Quadratically Tight Relations for Randomized Query Complexity

Let $f:\{0,1\}^n \rightarrow \{0,1\}$ be a Boolean function. The certificate complexity $C(f)$ is a complexity measure that is quadratically tight for the zero-error randomized query complexity $R_0(f)$: $C(f) \leq R_0(f) \leq C(f)^2$. In this paper we study a new complexity measure that we call expectational certificate complexity $EC(f)$, which is also a quadratically tight bound on $R_0(f)$: $EC(f) \leq R_0(f) = O(EC(f)^2)$. We prove that $EC(f) \leq C(f) \leq EC(f)^2$ and show that there is a quadratic separation between the two, thus $EC(f)$ gives a tighter upper bound for $R_0(f)$. The measure is also related to the fractional certificate complexity $FC(f)$ as follows: $FC(f) \leq EC(f) = O(FC(f)^{3/2})$. This also connects to an open question by Aaronson whether $FC(f)$ is a quadratically tight bound for $R_0(f)$, as $EC(f)$ is in fact a relaxation of $FC(f)$. In the second part of the work, we upper bound the distributed query complexity $D^\mu_\epsilon(f)$ for product distributions $\mu$ by the square of the query corruption bound ($\mathrm{corr}_\epsilon(f)$) which improves upon a result of Harsha, Jain and Radhakrishnan [2015]. A similar statement for communication complexity is open.Comment: 14 page

Multivariate adaptive regression splines for estimating riverine constituent concentrations

Regression-based methods are commonly used for riverine constituent concentration/flux estimation, which is essential for guiding water quality protection practices and environmental decision making. This paper developed a multivariate adaptive regression splines model for estimating riverine constituent concentrations (MARS-EC). The process, interpretability and flexibility of the MARS-EC modelling approach, was demonstrated for total nitrogen in the Patuxent River, a major river input to Chesapeake Bay. Model accuracy and uncertainty of the MARS-EC approach was further analysed using nitrate plus nitrite datasets from eight tributary rivers to Chesapeake Bay. Results showed that the MARS-EC approach integrated the advantages of both parametric and nonparametric regression methods, and model accuracy was demonstrated to be superior to the traditionally used ESTIMATOR model. MARS-EC is flexible and allows consideration of auxiliary variables; the variables and interactions can be selected automatically. MARS-EC does not constrain concentration-predictor curves to be constant but rather is able to identify shifts in these curves from mathematical expressions and visual graphics. The MARS-EC approach provides an effective and complementary tool along with existing approaches for estimating riverine constituent concentrations

Evaluation of EC-Funded Mine Action in South East Europe | 2002-2007

The EC Anti-Personnel Landmine Regulation of 2001 mandated evaluation of EC Mine Action strategy every three years. The first report was a Global Evaluation published in 2005, this report forms one part of the 2008 evaluation by regions and covers South East Europe, 2002-2007. The approach used for the evaluation was desk research visits to two mine-affected countries (Bosnia and Herzegovina and Croatia) and further contact with EC Delegations by phone and internet. Face-to-face discussions with RELEX and EuropeAid staff in Brussels were only possible after the country visits

Partnership for impact: EC, IFAD, and CIAT

The European Commission (EC) joined CGIAR in 1977 and is one of the largest multilateral donors and investors, helping set research priorities, contributing scientific expertise and policy advice, and providing financial support. Europe’s strategic investments in CIAT’s research, administered by IFAD, over the years have made significant impact in strengthening food security, protecting natural resources, and fostering inclusive and sustainable economic development for smallholder farmers and rural communities

Does Exposure and Receptivity to E-cigarette Advertisements Relate to E-cigarette and Conventional Cigarette Use Behaviors among Youth? Results from Wave 1 of the Population Assessment of Tobacco and Health Study

Background: E-cigarettes (EC) are the most commonly used tobacco product among youth. Additionally, youth EC users are progressing to smoking conventional cigarettes (CC). Although known to target youth, there are no current restrictions in the US on EC marketing, including advertising. The purpose of this study is to evaluate the relationship between EC advertisements and youth EC and CC use behaviors. Methods: This study analyzed data from youth (12-17 years) aware of EC in Wave 1 (2013-2014) of the Population Assessment of Tobacco and Health (PATH) study (n=12,199). Weighted logistic regression models assessed whether exposure and receptivity to any of five randomized EC ads (two TV and three print) were associated with the outcomes of EC and CC behaviors of ever use, current (past 30 day) use, and susceptibility to future use. Additional analyses determined whether EC advertising exposure and EC and CC behaviors associations were moderated by EC advertising receptivity. All models were adjusted for sociodemographics, other combustible tobacco product use, and parent smoking. Results: EC advertisement exposure was significantly associated to ever and current EC use as well as susceptibility to EC and CC (p Conclusion: These findings demonstrate exposure to EC advertisements are particularly associated with EC use behaviors, but could play a role in future CC use as well. Youth who are receptive to EC advertisements appear particularly vulnerable. Further studies should focus on the role of receptivity to EC advertisements among youth in order to support regulatory policy targeting EC advertising

Direct measurement of electrocaloric effect in lead-free Ba(SnxTi1-x)O3 ceramics

In this study, we report on investigation of the electrocaloric (EC) effect in lead-free Ba(SnxTi1-x)O3 (BSnT) ceramics with compositions in the range of 0.08 ≤ x ≤ 0.15 by the direct measurement method using a differential scanning calorimeter. The maximum EC temperature change, ΔTEC-max = 0.63 K under an electric field of 2 kV/mm, was observed for the composition with x = 0.11 at ∼44 °C around the multiphase coexistence region. We observed that the EC effect also peaks at transitions between ferroelectric phases of different symmetries. Comparison with the results of indirect EC measurements from our previous work shows that the indirect approach provides reasonable estimations of the magnitude of the largest EC temperature changes and EC strength. However, it fails to describe correctly temperature dependences of the EC effect for the compositions showing relaxor-like behaviour (x = 0.14 and 0.15) because of their non-ergodic nature. Our study provides strong evidence supporting that looking for multiphase ferroelectric materials can be very useful to optimize EC performance

Temporal response to harmonic driving in electroconvection

The temporal evolution of the spatially periodic electroconvection (EC) patterns has been studied within the period of the driving ac voltage by monitoring the light intensity diffracted from the pattern. Measurements have been carried out on a variety of nematic systems, including those with negative dielectric and positive conductivity anisotropy, exhibiting "standard EC" (s-EC), those with both anisotropies negative exhibiting "non-standard EC" (ns-EC), as well as those with the two anisotropies positive. Theoretical predictions have been confirmed for stationary s-EC and ns-EC patterns. Transitions with Hopf bifurcation have also been studied. While traveling had no effect on the temporal evolution of dielectric s-EC, traveling conductive s-EC and ns-EC patterns exhibited a substantially altered temporal behavior with a dependence on the Hopf frequency. It has also been shown that in nematics with both anisotropies positive, the pattern develops and decays within an interval much shorter than the period, even at relatively large driving frequencies.Comment: 19 pages, 5 figure

Prospects for computational steering of evolutionary computation

Currently, evolutionary computation (EC) typically takes place in batch mode: algorithms are run autonomously, with the user providing little or no intervention or guidance. Although it is rarely possible to specify in advance, on the basis of EC theory, the optimal evolutionary algorithm for a particular problem, it seems likely that experienced EC practitioners possess considerable tacit knowledge of how evolutionary algorithms work. In situations such as this, computational steering (ongoing, informed user intervention in the execution of an otherwise autonomous computational process) has been profitably exploited to improve performance and generate insights into computational processes. In this short paper, prospects for the computational steering of evolutionary computation are assessed, and a prototype example of computational steering applied to a coevolutionary algorithm is presented