1,004 research outputs found

    Automated Software Transplantation

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    Automated program repair has excited researchers for more than a decade, yet it has yet to find full scale deployment in industry. We report our experience with SAPFIX: the first deployment of automated end-to-end fault fixing, from test case design through to deployed repairs in production code. We have used SAPFIX at Facebook to repair 6 production systems, each consisting of tens of millions of lines of code, and which are collectively used by hundreds of millions of people worldwide. In its first three months of operation, SAPFIX produced 55 repair candidates for 57 crashes reported to SAPFIX, of which 27 have been deem as correct by developers and 14 have been landed into production automatically by SAPFIX. SAPFIX has thus demonstrated the potential of the search-based repair research agenda by deploying, to hundreds of millions of users worldwide, software systems that have been automatically tested and repaired. Automated software transplantation (autotransplantation) is a form of automated software engineering, where we use search based software engineering to be able to automatically move a functionality of interest from a ‘donor‘ program that implements it into a ‘host‘ program that lacks it. Autotransplantation is a kind of automated program repair where we repair the ‘host‘ program by augmenting it with the missing functionality. Automated software transplantation would open many exciting avenues for software development: suppose we could autotransplant code from one system into another, entirely unrelated, system, potentially written in a different programming language. Being able to do so might greatly enhance the software engineering practice, while reducing the costs. Automated software transplantation manifests in two different flavors: monolingual, when the languages of the host and donor programs is the same, or multilingual when the languages differ. This thesis introduces a theory of automated software transplantation, and two algorithms implemented in two tools that achieve this: µSCALPEL for monolingual software transplantation and τSCALPEL for multilingual software transplantation. Leveraging lightweight annotation, program analysis identifies an organ (interesting behavior to transplant); testing validates that the organ exhibits the desired behavior during its extraction and after its implantation into a host. We report encouraging results: in 14 of 17 monolingual transplantation experiments involving 6 donors and 4 hosts, popular real-world systems, we successfully autotransplanted 6 new functionalities; and in 10 out of 10 multlingual transplantation experiments involving 10 donors and 10 hosts, popular real-world systems written in 4 different programming languages, we successfully autotransplanted 10 new functionalities. That is, we have passed all the test suites that validates the new functionalities behaviour and the fact that the initial program behaviour is preserved. Additionally, we have manually checked the behaviour exercised by the organ. Autotransplantation is also very useful: in just 26 hours computation time we successfully autotransplanted the H.264 video encoding functionality from the x264 system to the VLC media player, a task that is currently done manually by the developers of VLC, since 12 years ago. We autotransplanted call graph generation and indentation for C programs into Kate, (a popular KDE based test editor used as an IDE by a lot of C developers) two features currently missing from Kate, but requested by the users of Kate. Autotransplantation is also efficient: the total runtime across 15 monolingual transplants is 5 hours and a half; the total runtime across 10 multilingual transplants is 33 hours

    Automated transplantation of call graph and layout features into Kate

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    We report the automated transplantation of two features currently missing from Kate: call graph generation and automatic layout for C programs, which have been requested by users on the Kate development forum. Our approach uses a lightweight annotation system with Search Based techniques augmented by static analysis for automated transplantation. The results are promising: on average, our tool requires 101 min of standard desktop machine time to transplant the call graph feature, and 31 min to transplant the layout feature. We repeated each experiment 20 times and validated the resulting transplants using unit, regression and acceptance test suites. In 34 of 40 experiments conducted our search-based autotransplantation tool, μSCALPEL, was able to successfully transplant the new functionality, passing all tests

    Revascularization of the myocardium with the use of both internal thoracic arteries in the multivascular diseases of the coronary arteries

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    Secția Chirurgie Cardiacă a Viciilor Dobândite, IMSP Spitalul Clinic Republican ”Timofei Moșneaga”, Chișinau, Republica Moldova, Al XIII-lea Congres al Asociației Chirurgilor „Nicolae Anestiadi” și al III-lea Congres al Societății de Endoscopie, Chirurgie miniminvazivă și Ultrasonografie ”V.M.Guțu” din Republica MoldovaIntroducere: Artera toracica internă are cea mai buna permeabilitate din grefele folosite pentru bypass coronarian, cu permeabilitate 95-98% la 10 ani dupa intervenție. Folosirea a două aa. toracice interne asigura un rezultat bun și de durată a operațiilor de revascularizare a miocardului. Dar ponderea operațiilor cu utilizarea a două aa. toracice interne in toată lumea nu depașește 10% din toate operațiile de bypass coronarian. Material și metode: Din a.2013 pînă la 30 martie 2019 în clinica au fost efectuate 762 cazuri de bypass coronarian în afecțiunile coronariene, în 110 (14,4%) cazuri au fost folosite ambele aa. toracice interne, 104 (95%) bărbați și 6 (5%) femei, vârsta de 54±7,8 ani. Majoritatea aveau angină pectorală cl.f. III-IV, 58 (53%) infarct miocardic în anamneză. Stenoză critică de trunchi a.coronară stângă 24 (22%). Rezultate: Arterele toracice au fost montate ca T-Graft 81 (73,6%) cazuri și ˶in situ˵ 29 (26,4%). Indicele de revascularizare 3,14. Revascularizare arterială efectuată în 39 (35,4%) de cazuri. În 71 (64,5%) de cazuri a fost folosită autovena, 7 (6,4%) cazuri a.radială. A.toracică internă montată secvențial în 19 (17,3%) cazuri. 16 (14,5%) pacienți operați pe cord bătând. În 4 cazuri efectuată endarterectomie din a.carotidă internă. Letalitate 0 cazuri, infarct miocardic perioperator 1 caz, hemoragie postoperatorie 2 (1,8%), mediastenită 2 (1,8%). Concluzii: Bypass coronarian cu folosirea ambelor aa.toracice interne este o metodă contemporană și sigură în revascularizarea miocardului în afecțiunile arterelor coronare, nu mărește riscul complicațiilor perioperatorii. În prezent aceata trebuie considerată operație de alegere la majoritatea pacienților cu cardiopatie ischemică cu afectarea multivasculară aa. coronare.Background: Internal thoracic arteries have the best permeability of the grafts used for coronary bypass grafting, with 95-98% permeability 10 years after surgery. Using bilateral internal thoracic arteries has been shown to significantly improve clinical outcomes and increase long-term survival. But the proportion of operations with the use of two internal thoracic arteries worldwide does not exceed 10% of all coronary bypass surgery. Methods and materials: From 2013 to 30 March 2019 in the our clinic 762 cases of coronary artery bypass grafting in coronary diseases were performed in 110 (14.4%) cases were used bilateral internal thoracic arteries, 104 (95%) men and 6 (5%) women, 54 ± 7.8 years of age. Most had angina pectoral cl. III-IV, 58 (53%) history of myocardial infarction. Critical stenosis of left coronary artery - 24 (22%). Results: The thoracic arteries were assembled as T-Graft 81 (73.6%) cases and in situ 29 (26.4%). Revascularization Index 3.14. Blood revascularization performed in 39 (35.4%) cases. In 71 (64.5%) cases autovena was used, 7 (6.4%) cases radial artery. A. internal thoracic arteries sequentially mounted in 19 (17.3%) cases. 16 (14.5%) patients were operated off pump. In 4 cases were done endarterectomy from intern carotid artery. Lethality 0 cases, perioperative myocardial infarction 1 case, deep sternal wound infection 2 (1.8%). Conclusion: Coronary bypass with the use of bilateral internal thoracic arteries is a contemporary and safe method in the myocardial revascularization in coronary artery disease; it does not increase the risk of perioperative complications. Currently, this should be considered as a surgery for choice for the most patients with coronary artery disease

    SapFix: Automated End-To-End Repair at Scale

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    We report our experience with SapFix: the first deployment of automated end-to-end fault fixing, from test case design through to deployed repairs in production code. We have used SapFix at Facebook to repair 6 production systems, each consisting of tens of millions of lines of code, and which are collectively used by hundreds of millions of people worldwide

    Transition probabilities in the X(5) candidate 122^{122}Ba

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    To investigate the possible X(5) character of 122Ba, suggested by the ground state band energy pattern, the lifetimes of the lowest yrast states of 122Ba have been measured, via the Recoil Distance Doppler-Shift method. The relevant levels have been populated by using the 108Cd(16O,2n)122Ba and the 112Sn(13C,3n)122Ba reactions. The B(E2) values deduced in the present work are compared to the predictions of the X(5) model and to calculations performed in the framework of the IBA-1 and IBA-2 models

    g factors of coexisting isomeric states in Pb-188

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    The gg factors of the 12+{12}^{+}, {11}^{\ensuremath{-}}, and {8}^{\ensuremath{-}} isomeric states in 188Pb^{188}\mathrm{Pb} were measured using the time-differential perturbed angular distribution method as g({12}^{+})=\ensuremath{-}0.179(6), g({11}^{\ensuremath{-}})=+1.03(3), and g({8}^{\ensuremath{-}})=\ensuremath{-}0.037(7). The gg factor of the 12+{12}^{+} state follows the observed slight down-sloping evolution of the gg factors of the i13/22{i}_{13/2}^{2} neutron spherical states with decreasing NN. The gg factors of the {11}^{\ensuremath{-}} and {8}^{\ensuremath{-}} isomers proposed as oblate and prolate deformed states, respectively, were interpreted within the rotational model, using calculated and empirical gg factor values for the involved single-particle orbitals

    In-beam fast-timing measurements in 103,105,107Cd

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    Fast-timing measurements were performed recently in the region of the medium-mass 103,105,107Cd isotopes, produced in fusion evaporation reactions. Emitted gamma-rays were detected by eight HPGe and five LaBr3:Ce detectors working in coincidence. Results on new and re-evaluated half-lives are discussed within a systematic of transition rates. The 7/21+7/2_1^+ states in 103,105,107Cd are interpreted as arising from a single-particle excitation. The half-life analysis of the 11/2111/2_1^- states in 103,105,107Cd shows no change in the single-particle transition strength as a function of the neutron number
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