61 research outputs found
Electron Oscillation-Based Mono-Color Gamma-Ray Source
Production of artificial gamma-ray source usually is a conception belonging to the category of experimental nuclear physics. Nuclear physicists achieve this goal through utilizing/manipulating nucleons, such as proton and neutron. Low-energy electrons are often taken as âby-productsâ when preparing these nucleons by ionizing atoms, molecules and solids, and high-energy electrons or
β
rays are taken as âwastageâ generated in nuclear reaction. Utilization of those âby-productsâ has not won sufficient attention from the nuclear physics community. In this chapter, we point out a potential, valuable utilization of those âby-products.â Based on a universal principle of achieving powerful mono-color radiation source, we propose how to set up an efficient powerful electron-based gamma-ray source through available solid-state components/elements. Larger charge-to-mass ratio of an electron warrants the advantage of electron-based gamma-ray source over its nucleon-based counterpart. Our technique offers a more efficient way of manipulating nuclear matter through its characteristic EM stimulus. It can warrant sufficient dose/brightness/intensity and hence an efficient manipulation of nuclear matter. Especially, the manipulation of a nucleus is not at the cost of destroying many nuclei to generate a desired tool, that is, gamma ray with sufficient intensity, for achieving this goal. This fundamentally warrants a practical manipulation of more nuclei at desirable number
Equivalent Nanocircuit Theory and Its Applications
A new methodology termed as equivalent nanocircuit (EN) theory is briefly introduced, and its recent important progress in designing metaâmaterial devices with peculiar characteristics in optical or infrared frequency domain is reviewed. Three representative ENâbased designs of infrared window metaâmaterials, such as Butterworth filter, metalâinsulatorâmetal absorber and designâsimplified TCOâbased superâflat absorber, are demonstrated. All these progresses clearly indicate that the EN theory provides an inspiring advancement on the way of designing more complicated metaâdevices
A modified FDTD algorithm for processing ultra-wide-band response
Finite-difference time-domain (FDTD) is an effective algorithm for resolving
Maxwell equations directly in time domain. Although FDTD has obtained
sufficient development, there still exists some improvement space for it, such
as ultra-wide-band response and frequency-dependent nonlinearity. In order to
resolve these troubles, a modified version of FDTD called complex-field
frequency-decomposition (CFFD) FDTD method is introduced, in which the
complex-field is adopted to eliminate pseudo-frequency components when
computing nonlinearity and the frequency-decomposition is adopted to transform
an ultra-wide-band response into a series of narrow-band responses when
computing the interaction of ultra-short pulse with matters. Its successful
applications in several typical situations and comparison with other methods
sufficiently verify the uniqueness and superiority in processing
ultra-wide-band response and frequency-dependent nonlinearity.Comment: 8 figure
MVICS: a repository and search tool towards holistic semantic-based precise component selection.
Driven by the continuous expansions of software applications and the increases in component varieties and sizes, the so-called component mismatch problem has become a more severe hurdle for component selection and integration. Although many component repositories and search tools have been proposed, so far there is no satisfactory solution which simultaneously achieves the following goals: automated, semantic-based, and precise. This paper presents a novel component repository and associated search tool which implements holistic semantic-based and adaptation-aware component specification and retrieval. The repository and tool is based on a Multiple-View and Interrelated Component Specification ontology model (MVICS), which has a smooth integration with domain related software system ontologies. The MVICS provides a formally defined and ontology-based architecture to specify components automatically in a spectrum of perspectives. The integration enhances the function and application scope of the MVICS model by bringing domain semantics into component specification and retrieval. The repository and search tool contributes to the current state of the art with four unique features: ontology-based component specification mechanism, semantic-based component retrieval method, adaptive component matching, and a comprehensive result component profile. The repository and tool has been widely tested and evaluated via its online version and follow-on survey reports, which concluded that they are effective for avoiding the component mismatch problem and is promising for industrial use
TDLE: 2-D LiDAR Exploration With Hierarchical Planning Using Regional Division
Exploration systems are critical for enhancing the autonomy of robots. Due to
the unpredictability of the future planning space, existing methods either
adopt an inefficient greedy strategy or require a lot of resources to obtain a
global solution. In this work, we address the challenge of obtaining global
exploration routes with minimal computing resources. A hierarchical planning
framework dynamically divides the planning space into subregions and arranges
their orders to provide global guidance for exploration. Indicators that are
compatible with the subregion order are used to choose specific exploration
targets, thereby considering estimates of spatial structure and extending the
planning space to unknown regions. Extensive simulations and field tests
demonstrate the efficacy of our method in comparison to existing 2D LiDAR-based
approaches. Our code has been made public for further investigation.Comment: Accepted in IEEE International Conference on Automation Science and
Engineering (CASE) 202
MVICS: a repository and search tool towards holistic semantic-based precise component selection.
Driven by the continuous expansions of software applications and the increases in component varieties and sizes, the so-called component mismatch problem has become a more severe hurdle for component selection and integration. Although many component repositories and search tools have been proposed, so far there is no satisfactory solution which simultaneously achieves the following goals: automated, semantic-based, and precise. This paper presents a novel component repository and associated search tool which implements holistic semantic-based and adaptation-aware component specification and retrieval. The repository and tool is based on a Multiple-View and Interrelated Component Specification ontology model (MVICS), which has a smooth integration with domain related software system ontologies. The MVICS provides a formally defined and ontology-based architecture to specify components automatically in a spectrum of perspectives. The integration enhances the function and application scope of the MVICS model by bringing domain semantics into component specification and retrieval. The repository and search tool contributes to the current state of the art with four unique features: ontology-based component specification mechanism, semantic-based component retrieval method, adaptive component matching, and a comprehensive result component profile. The repository and tool has been widely tested and evaluated via its online version and follow-on survey reports, which concluded that they are effective for avoiding the component mismatch problem and is promising for industrial use
Origin of Unexpected Low Energy Structure in Photoelectron Spectra Induced by Mid-Infrared Strong Laser Fields
Using a semiclassical model which incorporates tunneling and Coulomb field
effects, the origin of the unexpected low-energy structure (LES) in
above-threshold ionization spectrum observed in recent experiments [C. I. Blaga
et al., Nature Phys. {\bf 5}, 335 (2009) and W. Quanet al., Phys. Rev. Lett.
{\bf 103}, 093001 (2009)] is identified. We show that the LES arises due to an
interplay between multiple forward scattering of an ionized electron and the
electron momentum disturbance by the Coulomb field immediately after the
ionization. The multiple forward scattering is mainly responsible for the
appearance of LES, while the initial disturbance mainly determines the position
of the LES peaks. The scaling laws for the LES parameters, such as the contrast
ratio and the maximal energy, versus the laser intensity and wavelength are
deduced
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