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Online Supplemental for Han & Pollock (2019) [article]

Jung-Hoon Han, Timothy G. Pollock
2020 Figshare  
Appendices for the manuscript "As Good As It Gets: The Behavioral Consequences of Positional Inconsistency Across Status Hierarchies" by Jung-Hoon Han and Tim Pollock, to be published at the Academy of  ... 
doi:10.6084/m9.figshare.11662743 fatcat:quvtujaejfe6bpl6ba5eaktf7a

Phases of Mott-Hubbard bilayers [article]

Jung Hoon Han, Chenglong Jia
2006 arXiv   pre-print
A phase diagram of two Mott-Hubbard planes interacting with a short-range Coulomb repulsion is presented. Considering the case of equal amount of doping by holes in one layer as electrons in the other, a holon-doublon inter-layer exciton formation is shown to be a natural consequence of Coulomb attraction. Quasiparticle spectrum is gapped and incoherent below a critical doping δ_c due to the formation of excitons. A spin liquid insulator (SLI) phase is thus realized without the lattice
more » ... on. The critical value δ_c sensitively depends on the inter-layer interaction strength. In the tJ model description of each layer with the d-wave pairing, δ_c marks the crossover between SLI and d-wave superconductor. The SLI phase, despite being non-superconducting and charge-gapped, still shows electromagnetic response similar to that of a superfluid due to the exciton transport. Including antiferromagnetic order in the tJ model introduces magnetically ordered phases at low doping and pushes the spin liquid phase to a larger inter-layer interaction strength and higher doping concentrations.
arXiv:cond-mat/0605426v1 fatcat:v26uavsttfekhfcv6ojgecw5a4

Fluctuation-dissipation Type Theorem in Stochastic Linear Learning [article]

Manhyung Han, Jeonghyeok Park, Taewoong Lee, Jung Hoon Han
2021 arXiv   pre-print
The fluctuation-dissipation theorem (FDT) is a simple yet powerful consequence of the first-order differential equation governing the dynamics of systems subject simultaneously to dissipative and stochastic forces. The linear learning dynamics, in which the input vector maps to the output vector by a linear matrix whose elements are the subject of learning, has a stochastic version closely mimicking the Langevin dynamics when a full-batch gradient descent scheme is replaced by that of
more » ... gradient descent. We derive a generalized FDT for the stochastic linear learning dynamics and verify its validity among the well-known machine learning data sets such as MNIST, CIFAR-10 and EMNIST.
arXiv:2106.02220v1 fatcat:lbjdhnnwm5hrjeu5enimqzjxvu

Magnetic response of the J1-J2 spin Hamiltonian from classical Monte Carlo and Schwinger boson mean field theory [article]

Zhihua Yang, Jung Hoon Kim, Jung Hoon Han
2009 arXiv   pre-print
Magnetic susceptibilities at several potential ordering wave vectors (0,0), (\pi,0), and (\pi,\pi) are analyzed for the antiferromagnetic J1-J2 spin Hamiltonian by classical Monte Carlo and Schwinger boson mean field theories over the parameter range 0 \le 2J_2/J_1 \le 2. We find a nearly linear-T behavior of the uniform susceptibility that extends up to the temperature scale of J_1 within both calculation schemes when 2J_2/J_1 is sufficiently removed from the critical point 2J_2/J_1=1. The
more » ... ow of linear temperature dependence diminishes as the critical point is approached.
arXiv:0904.3809v1 fatcat:34ieuftyhvfbnhtxr3erb2vk6u

A BROADBAND TECHNIQUE FOR A DECOUPLING NETWORK IN A COMPACT ANTENNA ARRAY IN A MIMO SYSTEM

Jung Hoon Ko, Jung-Hoon Han, Noh-Hoon Myung
2014 Progress In Electromagnetics Research C  
Decoupling networks (DNs) have frequently been used to obtain high isolation performance between coupled antennas in multiple-input multiple-output (MIMO) systems due to their advantage of spatial efficiency, which is particularly important for mobile devices. However, conventional DNs suffer from narrowband limitations. In this paper, a broadband decoupling technique is proposed that broadens the isolation bandwidth using a parallel resonant point. A 1.95 GHz MIMO antenna system with 460 MHz
more » ... bandwidth (fractional bandwidth, FBW = 23.6%) is designed and measured using the scattering parameters. The isolation is found to be better than −15 dB, while the reflection coefficient is better than −6 dB. Furthermore, the antenna efficiency and envelope correlation coefficient (ECC) are evaluated in a reverberation chamber.
doi:10.2528/pierc14042901 fatcat:ui6a2vkavfhwtbhv6xw2yg4qkq

Slave rotor theory of antiferromagnetic Hubbard model [article]

Ki-Seok Kim, Jung Hoon Han
2006 arXiv   pre-print
The slave-rotor mean-field theory of Florens and Georges is generalized to the antiferromagnetic phase of the Hubbard model. An effective action consisting of a spin rotor and a fermion is derived and the corresponding saddle-point action is analyzed. Zero-temperature phase diagram of the antiferromagnetic Hubbard model is presented. While the magnetic phase persists for all values of the Hubbard interaction U, the single-particle spectral function exhibits a crossover into an incoherent phase
more » ... hen the magnetic moment m (and the corresponding U values) lies within a certain window m_c < m < 1-m_c, indicating a possible deviation from the Hartree-Fock theory.
arXiv:cond-mat/0605266v1 fatcat:oj3fzaslgvddlkljlr3etm74bi

Statistical recovery of the classical spin Hamiltonian [article]

Vinit Kumar Singh, Jung Hoon Han
2018 arXiv   pre-print
We propose a simple procedure by which the interaction parameters of the classical spin Hamiltonian can be determined from the knowledge of four-point correlation functions and specific heat. The proposal is demonstrated by using the correlation and specific heat data generated by Monte Carlo method on one- and two-dimensional Ising-like models, and on the two-dimensional Heisenberg model with Dzyaloshinkii-Moriya interaction. A recipe for applying our scheme to experimental images of
more » ... ion such as those made by magnetic force microscopy is outlined.
arXiv:1807.04884v1 fatcat:huckxruskzbsfmzsgrfr53fthq

Direct cellular delivery of human proteasomes to delay tau aggregation

Dong Hoon Han, Hee-Kyung Na, Won Hoon Choi, Jung Hoon Lee, Yun Kyung Kim, Cheolhee Won, Seung-Han Lee, Kwang Pyo Kim, Jeff Kuret, Dal-Hee Min, Min Jae Lee
2014 Nature Communications  
The 26S proteasome is the primary machinery that degrades ubiquitin (Ub)-conjugated proteins, including many proteotoxic proteins implicated in neurodegeneraton. It has been suggested that the elevation of proteasomal activity is tolerable to cells and may be beneficial to prevent the accumulation of protein aggregates. Here we show that purified proteasomes can be directly transported into cells through mesoporous silica nanoparticle-mediated endocytosis. Proteasomes that are loaded onto
more » ... rticles through non-covalent interactions between polyhistidine tags and nickel ions fully retain their proteolytic activity. Cells treated with exogenous proteasomes are more efficient in degrading overexpressed human tau than endogenous proteasomal substrates, resulting in decreased levels of tau aggregates. Moreover, exogenous proteasome delivery significantly promotes cell survival against proteotoxic stress caused by tau and reactive oxygen species. These data demonstrate that increasing cellular proteasome activity through the direct delivery of purified proteasomes may be an effective strategy for reducing cellular levels of proteotoxic proteins.
doi:10.1038/ncomms6633 pmid:25476420 fatcat:ayfvkgthqvg5lpkkrzctmujqki

Colon Cancer After Acute Diverticulitis Treatment

Kwang Hoon Oh, Koon Hee Han, Eun Jung Kim, Je Hoon Lee, Kyu Un Choi, Myung Sik Han, Jae Hong Ahn, Gab Jin Cheon
2013 Annals of Coloproctology  
Diverticulitis is the most common clinical complication of diverticular disease, affecting 10-25% of the patients with diverticula. The prevalences of diverticulitis and colon cancer tend to increase with age and are higher in industrialized countries. Consequently, diverticulitis and colon cancer have been reported to have similar epidemiological characteristics. However, the relationship between these diseases remains controversial, as is the performance of routine colonoscopy after an
more » ... of diverticulitis to exclude colon cancer. Recently, we experienced three cases of colon cancer after treating acute diverticulitis, based on which we suggest the importance of follow-up colonoscopy after acute diverticulitis.
doi:10.3393/ac.2013.29.4.167 pmid:24032118 pmcid:PMC3767867 fatcat:tud3jgfz7fbffiomoqx5asjlym

Classical Ring-exchange Processes on the Triangular Lattice [article]

June Seo Kim, Jung Hoon Han
2006 arXiv   pre-print
The effects of the ring-exchange Hamiltonian H_3 = J_3 sum_ (S_i * S_j) (S_i * S_k) on the triangular lattice are studied using classical Monte Carlo simulations. Each spin S_i is treated as a classical XY spin taking on Q equally spaced angles (Q-states clock model). For Q=6, a first-order transition into a stripe-ordered phase preempts the macroscopic classical degeneracy. For Q > 6, a finite window of critical phase exists, intervening between the low-temperature stripe phase and the high-temperature paramagnetic phase.
arXiv:cond-mat/0606433v1 fatcat:qut5hrz2azgjzi4ydxk4ndlfoa

Endothelial Dysfunction Is Associated With Major Adverse Cardiovascular Events in Peritoneal Dialysis Patients

Mi Jung Lee, Seung Hyeok Han, Jung Eun Lee, Hoon Young Choi, Chang-Yun Yoon, Eun Jin Kim, Jae Hyun Han, Ji Suk Han, Hyung Jung Oh, Jung Tak Park, Shin-Wook Kang, Tae-Hyun Yoo
2014 Medicine  
Endothelial dysfunction is implicated in increased cardiovascular risk in nondialyzed population. However, the prognostic impact of endothelial dysfunction on cardiovascular outcome has not been investigated in peritoneal dialysis (PD) patients. We prospectively determined endothelial function by brachial artery endothelium-dependent vasodilation (flow-mediated dilation [FMD]) in 143 nondiabetic PD patients and 32 controls. Primary outcome was a major adverse cardiac and cerebrovascular event
more » ... ACCE). Brachial FMD was significantly lower in PD patients than in controls (2.9% [1.3-4.7] vs 6.2% [5.4-8.3], P < 0.001). During a mean follow-up of 42 months, primary outcome was observed in 25 patients (17.5%). When patients were dichotomized by the median value of FMD (2.9%), incidence rates of MACCEs were significantly higher in the group with lower FMD compared with higher FMD (7.2 vs 3.0/100 person-years, P = 0.03). In multivariate Cox analysis, low FMD (≤2.9%) was a significant independent predictor of MACCEs (hazard ratio = 2.73, 95% confidence interval = 1.03-7.22, P = 0.04). Furthermore, multivariate fractional polynomial analysis showed that the risk of MACCE decreased steadily with higher FMD values. Impaired brachial FMD was a significant independent predictor of MACCEs in PD patients. Estimating endothelial dysfunction by brachial FMD could be useful for stratifying cardiovascular risk in these patients.
doi:10.1097/md.0000000000000073 pmid:25192486 pmcid:PMC4616272 fatcat:qqlgw4eprfcdtn2ardphog5vau

Novel Feed Network for Circular Polarization Antenna Diversity

Jung-Hoon Han, Noh-Hoon Myung
2014 IEEE Antennas and Wireless Propagation Letters  
In this letter, we propose a novel feed network for circular polarization (CP) diversity antennas to enhance communications performances. The previous CP diversity systems adopted dual polarization diversity using right-hand circular polarization (RHCP) and left-hand circular polarization (LHCP) within a small space. However, the same rotational CPs need further antenna distance. To overcome the space limitation for the same CP diversity antenna, we propose a feed network for CP antenna using
more » ... nventional CP with orthogonal polarization radiation characteristics of a linear polarization (LP) diversity system without additional antennas. The port isolation characteristics and impedance matching conditions are numerically verified for the diversity system and antenna characteristics. The proposed feed network with CP patch antennas is fabricated and measured in a reverberation chamber for diversity performances, and their validity is verified. Index Terms-Circular polarization, diversity, feed network, multiple-input-multiple-output (MIMO).
doi:10.1109/lawp.2014.2323399 fatcat:kxubr6ficncb5ad6v2mqojbqfa

AZIMUTH BEAM PATTERN SYNTHESIS FOR AIRBORNE SAR SYSTEM OPTIMIZATION

Sang-Ho Lim, Jung-Hoon Han, Se-Young Kim, Noh-Hoon Myung
2010 Electromagnetic Waves  
The limitation of the pulse repetition frequency (PRF) of an airborne synthetic aperture radar (SAR) system is not a serious problem to obtain high azimuth resolution and wide swath imaging compared with a spaceborne SAR system. Hence, continuous high azimuth resolution imagery over a wide area can be obtained using an antenna having a wide beamwidth. Since a small antenna with a large beamwidth has very low gain, which results in difficulty in detection; the azimuth beam pattern optimization
more » ... a large active phased array antenna is needed for airborne SAR system optimization. To improve the airborne SAR system performance, such as the noiseequivalent sigma zero (N Eσ 0 ), the azimuth resolution, the radiometric accuracy (RA), and the azimuth ambiguity ratio (AAR), we present an optimal azimuth beam pattern mask template and suggest an azimuth beam pattern satisfying the mask template using the particle swarm optimization (PSO). The mode having the proposed beam pattern guarantees continuous and high resolution images, simultaneously.
doi:10.2528/pier10061901 fatcat:kjniy7nwujbdrfmu3ermbzgb5m

Cortical Thickness Reduction in Individuals at Ultra-High-Risk for Psychosis

Wi Hoon Jung, June Sic Kim, Joon Hwan Jang, Jung-Seok Choi, Myung Hun Jung, Ji-Young Park, Ji Yeon Han, Chi-Hoon Choi, Do-Hyung Kang, Chun Kee Chung, Jun Soo Kwon
2009 Schizophrenia Bulletin  
Jung et al.  ...  The authors also gratefully acknowledge the technical support of Yong-Sik Jung, Kiho Im, and Sun Hyung Kim. Fig. 1 . 1 Mean Cortical Thickness in 3 Groups for Each Hemisphere.  ... 
doi:10.1093/schbul/sbp151 pmid:20026559 pmcid:PMC3122277 fatcat:luwdm3ex3jem3jqvu7kvssi534

CORRELATION ANALYSIS OF TWO SKEWED DIPOLES USING EMBEDDED BEAM PATTERNS

Jung-Hoon Han, Noh-Hoon Myung
2018 Progress In Electromagnetics Research C  
In this paper, the correlation coefficients of skewed dipole arrays for antenna diversity are theoretically analyzed for each polarization characteristic and in various propagation environments. The correlation is not simply increased by two closely located antennas with different polarization characteristics, nor is it decreased by increasing the distance between the antennas. This is interpreted from the correlation analysis of two skewed dipoles with different polarization characteristics.
more » ... e embedded beam patterns of the two skewed dipoles are calculated using the mutual impedances derived using the effective length vector (ELV) method; then, the mutually coupled correlation coefficients for θ, φ, and total polarizations are effectively derived. The correlations are also analyzed for various realistic propagation environments using statistical channel models with angular density functions, and cross polarization discriminations (XPDs). Finally, this paper provides an effective correlation analysis for two dipoles and proposes an optimal geometry for two skewed dipoles in various propagation environments for each polarization characteristic with environmental variables.
doi:10.2528/pierc18042604 fatcat:cszoopwvnnc7fjx3qgywevbqae
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