• Korean Journal of Remote Sensing
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• v.39 no.5_4
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• pp.1173-1183
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• 2023

Over the past 20 years, Korea's overall import and export cargo volume has increased at an average annual rate of approximately 5.3%. About 99% of the cargo is still being transported by sea. Due to recent increases in maritime cargo volume, congestion in maritime logistics has become challenging due to factors such as the COVID-19 pandemic and conflicts. Continuous monitoring of ports has become crucial. Various ground observation systems and Automatic Identification System (AIS) data have been utilized for monitoring ports and conducting numerous preliminary studies for the efficient operation of container terminals and cargo volume prediction. However, small and developing countries' ports face difficulties in monitoring due to environmental issues and aging infrastructure compared to large ports. Recently, with the increasing utility of artificial satellites, preliminary studies have been conducted using satellite imagery for continuous maritime cargo data collection and establishing ocean monitoring systems in vast and hard-to-reach areas. This study aims to visually detect ships docked at berths in the Busan New Port using high-resolution satellite imagery and quantitatively evaluate berth utilization rates. By utilizing high-resolution satellite imagery from Compact Advanced Satellite 500-1 (CAS500-1), Korea Multi-Purpose satellite-3 (KOMPSAT-3), PlanetScope, and Sentinel-2A, ships docked within the port berths were visually detected. The berth utilization rate was calculated using the total number of ships that could be docked at the berths. The results showed variations in berth utilization rates on June 2, 2022, with values of 0.67, 0.7, and 0.59, indicating fluctuations based on the time of satellite image capture. On June 3, 2022, the value remained at 0.7, signifying a consistent berth utilization rate despite changes in ship types. A higher berth utilization rate indicates active operations at the berth. This information can assist in basic planning for new ship operation schedules, as congested berths can lead to longer waiting times for ships in anchorages, potentially resulting in increased freight rates. The duration of operations at berths can vary from several hours to several days. The results of calculating changes in ships at berths based on differences in satellite image capture times, even with a time difference of 4 minutes and 49 seconds, demonstrated variations in ship presence. With short observation intervals and the utilization of high-resolution satellite imagery, continuous monitoring within ports can be achieved. Additionally, utilizing satellite imagery to monitor changes in ships at berths in minute increments could prove useful for small and developing country ports where harbor management is not well-established, offering valuable insights and solutions.

• The Korean Journal of Nuclear Medicine Technology
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• v.17 no.2
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• pp.31-36
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• 2013

Purpose: Measure gastric emptying time (GET: Gastric Emptying Time) is a non-invasive and quantitative evaluation methods, mainly by endoscopic or radiological examination confirmed no mechanical obstruction in patients with symptoms of congestion is checked. Such tests are not common gastric emptying time measured esophageal cancer patients (who underwent esophagectomy) patients after surgery for gastric emptying time was measured test. And the period of time for more than one year after the gastric emptying time measurement was performed. By comparing the two kinds of tests in the chest cavity after surgery as the evaluation of gastrointestinal function tests evaluate the usefulness of GET, and will evaluate the characteristics of the image. Materials and Methods: 93 patients who underwent esophagectomy with gastric emptying time measurement of subject tests immediately after surgery and after 1 year or longer were twice. Preparation of the patient before the test is more than 12 hours of overnight fasting is important, in addition to the medicine or to stop smoking, and diabetes insulin injections should be early in the morning is ideal to test. Generally labeled with $^{99m}Tc-DTPA$ resin which is used to make steamed egg, seaweed and fermented milk with a high viscosity after eating, three hours in the standing position was measured. Evaluation of gastric emptying curves on the way intragastric radioactivity level by 50% the time (half-time [T1/2]) was calculated, based on the half-life was divided into three steps: over 180 minutes was defined as delayed gastric emptying, within 180minutes was defined as intermediate gastric emptying and when all the radioisotopes were dumped into the jejunum as soon as swallowed, was defined as rapid gastric emptying. Results: Gastric emptying time of a typical images stomach of antrum and fundus additional images appear stronger over time move on to the small intestine. but esophageal cancer who underwent esophagectomy side of the thoracic cavity showed a strong image. Immediately after surgery, the half-time (T1/2) of rapid gastric emptying appeared to 12.9%, intermediate gastric emptying appeared to 52.7%, delay gastric emptying appeared to 34.4%. After more than a year the results of the half-life after surgery, 67% of rapid gastric emptying to intermediate gastric emptying was changed, 69% of delay gastric emptying to intermediate gastric emptying changed. Intermediate gastric emptying worse in patients rapid gastric emptying and the delay gastric emptying is 24% in the case. Conclusion: Esophagectomy for esophageal cancer who underwent half-time measurement test (T1/2) rapid gastric emptying and delay gastric emptying are the result of the comparison over time, changes were observed intermediate gastric emptying. Mainly seeing of gastric emptying time measurement in the esophagus instead of thoracic cavity to check the evaluation of gastrointestinal function can be useful even means. And segmentation criteria and narrow time interval of checking if more accurate information and analysis of the clinical diagnosis and evaluation seems to be done.