Numerical calculations show that acoustic ray paths in a weakly range‐dependent deterministic ocean model exhibit chaotic behavior, is, have an exponentially sensitive dependence on initial conditions. Since the equations define nonautonomous Hamiltonian system with one degree of freedom, these results may be understood terms recent advances classical chaos. The structure general suggests trajectories will present all types linear wave motion geophysics when variables do not separate, as...

Recent techniques have been successful in reconstructing surfaces as level sets of learned functions (such signed distance fields) parameterized by deep neural networks. Many these methods, however, learn only closed and are unable to reconstruct shapes with boundary curves. We propose a hybrid shape representation that combines explicit curves implicit interiors. Using machinery from geometric measure theory, we parameterize currents using networks use stochastic gradient descent solve...

The channel technique has been successfully applied to measurement of the properties cleaved germanium surfaces. A clean surface is highly $p$ type with Fermi level near valence band at surface. This brought about by acceptor-like states close edge a density least 1.5\ifmmode\times\else\texttimes\fi{}${10}^{12}$/${\mathrm{cm}}^{2}$. these low-lying decreases when exposed oxygen. comparison made between results on surfaces and cleaned ion bombardment.

Received 11 November 1960DOI:https://doi.org/10.1103/PhysRevLett.6.170©1961 American Physical Society

Field-guided parameterization methods have proven effective for quad meshing of surfaces; these compute smooth cross fields to guide the process and then integrate construct a discrete mesh. A key challenge in extending three dimensions, however, is representation field values. Whereas can be represented by tangent vector that form linear space, 3D analog—an octahedral frame field—takes values nonlinear manifold. In this work, we describe space frames language differential algebraic...

Sub‐sea floor hydrothermal convection systems discharge as plumes from point sources and seepage the ocean bottom. The originate clear, 150–400°C solutions that vent mineralized chimneys; precipitate dissolved metals particles to form black or white smokers they turbulently mix with ambient seawater; buoyantly rise hundreds of meters a level neutral density where spread laterally. discharges networks fractures at rock‐water interface diffuse flow, lower temperatures, metal contents, buoyancy...

We report the first observations based on acoustic imaging of large‐scale structure and time variability buoyant plumes emanating from black smoker‐type seafloor hot springs. Three‐dimensional plume reconstructions were made a digital data set backscattering information recorded prototype submersible‐mounted sonar system. The images two adjacent smokers depict volume show zones flow organization (meters to tens meters) in lower 40 m plumes. coalesce, bend prevailing current, exhibit...

This article offers an interim assessment of the Microelectronics and Computer Technology Corporation (MCC). It approaches this task from three perspectives: (1) a descriptive review MCC's origins development National Cooperative Research Act 1984, under which MCC qualified for limited exemption antitrust laws purpose collaboration, as defined, in research development; (2) empirical study what is new distinctive about MCC; (3) its future prospects private corporation de facto instrument U.S....

A survey was mailed to 2000 randomly selected students at four campuses in a southern mid-western state. The examined college students' knowledge, attitudes and beliefs regarding AIDS, their sexual activity, safer sex practices, prosocial actions they would be willing take preferred channels of communication for additional information about AIDS Related Complex (ARC). results generally indicated that were well informed the common methods transmission but showed lack correct issues such as by...

Geometry processing presents a variety of difficult numerical problems, each seeming to require its own tailored solution. This breadth is largely due the expansive list geometric primitives , e.g., splines, triangles, and hexahedra, joined with an ever-expanding objectives one might want achieve them. With recent increase in attention toward higher-order surfaces we can expect challenges porting existing solutions that work on triangle meshes these more complex geometry types. In this...

We explore the possibility of using active sonar techniques to acoustically image high-temperature ‘‘black smoker’’ hydrothermal plumes. examine recent images a vent field at 11°N on East Pacific Rise obtained from DSRV Alvin which may show presence For fields estimates are minimum detectable concentration precipitates as function range between and plume boundary. These compared with measured concentrations. Some anticipated advantages acoustic imaging discussed. conclude that have potential...

A rigorous bound is calculated for the hadronic contribution to anomalous magnetic moment of muon. The free phenomenological input; only analyticity pion electromagnetic form factor assumed. An improved then by using experimental value radius as input.

The Florida Current, which flows through the Straits of Florida, transports a significant fraction heat must be transferred from low to high latitudes in order for earth remain thermal balance. While ocean acoustic tomography is an atttactive candidate monitoring this transport, its use dependent on being able identify individual ray paths. All published investigations have been concerned with deep‐ocean propagation where experience has shown that paths can identified. Propagation quite...

This study compared the caloric expenditure of 30 consecutive minutes (30 minute) moderate intensity walking with 3 intermittent 10-minute bouts (3 x 10 minutes) in healthy, unfit men (40-49 years). Screening consisted VO(2)max testing, which was measured using Balke graded exercise test. Criteria for participation this included a less than 33.8 ml.kg(-1).min(-1) (<25th percentile cardiorespiratory fitness). Twenty participated study. Testing 4 trials minimum 5 days between each trial. The...

We discuss two aspects of the general problem sound propagation in an ocean characterized by a range-dependent profile. first consider normal-mode formalism for describing situation which eikonal approximation can be applied horizontal plane. The difficulty with this approach is shown to ordering geometric optics path-length parameter due mode coupling. By example we indicate how overcome. then use approximations make up parabolic equation method. derived assuming plane and degenerate...

The Drell-Hearn sum rule for the nucleon anomalous magnetic moment is derived by using light-cone commutator + components of current. ${q}^{2}=0$ limits several other rules are also from ++ commutator. These have been previously but only a more model-dependent

A comprehensive framework is developed for calculating the intensity received by a monostatic sonar system due to backscattering from cloud of nonspherical particles suspended in ocean. The can consist different types having arbitrary shapes, volume distributions, and orientations, as well an overall mass density that varies spatially within cloud. In Rayleigh region it possible average over particle orientation exactly. averaged backscattered depends on shape through eigenvalues tensor can,...

Abstract The validity of trilinear hexahedral (hex) mesh elements is a prerequisite for many applications hex meshes, such as finite element analysis. A commonly used check evaluates quality on the corners parameter domain each hex, an insufficient condition that neglects invalidity elsewhere in element, but straightforward to compute. Hex optimizations using this criterion suffer by being unable detect invalidities reliably, let alone fix them. We rectify these challenges leveraging...