• Title/Summary/Keyword: Critical points

Search Result 860, Processing Time 0.026 seconds

The clustering of critical points in the evolving cosmic web

  • Shim, Junsup;Codis, Sandrine;Pichon, Christophe;Pogosyan, Dmitri;Cadiou, Corentin
    • The Bulletin of The Korean Astronomical Society
    • /
    • v.46 no.1
    • /
    • pp.47.2-47.2
    • /
    • 2021
  • Focusing on both small separations and baryonic acoustic oscillation scales, the cosmic evolution of the clustering properties of peak, void, wall, and filament-type critical points is measured using two-point correlation functions in ΛCDM dark matter simulations as a function of their relative rarity. A qualitative comparison to the corresponding theory for Gaussian random fields allows us to understand the following observed features: (i) the appearance of an exclusion zone at small separation, whose size depends both on rarity and signature (i.e. the number of negative eigenvalues) of the critical points involved; (ii) the amplification of the baryonic acoustic oscillation bump with rarity and its reversal for cross-correlations involving negatively biased critical points; (iii) the orientation-dependent small-separation divergence of the cross-correlations of peaks and filaments (respectively voids and walls) that reflects the relative loci of such points in the filament's (respectively wall's) eigenframe. The (cross-) correlations involving the most non-linear critical points (peaks, voids) display significant variation with redshift, while those involving less non-linear critical points seem mostly insensitive to redshift evolution, which should prove advantageous to model. The ratios of distances to the maxima of the peak-to-wall and peak-to-void over that of the peak-to-filament cross-correlation are ~2-√~2 and ~3-√~3WJ, respectively, which could be interpreted as the cosmic crystal being on average close to a cubic lattice. The insensitivity to redshift evolution suggests that the absolute and relative clustering of critical points could become a topologically robust alternative to standard clustering techniques when analysing upcoming surveys such as Euclid or Large Synoptic Survey Telescope (LSST).

  • PDF

Studies on the HACCP Model of Steak-Set Menu in Hotel (HACCP 모델 적용시 호텔 .레스토랑의 세트 메뉴 중 스테이크에 관한 연구)

  • 양신철
    • Journal of Applied Tourism Food and Beverage Management and Research
    • /
    • v.12 no.1
    • /
    • pp.5-24
    • /
    • 2001
  • This study was focused on the sanitary analysis of hazard factors and the establishment of critical control points on steak-set menu In hotel by the documents and microbiological investigation. The hazard factors of shrimp cocktail were microbial contamination, residual pesticides, unsuitable healing and cross contamination. The hazard factors of potato soap were residual pesticides, microorganisms contamination, unsuitable heating and solanine in potato. The hazard factors of simple salad were microorganisms contamination, unsuitable heating and cross contamination by inappropriate package. The hazard factors of steal were residual antimicrobial drugs, microorganisms contamination, unsuitable heating and cross contamination. The critical control points of shrimp cocktail were temperature control , number of washing and center temperature control of heating step. The critical control points of potato soup were stock temperature control , number of washing and center temperature control of Heating step. The critical control points of simple salad were number of washing and dryness of utensil. The critical control points of steak were stock temperature control , number of washing, center temperature and time control of heating step.

  • PDF

Localized Algorithm to Improve Connectivity and Topological Resilience of Multi-hop Wireless Networks

  • Kim, Tae-Hoon;Tipper, David;Krishnamurthy, Prashant
    • Journal of information and communication convergence engineering
    • /
    • v.11 no.2
    • /
    • pp.69-81
    • /
    • 2013
  • Maintaining connectivity is essential in multi-hop wireless networks since the network topology cannot be pre-determined due to mobility and environmental effects. To maintain the connectivity, a critical point in the network topology should be identified where the critical point is the link or node that partitions the network when it fails. In this paper, we propose a new critical point identification algorithm and also present numerical results that compare the critical points of the network and H-hop sub-network illustrating how effectively sub-network information can detect the network-wide critical points. Then, we propose two localized topological control resilient schemes that can be applied to both global and local H-hop sub-network critical points to improve the network connectivity and the network resilience. Numerical studies to evaluate the proposed schemes under node and link failure network conditions show that our proposed resilient schemes increase the probability of the network being connected in variety of link and node failure conditions.

EXISTENCE OF THREE SOLUTIONS FOR A CLASS OF NAVIER QUASILINEAR ELLIPTIC SYSTEMS INVOLVING THE (p1, …, pn)-BIHARMONIC

  • Li, Lin
    • Bulletin of the Korean Mathematical Society
    • /
    • v.50 no.1
    • /
    • pp.57-71
    • /
    • 2013
  • In this paper, we establish the existence of at least three solutions to a Navier boundary problem involving the ($p_1$, ${\cdots}$, $p_n$)-biharmonic systems. We use a variational approach based on a three critical points theorem due to Ricceri [B. Ricceri, A three critical points theorem revisited, Nonlinear Anal. 70 (2009), 3084-3089].

4-DIMENSIONAL CRITICAL WEYL STRUCTURES

  • Kim, Jong-Su
    • Bulletin of the Korean Mathematical Society
    • /
    • v.38 no.3
    • /
    • pp.551-564
    • /
    • 2001
  • We view Weyl structures as generalizations of Riemannian metrics and study the critical points of geometric functional which involve scalar curvature, defined on the space of Weyl structures on a closed 4-manifold. The main goal here is to provide a framework to analyze critical Weyl structures by defining functionals, discussing function spaces and writing down basic formulas for the equations of critical points.

  • PDF

Concurrent Modeling of Magnetic Field Parameters, Crystalline Structures, and Ferromagnetic Dynamic Critical Behavior Relationships: Mean-Field and Artificial Neural Network Projections

  • Laosiritaworn, Yongyut;Laosiritaworn, Wimalin
    • Journal of Magnetics
    • /
    • v.19 no.4
    • /
    • pp.315-322
    • /
    • 2014
  • In this work, Artificial Neural Network (ANN) was used to model the dynamic behavior of ferromagnetic hysteresis derived from performing the mean-field analysis on the Ising model. The effect of field parameters and system structure (via coordination number) on dynamic critical points was elucidated. The Ising magnetization equation was drawn from mean-field picture where the steady hysteresis loops were extracted, and series of the dynamic critical points for constructing dynamic phase-diagram were depicted. From the dynamic critical points, the field parameters and the coordination number were treated as inputs whereas the dynamic critical temperature was considered as the output of the ANN. The input-output datasets were divided into training, validating and testing datasets. The number of neurons in hidden layer was varied in structuring ANN network with highest accuracy. The network was then used to predict dynamic critical points of the untrained input. The predicted and the targeted outputs were found to match well over an extensive range even for systems with different structures and field parameters. This therefore confirms the ANN capabilities and indicates the ANN ability in modeling the ferromagnetic dynamic hysteresis behavior for establishing the dynamic-phase-diagram.

MULTIPLICITY RESULTS AND THE M-PAIRS OF TORUS-SPHERE VARIATIONAL LINKS OF THE STRONGLY INDEFINITE FUNCTIONAL

  • Jung, Tack-Sun;Choi, Q-Heung
    • Journal of the Korean Society for Industrial and Applied Mathematics
    • /
    • v.12 no.4
    • /
    • pp.239-247
    • /
    • 2008
  • Let $I{\in}C^{1,1}$ be a strongly indefinite functional defined on a Hilbert space H. We investigate the number of the critical points of I when I satisfies two pairs of Torus-Sphere variational linking inequalities and when I satisfies m ($m{\geq}2$) pairs of Torus-Sphere variational linking inequalities. We show that I has at least four critical points when I satisfies two pairs of Torus-Sphere variational linking inequality with $(P.S.)^*_c$ condition. Moreover we show that I has at least 2m critical points when I satisfies m ($m{\geq}2$) pairs of Torus-Sphere variational linking inequalities with $(P.S.)^*_c$ condition. We prove these results by Theorem 2.2 (Theorem 1.1 in [1]) and the critical point theory on the manifold with boundary.

  • PDF

THE NUMBER OF THE CRITICAL POINTS OF THE STRONGLY INDEFINITE FUNCTIONAL WITH ONE PAIR OF THE TORUS-SPHERE VARIATIONAL LINKING SUBLEVELS

  • Jung, Tacksun;Choi, Q-Heung
    • Korean Journal of Mathematics
    • /
    • v.16 no.4
    • /
    • pp.527-535
    • /
    • 2008
  • Let $I{\in}C^{1,1}$ be a strongly indefinite functional defined on a Hilbert space H. We investigate the number of the critical points of I when I satisfies one pair of Torus-Sphere variational linking inequality. We show that I has at least two critical points when I satisfies one pair of Torus-Sphere variational linking inequality with $(P.S.)^*_c$ condition. We prove this result by use of the limit relative category and critical point theory on the manifold with boundary.

  • PDF

Microbial Modeling in Quantitative Risk Assessment for the Hazard Analysis and Critical Control Point (HACCP) System: A Review

  • Min, Sea-Cheol;Choi, Young-Jin
    • Food Science and Biotechnology
    • /
    • v.18 no.2
    • /
    • pp.279-293
    • /
    • 2009
  • Quantitative risk assessments are related to implementing hazard analysis and critical control points (HACCP) by its potential involvement in identifying critical control points (CCPs), validating critical limits at a CCP, enabling rational designs of new processes, and products to meet required level of safety, and evaluating processing operations for verification procedures. The quantitative risk assessment is becoming a standard research tool which provides useful predictions and analyses on microbial risks and, thus, a valuable aid in implementing a HACCP system. This paper provides a review of microbial modeling in quantitative risk assessments, which can be applied to HACCP systems.

SOME RIGIDITY CHARACTERIZATIONS OF EINSTEIN METRICS AS CRITICAL POINTS FOR QUADRATIC CURVATURE FUNCTIONALS

  • Huang, Guangyue;Ma, Bingqing;Yang, Jie
    • Bulletin of the Korean Mathematical Society
    • /
    • v.57 no.6
    • /
    • pp.1367-1382
    • /
    • 2020
  • We study rigidity results for the Einstein metrics as the critical points of a family of known quadratic curvature functionals involving the scalar curvature, the Ricci curvature and the Riemannian curvature tensor, characterized by some pointwise inequalities involving the Weyl curvature and the traceless Ricci curvature. Moreover, we also provide a few rigidity results for locally conformally flat critical metrics.