Maths-Enterprises Study Group (MESG) in Strasbourg

The Maths-Enterprises Study Group (MESG) in France aims to create exchanges between companies and math junior researchers through a week of work on industrial problems requiring innovative mathematical approaches. There is a MESG every three to five months in France. These events are sponsored by the Agency for Mathematics in Interaction with Enterprises and Society (AMIES)

Anatomy of a MESG

A MESG took place in Strasbourg organized by Cemosis a few weeks ago(Nov 12-Nov 16 2018). Six enterprises presented open issues on the first day, not necessarily formalized, which constitute an obstacle to their business, a lock that mathematicians can help unlock. Tuesday to Thursday, small groups of researchers work on these issues and explore different approaches. Each group is supervised by more experienced researchers, but retain complete freedom as to the direction of its work. Friday is devoted to the presentation of the explored paths in front of the industrialists. We encourage all Ph.D. students, postdoctoral fellows, to participate in this week, regardless of their specialty, whether theoretical or applied, whether their profile matches or not the subjects offered.

Topics at the MESG

So we had six enterprises proposing challenges and we had about 22 Ph.D. students and postdocs registered to this event.

Électricité de France(EDF) : Mixtures of gases to build complex equations of state

EDF needs reliable numerical studies of flows to reinforce the safety demonstration of its nuclear production plants. To simulate hypothetical accidents, numerical codes require models able to describe complex physical situations and strongly unsteady phenomenon: a classical example is the loss of coolant accident, in which a breach in the primary pipe is assumed. The reactor water, pressurized at 150 bar, is suddenly put in contact with air at atmospheric pressure, leading to a very sudden water vaporization. In such situations as in many others, temperature and pressure vary a lot and can possibly reach domains which are difficult to describe with a simple equation of state, like the neighborhood of the critical point for instance.

Current works consist in improving the physical description of the water behavior in the models. Indeed, a classical possibility is to describe the water behavior with a simple equation of state, as the stiffened gas equation. Physically, this law is close to a perfect gas equation, which is modified to take into account the particular behavior of a liquid. This law is defined using a reference point, where all the physical quantities are known (pressure, temperature, enthalpy, thermal capacity…). Near this reference point, the equation of state is realistic, but its accuracy decreases when pressure and temperature are too far from the reference point.

Finally, a stiffened gas equation correctly describes a limited domain in the thermodynamical plane. This domain is too limited for the accidental scenarios which might hypothetically occur in a pressurized-water reactor. Our idea is the following: a complex equation of state, more realistic on a wider physical area, could be built as a mixture of several simple equations of state. The starting point is to consider two stiffened gases. Each one is defined using its own reference point, and they are thuand s accurate on different domains in the thermodynamical plane. The aim is to then build a mixture of this two laws which fulfills the following constraints: (i) The mixture law does not decrease the accuracy near the reference point of each stiffened gas, (ii) The mixture law is accurate on a wider area than the gathering of accuracy area of each stiffened gas law and (iii) Some mathematical constraints are needed for our model (convexity constraints…)


Electis: Mathematics in the supply chain

Electis is a distribution company in electronic and energy equipment. It is the link between manufacturers (ex: Legrand, Hager, Schneider, etc …) and professional customers (installers electricians, industrial, administrations, etc …). A distributor deals with logistics, storage, after-sales service, and other services. For the good functioning of the company, the company must make profits between the purchase of the equipment at the manufacturers and the sale of the equipment to the customers. For Electis, the clientele consists exclusively of professionals. In this context, we encounter several difficulties (i) Competitor prices are unknown, there is no “reference price” or market price for these products(except for a public price) (ii) the customer typology is heterogeneous from the small craftsman to very large groups.

As part of the MESG, it is proposed to model a distributor’s business and strategic environment, as well as interactions with competing manufacturers, customers, and distributors based on a reduced set of dummy data generated by true data. It is a question of studying if the modeling makes it possible to find the interactions of negotiations in the lines of sale. We can think of different types of mathematics to deal with the problem: (i) game theory, (ii) hidden state Markov models, or (iii) multi-agent modeling.

The goal of the MESG on this subject is to provide some ideas for modeling and algorithms to deal with the subject. Electis is particularly interested in (i) establishing a state of the art on the basis of preliminary work on mathematical modeling of the negotiation and the related algorithms and (ii) exploring one of the possible paths of negotiation modeling through data. Available.

Fives: static and dynamic study of stacking

Fives, an industrial engineering Group, designs and supplies machines, process equipment and production lines for the world’s largest industrial groups including the aluminum, steel, glass, automotive, aerospace, logistics, cement, and energy sectors.

In the context of certain production flows, the Fives company has to transport a maximum number of parts during a minimum of journeys. From parallelepiped-shaped wooden panels with provisions in a stock, the objective is to build the most stable stackings possible.

The means and models of stacking are multiple and we currently use our feedback, as well as an empirical method of stack stability.

The topic of the SEME is, therefore, to propose methods to determine the rules of stacks according to the following elements:

  • characteristics of the parts to stack
  • the characteristics of external elements (stacking support, transport system …)

The objective is to determine the most important factors for this problem as well as their impact on the creation of stacks.

Keeseek : one job one home

Keeseek, a startup company, develops an online platform that provides
a unique recommendation setting: from personal data stored by Keeseek, possibly including text (i.e. CV, statement of purpose), maybe some historical data for the user; the platform provides a job offer from a list of job offers in a database in a given geographical area with potential interest for the user and
for which the candidate must be skilled enough. The platform matches the job offer with lodging offers and facilitates the renting process.

The main issues are text data mining such as information retrieval and find out whether an individual will be able to tackle a job using both explicit or indirect (latent) data.

Autonomous Port of Strasbourg: Optimising storage areas

The Autonomous Port of Strasbourg(PAS) is the 2nd largest river port in France and the 4th Rhine port. His three missions are:management of the industrial-port area of 1,000 ha – maintenance of transport infrastructure (fluvial, rail and road) and management of the business area with 320 companies and 10,000 employees via its subsidiary Rhine Europe Terminals: operation of the Strasbourg and Lauterbourg container terminals via its subsidiary Batorama: passenger transport with boats promenade. In 2017, the PAS Group has adopted a new strategy for the next 10 years that focuses on two major ambitions: being an economic and port actor of reference, an exemplary actor in his practices and actions.
5 objectives must make it possible to reach this milestone:  (i) Develop the attractiveness of port areas (ii) Develop multimodal traffic
Increase performance (iii) Reinforce the integration / the place of the port areas in their environment (iv) Being an innovative and responsible actor both internally and in its external actions
The Topic of the MESG is as follows: the southern container terminal of the PAS faces saturation problems related to an increase in container traffic. To streamline these traffics, the terminal will be expanded in 2019 on adjacent land. This enlargement is an opportunity to rethink its organization and functioning. The objective of the SAP is to define the optimal organization of the terminal, particularly with regard to the storage locations, on the extended field using data from the terminal management system and the site plan.As such, the PAS proposes a challenge to develop a tool to simulate the organization of storage areas in relation to loading/unloading areas and the location of river portals in order to optimize movements. (planning simulation tool)

Rayce-Araymond: Image Search, Match the Fasteners

Rayce is the ARaymond Network Center of Expertise. When an ARaymond Network company identifies a new opportunity or wants to improve a product or process that is beyond their expertise, the project is handed over to Rayce, where the innovation process begins – creating or adding value to materials, technology or an integration process. Araymond is an International expert in fastening and assembly solutions, the ARaymond Network imagines, designs and produces clipping systems, fluid connection, and bonding solutions.

In the context of the MESG, we consider an assembly situation (male-female parts interaction). from a real “female” part, by using photo search innovative technologies, we would like to propose a selection of matching “male” parts contained in the products catalog. Real and virtual assembly parts such as photos from the product catalog of Araymond and possibly 3D models will be provided. To start, typical male parts are a selection of clips and female parts are plates with holes that can receive the clip.

Next Steps after the MESG

The feedback from both the students and enterprises was very positive: the enterprises were surprised by some of the solutions proposed and sometimes the performances achieved by the algorithms. As to the Ph.D. and Postdocs, they enjoyed the short but intense format of the MESG, the variety of mathematical topics and the team spirit.

Each group is preparing a report on the work done. In the following months, these reports will be made ​​available on the open archive  the HAL repository.