Miracle-dz/UniFAR-FTUs huggingface dataset:
Love-wave excitation due to the interaction between a propagating ocean wave and the sea-bottom topography

SUMMARY This study formulates Love-wave excitation in terms of the interaction between a propagating ocean wave and the sea-bottom topography. By assuming a Fraunhofer diffraction range, or far-field approximation, I theoretically derive an equivalent point force for the Love-wave excitation. The equivalent point force acts in the same direction as the propagation direction of the ocean wave. The excited Love wave has a radiation pattern characterized by sin θ, where θ is the angle between the propagation directions of the Love and ocean waves. The efficiency of the excitation is then investigated by employing both deterministic and stochastic models for sea-bottom topography. When a seamount given by a Gaussian function is used as a deterministic model, the equivalent point force has a narrow peak against the wavenumber of the ocean wave; a strong interaction occurs at λ= 2.2d, where λ is the ocean-wave wavelength and d is the characteristic scale of the seamount. On the other hand, when randomly fluctuating sea-bottom topography characterized by a power-law spectrum is used, the interaction can occur over a wide range of the ocean wave wavelength.
Dust Emission from L1641N: An Optically Thick Circumstellar Disk?

We have obtained high angular resolution (1''-3'') continuum maps of the young stellar object L1641N (IRAS 05338-0624) at 2.0 mm, 7.0 mm, and 1.3 cm. The source positions at the three wavelengths coincide with a very red near-IR source detectable only at λ > 4 μm. The source is unresolved at 1.3 cm with a 1'' beam (or 250 AU in radius). When combined with flux densities at other wavelengths, we find that the spectral energy distribution at mm wavelengths can be well fit by a power law with a spectral index of 2.1 ± 0.2, and that the distribution between 2.0 mm and 6 cm can be well fit by a combination of the dust emission and optically thin free-free emission. Among several possible interpretations of the observed continuum spectrum, we favor optically thick dust emission from within 250 AU of L1641N, and the most probable origin of such emission is a circumstellar disk around the young star. We also discuss the physical properties of the optically thick disk.
Minimizing risk models in Markov decision processes with policies depending on target values

Abstract This paper studies the minimizing risk problems in Markov decision processes with countable state space and reward set. The objective is to find a policy which minimizes the probability (risk) that the total discounted rewards do not exceed a specified value (target). In this sort of model, the decision made by the decision maker depends not only on system's states, but also on his target values. By introducing the decision-maker's state, we formulate a framework for minimizing risk models. The policies discussed depend on target values and the rewards may be arbitrary real numbers. For the finite horizon model, the main results obtained are: (i) The optimal value functions are distribution functions of the target, (ii) there exists an optimal deterministic Markov policy, and (iii) a policy is optimal if and only if at each realizable state it always takes optimal action. In addition, we obtain a sufficient condition and a necessary condition for the existence of finite horizon optimal policy independent of targets and we give an algorithm computing finite horizon optimal policies and optimal value functions. For an infinite horizon model, we establish the optimality equation and we obtain the structure property of optimal policy. We prove that the optimal value function is a distribution function of target and we present a new approximation formula which is the generalization of the nonnegative rewards cases. An example which illustrates the mistakes of previous literature shows that the existence of optimal policy has not been proved really. In this paper, we give an existence condition, which is a sufficient and necessary condition for the existence of an infinite horizon optimal policy independent of targets, and we point out that whether there exists an optimal policy remains an open problem in the general case.
Moduli of Tango Structures and Dormant Miura Opers

The purpose of the present paper is to develop the theory of (pre-)Tango structures and (dormant generic) Miura $\mathfrak{g}$-opers (for a semisimple Lie algebra $\mathfrak{g}$) defined on pointed stable curves in positive characteristic. A (pre-)Tango structure is a certain line bundle of an algebraic curve in positive characteristic, which gives some pathological (relative to zero characteristic) phenomena. In the present paper, we construct the moduli spaces of (pre-)Tango structures and (dormant generic) Miura $\mathfrak{g}$-opers respectively, and prove certain properties of them. One of the main results of the present paper states that there exists a bijective correspondence between the (pre-)Tango structures (of prescribed monodromy) and the dormant generic Miura $\mathfrak{s} \mathfrak{l}_2$-opers (of prescribed exponent). By means of this correspondence, we achieve a detailed understanding of the moduli stack of (pre-)Tango structures. As an application, we construct a family of algebraic surfaces in positive characteristic parametrized by a higher dimensional base space whose fibers are pairwise non-isomorphic and violate the Kodaira vanishing theorem.
Analysis of some splitting schemes for the stochastic Allen-Cahn equation

We introduce and analyze an explicit time discretization scheme for the one-dimensional stochastic Allen-Cahn, driven by space-time white noise. The scheme is based on a splitting strategy, and uses the exact solution for the nonlinear term contribution. We first prove boundedness of moments of the numerical solution. We then prove strong convergence results: first, \begin{document}$L^2(\Omega)$\end{document} -convergence of order almost \begin{document}$1/4$\end{document} , localized on an event of arbitrarily large probability, then convergence in probability of order almost \begin{document}$1/4$\end{document} . The theoretical analysis is supported by numerical experiments, concerning strong and weak orders of convergence.
Adults Born Small for Gestational Age at Term Have Thinner Peripapillary Retinal Nerve Fiber Layers Than Controls

Purpose Prenatal growth restriction is associated with impaired neurodevelopment in childhood. This study investigated the effects of being born small for gestational age (SGA) on peripapillary retinal nerve fiber layer (pRNFL) thickness in adults born at term. Methods A retrospective cohort study was conducted with a prospective ophthalmologic examination of participants born at full-term (gestational age ≥37 weeks) between 1969 and 2002. All participants were examined with spectral-domain optical coherence tomography and grouped according to their birth weight in correlation to gestational age as former moderate (birth weight (BW) percentile 3rd to <10th) and severe SGA (<3rd percentile), normal (10th-90th percentile, AGA), and moderately (>90th to 97th percentile) and severely (>97th percentile) large for gestational age (LGA) adults (18 to 52 years). Results Overall, 547 eyes of 285 individuals (age 29.9±9.4 years, 151 females) born at term were included. Multivariable regression analyses revealed a strong association between a lower global pRNFL thickness in the severe SGA (B=−8.99 [95%-CI: −12.68; −5.30] µm; p<0.001) and in the moderate SGA groups (B=−6.40 [95%-CI: −10.29; −2.50] µm; p=0.001) compared to the reference AGA group. Conclusion Our results indicate that restricted fetal growth affects neurologic tissue development of the optic nerve head, particularly in individuals born severely SGA at term. This indicates that fetal growth restriction may exert disturbances in the development of neurologic tissue, which persists in adulthood.
Micromechanical Aspects of Isotropic Granular Assemblies With Linear Contact Interactions

The paper presents a micromechanical analysis of plane granular assemblies of discs with a range of diameters, and interacting according to linear contact force-interparticle compliance relationships. Contacts are assumed to be fixed and indestructible. Macroscopically, the system is described in terms of a two-dimensional analogue of generalized Hooke’s law. Explicit expressions for elastic constants in terms of microstructure are derived for dense isotropic assemblies. It is shown that Poisson’s ratio for dense systems depends on the ratio of tangential to normal contact stiffnesses. The derived expression for Poisson’s ratio is verified by numerically simulating plane assemblies comprising 1000 particles. The effect of density on Poisson’s ratio is investigated using numerical simulations. The theory of dense plane systems is extended to dense three-dimensional systems comprising spheres. Finally, it is shown that Poisson’s result ν=1/4 is recovered for spherical particles with central interactions.
Linear and nonlinear interactions of an electron beam with oblique whistler and electrostatic waves in the magnetosphere

Both linear and nonlinear interactions between oblique whistler, electrostatic, quasi-upper hybrid mode waves and an electron beam are studied by linear analyses and electromagnetic particle simulations. In addition to a background cold plasma, we assumed a hot electron beam drifting along a static magnetic field (Bo). Growth rates of the oblique whistler, oblique electrostatic, and quasi-upper hybrid instabilities were first calculated. We found that there are four kinds of unstable mode waves for parallel and oblique propagations. They are the electromagnetic whistler mode wave (WW1), the electrostatic whistler mode wave (WW2), the electrostatic mode wave (ESW), and the quasi-upper hybrid mode wave (UHW). When the angle θ between the wave vector k and Bo is small enough (≤10°), the electrostatic instability is dominant compared with the whistler mode instability. When θ is around 30°, the growth rates of whistler (both electrostatic and electromagnetic) mode waves and electrostatic mode waves are of the same order. When θ increases to 60°, the WW2 mode will be the most unstable mode wave. For a very large θ, (∼ 80°), the WW2 instability still has positive growth rates, and the UHW instability begins to have positive growth rates. Electromagnetic particle simulations were performed for parallel and three oblique cases, θ = 0°, 30°, 60° and 80°. When θ = 0°, whistler mode waves can hardly grow from the thermal fluctuation level because the electron beam which is supposed to provide free energy to the whistler mode waves is quickly diffused in the velocity space by much faster growing ESW. The ESW can lead to a secondary electrostatic instability. With θ = 30°, both electrostatic and whistler mode waves grow simultaneously. Also, the electrons diffused by the whistler mode instability to higher υ∥ velocity regions can lead to a secondary electrostatic instability. When θ is 60°, diffusion of the electron beam is controlled mainly by the WW2 instability. For θ = 80°, both WW2 and UHW grow despite their small growth rates. The simulations agree with linear analyses on the ESW growth rate for θ = 0°, but from our simulation data, growth rates of oblique whistler mode, electrostatic mode and quasi-upper hybrid mode waves are usually smaller than those predicted by linear analyses. The electrostatic and whistler mode instabilities affect each other through their interactions with the electron beam. While the most intense ESW is generated for parallel propagation, the most intense whistler mode wave is observed at an oblique direction. Modulations between different electrostatic waves are found for θ = 0° after the electric field reaches its saturation level. Modulations between whistler waves (θ = 60°,80°) are also found while their magnetic fields increase nonlinearly and reach their saturation levels. A possible mechanism is proposed to explain the satellite observations of whistler mode chorus and accompanied electrostatic waves, whose amplitudes are sometimes modulated at the chorus frequency.
A NOTE ON THE POWER OF BOOTSTRAP UNIT ROOT TESTS

In this note we consider the asymptotic power functions of some bootstrap unit root tests under local alternatives and show that they are in fact the same as for ordinary unit root tests. This is regardless of whether the differences of the observations, i.e., the so-called restricted residuals, or the ordinary least squares residuals are used to construct the resampled observations. We also consider models containing a constant and a linear trend and the DF-GLS tests proposed by Elliott, Rothenberg, and Stock (1996, Econometrica 64, 813–836). A small Monte Carlo experiment is included.I thank the associate editor, Bruce E. Hansen, and three anonymous referees for very constructive comments on the previous versions of the manuscript.
The invariant classification of conformally flat pure radiation spacetimes

We study conformally flat pure radiation spacetimes by means of their invariant classifications and show that no such spacetime requires higher than the fourth covariant derivative of the Riemann tensor in its invariant classification. Additional side results that we obtain are as follows. The Edgar - Ludwig metric for conformally flat pure radiation is shown to be a true generalization of the Wils metric; the subclass of the Edgar - Ludwig spacetimes which admit exactly one Killing vector is identified, generalizing Koutras's G1 subclass of the Wils metric; it is shown that the Edgar - Ludwig spacetimes with no Killing vectors can further be split into three discrete subsets, depending on the Cartan invariant where the fourth essential coordinate is found.
Effective thermal conductivity of nanofluids: the effects of microstructure

We examine numerically the effects of particle–fluid thermal conductivity ratio, particle volume fraction, particle size distribution and particle aggregation on macroscale thermal properties for seven kinds of two-dimensional nanofluids. The results show that the radius of gyration and the non-dimensional particle–fluid interfacial area are two important parameters in characterizing the geometrical structure of nanoparticles. A non-uniform particle size is found to be unfavourable for the conductivity enhancement, while particle-aggregation benefits the enhancement especially when the radius of gyration of aggregates is large. Without considering the interfacial thermal resistance, a larger non-dimensional particle–fluid interfacial area between the base fluid and the nanoparticles is also desirable for enhancing thermal conductivity. The nanofluids with nanoparticles of connected cross-shape show a much higher (lower) effective thermal conductivity when the particle–fluid conductivity ratio is larger (smaller) than 1.
ORIENTED MEASURES WITH CONTINUOUS DENSITIES AND THE BANG{BANG PRINCIPLE

Abstract We introduce the notion of an oriented measure. For such a measure μ, given ν in L 1 ([ a , b ]), 0 E ⊂ [ a , b ] whose characteristic functions have less than n discontinuity points and such that ∫ ν d μ = μ( E ). Given a solution x to the control problem L ( x ) = x ( n ) + a n − 1 ( t ) x ( n − 1) + … + a 1 ( t ) x ′ + a 0 ( t ) x ∈ [φ 1 , φ 2 ] there exist two bang-bang solutions y , z having a contact of order n with x at a and b such that y ≤ x ≤ z . Reachable sets of bang-bang constrained solutions are convex; an application to the calculus of variations yields a density result.
3d Mirror Symmetry and Elliptic Stable Envelopes

We consider a pair of quiver varieties (X;X') related by 3d mirror symmetry, where X =T*Gr(k,n) is the cotangent bundle of the Grassmannian of k-planes of n-dimensional space. We give formulas for the elliptic stable envelopes on both sides. We show an existence of an equivariant elliptic cohomology class on X $\times$ X' (the Mother function) whose restrictions to X and X' are the elliptic stable envelopes of those varieties. This implies, that the restriction matrices of the elliptic stable envelopes for X and X' are equal after transposition and identification of the equivariant parameters on one side with the Kahler parameters on the dual side.
Generation and propagation of attosecond pulses in He gas with sub-10-fs driver pulses

The generation and propagation of attosecond pulses in He gas by using intense sub-10-fs driver pulse are numerically investigated. It is shown that a single attosecond pulse can be generated by Fourier synthesis of selected successive harmonics either in the cutoff or in the plateau regions of spectrum. In both cases the maximal electric field intensity and the duration of the attosecond pulse can be controlled by appropriately choosing the propagation length.
Influence of the Pacific Decadal Oscillation on Winter Precipitation and Drought during Years of Neutral ENSO in the Western United States

Abstract The influence of the Pacific decadal oscillation (PDO) on important hydroclimatic variables during years of neutral ENSO for 84 climate divisions in the western United States is analyzed from 1925 to 1998. When the 34 neutral ENSO years are split by cold (12 yr) and warm (22 yr) PDOs, the resulting winter precipitation patterns are spatially similar to those that occur during years of La Nina–cold PDO and, to a lesser extent, years of El Nino–warm PDO, respectively, although the characteristic ENSO dipole is not evident. The PDO influence is similar when the winter Palmer drought severity index is analyzed, although the core area of influence moves from the Southwest to the northern Rockies. Correlations between Nino-3.4 SSTs and the hydroclimatic variables reverse sign when the neutral ENSO years are split by PDO phase. The greatest difference between correlations occurs in the characteristic dipole between the Pacific Northwest and the desert Southwest. Since seasonal forecast guidance based on.
New Classes of Facets of Cut Polytope and Tightness of I_{mm22} Bell Inequalities

The Grishukhin inequality Gr_7 is a facet of CutP_7, the cut polytope on seven points, which is ``sporadic'' in the sense that its proper generalization has not been known. In this paper, we extend Gr_7 to an inequality I(G,H) valid for CutP_{n+1} where G and H are graphs with n nodes satisfying certain conditions, and prove a necessary and sufficient condition for I(G,H) to be a facet. This result combined with the triangular elimination theorem of Avis, Imai, Ito and Sasaki settles Collins and Gisin's conjecture in quantum theory affirmatively: the I_{mm22} Bell inequality is a facet of the correlation polytope CorP(K_{m,m}) of the complete bipartite graph K_{m,m} for all m>=1. We also extend the Gr_8 facet inequality of CutP_8 to an inequality I'(G,H,C) valid for CutP_{n+2}, and provide a sufficient condition for I'(G,H,C) to be a facet.
Analytical model for regular dense arrays of planar dipole scatterers.

An analytical boundary condition for modeling the electromagnetic properties of planar regular dense arrays of dipole particles for oblique incidence of plane waves is developed. The regular array is assumed to be dense which means that the dipole particles are close to each other. The interaction between the dipole particles is taken into account by interaction constant. The expression for the interaction constant is written in analytical form and is used for developing a transmission-line model for arrays of planar dipole scatterers. The regular dense array is modeled as a shunt impedance which is different for TM and TE polarizations.
C^m-extension of subharmonic functions

Given and any (Jordan) -domain in , we prove that any function of class that is subharmonic in can be extended to a function of class that is subharmonic on the whole and give an estimate of the -norm of its gradient. The corresponding assertion for is false even for discs. These results also hold for balls in , . We also obtain some corollaries, including the corresponding assertions on the -extension of subharmonic functions.
Lobbying Game between the Government with Private Information and the Lobbyist

This paper presents an examination of a lobbying game between a government with informational superiority and a special interest group (SIG), which is a lobbyist. This informational superiority of the government allows the application of an analytical method of ordinary contract theory in this game. Results of these analyses show that, for a SIG whose population is sufficiently small, although the government has informational superiority to the SIG, the government is unable to prevent the SIG from distorting policy excessively by endowing a political contribution to the government. However, for a SIG whose population is sufficiently large, the government’s informational superiority can stanch the SIG inducement of a larger policy by endowing a political contribution to the government. In this case, government disclosure is not always socially desirable.
EFFECTS OF FREE-END CONDITION ON END-CELL-INDUCED VIBRATION

Abstract Wind tunnel experiments were conducted to investigate the characteristics of the transverse-wind vibration of a pivoted circular cylinder. It is confirmed that a vibration, which is similar to the vortex-induced vibration, occurs at a wind speed higher than the threshold wind speed for the vortex-induced vibration. Special attention is paid to the cause of that vibration. In this study, that vibration is called as “end-cell-induced vibration (ECIV)”, and the mechanism of ECIV is investigated. The measurement of the wind velocity fluctuation behind the model at various heights indicates that vortices whose frequency is much lower than the Karman vortex shedding frequency are generated around the free end of the model. This vortex is called “tip-associated vortex” in this study. ECIV occurred at the wind speed where the frequency of these vortices coincides with the natural frequency of the model. Therefore, ECIV is thought to be caused by tip-associated vortex shedding. Furthermore, based on the conjecture which the three-dimensional flow around the free-end affects the generation of the tip-associated vortices, a thin circular disk is attached to the model top and its diameter is varied. The effects of the circular disk on ECIV and on the generation of the tip-associated vortices are studied experimentally.
High frequency carbon nanomechanical resonators embedded with carbon nanotube stiffening layers

We present batch-fabricated carbon-based nanomechanical resonators which are laminated by a pyrolyzed carbon layer and single-walled carbon-nanotube network (C/CNT resonators). The embedded CNT layers simultaneously enhance the electrical conductivity (∼160-fold) and mechanical stiffness (10% higher Young’s modulus) compared to nonstiffened carbon-only resonators. Dynamic behaviors of the fabricated C/CNT and carbon-only resonators, including fundamental frequency, Q-factor, and frequency tuning characteristics show comparable performance to the silicon based resonators.
Dendroidal Sets

We introduce the concept of a dendroidal set. This is a generalization of the notion of a simplicial set, specially suited to the study of (coloured) operads in the context of homotopy theory. We define a category of trees, which extends the category  used in simplicial sets, whose presheaf category is the category of dendroidal sets. We show that there is a closed monoidal structure on dendroidal sets which is closely related to the Boardman–Vogt tensor product of (coloured) operads. Furthermore, we show that each (coloured) operad in a suitable model category has a coherent homotopy nerve which is a dendroidal set, extending another construction of Boardman and Vogt. We also define a notion of an inner Kan dendroidal set, which is closely related to simplicial Kan complexes. Finally, we briefly indicate the theory of dendroidal objects in more general monoidal categories, and outline several of the applications and further theory of dendroidal sets.