Quantum noise imposes a fundamental limitation on the sensitivity of interferometric gravitational-wave detectors like LIGO, manifesting as shot noise and quantum radiation pressure noise. Here, we ...present the first realization of frequency-dependent squeezing in full-scale gravitational-wave detectors, resulting in the reduction of both shot noise and quantum radiation pressure noise, with broadband detector enhancement from tens of hertz to several kilohertz. In the LIGO Hanford detector, squeezing reduced the detector noise amplitude by a factor of 1.6 (4.0 dB) near 1 kHz; in the Livingston detector, the noise reduction was a factor of 1.9 (5.8 dB). These improvements directly impact LIGO’s scientific output for high-frequency sources (e.g., binary neutron star postmerger physics). The improved low-frequency sensitivity, which boosted the detector range by 15%–18% with respect to no squeezing, corresponds to an increase in the astrophysical detection rate of up to 65%. Frequency-dependent squeezing was enabled by the addition of a 300-meter-long filter cavity to each detector as part of the LIGO A+ upgrade.
The two interferometers of the Laser Interferometry Gravitaional-wave Observatory (LIGO) recently detected gravitational waves from the mergers of binary black hole systems. Accurate calibration of ...the output of these detectors was crucial for the observation of these events, and the extraction of parameters of the sources. The principal tools used to calibrate the responses of the second-generation (Advanced) LIGO detectors to gravitational waves are systems based on radiation pressure and referred to as Photon Calibrators. These systems, which were completely redesigned for Advanced LIGO, include several significant upgrades that enable them to meet the calibration requirements of second-generation gravitational wave detectors in the new era of gravitational-wave astronomy. We report on the design, implementation, and operation of these Advanced LIGO Photon Calibrators that are currently providing fiducial displacements on the order of \(10^{-18}\) m/\(\sqrt{\textrm{Hz}}\) with accuracy and precision of better than 1 %.
One of the salient features of the recent populist turn in Europe has been a redefinition of the European. Traditionally, (far) right-wing parties defined themselves as Eurosceptic and focused on ...national identity. Increasingly, however, they have referred to pan-European heritage, although against the mainstream conceptualization of it. The article looks at the case of Hungary and the image of Europe constructed by the Hungarian Prime Minister Viktor Orbán, whose rhetoric has become a key reference point for other European populist movements. The past decade his government has witnessed, on the one hand, a tendency to redefine what is European against the dominant and institutionalized interpretations, and, on the other, an attempt to single-out the concept of Central Europe as the locus for maintaining and nurturing European values in contrast to perceived Western decline. This paper examines this discourse through a close reading of major speeches delivered by Orbán on the anniversaries of historical events. Analysis of these speeches reveals the ideological foundations of his political project and presents historical and philosophical interpretations of the European political situation. It seeks to identify how Orbán’s discourse evolved across time, by putting the speeches about the past into the present political context.
W artykule podjęto próbę odpowiedzi na pytanie, jak w przedsiębiorstwach z sektora MŚP podczas pandemii COVID-19 funkcjonował model pracy zdalnej. W anonimowej ankiecie badani ...(właściciele/zarządzający firmą MŚP) odpowiadali na pytania dotyczące pracy zdalnej przed pandemią, zakresu zadań wykonywanych zdalnie w czasie pandemii, trudności i ograniczeń tego modelu pracy oraz stopnia zadowolenia z wykonywania zadań zawodowych poza miejscem zatrudnienia. Badani byli też pytani o to, czy po zakończeniu pandemii chcieliby nadal pracować zdalnie. W czasie pandemii przedsiębiorcy MŚP korzystali z modelu pracy zdalnej, ale ta forma pracy nie przysparzała im szczególnych trudności, a pod względem zadań związanych z przygotowywaniem dokumentów okazała się bardziej efektywna niż model stacjonarny. Praca zdalna miała tyleż zwolenników, co przeciwników. To, co dla jednych było największym ograniczeniem – łączenie obowiązków domowych z zawodowymi – dla innych stawało się zaletą. Kobietom to zadanie przychodziło łatwiej niż mężczyznom, o czym świadczy fakt, że więcej kobiet niż mężczyzn chciałoby pracować zdalnie po zakończeniu pandemii. Pandemia spowodowała wzrost popularności wideokonferencji, które stały się niemal tak samo powszechne, jak korzystanie z maili czy telefonów w sprawach biznesowych.
W artykule podjęto próbę odpowiedzi na pytanie, jak pandemia COVID-19 wpłynęła na podróże służbowe w polskich przedsiębiorstwach z sektora MSP. W anonimowej ankiecie badani (właściciele/zarządzający ...firmą MSP) odpowiadali na pytania dotyczące częstotliwości podróży służbowych, długości podróży i pokonywanych dystansów, głównych celów oraz środków transportu w latach przed pandemią i w czasie pandemii. Wyniki wskazują na to, że w czasie pandemii zmniejszyła się wprawdzie częstość wyjazdów służbowych, ale nie tak znacząco, jak pokazują inne badania, prowadzone np. wśród pracowników korporacji. Wyraźnie skróciła się natomiast długość podróży oraz preferowano bliższe destynacje, korzystając z własnych środków transportu (samochód). Podróże służbowe odbywano przede wszystkim w celu spotkania się z partnerem biznesowym oraz realizacji zobowiązań, natomiast spadło zainteresowanie udziałem w wyjazdowych kursach i szkoleniach. Na podstawie wyników ankiety stwierdzono, że właściciele i menedżerowie małych i średnich przedsiębiorstw nawet w czasie pandemii starali się realizować swoje główne cele biznesowe podczas podróży służbowych, biorąc odpowiedzialność za los przedsiębiorstwa i podejmując wysiłki, by mimo ograniczeń i kryzysu wywołanego pandemią przetrwać na trudnym rynku.
The article attempts to answer the question of how the remote work model functioned in enterprises from the SME sector during the COVID-19 coronavirus pandemic. In an anonymous survey, the ...respondents (owners/managers of an SME company) answered questions about remote work before the pandemic, the scope of tasks performed remotely during a pandemic, the difficulties and limitations of this work model and the degree of satisfaction with performing professional tasks outside the place of employment. The respondents were also asked if they would like to continue working remotely after the end of the pandemic. During the pandemic, SME entrepreneurs used the remote working model, but this form of work did not pose any particular difficulties to them, and when it comes to tasks related to the preparation of documents, it turned out to be more effective than the stationary model. Remote work had as many supporters as opponents. What was the greatest limitation for some - combining home and work duties - became an advantage for others. Women found this task easier than men, as evidenced by the fact that more women than men would like to work remotely after the pandemic ends. The pandemic has increased the popularity of videoconferencing, which has become almost as common as the use of e-mail or phone calls for business matters.
It is shown that a simple active oscillating circuit with memristor yields quite complicated two-parameter bifurcation diagrams. When two (out of three) parameters of the circuit change ...simultaneously, various periodic, chaotic and unstable solutions are obtained. Those solutions result from parallel computing, as a single two-parameter bifurcation diagram requires solving the underlying model hundred of thousands (or even a few million) times. Such diagrams when complemented with one-parameter ones show surprisingly complex bifurcation patterns for the simple circuit having a very weak nonlinearity present in only one of the three differential equations. Color two-parameter bifurcation diagrams are included in this brief.
Many vaccine rationing guidelines urge planners to recognize, and ideally reduce, inequities. In the United States, allocation frameworks are determined by each of the Centers for Disease Control and ...Prevention's 64 jurisdictions (50 states, the District of Columbia, five cities and eight territories). In this study, we analyzed vaccine allocation plans published by 8 November 2020, tracking updates through to 30 March 2021. We evaluated whether jurisdictions adopted proposals to reduce inequity using disadvantage indices and related place-based measures. By 30 March 2021, 14 jurisdictions had prioritized specific zip codes in combination with metrics such as COVID-19 incidence, and 37 jurisdictions (including 34 states) had adopted disadvantage indices, compared to 19 jurisdictions in November 2020. Uptake of indices doubled from 7 to 14 among the jurisdictions with the largest shares of disadvantaged communities. Five applications were distinguished: (1) prioritizing disadvantaged groups through increased shares of vaccines or vaccination appointments; (2) defining priority groups or areas; (3) tailoring outreach and communication; (4) planning the location of dispensing sites; and (5) monitoring receipt. To ensure that equity features centrally in allocation plans, policymakers at the federal, state and local levels should universalize the uptake of disadvantage indices and related place-based measures.
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