17 research outputs found
Measurements of b → sγ Decays at BABAR
No full textWe present measurements of the Branching Fraction and photon energy spectrum in
b → X_sγ decays in a sample of 89 million BB[overbar] pairs collected at the BABAR detector at Stanford
Linear Accelerator Center's PEP-II asymmetric B-factory. Results from a fully-inclusive and a sum
of 38 exclusive final states techniques are presented and found to be consistent with the Standard
Model calculations, as well as experimental results obtained from semileptonic b → X_clv decays
Search for B → (ρ/ω)γ decays at BABAR
No full textWe present the results of the search for the decays ß(0/±) ? ?(0/±)? (previously observed) and ß0 ? ?? (for which currently only an upper limit exists). Together with ß ? K*? decays, B ? (?/?)? allow us to measure the ratio of CKM-matrix elements |Vtd/Vts|. The analysis is based on the full BaBar dataset of 424.35 fb-1, corresponding to 465 million BB pairs, and makes heavy use of multivariate classification techniques based on decision trees. We find ßR(B ? ?±? ) = (1.20+0.42-0.38±0.20)×10-6, ßR(B ? ?0?)= (0.95+0.23-0.21 ±0.06)×10-6, and ßR(B ? ??)=(0.51+0.27-0.24±0.10)×10-6, where the first error is statistical and the second is systematic. We do not observe a statistically significant signal in the latter channel and set an upper limit at ßR(B ? ??) < 0.9 × 10-6 (90% C.L.). We also measure the isospin and SU(3)F violating quantities ?(B+ ? ?+?)/2?(B0 ? ?0?) - 1 = -0.43+0.25-0.22±0.10 and ?(B ? ??)/?(B0 ? ?0?) - 1 = -0.49+0.30-0.27±0.10.</p
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Search for B to rho/omega gamma decays at BaBar
No full textThe authors present the results of the search for the decays B{sup 0/{+-}} {yields} {rho}{sup 0/{+-}}{gamma} (previously observed) and B{sup 0} {yields} {omega}{gamma} (for which currently only an upper limit exists). Together with B {yields} K*{gamma} decays, B {yields} ({rho}/{omega}){gamma} allow us to measure the ratio of CKM-matrix elements |V{sub td}/V{sub ts}|. The analysis is based on the full BABAR dataset of 424.35 fb{sup -1} corresponding to 465 million B{bar B} pairs, and makes heavy use of multivariate classification techniques based on decision trees. They find {Beta}(B{sup {+-}} {yields} {rho}{sup {+-}}{gamma}) = (1.20{sub -0.38}{sup +0.42} {+-} 0.20) x 10{sup -6}, {Beta}(B{sup 0} {yields} {rho}{sup 0}{gamma}) = (0.95{sub -0.21}{sup +0.23} {+-} 0.06) x 10{sup -6}, {Beta}(B{sup 0} {yields} {omega}{gamma}) = (0.51{sub -0.24}{sup +0.27} {+-} 0.10) x 10{sup -6}, where the first error is statistical and the second is systematic. They do not observe a statistically significant signal in the latter channel and set an upper limit at {Beta}(B{sup 0} {yields} {omega}{gamma}) < 0.9 x 10{sup -6} (90% C.L.). They also measure the isospin and SU(3){sub F} violating quantities {Lambda}(B{sup +} {yields} {rho}{sup +}{gamma})/2{Lambda}(B{sup 0} {yields} {rho}{sup 0}{gamma})-1 = -0.43{sub -0.22}{sup +0.25} {+-} 0.10 and {Lambda}(B{sup 0} {yields} {omega}{gamma})/{Lambda}(B{sup 0} {yields} {rho}{sup 0}{gamma})-1 = -0.49{sub -0.27}{sup +0.30} {+-} 0.10
The Wireless Control Bus: Enabling Efficient Multi-Hop Event-Triggered Control with Concurrent Transmissions
No full textEvent-triggered control (ETC) holds the potential to significantly improve the efficiency of wireless networked control systems. Unfortunately, its real-world impact has hitherto been hampered by the lack of a network stack able to transfer its benefits from theory to practice specifically by supporting the latency and reliability requirements of the aperiodic communication ETC induces. This is precisely the contribution of this article.Our Wireless Control Bus (WCB) exploits carefully orchestrated network-wide floods of concurrent transmissions to minimize overhead during quiescent, steady-state periods, and ensures timely and reliable collection of sensor readings and dissemination of actuation commands when an ETC triggering condition is violated. Using a cyber-physical testbed emulating a water distribution system controlled over a real-world multi-hop wireless network, we show that ETC over WCB achieves the same quality of periodic control at a fraction of the energy costs, therefore unleashing and concretely demonstrating its full potential for the first time.Team Manuel Mazo J
Aerosol-chemistry-climate model SOCOL-AERv1.0 code
No full text<p>Aerosol-chemistry-climate model SOCOL-AERv1.0 code used to study stratospheric aerosol evolution after Pinatubo. To run the model, one needs to have installed OpenMPI, Fortran, and NETCDF. Please contact the author to get access for model initial and boundary conditions.</p>
Эволюция отношения гражданского общества к миграционному кризису ЕС (на примере Германии)
No full textРабота посвящена изучению отношения гражданского общества Германии к миграционному кризису. Объектом данной работы выступает сам миграционный кризис в Европейском союзе, и в частности, в Германии. В качестве предмета выбрано отношение гражданского общества Германии к миграционному кризису. Автор ставит своей целью выявление динамики отношения гражданского общества к миграционному кризису ЕС во всём его многообразии., для достижения чего были поставлены следующие задачи: 1.Уточнить содержание понятия гражданского общества и другие теоретические аспекты изучения объекта; 2.Определить контекст миграционного кризиса в Германии; 3.Рассмотреть историю протекания кризиса; 4.Определить отношение отдельных институтов гражданского общества Германии к миграционному кризису. Работа была написана в рамках методологии институционализма с использованием исторического, герменевтического и компаративного методов исследования.This study focuses on the relationship of civil society in Germany to migration crisis. The object of this work is itself the immigration crisis in the European Union, and in particular, in Germany. As the subject selected civil society in Germany to migration crisis. The author aims to explore the dynamics of the relationship of civil society to the migration crisis of the EU in all its diversity., to achieve what we set the following tasks: 1. To clarify the concept of civil society and other theoretical aspects of the study object; 2. To determine the context of the migration crisis in Germany; 3. Consider the story of the crisis; 4. To determine the attitude of certain civil society institutions in Germany to migration crisis. The work was written as part of the methodology of institutionalism, historical, hermeneutical and comparative methods of research
Selection of the vehicle type of transport AS Estonian Linearies Stadler Flirt on the example of electric and diesel trains
No full textTeostades arvutuslikke samme kujunes välja Stadler Flirt elektrirongide ja diiselrongide hindamise kriteerium, mis ennast kujuneb ekspluatatsioonis kulutatud euro ühik läbitud kilomeetrile. Selle järgi on selgelt näha, et Stadler Flirt diiselrong oma keskmiste ekspluatatsioonikuludega 0,93 €/km on kallim kui sama tüüpi elektrirong. Töö autor on veendunud, et see vahe hakkab ainult kasvama, kuna diiselrongi diislisõlmed ja temaga soetuvad abi sõlmed mingi hetk hakkavad hoolduskulude näitajad astmeliselt kasvatama. Sellega kaasnevad ka suured hooldustööd mis on ajaliselt pikem ja mahukam tava hooldustöödest. Kohe tekib otsene seos reservkooseisude kättesaamisega ja reisiliini täis mahus teenindamises. Arvestades sellega, et reisijate arv püsivalt suureneb, peaks suurendama reisirongi tihedust ja või koosseisude mahutavust. Selgus, et kasutades erinevaid veeremi liigi sama reisiliini teenindamisega, on ühe reisijakilomeetri maksumus elektrirongil soodsam kui diiselrongil. Aegviidu – Tapa vahelise lõiku pikendamine on majanduslikult otstarbekas, sest esmased arvutused on näidanud, et riigile on võimalik reisirongiliikluses kulud kokku hoida, pakkudes reisijatele parema reisirongi tihedust ja mugavust ning õigeaegselt ja valutud liiklusgraafiku täitmisele teostada veeremi pargile kõik võimalikud hooldus- ja remonditööd. Balansseeritud kulude jagamine annab võimaluse sama kulude hulgaga arendada reisijateveo seonduvad uuendused raudtee valdkonnas, pakkudes reisijatele kaasaegse mugavuse reisijateveol.In carrying out of the calculations have got the Stadler Flirt electric and diesel trains evaluation criteria which is the unit of euro spent per running kilometer (EUR / km). According to calculations it is clearly to see that the Stadler Flirt Diesel trains operation on average 0,93 EUR / km is more expensive than the same type of electric trains. The author is convinced that this gap will only increase, because the maintenance costs of the diesel train's agreggates and auxilary systems will begin gradually to grow up in the near future. It will bring the high level maintenance works which is longer and more extensive than the maintenance tasks today. Will occur the direct connection between availibility of reserve trains and full power operation on passenger's lines. Taken into account that passengers flow is continiously increasing, the passenger train traffic schedule and / or trains capacity should be increased as well. It is clarified that if use of different types of rolling stock on the same passenger line the operation cost per kilometer for electrical trains is cheaper than for diesel trains. The extension of the Aegviidu-Tapa electrified line section is economically feasible, as the primary calculations have shown that the state can save costs of the passenger traffic by providing to passengers the better traffic schedule and comfort and ontime to carry out all neccessary maintenance and repair works on the rolling stock fleet. The usage of Balanced Costs gives the opportunity with the same costs to develop the passengers traffic related innovations in the railway industry providing to passengers the modern comfort in passenger transport
The historical ozone trends simulated with the SOCOLv4 and their comparison with observations and reanalyses
No full textThere is evidence that the ozone layer has begun to recover owing to the ban on the production of halogenated ozone-depleting substances (hODS) accomplished by the Montreal Protocol and its amendments and adjustments (MPA). However, recent studies, while reporting an increase in tropospheric ozone from the anthropogenic NOx and CH4 and confirming the ozone recovery in the upper stratosphere from the effects of hODS, also indicate a continuing decline in the lower tropical and mid-latitudinal stratospheric ozone. While these are indications derived from observations, they are not reproduced by current global chemistry–climate models (CCMs), which show positive or near-zero trends for ozone in the lower stratosphere. This makes it difficult to robustly establish ozone evolution and has sparked debate about the ability of contemporary CCMs to simulate future ozone trends. We applied the new Earth system model (ESM) SOCOLv4 (SOlar Climate Ozone Links, version 4) to calculate long-term ozone trends between 1985–2018 and compare them with trends derived from the BAyeSian Integrated and Consolidated (BASIC) ozone composite and MERRA-2, ERA-5, and MSRv2 reanalyses. We designed the model experiment with a six-member ensemble to account for the uncertainty of the natural variability. The trend analysis is performed separately for the ozone depletion (1985–1997) and ozone recovery (1998–2018) phases of the ozone evolution. Within the 1998–2018 period, SOCOLv4 shows statistically significant positive ozone trends in the mesosphere, upper and middle stratosphere, and a steady increase in the tropospheric ozone. The SOCOLv4 results also suggest slightly negative trends in the extra-polar lower stratosphere, yet they barely agree with the BASIC ozone composite in terms of magnitude and statistical significance. However, in some realizations of the SOCOLv4 experiment, the pattern of ozone trends in the lower stratosphere resembles much of what is observed, suggesting that SOCOLv4 may be able to reproduce the observed trends in this region. Thus, the model results reveal marginally significant negative ozone changes in parts of the low-latitude lower stratosphere, which agrees in general with the negative tendencies extracted from the satellite data composite. Despite the slightly smaller significance and magnitude of the simulated ensemble mean, we confirm that modern CCMs such as SOCOLv4 are generally capable of simulating the observed ozone changes, justifying their use to project the future evolution of the ozone layer.Atmospheric Remote Sensin
