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09:15  Getting tight error bounds in floatingpoint arithmetic: illustration with complex functions, and the real x^n function SPEAKER: JeanMichel Muller ABSTRACT. The specifications provided by the IEEE 754 standard for floatingpoint arithmetic allows one to design very simple algorithms for functions such as $x^n$, or complex multiplication and division, that are much more accurate that what one might think at first glance. We will show how tight error bounds are obtained for these algorithms, and discuss how generic exemples can be built to show the tightness of these error bounds. 
10:45  TheoremProving Analysis of Digital Control Logic Interacting with Continuous Dynamics SPEAKER: Jackson R. Mayo ABSTRACT. This work outlines an equationbased formulation of a digital control program and transducer interacting with a continuous physical process, and an approach using the Coq theorem prover for verifying the performance of the combined hybrid system. Considering thermal dynamics with linear dissipation for simplicity, we focus on a generalizable, physically consistent description of the interaction of the realvalued temperature and the digital program acting as a thermostat. Of interest in this work is the discovery and formal proof of bounds on the temperature, the degree of variation, and other performance characteristics. Our approach explicitly addresses the need to mathematically represent the decision problem inherent in an analogtodigital converter, which for rare values can take an arbitrarily long time to produce a digital answer (the socalled Buridan's Principle); this constraint ineluctably manifests itself in the verification of thermostat performance. Furthermore, the temporal causality constraints in the thermal physics must be made explicit to obtain a consistent model for analysis. We discuss the significance of these findings toward the verification of digital control for more complex physical variables and fields. 
11:15  Transformation of a PID Controller for Numerical Accuracy SPEAKER: Nasrine Damouche ABSTRACT. Numerical programs performing floatingpoint computations are very sensible to the way formulas are written. Several techniques have been proposed concerning the transformation of expressions in order to improve their accuracy and now we aim at going a step further by automatically transforming larger pieces of code containing several assignments and control structures. This article presents a case study in this direction. We consider a PID controller and we transform its code in order to improve its accuracy. The experimental data obtained when we compare the different versions of the code (which are mathematically equivalent) show that those transformations have a significant impact on the accuracy of the computations. 
11:45  Policy iteration in finite templates domain SPEAKER: Assale Adje ABSTRACT. We prove in this paper that Policy Iteration can be generally defined in finite domain of templates using Lagrange duality. Such policy iteration algorithm converges to a fixed point when for very simple technique condition holds. This fixed point furnishes a safe overapproximation of the set of reachable values taken by the variables of a program. We prove also that Policy Iteration can be easily initialised for small programs when templates are correctly chosen. 
14:30  Certifying Square Root and Division Elimination SPEAKER: Pierre Neron ABSTRACT. This paper presents a program transformation that removes square roots and divisions from functional programs without recursion, producing code that can be exactly computed. This transformation accepts different subsets of languages as input and it provides a certifying mechanism when the targeted language is Pvs. In this case, we provide a relation between every function definition in the output code and its corresponding one in the input code, that specifies the behavior of the produced function with respect to the input one. This transformation has been implemented in OCaml and has been tested on different algorithms from the NASA ACCoRD project. 
15:00  Computational complexity of iterated maps on points and sets SPEAKER: Christoph Spandl ABSTRACT. The computational complexity of the certified iteration of discrete dynamical systems is considered. Relations to the LyapunovExponents are shown. 
15:30  SetBased Decorated Intervals SPEAKER: Jürgen Wolff von Gudenberg ABSTRACT. The draft IEEE standard for interval arithmetic p1788 has recently been developed and will be open for public review in this summer 2014 In the talk we introduce the newly developed concepts such as setbased intervals, flavors, decorations or revers function evaluations 
16:30  Foundations and Technology Competitions Award Ceremony ABSTRACT. The third round of the Kurt Gödel Research Prize Fellowships Program, under the title: Connecting Foundations and Technology, aims at supporting young scholars in early stages of their academic careers by offering highest fellowships in history of logic, kindly supported by the John Templeton Foundation. Young scholars being less or exactly 40 years old at the time of the commencement of the Vienna Summer of Logic (July 9, 2014) will be awarded one fellowship award in the amount of EUR 100,000, in each of the following categories:
The following three Boards of Jurors were in charge of choosing the winners:
http://fellowship.logic.at/ 
17:30  FLoC Olympic Games Award Ceremony 1 SPEAKER: Floc Olympic Games ABSTRACT. The aim of the FLoC Olympic Games is to start a tradition in the spirit of the ancient Olympic Games, a Panhellenic sport festival held every four years in the sanctuary of Olympia in Greece, this time in the scientific community of computational logic. Every four years, as part of the Federated Logic Conference, the Games will gather together all the challenging disciplines from a variety of computational logic in the form of the solver competitions. At the Award Ceremonies, the competition organizers will have the opportunity to present their competitions to the public and give away special prizes, the prestigious Kurt Gödel medals, to their successful competitors. This reinforces the main goal of the FLoC Olympic Games, that is, to facilitate the visibility of the competitions associated with the conferences and workshops of the Federated Logic Conference during the Vienna Summer of Logic. This award ceremony will host the

18:15  FLoC Closing Week 1 SPEAKER: Helmut Veith 
16:30  Verifying Parameterized Software Models in Computational Data Science against Behavioral Specifications SPEAKER: Sumit Kumar Jha ABSTRACT. Computational data science uses a variety of numerical software models to understand, predict and control the evolution of complex systems. For example, computational systems biology employs multiscale mechanistic stochastic rulebased models while culturomics uses detailed agentbased models. Because of the inherent uncertainty involved in precisely measuring natural systems, software models employed in computational data science include a number of unknown or imprecisely known parameters. A fundamental problem in developing such software models is to discover the set of parameter values that enable a computational model to satisfy a given set of behavioral specifications. In this talk, we will present a new massively parallel extremescale parameter discovery algorithm for complex intelligent software models. We will discuss preliminary results obtained using a parallel implementation of the algorithm on a small 1,792core CUDA cluster. The talk will also identify opportunities for future research in verifying numerical software being deployed by computational data scientists. 