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21.
Abhishek Arun Barry Haddow Philipp Koehn Adam Lopez Chris Dyer Phil Blunsom 《Machine Translation》2010,24(2):103-121
Recent advances in statistical machine translation have used approximate beam search for NP-complete inference within probabilistic
translation models. We present an alternative approach of sampling from the posterior distribution defined by a translation
model. We define a novel Gibbs sampler for sampling translations given a source sentence and show that it effectively explores
this posterior distribution. In doing so we overcome the limitations of heuristic beam search and obtain theoretically sound
solutions to inference problems such as finding the maximum probability translation and minimum risk training and decoding. 相似文献
22.
U. P. Hausmann Philipp Joerges J. Heinzl F. E. Talke 《Microsystem Technologies》2009,15(10-11):1747-1751
To increase the storage density of hard disk drives, the flying height of the slider needs to be reduced to <10 nm. This requires super-smooth surfaces of the disk and slider. As the roughness decreases, stiction and adhesion are found to increase substantially leading to failures of the head/disk interface. Texturing the slider surface is a well-known approach to this issue. In this study we investigated laser ablation as a potential process for texturing magnetic recording sliders. It was found that straight laser machining caused unwanted re-deposition of material. These deposits could be significantly reduced by using a chemical etching enhanced laser process. 相似文献
23.
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.
24.
We investigate the use of two‐level nested grids as acceleration structure for ray tracing of dynamic scenes. We propose a massively parallel, sort‐based construction algorithm and show that the two‐level grid is one of the structures that is fastest to construct on modern graphics processors. The structure handles non‐uniform primitive distributions more robustly than the uniform grid and its traversal performance is comparable to those of other high quality acceleration structures used for dynamic scenes. We propose a cost model to determine the grid resolution and improve SIMD utilization during ray‐triangle intersection by employing a hybrid packetization strategy. The build times and ray traversal acceleration provide overall rendering performance superior to previous approaches for real time rendering of animated scenes on GPUs. 相似文献
25.
Long-lived renaming allows processes to repeatedly get distinct names from a small name space and release these names. This
paper presents two long-lived renaming algorithms in which the name a process gets is bounded above by the number of processes
currently occupying a name or performing one of these operations. The first algorithm is asynchronous, uses LL/SC objects, and has step complexity that is linear in the number of processes, c, currently getting or releasing a name. The second is synchronous, uses registers and counters, and has step complexity that
is polylogarithmic in c. Both tolerate any number of process crashes. 相似文献
26.
Martin Dietzfelbinger Jonathan E. Rowe Ingo Wegener Philipp Woelfel 《Algorithmica》2011,59(3):301-322
We investigate the effects of precision on the efficiency of various local search algorithms on 1-D unimodal functions. We
present a (1+1)-EA with adaptive step size which finds the optimum in O(log n) steps, where n is the number of points used. We then consider binary (base-2) and reflected Gray code representations with single bit mutations.
The standard binary method does not guarantee locating the optimum, whereas using the reflected Gray code does so in Θ((log n)2) steps. A(1+1)-EA with a fixed mutation probability distribution is then presented which also runs in O((log n)2). Moreover, a recent result shows that this is optimal (up to some constant scaling factor), in that there exist unimodal
functions for which a lower bound of Ω((log n)2) holds regardless of the choice of mutation distribution. For continuous multimodal functions, the algorithm also locates
the global optimum in O((log n)2). Finally, we show that it is not possible for a black box algorithm to efficiently optimise unimodal functions for two or
more dimensions (in terms of the precision used). 相似文献
27.
28.
Jan Birnstock Tobias Canzler Michael Hofmann Andrea Lux Sven Murano Philipp Wellmann Ansgar Werner 《Journal of the Society for Information Display》2008,16(2):221-229
Abstract— Currently, three issues are identified that decide upon the commercial success of organic light‐emitting diodes (OLEDs), both in display and lighting applications: power efficiency, lifetime, and price competitiveness. PIN OLEDs are widely seen as the preferred way to maximize power efficiency. Here, it is reported that this concept also delivers the world longest lifetimes. For a highly efficient deep‐red PIN OLED, a half‐lifetime of 25,000 hours for a starting brightness of 10,000 cd/m2 and a minimal voltage increase over lifetime is reported. This value corresponds to more than 1 × 106 hours at 1000 cd/m2 using an exponent of n = 1.7, which was measured by driving the OLEDs at different starting luminances. Because there is no initial luminance drop, these PIN OLEDs also exhibit a very high 80% lifetime (>300,000 hours at 1000 cd/m2). New record lifetime values for blue and green will be reported as well. Additionally, further topics that have impact on the production yield and cost such as the newly developed air‐stable organic n‐doping material NDN‐26 and top‐emitting structures will be discussed. 相似文献
29.
Analyzing the design of networks for visual information routing is an underconstrained problem due to insufficient anatomical and physiological data. We propose here optimality criteria for the design of routing networks. For a very general architecture, we derive the number of routing layers and the fanout that minimize the required neural circuitry. The optimal fanout l is independent of network size, while the number k of layers scales logarithmically (with a prefactor below 1), with the number n of visual resolution units to be routed independently. The results are found to agree with data of the primate visual system. 相似文献
30.
The dispersion of spray drops within a two-phase-flow is signified by an deformable phase interface where material properties suddenly change. The process of atomisation could previously only be modelled for standard applications simultaneously coupled with substantial simulations. In this case the process of atomisation is not coupled to the direct numerical simulation (DNS) of the interaction between two liquids. The approach of disintegration is modelled by statistics, describing the probability of generating liquid droplets. Therefore consideration of potential time and length for an intact liquid core are supposed from standard applications [1, 2]. Using this way of describing atomisation is utilised in a CFD-Code and then compared with PDA-measurements to control the process capability of this implementation.
Zusammenfassung Zweiphasenströmungen zeichnen sich durch eine bewegliche und deformierbare Phasengrenze aus. An dieser Phasengrenze ändern sich die Stoffeigenschaften sprunghaft. Die Erfassung und Beschreibung dieser Grenzflächeneigenschaften ist sehr aufwendig, so dass die numerische Modellierung von Zerstäubungsprozessen bisher nur für exemplarische Einzelfälle eingesetzt wird. Bei dieser Simulation von Zerstäubungsprozessen ist ein hoher Rechenaufwand gegeben. Der Vorgang des Strahlzerfalls lässt sich, wie im Folgenden dargestellt, mittels Zerfallswahrscheinlichkeiten abbilden. Aerodynamische Grenzflächenbetrachtungen fließen bei dieser Betrachtungsweise nicht in das Modell ein. Bei der Verwendung von Zerfallswahrscheinlichkeiten werden Annahmen zu Länge und Zeit der intakten Strahllänge der flüssigen Phase getroffen, die sich aus ähnlichen technischen Fragestellungen in direkten numerischen Simulationen (DNS) ableiten lassen [1,2]. Durch Anwendung von statistisch erzeugten Tropfenspektren in einem Strömungscode und durch Messung mittels Phasen-Doppler-Anemometrie erfolgt die Überprüfung der Aussagefähigkeit des statistischen Modells.相似文献