170,913 research outputs found
Abstraction Refinement Guided by a Learnt Probabilistic Model
No full textThe core challenge in designing an effective static program analysis is to find a good program abstraction -- one that retains only details relevant to a given query. In this paper, we present a new approach for automatically finding such an abstraction. Our approach uses a pessimistic strategy, which can optionally use guidance from a probabilistic model. Our approach applies to parametric static analyses implemented in Datalog, and is based on counterexample-guided abstraction refinement. For each untried abstraction, our probabilistic model provides a probability of success, while the size of the abstraction provides an estimate of its cost in terms of analysis time. Combining these two metrics, probability and cost, our refinement algorithm picks an optimal abstraction. Our probabilistic model is a variant of the Erdos-Renyi random graph model, and it is tunable by what we call hyperparameters. We present a method to learn good values for these hyperparameters, by observing past runs of the analysis on an existing codebase. We evaluate our approach on an object sensitive pointer analysis for Java programs, with two client analyses (PolySite and Downcast)
Tree Buffers
No full textIn runtime verification, the central problem is to decide if a given program execution violates a given property. In online runtime verification, a monitor observes a program’s execution as it happens. If the program being observed has hard real-time constraints, then the monitor inherits them. In the presence of hard real-time constraints it becomes a challenge to maintain enough information to produce error traces, should a property violation be observed. In this paper we introduce a data structure, called tree buffer, that solves this problem in the context of automata-based monitors: If the monitor itself respects hard real-time constraints, then enriching it by tree buffers makes it possible to provide error traces, which are essential for diagnosing defects. We show that tree buffers are also useful in other application domains. For example, they can be used to implement functionality of capturing groups in regular expressions. We prove optimal asymptotic bounds for our data structure, and validate them using empirical data from two sources: regular expression searching through Wikipedia, and runtime verification of execution traces obtained from the DaCapo test suite
Grigore C. Moisil: A Life Becoming a Myth
No full textGrigore C. Mosil, Romanian mathematician, Professor at the University of Bucharest - Faculty of Mathematicsand Computer Science, member of the Romanian Academy, member of the Academy of Sciencesin Bologna and of the International Institute of Philosophy, Computer Pioneer Award of IEEE ComputerSociety (IEEE - 1996)
Characterization of the Paint from “The Lord’s Transfiguration” Icon by Grigore Ranite
No full text“The Lord’s Transfiguration” icon painted by Grigore Ranite belongs to a collection of altarpiece icons from the Ethnographic Museum of Transylvania. The aim of this paper is to present the results obtained from the scientific investigations carried out to establish the materials and methods used by the painter for the accomplishment of the religious art work, both for conservation and restoration purposes, as well as to enrich the knowledge about the work of this particular author and about the Transylvanian iconography in general. The analyses were performed by means of X-ray fluorescence (XRF) spectroscopy and destructive and nondestructive Fourier transform infrared (FTIR) spectroscopy.</p
Legea pentru încurajarea construirii de locuinţe
No full textBucureşti : Institutul de Arte Grafice şi Editură "Curierul Judiciar", 1927. - 132 p. ; 21 cm. - (Biblioteca legilor uzuale adnotate ; No. 8 ). - Mai cuprinde: Expunerea de motive a ministrului muncii [Grigore L. Trancu-Iaşi] ; Avizul Consiliului legislativ ; Raportul senatorului G. Văleanu ; Raportul deputatului Braiesku ; Instrucţiuni date de Ministerul de finanţe cu Circulara No. 131.688 din 23 mai 192
Ion Sircu. Muntii Rodnéi, studiu morfogeografic ; Ionita Ichim. Muntii Stinisoara, studiu geomorfologic ; Mihai Grigore. Muntii Somenic, potentialul relief ului ; C. Brandus. Subcarpatii Tazlaului, studiu geomorfologic
No full textGuilcher André. Ion Sircu. Muntii Rodnéi, studiu morfogeografic ; Ionita Ichim. Muntii Stinisoara, studiu geomorfologic ; Mihai Grigore. Muntii Somenic, potentialul relief ului ; C. Brandus. Subcarpatii Tazlaului, studiu geomorfologic. In: Norois, n°113, Janvier-Mars 1982. pp. 183-184
Going Beyond Counting First Authors in Author Co-citation Analysis
No full textThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
GRIGORE H. GRANDEA: POLITICS, JOURNALISM AND WAR
No full textGrigore H. Grandea was one of the most important and influential Romanian journalists and publishers. He outlined in his biography that he was Lord Byron’s grandson, but this is false. Grandea worked for several important publications such as Dâmboviţa, Albina Pindului, Timpul and Războiul. He was appreciated by Mihai Eminescu and mocked by Titu Maiorescu. At Timpul, Grandea worked with Ioan Slavici, another prominent journalist and publisher, and this happened just before Eminescu joined the editorial staff. Grandea’s most important realisation was the daily gazette Războiul, the most powerful newspaper of its days. Războiul had at a certain point a circulation of 15 000 to 18 000 copies per day, compared to Timpul, which had a circulation between 3 000 and 6 000 copies per day. Grandea polemized with the representatives of the Liberal Party, at the time being in power, and especially with C. A. Rosetti, political leader and publisher at the daily newspaper Românul
High density lipoprotein cholesterol levels are an independent predictor of the progression of chronic kidney disease
No full textObjectives: Patients with chronic kidney disease (CKD) often present with reduced plasma HDL cholesterol (HDL-C) levels. Whether this reduction in an epiphenomenon or is involved in disease progression is unclear. The aim of this study was to investigate the relation between HDL-C levels/function and CKD progression in patients with different degrees of disease. Design: A total of 176 patients with CKD [glomerular filtration rate (GFR) 50.3 ± 29.1 mL min-1] were recruited and followed for up to 84 months. Lipid profile, metabolic status and kidney function were evaluated at predetermined times. Age-matched control subjects were selected from the PLIC study (n = 453). Scavenger receptor class B member 1 (SR-BI) and ATP-binding cassette transporter A1 (ABCA-1)-dependent efflux of cholesterol were measured in CKD patients and in age-matched control subjects. Results: Low HDL-C levels, diabetes and hypertension were associated with reduced GFR. At follow-up, low HDL-C levels were associated with earlier entry in dialysis or doubling of the plasma creatinine level (P = 0.017); HDL-C levels were the only lipid parameter that affected the progression of CKD (hazard ratio 0.951, 95% confidence interval 0.917-0.986, P = 0.007), independently of the presence of diabetes. Only SR-BI-mediated serum cholesterol efflux was significantly reduced in the group of CKD patients with low HDL-C levels compared to the control group. Conclusions: CKD patients with low levels of plasma HDL-C have a poor prognosis. HDL functionality is also impaired in renal dysfunction. These data support the relevance of HDL in influencing CKD progression
Analysis of the electrical and thermal behaviour of Li-ion batteries using 0D and 3D-CFD approaches with validation on experimental data
No full textDue to their characteristics, lithium-ion cells are the reference in the construction of a
battery pack for electric vehicles (EVs). Despite this, their use is strongly affected by the
operating temperature because the materials they are made of are thermally stable only in a
relatively limited range around ambient temperature. Cell modelling and simulation become
therefore essential in the design of the cell, of the battery pack and of its auxiliary systems to
optimize performance while maintaining sufficient safety margins.
In the present study, two zero-dimensional equivalent circuit models of a commercial Li-ion cell
are developed and tuned in order to predict the electrical and thermal behaviour of the cell. The
models are validated and compared with experimental data found in the scientific literature
referring to both dynamic and static tests. This comparison shows the importance of tuning the
model parameters, which are decisive for the accuracy of the simulation.
Using a commercial tool dedicated to battery modelling, a three-dimensional model is then
developed to investigate the electrical and thermal behaviour of the cell from a spatial point of
view. The results obtained are aligned with those found in the scientific literature.
With the present work, it has been possible to simulate and analyse the global behaviour of the
cell (0D model) as well as its detailed behaviour (3D model) using relatively modest
computational resources, thus constituting a solid base for more complex modelling such as that
of a battery pack and its cooling system
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