Comparison of different measures for quantum discord under non-Markovian noise

Two geometric measures for quantum discord were recently proposed by Modi et al. [Phys. Rev. Lett. 104, 080501 (2010)] and Dakic et al. [Phys. Rev. Lett. 105, 190502 (2010)]. We study the similarities and differences for total quantum correlations of Bell-diagonal states using these two geometry-based quantum discord and the original quantum discord. We show that, under non-Markovian dephasing channels, quantum discord and one of the geometric measures stay constant for a finite amount of time, but not the other geometric measure. However, all the three measures share a common sudden change point. Our study on critical point of sudden transition might be useful for keeping long time total quantum correlations under decoherence.Comment: 10 pages, 3 figures submitted for publicatio

Crosslinguistic trends in tone change A review of tone change studies in East and Southeast Asia

Ground-breaking studies on how Bangkok Thai tones have changed over the past 100 years (Pittayaporn 2007, 2018; Zhu et al. 2015) reveal a pattern that Zhu et al. (2015) term the “clockwise tone shift cycle:” low > falling > high level or rising-falling > rising > falling-rising or low. The present study addresses three follow-up questions: (1) Are tone changes like those seen in Bangkok Thai also attested in other languages? (2) What other tone changes are repeated across multiple languages? (3) What phonetic biases are most likely to be the origins of the reported changes? A typological review of 52 tone change studies across 45 Sinitic, Tai-Kadai, Hmong-Mien, and Tibeto-Burman languages reveals that clockwise changes are by far the most common. The paper concludes by exploring how tonal truncation (Xu 2017) generates synchronic variation that matches the diachronic patterns; this suggests that truncation is a key mechanism in tone change

Single-input and single-output (SISO) controller reduction based on the L1L_1-norm

This paper proposes a new method to solve the controller-reduction problem based on the $L_1$-norm. This method uses a reduced-order closed-loop system to deduce reduced-order controllers. The problem of obtaining the required lower-order closed-loop system was formulated as an $L_1$-norm optimization, and the conditions were provided for guaranteeing the internal stability and the existence of lower-order controllers from the obtained reduced-order closed-loop system. In addition, the particle swarm optimization and sequence linear programming were adopted to solve the resultant $L_1$-norm optimization. Two numerical examples demonstrated the effectiveness of the proposed method

Entanglement of separate nitrogen-vacancy centers coupled to a whispering-gallery mode cavity

We present a quantum electrodynamical model involving nitrogen-vacancy centers coupled to a whispering-gallery mode cavity. Two schemes are considered to create W state and Bell state, respectively. One of the schemes makes use of the Raman transition with the cavity field virtually excited; The other enables the Bell state preparation and quantum information transfer by virtue of dark state evolution and adiabatic passage, which is tolerant to ambient noise and experimental parameter fluctuations. We justify our schemes by considering the experimental feasibility and challenge using currently available technology.Comment: 8 pages and 5 figure

Tragedy of the commons in online social search

Online social search (OSS) brings forth a new way to harness the Internet for answers. In this paper, we study the non-cooperation problem in OSS. We propose an analytical model that captures the behavior of OSS nodes, and, from a gaming-strategy point of view, analyze various strategies an individual node can utilize to allocate its awareness capacity. Based on this we derive the Pareto inefficiency in terms of the system cost. We also propose an incentive scheme under which the optimal state of individual nodes is also optimal for the whole system. Extensive simulations show that the strategy under our proposed incentive mechanism outperforms other strategies in terms of the system cost and the search success rate. To the best of our knowledge, this is the first study of the tragedy-of-the-commons problem in OSS. © 2011 IEEE.published_or_final_versionThe 2011 IEEE International Conference on Communications (ICC 2011), Kyoto, Japan, 5-9 June 2011. In Proceedings of ICC 2011, 2011, p. 1-

Development of domestic and international computer forensics

With the increasing of computer crime, instant emergence of new digital product, new computer technology and computer forensics technology is promoted, developed constantly. This paper described basic information/content of computer forensics, and elaborated the development of current computer forensics at domestic and overseas market. The trends of computer forensics are pointed out and recent hot topics of research are introduced. © 2011 IEEE.published_or_final_versionThe 7th International Conference on Intelligent Information Hiding and Multimedia Signal Processing (IIH-MSP 2011), Dalian, China, 14-16 October 2011. In Proceedings of the 7th IIH-MSP, 2011, p. 388-39

An incentive scheme for non-cooperative social networks under the Independent Cascade Model

Session 20: Intelligent e-Technology IIn this paper we analyze influence maximization for noncooperative social networks under the Independent Cascade Model. We propose a model of noncooperative nodes and prove some interesting properties of this model. Based on this, we further develop a game-theoretic model to characterize the behavior of noncooperative nodes, and design a Vickrey-Clarke-Groves-like scheme to incentivise cooperation. An advertiser can resolve the negative effect of noncooperation with our proposed solution. Evaluation on large social networks demonstrates the importance of cooperation and the effectiveness of our proposed incentive scheme in maximizing influence. We also discuss the budget allocation between seed nodes activation and incentives to non-seed nodes.published_or_final_versio