Ordered Measurements of Permutationally-Symmetric Qubit Strings

We show that any sequence of measurements on a permutationally-symmetric (pure or mixed) multi-qubit string leaves the unmeasured qubit substring also permutationally-symmetric. In addition, we show that the measurement probabilities for an arbitrary sequence of single-qubit measurements are independent of how many unmeasured qubits have been lost prior to the measurement. Our results are valuable for quantum information processing of indistinguishable particles by post-selection, e.g. in cases where the results of an experiment are discarded conditioned upon the occurrence of a given event such as particle loss. Furthermore, our results are important for the design of adaptive-measurement strategies, e.g. a series of measurements where for each measurement instance, the measurement basis is chosen depending on prior measurement results.Comment: 13 page

Boundary-induced violation of the Dirac fermion parity and its signatures in local and global tunneling spectra of graphene

Extended defects in graphene, such as linear edges, break the translational invariance and can also have an impact on the symmetries specific to massless Dirac-like quasiparticles in this material. The paper examines the consequences of a broken Dirac fermion parity in the framework of the effective boundary conditions varying from the Berry-Mondragon mass confinement to a zigzag edge. The parity breaking reflects the structural sublattice asymmetry of zigzag-type edges and is closely related to the previously predicted time-reversal symmetric edge states. We calculate the local and global densities of the edge states and show that they carry a specific polarization, resembling, to some extent, that of spin-polarized materials. The lack of the parity leads to a nonanalytical particle-hole asymmetry in the edge-state properties. We use our findings to interpret recently observed tunneling spectra in zigzag-terminated graphene. We also propose a graphene-based tunneling device where the particle-hole asymmetric edge states result in a strongly nonlinear conductance-voltage characteristics, which could be used to manipulate the tunneling transport.Comment: 8 pages, 5 figures, to be published in Phys. Rev.

An Efficient Algorithm for Optimizing Adaptive Quantum Metrology Processes

Quantum-enhanced metrology infers an unknown quantity with accuracy beyond the standard quantum limit (SQL). Feedback-based metrological techniques are promising for beating the SQL but devising the feedback procedures is difficult and inefficient. Here we introduce an efficient self-learning swarm-intelligence algorithm for devising feedback-based quantum metrological procedures. Our algorithm can be trained with simulated or real-world trials and accommodates experimental imperfections, losses, and decoherence

Sounds Like a Fit! Wording in Recruitment Advertisements and Recruiter Gender Affect Women’s Pursuit of Career Development Programs via Anticipated Belongingness

Following calls for research to increase gender equality, we investigated women's intentions to pursue career opportunities, in the form of career development programs. We built on lack of fit and signaling theory to argue that women's but not men's pursuit of career opportunities would be influenced by recruiter gender and gender‐stereotypical wording in recruitment advertisements. We conducted two studies in Germany. In Study 1 (video‐based experiment with 329 university students), we found that when a male recruiter used stereotypically masculine compared to feminine wording, female students anticipated lower belongingness, expected lower success of an application, and indicated lower application intentions for career opportunities. These differences in female students’ evaluations disappeared when the recruiter was female. While Study 2 (experimental vignette study with 545 employees) replicates the negative effects of masculine wording for female employees; the buffering effect of female recruiters was only replicated for younger, but not for older female employees. Women's anticipated belongingness mediated the relationship between advertisement wording and application intentions when the recruiter was male. Recruiter gender and wording had no effects on men. Our work contributes to a better understanding of when and why contextual characteristics in the recruitment process influence women's pursuit of career opportunities

New flexible motion estimation technique for scalable MPEG encoding using display frame order and multi-temporal references

The applicability of MPEG video coding can be improved by scaling both the algorithmic complexity and resource usage appropriately for the intended device and application. For this purpose, we present a new technique for motion estimation, based on a scalable three-stage process including frame processing in display order, approximation of motion vector fields using multiple references and optional quality refinements. Experiments show that the computational effort is scalable with a factor of 14, resulting in a global variation of 7 dB SNR in picture quality. At full processing, our technique slightly outperforms a 32×32 full search motion estimation. The technique forms a valuable contribution to mobile MPEG coding applications, following the scalability concepts introduced by Mietens, de With and Hentschel (see IEEE Int. Conf. on Image Proc. (ICIP 2001), vol.3, p.462-465, Oct. 2001)

Метод трёхстороннего слияния онтологий на языке OWL 2

Предложен алгоритм трёхстороннего слияния онтологий при многопользовательском редактировании путём попарного сравнения онтологий, основанный на выявлении совпадающих и конфликтующих изменений. Разработана программная реализация алгоритма