[The team members] are basically doing more than a full-time job at the same time as they are doing a full load of engineering courses,” she said.

Professor Cristopher Yip, the Dean of the Faculty of Applied Science & Engineering, also spoke at the event, and congratulated the team on their successful manufacture of Generation X.

The unveiling of Viridian onstage

In a wave of applause, team members pulled back the curtain to reveal their feat of design.

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Viridian is a boat-shaped solar-powered race car with a length of approximately three metres. The hood of the vehicle is covered with an array of solar panels. A glass hemisphere swells from the middle of the car, serving as the windshield.

In an interview with The Varsity, Hussain said that Viridian can reach a top speed of 120 kilometres per hour according to previous testing.

He said that the team continues to work on testing and characterizing the car ⁠— in addition to getting some much-needed sleep. This will be in preparation for racing Viridian in the international Bridgestone World Solar Challenge this autumn.

Racing 3000 kilometres in Australia

Viridian’s race will be the seventh time that the team’s vehicle will make the cross-continental trip from Darwin to Adelaide in Australia. Travelling north to south of the country, Viridian will race a course of 3000 kilometres.

The competition is set to begin in October. Before then, the team will repeatedly test the car to get as much characterized information about its performance as possible. Details such as its power consumption at certain speeds, as well as how certain environmental conditions affect Viridian’s performance, are especially valuable.

Potential commercial applications

Outside of racing competitions, solar-powered cars have an immense commercial potential. Hussain highlighted Lightyear, a start-up electric car manufacturer in the Netherlands.

The European company released their first solar-powered electric car on the same day as Blue Sky Solar Racing’s unveiling event. Its new car, named Lightyear One, is set to be released on the market soon, with a listed price of €149,000 in the Netherlands, roughly equivalent to 218,400 CAD.

In addition to developing solar-powered race cars, Hussain said that Blue Sky Solar Racing also aims to provide opportunities to enrich the experiences of undergraduates.

“The [goal] of the [Blue Sky Solar Racing],” said Hussain, “is to provide students with an opportunity to grow and develop outside of the classroom, as well as promote sustainable technology.”

U of T team wins top prize at KPMG’s international AI competition

Paramount AI team created device that sorts waste with 94 per cent accuracy

U of T team wins top prize at KPMG’s international AI competition

A team of five U of T graduate students named Paramount AI won first place in KPMG’s 2019 Ideation Challenge, a worldwide competition to develop solutions to problems facing businesses using artificial intelligence (AI). KPMG is one of the world’s top four accounting firms.

The U of T students faced off against 600 participants from top universities across nine countries, including Canada, Australia, China, Germany, Luxembourg, Italy, the Netherlands, and the United Kingdom.

The final round was held from May 10–12 in Amsterdam, where the students — Maharshi Trivedi, Nikunj Viramgama, Aakash Iyer, Vaibhav Gupta, and Ganesh Vedula — won the top prize for their innovation, which used AI to automate waste segregation.

Paramount AI’s innovative solution

The winning innovation is a sorting system able to distinguish between three different categories of waste: recycling, organic, and garbage.

Iyer, who is specializing in data analytics and financial engineering, explained that the initial prototype of the system used LED light bulbs and basic circuits to classify the waste.

The five students worked continuously, with little breaks and limited sleep during the three days of the competition, which came at the expense of exploring Amsterdam.

The reward for their efforts came in the confirmation of the practicality of using the system in real-life situations. The device completed both a financial and market analysis by the end of the competition.

The importance of waste segregation

Viramgama, who is specializing in data analytics and data science, explained that the team chose to focus on the issue of waste segregation because they were concerned about improper sorting in Toronto.

He noted that about one in three residents in Toronto contaminate the waste they place in recycling bins, and that 20 per cent of waste placed in blue recycling bins ends up in a landfill.

Since there is limited landfill space, this has motivated government spending on improved waste management. An increase in spending may lead to a raise in taxes,which makes the emergence of automation in waste segregation something that can greatly benefit our waste management.

The U of T team tackled this issue by creating a system that accurately sorts waste about 94 per cent of the time. Current waste systems have an accuracy of only up to 74 per cent, and each percentage of accuracy translates to significant savings for spending on waste management.

The pressing need for a solution to this environmental problem, which has economic consequences, could be a reason why Paramount AI won the competition.

The other reason, explained Vedula, was that the team was “not only thinking about saving the environment, but… also trying to help businesses [maximize] profits.”

The future of Paramount AI

The next step for Paramount AI is to present their prototype to experts at KPMG’s annual AI summit in October. By then, the team hopes to further develop their model, aiming to continue increasing the accuracy of their system, while likely adding new features to increase the value of the product for potential clients.

The students currently have the intellectual property rights of their invention. With the support of KPMG, the team is interested in looking to commercialize their product.

They are also optimistic about the future of AI in positively shaping the lives of Torontonians, as a whole. “We completely believe that in the next few years, we will see AI being integrated in every part of our lives, because there is a huge potential,” said Vedula.

“[AI] is already involved in making our lives easier.”

U of T team wins McMaster designathon

Undergraduates design method to protect cameras on military aircraft

U of T team wins McMaster designathon

A team of U of T students won first place at the Mac Design League Designathon 2019 hosted at McMaster University in January, with a design for shielding cameras on surveillance aircraft.

The team, dubbed “The Avengineers,” was composed of undergraduate students Nick Bajaikine, Kyle Damrell, Christopher Tong, and Mubtaseem Zaman, each enrolled in engineering programs.

Over a period of 36 hours from January 1920, they competed against 243 other students from across Ontario to solve real-world problems presented by industry sponsors of the event.

McMaster’s designathon was originally created in response to the popularity of hackathons.

Whereas hackathons focus on programming skills, the Mac Design League sought to create a multidisciplinary outlet for students to showcase their talents in mechanics and design. Featured challenges included designing EpiPens and lunar rovers.

The victorious U of T team was tasked with designing a way to shield cameras attached to the bottom of military planes from being damaged in the event of landing-gear failure or ‘soft-crash’ landing. The challenge was posed by aerospace imaging firm L3 Wescam,  an aerospace imaging firm which works with defence and military agencies around the world, posed the challenge to the team.

“Intuitively, the idea that comes in [first] is to make a mechanism that pulls the camera inside the aircraft and keeps it safe, like an elevator mechanism,” said Zaman in an interview with The Varsity. Zaman explained that many of their opponents attempted solutions along these lines. However, the team eventually noticed that such a solution might not be easy to adapt to other planes.

Zaman said that their next idea, which involved releasing the camera when it senses an impending crash landing was also scrapped, due to concerns that the camera might be lost or could injure someone if dropped.

“Then I came up with an idea: how about I roll the camera around the body of the aircraft, to the top, before landing? So you can attach something like a roller-coaster rail around the body of the aircraft, and the camera will go up from the bottom on top to save itself.”

Zaman added that this would not only save the camera in worst-case scenarios, but increase its functionality by allowing for surveillance photography from multiple angles.

This flexible design ultimately netted the team the top prize, as well as additional opportunities from competition sponsors.

The team was invited to present their unique solution to company executives at L3 Wescam’s secure facility, and were each awarded a $300 gift card from sponsor 3D Printing Canada. 

Moving forward, the Avengineers want to bring similar opportunities to U of T for students to showcase their design and engineering skills. “I was so inspired that I decided to make a consulting club at U of T,” said Zaman. “There are a bunch of consulting clubs, [but] they are mostly business consulting clubs. What I am trying to do is to make an engineering design consulting club. Our plan is to ask for problems from different industries and voluntarily, as a student team, solve those problems.”

Plans are also in early development for U of T’s own designathon, to be held next year.

In the meantime, Zaman gave advice for budding designers on the fence about attending competitions: “Even if you don’t have the skills, don’t worry. Just go there. Just participate. You will learn a lot.”

Inside the Myhal Centre for Engineering Innovation & Entrepreneurship

The Myhal Centre will provide students with unique learning and entrepreneurial opportunities

Inside the Myhal Centre for Engineering Innovation & Entrepreneurship

The Myhal Centre for Engineering Innovation & Entrepreneurship exemplifies an architecture that is quiet and understated, so that the focus remains on the activities that will occur within it and not on the building itself.

This was the premise for the Myhal Centre, named after U of T alumni George and Rayla Myhal, which officially launched in May since plans for its construction were first drawn out ten years ago.

Chief architects Robert Davies and Peter Clegg drew inspiration from Canadian-born painter Agnes Martin for the design of the Myhal Centre. Martin’s work drew inspiration from Western and Chinese Classicism, sharing the belief that perfection can only exist in the mind. At first glance, Martin’s paintings aspire to engineering precision, but a closer look reveals freely drawn lines and purposeful imperfections.

In a similar sense, Davies and Chegg designed the Myhal Centre to an idea of engineering precision while encouraging the messy and chaotic activities of human beings.

Most of the spaces in the Myhal Centre are managed by the Faculty of Applied Science & Engineering, while others, like the classrooms and Technology Enhanced Active Learning (TEAL) rooms, are managed by Academic & Campus Events. As such, many courses that will be taught in the new building this fall not only include engineering, math, and computer science, but also archaeology, kinesiology, and earth science.

Aside from its architectural ingenuity, the Myhal Centre is also one of U of T’s most ‘green’ buildings — it has features like cisterns to collect and recycle rainwater, solar panels, and a green roof.

PHOTO by ROBERTA BAKER (Click to Expand)

The Skule Arena on Level 0 was supported by a $1 million donation from the Engineering Society, the undergraduate student government of the Faculty of Applied Science & Engineering. The Skule Arena is an interactive space that will support over 100 clubs and teams U of T Engineering students are a part of. Members of the Human Powered Vehicles Design Team are seen here using the Skule Arena to work on their speedbike.

This level also features a soundproof room, which musical groups and students can use to rehearse, and the Engineering Society Arena, which has garage-style spaces to support clubs and other student activities. Lockers are on this level and other floors for students to store instruments, materials, or projects.



The Skule Arena will support undergraduate teams like the University of Toronto Aerospace Team (UTAT).

From left: Jaden Reimer, Timothy Yeung, Ali Haydaroglu, Mohamed Hirole, Madeline Zhang, Justin Hai, Sandy Fogarassy, David Izatt, and Michael Ding.


A central theme of this facility is that every space is functional and light pours in from every angle. The foyer on the Level 1 of the Myhal Centre is a prime example of this. This is a space where students can study or meet with other students between classes.


The Lee & Margaret Lau Auditorium is a 468-seat technology enhanced auditorium and is the first of its kind in North America. It doesn’t have your typical blackboard, and instead features a wall-to-wall digital array. Instead of rows, this lecture hall has tables to seat six students.The auditorium can be entered from Level 1 or Level 2. As well, a Second Cup is currently being constructed on Level 2.

PHOTO by ROBERTA BAKER (Click to Expand)

Here, U of T Engineering Professor Chirag Variwa is seen teaching a class in a TEAL room. Five TEAL rooms are located on Levels 3 and 4 which have screens on every wall  and movable tables instead of desks. This flexibility is designed to encourage collaboration that isn’t bound by the classroom’s set configuration.

PHOTO by ROBERTA BAKER (Click to Expand)

Level 5 houses various design and fabrication facilities, many of which are open outside of regular classroom hours. Such facilities include the Light Fabrication Facility where students can build parts out of plastic, metal, or wood, and a Prototype Facility that comes with a laser cutter and 3D printers.

From left: students Stephen Dawes, Stephanie McDonald, and Nicholas Chin are seen here creating a prototype in the Myhal Centre for their startup, Hotbox.

PHOTO by ROBERTA BAKER (Click to Expand)

The Norris Walker 5T7 Robotics Lab on Level 5 is an atrium space and will be the new home of the Institute for Robotics & Mechatronics, a cross-disciplinary lab centred on robotics research with applications to real-world problems. Applications of such research include socially assistive robots like those developed from the laboratory of Professor Goldie Nejat, and targeted drug delivery systems like those developed from Professor Eric Diller’s research laboratory.



The atrium on Level 5 is similar to the foyer in that it’s an open space with tables and desks so that students can work between class time.

From left: Chloe Oriotis, Dean of the Faculty of Applied Science & Engineering Cristina Amon, and Sabrina Cupryk.



Launched in 2012, the Entrepreneurship Hatchery is one of the largest and most successful startup accelerators at U of T. The Hatchery helps provide startups access to networking opportunities, space, funding, and equipment. Its new space at the Myhal Centre features large, open spaces to facilitate collaboration. Notable startups include Tejo, Knowtworthy, and Column Mods.



Level 7 is home to the Centre for Global Engineering (CGEN) which enables engineers to solve some of the world’s most pressing issues involving nutrition, sanitation, health, and shelter. One of the centre’s ongoing projects is fortifying foods like tea and salt with iron to prevent and treat anemia. To implement innovative solutions like fortified foods, CGEN partners with organizations and academic institutions around the globe.


The CN Tower and the Art Gallery of Ontario can both be seen from the south view of the Dr. Woo Hon Fai Terrace on the eighth floor. The Terrace is a space for students and faculty from across engineering disciplines to meet and take in the panoramic views of Front Campus and the Toronto skyline. This level is also home to the Institute for Sustainable Energy and the Institute for Water Innovation.

Editor’s Note (September 17): This article has been updated to include a more accurate description of Level 5.

18-year-old U of T student drowns at engineering survey camp

Incident took place at Gull Lake in Minden

18-year-old U of T student drowns at engineering survey camp

An 18-year-old male U of T student has drowned at Gull Lake in Minden during U of T’s Survey Camp for engineering students.

Emergency responders were called to the camp on Deep Bay Road around 4:45 pm. Minden is located about 100 kilometres north of Peterborough.

Sergeant Peter Leon, Central Region media relations coordinator for the Ontario Provincial Police, told The Varsity that so far there is nothing to suggest that the death was suspicious.

“My understanding is the individual who is now deceased was with a group of people in the water. For reasons unknown at this time, he became separated from that group. When they commenced the search for him and located him, they immediately removed him from the water and commenced first aid and CPR.”

Emergency services were called and he was taken to the hospital, where he was pronounced deceased.

According to Leon, the student was from the Mississauga area and his family has been contacted. The victim’s name has not been released.

An investigation into the death is currently being carried out and a postmortem has been ordered by the coroner. 

The death was confirmed by a statement from the U of T Engineering Society and the Civil Engineering Club. 

“All of us process tragedies differently and at different times. Do not hesitate to reach out for support,” read the statement. “We express our condolences to all those who have had the good fortune to know the deceased.”

“Today, our attention must be with those affected by this terrible tragedy,” said Cristina Amon, Dean of the Faculty of Applied Science and Engineering. “The thoughts of our entire community are with the family and friends of the student who died.”

The rest of the week’s programming has been cancelled and the other students returned home Tuesday night.

The survey camp is meant to train Civil and Mineral Engineering students in land surveying and engineering project management. The facility has been in operation since 1920.

If you or someone you know needs help processing this event, you can visit the Health and Wellness Centre at the Koffler Student Services Centre at 214 College St. or over the phone at 416-978-8070.

Editor’s Note (September 5): This article has been updated to include comment from U of T and Haliburton Police.

This story is developing. More to come.

Long-awaited Myhal Centre for Engineering to open at UTSG

Building open to general public, though some spaces to be engineering-exclusive

Long-awaited Myhal Centre for Engineering to open at UTSG

Ten years in the making, the Myhal Centre for Engineering Innovation & Entrepreneurship will be ready for use this year. Development began as early as 2008, with construction starting three years ago.

Full occupancy of the building is expected by June. The site was previously used as a parking lot, and was chosen for development due to its proximity to the Engineering Annex building on St. George Street.

As with all other U of T buildings, the Myhal Centre will be open to the general public. Certain spaces, however, will be restricted to engineering students only

The university hopes the centre will serve as a positive meeting place for innovation. Catherine Riddell, the Executive Director Communications for the Faculty of Applied Science & Engineering, told The Varsity that the university hopes the Myhal Centre “will spark collaboration across disciplines and foster creativity among our students, faculty, staff, alumni and industry partners.”

“As a world-class engineering school, our priority is to provide spaces that enable active, experiential learning and collaborative multidisciplinary research,” Riddell said.

Unfortunately, the building’s history is marred by tragedy. On September 8, 2017, an accident at the site resulted in the death of 52-year-old construction worker Tim DesGrosseilliers. One other worker suffered injuries.

Blue skies and solar cars

Student-run Blue Sky Solar Racing team promotes innovation and sustainability

Blue skies and solar cars

Blue Sky Solar Racing has quickly established itself as one of U of T’s leading design teams. Invested in the design, construction, and racing of solar-powered cars, the club is an incubator for innovation. It has attracted more than 100 members and finished 11th out of 35 teams at the Bridgestone World Solar Challenge in October 2017 with its Polaris car.

The Varsity had a chance to speak with Hubaab Hussain, Managing Director at Blue Sky, about how the team goes from the blueprint to a fully functional, solar-powered car. “Our club takes pride in the ability to not only design, but also build the car by ourselves. We see through the entire build of the car from it’s conceptual design to the time it is on wheels,” said Hussain.

An insider’s look into operations and funding

The club’s annual routine can be segmented into six phases: the learning period, conceptual design, detailed design, building, testing, and racing.

Prior to the construction period, club members identify the particular design and features of the car they hope to build. From there, the team routinely meets every week to review potential ideas for a car design that follows this initial guideline.

According to Hussain, all members are invited to critically evaluate the ongoing design proposals for feasibility and whether one excels in key measures like solar collector performance or total mass. The materials required to build the car, often metal and carbon fibre, are acquired from external vendors.

Hussain explained that assembling the parts to form a fully functional solar-powered vehicle is time-consuming: initial assembly commences in September and extends to the next academic year, with completion expected in June.

Once the car is complete, it is tested extensively in open spaces such as race tracks, air strips, and private lots. Because safety is critically important to the club, there is an active board of certified engineers who examine the car before it’s tested.

Despite extensive planning, the club still faces setbacks. “The most challenging component is sticking to a timeline. A majority of our team members are full time engineering students. During the semester many of the leaders of the team spend a considerable amount of time on this project while managing school as well,” explained Hussain.

In recognition of the club’s continuous accomplishments, Blue Sky Solar Racing receives significant financial support from the Faculty of Applied Science & Engineering and from numerous student bodies and external sponsors. Summed up, the club receives over $300,000 to for the designing and manufacturing of its cars.

Outlook and opportunities

The club’s underlying value of giving students the opportunity to apply their skills outside the classroom is what has driven the team to succeed.

Blue Sky Solar Racing is always on the lookout for exceptional students, irrespective of their stream, to join the engineering, financial, business, IT, or media teams. For interested students, Hussain said to email him or keep an eye out for volunteer opportunities on the Career Learning Network.

“The experience team members get at Blue Sky is incomparable to what they can get elsewhere” said Hussain.