507 research outputs found

    Provably Safe Reinforcement Learning via Action Projection using Reachability Analysis and Polynomial Zonotopes

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    While reinforcement learning produces very promising results for many applications, its main disadvantage is the lack of safety guarantees, which prevents its use in safety-critical systems. In this work, we address this issue by a safety shield for nonlinear continuous systems that solve reach-avoid tasks. Our safety shield prevents applying potentially unsafe actions from a reinforcement learning agent by projecting the proposed action to the closest safe action. This approach is called action projection and is implemented via mixed-integer optimization. The safety constraints for action projection are obtained by applying parameterized reachability analysis using polynomial zonotopes, which enables to accurately capture the nonlinear effects of the actions on the system. In contrast to other state-of-the-art approaches for action projection, our safety shield can efficiently handle input constraints and dynamic obstacles, eases incorporation of the spatial robot dimensions into the safety constraints, guarantees robust safety despite process noise and measurement errors, and is well suited for high-dimensional systems, as we demonstrate on several challenging benchmark systems

    Q-switched laser damage of infrared nonlinear materials

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    Q-switched laser-damage thresholds have been determined for six materials (proustite – Ag3AsS3, pyrargyrite – Ag3SbS3, cinnabar – HgS, silver thiogallate – AgGaS2, tellurium – Te, and gallium arsenide – GaAs) of interest for nonlinear optics in the medium infrared. Four TEM00 mode lasers were employed with outputs at wavelengths of 694 nm, 1.06, 2.098, and 10.6 Β΅m. Damage has been found to be confined to the surface of the crystals and occurs for radiation intensities between 3 and 75 MW/cm2. Particular care is needed in the cutting and polishing of tellurium crystals if a high-damage threshold is to be achieved

    ΠžΠΏΡ‚ΠΈΠΌΠΈΠ·Π°Ρ†ΠΈΡ вычислСния ΠΎΠ±Ρ€Π°Ρ‚Π½ΠΎΠ³ΠΎ Π‘ΠŸΠ€ Π½Π° многоядСрном процСссорС

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    The article describes the method of calculating the inverse FFT N-point sequence with a N-point complex FFT, also the implementation of similar approach for computing on multi-core computing architecture. The main quality parameters of similar organization such as speedup and efficiency of computing resources were analyzed

    Sensitive HPV detection in oropharyngeal cancers.

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    BACKGROUND: Human papillomaviruses (HPV) are the aetiological agents of certain benign and malignant tumours of skin and mucosae; the most important of which is cervical cancer. Also, the incidence of ano-genital warts, HPV-anal cancer and oropharyngeal cancers are rising. To help ascertain a useful PCR detection protocol for oropharyngeal cancers, we directly compared three commonly used primer sets in detection of HPV from different clinical samples. METHODS: We compared PGMY09/11, MY09/11 and GP5+/6+ primers sets in PCRs of 34 clinically diagnosed samples of genital warts, cervical brushings (with associated histological diagnosis) and vulval biopsies. All negative samples were subsequently tested using the previously reported PGMY/GP PCR method and amplicons directly sequenced for confirmation and typing. An optimised PCR protocol was then compared to a line blot assay for detection of HPV in 15 oropharyngeal cancer samples. RESULTS: PGMY09/11 primers detected HPV presence in more cervical brushing (100%) and genital wart (92.9%) samples compared to MY09/11 (90% and 64.3%) and GP5+/6+ (80% and 64.3%) primer sets, respectively. From vulval biopsies, HPV detection rates were: MY09/11 (63.6%), GP5+/6+ (54.5%) and PGMY09/11 (54.5%). PGMY/GP nested PCR demonstrated that HPV was present, and direct sequencing confirmed genotypes. This nested PCR protocol showed detection of HPV in 10/15 (66.7%) of oropharyngeal cancer samples. CONCLUSIONS: PGMY09/11 primers are the preferred primer set among these three for primary PCR screening with different clinical samples. MY09/11 and GP5+/6+ may be used (particularly for cervical samples) but demonstrate lower detection rates. A nested PCR approach (i.e. a PGMY-GP system) may be required to confirm negativity or to detect low levels of HPV, undetectable using current primary PCR methods, as demonstrated using oropharyngeal cancer samples.RIGHTS : This article is licensed under the BioMed Central licence at http://www.biomedcentral.com/about/license which is similar to the 'Creative Commons Attribution Licence'. In brief you may : copy, distribute, and display the work; make derivative works; or make commercial use of the work - under the following conditions: the original author must be given credit; for any reuse or distribution, it must be made clear to others what the license terms of this work are

    Portfolio Vol. II N 3

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    Jeffers, Robinson. From \u27The Beaks of Eagles\u27 . Poem. 6. Clement, Harry. Mr. Bigger Tries Faith . Prose. 7. Shaw, A.A. Students of Denison . Prose. 9 Deweerd, H.A. New German War Prophets . Prose. 11. West, Bill C. Reproach . Poem. 14. West, Bill C. Dilemma . Poem. 14. Manship, Paul. Dancer and Gazelles . Picture. 14. Saunders, Paul. Review of New Books . Prose. 15. Smith, Bob. Review of New Records . Prose. 15. Picasso, Pablo. Nude (Pink) . Picture. 16. Korbel, Mario. The Andante . Picture. 16. Bethune, Don. Review of \u27Susan and God\u27 . Prose. 17. Baily, Bernard. Thornton Wilder\u27s \u27Out Town Reviewed . 17. Maxwell, Robert. Reflections . Poem. 18. Carter, Clarence Holbrook. July . Picture. 18. Browne, Phil. The Drag . Picture. 2. Browne, Phil. A Faithful Servant . Prose. 19. Hanna, Stanley. Jazz . Poem. 20. Hanna, Stanley. M.A. . Poem. 20. Whistler, James McNeill. Rotherhithe . Wager, Dick. Black . Poem. 22. Wager, Dick. Ruthless . Poem. 22. Wager, Dick. Train . Poem. 22. Martindale, Virginia. Song of a Cynic . Poem. 22. Blazys, Alexander. Russian Dancers . Picture. 22. Price II, Ira. The Rains Fell . Prose. 5

    Условия формирования ΠΈ ΠΏΡ€ΠΎΠ±Π»Π΅ΠΌΡ‹ функционирования ΠΊΡ€ΡƒΠΏΠ½Ρ‹Ρ… дивСрсифицированных производствСнно-ΠΊΠΎΡ€ΠΏΠΎΡ€Π°Ρ‚ΠΈΠ²Π½Ρ‹Ρ… структур Π² Π£ΠΊΡ€Π°ΠΈΠ½Π΅

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    Π£ статті розглянуто ΡƒΠΌΠΎΠ²ΠΈ формування Ρ‚Π° функціонування, Π° Ρ‚Π°ΠΊΠΎΠΆ історія Ρ€ΠΎΠ·Π²ΠΈΡ‚ΠΊΡƒ Π²Π΅Π»ΠΈΠΊΠΈΡ… дивСрсифікованих Π²ΠΈΡ€ΠΎΠ±Π½ΠΈΡ‡ΠΎ-ΠΊΠΎΡ€ΠΏΠΎΡ€Π°Ρ‚ΠΈΠ²Π½ΠΈΡ… структур Π² Π£ΠΊΡ€Π°Ρ—Π½Ρ–. ΠŸΡ€ΠΎΠΏΠΎΠ½ΡƒΡŽΡ‚ΡŒΡΡ ΠΏΡ–Π΄Ρ…ΠΎΠ΄ΠΈ ΠΎΡ†Ρ–Π½ΠΊΠΈ Ρ€Π΅Π·ΡƒΠ»ΡŒΡ‚Π°Ρ‚ΠΈΠ²Π½ΠΎΡΡ‚Ρ– процСсу дивСрсифікації Π· використанням Ρ€Ρ–Π·Π½ΠΈΡ… ΠΌΠ΅Ρ‚ΠΎΠ΄ΠΈΠΊ. Π’ΠΈΠ·Π½Π°Ρ‡Π΅Π½ΠΎ, Ρ‰ΠΎ Π² Π΄Π°Π½ΠΈΠΉ час ΠΎΡ†Ρ–Π½ΠΊΠ° Ρ€Π΅Π·ΡƒΠ»ΡŒΡ‚Π°Ρ‚ΠΈΠ²Π½ΠΎΡΡ‚Ρ– процСсу дивСрсифікації ΠΌΠΎΠΆΠ»ΠΈΠ²Π° лишС нСпрямими ΠΌΠ°Ρ‚Π΅ΠΌΠ°Ρ‚ΠΈΡ‡Π½ΠΈΠΌΠΈ ΠΌΠ΅Ρ‚ΠΎΠ΄Π°ΠΌΠΈ.Π’ ΡΡ‚Π°Ρ‚ΡŒΠ΅ рассмотрСны условия формирования ΠΈ функционирования, Π° Ρ‚Π°ΠΊΠΆΠ΅ история развития ΠΊΡ€ΡƒΠΏΠ½Ρ‹Ρ… дивСрсифицированных производствСнно-ΠΊΠΎΡ€ΠΏΠΎΡ€Π°Ρ‚ΠΈΠ²Π½Ρ‹Ρ… структур Π² Π£ΠΊΡ€Π°ΠΈΠ½Π΅. ΠŸΡ€Π΅Π΄Π»Π°Π³Π°ΡŽΡ‚ΡΡ ΠΏΠΎΠ΄Ρ…ΠΎΠ΄Ρ‹ ΠΎΡ†Π΅Π½ΠΊΠΈ Ρ€Π΅Π·ΡƒΠ»ΡŒΡ‚Π°Ρ‚ΠΈΠ²Π½ΠΎΡΡ‚ΠΈ процСсса дивСрсификации с использованиСм Ρ€Π°Π·Π½Ρ‹Ρ… ΠΌΠ΅Ρ‚ΠΎΠ΄ΠΈΠΊ. ΠžΠΏΡ€Π΅Π΄Π΅Π»Π΅Π½ΠΎ, Ρ‡Ρ‚ΠΎ Π² настоящСС врСмя ΠΎΡ†Π΅Π½ΠΊΠ° Ρ€Π΅Π·ΡƒΠ»ΡŒΡ‚Π°Ρ‚ΠΈΠ²Π½ΠΎΡΡ‚ΠΈ процСсса дивСрсификации Π²ΠΎΠ·ΠΌΠΎΠΆΠ½Π° лишь косвСнными матСматичСскими ΠΌΠ΅Ρ‚ΠΎΠ΄Π°ΠΌΠΈ.In the article address the formation and functioning of the conditions, as well as story development of large industrial and corporate structures, becoming diversification in Ukraine. Proposes approaches assessing impact of the process of diversification, using of different methods. Proved that the current performance assessment process of diversification can only be indirect mathematical methods

    'Silence bleeds': Hamlet across borders : The Shakespearean Adaptations of Sulayman Al-Bassam

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    Original article can be found at: http://www.informaworld.com/smpp/title~content=t713734315~db=all Copyright Informa / Taylor and FrancisThis article addresses the writing and performance work of Anglo-Kuwaiti director Sulayman Al-Bassam, tracing the development of his various adaptations of Shakespeare's Hamlet into English and Arabic 'cross-cultural' versions between 2001 and 2007. Al-Bassam's work presents English as a 'language in translation'. His works move from early modern to modern English, from Arabized English to Arabic, from one linguistic and geographical location to another, their forms moulded and remoulded by complex cultural pressures. The study focuses on specific examples from three adaptations to show in practice how in these works English is 'constantly crossed, challenged and contested'Peer reviewedFinal Accepted Versio

    Landau level mixing and spin degeneracy in the quantum Hall effect

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    We study dynamics of electrons in a magnetic field using a network model with two channels per link with random mixing in a random intrachannel potential; the channels represent either two Landau levels or two spin states. We consider channel mixing as function of the energy separation of the two extended states and show that its effect changes from repulsion to attraction as the energy separation increases. For two Landau levels this leads to level floating at low magnetic fields while for Zeeman split spin states we predict level attraction at high magnetic fields, accounting for ESR data. We also study random mixing of two degenerate channels, while the intrachannel potential is periodic (non-random). We find a single extended state with a localization exponent Ξ½β‰ˆ1.1\nu\approx 1.1 for real scattering at nodes; the general case has also a single extended state, though the localized nature of nearby states sets in at unusually large scales.Comment: 18 pages, 11 tex-files and 1 ps-file of figure

    Portfolio Vol. I N 3

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    Sweitzer, Harry J. Portfolio Goes to Press . Prose. 1. Browne, Phil. William Howard Doane Library . Picture. 2. Overhuls, James. Out of Himself . Prose. 3. MacNeill, Annie Marie. To President and Mrs. Shaw . Poem. 6. Baker, George. Saint in a Silo . Prose 7. Beckham, Adela. In Moods . Poem. 8. Vincent, Charles. Incident of August 7, 1930. Prose. 9. Flory, Doris. Opinions . Poem. 10. Flory, Doris. Thoughts in Spring . Poem. 10. Flory, Doris. Breakfast Scene . Poem. 10. Shaw, Robert B. A Date for the Dances . Prose. 11. Cronberger, Barbara. And the Years Go On . Prose. 13. Hanna, Stanley. Reola, Reola . Poem. 14. Hanna, Stanley. The Dance of the Kobolds . Poem. 14. Nadel, Norman. I died Last Night . Prose. 15. Bethune, Don S. Adolescence . Poem 16. Vodev, Eugene. The Black Day of Bulgaria . Prose. 17. Dick, Pewilla. To a White Violet . Poem. 18. Dick, Pewilla. As With Your Shadow . Poem. 18. Dwelly, Thorndike. Of Mice and Men . Prose. 19. Clements, Helen. Our Town . Prose. 19. Schlle, Alice. Marion is an Old Costume . Picture. 20. Chadeayne, Robert. Factory . Picture. 20. Nadel, Norman. Dmitri Shostakovitch . Prose. 21. Stewart, John. Duke Ellington\u27s Records . Prose. 21. Beck, Virginia. The Dance as an Art . Prose. 22. Dick, Pewilla. Death . Poem. 23. Flory, Doris. On Reforms . Poem. 24. Beckham, Adela. The Lie . Poem. 24. Bethune, Don. Futility . Poem. 24
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