Search

Shallow water waves phenomena in nature attract the attention of scholars and play an important role in fields such as tsunamis, tidal waves, solitary waves, and hydraulic engineering. Hereby, for the shallow water waves phenomena in various natural environments, we study the KdV–Calogero–Bogoyavlenskii–Schiff (KdV–CBS) equation. Based on the binary Bell polynomial theory, a new general bilinear Bäcklund transformation, Lax pair and infinite conservation laws of the KdV–CBS equation are derived, and it is proved that it is completely integrable in Lax pair sense. Various types of mixed solutions are constructed by using a combination of Homoclinic test method and symbolic computations. These findings have important significance for the discipline, offering vital insights into the intricate dynamics of the KdV–CBS equation. We hope that our research results could help the researchers understand the nonlinear complex phenomena of the shallow water waves in oceans, rivers and coastal areas. Furthermore, the present work can be directly applied to other nonlinear equations. • Lax pair and infinite conservation laws for the KdV–CBS equation are studied. • Proved that the KdV–CBS equation is completely integrable in Lax pair sense. • Various types of mixed solutions are constructed. • These new mixed solutions provide important insights for the KdV–CBS equation. [ABSTRACT FROM AUTHOR]

This paper presents the first experimental demonstration of a ternary memristor-CMOS logic family. We systematically design, simulate and experimentally verify the primitive logic functions: the ternary AND, OR and NOT gates. These are then used to build combinational ternary NAND, NOR, XOR and XNOR gates, as well as data handling ternary MAX and MIN gates. Our simulations are performed using a 50-nm process which are verified with in-house fabricated indium-tin-oxide memristors, optimized for fast switching, high transconductance, and low current leakage. We obtain close to an order of magnitude improvement in data density over conventional CMOS logic, and a reduction of switching speed by a factor of 13 over prior state-of-the-art ternary memristor results. We anticipate extensions of this work can realize practical implementation where high data density is of critical importance. [ABSTRACT FROM AUTHOR]

Composites are applied wildly in the engineering and some of them are composed of the transversely isotropic plate. In this paper, a refined analysis for the transversely isotropic plate under tangential loads is addressed based on the Green's function. The 3D Green's function for the transversely isotropic plate loaded by a tangential point force is derived in Section 2 . By adopting the general solution for the transversely isotropic material, a new harmonic function which contains undetermined constants is constructed. All stress components can be obtained by substituting the harmonic function into general solution. The constants can be determined by considering the equilibrium and boundary conditions of the plate. For the reason that this solution satisfies the 3D governing equations rigorously in everywhere of the plate, it is much more refined than that of the traditional plate theory, which is restricted by the thickness of plate. Numerical analysis in Section 3 is given to discuss the efficiency and accuracy of this method and study the stress distributions in the transversely isotropic plate loaded by the tangential point force and the tangential distributed load, respectively. [ABSTRACT FROM AUTHOR]

An optimization method of trajectory design is established in this paper for manned lunar landing circumlunar free-return flight mission. The problem of designing free-return trajectory with multiple constrains under the high precise dynamic model is converted to the nonlinear bounded optimization problems. A solving strategy consisting of hybrid and two-level optimization algorithm is then proposed. Under the double two-body model, the initial trajectory with the weak constrain conditions is obtained by hybrid optimization algorithm which consists of differential evolution (DE) method and sequence quadratic program (SQP) method based on the patched-conic approach. Then a two-level initial trajectory corrective measure based on the sequence quadratic program is applied to obtain the final solution satisfying the strong engineering constrains under the high precise dynamic model. Finally, the reliability and effectiveness of the approach proposed in this paper are demonstrated by the simulation tests, and the results indicate that the proposed method has excellent convergence performance and high precision, thus can be a useful tool for manned lunar orbit design. [ABSTRACT FROM AUTHOR]

The (2+1)-dimensional Korteweg-de Vries-Sawada-Kotera-Ramani (KdVSKR) equation which consists of the KdV equation and the SK equation is studied. Soliton molecules of the KdVSKR equation are given by means of the velocity resonance mechanism. By selecting the values of the phases, soliton molecule bounded by the three solitons is transferred to other type of the soliton molecule bounded by the asymmetric soliton and one soliton. Multi-breather solutions are derived by selecting the complex conjugate relations in the parameters. The relative positions for the maximum amplitudes of the multi-breathers can adjust with different values of the phases. It demonstrates that the phases of the multi-soliton solutions play an important effect in certain phenomena. In the meanwhile, the interactions between a soliton molecule and one-order breather, and between a soliton molecule and one-order lump of the KdVSKR equation are analyzed. The interactions are an elastic collisions by both the analytical and graphical ways. [ABSTRACT FROM AUTHOR]

Abstract: Population-based Algorithm Portfolios (PAP) is an appealing framework for integrating different Evolutionary Algorithms (EAs) to solve challenging numerical optimization problems. Particularly, PAP has shown significant advantages to single EAs when a number of problems need to be solved simultaneously. Previous investigation on PAP reveals that choosing appropriate constituent algorithms is crucial to the success of PAP. However, no method has been developed for this purpose. In this paper, an extended version of PAP, namely PAP based on Estimated Performance Matrix (EPM-PAP) is proposed. EPM-PAP is equipped with a novel constituent algorithms selection module, which is based on the EPM of each candidate EAs. Empirical studies demonstrate that the EPM-based selection method can successfully identify appropriate constituent EAs, and thus EPM-PAP outperformed all single EAs considered in this work. [Copyright &y& Elsevier]

Abstract: This work extends a recently proposed reversible data hiding (RDH) scheme of Li et al. which is based on pixel-value-ordering and prediction-error expansion. In Li et al.ʼs method, the maximum and minimum of a pixel block are predicted and modified to embed data. The pixel value order of each block is unchanged after data embedding and the property guarantees the reversibility. In this work, instead of the difference between the maximum and second largest value of a block (or, the minimum and second smallest value of a block) considered in Li et al.ʼs method, new differences are computed and new histogram-modification-strategy is utilized. Take the maximum for example, the new difference is defined considering the pixel locations of the maximum and second largest value. In this way, the blocks where the maximum equals to the second largest value can be exploited to embed data while these blocks suitable for RDH are not utilized in Li et al.ʼs work. This can better exploit image redundancy and achieve a superior embedding performance. Extensive experiments verify that the proposed method outperforms Li et al.ʼs and some other state-of-the-art works. [Copyright &y& Elsevier]

The AMS-02 Collaboration has just published a high-precision measurement of the cosmic positron fraction e+/(e- + e+), which rises with energy from ~5 GeV to ~350 GeV. The result indicates the existence of primary electron/positron sources to account for the positron excess. In this work, we investigate the possibility that the nearby mature pulsars with ages of O(105) yr are the primary positron sources. By fitting the data we find that the positrons from a single nearby pulsar, such as Geminga or Monogem, with the spectral index a ~ 2 can interpret the AMS-02 result. We also investigate the possibility that high-energy positrons are generated by multiple known pulsars in the ATNF catalogue. Such a scenario can also fit the AMS-02 data well. Future precise measurements of fine structures in the positron spectrum would be a support to the pulsar scenario. [ABSTRACT FROM AUTHOR]

We investigate the effect induced by the Kaluza-Klein (KK) graviten in the W+W-γ/Z production in the framework of the large extra dimensions (LED) model at both the CERN Large Hadron Collider (LHC) and the International Linear Collider (ILC). The integrated cross sections and various kinematic distributions in the LED model are presented and compared with those in the standard model. The results show that the contributions from KK-graviton exchange remarkably affect the observables of the triple gauge boson (W+W-γ/Z) production processes at both the ILC and LHC, particularly either in the high transverse momentum region or in the central rapidity region. We also find that the relative LED discrepancy for the W+W-γ/Z production at the LHC is generally larger than that at the ILC due to the additional LED contribution via gg fusion subprocess and the KK-graviton exchanging resonant effect induced by the continuous large colliding energy in pp collision. We conclude that the W+W-γ and W+W-Z productions at the LHC could have the distinct advantage over at the ILC from the aspect of effectively exploring the LED signal in measuring W+W-γ/Z production. [ABSTRACT FROM AUTHOR]

In this paper we study the Breit-Wigner enhancement of dark matter (DM) annihilation considering the kinetic decoupling in the evolution of DM freeze-out at the early Universe. Since the DM temperature decreases much faster (as \/R2) after kinetic decoupling than that in kinetic equilibrium (as 1/R2), we find the Breit-Wigner enhancement of the DM annihilation rate after the kinetic decoupling will affect the DM relic density significantly. Focusing on the model parameters that try to explain the anomalous cosmic positron/electron excesses observed by PAMELA/Fermi/ATIC, we find the elastic scattering Xf → Xf is not efficient in keeping dark matter in kinetic equilibrium, and the kinetic decoupling temperature Tkd is comparable to the chemical decoupling temperature Tf ∼ O(10) GeV. The reduction of the relic density after Tkd is significant and leads to a limited enhancement factor ∼O(102). Therefore, it is difficult lo explain the anomalous positron/electron excesses in cosmic rays by DM annihilation and give the correct DM relic density simultaneously in the minimal Breit-Wigner enhancement model. We also mention that if the nonthermal DM velocity distribution after kinetic decoupling or new scattering processes are considered, this constraint could be changed. [ABSTRACT FROM AUTHOR]

The technique of virtual baseline transformation is proposed to solve the phase ambiguity in the paper. It overcomes the multi-valued problem in the high frequency band effectively, and the mapping from directional feature to DOA becomes very simple. Then the unambiguous directional feature is used to train the Radial Basis Function Neural Network (RBFNN) for estimating the direction of arrival in broadband. The analysis and experimental results show that this method has a little computing burden and can avoid the phase ambiguity effectively. Further, the method is proved to be applicable to any uniform circular array (UCA) whose elements are equal or more than 5 (expect 6); The structure of DOA estimation model training with ambiguous directional features is simple, and the performance of model is better than modelling directly and correlation interferometer. So the proposed DOA estimation approach has a broad application future. [ABSTRACT FROM AUTHOR]

The spontaneous emission (SE) of the excited atoms in a two-dimensional (2D) arbitrary inhomogeneous environment has been systematically studied. Thelocal density of states, which determines the radiation dynamics of a point source (for 3D) or a line source (for 2D), in particular, the SE rate, is represented by the electric dyadic Green's function. The numerical solution of the electric Green's tensor has been accurately obtained with the finite-difference frequency-domain method with the proper approximations of the monopole and dipole sources. The SE of atoms in photonic crystal and plasmonic metal plates has been comprehensively and comparatively investigated. For both the photonic crystal and plasmonic plates systems, the SEs depend on their respective dispersion relations and could be modified by the finite-structure or finite-size effects. This work is important for SE engineering and the optimized design of optoelectronic devices. [ABSTRACT FROM AUTHOR]

Abstract: The 2D general solution for the plane problem of thermoelastic materials is derived in terms of three harmonic functions using strict differential operator theory for the case of distinct eigenvalues. Based on the obtained general solution, the 2D fundamental solution for a steady line heat source in an infinite and a semi-infinite thermoelastic plane is obtained by three newly introduced harmonic functions. All components of coupled fields are expressed in terms of elementary functions and they are convenient to be used. [Copyright &y& Elsevier]

Abstract: We use the compact mono-harmonic general solutions of transversely isotropic electro-magneto-thermo-elastic material to construct the three-dimensional Green’s function for a steady point heat source on the surface of a semi-infinite transversely isotropic electro-magneto-thermo-elastic material by five newly introduced mono-harmonic functions. All components of coupled field are expressed in terms of elementary functions and are convenient to use. Numerical results are given graphically by contours. [Copyright &y& Elsevier]

Abstract: Minimum aberration and clear criteria are two important rules for selecting optimal fractional factorial designs, in both unblocked and blocked cases. In this paper, we first show that under some given conditions, a blocked design having blocked minimum aberration is equivalent to D having minimum aberration. Let and . From the results of Tang et al. [Bounds on the maximum number of clear two-factor interactions for designs of resolution III and IV. Canad. J. Statist. 30 (2002) 127–136] and Wu and Wu [Clear two-factor interactions and minimum aberration. Ann. Statist. 30 (2002) 1496–1511], we know that the maximum number of clear two-factor interactions (2FIs) in designs is . Here it is proved that the maximum number of clear 2FIs in designs in blocks, denoted by , is also when . Furthermore, it is shown that any design that contains the maximum number of clear 2FIs is not a minimum aberration design, and this conclusion also holds when the design is a design with . [Copyright &y& Elsevier]

UN Secretary General António Guterres said October 8 that he had written to member states "about the worst cash crisis facing the UN in nearly a decade." According to the UN, the U.S. owes $674 million for the 2019 regular budget and $381 million for previous regular budgets. After Donald Trump assumed presidency in 2017, the U.S., waving the big stick of protectionism and unilateralism, wants to force UN policies to conform to its unilateral interests rather than to serve the common global governance. [Extracted from the article]

Abstract: Based on the governing equations of transversely isotropic magnetoelectroelastic media, four general solutions on the cases of distinct eigenvalues and multiple eigenvalues are given and expressed in five mono-harmonic displacement functions. Then, based on these general solutions, employing the trial-and-error method, the three-dimensional Green’s functions of infinite, two-phase and semi-infinite magnetoelectroelastic media under point forces, point charge and magnetic monopole are all presented in terms of elementary functions for all cases of distinct eigenvalues and multiple eigenvalues. Numerical results are also presented. [Copyright &y& Elsevier]

Supersaturated design is a form of fractional factorial design and has recently received much interest because of its potential in factor screening experiments. This paper mainly concerns the existing criteria for mixed-level designs, i.e. the χ2(D) criterion (for design D) proposed by Yamada and Matsui (J. Statist. Plann. Inference 104 (2002) 459), the E(fNOD) criterion proposed by Fang et al. (Metrika 58 (2003b) 279) and the minimum moment aberration (MMA) proposed by Xu (Statist. Sinica 13 (2003) 691). A lower bound of χ2(D) is obtained along with the sufficient and necessary condition for achieving it. The connections between χ2(D) and other criteria are discussed. Especially, it is shown that χ2(D) and the second power moment K2(D) are in fact equivalent to each other and hence the two criteria, χ2(D) and MMA, share the same optimal supersaturated designs, which can be constructed from saturated orthogonal arrays and other supersaturated designs. [Copyright &y& Elsevier]

Exact closed-solutions are obtained for the coupled field of a spheroidal magneto-electro-elastic inclusion in an infinite magneto-electro-elastic matrix subjected to spatially homogeneous mechanical and electromagnetic loadings far away from the inclusion. Three types of loadings are considered: axisymmetric, in-plane and out-of-plane shear. The limiting case of these solutions allows one to determine the complete coupled field in a magneto-electro-elastic material with a penny-shaped crack. Closed-form expressions for the stress, electric displacement and magnetic induction intensity factors of a penny-shaped crack are obtained. [Copyright &y& Elsevier]

The search for a compatible application of memristor-CMOS logic gates has remained elusive, as the data density benefits are offset by slow switching speeds and resistive dissipation. Active microdisplays typically prioritize pixel density (and therefore resolution) over that of speed, where the most widely used refresh rates fall between 25–240 Hz. Therefore, memristor-CMOS logic is a promising fit for peripheral I/O logic in active matrix displays. In this paper, we design and implement a ternary 1–3 line decoder and a ternary 2–9 line decoder which are used to program a seven segment LED display. SPICE simulations are conducted in a 50-nm process, and the decoders are synthesized on an Altera Cyclone IV field-programmable gate array (FPGA) development board which implements a ternary memristor model designed in Quartus II. Our approach to logic synthesis demonstrates a potential way forward for simulating large-scale memristor-CMOS circuits without embedded RRAM for functional verification, and our SPICE results show an improvement in data density of a variety of decoders by a factor between 3.6-8.5. While the switching speed of memristors are one of several bottlenecks to using them in combinational logic, the comparatively slow refresh rates of typical microdisplays indicate this to be a tolerable trade-off, which promotes data density over speed. [ABSTRACT FROM AUTHOR]

This paper presents a series of multi-stage hybrid memristor-CMOS ternary combinational logic stages that are optimized for reducing silicon area occupation. Prior demonstrations of memristive logic are typically constrained to single-stage logic due to the variety of challenges that affect device performance. Noise accumulation across subsequent stages can be amortized by integrating ternary logic gates, thus enabling higher density data transmission, where more complex computation can take place within a smaller number of stages when compared to single-bit computation. We present the design of a ternary half adder, a ternary full adder, a ternary multiplier, and a ternary magnitude comparator. These designs are simulated in SPICE using the broadly accessible Knowm memristor model, and we perform experimental validation of individual stages using an in-house fabricated Si-doped HfOx memristor which exhibits low cycle-to-cycle variation, and thus contributes to robust long-term performance. We ultimately show an improvement in data density in each logic block of between $5.2\times - 17.3\times $ , which also accounts for intermediate voltage buffering to alleviate the memristive loading problem. [ABSTRACT FROM AUTHOR]

The article is concerned with active disturbance rejection control of a heat equation. The considered heat equation satisfies the Dirichlet boundary condition on one part of the boundary. On the other part of the boundary is located a Neumann boundary control. The heat equation system suffers from both a model uncertainty in the heat flow modeling and an unknown external disturbance. Our control approach is based on the design of an exponentially converging observer to estimates both the state and the unknown uncertainty. The estimated state and the estimated uncertainty are used to build a stabilizing feedback control law such that the closed-loop system is exponentially stabilized, and the external disturbance is rejected. [ABSTRACT FROM AUTHOR]

Field-Coupled Nanocomputing technologies have great potential to surpass CMOS technology because of their lower power consumption and higher device concentration. To ease the burden of placement and routing (P&R) problems for FCN circuits, many delicate two-dimensional clocking schemes have been proposed, upon which algorithms can solve the P&R problems more strategically. In this paper, we propose a two-level optimization strategy by using a genetic algorithm (GA) combined with an enhanced A* algorithm. Some circuit design requirements, such as clock synchronization, layout area, etc., are cleverly designed in the fitness value function of the GA. Numerical results demonstrate the effectiveness of the hybrid algorithm. In particular, compared to current tools, such as fiction and Ropper, the proposed algorithm can achieve an optimal solution with a higher success rate and a sizeable applicable circuit scale. In addition, the concept of design rule checking (DRC) was proposed in FCN and integrated into the algorithm, making the P&R results mapping from gate-level to cell-level more smoothly. Besides, the number of cross wires is significantly reduced, and the distribution of IO ports can be more effectively controlled. [ABSTRACT FROM AUTHOR]

The AMS-02 Collaboration has just published a high-precision measurement of the cosmic positron fraction e+/(e-+e+), which rises with energy from ~5 GeV to ~350 GeV. The result indicates the existence of primary electron/positron sources to account for the positron excess. In this work, we investigate the possibility that the nearby mature pulsars with ages of O(105) yr are the primary positron sources. By fitting the data we find that the positrons from a single nearby pulsar, such as Geminga or Monogem, with the spectral index α~2 can interpret the AMS-02 result. We also investigate the possibility that high-energy positrons are generated by multiple known pulsars in the ATNF catalogue. Such a scenario can also fit the AMS-02 data well. Future precise measurements of fine structures in the positron spectrum would be a support to the pulsar scenario. [ABSTRACT FROM AUTHOR]

We study the prospect of dark matter (DM) searches in the monojet channel at future pp colliders with center-of-mass energies of 33, 50, and 100 TeV. We consider a class of simplified models in which a vector boson connecting DM particles to quarks is introduced. Comparing with studies in the effective field theory, the present framework gives more reasonable production rates and kinematics of the DM signatures. We estimate the sensitivities of future colliders with an integrated luminosity of 3 ab-1 to the DM-induced monojet signature and show the parameter space that can be explored. The constraints from direct and indirect DM detection experiments are compared with the future collider sensitivities. We find that the future collider detection will be much more sensitive than the indirect detection for the vector interaction and have better sensitivities than those of the direct detection by several orders of magnitude for the axial vector interaction. [ABSTRACT FROM AUTHOR]

We investigate the sensitivity to the effective operators describing interactions between dark matter particles and photons at future high energy e+e- colliders via the γ + ... channel. Such operators could be useful to interpret the potential gamma-ray line signature observed by the Fermi-LAT. We find that these operators can be further tested at e+e- colliders by using either unpolarized or polarized beams. We also derive a general unitarity condition for 2 → n processes and apply it to the dark matter production process e+e- → ξξγ. [ABSTRACT FROM AUTHOR]

As a well-motivated dark matter candidate, axions can be detected through the axion-photon resonant conversion in the magnetospheres of magnetic white dwarf stars or neutron stars. In this work, we utilize Omega Centauri, which is the largest globular cluster in the Milky Way and is suggested to be the remnant core of a dwarf galaxy, to probe the axion dark matter through radio signals that originate from all the neutron stars and magnetic white dwarf stars in it. With 100 h of observation, the combination of the radio telescopes Square Kilometer Array phase 1 and Low-Frequency Array can effectively probe the parameter space of the axion-photon coupling gaγ up to 10-14~10-15 GeV-1 for the axion mass range of 0.1~30 µeV. Depending on the choice of neutron star evolution model, this limitation is 2 or 3.5 orders of magnitude higher than that of the single neutron star or magnetic white dwarf. [ABSTRACT FROM AUTHOR]

In order to improve the quality of the signal obtained by analog Dechirp method and reduce the computation load of matched filtering after direct IF (Intermediate frequency) sampling, a digital Dechirp method combing the benefits of these two methods is proposed in this paper. By theoretical analysis, the mathematical model is obtained, and the data decimation and the filter design are also analyzed in detail for the realization of method provided in this paper. Compensation approach for the system distortion is also proposed. Simulation and analysis based on measured data prove the effectiveness and efficiency of the proposed strategy. [ABSTRACT FROM AUTHOR]

In this work, we study the constraints on the scenario of light stops and sbottoms in the next-to-minimal supersymmetric standard model (NMSSM), especially by a 125 GeV Higgs boson discovery and the LHC bounds on supersymmetry. The constraints from dark matter detections are also taken into account. From the parameter scan, we find that the NMSSM can well accommodate a light Higgs boson around 125 GeV and decay patterns. We would like to stress that the LHC direct supersymmetry searches with b tagging are very powerful and can set strong bounds on many NMSSM parameter points with light stops and sbottoms. We find t- → bχ1+ is a very promising channel for light stop detection if the mass splitting between χ1+ and χ10 is very small. It is also pointed out that in order to close the parameter space of light stops and sbottoms, new search strategies for signal channels such as pp →t~ltt~l → tt~ χt~10χt~10 and pp → b~lb~l → tt~W+W- χ~10χ~10 may be necessary. [ABSTRACT FROM AUTHOR]

The power information and the theory of radio propagation are introduced to the direction data association in passive cross location system, a novel data association algorithm based on received signal power estimation is proposed. The relationship between array manifold and received signal strength of covariance matrix estimation is derived. The high order power of inverse spatial covariance matrix is used to approximate the signal subspace, and the received signal power is obtained under the condition of known signal directions, thus avoiding the amplitude-attribute data association algorithm's disadvantage caused by the uncertainty noise and signal wave. The confidence level of each cross location is computed by using the relationship between the received power and the propagation decay. Through this way, the correct association is selected from the set of candidates. The simulation results confirm feasibility and superiority of the proposed method. [ABSTRACT FROM AUTHOR]

In this work, we study the light stop pair signals at the LHC. We explore the supersymmetry parameter space with nonuniversal gaugino and third-generation masses at the grand unified theory scale. Recent LHC supersymmetry search results based on 35 pb-1 and 1 fb-1 of data are implemented to put the limits on stop pair events. The dark matter relic density and direct detection constraints are also taken into account. Detailed simulations on the signals and background for some benchmark points are performed, and it is found that the stop pair signals usually escape the LHC search if the present cut conditions are used. We also explore the potential and sensitivity of ILC to probe such scenarios. It is found that the ILC can detect them with an integrated luminosity of a few tens of fb-1. [ABSTRACT FROM AUTHOR]

We study some properties of nucléons with a simplified version of a Faddeev equation at finite temperature and baryon chemical potential in the framework of the Nambu-Jona-Lasinio model. By taking diquark-quark bubble summation, we constructed the nucleón propagator and calculated the dynamical masses of the diquark and the nucleón in the pole approximation. We show that diquarks can survive as resonant states in the chiral symmetry restored phase at high temperature, and that nucléons are restricted in the chiral symmetry broken phase at low temperature. The phase diagram of the strongly interacting matter is then given. [ABSTRACT FROM AUTHOR]

• Topology identification with the synchronization process makes the uncertain system robust. • Complex-valued values extend the network model and time varying delays are more practical. • Two kinds of combination synchronizations are considered and the method is more general. • Adaptive controllers and parameter updating laws are designed to achieve synchronization. In this paper, the combination synchronization of time-varying complex-valued neural networks and parameter identification for unknown neural network topology are studied. Combination synchronization is a special synchronization for complex-valued system because real-part and imaginary-part make the neural state more complex than real system and the combination behaviors are more flexible. In addition, in the synchronization process, time-varying delays and unknown parameters are taken into consideration to make the network synchronization more practical and universal. In order to get the synchronization and identification, adaptive feedback control method is utilized and the adaptive combination synchronization controllers are proved with the Lyapunov stability theory. In the simulation, examples are given to demonstrate the robustness and effectiveness of the provided combination synchronizations. [ABSTRACT FROM AUTHOR]

We investigate the significance of a dark matter (DM) signal from the AMS-02 cosmic antiproton flux. Global fits to the data are performed under different propagation and hadronic interaction models. The uncertainties from the injection spectrum, propagation effects, and solar modulation of the cosmic rays are taken into account comprehensively. Since we need to investigate extended parameter regions with multiple free parameters in the fit, the machine learning method is adopted to maintain a realistic time cost. We find that a DM signal with DM mass ∼100  GeV or above 1 TeV would possibly be required. A comprehensive discussion is performed to clarify how are these uncertainties affecting the two kinds of DM signals. The low-energy DM signal is significant for the case with diffusive reacceleration propagation model + charge-independent solar modulation configuration. However, it is severely affected by the propagation and solar modulation effects. On the other hand, the high-energy DM signal is mainly influenced by the hadronic interaction model. Most of the hadronic interaction models do not indicate a significant high-energy DM signal except that the EPOS-LHC interaction model always requires a high-energy DM signal with a significance more than 5σ. [ABSTRACT FROM AUTHOR]

Abstract Recently, a new information hiding technology was proposed to hide a secret image into secret-fragment-visible mosaic image for secure image transmission. However, the previous method pays less attention to the block matching in the transform, and may obtain a low quality mosaic transform in some cases. In this paper, we propose to improve the secret-fragment-visible data hiding based the two-step energy function, which returns a weighted value of standard deviation and total variation of block. We match all the blocks according to the energy function and take the zero-mean normalized cross correlation (ZNCC) as the similarity measurement to optimize the matching. The interpolation optimization algorithm is used to stimulate the total ZNCC changes along with the parameter selection, and helps to solve the optimization quickly. Since more block's statistical properties are employed, the image blocks can be matched accurately, and a low distortion is introduced in the transform. Experimental results show that the proposed method can obtain a better visual quality of secret image after extraction and also requires less bits to encode the residuals. Highlights • A mosaic data hiding for secure image transmission based on two-step energy matching is proposed. • We employ the ZNCC to re-match the unsuitable matching for a better result. • We can optimize the overall block matching and obtain a better visual quality of restored image. • The interpolation method is used to solve the optimization quickly. [ABSTRACT FROM AUTHOR]

We investigate the effect of fermionic electroweak multiplet dark matter models on the stability of the electroweak vacuum using two-loop renormalization group equations (RGEs) and one-loop matching conditions. Such a treatment is crucial to obtain reliable conclusions, compared with one-loop RGEs and tree-level matching conditions. In addition, we find that the requirement of perturbativity up to the Planck scale would give strong and almost mass-independent constraints on the Yukawa couplings in the dark sector. We also evaluate these models via the idea of finite naturalness for the Higgs mass fine-tuning issue. [ABSTRACT FROM AUTHOR]

Searching for γ rays from dwarf spheroidal galaxies (dSphs) is a promising approach to detect dark matter (DM) due to the high DM densities and low baryon components in dSphs. The Fermi-LAT observations from dSphs have set stringent constraints on the velocity independent annihilation cross section. However, the constraints from dSphs may change in velocity dependent annihilation scenarios because of the different velocity dispersions in galaxies. In this work, we study how to set constraints on the velocity dependent annihilation cross section from the combined Fermi-LAT observations of dSphs with the kinematic data. In order to calculate the γ ray flux from the dSph, the correlation between the DM density profile and velocity dispersion at each position should be taken into account. We study such correlation and the relevant uncertainty from kinematic observations by performing a Jeans analysis. Using the observational results of three ultrafaint dSphs with large J-factors, including Willman 1, Reticulum II, and Triangulum II, we set constraints on the p-wave annihilation cross section in the Galaxy as an example. [ABSTRACT FROM AUTHOR]

We study the impact of fermionic dark matter (DM) on projected Higgs precision measurements at the Circular Electron Positron Collider (CEPC), including the one-loop effects on the e+e-→Zh cross section and the Higgs boson diphoton decay, as well as the tree-level effects on the Higgs boson invisible decay. As illuminating examples, we discuss two UV-complete DM models, whose dark sector contains electroweak multiplets that interact with the Higgs boson via Yukawa couplings. The CEPC sensitivity to these models and current constraints from DM detection and collider experiments are investigated. We find that there exist some parameter regions where the Higgs measurements at the CEPC will be complementary to current DM searches. [ABSTRACT FROM AUTHOR]

This paper mainly analyzes a class of piecewise nonlinear systems with fractional differential delay feedback control. The average method is used to solve the nonlinear system to obtain the amplitude-frequency relationship of the system. The analytical solution of the system can quantitatively analyze the system. At the same time, the correctness of the analytical solution of the system is verified by numerical solution. The effects of linear damping, linear stiffness and nonlinear stiffness of the system and the proportion, fractional order coefficient and fractional order number of the feedback controller on the amplitude-frequency characteristics of the system are analyzed. Finally, the dynamic analysis of the system is carried out. Taking the fractional order coefficient as the bifurcation parameter, the global characteristics of the bifurcation diagram, time history diagram and phase diagram system under different parameter perturbations are studied by power series expansion method. It is found that the system exhibits periodic motion, period doubling motion and chaos with the change of perturbation parameters. • The multi-stage nonlinear dynamic model of PD fractional-order controller • The amplitude-frequency relation equation is obtained by averaging method. • Amplitude - frequency response characteristics under different parameters • The bifurcation critical value of the model is determined. • The system presents periodic motion, period doubling motion and chaos. [ABSTRACT FROM AUTHOR]

The K0S-K0L asymmetries in the D-meson decays, induced by the interference between the Cabibbo-favored and the doubly Cabibbo-suppressed amplitudes, can help to understand the dynamics of charm decays. All possible processes of two-body nonleptonic D decays into one neutral kaon and another pseudoscalar or vector meson are considered. We study the K0S-K0L asymmetries and the branching fractions of corresponding processes in the factorization-assisted topological-amplitude approach in which significant flavor SU(3) symmetry breaking effects are included. The branching fractions of the K0L modes are predicted. It is first found that the K0S-K0L asymmetries in the D0-meson decays are shifted by the D0-D0 mixing parameter yD≃0.006, to be 0.113±0.001 for all the relevant D0 decay modes. Our results on K0S-K0L asymmetries are consistent with the current data and could be tested by experiments in the future. [ABSTRACT FROM AUTHOR]

We study a simplified scenario in the next-to-minimal supersymmetric standard model with a split electroweak spectrum, in which only the singlino and Higgsinos are light and other superpartners are decoupled. Serving as a dark matter candidate, a singlino-dominated neutralino χ01 should have either resonant annihilation effects or sizable Higgsino components to satisfy the observed relic abundance. The sensitivities of LHC searches and dark matter detection experiments are investigated. With an integrated luminosity of 30(300) fb-1, 3l+ET and 2l+ET searches at the 13 (14) TeV LHC are expected to reach up to mχ01∼150(230) GeV and mχ02,χ±1∼320(480) GeV. Near future dark matter direct and indirect detection experiments are promising to cover the parameter regions where collider searches lose their sensitivities. [ABSTRACT FROM AUTHOR]

The gamma-ray excess observed by the Fermi-LAT in the Galactic Center can be interpreted by the dark matter annihilation to bb via a light pseudoscalar in the next-to-minimal supersymmetric standard model (NMSSM). It is interesting to note that the corresponding singlet scalar is useful to achieve a strongly firstorder phase transition required by the electroweak baryogenesis. In this paper, we investigate the possibility that the NMSSM model can simultaneously accommodate these two issues. The phase transition strength can be characterized by the vacua energy gap at zero temperature and be sufficiently enhanced by the treelevel effect in the NMSSM. We find that the annihilation of singlino/Higgsino dark matter (DM) particles occurring close to the light pseudoscalar resonance is favored by the Galactic Center excess and the observed DM relic density, and some resulting regions in the parameter space with a small κ/λ and a negative Aκ can simultaneously account for a successful strongly first-order electroweak phase transition. [ABSTRACT FROM AUTHOR]

Satellite selection with genetic algorithm (GA) is proposed in this paper. With this method, selecting more than four satellites under multiple global navigation satellite systems (GNSS) can be achieved accurately and rapidly. By inserting the chromosome merit-based selection in the process of crossover and mutation, the local optimum can be avoided substantially when selecting satellites with GA. The GA parameters for satellite selection are chosen after a series of simulation experiments. Then the performance of satellite selection with GA is confirmed to be remarkable by use of the simulation experiments under different numbers of GNSS constellations and selected satellites. The selected satellites are optimum and the calculation time of satellite selection is acceptable. [ABSTRACT FROM AUTHOR]

Random slowdown process and lock-step effect, observed from real-life observation and the experiments of other researchers, were investigated in the view of the pedestrian microscopic behaviors. Due to the limited controllability, repeatability and randomness of the pedestrian experiments, a new estimating-correction cellular automaton was established to research the influence of random slowdown process and lock-step effect on the fundamental diagram. The first step of the model is to estimate the next time-step status of the neighbor cell in front of the tracked pedestrian. The second step is to correct the status and confirm the position of the tracked pedestrian in the next time-step. It is found that the random slowdown process and lock-step have significant influence on the curve configuration and the characteristic parameters, including the concavity–convexity, the inflection point, the maximum flow rate and the critical density etc. The random slowdown process reduces the utilization of the available space between two adjacent pedestrians in the longitudinal direction, especially in the region of intermediate density. However, the lock-step effect enhances the utilization of the available space, especially in the region of high density. [ABSTRACT FROM AUTHOR]

Motivated by the Galactic Center gamma-ray excess in the Fermi-LAT data, we study the signatures of a class of tau portal dark matter (DM) models where DM particles preferentially couple to tau leptons at the LHC. We consider the constraints from the DM direct detection and investigate the sensitivity of the LHC to di-tau plus missing energy signatures. We find that the LHC with a high luminosity of 3000 f b-1 can test the tau portal DM models with fermionic mediators in the mass range of 120 ~ 450 GeV. [ABSTRACT FROM AUTHOR]

Effect of spinning speed in the dynamic analysis of flexible spinning flight vehicles is emphatically considered in this paper. Taking into account gyroscopic moment and follower thrust, motion equations are formulated and then dynamic stability is analyzed. The flexible spinning flight vehicle is simplified as non-uniform rotor structure with an attached mass. Given that shear deformation influences axial displacement, Timoshenko beam model is adopted by considering the effect of gyroscopic moment and follower thrust. Finally motion equations are established based on the finite element method to analyze impacts of factors such as speed, shear stiffness and attached mass, etc. on the stability of the system. A new phenomenon of modal coupling between rigid modal and elastic modal in the system of spinning flight vehicles is discovered under the influence of spinning speed. Results show that shear deformation has great influence on the critical thrust when shear stiffness value is small; magnitude and position of attached mass has certain impacts on critical thrust and instability region; bending modal and rigid modal of the non-uniform rotor system are generally induced to merge to a coupled modal, thus resulting in dynamic instability. [ABSTRACT FROM AUTHOR]

We explore the mono-Z signature for dark matter searches at future high energy e+e- colliders. In the context of effective field theory, we consider two kinds of contact operators describing dark matter interactions with electroweak gauge bosons and with electron/positron, respectively. For five benchmark models, we propose kinematic cuts to distinguish signals from backgrounds for both charged leptonic and hadronic decay modes of the Z boson. We also present the experimental sensitivity to cutoff scales of effective operators and compare it with that of the Fermi-LAT indirect search and demonstrate the gains in significance for the several configurations of polarized beams. [ABSTRACT FROM AUTHOR]

We investigate the di-Higgs events through ZH-pair production at the CERN Large Hadron Collider including the pure next-to-leading order (NLO) QCD correction and the gg-fusion contribution in the framework of the littlest Higgs model with T parity. We employ the diagram subtraction scheme in the QCD NLO calculations to avoid double counting and keep the convergence of the perturbative QCD description for the ZH-pair production. We investigate the dependence of the leading order and QCD corrected integrated cross sections on the renormalization/factorization scale, and find that the total QCD corrections slightly reduce the scale uncertainty in the plotted range. By considering the subsequent decays of the intermediately produced ZH bosons and adopting the exclusive four-b-jet event selection criterion, the QCD correction provides considerable enhancement of the kinematic distributions for final decay products. We find that it is possible to select the signature of the ZH-pair production from possible standard model background by taking proper kinematic cuts. [ABSTRACT FROM AUTHOR]

The high-resolution x-ray-scattering technique is used to study the elastic scattering of atoms and molecules in the gas phase. The elastic squared form factor, which is the square of the Fourier transformation of the electron density distribution in position space and reveals the pure electronic structure of atoms and molecules in the ground state, of molecular hydrogen is measured at an incident photon energy of about 9889 eV and an energy resolution of about 70 meV. Although it is generally thought that the x-ray-scattering technique is identical to high-energy electron scattering, at least for elastic scattering these two techniques have an apparent difference, i.e., the pure electronic structure of a molecule in the ground state can be determined by x-ray scattering while it cannot be obtained by the high-energy electron impact method due to the interference between the scattering of separate nuclei and of the electrons in the target. The present experimental results match the theoretical calculations very well, which demonstrates that high-resolution x-ray scattering is a powerful tool to study the electronic structure of atoms and molecules in the ground state. [ABSTRACT FROM AUTHOR]

Five new compounds, including one new xanthone, 1-hydroxy-5-methoxyxanthone 6-O-β-D-glucopyranoside (1), one new lignan, 3-(β-D-glucopyranosyloxymethyl)-2-(4-hydroxy-3-methoxyphenyl)-5-(3-acetoxypropyl)-7-methoxy-(2R,3S)-dihydrobenzofuran (2), and three new γ-pyrones, japonicumone A 4'-O-β-D-glucopyranoside (3), japonicumone B 3'-O-β-D-glucopyranoside (4), and japonicumone B 4'-O-β-D-glucopyranoside (5), together with eight known compounds (6-13) were isolated from the whole plants of Arenaria serpyllifolia. Their structures were elucidated on the basis of extensive spectroscopic analysis (UV, IR, HRESIMS, 1D- and 2D-NMR, and CD) as well as chemical methods. The isolated compounds were evaluated for their inhibitory effects on nitric oxide production in lipopolysaccharide-activated RAW 264.7 macrophages. Compounds 1-5, sacranoside A (9), and pedunculoside (13) showed potential nitric oxide inhibitory activities with IC50 values ranging from 14.92 µM to 52.23 µM. [ABSTRACT FROM AUTHOR]