1,880 research outputs found
DeeLeMa: Missing information search with Deep Learning for Mass estimation
We present DeeLeMa, a deep learning network to analyze energies and momenta
in particle collisions at high energy colliders, especially DeeLeMa is
constructed based on symmetric event topology, and the generated mass
distributions show robust peaks at the physical masses after the combinatoric
uncertainties, and detector smearing effects are taken into account. DeeLeMa
can be widely used in different event topologies by adopting the corresponding
kinematic symmetries
Erosion of Public Confidence in the Korean National Assembly
Using recent survey data, this paper aims to empirically investigate the state and source of Korean citizens' trust and confidence in the National Assembly. Roughly speaking, the National Assembly is trusted only by one out of ten citizens. Since the country's democratization, citizens' trust and confidence has been eroding. Presently, the National Assembly is the least trusted among the key public or private institutions. A cross-national comparison of liberal democracies in the world shows that only a few national legislatures are less trusted by their citizens than the Korean National Assembly. Furthermore, this study confirms the empirical validity of performance-based explanation about what factors generate citizens' trust and confidence in the National Assembly. At the aggregate level, an erosion of citizens' trustful attitude toward the legislature is matched by their decreased positive evaluation of the overall job performance by the legislature. At the individual level, a citizen's legislative trust and confidence depends mainly on his or her evaluation of the performance of the legislature itself, the executive interacting with it, or the democratic regime as a whole. Most Koreans pass an unfavorable judgment on the performance of the legislature, not because they think it is a simply idle institution but because politicians are seen to pursue partisan interests too frantically within the institution. Given its drained reservoir of citizens' favorable attitudes toward it, the present National Assembly, even with its heightened constitutional status and emerging policy activism, may not be likely to serve as a key agent for facilitating democratic consolidation on Korean soil
Timing information at HL-LHC: complete determination of masses of dark matter and long lived particle
A long-standing kinematic challenge in data analysis at hadron colliders is the determination of the masses of invisible particles. This issue is particularly relevant in searches for evidence of dark matter production, which remains one of the prominent targets of future collider experiments. In this paper, we show that the additional information from the precision timing measurements, provided by planned detector upgrades during the high- luminosity run of the LHC (HL-LHC), allows for previously unrealizable measurements of invisible particle kinematics. As a concrete example, we focus on the signal of pair produced long-lived particles (LLP1,2), each decaying with a displaced vertex to visible (V1,2) and invisible (I1,2) final state particles, pp â LLP1 + LLP2 â (V1 + I1) + (V2 + I2). We explicitly show that the complete kinematics of the invisible particles in such events can be determined with the addition of timing information, and evaluate the precision with which the masses of new long-lived and invisible particles can be determined
Enhanced magnetic and thermoelectric properties in epitaxial polycrystalline SrRuO3 thin film
Transition metal oxide thin films show versatile electrical, magnetic, and
thermal properties which can be tailored by deliberately introducing
macroscopic grain boundaries via polycrystalline solids. In this study, we
focus on the modification of the magnetic and thermal transport properties by
fabricating single- and polycrystalline epitaxial SrRuO3 thin films using
pulsed laser epitaxy. Using epitaxial stabilization technique with atomically
flat polycrystalline SrTiO3 substrate, epitaxial polycrystalline SrRuO3 thin
film with crystalline quality of each grain comparable to that of
single-crystalline counterpart is realized. In particular, alleviated
compressive strain near the grain boundaries due to coalescence is evidenced
structurally, which induced enhancement of ferromagnetic ordering of the
polycrystalline epitaxial thin film. The structural variations associated with
the grain boundaries further reduce the thermal conductivity without
deteriorating the electronic transport, and lead to enhanced thermoelectric
efficiency in the epitaxial polycrystalline thin films, compared with their
single-crystalline counterpart.Comment: 24 pages, 5 figure
Analog Self-Interference Cancellation With Practical RF Components for Full-Duplex Radios
One of the main obstacles in full-duplex radios is analog-to-digital converter (ADC) saturation on a receiver due to the strong self-interference (SI). To solve this issue, researchers have proposed two different types of analog self-interference cancellation (SIC) methodsâi) passive suppression and ii) regeneration-and-subtraction of SI. For the latter case, the tunable RF component, such as a multi-tap circuit, reproduces and subtracts the SI. The resolutions of such RF components constitute the key factor of the analog SIC. Indeed, they are directly related to how well the SI is imitated. Another major issue in analog SIC is the inaccurate estimation of the SI channel due to the nonlinear distortions, which mainly come from the power amplifier (PA). In this paper, we derive a closed-form expression for the SIC performance of the multi-tap circuit; we consider how the RF components must overcome such practical impairments as digitally-controlled attenuators, phase shifters, and PA. For a realistic performance analysis, we exploit the measured PA characteristics and carry out a 3D ray-tracing-based, system-level throughput analysis. Our results confirm that the non-idealities of the RF components significantly affect the analog SIC performance. We believe our study provides insight into the design of the practical full-duplex system
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