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91.
92.
Emanuel Gull Philipp Werner Sebastian Fuchs Brigitte Surer Thomas Pruschke Matthias Troyer 《Computer Physics Communications》2011,182(4):1078-1082
Continuous-time quantum Monte Carlo impurity solvers are algorithms that sample the partition function of an impurity model using diagrammatic Monte Carlo techniques. The present paper describes codes that implement the interaction expansion algorithm originally developed by Rubtsov, Savkin, and Lichtenstein, as well as the hybridization expansion method developed by Werner, Millis, Troyer, et al. These impurity solvers are part of the ALPS-DMFT application package and are accompanied by an implementation of dynamical mean-field self-consistency equations for (single orbital single site) dynamical mean-field problems with arbitrary densities of states.
Program summary
Program title: dmftCatalogue identifier: AEIL_v1_0Program summary URL:http://cpc.cs.qub.ac.uk/summaries/AEIL_v1_0.htmlProgram obtainable from: CPC Program Library, Queen's University, Belfast, N. IrelandLicensing provisions: ALPS LIBRARY LICENSE version 1.1No. of lines in distributed program, including test data, etc.: 899 806No. of bytes in distributed program, including test data, etc.: 32 153 916Distribution format: tar.gzProgramming language: C++Operating system: The ALPS libraries have been tested on the following platforms and compilers:•
Linux with GNU Compiler Collection (g++ version 3.1 and higher), and Intel C++ Compiler (icc version 7.0 and higher) •
MacOS X with GNU Compiler (g++ Apple-version 3.1, 3.3 and 4.0) •
IBM AIX with Visual Age C++ (xlC version 6.0) and GNU (g++ version 3.1 and higher) compilers •
Compaq Tru64 UNIX with Compq C++ Compiler (cxx) •
SGI IRIX with MIPSpro C++ Compiler (CC) •
HP-UX with HP C++ Compiler (aCC) •
Windows with Cygwin or coLinux platforms and GNU Compiler Collection (g++ version 3.1 and higher)
[1]
A. Albuquerque, F. Alet, P. Corboz, et al., J. Magn. Magn. Mater. 310 (2007) 1187. [2]
http://arxiv.org/abs/1012.4474, Rev. Mod. Phys., in press.
93.
During summer and autumn 2007, a 11 GHz microwave radiometer was deployed in an experimental tree plantation in Sardinilla, Panama. The opacity of the tree canopy was derived from incoming brightness temperatures received on the ground. A collocated eddy-covariance flux tower measured water vapor fluxes and meteorological variables above the canopy. In addition, xylem sapflow of trees was measured within the flux tower footprint. We observed considerable diurnal differences between measured canopy opacities and modeled theoretical opacities that were closely linked to xylem sapflow. It is speculated that dielectric changes in the leaves induced by the sapflow are causing the observed diurnal changes. In addition, canopy intercepted rain and dew formation also modulated the diurnal opacity cycle. With an enhanced canopy opacity model accounting for water deposited on the leaves, we quantified the influence of canopy stored water (i.e. intercepted water and dew) on the opacity. A time series of dew formation and rain interception was directly monitored during a period of two weeks. We found that during light rainfall up to 60% of the rain amount is intercepted by the canopy whereas during periods of intense rainfall only 4% were intercepted. On average, 0.17 mm of dew was formed during the night. Dew evaporation contributed 5% to the total water vapor flux measured above the canopy. 相似文献
94.
Sebastian GunrebenAuthor Vitae 《Performance Evaluation》2011,68(3):237-255
Contention resolution schemes in optical burst switched networks (OBS) as well as contention avoidance schemes delay burst delivery and change the burst arrival sequence. The burst arrival sequence usually changes the packet arrival sequence and degrades the upper layer protocols performance, e.g., the throughput of the transmission control protocol (TCP).In this paper, we present and analyze a detailed burst reordering model for two widely applied burst assembly strategies: time-based and random selection. We apply the IETF reordering metrics and calculate explicitly three reordering metrics: the reordering ratio, the reordering extent metric and the TCP relevant metric. These metrics allow estimating the degree of reordering in a certain network scenario. They estimate the buffer space at the destination to resolve reordering and quantify the number of duplicate acknowledgements relevant for investigations on the transmission control protocol.We show that our model reflects the burst/packet reordering pattern of simulated OBS networks very well. Applying our model in a network emulation scenario, enables investigations on real protocol implementations in network emulation environments. It therefore serves as a substitute for extensive TCP over OBS network simulations with a focus on burst reordering. 相似文献
95.
For a word equation E of length n in one variable x occurring #
x
times in E a resolution algorithm of O(n+#
x
log n) time complexity is presented here. This is the best result known and for the equations that feature
#x < \fracnlogn\#_{x}<\frac{n}{\log n}
it yields time complexity of O(n) which is optimal. Additionally it is proven here that the set of solutions of any one-variable word equation is either of
the form F or of the form F∪(uv)+
u where F is a set of O(log n) words and u, v are some words such that uv is a primitive word. 相似文献
96.
Aligning DNA and protein sequences is a core technique in molecular biology. Often, it is desirable to include partial prior
knowledge and conditions in an alignment. Going beyond prior work, we aim at the integration of such side constraints in free
combination into alignment algorithms. The most common and successful technique for efficient alignment algorithms is dynamic
programming (DP). However, a weakness of DP is that one cannot include additional constraints without specifically tailoring
a new DP algorithm. Here, we discuss a declarative approach that is based on constraint techniques and show how it can be
extended by formulating additional knowledge as constraints. We take special care to obtain the efficiency of DP for sequence
alignment. This is achieved by careful modeling and applying proper solving strategies. Finally, we apply our method to the
scanning for RNA motifs in large sequences. This case study demonstrates how the new approach can be used in real biological
problems. A prototypic implementation of the method is available at . 相似文献
97.
Alternating-time temporal logic (atl) is a logic for reasoning about open computational systems and multi-agent systems. It is well known that atl model checking is linear in the size of the model. We point out, however, that the size of an atl model is usually exponential in the number of agents. When the size of models is defined in terms of states and agents rather than transitions, it turns out that the problem is (1) Δ
3
P
-complete for concurrent game structures, and (2) Δ
2
P
-complete for alternating transition systems. Moreover, for “Positive atl” that allows for negation only on the level of propositions, model checking is (1) Σ
2
P
-complete for concurrent game structures, and (2) NP-complete for alternating transition systems. We show a nondeterministic polynomial reduction from checking arbitrary alternating
transition systems to checking turn-based transition systems, We also discuss the determinism assumption in alternating transition
systems, and show that it can be easily removed.
In the second part of the paper, we study the model checking complexity for formulae of atl
with imperfect information (atl
ir
). We show that the problem is Δ
2
P
-complete in the number of transitions and the length of the formula (thereby closing a gap in previous work of Schobbens
in Electron. Notes Theor. Comput. Sci. 85(2), 2004). Then, we take a closer look and use the same fine structure complexity measure as we did for atl with perfect information. We get the surprising result that checking formulae of atl
ir
is also Δ
3
P
-complete in the general case, and Σ
2
P
-complete for “Positive atl
ir
”. Thus, model checking agents’ abilities for both perfect and imperfect information systems belongs to the same complexity
class when a finer-grained analysis is used. 相似文献
98.
The article concludes a series of results on cut-rule axiomatizabilityof the Lambek calculus. It is proved that the non-associativeproduct-free Lambek calculus with the empty string (NL0) isnot finitely axiomatizable if the only rule of inference admittedis Lambek's cut rule. The proof makes use of the (infinitely)cut-rule axiomatized calculus NC designed by the author exactlyfor that purpose. 相似文献
99.
As we can show that the two-variable monadic fragment of thefull first-order extension of the propositional branching time logic is not recursively enumerable, we show in thisarticle that the monodic fragment of can be axiomatized. 相似文献
100.
Anna Korzynska Wojciech Strojny Andreas Hoppe David Wertheim Pawel Hoser 《Pattern Analysis & Applications》2007,10(4):301-319
This paper describes a segmentation method combining a texture based technique with a contour based method. The technique
is designed to enable the study of cell behaviour over time by segmenting brightfield microscope image sequences. The technique
was tested on artificial images, based on images of living cells and on real sequences acquired from microscope observations
of neutrophils and lymphocytes as well as on a sequence of MRI images. The results of the segmentation are compared with the
results of the watershed and snake segmentation methods. The results show that the method is both effective and practical.
相似文献
Anna KorzynskaEmail: |