• Title, Summary, Keyword: Single particle states

Search Result 16, Processing Time 0.038 seconds

Various Quantum Ring Structures: Similarity and diversity

  • Park, Dae-Han;Kim, Nammee
    • Applied Science and Convergence Technology
    • /
    • v.25 no.2
    • /
    • pp.36-41
    • /
    • 2016
  • Similarity and diversity of various quantum ring structures are investigated by classifying energy dispersions of three different structures: an electrostatic quantum ring, a magnetic quantum ring, and a magnetic-electric quantum ring. The wave functions and the eigenenergies of a single electron in the quantum ring structures are calculated by solving the Schrdinger equation without any electron-electron interaction. Magnetoconductance is studied by calculating a two-terminal conductance while taking into account the backscattering via the resonance through the states of the quantum rings at the center of a quasi-one dimensional conductor. It is found that the energy spectra for the various quantum ring structures are sensitive to additional electrostatic potentials as well as to the effects of a nonuniform magnetic field. There are also characteristics of similarity and diversity in the energy dispersions and in the single-channel magnetoconductance.

Formulation of Statistical Mechanics in Terms of Information Theory

  • Kim, Sangrak
    • New Physics: Sae Mulli
    • /
    • v.67 no.2
    • /
    • pp.226-231
    • /
    • 2017
  • We present a new formulation of statistical mechanics based on information theory. Starting from completely independent systems, we increase the level of dependency between the systems step-by-step and extend the dimensionality of the system and the number of particles. The number of accessible states for a single particle in occupying the states plays a central role in the particle statistics of many identical particles. The corresponding expressions for the Shannon entropy of many identical particles are naturally derived from this building block for the cases of indistinguishable/distinguishable and/or interacting/noninteracting systems. We employ the concepts of coarse-graining and mutual information. The counting factor N! can be regarded as a coarse-graining factor. The interaction between particles implies mutual information between locations of the particles.

Internal Mixing of Pollutants for Submicron Particles Observed during Springtime in Japan

  • Matsumoto, Jun;Narukawa, Masahiro;Takahashi, Kenshi;Matsumi, Yutaka;Yabushita, Akihiro;Shimizu, Atsushi;Matsui, Ichiro;Sugimoto, Nobuo
    • Asian Journal of Atmospheric Environment
    • /
    • v.3 no.1
    • /
    • pp.27-41
    • /
    • 2009
  • Internally mixed states of submicron particles during transport from the Asian continent to the Pacific Ocean were analyzed using a single-particle time-offlight mass spectrometer. The observation was conducted at Tsukuba in Japan in the spring of 2005 in order to investigate springtime transport of particles from the continent. The sum of ion intensities of sulfate (${HSO_4}^-$) detected in particles originating from the continental air masses counted for 75% of that in all particles during the observation. By analyzing correlations among compounds, origins and internally mixed states of compounds were estimated. It was found that nitrate was mixed with sulfate-rich particles as the air mass approached Japan. It was confirmed that Asian mineral dust particles played significant roles for transport of continental sulfate to Japan. As a result of analysis on internal mixing of chlorine and nitrate, it was implied that the chlorine loss in fine sea salt particles had already proceeded at Tsukuba. It was characteristic that fluoride ions were significantly detected, coal combustion in the Asian Continent can be an important source of fluorides detected in Japan through the westward transportation of fine particles including fluorides.

Multi-sensor Single Maneuvering Target Tracking in Clutter using AMMPF (클러터를 고려한 다중 센서 환경에서의 AMMPF를 이용한 기동 표적 추적 알고리즘 연구)

  • Kim Da-Sol;Song Taek-Lyul;Oh Won-Chun
    • Proceedings of the Acoustical Society of Korea Conference
    • /
    • /
    • pp.479-482
    • /
    • 2004
  • In this article we consider a single maneuvering target Tracking algorithm in the presence of missing measurements and high clutter environments for multi-sensor target tracking problem. The tracking algorithm is based on the Particle filtering method to predict and update target states. Proposed is the AMM-PF(Auxiliary Multiple Model Particle Filter)[2] method for maneuvering target tracking to improve performance in track estimate and maintenance with a high level of uncertainty. The algorithm we propose is compared to the Extended Kalman Filter(EKF). A simulation study is included.

  • PDF

Quantum-behaved Electromagnetism-like Mechanism Algorithm for Economic Load Dispatch of Power System

  • Zhisheng, Zhang;Wenjie, Gong;Xiaoyan, Duan
    • Journal of Electrical Engineering and Technology
    • /
    • v.10 no.4
    • /
    • pp.1415-1421
    • /
    • 2015
  • This paper presents a new algorithm called Quantum-behaved Electromagnetism-like Mechanism Algorithm which is used to solve economic load dispatch of power system. Electromagnetism-like mechanism algorithm simulates attraction and repulsion mechanism for particles in the electromagnetic field. Every solution is a charged particle, and it move to optimum solution according to certain criteria. Quantum-behaved electromagnetism-like mechanism algorithm merges quantum computing theory with electromagnetism-like mechanism algorithm. Superposition characteristic of quantum methodology can make a single particle present several states, and the characteristic potentially increases population diversity. Probability representation of quantum methodology is to make particle state be presented according to a certain probability. And the quantum rotation gates are used to realize update operation of particles. The algorithm is tested for 13-generator system and 40-generator system, which validates it can effectively solve economic load dispatch problem. Through performance comparison, it is obvious the solution is superior to other optimization algorithm.

Eulerian Two-Phase Flow Analysis for Solid-Liquid Mixing in a Industrial Mixer (산업용 교반기의 고체-액체 혼합에 대한 Eulerian Two-Phase 유동해석)

  • Song, Ae-Kyung;Hur, Nahm-Keon;Won, Chan-Shik;Ahn, Ick-Jin
    • 유체기계공업학회:학술대회논문집
    • /
    • /
    • pp.471-474
    • /
    • 2006
  • The Mixer is apparatus that help precipitation or an inhomogeneous distribution of various phases to be mixed and that user makes necessary material mixing one or the other. Mainly the mixer which is used from chemical and food industry is very important system in engineering that mixes the material. The inside flow of the mixer under the actual states which put a basis in flow of the fluid is formed rotation of the impeller. The inside flow of impeller will be caused by various reasons change with shape of impeller, number of rotation, mixing material and flow pattern of free surface etc. Also mixer study depended in single-phase flow and experimental research. So the numerical analysis of flow mixing solid-fluid particle is simulated. It is become known, that the case where agitator inside working fluid includes the solid particle the sinkage reverse which the solid particle has decreases an agitation efficiency. From the research which it sees the hazard solid which examines the effect where the change of the sinkage territory which it follows agitation number of revolution and diameter of the particle goes mad to an agitator inside flow distribution - numerical analysis the inside flow distribution of liquid state with Eulerian Two-Phase Method.

  • PDF

Design and Implementation of Flexible Sensor to Measure Mechanical Stiffness of Soft Particles (Soft Particle의 강성 측정을 위한 단순한 구조의 유연 물질 센서의 개발)

  • Ihn, Yong Seok;Yang, Minho;Koo, Ja Choon
    • The Journal of Korea Robotics Society
    • /
    • v.11 no.3
    • /
    • pp.133-139
    • /
    • 2016
  • Increasing interest of human health, building bio-database (Bio DB) has been become a hot issue in life science. Consequently, Single Cell Analysis (SCA) which can explain biodiversity of lives has been a significant factor for building Bio DB. In numerous studies from these analyses, they have been showed that mechanical properties of cells can serve explanation of biological heterogeneity and criterion of disease states. Therefore, measuring mechanical properties of cells have great potential to be used in bio-medical applications. However, traditionally, many researchers have undergone difficult and time consuming work because handling small sized cells usually requires high-skilled technique. Thus, this paper shows robotized stiffness measurement technique using fixed ended beam sensor, precision motorized stage and substrate which have wall structure.

Influence of Dangling Bonds on Nanotribological Properties of Alpha-beam Irradiated Graphene

  • Hwang, Jinheui;Kim, Jong Hoon;Kwon, Sangku;Hwang, C.C.;Wu, Junqiao;Park, Jeong Young
    • Proceedings of the Korean Vacuum Society Conference
    • /
    • /
    • pp.265-265
    • /
    • 2013
  • We have investigated the influences of dangling bonds generated by alpha particle irradiation on friction and adhesion properties of graphene. Single layer of graphene grown with chemical vapor deposition on copper foil was irradiated by the alpha beam with the average energy of 3.04 MeV and the irradiation dosing between $1{\times}10^{14}$ and $1{\times}10^{15}$/$cm^3$. Raman spectroscopic showed that the ${\pi}$ electron states below Fermi level arises and the $I_D$/$I_G$ increases as increasing the dosing of alpha particle irradiation. The core level X-ray photoelectron (XPS) revealed that these defects represent the creation of various carbon-related defects and dangling bond. The nanoscale tribological properties were investigated with atomic force microscopy in ultrahigh vacuum. The friction appeared to increase remarkably as increasing the amount of dosing, indicating that the dangling bonds on graphene layers enhances the energy dissipations in friction. This trend can be explained by the additional channel of energy dissipation by dangling bond or O- and H- terminated clusters created by alpha particle irradiation.

  • PDF

PIV Measurements of the Flow characteristics around a single rudder in a backward state (역추진시 단동타 주위 유동특성에 대한 PIV계측)

  • Shon, Chang-Bae;Gim, Ok-Sok;Oh, Woo-Jun;Lee, Chang-Woo;Lee, Gyoung-Woo
    • Proceedings of the Korean Institute of Navigation and Port Research Conference
    • /
    • /
    • pp.383-384
    • /
    • 2010
  • The control surface on a ship is to control the motion of it in forward and backward states. In this paper, the measured results has been compared with each other to predict the backward flow characteristics of the single rudder's 2-dimensional section at $Re=2.0\times10^4$ using 2-frame grey level cross correlation PIV method especially, The separation region appears at 10 to 20 degrees angle of attack in a forward state. The separation point and boundary layer demonstrate in the same angle of attack compared it with the forward states.

  • PDF

Atomistic simulation of surface passivated wurtzite nanowires: electronic bandstructure and optical emission

  • Chimalgi, Vinay U.;Nishat, Md Rezaul Karim;Yalavarthi, Krishna K.;Ahmed, Shaikh S.
    • Advances in nano research
    • /
    • v.2 no.3
    • /
    • pp.157-172
    • /
    • 2014
  • The three-dimensional Nano-Electronic Modeling toolkit (NEMO 3-D) is an open source software package that allows the atomistic calculation of single-particle electronic states and optical response of various semiconductor structures including bulk materials, quantum dots, impurities, quantum wires, quantum wells and nanocrystals containing millions of atoms. This paper, first, describes a software module introduced in the NEMO 3-D toolkit for the calculation of electronic bandstructure and interband optical transitions in nanowires having wurtzite crystal symmetry. The energetics (Hamiltonian) of the quantum system under study is described via the tight-binding (TB) formalism (including $sp^3$, $sp^3s^*$ and $sp^3d^5s^*$ models as appropriate). Emphasis has been given in the treatment of surface atoms that, if left unpassivated, can lead to the creation of energy states within the bandgap of the sample. Furthermore, the developed software has been validated via the calculation of: a) modulation of the energy bandgap and the effective masses in [0001] oriented wurtzite nanowires as compared to the experimentally reported values in bulk structures, and b) the localization of wavefunctions and the optical anisotropy in GaN/AlN disk-in-wire nanowires.