• Korean Journal of Remote Sensing
• /
• v.38 no.5_1
• /
• pp.523-533
• /
• 2022

This paper presents a two-stage spatio-spectral fusion method (2SSFM) based on area-to-point regression kriging (ATPRK) to enhance spatial and spectral resolutions using multi-sensor satellite images with complementary spatial and spectral resolutions. 2SSFM combines ATPRK and random forest regression to predict spectral bands at high spatial resolution from multi-sensor satellite images. In the first stage, ATPRK-based spatial down scaling is performed to reduce the differences in spatial resolution between multi-sensor satellite images. In the second stage, regression modeling using random forest is then applied to quantify the relationship of spectral bands between multi-sensor satellite images. The prediction performance of 2SSFM was evaluated through a case study of the generation of red-edge and short-wave infrared bands. The red-edge and short-wave infrared bands of PlanetScope images were predicted from Sentinel-2 images using 2SSFM. From the case study, 2SSFM could generate red-edge and short-wave infrared bands with improved spatial resolution and similar spectral patterns to the actual spectral bands, which confirms the feasibility of 2SSFM for the generation of spectral bands not provided in high spatial resolution satellite images. Thus, 2SSFM can be applied to generate various spectral indices using the predicted spectral bands that are actually unavailable but effective for environmental monitoring.

• Korean Journal of Remote Sensing
• /
• v.39 no.1
• /
• pp.77-86
• /
• 2023

Ship detection is widely used in areas such as maritime security, maritime traffic, fisheries management, illegal fishing, and border control, and ship detection is important for rapid response and damage minimization as ship accident rates increase due to recent increases in international maritime traffic. Currently, according to a number of global and national regulations, ships must be equipped with automatic identification system (AIS), which provide information such as the location and speed of the ship periodically at regular intervals. However, most small vessels (less than 300 tons) are not obligated to install the transponder and may not be transmitted intentionally or accidentally. There is even a case of misuse of the ship'slocation information. Therefore, in this study, ship detection was performed using high-resolution optical satellite images that can periodically remotely detect a wide range and detectsmallships. However, optical images can cause false-alarm due to noise on the surface of the sea, such as waves, or factors indicating ship-like brightness, such as clouds and wakes. So, it is important to remove these factors to improve the accuracy of ship detection. In this study, false alarm wasreduced, and the accuracy ofship detection wasimproved by removing wake.As a ship detection method, ship detection was performed using machine learning-based random forest (RF), and convolutional neural network (CNN) techniquesthat have been widely used in object detection fieldsrecently, and ship detection results by the model were compared and analyzed. In addition, in this study, the results of RF and CNN were combined to improve the phenomenon of ship disconnection and the phenomenon of small detection. The ship detection results of thisstudy are significant in that they improved the limitations of each model while maintaining accuracy. In addition, if satellite images with improved spatial resolution are utilized in the future, it is expected that ship and wake simultaneous detection with higher accuracy will be performed.

• Journal of Veterinary Science
• /
• v.23 no.2
• /
• pp.20.1-20.8
• /
• 2022

Background: Emergent and re-emergent canine tick-borne infections are attracting increasing attention worldwide. The rise in pet ownership and the close relationship between dogs and their owners are the most concerning factors because dogs may act as competent reservoirs for human tick-transmitted infectious agents. Objectives: This study contributes to the epidemiological surveillance of canine tick-transmitted infections with zoonotic risk in the Republic of Korea (ROK) by investigating the seroprevalence of the pathogens, Anaplasma spp., Borrelia burgdorferi, and Ehrlichia canis. Methods: Four hundred and thirty whole blood samples from domestic dogs were collected in seven metropolitan cities and nine provinces in the ROK and tested using SensPERT Ab test kits (VetAll Laboratories^®) to detect seroreactive animals. Results: The seroprevalence rates identified were 9.8% (42/430) for Anaplasma spp., 2.8% (12/430) for B. burgdorferi, and 1.4% (6/430) for E. canis. The risk factors evaluated in this study that could be associated with the development of a humoral immune response, such as sex, age, and history of tick exposure, were similar. There was only one exception for dogs seroreactive to Anaplasma spp., where the risk factor "tick exposure" was statistically significant (p = 0.047). Conclusions: This serological survey exhibited the widespread presence of Anaplasma spp., B. burgdorferi, and E. canis throughout the ROK. Hence, dogs may play a key role as the sentinel animals of multiple zoonotic infectious agents in the country.

• The Korean Journal of Nuclear Medicine Technology
• /
• v.13 no.1
• /
• pp.25-29
• /
• 2009

Purpose: Several radioactive agents were used for lymphoscintigraphy in breast cancer. But recently, due to the change of local radiopharmaceutical licensing policy and discontinuation of supplies from manufacturer, we could not use many radiocolloids such as $^{99m}Tc$-Antimony Trisulfide Colloid, $^{99m}Tc$-Tin Colloid, $^{99m}Tc$-Human Serum Albumin. So it is necessary to use the substitution radiopharmaceutical. Therefore, this study aims to evaluate the performance of substitution radiopharmaceutical ($^{99m}Tc$-Phytate) including the existing radiocolloids and to set up of the appropriate protocol in lymphoscintigraphy. Materials and Methods: For each radiocolloids ($^{99m}Tc$-Antimony Trisulfide Colloid (ASC), $^{99m}Tc$-Tin Colloid (TC), $^{99m}Tc$-Human Serum Albumin (HSA), $^{99m}Tc$-Phytate) were performed the particle size by Zeta Sizer (Nano-ZS) and we compared the radiolabeling time, procedure and acquisition time for each of the radiocolloids (total 200 patients). For the last time, we made an analysis of image for each of the radiocolloids with our previous report (SJ Jang et al, Korean Nucl Med Mol imaging Vol.41, No.6, Dec 2007). Results: The particle size of each radiocolloids showed A.S.C (50 nm), T.C (310 nm), H.S.A (10.8 nm), $^{99m}Tc$-Phytate (499 nm). The labeling and acquisition time for each of the radiocolloids showed no substantial difference. But there is difference of the labeling time for the A.S.C. because the ASC procedure need to boiling process. There were no significant differences among those radiocolloids (p>0.005) in the identification rate (IR), false negative rate (FNR), and negative predictive value (NPV). Conclusions: $^{99m}Tc$-labeled radiocolloids showed equivalent results in lymphoscintigraphy. Therefore, in this exam of each radiocolloids could be applied appropriate protocol in lymphoscintigraphy.

• Journal of Korean Society of Occupational and Environmental Hygiene
• /
• v.28 no.3
• /
• pp.283-291
• /
• 2018

Objectives: To monitor the radon concentration level in plants that handle phosphorus rock and produce gypsum board and cement, and evaluate the effective dose considering the effect of radon exposure on the human body. Methods: Airborne radon concentrations were measured using alpha-track radon detectors (${\alpha}$-track, Rn-tech Co., Korea) and continuous monitors (Radon Sentinel 1030, Sun Nuclear Co., USA). Radon concentrations in the air were converted to radon doses using the following equation to evaluate the human effects due to radon. H (mSv/yr) = Radon gas concentration x Equilibrium factor x Occupancy factor x Dose conversion factor. The International Commission on Radiological Protection (ICRP) used $8nSv/(Bq{\cdot}hr/m^3)$ as the dose conversion factor in 2010, but raised it by a factor of four to $33nSv/(Bq{\cdot}hr/m^3)$ in 2017. Results: Radon concentrations and effective doses in fertilizer manufacturing process averaged $14.3(2.7)Bq/m^3$ ($2.0-551.3Bq/m^3$), 0.11-0.54 m㏜/yr depending on the advisory authority and recommendation year, respectively. Radon concentrations in the gypsum-board manufacturing process averaged $14.9Bq/m^3$ at material storage, $11.4Bq/m^3$ at burnability, $8.1Bq/m^3$ at mixing, $10.0Bq/m^3$ at forming, $8.9Bq/m^3$ at drying, $14.7Bq/m^3$ at cutting, and $10.5Bq/m^3$ at shipment. It was low because it did not use phosphate gypsum. Radon concentrations and effective doses in the cement manufacturing process were $23.2Bq/m^3$ in the stowage area, $20.2Bq/m^3$ in the hopper, $16.8Bq/m^3$ in the feeder and $11.9Bq/m^3$ in the cement mill, marking 0.12-0.63 m㏜/yr, respectively. Conclusions: Workers handling phosphorous gypsum directly or indirectly can be assessed as exposed to an annual average radon dose of 0.16 to 2.04 mSv or 0.010 to 0.102 WLM (Working Level Month).

• Journal of the Korean Institute of Landscape Architecture
• /
• v.47 no.2
• /
• pp.100-116
• /
• 2019

Urban green spaces, as a means to mitigate social problems and environmental risks, are getting more attention in evaluating urban environment. The inequity of green space distribution is becoming a major issue in urban planning and management. This study investigated the characteristics of green space in 3 districts (Jung-gu, Dongdaemun-gu, Seongdong-gu), that are composed of 46 administrative divisions in central Seoul, to analyze the environmental equity of urban green spaces. The correlations between the amount of green space, including the coverage of street trees, and the socioeconomic status of each administrative division were analyzed. To deduce the effects of plant coverage on the urban temperature regime, the relationship between the normalized difference of vegetation index (NDVI) and land surface temperature (LST) was analyzed. The research revealed that the mean NDVI of an administrative division was negatively correlated with the percentage of basic living recipients and disabled people. The LST of a division with low NDVI was higher due to the lack of green coverage. Such environmental inequities were closely related to residential building type, which was strongly affected by the economic status of residents. The LST of an apartment area was $2.0^{\circ}C$ lower than that of single-family houses and multi-housing areas. This is expected as the average NDVI of the apartment area was more than twice as high as the other environments considered in this study. The inequity can be exacerbated without urban planning which is deliberately designed to reduce it.

• Korean journal of applied entomology
• /
• v.57 no.4
• /
• pp.381-392
• /
• 2018

The distribution of mosquitoes collected in the Cheongju area from 2016-2018 were compared. The collection sites were established at a residential area, migratory bird sanctuary, and cowshed using black light (BL) and BG sentinel traps. Culex pipiens was the most collected species in the residential area, and Aedes vexans was the most collected species in the migratory bird sanctuary and cowshed in all years. The BG trap collected more individuals than did the BL trap in the residential area and migratory bird sanctuary. In total, 22,679 (10 species) mosquitoes were collected in 2016, and 6,502 (8 species) and 6,803 (9 species) mosquitoes were collected in 2017 and 2018, accounting for 3.49- and 3.33-fold decreases, respectively. The relationship between meteorological conditions and mosquito density, according to various variables, was not significant different. The Chaoyang virus was found in Aedes vexans and Culex pipiens collected at the cowshed in 2016 and 2018, respectively. Based on the results of this study, it is considered that continuous surveillance of mosquitoes should be performed for controlling mosquito populations and mediating diseases spread by this vector.

• Journal of the Korean Geosynthetics Society
• /
• v.21 no.4
• /
• pp.55-67
• /
• 2022

In this paper, fundamentals and recent development of the interferometric synthetic aperture radar, known as InSAR, technique for measuring ground deformation through satellite image analysis are presented together with case histories illustrating its applicability to urban ground deformation monitoring. A study area in Korea was selected and processed based on the muti-temporal time series InSAR analysis, namely SBAS (Small Baseline Subset)-InSAR and PS (Persistent Scatterers)-InSAR using Sentinel-1A SAR images acquired from the year 2014 onward available from European Space Agency Copernicus Program. The ground settlement of the study area for the temporal window of 2014-2022 was evaluated from the viewpoint of the applicability of the InSAR technique for urban infrastructure settlement monitoring. The results indicated that the InSAR technique can reasonably monitor long-term settlement of the study area in millimetric scale, and that the time series InSAR technique can effectively measure ground settlement that occurs over a long period of time as the SAR satellite provides images of the Korean Peninsula at regular time intervals while orbiting the earth. It is expected that the InSAR technique based on higher resolution SAR images with small temporal baseline can be a viable alternative to the traditional ground borne monitoring method for ground deformation monitoring in the 4^th industrial era.

• Journal of Life Science
• /
• v.20 no.3
• /
• pp.365-373
• /
• 2010

To monitor newly emerged influenza virus variants and to investigate the prevalence pattern, our laboratory performed isolation of the viruses from surveillance sentinel hospitals. In the present study, we analysed influenza A/H1N1, A/H3N2, B viruses isolated in Busan during the 2006/07 and 2007/08 seasons by sequence analysis of the hemagglutinin (HA1 subunit) and neuraminidase (NA) genes. The isolates studied here were selected by the stratified random sample method from a total of 277 isolates, in which 15 were A/H1N1, 16 were A/H3N2 and 29 were B. Based on the phylogenetic tree, the HA1 gene showed that A/H1N1 isolates had a 96.7% to 97.7% homology with the A/Brisbane/59/2007, A/H3N2 isolates had a 98.4% to 99.7% homology with the A/Brisbane/10/2007, and B isolates had a 96.5% to 99.7% homology with the B/Florida/4/2006(Yamagata lineage), which are all the vaccine strains for the Northern Hemisphere in 2008~2009 season. In the case of the NA gene, A/H1N1 isolates had 97.8% to 98.5% homologies, A/H3N2 isolates had 98.9% to 99.4% homologies, and B isolates had 98.9% to 100% homologies with each vaccine strain in the 2008~2009 season, respectively. Characterization of the hemagglutinin gene revealed that amino acids at the receptor-binding site and N-linked glycosylation site were highly conserved. These results provide useful information for the control of influenza viruses in Busan and for a better understanding of vaccine strain selection.

• Pediatric Gastroenterology, Hepatology & Nutrition
• /
• v.8 no.1
• /
• pp.31-40
• /
• 2005

Purpose: This study aimed to provide, as a basic material, the experiences of endoscopy in diagnosis and treatment of tumorous conditions in the upper gastrointestinal tract in children. Methods: The objects were 26 patients diagnosed as having tumorous conditions in the upper gastrointestinal tract among 1,283 patients who underwent upper gastrointestinal endoscopic examination at the Department of Pediatrics, Pusan National University Hospital, from January 1994 to July 2004 retrospectively. The characteristics of patients, the chief complaints for endoscopic examination, the sorts of tumors diagnosed, the endoscopic findings of tumors, and the treatment of tumors were analysed. Results: 1) Eleven male and fifteen female were included, whose mean age was $6.93{\pm}4.02years$. 2) The chief complaints for endoscopic examination were abdominal pain (80.7%), vomiting or nausea (30.8%), and gastrointestinal beeding (30.7%) in order. 3) Six cases of ectopic pancreas, five cases of sentinel polyp, three cases of papilloma and vallecular cyst, two cases of Brunner's gland hyperplasia and gastric submucosal tumor, one case of gastrointestinal stromal tumor, duodenal intramural hematoma, T cell lymphoma, lipoma, and Peutz-Jeghers syndrome were diagnosed by endoscopy with or without biopsy. 4) The location of tumors was in the pharynx (19.2%), esophagus (7.7%), gastro-esophageal junction (23.0%), stomach (30.7%) and duodeneum (26.9%). 5) The size of tumors was less than 10 mm in 53.8%, 10~20 mm in 26.9%, more than 20 mm 19.2%. 6) Treatments for tumors included resection by laser, surgical resection, endoscopic polypectomy with a forcep or snare, and observation 7) There was no significant complication. Conclusion: Various and not a few tumors were found in the upper gastrointestinal tract. The endoscopy was accurate, effective, and safe means for diagnosis and treatment of those lesions in children.