3 November 2023 – Vehicle routing in the real world

Speaker: Ana Sofia Pereira

The vehicle routing problem (VRP) is widely known in the OR literature. Several variants are well-studied but what about the real-world constraints found when actually deploying such algorithms at transportation companies?

Routyn is a VRP solution provider and throughout this session we’ll share some of the constraints found on companies across the world over the past 20 years of real-world experience.

3 NOVEMBER 2023 WEBINAR RECORDING


EURO Practitioners’ Forum past and planned activities are available to the Forum members, as well as the wider public.

Register as a member for free, to get the regular updates on all activities: EPF Member registration page. The recordings and details from previous webinars are also available on our website 

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6 October 2023 – Using Operations Research for good

Speaker: Nicolás García Aramouni, Data Science Associate Manager, Accenture

Operations research and analytics have experienced significant growth in society, but their adoption in developing countries like Argentina has been slower. This is particularly evident in sectors like public schools, where outdated pen-and-paper or spreadsheet methods persist, hindered by low budgets. In Buenos Aires, three schools manually create schedules, a process that can take weeks or months due to multiple factors. However, these schools lack the necessary skills and resources for analytics-based solutions.

This study presents a pro-bono project aimed at helping these schools develop a user-friendly scheduling solution. The project involves constructing a Mixed Integer Programming (MIP) Model that considers teacher availability and subject hours, reducing the schools’ manual work. The model incorporates basic and tailored constraints, addressing the challenge of scheduling teachers across multiple schools. By implementing this solution, the schools achieved record time efficiency in producing schedules for the 2023 year. This project showcases the power of analytics-based solutions and underscores the role of businesses in supporting their communities through pro-bono initiatives.

Abstact

The role of operations research and analytics in our society has been growing in the last few years at an increasing pace. However, in developing countries like Argentina, the adoption of these methodologies has been slower and is currently being led by businesses and universities. In this scenario, some “old-fashioned” sectors still base most of their problem solving on pen-and-paper or spreadsheet software, which makes change management more difficult. This is the case of public schools, a sector which historically has had important infrastructure issues, both from a physical and systems standpoint, generated by low budgets. Under this scenario, teachers usually don’t have high salaries, making them have jobs in multiple schools and partitioning their daily availability in multiple portions that satisfy each institution’s necessities. This generates an interesting challenge when creating the school schedule as teachers do not have exclusivity for the school in question. When talking to three schools in Buenos Aires, Argentina, they told us that currently they do the complete scheduling process manually, which usually takes up multiple weeks or even a whole month at times, which makes sense as they must consider a great number of factors and variables all at once, in addition to completing other tasks, unrelated to this process.

These schools don’t have employees with the skills necessary to help them to create an analytics-based solution that solves this problem. In addition, people with this knowledge are usually skilled workers who usually can get higher salaries working for a technology company, making the situation more difficult for the budget-constrained schools. Therefore, businesses should have a more active role in society, helping their community and sharing their specific knowledge through pro-bono activities.

The idea of this pro-bono project is just that: helping three schools in Buenos Aires create a schedule in a user-friendly way. To achieve this, we created a solution that had two very important objectives:

1) Build a Mixed Integer Programming (MIP) Model that generated a valid schedule considering the availability of each teacher, how many hours a subject needs, etc.

2) Change and reduce the manual work done by schools In this sense, our aim was to change the work made by these schools to create the schedule: instead of having to create the whole schedule, they would only need to manually create the inputs needed by the model. We asked them to create two inputs: one would

indicate how many hours each subject needs to be taught at each course, and who is the teacher of that course. The other one should reflect the availability of each teacher. These inputs were fed into our MIP model, which incorporated both basic constraints (a teacher cannot teach two different subjects simultaneously) and tailored constraints (for example, certain subjects couldn’t be taught when students just got to school at 8 AM). Considering that multiple teachers were employees of the three schools, we couldn’t partition the problem, generating the challenge of building a model that could generate the schedule for all.

Here, there is no revenue metric that we are trying to optimize. However, what we did was improve productivity as this model let these schools produce their schedules for the 2023 year in record time, as they only needed to invest a couple of days to generate these inputs and let us know the conditions and constraints that the final schedule should follow. As an additional result, we showed the power of analytics-based solutions and were able to share this with our local community.


EURO Practitioners’ Forum past and planned activities are available to the Forum members, as well as the wider public.

Visit the website and register as a member for free, to get the regular updates on all activities: EPF Member registration page. The recordings and details from previous webinars are also available on this website.

Follow the Forum on Twitter and LinkedIN , and feel free to get in touch.

8 September 2023 – Improving quality of OR data sets

Presented by Dr. Inci Yüksel-Ergün, Zuse Institute Berlin (ZIB)

Data is ubiquitous in the age of analytics. The reliability of decisions based on OR studies depends on the underlying data quality. However, identifying pertinent data and assessing its quality is challenging. It is inevitable to employ highly-connected and consistent real-world data sets to model complex decisions. When expert knowledge becomes obsolete with disruptive changes, we require more complex models to comprehend the impacts of these changes.

When conducting projects with industry using highly connected data, we encountered several cases where our analysis detected data errors that were too complex for humans to understand. Examples for our analysis include irreducible infeasible subsystems (IIS) of large mixed-integer programs (MIP) and bottlenecks in highly nonlinear networks. While detecting such errors is a significant achievement, removing them is extremely difficult.

In this presentation, we highlight our insights on data quality improvement. We report our results on data from the German high-pressure gas transport network using methods from data preprocessing and mathematical optimization.


EURO Practitioners’ Forum past and planned activities are available to the Forum members, as well as the wider public.

Visit the website and register as a member for free, to get the regular updates on all activities: EPF Member registration page. The recordings and details from previous webinars are also available on this website.

Follow the Forum on Twitter and LinkedIN , and feel free to get in touch.

7 July 2023 – Using Operational Research to improve Aviation Security

Presented by Tom Occleston, MSci(Hons) CSci, Business Consultant, Atkins

Operational Research is the science of better decision making. Aviation is a complex industry where existing and emerging threats need to be considered carefully when balancing the need for improved safety with the need to maximise passenger throughput, minimise the space taken up by security measures, and minimise unnecessary costs. How can we, as Operational Researchers, help the aviation industry to design ‘optimal’ security solutions?

7 JULY 2023 WEBINAR RECORDING

2 June 2023 – Blending hydrogen in the German gas network with unprecedented flow patterns

Presented by Jaap Pedersen, Zuse Institute Berlin

The European gas infrastructure is being disruptively transformed into a future decarbonized energy system, a process that needs to be accelerated, given the current political and economic situation. On the one hand, there is a growing hydrogen market; thus, pipeline-based transport using the existing natural gas infrastructure becomes economically viable. Further, using existing infrastructure helps to increase public acceptance and accelerates the transition process. On the other hand, due to Russia’s aggressive invasion of Ukraine, gas supply and transportation have changed significantly in Europe and particularly in Germany by moving sources of supply from east to west in 2022.

In this talk, the maximum technically feasible feed-in of hydrogen into the existing German natural gas transport network is analyzed with respect to regulatory limits of gas quality. The basis is a transient tracking model that builds on the general pooling problem including linepack. We investigate the impact of the new supply situation on the hydrogen distribution by comparing historical gas flow data from 2020/21 to more recent data from 2022. It is shown that even with strict limits, the gas grid offers sufficient capacity to serve as a guaranteed customer for a large part of the green hydrogen generation capacity planned until 2030 for both periods. A higher hydrogen feed-in is possible in the current gas supply scenario, as the provided gas quality is higher, and existing and potential locations of hydrogen production are more likely to be found in the northwest of the network. With our presented method, it is possible to evaluate unexpected situations in the gas networks quickly and increase the system’s resilience.

17 May 2023 – Applying Systems Thinking to Social-Ecological Issues for UK Government

Presented by Dr. Gary Preece, Head of the Systems Research Programme, Department for Environment, Food and Rural Affairs (Defra)

Dr. Gary Preece is Head of the Systems Research Programme in the UK Government’s Department for Environment, Food and Rural Affairs (Defra). He is also an analyst in the Government Operational Research Service with experience working for a range of government departments in the UK and abroad. Prior to working in government, Gary worked in academia researching systems thinking approaches to support information management and disaster response. Gary holds a PhD in systems thinking from Aston Business School and is a Fellow of the Operational Research Society.

Biodiversity loss and climate change continue to raise the stakes for environmental, agricultural and food policy across the globe. Issues in these policy areas can cascade across countries and across different sectors of the economy. The social-ecological systems within the policy remit of the UK Government’s Department for Environment, Food and Rural Affairs (Defra) often behave in ways that are complex and unpredictable. The policy challenges can be wicked and intractable, with potential solutions contested by actors with conflicting goals.

Systems thinking can help us understand complex issues by encouraging us to examine inter-relationships and account for wider factors, perspectives and influences within the problem-solving process. The Systems Research Programme at Defra has been running since 2019, providing a dedicated team to support Defra undertake systems thinking analysis to tackle some of its most complex and intractable issues. In this talk, I will introduce Defra’s approach to systems thinking analysis, highlight different techniques used and provide reflections on how systems thinking can be used to support policy and decision making in complex areas.

14 April 2023 – Optimizing Manufacturing Scheduling for Injection and Paint Lines in Automotive Production: Insights from a Top Supplier

Presented by Issam Mazhoud, PhD, Solution Architect, DecisionBrain

In this talk, we draw lessons from a leading automotive supplier who adapted its manufacturing scheduling approaches to leverage optimization to effectively schedule and synchronize its injection and paint lines. The supplier’s production model involves a combination of make-to-order and just-in-time to fulfill the needs of its automotive customers. Using optimization techniques has led to improved service level and capacity usage. The presentation will concentrate on the challenges faced, as well as the methods and approaches used to address them.

14 APRIL 2023 WEBINAR RECORDING

14 APRIL 2023 WEBINAR PRESENTATION

10 March 2023 – Bandits for Online Calibration: Application to Content Moderation at Meta

Presented by Deeksha Sinha, Research Scientist at Meta

What tech lies behind the social media giants’ attempts to keep content ”within the rules”? At Meta, we have both hand-crafted and learned risk models to flag questionable content, for humans to review. To operationalize these, we aggregate the different models to give a single ranking score, calibrating them to prioritize more reliable risk models. But violation trends change over time, affecting which risk models are most reliable; risk models change; and novel models are introduced. To continuously update the system in response to such trends, we use a contextual bandit. Our approach increases Meta’s top-line metric for measuring the effectiveness of its content moderation strategy by 13%.


13 January 2023 – What if we could turn our AI/OR algorithms into full web apps in no time

Presented by Vincent Gosselin (Co-founder, Taipy)

In the Python open-source eco-system, many packages are available that cater to:

– the building of great algorithms

– the visualization of data

– back-end functions

Despite this, over 85% of Data Science Pilots remain pilots and do not make it to the production stage.

In this tutorial talk, we will demonstrate the usage of the Taipy, a new open-source offering we developed. With Taipy, Data Scientists will be able to build great pilots as well as stunning production-ready applications for end-users.

Taipy provides two independent modules: Taipy GUI and Taipy Core.

1. Taipy-GUI goes way beyond the capabilities of the standard graphical stack.

2. Taipy Core provides a simple yet very powerful execution framework for Optimization execution pipelines.

We hope that this contribution will support an easier and faster adoption of the data science and operations research solutions by end users.

13 JANUARY 2023 WEBINAR RECORDING

13 JANUARY 2023 WEBINAR PRESENTATION

2 December 2022 – Analytics Transformation in a year – mission possible

Presented by Ramunė Šabanienė, Data Strategy Director (Telia Finland)

Telia, as many large organisations faced continuous struggle with keeping up to date analytics infrastructure through mergers and acquisitions, as well as adopting data structures in line with ever increasing speed of changes in business. Having joined Telia Lithuania to lead the transformation, I will talk through the timeline, inputs used to draw strategy, re-thinking the talent management in light of better support of digitisation initiatives and finally – what it takes to execute Analytics Transformation in short timeline.

2 DECEMBER 2022 WEBINAR RECORDING