• Journal of Neurocritical Care
• /
• v.11 no.2
• /
• pp.86-92
• /
• 2018

Background: A delay of transfer for patients with acute stroke needing emergent revascularization is a huge hurdle for efficacy of revascularization. The objective of this study was to investigate changes of transportation time calculated by image to door (ITD) time (from checking brain images at first contact hospital to arriving at our emergency center) before and after 2015. Methods: This study was performed in a retrospective manner from 2013 into 2017. Acute ischemic stroke (AIS) patients having intravenous thrombolysis and/or mechanical thrombectomy during the observation period were enrolled. Among them, those who had revascularization under 'Drip-and-Ship' or 'Ship-and-Drip' paradigm were selected. Results: During the observation period, 225 patients were treated under 'Drip-and-Ship' or 'Ship-and-Drip' paradigm. Twenty-three were excluded due the lack of detailed data. Among 202 patients, 73 and 129 were treated under Drip-and-Ship and Ship-and-Drip paradigms, respectively. In 2013, 35 patients from 18 hospitals (median distance, 25 km) were transferred to our regional stroke center and their median ITD time was 116 minutes. It was gradually decreased after 2015. In 2017, ITD time was significantly (P<0.01) shortened to 85 minutes without significant changes in transfer distance. The median onset to puncture time was also significantly (P=0.03) decreased from 365 minutes in 2013 to 270 minutes in 2017. Conclusion: Our results implicate that many hospitals in our stroke region might have recognized the importance of rapid transportation for AIS after 2015.

• Journal of Preventive Medicine and Public Health
• /
• v.56 no.2
• /
• pp.145-153
• /
• 2023

Objectives: Although it is difficult to define the quality of stroke care, acute ischemic stroke (AIS) patients with moderate-to-severe neurological deficits may benefit from thrombectomy-capable hospitals (TCHs) that have a stroke unit, stroke specialists, and a substantial endovascular thrombectomy (EVT) case volume. Methods: From national audit data collected between 2013 and 2016, potential EVT candidates arriving within 24 hours with a baseline National Institutes of Health Stroke Scale score ≥6 were identified. Hospitals were classified as TCHs (≥15 EVT case/y, stroke unit, and stroke specialists), primary stroke hospitals (PSHs) without EVT (PSHs-without-EVT, 0 case/y), and PSHs-with-EVT. Thirty-day and 1-year case-fatality rates (CFRs) were analyzed using random intercept multilevel logistic regression. Results: Out of 35 004 AIS patients, 7954 (22.7%) EVT candidates were included in this study. The average 30-day CFR was 16.3% in PSHs-without-EVT, 14.8% in PSHs-with-EVT, and 11.0% in TCHs. The average 1-year CFR was 37.5% in PSHs-without-EVT, 31.3% in PSHs-with-EVT, and 26.2% in TCHs. In TCHs, a significant reduction was not found in the 30-day CFR (odds ratio [OR], 0.92; 95% confidence interval [CI], 0.76 to 1.12), but was found in the 1-year CFR (OR, 0.84; 95% CI, 0.73 to 0.96). Conclusions: The 1-year CFR was significantly reduced when EVT candidates were treated at TCHs. TCHs are not defined based solely on the number of EVTs, but also based on the presence of a stroke unit and stroke specialists. This supports the need for TCH certification in Korea and suggests that annual EVT case volume could be used to qualify TCHs.

• Convergence Security Journal
• /
• v.23 no.2
• /
• pp.37-45
• /
• 2023

Cyber deception technology plays a crucial role in monitoring attacker activities and detecting new types of attacks. However, along with the advancements in deception technology, the development of Anti-honeypot technology has allowed attackers who recognize the deceptive environment to either cease their activities or exploit the environment in reverse. Currently, deception technology is unable to identify or respond to such situations. In this study, we propose a predictive model using Markov chain analysis to determine the identification of attackers who infiltrate deceptive environments. The proposed model for deception status determination is the first attempt of its kind and is expected to overcome the limitations of existing deception-based attacker analysis, which does not consider attackers who identify the deceptive environment. The classification model proposed in this study demonstrated a high accuracy rate of 97.5% in identifying and categorizing attackers operating in deceptive environments. By predicting the identification of an attacker's deceptive environment, it is anticipated that this model can provide refined data for numerous studies analyzing deceptive environment intrusions.

• Journal of the Korean Society for Marine Environment & Energy
• /
• v.16 no.1
• /
• pp.1-8
• /
• 2013

This study focuses on a ship detection and tracking method using Frequency Modulated Continuous Wave (FMCW) radar used for horizontal surveillance. In general, FMCW radar can play an important role in maritime surveillance, because it has many advantages such as low warm-up time, low power consumption, and its all weather performance. In this paper, we introduce an effective method for data and signal processing of ship's detecting and tracking using the X-band radar. Ships information was extracted using an image-based processing method such as the land masking and morphological filtering with a threshold for a cycle data merged from raw data (spoke data). After that, ships was tracked using search-window that is ship's expected rectangle area in the next frame considering expected maximum speed (19 kts) and interval time (5 sec). By using this method, the tracking results for most of the moving object tracking was successful and those results were compared with AIS (Automatic Identification System) for ships position. Therefore, it can be said that the practical application of this detection and tracking method using FMCW radar improve the maritime safety as well as expand the surveillance coverage cost-effectively. Algorithm improvements are required for an enhancement of small ship detection and tracking technique in the future.

• Journal of the Korean Society of Marine Environment & Safety
• /
• v.21 no.2
• /
• pp.179-187
• /
• 2015

The purpose of this study is to identify the aspect that the traffic distribution function changes, according to the direction of the datum line and the horizontal and vertical positions of the datum point applied when it is calculated. Targeting routes at the entrance of Mokpo Harbor, this study tested using AIS survey data of January 2013 the effects of the three variables-direction of the datum line(${\theta}$), horizontal position($\mathfrak{L}_H$) and vertical position($\mathfrak{L}_V$) on mean ($\bar{x}$) and standard deviation (${\delta}$). The test result showed that $\bar{x}$ and ${\delta}$ were changed according to the change of ${\theta}$, because the extracted sample data were changed according to ${\theta}$; and the changes of $\bar{x}$ and ${\delta}$ according to ${\theta}$ were drawn as the relation of the sine function' sum. In addition, it was found that setting up ${\theta}$ that the change value of ${\delta}$ becomes the least as the direction of the datum line was valid, to determine the optimum passage distribution function on complex waters with multiple branches of route. The result of this study is expected to be used as basic data to understand maritime traffic flow based on more quantified data of normal distribution and make decisions related to maritime traffic safety management.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
• /
• 2016.10a
• /
• pp.243-246
• /
• 2016

Data transfer technique is one of the key elements of the IT infrastructure, in accordance with each environment and function, using some kind of protocol. Using the three protocols such as WCDMA, AIS, and TRS at sea IT industry. so It uses three protocols saw has a problem that the operation of each protocol-specific server. so server maintenance costs increase and sea Device Manager has been placed in a situation which operates to develop each of the protocol-specific analysis program. The reason of the protocol is divided into three, marine equipment (lighthouses, buoys, light buoy) manufacturing companies and the date of manufacture, such as, communication environment (distance, communication speed) because such is wrong all, trying to unify this and enormous cost and time is a situation that can not be the exchange occurred when. So in the Ministry of Maritime Affairs and Fisheries, the number of frequency of use is low, communication performance is seeking to refrain from Kure each local organizations and companies the use of low TRS protocol. his paper is intended to conduct research on the basis of the actual data to analyze whether the method is how economical to store a single DB by analyzing other types of protocols. This reduces the shortage of marine IT industry, even a little, shall helps reduce administrative costs.

• The Journal of the Korea institute of electronic communication sciences
• /
• v.6 no.6
• /
• pp.815-822
• /
• 2011

In this paper, a design and implemented of the data communication system on the entails inherent safety with the distress and urgency of maritime data communication services that are required for functional limitations of the existing mounting equipment and services to determine the likelihood MF/HF, VHF, Inmarsat satellite communication has a diversification of the GMDSS ship communication equipment. Proposed role and direction of the GMDSS on the communication media by the communication cost, throughput, communication speed and processing services available, communication range, etc. by conducting a performance analysis and evaluation in the future maritime communications environment.

• The Korean Journal of Air & Space Law and Policy
• /
• v.17
• /
• pp.91-110
• /
• 2003

Aeronautical Information Service means a service established within the defined area of coverage responsible for the provision of aeronautical information/data necessary for the safety, regularity and efficiency of air navigation. Especially, in consequence of RNAV envelopment, the role and importance of aeronautical information/data has been increased constantly, therefore advanced RNP and navigation systems has been highly required simultaneously. International Civil Aviation Organization establishes SARPs to maintain aviation safety for every contracting states. Therefore, every contracting states should make an application of the aviation information and data in accordance with ICAO's SARPs, but each state is actually applied with each other regulations considered with each state's circumstance. At the result of these reason, it sometimes makes confuse to aircraft operator and effects significant aviation safety. The purpose of this study is to investigate SARPs of Annexes and rules of FAA relevant to Aeronautical Information Service(AIS), to compare them with Korean Aviation law and regulations related to AIS and then, to provide information for planing and decision-making to enhance them into the international standards.

• Journal of the Korean Institute of Intelligent Systems
• /
• v.26 no.3
• /
• pp.239-245
• /
• 2016

In the midst of continuing international recession, the rate of maritime traffic and marine leisure markets are consistently growing. The Republic of Korea controls the marine traffic volume through vessel traffic centers and various other management facilities. Nevertheless, the continuous growth and complexity of marine traffic is resulting in repeated occurrences of marine accidents. Recovery is very difficult in cases of human injuries or deaths caused by marine accidents due to its nature, and the scale of marine accidents is also becoming greater with advanced ship building technologies. Passenger ships, oil tankers, and other such vessels used for specific purposes requires a more detailed navigational status surveillance and analysis, and numerous research has been conducted with an objective for monitoring such special purpose vessels. However, the data elements transmitted from the ocean to the shore station are limited to AIS and ARPA. We are implementing IoT ship sensor collection and a syncing system capable of transmitting various ship sensing data to the shore station, and also proposing a Safe Navigation Status Analysis System utilizing the collected data.

• Journal of the Korean Society of Marine Environment & Safety
• /
• v.20 no.2
• /
• pp.193-201
• /
• 2014

This study provided safe sailing speed and appropriate passing time to areas of known strong current water to prevent marine accident of the ships. To the interpretation of these data which target Myeongnyang waterway, AIS data of the ship was collected from $12^{th}$ July to $15^{th}$ July 2010 and site environment was investigated on $4^{th}$ September 2010. On the basis of the collected data, the 'Minimum Navigation Speed' and 'Optimum Navigation Speed' were calculated. It has also considered the 'Spare control force' or allowance and the 'Respond Rudder Angle' for each tidal current speed. Additionally, it suggested the safe passing time to strong current area by analyzing tidal level and tidal current speed. The conclusion of the research are as follows : (1) If the flow rate is greater than 4.4 kn, it is difficult for the model ship to control herself by her own steering power and to cope with tidal current pressure force and yaw moment caused by the tidal current.. (2) The minimum navigation speed should be over 2.3 times the tidal current and the optimum navigation speed should be over 4.0 times the tidal current. (3) When spring tide, the optimum passing time at Myeongnyang waterway is between 30 minutes to 1 hour before the time of high/low water, and at 5 hours after high/low water, passing of ships should be avoided because it is time when the flow rate is over 4 kn.