이준행 교수

Deep spiking neural networks (SNNs) hold the potential for improving the latency and energy efficiency of deep neural networks through data-driven event-based computation. However, training such networks is difficult due to the non-differentiable nature of spike events. In this paper, we introduce a novel technique, which treats the membrane potentials of spiking neurons as differentiable signals, where discontinuities at spike times are considered as noise. This enables an error backpropagation

Although gastric cancer is quite common in Korea, the treatment outcome is relatively favorable compared to those in western countries. However, there are currently no Korean multidisciplinary guidelines for gastric cancer. Experts from related societies developed guidelines de novo to meet Korean circumstances and requirements, including 23 recommendation statements for diagnosis (n=9) and treatment (n=14) based on relevant key questions. The quality of the evidence was rated according to the G

BACKGROUND AND AIMS: Although triple combination therapy containing a proton pump inhibitor (PPI) and two antibiotics is considered as a standard regimen for the first-line anti-Helicobacter pylori treatment, there are still debates on the ideal duration of treatment. The aim of this study was to compare the efficacies of 7-day and 14-day PPI-containing triple therapy. MATERIALS AND METHODS: This study was performed in a randomized, multicenter, prospective manner. After upper gastrointestinal e

BACKGROUND AND AIM: To perform endoscopic mucosal resection (EMR) for T1 esophageal cancer, it is essential to estimate the lymph node status exactly. In order to evaluate the feasibility of EMR for esophageal cancers, we evaluated the clinicopathological features of T1 esophageal squamous carcinomas with an emphasis on the risk factors and distribution patterns of lymph node metastasis. METHODS: From 1994 to 2006, a total of 200 patients with T1 esophageal carcinoma were treated surgically in o

We propose a real-time hand gesture interface based on combining a stereo pair of biologically inspired event-based dynamic vision sensor (DVS) silicon retinas with neuromorphic event-driven postprocessing. Compared with conventional vision or 3-D sensors, the use of DVSs, which output asynchronous and sparse events in response to motion, eliminates the need to extract movements from sequences of video frames, and allows significantly faster and more energy-efficient processing. In addition, the

When patients with very localized lower abdominal pain and tenderness do not have associated symptoms or laboratory abnormalities, a high index of suspicion for PEA and early radiologic examinations are required.

OBJECTIVES: Nonpolypoid adenomas, which can be important precursors of colorectal cancers, are difficult to find during routine colonoscopy. The aim of this study was to evaluate the usefulness of routine chromoendoscopy in Korea, where the incidence of colorectal cancer is low compared with western countries. METHODS: Colonoscopy with chromoendoscopy was performed in 74 consecutive patients (48 men, 26 women; mean age 53.0 yr). After a careful examination of the whole colon, a defined segment o

BACKGROUND AND AIM: Two percent glutaraldehyde, the most widely used liquid chemical germicide (LCG), may be hazardous to patients and medical personnel. Alternatives to glutaraldehyde, such as electrolyzed acid water (EAW), are being developed, but data from well-controlled studies with patient-used endoscopes are rare. The purpose of the present paper was to evaluate the high-level disinfection capability of EAW and compare it with glutaraldehyde. METHODS: A random sample of 125 endoscopes was

Endoscopic mucosal resection (EMR) has been established as one of the treatment options for early gastric cancer (EGC). However, there are many uncertain areas such as indications of EMR, best treatment methods, management of complications and follow-up methods after the procedure. Most studies on this topic have been carried out by researchers in Japan. In Korea, gastric cancer is the most common malignant disease, and the second leading cause of cancer death. In these days, EMR for EGC is wide

Although, gastric cancer is quite common in Korea, the treatment outcome is relatively favorable compared to that of Western countries. However, there is no Korean multidisciplinary guideline for gastric cancer and thus, a guideline adequate for domestic circumstances is required. Experts from related societies developed 22 recommendation statements for the diagnosis (n=9) and treatment (n=13) based on relevant key questions. Evidence levels based on systematic review of literatures were classif

Non-steroidal anti-inflammatory drugs (NSAIDs) are among the most commonly used medications in Korea. Gastrointestinal toxicity, including peptic ulcer, is a common adverse effect of NSAIDs. Risk factors for NSAID-related peptic ulcer include a previous history of peptic ulcer, advanced age, high dose, concomitant use of corticosteroids, anticoagulants, other NSAIDs including low-dose aspirin. Preventive measure(s), such as COX-2 inhibitor, proton pump inhibitor or misoprostrol, should be done f

BACKGROUND AND AIM: At least half of the patients with typical reflux symptoms have non-erosive reflux disease (NERD). Minimal change lesions are commonly seen in the screening endoscopic examinations for individuals without clinically significant symptoms. We evaluated the correlation between minimal changes and symptoms in individuals visiting the hospital for routine health check-up by a nationwide survey in 2006. METHODS: Upper gastrointestinal endoscopic examinations as a health check-up we