bluuebunny/crossref_metadata_2025_split huggingface dataset:
Generating compiler optimizations from proofs
Authors: Tate Ross , Stepp Michael , Lerner Sorin 
Published: January 2010

We present an automated technique for generating compiler optimizations from examples of concrete programs before and after improvements have been made to them. The key technical insight of our technique is that a proof of equivalence between the original and transformed concrete programs informs us which aspects of the programs are important and which can be discarded. Our technique therefore uses these proofs, which can be produced by translation validation or a proof-carrying compiler, as a guide to generalize the original and transformed programs into broadly applicable optimization rules.
We present a category-theoretic formalization of our proof generalization technique. This abstraction makes our technique applicable to logics besides our own. In particular, we demonstrate how our technique can also be used to learn query optimizations for relational databases or to aid programmers in debugging type errors.
Finally, we show experimentally that our technique enables programmers to train a compiler with application-specific optimizations by providing concrete examples of original programs and the desired transformed programs. We also show how it enables a compiler to learn efficient-to-run optimizations from expensive-to-run super-optimizers.
Semantics and algorithms for data-dependent grammars
Authors: Jim Trevor , Mandelbaum Yitzhak , Walker David 
Published: January 2010

We present the design and theory of a new parsing engine, YAKKER, capable of satisfying the many needs of modern programmers and modern data processing applications. In particular, our new parsing engine handles (1) full scannerless context-free grammars with (2) regular expressions as right-hand sides for defining nonterminals. YAKKER also includes (3) facilities for binding variables to intermediate parse results and (4) using such bindings within arbitrary constraints to control parsing. These facilities allow the kind of data-dependent parsing commonly needed in systems applications, particularly those that operate over binary data. In addition, (5) nonterminals may be parameterized by arbitrary values, which gives the system good modularity and abstraction properties in the presence of data-dependent parsing. Finally, (6) legacy parsing libraries,such as sophisticated libraries for dates and times, may be directly incorporated into parser specifications. We illustrate the importance and utility of this rich collection of features by presenting its use on examples ranging from difficult programming language grammars to web server logs to binary data specification. We also show that our grammars have important compositionality properties and explain why such properties areimportant in modern applications such as automatic grammar induction.
In terms of technical contributions, we provide a traditional high-level semantics for our new grammar formalization and show how to compile grammars into non deterministic automata. These automata are stack-based, somewhat like conventional push-down automata,but are also equipped with environments to track data-dependent parsing state. We prove the correctness of our translation of data-dependent grammars into these new automata and then show how to implement the automata efficiently using a variation of Earley's parsing algorithm.
Modular verification of security protocol code by typing
Authors: Bhargavan Karthikeyan , Fournet Cédric , Gordon Andrew D. 
Published: January 2010

We propose a method for verifying the security of protocol implementations. Our method is based on declaring and enforcing invariants on the usage of cryptography. We develop cryptographic libraries that embed a logic model of their cryptographic structures and that specify preconditions and postconditions on their functions so as to maintain their invariants. We present a theory to justify the soundness of modular code verification via our method.
We implement the method for protocols coded in F# and verified using F7, our SMT-based typechecker for refinement types, that is, types carrying formulas to record invariants. As illustrated by a series of programming examples, our method can flexibly deal with a range of different cryptographic constructions and protocols.
We evaluate the method on a series of larger case studies of protocol code, previously checked using whole-program analyses based on ProVerif, a leading verifier for cryptographic protocols. Our results indicate that compositional verification by typechecking with refinement types is more scalable than the best domain-specific analysis currently available for cryptographic code.
Failure of Postnatal Ductus Arteriosus Closure in Prostaglandin Transporter–Deficient Mice
Authors: Chang Hee-Yoon , Locker Joseph , Lu Run , Schuster Victor L. 
Published: January 2010

Background—Prostaglandin E2(PGE2) plays a major role both in maintaining patency of the fetal ductus arteriosus and in closure of the ductus arteriosus after birth. The rate-limiting step in PGE2signal termination is PGE2uptake by the transporter PGT.Methods and Results—To determine the role of PGT in ductus arteriosus closure, we used a gene-targeting strategy to produce mice in which PGT exon 1 was flanked by loxP sites. Successful targeting was obtained because neither mice hypomorphic at the PGT allele (PGT Neo/Neo) nor global PGT knockout mice (PGT−/−) exhibited PGT protein expression; moreover, embryonic fibroblasts isolated from targeted mice failed to exhibit carrier-mediated PGE2uptake. Although born in a normal mendelian ratio, no PGT−/−mice survived past postnatal day 1, and no PGT Neo/Neo mice survived past postnatal day 2. Necropsy revealed patent ductus arteriosus with normal intimal thickening but dilated cardiac chambers. Both PGT Neo/Neo and PGT−/−mice could be rescued through the postnatal period by giving the mother indomethacin before birth. Rescued mice grew normally and had no abnormalities by gross and microscopic postmortem analyses. In accordance with the known role of PGT in metabolizing PGE2, rescued adult PGT−/−mice had lower plasma PGE2metabolite levels and higher urinary PGE2excretion rates than wild-type mice.Conclusion—PGT plays a critical role in closure of the ductus arteriosus after birth by ensuring a reduction in local and/or circulating PGE2concentrations.
Bibliotheca frisica juridica III Bio-bibliografische notities over enkele weinig bekende Friese juristen Bibliotheca Frisica juridica III, Bio-bibliographical notes on some little known Frisian jurists
Authors: Feenstra R. 
Published: January 2010

AbstractThird part of a series on some early Frisian jurists who have left printed editions of their works (for the first part see TR 75 (2007), p. 125–137, for the second part see TR 76 (2008), p. 329–351). The present contribution deals with Franciscus Meinardus (1569/1570–1623), teaching as a licentiatus in Angers and professor in Poitiers, and with Dominicus Arumaeus (1579–1637), professor in Jena and one of the founders of the German science of public law. At the end some corrections and additions regarding the notes on Haring Sinnema (in part I), Joachimus Hopperus (in part II) and Thomas Herbaius (also in part II).
Hugo Grotius and the Thirty Years War, An early reception of De iure belli ac pacis
Authors: Müller Edgar 
Published: January 2010

AbstractIt is generally assumed that the peace negotiations at Münster and Osnabrück were influenced by the Spanish authors of the so-called Second Scholastics such as Francisco Suarez and Francisco de Vitoria, although evidence of that influence is lacking. It is possible, however, to establish that Grotius's book on the law of war and peace did influence the Westphalian negotiations. De iure belli et pacis was first published in 1625; it was widely read and during the 1630s it was used for teaching purposes in the universities of Strasbourg, Tübingen, Ingolstadt and Uppsala.
Formation of Jets through Mixing and Forcing of Potential Vorticity: Analysis and Parameterization of Beta-Plane Turbulence
Authors: Nakamura Noboru , Zhu Da 
Published: January 2010

Abstract
Formation of multiple jets in forced beta-plane turbulence is studied from the perspective of nonuniform nonconservative arrangement of potential vorticity (PV). Numerical simulations are analyzed to show that mixing and forcing reinforce jets by concentrating PV gradients at the axes of prograde jets. Based on the formalism developed in the companion paper, the nonconservative driving of jets is diagnosed and parameterized through the diffusive flux of PV and the source of wave activity. It is found that the two terms nearly balance on a long time scale, and they are both strongly anticorrelated with the PV gradient, which suggests that PV controls the nonconservative processes and that these processes could be parameterized as functions of the PV gradient. The flux is modeled using the effective diffusivity formula recently obtained by Ferrari and Nikurashin. Consistent with the PV barrier concept, the nonlinear diffusivity is a decreasing function of the squared PV gradient and agrees well with the diffusivity diagnosed from the numerical simulation. The source term is assumed to be inversely proportional to the PV gradient. The parameterization gives rise to a nonlinear partial differential equation (PDE) for the mean flow. A finite-difference model of the PDE predicts formation of a piecewise linear PV (staircase) and piecewise parabolic jets from a near-uniform initial condition when anisotropy and mixing of the flow are sufficiently strong. The origin of the discontinuities is antidiffusive instability of PV gradients, and although nonlinearity allows the discrete model to integrate stably, the solution is sensitive to the initial condition and resolution. The emerging jets in the 1D model have similar characteristics to those in the numerical simulation, but the details of the transient behavior are distinct. Similar discrete models of ill-posed PDEs in which discontinuities form also appear in image processing and granular matter dynamics.
Validation of Surface Current Measurements in the Northern Adriatic Sea from High-Frequency Radars
Authors: Cosoli Simone , Mazzoldi Andrea , Gačić Miroslav 
Published: January 2010

Abstract
The performances of a shore-based high-frequency (HF) radar network deployed along the coast of the Venice lagoon (northern Adriatic Sea) are discussed based on a comparison with a single bottom-mounted ADCP deployed in the shallow-water area offshore of the lagoon for a 40-day period in August–September 2005.
The analyses, carried out using currents representative of the first meter for the HF radars and 2.5 m for the ADCP, gave rms differences of radial currents in the range of 8.7–14.7 cm s−1 (correlation 0.37– 0.82) for the ideal pattern and 8.4–20.5 cm s−1 (correlation 0.14–0.84) for the measured pattern. Good correlation was found between surface current vectors and moored data (scalar correlation up to R = 0.83, vector correlation ρ = 0.78, veering angle 6°). Comparison metrics were improved for the low-passed currents. Angular offsets ranged between +6° and +11°. Differences depended primarily on the geophysical variability within the water column. Bearing offsets also contributed because they lead to comparisons with radial velocities at erroneous angular sectors.
Radar performances were severely affected by strong northeasterly wind pulses in their early stages. An increased broadband noise, spread over the entire Doppler spectrum across all ranges to the antennas, masked the Bragg peaks and determined the loss in radar coverage, introducing gross underestimations of both radial velocities and total currents.
A Synoptic Weather Typing Approach to Simulate Daily Rainfall and Extremes in Ontario, Canada: Potential for Climate Change Projections
Authors: Cheng Chad Shouquan , Li Guilong , Li Qian , Auld Heather 
Published: January 2010

Abstract
An automated synoptic weather typing and stepwise cumulative logit/nonlinear regression analyses were employed to simulate the occurrence and quantity of daily rainfall events. The synoptic weather typing was developed using principal component analysis, an average linkage clustering procedure, and discriminant function analysis to identify the weather types most likely to be associated with daily rainfall events for the four selected river basins in Ontario. Within-weather-type daily rainfall simulation models comprise a two-step process: (i) cumulative logit regression to predict the occurrence of daily rainfall events, and (ii) using probability of the logit regression, a nonlinear regression procedure to simulate daily rainfall quantities. The rainfall simulation models were validated using an independent dataset, and the results showed that the models were successful at replicating the occurrence and quantity of daily rainfall events. For example, the relative operating characteristics score is greater than 0.97 for rainfall events with daily rainfall ≥10 or ≥25 mm, for both model development and validation. For evaluation of daily rainfall quantity simulation models, four correctness classifications of excellent, good, fair, and poor were defined, based on the difference between daily rainfall observations and model simulations. Across four selected river basins, the percentage of excellent and good simulations for model development ranged from 62% to 84% (of 20 individuals, 16 cases ≥ 70%, 7 cases ≥ 80%); the corresponding percentage for model validation ranged from 50% to 76% (of 20 individuals, 15 cases ≥ 60%, 6 cases ≥ 70%).
Snow Studies. Part I: A Study of Natural Variability of Snow Terminal Velocity
Authors: Zawadzki Isztar , Jung Eunsil , Lee Gyowon 
Published: January 2010

Abstract
The variability and the uncertainties in snowfall velocity measurements are addressed in this study. The authors consider (i) the instrumental uncertainty in the fall velocity measurement, (ii) the effect of unstable falling motion on the accuracy of velocity measurement, and (iii) the natural variability of homogeneous snow terminal fall velocity. It is shown that, when periods of homogeneous characteristics of snow are selected to minimize the mixture of particles of different origin, the standard deviation of snowfall velocity within each period tends to stabilize at a value between 0.1 and 0.2 m s−1.
In addition, the variability of snow terminal fall velocity is examined with three control variables: surface temperature Ts, echo-top temperature Tt, and the depth of precipitation system H. The results show that the exponent b in the power-law relationship V = aDb has little effect on the variability of snowfall velocity: the coefficient a correlates much better with the control variables (Ts, Tt, H) than the exponent b. Hence, snowfall velocity can be modeled with a varying coefficient a and a fixed exponent b = 0.18 (V = aD0.18) with good accuracy.
Observed Self-Similarity of Precipitation Regimes over the Tropical Oceans
Authors: Elsaesser Gregory S. , Kummerow Christian D. , L’Ecuyer Tristan S. , Takayabu Yukari N. , Shige Shoichi 
Published: January 2010

Abstract
A K-means clustering algorithm was used to classify Tropical Rainfall Measuring Mission (TRMM) Precipitation Radar (PR) scenes within 1° square patches over the tropical (15°S–15°N) oceans. Three cluster centroids or “regimes” that minimize the Euclidean distance metric in a five-dimensional space of standardized variables were sought [convective surface rainfall rate; ratio of convective rain to total rain; and fractions of convective echo profiles with tops in three fixed height ranges (&lt;5, 5–9, and &gt;9 km)]. Independent cluster computations in adjacent ocean basins return very similar clusters in terms of PR echo-top distributions, rainfall, and diabatic heating profiles. The clusters consist of shallow convection (SHAL cluster), with a unimodal distribution of PR echo tops and composite diabatic heating rates of ∼2 K day−1 below 3 km; midlevel convection (MID-LEV cluster), with a bimodal distribution of PR echo tops and ∼5 K day−1 heating up to about 7 km; and deeper convection (DEEP cluster), with a multimodal distribution of PR echo tops and &gt;20 K day−1 heating from 5 to 10 km. Each contributes roughly 20%–40% in terms of total tropical rainfall, but with MID-LEV clusters especially enhanced in the Indian and Atlantic sectors, SHAL relatively enhanced in the central and east Pacific, and DEEP most prominent in the western Pacific. While the clusters themselves are quite similar in rainfall and heating, specific cloud types defined according to the PR echo top and surface rainfall rate are less similar and exhibit systematic differences from one cluster to another, implying that the degree to which precipitation structures are similar decreases when one considers individual precipitating clouds as repeating tropical structures instead of larger-scale cluster ensembles themselves.
Deep Equatorial Ocean Circulation Induced by a Forced–Dissipated Yanai Beam*
Authors: Ascani François , Firing Eric , Dutrieux Pierre , McCreary Julian P. , Ishida Akio 
Published: January 2010

Abstract
A complex pattern of zonal currents below the thermocline has been observed in the equatorial Pacific and Atlantic Oceans. The currents have typical speeds from 10 to 15 cm s−1 and extend as deep as 2500 m. Their structure can be divided into two overlapping parts: the equatorial deep jets (EDJs), centered on the equator and alternating in the vertical with a wavelength of several hundred meters, and the Equatorial Intermediate Current system (EICS), composed of currents with large vertical scale and alternating with latitude over several degrees on either side of the equator. The strongest EICS current is a westward flow on the equator flanked by eastward currents at 2°N and 2°S.
In the present study, the authors use idealized numerical simulations and analytical solutions to demonstrate that the EICS currents within 2.5° from the equator could result from the self-advection with dissipation of a downward-propagating beam of monthly periodic Yanai (Rossby gravity) waves. The zonally restricted beam is generated in the eastern part of the basin by instabilities of the swift near-surface equatorial currents. For a weak Yanai wave amplitude and no dissipation, mean Eulerian currents resembling the three strongest EICS currents are obtained but only within the beam; in this case, the Eulerian flow is balanced by the wave-induced Stokes drift, yielding a zero-mean Lagrangian flow, and the water parcels conserve their potential vorticity (PV) and are stationary over a wave cycle. For larger amplitudes, the Yanai waves break, losing their energy to small vertical scales where it is dissipated. This dissipation changes the mean (wave averaged) PV of a water parcel within the beam, allowing the parcel to have a persistent equatorward drift across PV contours. This can be viewed as a wave-induced Sverdrup transport; by continuity and by virtue of the westward group velocity of long Rossby waves, this Lagrangian-mean meridional flow requires a Lagrangian-mean zonal flow within and to the west of the beam, with a meridional structure consistent with the three strongest EICS currents. This mechanism of EICS formation is active in some ocean general circulation models; its importance in the ocean remains to be evaluated.
Simultaneous Observations of Thin Humidity Gradients in the Lower Troposphere with a Raman Lidar and the Very High-Frequency Middle- and Upper-Atmosphere Radar
Authors: Luce H. , Takai T. , Nakamura T. , Yamamoto M. , Fukao S. 
Published: January 2010

Abstract
Humidity is, among other things, a key parameter in the evolution of atmospheric dynamics and in the formation of clouds and precipitation through latent heat release. The continuous observation of its vertical distribution is thus important in meteorology. In the absence of convection, humidity in the lower troposphere is distributed into nearly horizontally stratified layers. The thin humidity gradients at the edges of these layers are known to be the main cause of very high-frequency (VHF) stratosphere–troposphere (ST) radar backscatter in the lower troposphere. This property has been experimentally demonstrated many times in the literature from comparisons between balloon measurements and low-resolution radar observations. In the present work, original results of comparisons between Raman lidar measurements of water vapor and middle- and upper-atmosphere (MU) radar measurements of echo power using a range-imaging technique are shown at high spatial and temporal resolutions (∼50 m, ∼20 s). Other tremendous advantages of such comparisons are the simultaneity, time continuity, and colocalization of the lidar and radar measurements. The results show that the radar can be used for continuously monitoring the thin positive and negative gradients of humidity when operated in range-imaging mode. With additional information from balloon measurements, it would be possible to retrieve humidity profiles in the lower troposphere at an unprecedented vertical and time resolution.
Operational Monitoring of Radar Differential Reflectivity Using the Sun
Authors: Holleman Iwan , Huuskonen Asko , Gill Rashpal , Tabary Pierre 
Published: January 2010

Abstract
A method for the daily monitoring of the differential reflectivity bias for polarimetric weather radars is presented. Sun signals detected in polar volume data produced during operational scanning of the radar are used. This method is an extension of that for monitoring the weather radar antenna pointing at low elevations and the radar receiving chain using the sun. This “online” method is ideally suited for routine application in networks of operational radars.
The online sun monitoring can be used to check the agreement between horizontal and vertical polarization lobes of the radar antenna, which is a prerequisite for high-quality polarimetric measurements. By performing both online sun monitoring and rain calibration at vertical incidence, the differential receiver bias and differential transmitter bias can be disentangled. Results from the polarimetric radars in Trappes (France) and Bornholm (Denmark), demonstrating the importance of regular monitoring of the differential reflectivity bias, are discussed.
It is recommended that the online sun-monitoring method, preferably in combination with rain calibration, is routinely performed on all polarimetric weather radars because accurate calibration is a prerequisite for most polarimetric algorithms.