1,552 research outputs found

    Why Just Boogie? Translating Between Intermediate Verification Languages

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    The verification systems Boogie and Why3 use their respective intermediate languages to generate verification conditions from high-level programs. Since the two systems support different back-end provers (such as Z3 and Alt-Ergo) and are used to encode different high-level languages (such as C# and Java), being able to translate between their intermediate languages would provide a way to reuse one system's features to verify programs meant for the other. This paper describes a translation of Boogie into WhyML (Why3's intermediate language) that preserves semantics, verifiability, and program structure to a large degree. We implemented the translation as a tool and applied it to 194 Boogie-verified programs of various sources and sizes; Why3 verified 83% of the translated programs with the same outcome as Boogie. These results indicate that the translation is often effective and practically applicable

    The rate of the prevalence of high-risk pregnancies and the results on pregnant mothers and the effect on parameters after the birth

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    Pregnancy causes large physiologic changes in most body systems and these changes may lead to ease or harden examining some events. The purpose of this study is to define the rate of risk in pregnant women and the results in mother and fetus and also to define the risk rate of pregnancy in pregnant women and its effect on parameters after birth in patients of Educational and Medical center of Gorgan, Dezyani. This case - control study was performed in Educational and Medical Center Dezyany, of Golestan University of Medical Sciences in 1390. In this study, 1266 pregnant women were enrolled of which 804 cases (63.5%) according to the criteria for scoring in the questionnaire with a score greater than or equal to 7 were considered as high risk pregnancies (case group), 462 patients (36.5%) were considered as low-risk pregnancies (control group). Parameters after the birth and pregnancy results such as delivery type, infant difficulties, mother health after labor were compared and analyzed by T-test and ANOVA in both groups. About the history of infertility almost 80% of the people who had a 2-year history of infertility were in high-risk group and the difference was significant. (P = 0.02) About the history of abortion also almost 90% of the people who had a 2-year history of abortion were in highrisk group and the difference was significant. (P<0.05) Post-term infant was found in 77 cases that were entirely in high-risk group. This difference was statistically significant (P<0.05). According to results and comparing them to other studies we can conclude that pregnant mothers who have pregnancy difficulties history such as history of abortion or infertility, visits during pregnancy should be paid attention and warn them about the risk of not being visited and timely pursuits

    Navier-Stokes turbine heat transfer predictions using two-equation turbulence

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    Navier-Stokes calculations were carried out in order to predict the heat transfer rates on turbine blades. The calculations were performed using TRAF2D which is a two-dimensional, explicit, finite volume mass-averaged Navier-Stokes solver. Turbulence was modeled using q-omega and k-epsilon two-equation models and the Baldwin-Lomax algebraic model. The model equations along with the flow equations were solved explicitly on a non-periodic C grid. Implicit residual smoothing (IRS) or a combination of multigrid technique and IRS was applied to enhance convergence rates. Calculations were performed to predict the Stanton number distributions on the first stage vane and blade row as well as the second stage vane row of the Rocketdyne Space Shuttle Main Engine (SSME) high pressure fuel turbine. The comparison with the experimental results, although generally favorable, serves to highlight the weaknesses of the turbulence models and the possible areas of improving these models for use in turbomachinery heat transfer calculations

    The low KM-phosphodiesterase inhibitor denbufylline enhances neuronal excitability in guinea pig hippocampus in vitro

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    The actions of the phosphodiesterase inhibitor denbufylline on the excitability of hippocampal neurons were investigated by means of extracellular and intracellular recordings. Denbufylline, which has been shown to selectively inhibit a low KM, Ca2+/calmodulin-independent phosphodiesterase isozyme, concentration-dependently increased the amplitude of the extracellularly recorded CAI population spike evoked by electrical stimulation of the Schaffer collateral/commissural pathway. Concentration-response-curves yielded an EC50 for denbufylline of 0.76 M. In comparison, the nonselective phosphodiesterase inhibitor 3-isobutyl-lmethylxanthine (IBMX) also produced an increase in the amplitude of the population spike. From the concentration-response-curve, which was steeper than that of denbufylline, an EC50 for IBMX of 1.04 M was obtained. However, despite their similar EC50 values, denbufylline was found to be significantly more potent at lower concentrations (<- 300 nM) than IBMX. Intracellular recordings from CAI pyramidal cells revealed postsynaptic actions of denbufylline (300 nM) as indicated by a small drug-induced depolarization (2 – 5 mV) associated with an increase in membrane input resistance by 10–20%. In addition, denbufylline blocked the accommodation of trains of action potentials evoked by the injection of depolarizing current pulses. The results suggest i) that accumulation of adenosine-3,5-monophosphate (CAMP) in the postsynaptic cell and/or in the presynaptic terminal produced by blockade of phosphodiesterases leads to enhanced synaptic transmission in the CAI area of the hippocampus and ii) that a low KM, Ca 2+/calmodulin-independent cAMP-phosphodiesterase is an important component involved in the regulation of the intracellular cAMP level at synapses of central nervous system neurons

    Implementation of a Transition Model in a NASA Code and Validation Using Heat Transfer Data on a Turbine Blade

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    The purpose of this report is to summarize and document the work done to enable a NASA CFD code to model laminar-turbulent transition process on an isolated turbine blade. The ultimate purpose of the present work is to down-select a transition model that would allow the flow simulation of a variable speed power turbine to be accurately performed. The flow modeling in its final form will account for the blade row interactions and their effects on transition which would lead to accurate accounting for losses. The present work only concerns itself with steady flows of variable inlet turbulence. The low Reynolds number k- model of Wilcox and a modified version of the same model will be used for modeling of transition on experimentally measured blade pressure and heat transfer. It will be shown that the k- model and its modified variant fail to simulate the transition with any degree of accuracy. A case is thus made for the adoption of more accurate transition models. Three-equation models based on the work of Mayle on Laminar Kinetic Energy were explored. The three-equation model of Walters and Leylek was thought to be in a relatively mature state of development and was implemented in the Glenn-HT code. Two-dimensional heat transfer predictions of flat plate flow and two-dimensional and three-dimensional heat transfer predictions on a turbine blade were performed and reported herein. Surface heat transfer rate serves as sensitive indicator of transition. With the newly implemented model, it was shown that the simulation of transition process is much improved over the baseline k- model for the single Reynolds number and pressure ratio attempted; while agreement with heat transfer data became more satisfactory. Armed with the new transition model, total-pressure losses of computed three-dimensional flow of E3 tip section cascade were compared to the experimental data for a range of incidence angles. The results obtained, form a partial loss bucket for the chosen blade. In time the loss bucket will be populated with losses at additional incidences. Results obtained thus far will be discussed herein

    Variability-Aware Simulations of 5 nm Vertically Stacked Lateral Si Nanowires Transistors

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    In this work, we present a simulation study of vertically stacked lateral nanowires transistors (NWTs) considering various sources of statistical variability. Our simulation approach is based on various simulations techniques to capture the complexity in such ultra-scaled device

    Comparison of efficacy Ephedrine and phenylephrine in Postoperative Vomiting in Cesarean section

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    Introduce: Postoperative nausea and vomiting (PONV) still is the most big problem event encountered in the PACU (Post Anesthesia Care Unit), despite advances in prevention and treatment. The incidence of PONV has remained high and has a major negative impact on patient satisfaction about the overall surgical experience. Method: In double-blind, clinical trial, 104 patients were undergoing cesarean section was randomizing into two groups: Group P (100μg Phenylephrine) and Group E (6μg Ephedrine). We compared the Vomiting parameters between the two groups. Result: Patients in the recovery were compared in 2 groups regarding occurrence of vomiting that no statistical difference between two group (P >0.05). The results show that vomiting was seen in ASA1, and in ASA2 no vomiting was observed. The incidence of vomiting was 2 patients in young group and 1 patient in middle-aged group. The incidence of vomiting was 2 patients in slim group, 1 in moderate group and no sign of vomiting has been seen in the obese group. Conclusion: We conclude that ephedrine is the best drug for antiemetic prophylaxis before cesarean surgery based on cost and lack of side effects

    Position-Dependent Performance in 5 nm Vertically Stacked Lateral Si Nanowires Transistors

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    In this work, we investigated the performance of vertically stacked lateral nanowires transistors (NWTs) considering the effects of series resistance. Also, we consider the vertical positions of the lateral nanowires in the stack and diameter variation of the lateral NWTs as new sources of process variability

    United States-Mexico Income Tax Treaty: Relief from Double Taxation, The

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    United States-Mexico Income Tax Treaty: Relief from Double Taxation, The

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