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We consider the number of quantum queries required to determine the coefficients of a degree-d polynomial over F_q. A lower bound shown independently by Kane and Kutin and by Meyer and Pommersheim shows that d/2 + 1/2 quantum queries are needed to solve this problem with bounded error, whereas an algorithm of Boneh and Zhandry shows that d quantum queries are sufficient. We show that the lower bound is achievable: d/2 + 1/2 quantum queries suffice to determine the polynomial with bounded error. Furthermore, we show that d/2 + 1 queries suffice to achieve probability approaching 1 for large q. These upper bounds improve results of Boneh and Zhandry on the insecurity of cryptographic protocols against quantum attacks. We also show that our algorithm’s success probability as a function of the number of queries is precisely optimal. Furthermore, the algorithm can be implemented with gate complexity poly(log(q)) with negligible decrease in the success probability. We end with a conjecture about the quantum query complexity of multivariate polynomial interpolation.

The purpose of this study is to provide insight into the factors that determine the willingness of brand owners in the Dutch food industry to adopt bio-based plastic packaging. In order to obtain an answer first a conceptual model is developed based on the Five Forces model by Porter, and Roger’s adoption theory. To better determine the appropriate indicators for the measurement of the concepts a pilot consisting of expert interviews is performed. The data for this study is collected by means of an online survey sent to all brand owners in the Dutch food industry. Descriptive statistics of the survey data show that there are only two groups of bio-based plastic adopters among Dutch brand owners: those that are currently considering bio-based plastic packaging, and those that have not considered it yet. Due to the low number of completed questionnaires advanced multivariate statistical methods cannot be used for data analysis. Instead the data analysis is performed using independent T-tests of means for both brand owner groups. These tests identify incentives from the food service industry, expected opportunities for CO2 reduction on both the short-term and long-term, and the importance of the brand name in decision-making as factors that determine the willingness of brand owners to adopt bio-based plastic packaging. The tests also shows that in particular large brand owners, both in terms of employees and packaging volume, are considering the use of bio-based plastic packaging. That brand owners are at best just considering bio-based plastic, and that there are only a few doing even that, indicates that while bio-based plastic packaging remains a substitute product within an already existing industry, it appears to be distinctive enough from petroleum-based packaging to initiate a new product life cycle. Another indication is that the food service industry currently has a more prominent role than retailers due to their stronger customer relationship and higher margi

Self-tested quantum information processing provides a means for doing useful information processing with untrusted quantum apparatus. Previous work was limited to performing computations and protocols in real Hilbert spaces, which is not a serious obstacle if one is only interested in final measurement statistics being correct (for example, getting the correct factors of a large number after running Shor's factoring algorithm). This limitation was shown by McKague et al. to be fundamental, since there is no way to experimentally distinguish any quantum experiment from a special simulation using states and operators with only real coefficients. In this paper, we show that one can still do a meaningful self-test of quantum apparatus with complex amplitudes. In particular, we define a family of simulations of quantum experiments, based on complex conjugation, with two interesting properties. First, we are able to define a self-test which may be passed only by states and operators that are equivalent to simulations within the family. This extends work of Mayers and Yao and Magniez et al. in self-testing of quantum apparatus, and includes a complex measurement. Second, any of the simulations in the family may be used to implement a secure 6-state QKD protocol, which was previously not known to be implementable in a self-tested framework. © 2011 Springer-Verlag.

Op 1 januari 2001 was het zover. Op deze datum was Rotterdam officieel herpolderd. Daarmee werd het waterkwantiteitsbeheer binnen Noord Rotterdam overgedragen aan Schieland. Het waterkwaliteitsbeheer was al veel langer een taak van Schieland. Aan de westzijde van Rotterdam is het waterkwantiteitsbeheer overgedragen aan het hoogheemraadschap van Delfland en ten zuiden van de Nieuwe Maas aan het waterschap IJsselmonde. Hoe is het Schieland vergaan in de aanloop van de herpoldering en na januari 2001?

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