ALBERT

All Library Books, journals and Electronic Records Telegrafenberg

X
feed icon rss

Your email was sent successfully. Check your inbox.

An error occurred while sending the email. Please try again.

Proceed reservation?

Export
Filter
  • Articles  (112)
  • Institute of Physics  (65)
  • Springer  (47)
  • Physics  (106)
  • Geosciences  (23)
  • Computer Science  (3)
  • Ethnic Sciences
Collection
  • Articles  (112)
Source
Keywords
Publisher
Years
Journal
Topic
  • 1
    Electronic Resource
    Electronic Resource
    Imaging the Gas Distribution and Kinematics in the Early Universe with ALMA (1999)
    Springer
    Astrophysics and space science 269-270 (1999), S. 533-540 
    Details
    ISSN: 1572-946X
    Source: Springer Online Journal Archives 1860-2000
    Topics: Physics
    Notes: Abstract A summary is presented of the status of the Atacama Large Millimeter Array (ALMA) project. The scientific goals for the project, in particular the goals for imaging gas in early galaxies, are used to illustrate the specific needs for the development of ALMA technology making it, uniquely, a complete imaging system. The plans to achieve this development by means of common international effort and under a common Memorandum of Understanding are noted. Finally, estimates are given of the construction timescale and the principle issues that remain to be settled are highlighted.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1023/A:1017083416083
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 2
    Electronic Resource
    Electronic Resource
    Near resonant charge transfer processes at thermal energies (1972)
    Springer
    Astrophysics and space science 16 (1972), S. 274-283 
    Details
    ISSN: 1572-946X
    Source: Springer Online Journal Archives 1860-2000
    Topics: Physics
    Notes: Abstract A useful procedure is described for the evaluation of near resonant charge transfer cross-sections at thermal energies. The method is based on a generalization of a semi-classical approach introduced by Bates and Mapleton for the study of symmetric resonant charge transfer processes. The rate coefficient is calculated for the reaction O++H⇆H++O as a function of temperature between 10 and 104 K; the results are compared to those obtained using the ‘orbiting approximation’. A brief application of these rates to the interstellar medium is made where it is found that substantial differences emerge between cases where the gas is heated by cosmic rays or by X-Rays.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00642739
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 3
    Electronic Resource
    Electronic Resource
    Chemical composition of the interstellar gas: X-ray determinations (1972)
    Springer
    Astrophysics and space science 18 (1972), S. 329-333 
    Details
    ISSN: 1572-946X
    Source: Springer Online Journal Archives 1860-2000
    Topics: Physics
    Notes: Abstract Noting that observations of X-ray attenuation at theK-shell ionization edge for many elements provide, prospectively, the least ambiguous means for establishing the chemical composition of the interstellar gas, we have evaluated the expected spectral discontinuities for all atoms from carbon to sodium and have tabulated the results. It is shown that with X-ray detectors of reasonable energy resolution and sensitivity theK-shell edges of C, N, O, Ne, Si, S, A and Mg are potentially observable if the ‘cosmic’ abundances are representative of the general interstellar environment.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00645397
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 4
    Electronic Resource
    Electronic Resource
    Anomalous fluorescence properties of 4-N,N-dimethylaminobenzoic acid in polar solvents (1992)
    Springer
    Journal of fluorescence 2 (1992), S. 107-115 
    Details
    ISSN: 1573-4994
    Keywords: Fluorescence ; anomalous fluorescence ; 4-N,N-dimethylaminobenzoic acid ; dimerization
    Source: Springer Online Journal Archives 1860-2000
    Topics: Physics
    Notes: Abstract 4-N,N-Dimethylaminobenzoic acid exhibits anomalous fluorescence in polar and hydrogen-bonding solvents. The fluorescence spectra and kinetics suggest that this arises due to the formation of a ground-state dimer or higher polymer. Preliminary measurements in hexane containing small amounts of polar acetonitrile do not rule out the possibility of exciplex formation also occurring.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00867670
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 5
    Electronic Resource
    Electronic Resource
    Parallel implementation of finite-element/newton method for solution of steady-state and transient nonlinear partial differential equations (1995)
    Springer
    Journal of scientific computing 10 (1995), S. 93-137 
    Details
    ISSN: 1573-7691
    Keywords: Domain decomposition ; nested dissection ; LU-factorization ; time integration ; Newton's method ; spectral elements ; finite elements
    Source: Springer Online Journal Archives 1860-2000
    Topics: Computer Science
    Notes: Abstract Domain decomposition by nested dissection for concurrent factorization and storage (CFS) of asymmetric matrices is coupled with finite element and spectral element discretizations and with Newton's method to yield an algorithm for parallel solution of nonlinear initial-and boundary-value problem. The efficiency of the CFS algorithm implemented on a MIMD computer is demonstrated by analysis of the solution of the two-dimensional, Poisson equation discretized using both finite and spectral elements. Computation rates and speedups for the LU-decomposition algorithm, which is the most time consuming portion of the solution algorithm, scale with the number of processors. The spectral element discretization with high-order interpolating polynomials yields especially high speedups because the ratio of communication to computation is lower than for low-order finite element discretizations. The robustness of the parallel implementation of the finite-element/Newton algorithm is demonstrated by solution of steady and transient natural convection in a two-dimensional cavity, a standard test problem for low Prandtl number convection. Time integration is performed using a fully implicit algorithm with a modified Newton's method for solution of nonlinear equations at each time step. The efficiency of the CFS version of the finite-element/Newton algorithm compares well with a spectral element algorithm implemented on a MIMD computer using iterative matrix methods.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF02087962
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 6
    Electronic Resource
    Electronic Resource
    An incomplete nested dissection algorithm for parallel direct solution of finite element discretizations of partial differential equations (1993)
    Springer
    Journal of scientific computing 8 (1993), S. 373-387 
    Details
    ISSN: 1573-7691
    Keywords: Domain decomposition ; nested dissection ; LU-factorization ; parallel computers ; MIMD
    Source: Springer Online Journal Archives 1860-2000
    Topics: Computer Science
    Notes: Abstract A multilevel algorithm is presented for direct, parallel factorization of the large sparse matrices that arise from finite element and spectral element discretization of elliptic partial differential equations. Incomplete nested dissection and domain decomposition are used to distribute the domain among the processors and to organize the matrix into sections in which pivoting is applied to stabilize the factorization of indefinite equation sets. The algorithm is highly parallel and memory efficient; the efficient use of sparsity in the matrix allows the solution of larger problems as the number of processors is increased, and minimizes computations as well as the number and volume of communications among the processors. The number of messages and the total volume of messages passed during factorization, which are used as measures of algorithm efficiency, are reduced significantly compared to other algorithms. Factorization times are low and speedups high for implementation on an Intel iPSC/860 hypercube computer. Furthermore, the timings for forward and back substitutions are more than an order-of-magnitude smaller than the matrix decomposition times.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF01061145
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 7
    Electronic Resource
    Electronic Resource
    Observations of longitudinal roll vortices during arctic cold air outbreaks over open water (1988)
    Springer
    Boundary layer meteorology 45 (1988), S. 177-199 
    Details
    ISSN: 1573-1472
    Source: Springer Online Journal Archives 1860-2000
    Topics: Geosciences , Physics
    Notes: Abstract An evolving convective Arctic planetary boundary layer (PBL) containing longitudinal roll vortices (rolls) was observed with aircraft data during the 1983 Marginal Ice Zone Experiment and the 1984 Arctic Cyclone Experiment. The PBL is observed to grow rapidly as the very cold and dry air flows off the ice over the relatively warm water. There is very large sensible heat flux, a result of the large surface-air temperature differences. Coherent structures were identified in these PBL's by use of power, coherence squared and phase spectra of the data. A systematic method of separating the rolls from organized thermal plumes was devised, based on theoretical characteristics for roll circulations and the resulting modified mean wind profile. The rapid mixing by the rolls aids in the establishment of equilibrium and an observed adiabatic modified mean Ekman layer. Rolls that form in a thermally neutral atmosphere over ice have different characteristics than those that appear in the unstable stratification over water. The rolls become increasingly more convective in character with distance from the ice edge. They have aspect ratios (wavelength/PBL height) that decrease with distance from the ice edge in agreement with linear theory. This is in contrast to the cloud street wavelength to inversion height ratio which is observed to increase downwind from the ice edge.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00120822
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 8
    Electronic Resource
    Electronic Resource
    Evidence of Organized Large Eddies by Ground-Based Doppler Lidar, Sonic Anemometer and Sodar (1998)
    Springer
    Boundary layer meteorology 88 (1998), S. 343-361 
    Details
    ISSN: 1573-1472
    Keywords: Heterodyne Doppler lidar ; Organized large eddies ; Planetary boundary laye ; Turbulence
    Source: Springer Online Journal Archives 1860-2000
    Topics: Geosciences , Physics
    Notes: Abstract In an experiment investigating the planetary boundary layer (PBL) wind and temperature fields, and PBL inversion height recorded by various instruments, the results reveal the presence of organized large eddies (OLE) or rolls. The measurements by lidars, anemometers, soundings and sodar gave an overview of the characteristics of the rolls and sources of energy production that maintain them. The experimental results obtained on two consecutive days are compared to model outputs. The agreement is excellent, showing that thermal stratification and wind shear are important factors in the structure and dynamics of OLE. A heterodyne Doppler lidar (HDL) is shown to be a useful tool in the study of OLE.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1023/A:1001167212584
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 9
    Electronic Resource
    Electronic Resource
    Climate Change Impacts on the Potential Productivity of Corn and Winter Wheat in Their Primary United States Growing Regions (1999)
    Springer
    Climatic change 41 (1999), S. 73-107 
    Details
    ISSN: 1573-1480
    Source: Springer Online Journal Archives 1860-2000
    Topics: Geosciences , Physics
    Notes: Abstract We calculate the impacts of climate effects inferred from three atmospheric general circulation models (GCMs) at three levels of climate change severity associated with change in global mean temperature (GMT) of 1.0, 2.5 and 5.0 °C and three levels of atmospheric CO2 concentration ([CO2]) – 365 (no CO2 fertilization effect), 560 and 750 ppm – on the potential production of dryland winter wheat (Triticum aestivum L.) and corn (Zea mays L.) for the primary (current) U.S. growing regions of each crop. This analysis is a subset of the Global Change Assessment Model (GCAM) which has the goal of integrating the linkages and feedbacks among human activities and resulting greenhouse gas emissions, changes in atmospheric composition and resulting climate change, and impacts on terrestrial systems. A set of representative farms was designed for each of the primary production regions studied and the Erosion Productivity Impact Calculator (EPIC) was used to simulate crop response to climate change. The GCMs applied were the Goddard Institute of Space Studies (GISS), the United Kingdom Meteorological Transient (UKTR) and the Australian Bureau of Meteorological Research Center (BMRC), each regionalized by means of a scenario generator (SCENGEN). The GISS scenarios have the least impact on corn and wheat production, reducing national potential production for corn by 6% and wheat by 7% at a GMT of 2.5 °C and no CO2 fertilization effect; the UKTR scenario had the most severe impact on wheat, reducing production by 18% under the same conditions; BMRC had the greatest negative impact on corn, reducing production by 20%. A GMT increase of 1.0°C marginally decreased corn and wheat production. Increasing GMT had a detrimental impact on both corn and wheat production, with wheat production suffering the greatest losses. Decreases for wheat production at GMT 5.0 and [CO2] = 365 ppm range from 36% for the GISS to 76% for the UKTR scenario. Increases in atmospheric [CO2] had a positive impact on both corn and wheat production. AT GMT 1.0, an increase in [CO2] to 560 ppm resulted in a net increase in corn and wheat production above baseline levels (from 18 to 29% for wheat and 2 to 5% for corn). Increases in [CO2] help to offset yield reductions at higher GMT levels; in most cases, however, these increases are not sufficient to return crop production to baseline levels.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1023/A:1005449132633
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 10
    Electronic Resource
    Electronic Resource
    Evidence of a Mixed-Layer Dynamics Contribution to the Entrainment Process (1999)
    Springer
    Boundary layer meteorology 93 (1999), S. 47-73 
    Details
    ISSN: 1573-1472
    Keywords: Boundary-layer model ; Mixed-layer dynamics ; Organized large eddies ; Ekman flow ; Cold-air outbreak
    Source: Springer Online Journal Archives 1860-2000
    Topics: Geosciences , Physics
    Notes: Abstract The internal thermal boundary layer developing over the Mediterranean during a cold-air outbreak associated with a Tramontane event has been studied by means of airborne lidar, in situ sensors, and a modelling approach that consisted of nesting the University of Washington (UW) planetary boundary-layer (PBL) model in an advective zero-order jump model. This approach bypasses some of the deficiencies associated with each model: the absence of the dynamics in the mixed layer for the zero-order jump model and the lack of an inversion at the PBL top for the UW PBL model. Particular attention is given to the parameterization of the entrainment flux at the PBL top. Values of the entrainment closure parameter derived with the model when matching PBL structure observations are much lower than those derived with standard zero-order jump models. They also are in good agreement with values measured in different meteorological situations by other studies. This improvement is a result of the introduction of turbulent kinetic energy production in the mixed layer.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1023/A:1002083425811
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...