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In today's complex and dynamic supply chain markets, information systems are essential for effective supply chain management. Complex decision making processes on strategic, tactical, and operational levels require substantial timely support in order to contribute to organizations' agility. Consequently, there is a need for sophisticated dynamic product pricing mechanisms that can adapt quickly to changing market conditions and competitors' strategies. We propose a two-layered machine learning approach to compute tactical pricing decisions in real-time. The first layer estimates prevailing economic conditions -- economic regimes -- identifying and predicting current and future market conditions. In the second layer, we train a neural network for each regime to estimate price distributions in real-time using available information. The neural networks compute offer acceptance probabilities from a tactical perspective to meet desired sales quotas. We validate our approach in the Trading Agent Competition for Supply Chain Management. When competing against the world's leading agents, the performance of our system significantly improves compared to using only economic regimes to predict prices. Profits increase significantly even though the prices and sales volume do not change significantly. Instead, tactical pricing results in a more efficient sales strategy by reducing both finished goods and components inventory costs.

The complexity and dynamics of current military operations demand reliable and up-to-date intelligence and in particular near-real-time threat assessment. This paper explores the potential of operational analysis techniques in supporting military personnel in processing information from different sources, in order to constantly carry out near-real time threat assessments of current situations and future developments. It introduces a near-real time threat assessment approach that integrates Bayesian Belief Networks and spatio-temporal modelling. This approach has been implemented in a near-real-time intelligence demonstrator to support threat assessment during operations.

Most of the developed Governments, active in reaping the benefits of E-Governance, nowadays have discovered the threats of this new approach too. They invest massively to cope with the highly complex decision making systems of today, dramatic changes in economy, technology and Information Warfare threats plus government’s own changing strategies. This creates challenges with respect to matching decision-making structures. E-Governance Frameworks is defined by the UNESCO as “the use of ICT (Information and communication technologies) by different actors of the society with the aim to improve their access to information and to build their capacities”. It may be expected that E-governance will have more strategic importance for many governments and that its concepts and tools will develop dramatically in the coming decade. This will raise the urgencies and importance of protecting government decision making processes from non-solicited disturbing external or internal interferences. Security is critical to the success of any E-Governance framework. Since such governance frameworks somehow will be open to interactions with different “stakeholders” Internally (within the boundaries of the state, like pressure groups, political parties, business, citizens ..) or Externally (e.g. other states, multinational businesses, worldwide operating malicious organizations,..) who may influence the decision making process in government, create political pressure or even start a cyberwar, by making use of E-governance frameworks. This raises a number of prevention issues to cope with, like instability of the decision making processes, or even instability of real development processes in states. This causes efforts to add to the design process of E-Governance frameworks a new dimension, popularly labeled “Information Warfare Strategy”, with the aim to build in existing and future E-Governance Frameworks safeguarding tools; to prevent abuse of such frameworks in practical government decision cases. Traditionally there is a distinctionbetween military vs. non-military approaches. The question has to be raised in how far a distinction between Technology (ICT) vs. non-Technology tools (like diplomacy, or legal) will be more appropriate. However we have to recognize that any line of distinction is arbitrary and will show the need for some dynamics, because parties involved will learn and improve.

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Four students of InHolland University Delft have started the mechanical design of an autonomous portable observational unmanned lightweight airship (POULA). Their main objectives where to make the airship as light and simple as possible. This has resulted in an airship with only two propellers which can be independently rotated around their common axis. Little or no attention is paid regarding the dynamics and controllability of the airship. Because it was questionable if the strongly nonlinear and underactuated airship would be controllable this had to be investigated first. This investigation is the main subject of the research presented in this report. Because no mathematical model was available the first part of the report concerns the derivation of the kinematic and dynamic model. Initially it was the intention to design a three dimensional nonlinear control system and therefore the model obtained is three dimensional as well. However, this appeared to be a bridge too far for this research. Instead the model is simplified to two dimensions. The purpose of the airship will be to monitor a certain indoor area like a gym with an onboard camera. After the airship has been released in the air the first task of the control system is to let the airship ascent to a desired altitude. After this task is accomplished the airship is ready to track a certain (time-varying) trajectory to surveil the area. A constant altitude is desired during this operation. First the model has been simplified to a two dimensional model in the longitudinal plane. A controller is designed to let the airship ascent to a certain starting position. Because the model is still underactuated it is linearized. Linear state feedback controllers are obtained using the pole placement method. Simulations show that the system can be stabilized and that the controller is able to let the errors converge to zero. When the airship has reached its desired height it is ready to start his surveilling task. Because the desired altitude is constant the model is considered in the horizontal plane. The main assumption is that the airship is neutrally buoyant, i.e. the altitude remains constant during the operation without providing a propeller force upwards. Because of the underactuated design and the non-negligible nonlinear terms it is a very hard control problem. A lot of literature is available how to deal with this problem. Different strategies with different constraints have been proposed. Considering these different constraints and the objectives for the airship there has been chosen to follow the strategy used for controlling an underwater vessel. The method presented in the paper has been adjusted and modified to make it suitable for the airship. First a trajectory planning algorithm is proposed specifying all the necessary reference states. These states are used as an input for the nonlinear controller which is based on Lyapunov techniques. Practical exponential stability is proven. Simulations show that the airship can be stabilized and is able to track a time-varying sinusoidal trajectory with and without model errors and time-varying disturbances. In future research the three dimensional model will have to be used to obtain a three dimensional control system. Literature is available which describe strategies to design this control system. Based on the two dimensional results presented in this report and the available literature it does seem possible to control the airship POULA. It will be possible to surveil indoor areas using the onboard camera.

De Wiskunde Olympiade: iedereen heeft er wel eens van gehoord. Omdat ie zelf als scholier ooit meegedaan hebt aan één of meer ronden van deze wedstrijd, omdat je verhalen van studenten hebt gehoord die het olympiadetrainingsprogramma doorlopen hebben, of omdat je collega's hebt die betrokken zijn bii de organisatie van de Internationale Wiskunde Olympiade (International Mathematical Olympiad, IMO) in 2011 In Nederland. Voor iedereen die nu wel eens wil weten hoe de olympiade precies in elkaar zit, hier zeven vragen en antwoorden, over alles van de eerste ronde tot en met IMO 2011 in Nederland. Birgit van Dalen en Quintijn Puite vertellen graag over alle Ins en outs.

Our research is focused on the effects of the additionof procurement information (offer prices) to a sales-based economic regime model. This model is used for strategic, tactical, and operational decision making in dynamic supply chains. We evaluate the performance of the regime model through experiments with the MinneTAC trading agent, which competes in the TAC SCM game. The new regime model has an overall predictive performance which is equal to the performance of the existing model. Regime switches are predicted more accurately, whereas the prediction accuracy of dominant regimes does not improve. However, because procurement information has been added to the model, the model has been enriched, which gives new opportunities for applications in the procurement market, such as procurement reserve pricing.

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We describe a method for constructing a model of second order dependent type theory out of a model of classical second order predicate logic. Apart from the construction being of interest by itself, this also suggests a way of proving the completeness of the formulas-as-types embedding from second order predicate logic to second order dependent type theory. Under this embedding, formulas are interpreted as types, and derivability (of a formaula) in the logic should correspond to inhabitation (i.e. the associated type being nonempty) in the type system. This correspondence works in one way (called soundness): if a formula is derivable, then the associated type is inhabited (there is a term of that type). It's an open problem whether the correspondence works in the other direction (called completeness): if the type associated with formula ϕ is inhabited, then ϕ is derivable. Now, the completeness would be proved if any model M of second order logic could be extended to a model S(M) of second order dependent type theory in a faithful way, i.e. for all formulas ϕ, ϕ is true in M if and only if ϕ is inhabited in S(M). Here we prove this equivalence for models M that are full models of classical second order predicate logic. The extension of M to S(M) is constructed by adding to the basic domain of M all λ-terms and defining a smart equivalence relation on the set we thus obtain. The types are then interpreted as subsets of terms of this extended λ-calculus. The models construction is a variant of the one defined in [Stefanova and Geuvers 1996] for the Calcuklus of Constructions.

Objectives Wood dust is known to be associated with a range of respiratory effects including reduced lung function, increased bronchial responsiveness and occupational asthma. Cross-sectional studies have suggested an excess of asthma symptoms and lung function decline in sawmill workers. The study aims were to measure the incidence of new-onset asthma, to examine longitudinal changes in lung function, and associations with dust exposures. Methods Associations between dust exposures, asthma symptoms and lung function were studied over three years in a prospective cohort of sawmill workers. Respiratory morbidity was assessed using spirometry and symptom questionnaires, and personal dust exposure was measured, initially on recruitment into the study and then annually for at least two years. Results We recruited 281 sawmill workers from seven sawmills. Wood dust sampling (n = 300) showed an overall average of GM = 0.6 mg/m 3 (GSD 3.41), range 3 . Asthma symptoms were more common in workers with high exposure compared to the reference group with low exposures (OR = 1.31, 95% CI = 0.45–3.83). The incidence of new-onset asthma was 4.6% overall, and 8% among those with high “dry”dust exposure. In the longitudinal follow-up of workers a clear decline in forced expiratory volume in 1 second (FEV 1 ) and maximal mid expiratory flow (MMEF) was evident in the high exposure group, when compared with the non/low-exposed. Although the numbers were small, the decline over the 3 years in both FEV 1 and MMEF was statistically significant in the high exposure group. Conclusions This study confirms that New Zealand sawmill workers generally experience levels of dust exposure below most exposure standards. Notwithstanding this, there is evidence of an increased risk of developing asthma symptoms and lung function decline (of an obstructive nature) over time even at low dust levels, with a suggestion of a dose-response relationship between dust levels and the development of symptoms.