2,176 research outputs found
Income Inequality and Marriage
This study examines the extent to which changes in household formation exacerbated income inequality in the United States during the last two generations. Using a time-varying parameter model, the impact on how marriage decisions, changes in human capital, and fertility choices influence inequality are estimated. The estimation results show that marital sorting evolves over time and positively and increasingly affects the degree of income inequality and intergenerational human capital transmission induces path-dependent income distribution dynamics. This suggests that intrahousehold choices explain a substantial proportion of income distribution dynamics.
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
Timing information at HL-LHC: Complete determination of masses of Dark Matter and Long lived particle
A long standing problem in kinematics at the hadron colliders is to determine
the mass of invisible particles. This issue is particularly important for the
signals of dark matter, which becomes one of the prominent targets of future
collider experiments. In this paper, we show that the additional information
from the precise timing measurement, which will be available at the planned
high-liminosity run of the LHC (HL-LHC), will shade new light on the kinematics
study. As a concrete example, we focus on the signal of the pair produced
long-lived particles (), respectively leaving displaced vertex with
visible () and invisible () final state, . We explicitly show that this system is completely
solvable with timing information.Comment: 14 pages, 5 figure
Total Laparoscopic Hysterectomy and Laparoscopy-Assisted Vaginal Hysterectomy
This study suggests that total laparoscopic hysterectomy and laparoscopic-assisted vaginal hysterectomy are safe and feasible with laparoscopic-assisted hysterectomy preferred in patients with a mass involving the lower uterine segment or those with a large uterus
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
Performance Analysis of the Linear Induction Motor for the Deep-Underground High-Speed GTX
Abstract -In order to develop a deep-underground great train express (GTX) in South Korea, the specifications decision and development of a traction control system (including an inverter and a traction motor), which considers a variety of route conditions, must be advanced. In this study, we examined the running resistance properties of a high-speed traction system based on a variety of tunnel types and vehicle organization methods. Then, we studied the power requirements necessary for the traction motor to maintain balanced speed in the high-speed traction system. From this, we determined the design criteria for the development of a high-speed traction system for use in the deep-underground GTX. Finally, we designed a linear induction motor (LIM) for a propulsion system, and we used the finite element method (FEM) to analyze its performance as it travelled through deep-underground tunnels
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