VDL ETG – Droplet on Wafer

VDL Enabling Technologies Group is part of VDL Groep, an international industrial family-owned company with 97 subsidiaries, spread over 20 countries, and more than 17,000 employees. It is a conglomerate of flexible, independent companies, each with its own specialty. The strength of VDL Groep lies in the mutual cooperation between the companies. VDL Enabling TechnologiesView problem details

SWECO – Event Driven Model with an Objective to Control Traffic Lights

SWECO designs and develops societies and cities of the future. This consulting company advises in sustainable buildings, efficient infrastructure, and access to electricity and clean water. SWECO is the largest engineering and consultancy company in Europe, with over 15.000 employees. The Mobility Solutions team of SWECO actively works on optimizing traffic flows in today’s cities,View problem details

Sweco Traffic Lights

KNLTB – A Model for Optimal Rating in Tennis Matches

KNLTB KNLTB is the Royal Dutch Lawn Tennis Association. The main goal of KNLTB is to support as many people as possible – of all ages and (dis-)abilities – to play tennis and make sure they keep playing. We represent 560.000 tennis members associated with approximately 1650 local clubs. KNLTB coordinates the annual match calendar,View problem details

Vanderlande – Optimizing Warehouse Operations

Vanderlande is the global market leader for value-added logistic process automation at airports, and in the parcel market. The company is also a leading supplier of process automation solutions for warehouses. More than 45 million parcels are sorted by its systems every day, which have been installed for the world’s leading parcel companies. In addition,View problem details

ShoQR – Building a Mathematical Model to Estimate Joint Loading and Predict Joint Tissue Damage

We train physiotherapists in treating patients with knee osteoarthritis (degenerated, damaged cartilage). Overload of joints should be avoided, especially the repetitive impact on the affected leg, as this is related to cartilage degeneration. Three-dimensional motion analysis allows us to measure joint load with high precision but is very expensive. Together with physiotherapists and universities, weView problem details

PostNL – Model for Optimal Connection Between Customer and Sorting Center

Apart from mail delivery, PostNL’s most important service is to transport parcels ordered at webshops (PostNL’s customers) to consumers. This service is provided at an enormous speed and accuracy (99% within 24 hours) and at incredibly high volumes (parcels per day). As a consequence, highly efficient business processes are required to maintain this service inView problem details

KWR – Predicting the Removal Performance of Activated Carbon Filters in Water Treatment

In the Netherlands, about one-third of the drinking water is produced out of surface water that may contain all kinds of micropollutants (pesticides, pharmaceuticals, industrial compounds). A large fraction of these drinking water production sites uses filtration by sorption onto activated carbon as an important barrier for micropollutants that are present in the water. TheView problem details

Synopsys – Latency Prediction for On-chip Communication

When placing components on a chip one is faced with several objectives. A major objective is that the length of the connections between the components should be minimal. For this aspect heuristic algorithms are available. Another objective is that the envisioned clock frequency can be met, or at least have the smallest violation. This frequency isView problem details

MARIN – The Numerical Towing Tank

The Maritime Research Institute Netherlands (MARIN) has been expanding the boundaries of maritime understanding of hydrodynamic research for over eighty years. MARIN has a dual mission: to provide the industry with innovative design solutions and to carry out advanced research for the benefit of the entire maritime sector. Starting in the 1930s, one of ourView problem details

SWECO – Controlling Traffic in the City of the Future

SWECO designs and develops societies and cities of the future. This consulting company advises in sustainable buildings, efficient infrastructure, and access to electricity and clean water. SWECO is the largest engineering and consultancy company in Europe, with over 15,000 employees. The Mobility Solutions team of SWECO actively works on optimizing traffic flows in today’s cities,View problem details

Bruil – Prediction of Print Success for Concrete 3D Printing

Bruil Beton & mix is specialized in the production of concrete for all kinds of applications. In the past years, Bruil has developed a new, exciting technique that has revolutionized this sector: the production of prefab elements using concrete 3D printing. This development offers architects a completely new scale of design possibilities in form, color,View problem details

Bruil - 3D printing

Hendrix Genetics – Turkey Body Weight Prediction

Hendrix Genetics is a Dutch multi-species animal breeding, genetics, and technology company and one of the world’s leading breeders and distributors of turkeys. An important characteristic of turkey breeding is body weight. In a recent trial, approximately 200 turkeys were walked individually through a corridor in which a force plate was placed. During each walk,View problem details

Turkey Body Weight Prediction

DNV GL – Stability Analysis of a Buck Converter in Feedback Control

DNV GL in brief DNV GL is a global quality assurance and risk management company. Driven by our purpose of safeguarding life, property, and the environment, we enable our customers to advance the safety and sustainability of their business. We provide classification, technical assurance, software, and independent expert advisory services to the maritime, oil &View problem details

Hobaho – Optimal Use of in Vitro Techniques in Dutch Bulb Industry

Introduction Dümmen Orange represents a legacy of floricultural excellence for more than a century in the making, providing the largest selection of superior flowers and plants on earth. Recently, Dümmen Orange acquired companies specialized in flowers from bulbs and tubers. The Dutch bulb industry distinguishes itself from the rest of the flower industry in thatView problem details

SciSports – Player Evaluation in Soccer Using 2D Tracking Data

Company Introduction SciSports is a spin-off from the University of Twente, founded by Giels Brouwer and Anatoliy Babic in 2012. SciSports is a company which focusses on applying Scientic Methods in the world of soccer. Currently our focus is on the application of data analytics in soccer. Currently we have offices in Enschede and Amersfoort,View problem details

CBS – Causal Effects of Government Decisions on Earthquakes in Groningen

CBS (Statistics Netherlands) is the national statistical agency of the Netherlands, responsible for all official statistics of and about the country. In recent years the activity of Statistics Netherlands has expanded to provide more in-depth technical analyses of all data that it collects and archives. The demand for such technical analyses has increased because allView problem details

CQM – Optimal Order Picking from a Large Retailer Warehouse

The situation is as follows: A conventional retail warehouse handles customer orders. A customer order is picked into different totes. The totes are picked by order pickers. For efficiency reasons, an order picker picks a set of totes. This set is called a batch. Products are stored in racks divided over multiple aisles. Ideally, aView problem details

SKF – Weibull Estimation of Bearing Performance from Acceptance Tests

  SKF is the world-leading supplier of products and solutions in the rolling bearing business. Bearing performance is assessed via intensive life testing and physical modeling. Beyond that, customers may require specific acceptance tests in the specific operating conditions from their application. Acceptance tests are usually dealing with a limited sample size meant to surviveView problem details

MARIN – Quiescent Periods for Helicopter Landing on Ships

Helicopter landing operations on ships are dominated by the expectation that ship motions will stay inside operational limits for a given time. For naval ships, the main criterium is the touchdown conditions. The minimal duration of an operational window is expressed in tens of seconds. The assessment of this expectation is done by the landingView problem details

ABN Amro – The Fair Value of a Mortgage

ABN AMRO is a retail bank and mortgages are an important part of the core business model. The balance sheet covers over 150 billion euros in residential mortgages, which is about 40% of the total assets. In order to properly steer the balance sheet and manage the bank’s risks, it is essential to correctly estimateView problem details

ABN - Fair value of a mortgage

TNO – Analyzing and Predicting Impact Created by Accidents on Road Networks

Road networks are becoming more and more vulnerable to incidents as a result of an increasing level of congestion. Predicting ‘reliably’ the expected time of arrival (ETA) is therefore becoming a serious challenge as incidents/accidents occurrence is quite a random process and their impact depends on a variety of factors making it far from trivialView problem details

Shell – Numerical-physical Modeling of Miscible Fluids in Pipeline Transport

In the oil and gas industry hydrocarbons are transported through long pipelines under various conditions. This transport process generally involves multiple chemical components present in multiple phases (oil, gas, water). The mathematical modeling and simulation of these problems is often done with one-dimensional models that treat the phases as immiscible. However, a particular case thatView problem details

Ericsson – Route Information from a Central Route Planner

We present a discussion of a problem posed by researchers of the company Ericsson, namely, to estimate the fraction of the road users in a road network that must participate in a central route planning scheme such that travel time predictions improve significantly. A road user who participates is expected to inform the central routeView problem details

Schlumberger – Displacement of a Viscoplastic Fluid in an Inclined Slot

The steady displacement of one viscoplastic fluid by another is studied in an inclined channel. The aim is a prediction of the finger width from simple balance laws. It is argued that no accurate prediction can be acquired from the far-field velocity profiles only, but that instead a calculation of the two-dimensional behavior near theView problem details

KPN Research – Cache as Ca$h Can

In this contribution, several caching strategies for the World Wide Web are studied. Special attention is paid to the so-called proxy placement, i.e. placing of caches on carefully selected nodes in the network near to the end-users. Using both a deterministic and a stochastic approach, algorithms are developed for calculating the allocation and sizes ofView problem details

NLR – Wind Tunnel Model Position and Orientation

In this contribution, the determination of the position of moving and deforming objects in wind tunnels from CCD camera information is studied. An analytical approach is discussed which solves the problem directly from manipulating nonlinear distance formulae. Also, a least-squares approach is given, which is most convenient to implement from a numerical point of view.

Trespa International – Modelling of moisture induced warp in panels containing wood fibres

In this contribution the deformation of panels, used a.o. in furniture, is discussed in relation to the moisture content. It is shown how the variations in temperature, water and resin concentrations during the pressing process of the panels can be modelled. The panel deformation is modelled using linear elasticity theory. An explicit analytical expression forView problem details

Philips NatLab – On Compact Models for High-voltage MOS Devices

Fast evaluation of integrated circuits(ICs) requires the availability of so-called compact models, i.e. simple-to-evaluate relations between the voltages and the currents in the IC-components. In this paper, the compact model for a particular IC-part, the LMDOS device, is studied. This model consists of coupled submodels, each of which describes a separate part of the LDMOSView problem details

Akzo Nobel – Color Matching

We consider the problem of creating paint of a certain target color by mixing colorants. Although a large number of colorants is available, in practice it is only allowed to use a limited number. We focus on the problem of selecting the right subset of colorants.

Oude Kerk Delft – The Bourdon Bell and the Skewed Tower

The first parish church of Delft, the old church, was built around 1200. In front of the church a 75 meters high tower, with a brickwork spire and four turrets, was built in 1350. Even during its construction, the tower was plagued by subsidence. This could be because the water in the Oude Delft hadView problem details

Demis – Zoning Problem in Determining Environmental Impacts of Traffic

Introduction Traffic has an impact on the environment. Traffic models are normally used to calculate the traffic intensities on the road network. The calculated traffic intensities form the basis for calculating environmental impacts. In the impact assessment, the traffic intensities are converted to the width of the zone that has negative impacts on the traffic.View problem details

X-flow – Leakage Detection Method

For the purification of water hollow fiber membranes are increasingly being used. These are porous reeds with a diameter of between 1 to 2 mm, made by a particular type of plastic. The ‘wall’ of these reeds has a fine porous structure that is permeable for water, but not for particles of certain sizes. TheView problem details

AOT – ADR Option Trading

Problem The problem AOT presents is that of ADR-option pricing. In the brief outline below the problem and its setting are described. In the final presentation of the problem, a brief introduction to options and option pricing will be given, such that the jargon will be clear. ADRs As a stock and derivative trading firm,View problem details

Rekenkamer – Is there a Financial Life After an Error?

In many cases, accountants make their judgment on a financial report based on samples taking at random. An approval is issued when the data in the report satisfies a given reliability interval (often reliability of 95% is used), i.e., the errors found in the samples is not exceeding a certain critical value. In reality, quiteView problem details

Twaron – The Rotor Spinning Process for Fibre Production

At Teijin Twaron in Arnhem new ways of producing fibres are being developed. One of the interesting new techniques is “The Rotor Spinning Process”. In principle, this process looks a lot like the making of sugar floss (or cotton candy) at the carnival/fair. Here, however, we deal with a polymer-filled disc with tiny holes. TheView problem details

NOZ – Reconstruction of Sea-surface Temperatures Using Fossil Marine Plankton

The predictive quality of climate models can be enhanced by incorporating information about temperatures from the past. A number of methods have been developed to determine the ancient temperatures of the upper ocean, and one of these is based on the use of deep-sea microfossils. For many millions of years, a large number of speciesView problem details

Phytocare – Parameters to Grow Roses

In agriculture, the key point is optimizing the production at limited costs. For decennia already, one has tried for the best and one cannot do without a computer anymore. In present-day greenhouses, the control of the inner climate is fully automated. The inner climate could be held constant, but for the optimization of the production,View problem details

Artis – Aquarium Problem

The Artis Zoo has a problem in its Aquarium and in the adjacent Zoological Museum. Situation Part of the Aquarium is a corridor that contains so-called mammoth tanks which measure 5 by 2.5 by 20 meters and are filled with water. Because of the tropical fish inside, the water should have a temperature of 24View problem details

Philips – Compression of Data

Philips Natlab is looking for new ways to compress audio-signals. Situation A new method for the digital representation of high-quality audio signals has been introduced as an alternative to the widely used 16-bit recording format used for CD signals. This new method [3] produces 1-bit samples at a rate that typically is 64 times higherView problem details

Magma – Design Automation: Component Placement on Chips

The ‘holey cheese’ problem One of the steps in the design process of chips is the positioning of every single component or ‘cell’ on the chip. The cells are mutually connected by wires. The wiring scheme is given, and in this phase of the design process, the positioning of the various cells must be determined.View problem details

Eurodiffusie – Diffusion of Euro Coins over Europe

From 1st January 2002, we have the unique possibility to follow the spread of national euro coins over the different European countries. We model and analyze this movement and estimate the time it will take before on average half the coins in our wallet will be foreign.

Akzo Nobel – Instability in the Spinning of Fibers

A well-known problem in the spinning of fibers by drawing a liquid through a spin hole is that when the speed is increased, there appears an instability in the sense that the cross-section of the filament is no longer independent of time. In fact, oscillations arise at a large speed of spinning. In 1969 MatovichView problem details

Dr Daniel den Hoed Kliniek – Pattern Recognition in CT Scans

When making a diagnosis using a CT scan one looks for spherical shapes amidst bones and lung tissue. Where the bones show a value of 1000 on the CT san and air and lung tissue are at 0, the spheres distinguish themselves at a value of around 150. For the automatic pattern recognition one canView problem details

Eldim – Laser Percussion Drilling

Laser materials processing is well accepted in the industry. Most important applications are cutting, welding and marking. Drilling is a niche application. Only 2% of the system sold is used for drilling. In the gas turbine manufacturing, laser percussion drilling is used to drill film cooling holes. The typical hole diameter is 0.5 to 1.0View problem details

KPN – ADSL Modems

The Transmission Control Protocol (TCP) is a well-used protocol to send information files over the Internet. The essence of this protocol is that the total quantity of information is divided into a number of smaller packages. Sending the data error-free is made possible by detecting the packages in which an error has occurred and resendingView problem details

NMi Van Swinden Laboratorium – The T-factor for a Non Gauss-distribution

For a small sample from a normal or Gauss-distribution, it has been derived by Student with which factor one has to multiply the standard deviation of the sample such that, with a certain probability, the center of the distribution is found in the interval on both sides of the average of the sample, with sizeView problem details

Trespa – Pressing of a Corner Profile

In the fabrication of office desks and plates for walls, Trespa presses thermally layers of paper impregnated with resin. During the heating process (up to 160 degrees at 90 bar) polymerisation of the resin occurs and densification takes place up to 70 per cent. In a related process for the fabrication of wood fibre platesView problem details

Philips – The Behaviour of a Droplet of Polymer Solution in an Ink-jet Printer

Light-emitting polymer displays are a new, interesting flat display principle. The active material in the display is a  very thin semiconducting polymer layer of order 100 nanometer. To obtain these thin layers a small concentration of the polymer is dissolved in a suitable solvent. Different colours can be obtained with different polymers. To make aView problem details

Nederlands Forensisch Instituut – Probability Model for Marks and Prints

From the Nederlands Forensisch Instituut there are two related problems, one about so-called tool marks and the other about shoeprints. Toolmarks appear when at a burglary a tool (a screwdriver or crowbar) is being used to break a door or window open. This tool leaves a mark: in the doorpost for example a mark orView problem details

KLM – Performance Forecast of a Flight Schedule

In search of a quick method to forecast the quality of a flight schedule Situation KLM flies to over 150 destinations with 97 aircraft. Four times a year, a new flight schedule is developed. Though the operational feasibility is taken into account up to a certain degree during the development process, the aim at thatView problem details

Het Nationaal Beiaard Museum – Hanging a Carillon in a Broek-system

A carillon consists of approximately 20 up to 45 bells. These bells hang in an open lantern-tower (like the Munttoren in Amsterdam) or inside a tower under the roof. A carillon is played using a keyboard that is generally located one story below the bells. A wire connects each clapper to the keyboard. The oldestView problem details

RIVO – Problems Surrounding the Expanding Pacific Oyster in the Eastern Scheldt

History of oysters Flat oysters have been commercially cultured in the Eastern Scheldt Estuary (The Netherlands) since 1875. After the severe winter of 1962/1963, which caused high mortality, the stock was diminished. Searching for alternatives, Dutch oyster farmers introduced the Pacific oyster to the Eastern Scheldt in 1964. The Pacific oyster is native to Japan.View problem details

NMI – Weighing Schemes

For the calibration of weights with various nominal masses, metrology institutes use special weight sets. For instance, the decade from 1000 g to 100 g is ‘covered’ by six weights: 1000 g, 500 g, 2 x 200 g and 2 x 100 g. In order to be able to distinguish between weights with the sameView problem details

SIG – Partitioning a Call Graph

A company has a large software system that has become costly to maintain. What they need to do is break the system into smaller more manageable modules. Of course, this is a job for a trained expert. However, when the system is largely an automated suggestion for a partition into modules is useful. Given aView problem details

IFKB – Spatiotemporal Patterns in High-density Surface Electromyography

Being recorded at the skin, a surface electromyographic signal (sEMG) reflects the electrical activity of an underlying muscle (or group of muscles). Hence, sEMG offers a fairly simple, non-invasive way to assess the activation of superficial muscles. The signal is an integral measure summing action potentials of many motor units, i.e. groups of muscle fibersView problem details

NFI – Dealing with Selection Effects in Forensic Science

Many areas of forensic science deal with questions concerning the selection of evidence. If certain features are used to select a suspect from a large group of potential suspects, can you use the same features as evidence in a legal case against the suspect? If the answer is yes, is the evidential value the sameView problem details

KLM – Planning Drinking Water for Airplanes

Part of the planning of each KLM flight consists in determining the quantity of drinking water to take on board. Risking a water shortage is not an option, whereas a surplus will cost unnecessary extra fuel. However, reading off the level of the water tanks can not be done accurately: on most airplanes, the waterView problem details

AMC – Warming up Bodies after Invasive Surgery

Hypothermia is used in a number of invasive cardiosurgical procedures. In limited hypothermia, a routine procedure in open-heart surgery, the human body is cooled down to 32 degrees Celcius, whereas in deep hypothermia, which is used less frequently, body temperatures go down as far as 20 degrees. The actual cooling of the body is doneView problem details

Chess – Gossiping to Optimality

Analysis and optimization of message delivery in wireless sensor networks Chess is a company of about 160 employees, with locations in Haarlem and Best, that offers products, solutions and services in the field of electronics, IT-applications and embedded software. One of the projects of Chess has to do with ‘wireless sensor networks’. Suppose that aView problem details

NMI – Calibration of Pressure Measurement

In pressure measurement, the value of pressure is determined by dividing the force exerted on a piston by the effective area of the piston. The effective area of the piston may differ from the actual area because of irregularities at the piston edge and because of leakage through the thin cavity between the piston andView problem details

TWARON – Bullet-proof Math

Twaron is a strong fiber. Teijin Twaron is a split off from AKZO-Nobel and is now part of Teijin, a Japanese company. Teijin Twaron is responsible for developing the Twaron fiber and its applications. One of the applications of Twaron is in bullet-proof vests. Twaron is interested in finding the velocity at which only aView problem details

Nucletron – Radiological Needlework

Nucletron is a high-tech, international company, that specializes in equipment for medical diagnostics. Problem description To treat prostate cancer with radiological techniques, the prostate is perforated with a number of needles. Before the radiological treatment may start, the exact positions of these needles must be known. To detect these positions, an ultra-sound sensor is used.View problem details

DSM – Catching Gas with Droplets

At DSM one is interested in the development of packaging materials that are not or little permeable for certain gases. Think of the packaging of meat in a polymer sheet, that should keep the meat free from oxygen. The idea to realize this is to include in the sheet of packaging material droplets that absorbView problem details

ASML – Optimizing Software Release Policy

ASML is a company located in Veldhoven that builds machines for manufacturers of computer chips. The software of these machines ASML sells now consists of one large package, a so-called monolith. Their current policy is to release a new version of this entire monolith approximately every nine months. This monolithic approach has a few disadvantages.View problem details

Regge en Dinkel – Mathematical challenge waterboard

Mathematical challenge waterboard Regge en Dinkel The waterboard Regge en Dinkel is responsible for the watermanagement of 1300 km2 in the eastern part of the Netherlands. The expected climate change will affect the watersystem; more and heavier rainfall will result in increasing discharge en flooding. The waterboard has three strategies to deal with these problems:View problem details

UMC – Rapid Calculation of the Radiofrequency Field Pattern in MRI

Introduction The physical principle of MRI is based upon the application of a strong static magnetic field to the patient. This field forces the magnetic spin moment of hydrogen nuclei in the patients to precess around the external field with a particular frequency which scales proportionally with the magnetic field strength. Central in the imagingView problem details

AMC – Modeling a Heart Pump

In acute heart failure, the cardiologist or cardiothoracic surgeon may introduce a catheter-mounted pump into the left heart chamber. The left heart chamber is responsible for maintaining the circulation through the following organs: brains, muscles, intestines, kidneys etc. Therefore, acute heart failure, and specifically heart failure of the left chamber, results in so-called cardiogenic shockView problem details

KLM – Optimizing the Reserve Strategy of Cabin Crew

The cabin crew of KLM receives a new roster every week, which shows their assignment for the next several weeks. A typical flight assignment consists of several days of duty followed by a number of days off. Such a combination of duty time and free time is fixed for each type of flight and isView problem details

ING – Improving an Equity Option Pricing Model

Introduction Volatility, i.e., the uncertain fluctuations in the prices of financial assets such as stocks, is of paramount importance in financial markets theory and practice. Volatility characterizes the risk of an investment. Moreover, volatility is a major determinant of the price of a financial derivative. A financial derivative is a contract that derives its valueView problem details

Innogrow – Optimizing a Closed Greenhouse

Innogrow develops and sells a new type of greenhouse, called GeslotenKas®. By closing the windows of a greenhouse and providing it with an integrated climate and energy system, maximal control is obtained over the growth factors and energy use. The closed greenhouse also functions as an energy source. Excess heat is saved in seasonal energyView problem details

ASML – A Sampling Problem

ASML develops machines to perform the very critical lithographic step in the process of integrated circuit manufacturing. Lithography boils down to exposing a photo lacquer (resist) present on a silicon plaque (wafer) with ultraviolet light using a mask (glass plate called reticle with a chrome pattern, derived from the integrated circuit layout, on it). TheView problem details

Equalis – Equalizing the Cost of Health Insurance

In the Netherlands, health care expenses show major differences amongst regions. For instance, citizens of Heerlen had average health care costs of 2811 euro per insured, whereas this was only 1.633 euros in Urk (published by Vektis, a collaboration of health insurance companies). A possible explanation might be that citizens of Urk have a betterView problem details

Centraal Planbureau – Economic Optimal Water Safety

Economic optimal water safety in the Netherlands is since the flood disaster of 1953 an important topic in policy and research. CPB published in 1954 a (social) cost-benefit analysis (CBA) of a comprehensive plan to increase the water security of the Netherlands (Tinbergen, J., 1954, The economic balance of the Delta plan, annex to theView problem details

MARIN – Parametric Roll of Ships

Introduction ‘Parametric roll’ is a phenomenon that sometimes suddenly occurs to ships sailing in the head or following seas. Apparently, without any clear reason, the amplitude of the roll motion (i.e. the rotation about the longitudinal axis of the ship) increases within a couple of roll periods, from a few degrees to above 45 degrees.View problem details

KNMI – An Objective Method to Associate Local Weather Extremes

Local weather extremes, like heavy rainfall or extreme temperatures, are usually connected to characteristic circulation patterns in the atmosphere. The figure below illustrates this fact for daily mean temperatures in July and August as observed in De Bilt. For two periods with extremely high temperatures the atmospheric circulation deviation from the time-mean flow as characterizedView problem details

DSM – Stiffening While Drying

Introduction Nowadays waterborne coatings (WBC’s) are increasingly replacing traditional organic solvent-borne coatings (SBC’s) in many applications due to stricter legislation originating from an ever-growing environmental awareness in society. One of the few disadvantages of WBC’s is that they generally require longer drying times as compared to SBC’s. For that reason, the drying process of WBC’sView problem details

DHV – Water Pumping Optimization

Grimsby Region In the figure, the schematic representation of the Grimsby drinking water supply region is given. Characteristics are: The supply regions Smithville, Beamsville, and Grimsby are situated at different heights With the use of the water buffers and the water pumps drinking water is transported to the three supply regions. The Pumps can beView problem details

Albemarle – Mixing and Modelling: How Mathematics May Mix Molecules

Introduction Albemarle is a big chemical concern with about 3700 employees and many plants worldwide. It is a manufacturer of polymers and fine chemicals, including additives and intermediates used in agricultural and cleaning products, drilling compounds, etcetera. Since mixing of different chemical compounds is one of its core techniques, Albemarle  Research in Amsterdam (former AkzoView problem details

Stork – Modeling Compressible Non-Newtonian Chicken Flow

Stork Food Systems Stork Food Systems is the supplier of processing systems for poultry and fresh meat. As a technology market leader, with more than 45 years of experience, process knowledge and proven track record worldwide, we support and equip food processors to create maximum process value now and in the future. Problem description InView problem details

Phytocare – Modeling and Optimization of Algae Growth

Problem description The runoff water from greenhouses contains fertilizers and must be cleaned before it can be returned to the groundwater system. A means of doing this is to introduce algae into the water. The algae eat up the fertilizer and clean the water. Subsequently, the algae may be removed and sold as feed, forView problem details

MARIN – Thruster Allocation for Dynamical Positioning

MARIN, the Maritime Research Institute Netherlands, has become a reliable, independent, and innovative service provider for the maritime sector and a contributor to the well being of society. MARIN has been expanding the boundaries of maritime understanding with hydrodynamic research for over 70 years. Today, this research is applied for the benefit of Concept Development,View problem details

KEMA – Optimal Distributed Power Generation Under Network-Load Constraints

Leading authority in energy consulting and testing & certification. A global, leading authority in energy consulting and testing & certification, active throughout the entire energy value-chain – in a world of increasing demand for energy, KEMA has a major role to play in ensuring the availability, reliability, sustainability, and profitability of energy and related productsView problem details

ESA – Position Estimating in Peer-to-Peer Networks

The European Space Agency (ESA) is an agency for cooperation among the European States in space research, technology, and space applications. One of the topics of ESA is Satellite Navigation, being responsible for the construction of the Galileo system and an augmentation-system for GPS. Satellite Navigation has many applications, including route guidance for cars, theView problem details

Statkraft – Strategic Bidding in a Primary Reserve Auction

In any electric system, the generation has to match the consumption at all times. In the European interconnected (UCTE) grid, this balance is maintained by Primary Reserve. The four German grid operators procure their demand of Primary Reserve by means of a monthly auction, which results are publicly accessible. Generation units that can participate inView problem details

NXP – Routing for Analog Chip Designs at NXP Semiconductors

The increasing demand for smaller, faster, and multi-functional electronic devices such as smartphones is one of the driving forces in the semiconductor industry. Combined with requirements on power usage, sustainability, and wireless functionality this is generating challenges in several domains. During the design of the layout, which is a representation of the chip in shapesView problem details

NFI – Statistical Modelling of Pre-Impact Velocities in Car Crashes

Causing a lethal vehicle accident as a driver is a serious offense. Especially if driving speed was excessive, imprisonment for a substantial time is likely. The Netherlands Forensic Institute is frequently asked to estimate driving speed based on accident scene data. Estimation is based on a physics model that simulates the crash itself and theView problem details

Marin – Analysis of a Model for Ship Maneuvering

Traditionally, the study of the hydromechanical behaviour of ships (and floating bodies in general) is divided into ship hydrostatics (without motions in calm water) and ship hydrodynamics (with motions in either calm water or in waves and/or current). The area of ship hydrodynamics can be roughly divided into powering/propulsion and calm water resistance, seakeeping (motionsView problem details

Deltares – Optimal Flood Control

We are interested in the most appropriate way of formulating optimum control problems for heterogeneous, partially controllable water resources systems. These systems often need implicit time-stepping schemas for avoiding restrictive stability criteria. This distinguishes them from most technical systems on which control is applied. We are interested in various methods to solve the optimal controlView problem details

Chess – Node Counting in Wireless Ad-hoc Networks

A defining characteristic of wireless ad hoc networks is their dynamic behavior. In practice, it is not uncommon to find that the topology of even a small network deployed in a controlled environment changes from one moment to the next, without apparent changes to the layout of the nodes. This behavior stems from the inherentView problem details

Thales – Optimization of the Lifetime of Sensor Networks

Sensor networks and networks of wearable communication systems (for example networks that support emergency workers in their efforts) have strong requirements for their energy consumption. Instead of only focusing on minimization of energy consumption of the individual nodes (which leads to locally optimal solutions)  it is important to maximize the lifetime of the whole network.View problem details

TataSteel – Image Recognition of Shape Defects in Hot Steel Rolling

Tata Steel is the 2nd largest steel producer in Europe with major manufacturing sites in the UK, the Netherlands, Germany, France, and Belgium. The IJmuiden site in The Netherlands hosts a fully integrated production process in which coils of coated steel strips are produced out of raw materials such as iron ore and coal. HotView problem details

Philips – A New Ray-tracing Method for Non-imaging Optics

Introduction In illumination engineering, the transfer of light from the source to the target is computed to obtain photometric quantities like the luminous intensity, color point, and brightness. The technique that is commonly used is the Monte Carlo (MC) ray tracing method that traces randomly rays through an optical system containing components like lenses andView problem details

MARIN – Structural Integrity of Marine Structures

Operators of ships and offshore structures face the responsibility of maximizing the operational window while taking care of the safety onboard.  Periodic inspections help the operator to assess if the structure is still in one piece and whether repairs are required. Continuous monitoring of the structure’s response as motions and stresses is increasingly used toView problem details

Endinet – Future Challenges in the Electricity Grid

Endinet is a network company that distributes electricity and gas to various customers in the province of North-Brabant of the Netherlands. Endinet owns the medium (10kV) and low voltage (230V) networks of Eindhoven and a part of Veldhoven and is responsible for the operation and maintenance of these networks. Most of the network operators inView problem details

Bartels – Building a Mountain in The Netherlands

God created the world and the Dutch created the Netherlands. This old and popular expression among Dutch people could get a completely new meaning. After the polders, dikes, and Delta works, the Dutch may have a new flagship: the Dutch mountain. The idea started as a column by journalist and former professional cyclist Thijs Zonneveld.View problem details

KNMI – Fog Detection from Camera Images

KNMI products and services rely heavily on observations. Besides increasing amounts of data from traditional sources (such as observation networks), the use of open data, crowd-sourced data and the Internet of Things (IoT) is rapidly emerging.  To deploy these sources of data optimally, the KNMI DataLab has been established. Data‐driven innovations that arise from public‐privateView problem details

RWS – Effective Water Storage as Flood Protection

Effectief water bergen: De mogelijkheden van Rijnstrangen als retentiegebied voor bescherming tegen overstromingen. De Nederlandse dijken zijn gedimensioneerd op een bepaalde afvoer die (statistisch gezien) eens in de 1250 jaar voorkomt. Dat wil zeggen dat hogere afvoeren tot overstromingen kunnen leiden, maar dat lagere afvoeren veilig (dat wil zeggen zonder overstromingen) via de rivieren afgevoerdView problem details

Philips – The Random Disc Thrower Problem

Philips Research is a global organization that helps Philips introduce meaningful innovations that improve people’s lives. We provide technology options in the area of health and well-being for both developed and emerging markets. Positioned at the front-end of the innovation process, we work on everything from spotting trends and ideation to proof of concept andView problem details

TNO – Stress Fields Inside of a Neck for more Accurate Crash Analysis

Background As a material (typically, a metal) is stretched, it can reach a point where all of the strain (deformation) is concentrated in just one area. For example, notice in the figure below how the material has become very narrow across a short length in the specimen which was initially cylindrical. This condition is calledView problem details

Fytagoras – Oxygen Transport in Germinating Seeds

Seed germination in most seeds depends on the availability of oxygen. Living seeds start respiration upon imbibitions and respiration accelerates at the moment the germination really commences. The availability of oxygen to the embryo in the seed depends on the oxygen concentration around the seed, the respiration rate of the cells (in the embryo), andView problem details

Heineken – Estimates on Returnable Packaging Material

Heineken Global Logistics is our international supply chain knowledge center, located in Zoeterwoude, the Netherlands. The Corporate Distribution & Logistics Department (CDL) delivers a significant contribution to the development of the Heineken business worldwide through business improvement projects, knowledge development initiatives, and policymaking in the area of distribution & logistics. One of the knowledge areasView problem details

NedCoffee – Coffee Market Volatility

Coffee is a tropical product, produced in over 50 developing countries. It makes an important contribution to socio-economic development and poverty alleviation and is of exceptional importance to exporting countries, some of which rely on coffee for over half their export earnings. For the 25 million smallholder farmers and their families who produce 80% ofView problem details

NS – Energy-efficient Railway Timetabling

Environmental and economic considerations urge companies to seek better, more efficient ways of using available resources. Energy is one of these resources, and railway systems are large consumers of electricity, indeed. Even the slightest improvement in the energy consumption of trains can lead to very visible effects, helping to reduce CO2 emissions and to improveView problem details

INCAS3 – Nonlinear Cochlear Mechanics

It is perhaps astonishing that in spite of the advances in medical imaging and other research techniques, the possibilities of visualizing damage to the human hearing system are very limited. Although there is a vast range of audiological tests that measure the effect of damage, pinpointing what is causing these effects is often impossible. This,View problem details

Human hearing system

Witteveen+Bos – Monitoring the Sewer System

The old city centre of Delft is sensitive to both pluvial and fluvial flooding, especially specific areas in the eastern part of the city centre. This includes surcharging of sewers and flooding of streets and buildings due to storm events, overflowing of canals and high groundwater levels. In order to reduce flooding impacts, the canalsView problem details

WLN – A Statistical Tool for Water Quality Monitoring

For 30 years WLN safeguards the quality of drinking water in Groningen and Drenthe. By using chemical, biological and technological research protects the quality of the drinking water that water company Groningen and water transportation company Drente provide. Quality control is essential for WLN. Background Measuring the quality of drinking water is WLN’s core business.View problem details

HZPC – The Mathematics of French Fries

HZPC is the world-leading developer and seller of high-quality seed potatoes. It is a Dutch company with offices in Metslawier and Joure that operates internationally and that employs over 230 people. To serve its customers better, it also performs research in the growth and processing of its potato varieties. This project is related to theView problem details

Mathematics of French fries

CBS – Calculating Traffic based on Road Sensor Data

The Nationale Databank Wegverkeergegevens (NDW), a database for traffic data, contains the counts of more than 14,000 traffic loops, that are to be found in the Dutch system of motorways and provincial roads. During a day it is analysed how many vehicles of which type pass through these loops each minute. Each day this givesView problem details

Marel Stork – Chilling on the Chicken Express

System information In a processing line products hang, on a constant pitch, in a shackle, the shackle is attached to a chain by means of a trolley, on the other side the trolley has wheels that run of a profile. The assembly is called the overhead conveyor. The endless chain is running the whole productionView problem details

Ortec Finance – Forecasting Financial Scenarios using Expert Opinions

1   About Ortec Finance Ortec Finance is a company of about 200 employees and its two main offices are located in Rotterdam and Amsterdam. The central mission of Ortec Finance is improving financial decision-making and monitoring by providing understanding, transparency and control through a combination of market knowledge, mathematical models, and Information Technology (IT). PensionView problem details

HZPC – Predicting Early Bulking in Potatoes

Tuber bulking is the 4th growth stage in the development of potato. Tuber cells expand with the accumulation of water, nutrients, and carbohydrates. Tubers become the dominant site for the deposition of carbohydrates and mobile inorganic nutrients. In breeding we are looking for early bulking varieties (to be able to harvest most kg in desirableView problem details

Dümmen Orange – Optimal Cutting Strategies for Flowers

Dümmen Orange is a leading company in the breeding and development of cut flowers, potted plants, bedding plants, and perennials with over a century of experience in the horticultural industry. In addition to a large marketing and sales network, Dümmen Orange has a strong network of production locations. In these production centra, so-called mother plantsView problem details

MARIN – System Parameter Identification in Numerical Simulations

A common problem in numerical simulations is finding the correct parameter values of a mathematical model. A typical example from MARIN practice is the simulation of a ship manoeuvre, like a zig-zag or a turning circle (Figure 1), where the result is compared with the outcome of an experiment. The forces acting on the shipView problem details

NMGroup – Power Line Route Optimisation in a Finite Spatial Grid

Building new infrastructure such as transmission lines, roads, rail, etc. is always a source of controversy. High voltage transmission lines blight the landscape they are constructed on, bringing social, environmental, and economic detriment to the areas they run through, equally they form the fabric of modern infrastructure enabling efficient transfer of power across the country.View problem details

NKI – Accurate Dose Delivery for Radiation Therapy: Adapting Treatment to Daily Anatomy

For radiation oncology, we treat patients with head and neck tumours over the course of 6-7 weeks. This treatment is usually based on one CT scan prior to treatment. We use that as an input for dose calculations in the patient based on a collapsed cone superposition algorithm. To optimise the dose distribution we useView problem details

NKI

Mobidot – Mobility Profiling from Smartphone Sensor Data: Confidently Know How People Travel

Our SWI problem formulation focuses on advancing the quality of our data derivation. Mobidot infers the route, role, objective, and mode of transportation from Smartphone data. Smartphones possess a variety of sensors, including GPS, mobile telephone (4G) and wi-fi signals, accelerometer-based mode, etc. that can be used to determine the motion and position of theView problem details

Mobidot

KNMI – Synchronizing Numerical Models of the Atmosphere to Improve Weather and Climate Predictions

Systems as diverse as clocks, singing crickets, cardiac pacemakers, firing neurons and applauding audiences exhibit a tendency to operate in synchrony. The phenomenon that dynamical systems synchronise their behaviour by some form of information exchange is known as synchronisation. In recent years, the concept of synchronisation is being applied in weather and climate research. ObservedView problem details

SKF – Statistical Modelling of Mechanical Bearing Life Testing

The goal is to model and optimize bearing life testing time under constraints. The constraints are from various kinds: Number of available test machines (each machine has 2 test positions): Number of life tests to be run: Statistical distribution assumed for individual bearing life: Weibull (,) Assessed precision: the expected maximum ratio between confidence boundsView problem details

Philips – Patient Adaptive Compressed Sensing

The Problem The sampling density function in Compressed Sensing can best be optimized once the -space density is known for the object under investigation. This is characterized by an MRI scan (fast pre-acquired data set), from which the -space extent is estimated by a Fourier Transform. In addition, the data is acquired with multiple, spatially-localized,View problem details