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90th European Study Group
Mathematics with Industry
Leiden, 28 January - 1 February 2013

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Problems considered by previous Study Groups and results on these can be found here.
The Study Group 2013 will consider the following problems, in arbitrary order
(other problems are under consideration or can be sugested still, see below):
Coffee market volatility
Returnable Packaging Materials in markets
Stress fields inside a neck
Oxygen transport in germinating seeds
Fundamental problems of spatial reuse in wireless networks
Effective water storage: Rijnstrangen

Descriptions of problems:
Coffee market volatility
Nedcoffee B.V.
Coffee is a tropical product, produced in over 50 developing countries. It is the second most traded commodity in the world. Coffee makes an important contribution to socio-economic development and poverty alleviation and is of exceptional importance to exporting contries, some of which rely on coffee for over half their export earnings.
The coffee market can be very volatile even over short periods of time.

Nedcoffee is looking for better ways to access and model market volatility and Value-at-Risk of their portfolio. Historical market data (coffee and option prices) will be made available.
Nedcoffee is a major coffee trader with headquarters located in Amsterdam, from which green coffee from its sourcing companies in Africa and Asia is traded and controlled.
>> detailed description [pdf]
Returnable Packaging Materials in markets Heineken
Heineken owns a vast amount of Returnable Packaging Materials (RPM: bottles, crates and kegs) worldwide. The company expects to increase the investment in RPMs significantly in the coming years. Their use has a great financial impact in the needed investments and, depending on the returnable system, on the Profit and Loss of the company.

Task for the study group is to develop a (statistical) model for estimating the amount of RPM items in the different markets Heineken operates in.

Heineken Global Logistics is Heineken's international supply chain knowledge centre, located in Zoeterwoude, the Netherlands. One of the knowledge areas is the management of RPM.
>> detailed description [pdf]
Stress fields inside a neck
If a material, e.g. a metal, is stretched it can reach a point where all of the strain is concentrated in just one area. Such a condition is called necking, see photo.
Within the neck, the state of stress becomes fully 3-D and can no longer be represented by the state of stress in the surrounding material. The accurate but simple modeling  necking
of this phenomenon is important for example for the simulation of collisions.

The goal of this project will be to use the insight into the 3-D state of stress inside of a neck to simplify Bai and Wierzbicki's 3-D failure locus into a 2-D one that accounts for the state of stress inside of the neck better than the current ones.

>> detailed description [pdf]
Oxygen transport in germinating seeds
Fytagoras logo
Seed germination in most seeds depends on the availability of oxygen. Living seeds start respiration upon imbibition and respiration accelates at the moment the germination really commences. Single seed oxygen consumption can be measure e.g. with a Q2 machine, at a detailed time resolution. The interpretation of the data in terms of physical, morphological and physiological properties of and processes within the seed is still hard. It also hampers advances in seed treatment possibilities.

The problem consists of the development of a mathematical model  for the oxygen transport and consumption in a seed that fits to the current biological knowledge and detailed single seed oxygen consumption measurements. Samples of the latter will be made available.

Fytagoras is a dynamic innovative company oriented at science with much expertise in fields of sensor technology, seed technology and plant breeding.
>> detailed description [pdf]

Fundamental problems of spatial reuse in wireless networks
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The proposed problem and its more complex variants touch upon fundamental problems in resuse of wireless networks. For example, they relate to the performance of distributed, stochastic gossiping algorithms, as used for maintenance and update of network information. In the problem discs of fixed radius are thrown onto an area such that the center point is located at a grid point that is drawn randomly from those that are still not covered.

The question is, how many discs need to be thrown onto the area until each grid point is covered, or more challenging, what is the distribution for the number of throws required.

Philips Research is a global organization that helps Philips introduce meaningful innovations that improve people's lives.
>> detailed description [pdf]
Effective water storage: Rijnstrangen
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The Dutch dikes have been constructed such that they can deal with exceptional water levels that occur once in 1250 year. In the last couple of years this extreme water flow was increased from 15.000 m3/s to 16.000 m3/s. In order to cope with this increase it was decided to provide a larger flow bed for the rivers, instead of raising the dike levels. The area called 'Rijnstrangen', where the Rhine enters the Netherlands from Germany, is considered for the realisation of such an extended flow bed. Water should enter this region only when the water flow is above a given threshold level.

The main questions (among others) is how to construct a water barrier that leads to such an inflow, how many are needed and where to locate these, to get an optimal result.

'Rijkswaterstaat' is the executive body of the Dutch Ministry of Infrastructure and Environment.
>> detailed description (in Dutch) [pdf]

Suggestions for problems
Problems may come from a wide variety of subject areas, but should be amenable to mathematical modelling and analysis. Almost all industrial problems have some mathematical aspect to them, although the mathematics is not always recognisable at first. Indeed, from our own experience, some of the most successful study group problems have not been well-defined in mathematical terminology at the start of the study group.

Some ideas developed during the Study Group may require more time than one week to elaborate on. These may lead to more research after the study group itself, for which useful contacts are made between researchers in industry and at the universities to work together if needed. The meeting helps to further establish links between industry and academia and in particular to encourage the greater use of mathematical modelling in industry.

All interested  are invited to contact the organising committee.
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