Jung-Ho Choi

Learn More
Estimating printing source is applicable in many forensic situations. In this paper, we propose an electrophotographic printer identification scheme from its printed material, in which imperceptible halftone patterns are contained inherently. The halftone textures in each channel of CMYK domain are analyzed. We construct a histogram from angle values of(More)
Color laser printers are nowadays abused to print or forge official documents and bills. Identifying color laser printers will be a step for media forensics. This paper presents a new method to identify color laser printers with printed color images. First, 39 noise features of color printed images are extracted from the statistical analysis of the HH(More)
BACKGROUND/OBJECTIVES This study was performed to investigate the in vitro antioxidant and cytoprotective effects of fermented sesame sauce (FSeS) against hydrogen peroxide (H2O2)-induced oxidative damage in renal proximal tubule LLC-PK1 cells. MATERIALS/METHODS 1,1-diphenyl-2-picrylhydrazyl (DPPH), hydroxyl radical ((•)OH), and H2O2 scavenging assay was(More)
—This paper proposes a steganalysis scheme using the difference histogram and image calibration. The message embedding makes the correlation with the neighboring pixels weaken and the random changes of the pixel values generate the block effects among the pixels. The proposed method crops a suspicious image by 1 pixel in a row or column direction and(More)
The objective of this study was to develop a Korean version of the Assessment of Spondyloarthritis International Society-Health Index/Environmental Factor (ASAS HI/EF) and to evaluate its reliability and validity in Korean patients with axial spondyloarthritis (SpA). A total of 43 patients participated. Translation and cross-cultural adaptation of the ASAS(More)
INTRODUCTION Gout is characterized by episodes of intense joint inflammation in response to intra-articular monosodium urate monohydrate (MSU) crystals. miR-155 is crucial for the proinflammatory activation of human myeloid cells and antigen-driven inflammatory arthritis. The functional role of miR-155 in acute gouty arthritis has not been defined.(More)
  • Frank Zhou, Douglas Skinner, Philip Berger, Richard Hahn, Haresh, Ray Ball +23 others
  • 2016
This paper examines the effects of investor learning on the dynamics of managers' voluntary disclosure decisions. Using a multi-period voluntary disclosure model and structural estimation, I find that investor learning introduces persistence in disclosure incentives because of the correlation of investors' beliefs over time. Disclosure is more likely when(More)
BACKGROUND/AIMS Percutaneous coronary intervention (PCI) is often performed therapeutically, and antithrombotic treatment is required for at least 12 months after stent implantation. However, the development of post-PCI upper gastrointestinal bleeding (UGIB) increases morbidity and mortality. We investigated the incidence and risk factors for UGIB in Korean(More)
A foreign body in heart is rare, but it is more frequently encountered than the past as iatrogenic causes are increasing. Clinicians should be aware that foreign body could be mistaken for normal structure of heart. In order for accurate diagnosis, multi-imaging modalities should be used for information of exact location, mobility and hemodynamic effects. A(More)
Constrictive pericarditis is an uncommon post-inflammatory disorder characterized by a variably thickened, fibrotic, and frequently calcified, pericardium. Etiology of the constriction can occur for many reasons. Although foreign bodies are not the common cause of constrictive pericarditis, the long-term presence of foreign bodies, like bullets, is presumed(More)