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71.
We define realizability semantics for Light Affine Logic (
LAL\mathsf{LAL}
) which has the property that denotations of functions are polynomial time computable by construction of the model. This gives
a new proof of polytime-soundness of
LAL\mathsf{LAL}
which is considerably simpler than the standard proof based on proof nets and is entirely semantical in nature. The model
construction uses a new instance of a resource monoid; a general method for interpreting systems based on Linear Logic introduced
earlier by the authors. 相似文献
72.
Lutz Hofmann Tobias Fischer Thomas Werner Franz Selbmann Michael Rennau Ramona Ecke Stefan E. Schulz Thomas Geßner 《Microsystem Technologies》2016,22(7):1665-1677
This paper discusses approaches for the isolation of deep high aspect ratio through silicon vias (TSV) with respect to a Via Last approach for micro-electro-mechanical systems (MEMS). Selected TSV samples have depths in the range of 170…270 µm and a diameter of 50 µm. The investigations comprise the deposition of different layer stacks by means of subatmospheric and plasma enhanced chemical vapour deposition (PECVD) of tetraethyl orthosilicate; Si(OC2H5)4 (TEOS). Moreover, an etch-back approach and the selective deposition on SiN were also included in the investigations. With respect to the Via Last approach, the contact opening at the TSV bottom by means of a specific spacer-etching method have been addressed within this paper. Step coverage values of up to 74 % were achieved for the best of those approaches. As an alternative to the SiO2-isolation liners a polymer coating based on the CVD of Parylene F was investigated, which yields even higher step coverage in the range of 80 % at the lower TSV sidewall for a surface film thickness of about 1000 nm. Leakage current measurements were performed and values below 0.1 nA/cm2 at 10 kV/cm were determined for the Parylene F films which represents a promising result for the aspired application to Via Last MEMS-TSV. 相似文献
73.
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.
74.
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
75.
The datasets used in statistical analyses are often small in the sense that the number of observations n is less than 5 times the number of parameters p to be estimated. In contrast, methods of robust regression are usually optimized in terms of asymptotics with an emphasis on efficiency and maximal bias of estimated coefficients. Inference, i.e., determination of confidence and prediction intervals, is proposed as complementary criteria. An analysis of MM-estimators leads to the development of a new scale estimate, the Design Adaptive Scale Estimate, and to an extension of the MM-estimate, the SMDM-estimate, as well as a suitable ψ-function. A simulation study shows and a real data example illustrates that the SMDM-estimate has better performance for small n/p and that the use the new scale estimate and of a slowly redescending ψ-function is crucial for adequate inference. 相似文献
76.
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
77.
Herbert Wieser Wolfgang Stempfl Werner Grosch und Hans-Dieter Belitz 《Zeitschrift für Lebensmitteluntersuchung und -Forschung A》1984,179(6):447-449
Zusammenfassung Achtzehn Fettsäuren, Fettsäuremethylester und Fettalkohole, emulgiert in Wasser mit Sucrosepalmitatstearat, wurden auf ihre Geschmacksqualität untersucht; bei bitterschmeckenden Verbindungen wurden die Schwellenwerte bestimmt. Die Intensität des Bittergeschmacks von Fettsäuren und Fettalkoholen hängt von der Länge des Alkylrestes sowie von der Anzahl, der Konfiguration und der Position der Doppelbindungen ab. Linol- und Linolensäuremethylester schmecken nicht bitter. -Linolenylalkohol und -Linolensäure haben die niedrigsten Schwellenwerte (0,2–0,5 bzw. 0,6–1,2 mmol/l) und liegen etwa im gleichen Bereich wie Coffein (0,8–1,2 mmol/l).
Studies of the bitter taste of fatty acid emulsions
Summary Eighteen fatty acids, methyl esters of fatty acids and fatty alcohols emulsified in water with sucrose palmitate stearate were tested for taste quality. In the case of bitter tasting compounds the taste thresholds were determined. The intensity of bitter taste of fatty acids and fatty alcohols is dependent on the length of the hydrocarbon chain and on the number, the configuration and the positions of double bonds. The methyl esters of linoleic and linolenic acid are not bitter. Gamma-linolenyl alcohol and alphalinolenic acid have the lowest threshold values (0.2–0.5 and 0.6–1.2 mmol/l), similar to that of caffeine (0.8–1.2 mmol/l).相似文献
78.
79.
Werner Heimann und Verena Klaiber 《Zeitschrift für Lebensmitteluntersuchung und -Forschung A》1977,165(3):131-136
Zusammenfassung Die Untersuchung einer aus Roggen gewonnenen Lipoxygenase-aktiven Enzymfraktion ergab, daß Roggenlipoxygenase ein Molekulargewicht von ca. 102000 besitzt. Bei der isoelektrischen Fokussierung traten zwei Bandengruppen mit isoelektrischen Punkten zwischen 5,1–5,5 und 5,8–6,4 auf. Durch Ionenaustauschchromatographie konnten drei Isoenzyme gewonnen werden. Das pH-Optimum der Umsetzung lag bei 7,3–7,5. Roggenlipoxygenase katalysiert vorwiegend die Bildung von 13-Hydroperoxy-9-cis,11-trans-octadecadiensäure (13-LHPO). Durch eine hochmolekulare Proteinfraktion wurden in Roggen die LHPO zu a-Ketolen umgesetzt. Diese Roggenisomerase setzt die von der systemeigenen Lipoxygenase gebildeten LHPO zu überwiegend 12,13-Ketohydroxysduren um. Roggenisomerase hat eine Michaeliskonstante von 3–5 × 10–5, (LHPO). Die Reaktionsgeschwindigkeit der Umsetzung stieg bei kleinen Proteinkonzentrationen linear mit der Proteinkonzentration.
On lipoxygenase and enzymes which decompose linoleic acid hydroperoxides in rye
Summary An enzyme fraction from rye containing lipoxygenase activity was investigated. The molecular weight of lipoxygenase was found to be about 102000. Two bands groups with isoelectric points between 5.1–5.5 and 5.8–6.4 were obtained by isoelectric focusing. Three isoenzymes could be separated by ion exchange chromatography. Lipoxygenase has optimum activity at pH 7.3–7.5 and predominantly forms 13-hydroperoxy-9-cis,11-trans-octadecadienoic acid (13-LHPO).In rye the 13-LHPO is converted to -ketols by a high molecular protein fraction. This isomerase converts the LHPO formed by rye lipoxygenase predominantly to 12,13-ketohydroxy acids. The Michaelis Constant of isomerase is 3–5 × 10–5, using LHPO as substrate. At low protein concentrations the reaction velocity of LHPO-conversion increases linearly with protein concentration.相似文献
80.
Adrian D. Werner Qi Zhang Lijuan Xue Brian D. Smerdon Xianghu Li Xinjun Zhu Lei Yu Ling Li 《Water Resources Management》2013,27(2):507-533
The state of groundwater systems worldwide is presently not well defined, and in particular there is little context for agencies responsible for managing water resources to evaluate occurrences of groundwater depletion against other cases globally. In this study, an initial inventory of groundwater depletion problems is compiled and ranked to identify the world’s most critical cases, i.e. situations of groundwater mega-depletion. The ranking is based on an indexed approach that considers overdraft, drawdown and subsidence, plus the importance of the resources in terms of population-dependency and rates of extraction. The five most highly ranked depleted aquifers of the world include the shallow aquifers of the Hai River Plain (China), the Altiplano region (Spain), the Mexico Basin (Mexico), the Huang River basin (China) and the California Central Valley (USA). An abridged account of modelling to assess drawdown is described for the Hai River Plain, revealing that despite recharge in the order of 13,000 GL/yr, an overdraft of about 8,000 GL/yr is occurring to support the vast population of the region. This has led to up to 100 m of drawdown in places and reports of subsidence of several metres. The Hai River situation demonstrates that falling water levels may not act to alleviate pumping stresses; a symptom of unchecked extraction and an exemplary illustration of the tragedy of the commons. The causal factors leading to mega-depletion are varying across the globe and each mega-depletion case contains unique elements, although population appears to be an important factor. 相似文献