Search results for "Diagram"
showing 10 items of 795 documents
Freshening of the Alaska Coastal Current recorded by coralline algal Ba/Ca ratios
2011
Arctic Ocean freshening can exert a controlling influence on global climate, triggering strong feedbacks on ocean‐atmospheric processes and affecting the global cycling of the world’s oceans. Glacier‐fed ocean currents such as the Alaska Coastal Current are important sources of freshwater for the Bering Sea shelf, and may also influence the Arctic Ocean freshwater budget. Instrumental data indicate a multiyear freshening episode of the Alaska Coastal Current in the early 21st century. It is uncertain whether this freshening is part of natural multidecadal climate variability or a unique feature of anthropogenically induced warming. In order to answer this, a better understanding of past var…
SAL—A Novel Quality Measure for the Verification of Quantitative Precipitation Forecasts
2008
Abstract A novel object-based quality measure, which contains three distinct components that consider aspects of the structure (S), amplitude (A), and location (L) of the precipitation field in a prespecified domain (e.g., a river catchment) is introduced for the verification of quantitative precipitation forecasts (QPF). This quality measure is referred to as SAL. The amplitude component A measures the relative deviation of the domain-averaged QPF from observations. Positive values of A indicate an overestimation of total precipitation; negative values indicate an underestimation. For the components S and L, coherent precipitation objects are separately identified in the forecast and obser…
A laboratory study on the uptake of HCl, HNO3, and SO2 gas by ice crystals and the effect of these gases on the evaporation rate of the crystals
1998
The results of our new and earlier laboratory studies on the uptake of gases by ice crystals are summarized in terms of (1) the equilibrium phase diagram for a system gas/H2O, (2) the effect of these gases on the evaporation rate of ice crystals, and (3) in terms of the uptake of the gases by water drops. It is shown that the intrinsic quasi-liquid layer significantly affects the uptake of a gas by an ice surface in that, depending on the gas phase concentration, the layer thickness may be considerably increased by depressing the equilibrium freezing point causing additional surface melting. It is further shown that the evaporation rate of ice particles previously exposed to a gas may becom…
Data flow of spectral UV measurements at Sodankylä and Jokioinen
2016
Abstract. The data flow involved in a long-term continuous solar spectral UV irradiance monitoring program is investigated and structured to provide an overall view on the multiphase process from data acquisition to the final products. The program employing Brewer spectrophotometers as measuring instruments is maintained by the Finnish Meteorological Institute (FMI) ever since the 1990s at two sites in Finland: Sodankylä (67° N) and Jokioinen (61° N). It is built upon rigorous operation routines, processing procedures, and tools for quality control (QC) and quality analysis (QA) under continuous development and evaluation. Three distinct levels of data emerge, each after certain phase in th…
Unconventional phases of attractive Fermi gases in synthetic Hall ribbons
2017
An innovative way to produce quantum Hall ribbons in a cold atomic system is to use M hyperfine states of atoms in a one-dimensional optical lattice to mimic an additional "synthetic dimension." A notable aspect here is that the SU(M) symmetric interaction between atoms manifests as "infinite ranged" along the synthetic dimension. We study the many-body physics of fermions with SU(M) symmetric attractive interactions in this system using a combination of analytical field theoretic and numerical density-matrix renormalization-group methods. We uncover the rich ground-state phase diagram of the system, including unconventional phases such as squished baryon fluids, shedding light on many-body…
Zvaigžņotā Debess: 2010/11, Ziema (210)
2010
Contents: “ZVAIGŅOTĀ DEBESS” FORTY YEARS AGO: Bursting Stars. J. Francman (abridged). Geodesists Help Renew the Spire of St. Peter’s Church. J. Klētnieks (abridged). DEVELOPMENTS in SCIENCE: The Solar Neutrino Problem. O. Smirnova. NEWS: At Last the Planet at the Star β Pictoris Is Imaged. A. Alksnis, Z. Alksne. SPACE RESEARCH and EXPLORATION: The Trail of an Asteroid Reveals a Recent Collision. A. Alksnis. INTERNATIONAL YEAR of ASTRONOMY 2009: International Year of Astronomy 2009 in Philately. The Rest of the World except Series EUROPA (concluded). J. Limansky. ACADEMIC STAFF of the UNIVERSITY of LATVIA: Assistant Professor in Physics Ojārs Šmits (24.04.1930.-14.03.1993.) of the Latvian Un…
A model for the γN → ππN reaction
1995
We have studied the γN→ππN reaction using a model which includes N, Δ(1232), N*(1440) and N*(1520) intermediate baryonic states and the ρ-meson as intermediate ππ resonance. The model reproduces fairly well experimental cross sections below E γ = 800 MeV and invariant-mass distributions even at higher energies. One of the interesting findings of the study is that the γ N →N*(1520) → Δπ process is very important and interferes strongly with the dominant Δ-Kroll-Ruderman term to produce the experimental peak of the cross section.
A comparison of deontic matrices, maps and activity diagrams for the construction of situational methods
2007
Several approaches have been proposed to support situational method engineering (SME), each of them providing different techniques and using different basic concepts. In this work, we propose a framework for comparing SME approaches based on a generic SME process model. Three approaches are presented and compared by using this framework.
Ab Initio Study of BiFeO3: Thermodynamic Stability Conditions
2015
BiFeO3 is investigated intensively, mainly as a multiferroic material. In this paper, the state-of-the-art ab initio hybrid functional approach with atomic basis sets was employed for a study of the stability range of BiFeO3 with respect to its decomposition into binary oxides and elementary metals, as a function of temperature and oxygen partial pressure. The calculated atomic and electronic structure of BiFeO3 was compared with previous LDA+U calculations using plane-wave basis sets. Based on performed calculations, the phase diagram was constructed, which allows us to predict the stability region of stoichiometric BiFeO3.
Double precision errors in the logistic map: statistical study and dynamical interpretation.
2007
The nature of the round-off errors that occur in the usual double precision computation of the logistic map is studied in detail. Different iterative regimes from the whole panoply of behaviors exhibited in the bifurcation diagram are examined, histograms of errors in trajectories given, and for the case of fully developed chaos an explicit formula is found. It is shown that the statistics of the largest double precision error as a function of the map parameter is characterized by jumps whose location is determined by certain boundary crossings in the bifurcation diagram. Both jumps and locations seem to present geometric convergence characterized by the two first Feigenbaum constants. Even…