• JSTS:Journal of Semiconductor Technology and Science
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• v.14 no.1
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• pp.29-33
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• 2014

In this paper, we report our numerical simulation on the electronic-optical properties of the phosphorescent organic light emitting diodes (PHOLEDs) devices. In order to calculate the electrical and optical characteristics such as the transport behavior of carriers, recombination kinetics, and emission property, we undertake the finite element method (FEM). Our model includes Poisson's equation, continuity equation to account for behavior of electrons and holes and the exciton continuity/transfer equation. We demonstrate that the refractive indexes of each material affect the emission property and the barrier height of the interface influences the behavior of charges and the generation of exciton.

• Journal of Korean Neurosurgical Society
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• v.60 no.1
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• pp.98-101
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• 2017

We report a case of primary intracranial malignant melanoma (PIMM) with extracranial metastases. The patient was an 82-year-old woman diagnosed with PIMM under the left cerebellar tentorium. We performed a tumor resection followed by gamma knife surgery. An magnetic resonance imaging at 11 months after surgery showed a local intracranial recurrence. At 12 months, vertebral metastasis was suspected, and 2-[fluorine-18]-fluoro-2-deoxy-D-glucose positron emission tomography/computed tomography (FDG-PET/CT) showed multiple extracranial metastases. She died at 13 months after surgery. Although extracranial metastases of PIMM are extremely rare, we should carefully follow up extracranial metastases together with intracranial ones, especially by FDG-PET/CT, even at an early asymptomatic stage.

• Journal of Environmental Science International
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• v.30 no.10
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• pp.863-877
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• 2021

While there a growing interest in Voluntary Carbon Disclosure (VCD), comparatively little is discussed whether the improved quality of voluntary carbon disclosure can lead to subsequent changes in a company's carbon reduction performance. Drawing on companies under the Korean Emission Trading Scheme (ETS) with the contents analysis of their sustainable reports, the present research seeks to address the existing knowledge gaps in the current literature on environmental disclosure. Findings empirically show that an increase in the voluntary carbon disclosure score is positively transformed into changes in carbon performance and further develop that the effect of voluntary carbon disclosure on carbon performance varies depending on changes in management capability with the moderation effect.

• Journal of the Korean Society for Precision Engineering
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• v.13 no.12
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• pp.114-119
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• 1996

In the case of surface cracked plate specimen, we can not measure the fracture toughness of ductile materials by the ASTM E 813 standard method. In this report, using the Acoustic Emission method, we found out crack initiation point and investigated fracture toughness which was calculated by FEM. The method used in this paper shows that fracture toughnes by using AE technique is reliable.

• Journal of The Korean Astronomical Society
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• v.56 no.1
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• pp.41-57
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• 2023

We measured temporal and emission properties of quiescent magnetars using archival Chandra and XMM-Newton data, produced a list of the properties for 17 magnetars, and revisited previously suggested correlations between the properties. Our studies carried out with a larger sample, better spectral characterizations, and more thorough analyses not only confirmed previously-suggested correlations but also found new ones. The observed correlations differ from those seen in other neutron-star populations but generally accord with magnetar models. Specifically, the trends of the intriguing correlations of blackbody luminosity (L_BB) with the spin-inferred dipole magnetic field strength (B_S) and characteristic age (τ_c) were measured to be L_BB ∝ B^1.5_S and L_BB ∝ τ^-0.6_c, supporting the twisted magnetosphere and magnetothermal evolution models for magnetars. We report the analysis results and discuss our findings in the context of magnetar models.

• Journal of Energy Engineering
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• v.23 no.3
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• pp.72-81
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• 2014

Intergovernmental Panel on Climate Change(IPCC) suggested the three methodology, Tier 1/2/3, considering with the accuracy and difficulty of greenhouse gas emission statistics according to the report determined as the international criterion. In Korea, the existing inventory building was made by the Top-down approach applying with the emission factors for transportation in the entire energy consumption, the emission factors were investigated under the domestic traffic situation which did not reflect by the continuing increase of vehicle and the change of road section. From the suggestion of IPCC, which it is estimated that the emission estimation of $CO_2$ in greenhouse gas emission could be calculated more accurate by the carbon content according to the fuel, the establishment of measures to respond to climate change from the latest greenhouse gas emissions statistics will be able to improve the accuracy of national statistics using monthly or seasonally the analysis of carbon content about the transportation fuels.

• Journal of the Korean Vacuum Society
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• v.14 no.4
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• pp.258-262
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• 2005

We report on the field emission properties from vertically aligned carbon nanotubes (CNTs) produced by a triode PECVD with a SiNx capping layer on metal catalyst. It is found that the CNTs density can be controlled by the capping layer thickness and decreases with increasing SiNx thickness. The CNT density of $\~$ 104/$cm^{2}$ exhibited highest electron emission characteristics, the threshold field of 1.2 V/$\mu$m and the current density of 0.17 mA/$cm^{2}$ at 3.6 V/$\mu$m. We have carried out investigation of electron emission stability under ambient gas of N2. The electron emission stability was improved with decreasing CNT density. Under $1\times$$10^{-5}$ Torr ambient pressure, the CNTs in 5 $\mu$m hole show electron emission current higher than $1\times$$10^{-4}$ A/cm2 and it's electron emission uniformity has $2\%$.

• Journal of Breast Cancer
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• v.21 no.4
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• pp.463-467
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• 2018

Metastasis from primary cancer to the thyroid is uncommon in breast cancer. Here we present a case of lobular breast carcinoma that metastasized to the thyroid. A 54-year-old woman without symptoms was admitted to our institution for staging of the lymph node above the left clavicle. An $^{18}F$-fluoro-deoxy-D-glucose positron emission tomography scan was performed for staging, and low uptakes were observed in the left supraclavicular and cervical lymph nodes. High uptake was seen in the posterior and lower left lobe of the thyroid. Histologic findings indicated lobular breast carcinoma (positive GATA3, loss of E-cadherin expression) metastatic to the thyroid with a luminal profile. Immunohistochemical analysis was negative for primary thyroid or parathyroid carcinoma. To our knowledge, this is the first report of a patient presenting a metastatic invasive lobular carcinoma in the thyroid and lymph nodes without a prior diagnosis of breast cancer.

• Investigative Magnetic Resonance Imaging
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• v.23 no.1
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• pp.75-80
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• 2019

Metastasis of rhabdomysarcoma to the breast is a very rare manifestation in adult males. Herein, we report a case of metastasis from embryonal rhabdomyosarcoma in the left hypothenar muscle that presented as a breast mass in a 38-year-old man, who four months later expired because of multiple bone metastases related to pancytopenia. We describe the various imaging findings, including mammograms, ultrasonography, computerized tomography (CT), positron emission tomography-computed tomography (PET-CT), and magnetic resonance imaging (MRI) of this rare disease. The various imaging findings of this lesion could be helpful for future diagnosis of male breast lesions.

• Bulletin of the Korean Space Science Society
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• 2004.04a
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• pp.51-51
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• 2004

KAISTSAT-4 is to be launched in August 2003 into an orbit at 800 km altitude with the intended mission shared between astrophysics and space physics. The primary objective of its astrophysics mission is to provide spectral sky survey data of hot Galactic plasmas in the far-ultraviolet wavelength range. Far-Ultraviolet Imaging Spectrograph (FIMS) is sensitive to emission line fluxes in 900 - 1175 $\AA$ and 1335 - 1750 $\AA$. (omitted)