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In an active radar-tracking system, the target-motion model is usually modeled in the Cartesian coordinates, while the radar measurement usually is obtained in polar/spherical coordinates. Therefore the target-tracking problem in the Cartesian coordinates becomes a nonlinear state estimation problem. A number of measurement-conversion techniques, which are based on position measurements, are widely used such that the Kalman filter can be used in the Cartesian coordinates. However, they have fundamental limitations to result in filtering performance degradation. In fact, in addition to position measurements, the Doppler measurement or range rate, containing information of target velocity, has the potential capability to improve the tracking performance. A filter is proposed that can use converted Doppler measurements (i.e. the product of the range measurements and Doppler m easurements) in the Cartesian coordinates. The novel filter is theoretically optimal in the rule of the best linear unbiased estimation among all linear unbiased filters in the Cartesian coordinates, and is free of the fundamental limitations of the measurement-conversion approach. Based on simulation experiments, an approximate, recursive implementation of the novel filter is compared with those obtained by four state-of-the-art conversion techniques recently. Simulation results demonstrate the effectiveness of the proposed filter. [ABSTRACT FROM AUTHOR]

Antitumor activity has been reported for turmeric, the dried rhizome of Curcuma longa. This study proposes a new feature selection method for the identification of the antitumor compounds in turmeric total extracts. The chemical composition of turmeric total extracts was analyzed by gas chromatography-mass spectrometry (21 ingredients) and high-performance liquid chromatographymass spectrometry (22 ingredients), and their cytotoxicity was detected through an 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay against HeLa cells. A support vector machine for regression and a generalized regression neural network were used to research the composition-activity relationship and were later combined with the mean impact value to identify the antitumor compounds. The results showed that six volatile constituents (three terpenes and three ketones) and seven nonvolatile constituents (five curcuminoids and two unknown ingredients) with high absolute mean impact values exhibited a significant correlation with the cytotoxicity against HeLa cells. With the exception of the two unknown ingredients, the identified 11 constituents have been reported to exhibit cytotoxicity. This finding indicates that the feature selection method may be a supplementary tool for the identification of active compounds from herbs. [ABSTRACT FROM AUTHOR]

χcJ (J=0, 1, 2) production associated with a charm quark pair in hadron collisions is calculated in the framework of nonrelativistic QCD at the Tevatron and LHC. It is found that the color-singlet contribution is small and the color-octet contribution may be dominant in the large pT region. The differential cross section of pp¯ →χc+cc¯ is at least 1 order of magnitude smaller than the next-to-leading order result of χcJ inclusive production pp¯ → χc+X; therefore χcJ production in pp¯ → χc+cc¯ may have negligible influence on the ratio Rχc=σχc2/σχc1 measured by CDF Collaboration at the Tevatron. The feed-down contribution from χcJ+c+c¯ to J/Ψ+c+c¯ is found to be large compared with J/Ψ direct production and may have important influence on the measurement of J/Ψ+c+c¯. The validity of fragmentation approximation for the process is also discussed. [ABSTRACT FROM AUTHOR]

There are three types of dynamical equations for a post-Newtonian Lagrangian formulation of three black holes. They are approximate post-Newtonian Lagrangian equations of motion, coherent post-Newtonian Lagrangian equations of motion, and post-Newtonian Hamiltonian canonical equations. The energy integral is conserved approximately in the first model, but exactly in the second and third models. The three formulations are not exactly equivalent, while they are approximately related in the orbital dynamical behavior. Figure-eight orbits in the three problems may have different initial conditions. Imai, Chiba, and Asada adjusted the initial velocities satisfying the figure-eight orbits for given initial positions in the first model. The initial velocities are still suitable for the figure-eight orbits of the latter two models when the initial separations of the first body are enough large. However, they are not generally applicable to relatively small initial separations in the three systems. We can obtain the desired initial velocities by scanning the initial velocities of the third body in the three systems. The figure-eight orbits in these models exhibit sensitive dependence on the scanned initial velocities for smaller initial separations. Although the differences in the scanned initial velocities among the three problems are minor for the small initial separations, the scanned initial velocities for any one of the three systems do not yield the figure-eight orbits for the other two systems. [ABSTRACT FROM AUTHOR]

We study a rapidly oscillating scalar field with potential V(ϕ)=k|ϕ|n nonminimally coupled to the Ricci scalar R via a term of the form (1-8πG0ξϕ²)R in the action. In the weak coupling limit, we calculate the effect of the nonminimal coupling on the time-averaged equation of state parameter γ=(p+ρ)/ρ. The change in ⟨γ⟩ is always negative for n≥2 and always positive for n<0.71 (which includes the case where the oscillating scalar field could serve as dark energy), while it can be either positive or negative for intermediate values of n. Constraints on the time variation of G force this change to be infinitesimally small at the present time whenever the scalar field dominates the expansion, but constraints in the early universe are not as stringent. The rapid oscillation induced in G also produces an additional contribution to the Friedman equation that behaves like an effective energy density with a stiff equation of state, but we show that, under reasonable assumptions, this effective energy density is always smaller than the density of the scalar field itself. [ABSTRACT FROM AUTHOR]

Bell tests, as primitive tools to detect nonlocality in bipartite systems, rely on an assumption, i.e., measurement independence. Since ensuring measurement independence in a practical Bell test is difficult, it is crucial to explore the effects of relaxing this assumption. Recently, in the simplest Clauser-Horne-Shimony-Holt Bell (CHSH-Bell) test, Koh et al. [Phys. Rev. Lett. 109, 160404 (2012)] built the relation among measurement dependence, guessing probability, and the maximum value of CHSH-Bell correlation function that an adversary (Eve) can fake. As well, Pope et al. [Phys. Rev. A 88, 032110 (2013)] and Yuan et al. [Phys. Rev. A. 91, 032111 (2015)] settled the same problem in the multiple-run scenario with the general input distribution and the factorizable one, respectively. However, pertinent results in the generalized CHSH-Bell test are still missing. Here, we study this problem and establish the relation among measurement dependence, guessing probability, and the maximum value of the generalized CHSH-Bell correlation function that Eve can fake. Furthermore, we also consider the multiple-run scenario and show the relations in both input distributions. Interestingly, compared with the simplest CHSH-Bell test, we find that it is more difficult for Eve to fake a violation in the generalized CHSH-Bell test in some special cases. We expect that our conclusions will serve as a reference for quantum information processing tasks such as quantum key distribution, randomness expansion, and other tasks in the device-independent framework. [ABSTRACT FROM AUTHOR]

Quantum walks with memory (QWM) are a type of modified quantum walks that record the walker's latest path. As we know, only two kinds of QWM have been presented up to now. It is desired to design more QWM for research, so that we can explore the potential of QWM. In this work, by presenting the one-to-one correspondence between QWM on a regular graph and quantum walks without memory (QWoM) on a line digraph of the regular graph, we construct a generic model of QWM on regular graphs. This construction gives a general scheme for building all possible standard QWM on regular graphs and makes it possible to study properties of different kinds of QWM. Here, by taking the simplest example, which is QWM with one memory on the line, we analyze some properties of QWM, such as variance, occupancy rate, and localization. [ABSTRACT FROM AUTHOR]

The surface water of 10 major river systems across China has been under intermediate pollution with striking eutrophication problems in major lakes (reservoirs). More data from the Ministry of Environmental Protection of China showed that underground water in 57% of monitoring sites across Chinese cities was polluted or extremely polluted. Rural water pollution, the rising number of incidents of industrial pollution, outdated sewerage systems, and the overuse of pesticides and chemical fertilizers also endanger the health of rural inhabitants in China. Nearly 0.2 billion rural residents could not use drinking water in accordance with the national standard, and there were reports of 'cancer villages' and food-borne diseases (cancer village refers to a village where a certain proportion of its inhabitants suffer from the same kind of cancer or where there is a hike in cancer incidence in that area). This study aims to raise awareness of the prevention and control of water pollution and to propose a set of national research and policy initiatives for the future safety of the water environment in China. [ABSTRACT FROM AUTHOR]

Reports on the increased sales of varying styles of prose collections in major Chinese cities such as Beijing, Shanghai and Guangzhou. Examples of best-selling works in China; Chinese scholars' optimism about the future of the prose craze.

We have proved that new randomness can be certified by partially free sources using 2→1 quantum random access code (QRAC) in the framework of semi-device-independent (SDI) protocols [Y.-Q. Zhou, H.-W. Li, Y.-K. Wang, D.-D. Li, F. Gao, and Q.-Y. Wen, Phys. Rev. A 92, 022331 (2015)]. To improve the effectiveness of the randomness generation, here we propose the SDI randomness expansion using 3→1 QRAC and obtain the corresponding classical and quantum bounds of the two-dimensional quantum witness. Moreover, we get the condition which should be satisfied by the partially free sources to successfully certify new randomness, and the analytic relationship between the certified randomness and the two-dimensional quantum witness violation. [ABSTRACT FROM AUTHOR]

By proposing device-independent protocols, Pironio et al. [Nature (London) 464, 1021 (2010)] and Colbeck et al. [Nat. Phys. 8, 450 (2012)] proved that new randomness can be generated by using perfectly free random sources or partially free ones as seed. Subsequently, Li et al. [Phys. Rev. A 84, 034301 (2011)] studied this topic in the framework of semi-device-independent and proved that new randomness can be obtained from perfectly free random sources. Here we discuss whether and how partially free random sources bring us new randomness in a semi-device-independent scenario. We propose a semi-device-independent randomness expansion protocol with partially free random sources and obtain the condition that the partially free random sources should satisfy to generate new randomness. In the process of analysis, we acquire a two-dimensional quantum witness. Furthermore, we get the analytic relationship between the generated randomness and the two-dimensional quantum witness violation. [ABSTRACT FROM AUTHOR]

We present experimentally derived potential curves and spin-orbit interaction functions for the strongly perturbed A ¹Σu+ and b³Π, states of the cesium dimer. The results are based on data from several sources. Laser-induced fluorescence Fourier transform spectroscopy (LIF FTS) was used some time ago in the Laboratoire Aimé Cotton primarily to study the X ¹Σg+ state. More recent work at Tsinghua University provides information from moderate resolution spectroscopy on the lowest levels of the b ³Π±0u state as well as additional high-resolution data. From Innsbruck University, we have precision data obtained with cold Cs2 molecules. Recent data from Temple University was obtained using the optical-optical double resonance polarization spectroscopy technique, and finally, a group at the University of Latvia has added additional LIF FTS data. In the Hamiltonian matrix, we have used analytic potentials (the expanded Morse oscillator form) with both finite-difference (FD) coupled-channel and discrete variable representation (DVR) calculations of the term values. Fitted diagonal and off-diagonal spin-orbit functions are obtained and compared with ab initio results from Temple and Moscow State universities. [ABSTRACT FROM AUTHOR]