Analysis of an OpenMP Program for Race Detection

The race condition in a shared memory parallel program is subtle and harder to find than in a sequential program. The race conditions cause non-deterministic and unexpected results from the program. It should be avoided in the parallel region of OpenMP programs. The proposed OpenMP Race Avoidance Tool statically analyzes the parallel region. It gives alerts regarding possible data races in that parallel region. The proposed tool has the capability to analyze the basic frequently occurring non-nested ‘for loop(s)’. We are comparing the results of the proposed tool with the commercially available static analysis tool named Intel Parallel Lint and the dynamic analysis tool named Intel Thread Checker for race detection in OpenMP program. The proposed tool detects race conditions in the ‘critical’ region that have not been detected by existing analysis tools. The proposed tool also detects the race conditions for the ‘atomic’, ‘parallel’, ‘master’, ‘single’ and ‘barrier’ constructs. The OpenMP beginner programmers can use this tool to understand how to create a shared-memory parallel program

Thread-Modular Static Analysis by Abstract Interpretation: designing relational abstractions of interferences

International audienceIn this document, we use the Abstract Interpretation framework to analyze concurrent programs using Thread-Modular Analysis. We designed a relational abstraction of interferences in order to infer more properties and go beyond the state of the art. We implemented a basic analyzer, studying the numerical properties of a simple language. We present the results obtained, as well as a study of the scalability of this approach

Optical studies of gap, hopping energies and the Anderson-Hubbard parameter in the zigzag-chain compound SrCuO2

We have investigated the electronic structure of the zigzag ladder (chain) compound SrCuO2 combining polarized optical absorption, reflection, photoreflectance and pseudo-dielectric function measurements with the model calculations. These measurements yield an energy gap of 1.42 eV (1.77 eV) at 300 K along (perpendicular) to the Cu-O chains. We have found that the lowest energy gap, the correlation gap, is temperature independent. The electronic structure of this oxide is calculated using both the local-spin-density-approximation with gradient correction method, and the tight-binding theory for the correlated electrons. The calculated density of electronic states for non-correlated and correlated electrons shows quasi-one-dimensional character. The correlation gap values of 1.42 eV (indirect transition) and 1.88 eV (direct transition) have been calculated with the electron hopping parameters t = 0.30 eV (along a chain), t_yz = 0.12 eV (between chains) and the Anderson-Hubbard repulsion on copper sites U= 2.0 eV. We concluded that SrCuO_2 belongs to the correlated-gap insulators.Comment: 24 pages, 8 figures, to be published in Phys.Rev.

Linear Haskell: practical linearity in a higher-order polymorphic language

Linear type systems have a long and storied history, but not a clear path forward to integrate with existing languages such as OCaml or Haskell. In this paper, we study a linear type system designed with two crucial properties in mind: backwards-compatibility and code reuse across linear and non-linear users of a library. Only then can the benefits of linear types permeate conventional functional programming. Rather than bifurcate types into linear and non-linear counterparts, we instead attach linearity to function arrows. Linear functions can receive inputs from linearly-bound values, but can also operate over unrestricted, regular values. To demonstrate the efficacy of our linear type system - both how easy it can be integrated in an existing language implementation and how streamlined it makes it to write programs with linear types - we implemented our type system in GHC, the leading Haskell compiler, and demonstrate two kinds of applications of linear types: mutable data with pure interfaces; and enforcing protocols in I/O-performing functions

Formal methods and tools for the development of distributed and real time systems : Esprit Project 3096 (SPEC)

The Basic Research Action No. 3096, Formal Methods snd Tools for the Development of Distributed and Real Time Systems, is funded in the Area of Computer Science, under the ESPRIT Programme of the European Community. The coordinating institution is the Department of Computing Science, Eindhoven University of Technology, and the participating Institutions are the Institute of Computer Science of Crete. the Swedish Institute of Computer Science, the Programmimg Research Group of the University of Oxford, and the Computer Science Departments of the University of Manchester, Imperial College. Weizmann Institute of Science, Eindhoven University of Technology, IMAG Grenoble. Catholic University of Nijmegen, and the University of Liege. This document contains the synopsis. and part of the sections on objectives and area of advance, on baseline and rationale, on research goals, and on organisation of the action, as contained in the original proposal, submitted June, 198S. The section on the state of the art (18 pages) and the full list of references (21 pages) of the original proposal have been deleted because of limitation of available space

A Stochastic Pi Calculus for Concurrent Objects

International audienceWe present SpiCO, a new modeling and simulation language for system biology, based on the stochastic pi-calculus. SpiCO supports higher level modeling via multi-profile concurrent objects with static inheritance. We present a semantics for SpiCO in terms of continuous time Markov chains, and show how to compile SpiCO back into the biochemical stochastic pi-calculus while preserving semantics

Employment effects of the provision of specific professional skills and techniques in Germany

"Based on unique administrative data, which has only recently become available, this paper estimates the employment effects of the most important type of public sector sponsored training in Germany, namely the provision of specific professional skills and techniques (SPST). Using the inflows into unemployment for the year 1993, the empirical analysis uses local linear matching based on the estimated propensity score to estimate the average treatment effect on the treated of SPST programs starting during 1 to 6, 7 to 12, and 13 to 24 months of unemployment. The empirical results show a negative lock-in effect for the period right after the beginning of the program and significantly positive treatment effects on employment rates of about 10 percentage points and above a year after the beginning of the program. The general pattern of the estimated treatment effects is quite similar for the three time intervals of elapsed unemployment considered. The positive effects tend to persist almost completely until the end of our evaluation period. The positive effects are stronger in West Germany compared to East Germany." (Author's abstract, IAB-Doku) ((en))IAB-Beschäftigtenstichprobe, IAB-Leistungsempfängerhistorik, prozessproduzierte Daten, Weiterbildungsförderung - Erfolgskontrolle, Arbeitslosigkeitsdauer, berufliche Reintegration, Arbeitslose, Beschäftigungseffekte, Westdeutschland, Ostdeutschland, Bundesrepublik Deutschland