Publications by authors named "Seok-Hwan Park"

In the domain of Computer-Aided Diagnosis (CAD) systems, the accurate identification of cancer lesions is paramount, given the life-threatening nature of cancer and the complexities inherent in its manifestation. This task is particularly arduous due to the often vague boundaries of cancerous regions, compounded by the presence of noise and the heterogeneity in the appearance of lesions, making precise segmentation a critical yet challenging endeavor. This study introduces an innovative, an iterative feedback mechanism tailored for the nuanced detection of cancer lesions in a variety of medical imaging modalities, offering a refining phase to adjust detection results.

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Despite the potential benefits of reducing system costs and improving spectral efficiency, it is challenging to implement cloud radio access network (C-RAN) systems due to the performance degradation caused by finite-capacity fronthaul links and inter-cluster interference signals. This work studies inter-cluster cooperative reception for the uplink of a two-cluster C-RAN system, where two nearby clusters interfere with each other on the uplink access channel. The radio units (RUs) of two clusters forward quantized and compressed version of the uplink received signals to the serving baseband processing units (BBUs) via finite-capacity fronthaul links.

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In modern implementations of Cloud Radio Access Network (C-RAN), the fronthaul transport network will often be packet-based and it will have a multi-hop architecture built with general-purpose switches using network function virtualization (NFV) and software-defined networking (SDN). This paper studies the joint design of uplink radio and fronthaul transmission strategies for a C-RAN with a packet-based fronthaul network. To make an efficient use of multiple routes that carry fronthaul packets from remote radio heads (RRHs) to cloud, as an alternative to more conventional packet-based multi-route reception or coding, a multiple description coding (MDC) strategy is introduced that operates directly at the level of baseband signals.

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The objective of this study is to assess human exposure to phthalates and its associations with demographic characteristics of the subjects in the Korean National Human Biomonitoring Survey. The subjects aged between 18 and 69 were selected through nationwide stratified sampling. A total of 1874 urine samples were collected and stored at -20 °C until measurement for ten selected metabolites of phthalates (MnBP, MiBP, MBzP, MCHP, MnOP, MEHP, MEOHP, MEHHP, MiNP, and MiDP) using high-performance liquid chromatography-tandem mass spectrometry (LC-MS/MS).

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This study aimed to determine if there was an association between the implementation of smoking regulation policies and the urine cotinine concentrations of Korean non-smokers. The subjects of this study were 4612 non-smoking Korean citizens (aged 19 or older) selected from the first stage of the Korean National Environmental Health Survey conducted by the National Institute of Environmental Research from 2009 to 2011. Cotinine concentrations in urine were measured by GC-MS (limit of detection: 0.

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Hierarchically mesoporous CuO/carbon nanofiber coaxial shell-core nanowires (CuO/CNF) as anodes for lithium ion batteries were prepared by coating the Cu2(NO3)(OH)3 on the surface of conductive and elastic CNF via electrophoretic deposition (EPD), followed by thermal treatment in air. The CuO shell stacked with nanoparticles grows radially toward the CNF core, which forms hierarchically mesoporous three-dimensional (3D) coaxial shell-core structure with abundant inner spaces in nanoparticle-stacked CuO shell. The CuO shells with abundant inner spaces on the surface of CNF and high conductivity of 1D CNF increase mainly electrochemical rate capability.

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High temperature and pressure are generally required to produce biodiesel using supercritical methanol. We reduced the harsh reaction conditions by means of sonicating the reaction mixture prior to transesterification using supercritical methanol. Soybean oil was selected as the raw material for transesterification.

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Levodopa or L-3,4-dihydroxyphenylalanine (L-DOPA) is the precursor of the neurotransmitter dopamine. L-DOPA is a famous treatment for Parkinson's disease symptoms. In this study, electroenzymatic synthesis of L-DOPA was performed in a three-electrode cell, comprising a Ag/AgCl reference electrode, a platinum wire auxiliary electrode, and a glassy carbon working electrode.

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Background: Recently, there have been several nationwide episodes involving imported toys contaminated with toxic metals and environmental hormones. In addition, cadmium intoxication has occurred due to soil contamination with cadmium from abandoned metal mines.

Objectives: To investigate the distribution, extent and factors influencing the levels of toxic metals in the blood or urine of the Korean general population over twenty years of age, we studied the blood or urine concentrations of heavy metals in a representative sample of 5087 Koreans in 2008.

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In this study, pilot-scale experiments for the removal of nitrogen from sewage obtained from a county Y sewer system were performed using modified A(2)O processes. Using this approach, the total amount of nitrogen discharged during denitrification of the influent was average 38.6 mg/L and a level of average 10.

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Hydrogels are materials with the ability to swell in water through the retention of significant fractions of water within their structures. Owing to their relatively high degree of biocompatibility, hydrogels have been utilized in a host of biomedical applications. In an attempt to determine the optimum conditions for hydrogel synthesis by the free-radical polymerization of sorbitan methacrylate (SMA), the hydrogel used in this study was well polymerized under the following conditions: 50% (w/v) SMA as monomer, 1% (w/w) alpha, alpha'-azo-bis(isobutyro-nitrile) as thermal initiator, and 1% (w/w) ethylene glycol dimethacrylate as cross-liking agent.

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