• Journal of Korean Society of Coastal and Ocean Engineers
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• v.35 no.6
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• pp.146-154
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• 2023

In this study, the peak wave period T_p and mean wave period T₀₂ and T_{m-1, 0}, which are major parameters for classifying ocean characteristics, were calculated using water surface elevation data observed from the second west coast oceanographic and meteorological observation tower. In addition, the ratio of abnormal data, correlation analysis, and optimal probability density function were estimated. In the case of T_p among the calculated representative periods, the proportion of abnormal data was 5.73% and 0.67% at each point, and T₀₂ was 4.35% and 0.01%. T_{m-1, 0} was found to be 2.82% and 0.03%. Meanwhile, as a result of analyzing the relationship between T₀₂ and T_p, the relationship was calculated to be 0.53 and 0.63 for each point. The relationship between T_{m-1, 0} and T_p was 1.15 and 1.32, respectively, and T₀₂, T_{m-1, 0} was 1.18 and 1.22. As a result of estimating the optimal probability density function of the calculated representative period, T_p followed the 'Log-normal' and 'Normal' distributions at each point, and T₀₂ was 'Gamma', 'Normal' distribution and T_{m-1, 0} showed that 'Log-normal' and 'Normal' distribution were dominant, respectively. It is decided that these results can be used as basic data for wave analysis conducted on the west coast.

• Korean Journal of Ecology and Environment
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• v.56 no.3
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• pp.207-217
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• 2023

This study was conducted to investigate the current status of seagrass species in the Nakdong River estuary from May to June 2023. To survey the seagrass habitat area, the Nakdong River estuary was divided into seven zones. Aerial photography using drones was conducted to find seagrass areas, GPS tracking was carried out on foot in the intertidal zone and by boat and SCUBA diving in the subtidal zone. To analyze the seagrass status, we measured the morphological characteristics, shoot density, and biomass of representative seagrass species in each zone. Four seagrass species were found in this area: Zostera japonica, Z. marina, Ruppia maritima, and Phyllospadix japonicus. The distribution areas of each species was 338.2 ha, 92.9 ha, 0.9 ha, and 1.4 ha, respectively, with a total area of 432.5 ha. Z. japonica was widely distributed in most of the tidal flats and mudflats of the Nakdong River estuary, while Z. marina was restricted to Nulcha-do, Jinu-do, and Dadae-dong. R. maritima occurred within the habitat of Z. japonica in Eulsukdo and Myeongji mudflats, and P. japonicus inhabited rocky areas in Dadae-dong. The shoot density of each species was 4,575.8±338.3 shoots m^-2, 244.8±12.0 shoots m^-2, 11,302.1±290.0 shoots m^-2, and 2862.5±153.5 shoots m^-2, respectively. The biomass of each species was 239.7±18.5 gDW m^-2, 362.3±20.5 gDW m^-2, 33.3±1.2 gDW m^-2, and 1,290.0±37.0 gDW m^-2, respectively. The results of this study revealed that Z. japonica was dominant in the Nakdong River estuary. In particular, Z. japonica habitats of Eulsukdo, Daema-deung, and Myeongji mudflats were identified as the largest in Korea. The Nakdong River estuary is an important site of ecological, environmental, and economic value, and will require continuous investigation and management of the native seagrasses.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.13 no.1
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• pp.27-41
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• 2008

Distribution characteristics of phytoplankton community were investigated by HPLC and flow cytometry in Jeju Strait and the Northern East China Sea (NECS) in May 2004, in order to understand the relationship between physical environmental factors and distribution pattern of phytoplankton communities. Based on temperature and salinity data, three distinct water masses were identified; warm and saline Tsushima Warm Current (TWC), which is flowing from northwest of Jeju Island, warm and low saline water at the center of Jeju Strait, which is originated from China Coastal Water (CCW) and relatively cold and high saline water originated from Yellow Sea at the bottom of the Jeju Strait. At Jeju Strait, less saline water (<33 psu) of 15 km width occupied surface layer up to 20 m which located at 20 km offshore and strong thermal front between warm and saline water and cold and less saline water was found in the middle of the Jeju Strait. Vertical transect of temperature and salinity at the NECS also showed that low saline (<33 psu) water occupied the upper 20 m layer and cold and saline water was present at the eastern part. Chl a was measured as $0.06{\sim}3.07\;{\mu}g/L$. Spring bloom of phytoplankton was recognized by the high concentrations of Chl a at the low saline water masses influenced by the CCW and subsurface chlorophyll maximum layer appeared between $20{\sim}30\;m$ depth, which was at thermocline depth or below. Abundances of Synechococcus and picoeukaryote were $0.2{\sim}9.5{\times}10^4\;cells/mL$ and $0.43{\sim}4.3{\times}10^4\;cells/mL$, respectively. Dinoflagellate, diatom and prymnesiophyte were major groups and minor groups were chlorophyte+prasinophyte, chrysophyte, cryptophyte and cyanophyte. Especially high abundance of dinoflagellate was identified by high concentration (>1\;{\mu}g/L$) of peridinin at the bottom of the thermocline, which showed an outbreak of red tide by high density of dinoflagellates. Abundances of picoeukaryote in Jeju Strait were about $5{\sim}10$ times higher than abundance measured in Kuroshio water and showed a good correlation with Chl b (Pras+Viola), which implies the most of population of picoeukaryote was composed of prasinophytes. Prochlorococcus was not detected at all, which suggests that Kuroshio Current did not directly influenced on the study area. Based on the strong negative correlations between biomass of phytoplankton (Chl a) and temperature+salinity, the primary production and biomass of phytoplankton in the study area were controlled by the nutrients supply from CCW.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.18 no.2
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• pp.149-156
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• 1985

Distribution of lipid components in the tissue of meat, skin and viscera from carp(Cyprynus carpio) was analyzed using the techniques of column chromatography, thin layer chromatography and gas liquid chromatography according to the previous report(Choi, et al., 1984). Lipid content was varied by the portion such as $3.88\%$ in meat (free lipid, $2.47\%$ ; bound lipid, $1.41\%$), $8.02\%$ in skin(free lipid, $5.65\%$ ; bound lipid, $2.37\%$) and $6.18\%$ in viscera (free lipid, $3.54\%$ ; bound lipid, $2.64\%$). In the all portions of the body, free lipid was composed of $68\%\;to\;92\%$ in neutral lipid, $3\%\;to\;6\%$ in glycolipid and $4\%\;to\;18\%$ in phospholipid whereas bound lipid was composed of $8\%\;to\;20\%$ in neutral lipid, $2\%\;to\;7\%$ in glycolipid and $47\%\;to\;62\%$ in phospholipid. The free lipids of the tissues on the each portion were mostly represented by triglycerides and some diglycerides, but free lipids in viscera contained considerable amounts of free fatty acids. The bound lipids, on the other hand, commonly comprised appreciable amounts of esterified sterol and hydrocarbon, and triglycerides. The phospholipid was mainly consisted of phosphatidyl choline, phosphatidyl ethanolamine and phosphatidyl serine in the both free and bound lipids, and much more phosphatidyl choline in the bound lipid. The predominant fatty acids of free and bound lipids were $C_{16:0},\;C_{18:0},\;C_{20:4},\;C_{22:6}\;and\;C_{18:2}$ acids in polar lipids, and $C_{16:0},\;C_{16:1},\;C_{18:0},\;C_{18:1}\;and\;C_{18:2}$ acids in non-polar lipids, whereas those of neutral lipids were $C_{14:0}(2.54{\sim}6.98\%),\;C_{16:0}(11.20{\sim}21.13\%)$ and $C_{18:0}(1.58{\sim}12.76\%)$ of saturated acids, $C_{16:1}(7.06{\sim}20.70\%),\;C_{18:1}(21.68{\sim}30.50\%)$ and $C_{20:1}(1.76{\sim}6.27\%)$ of monoenoic acids, and $C_{18:2}(4.50{\sim}6.89\%),\;C_{20:4}(1.52{\sim}4.29\%)$ and $C_{22:6}(0.73{\sim}6.62\%)$, respectively. In conclusion, the fatty acid compositions revealed apparent differences between the free lipid and bound lipids in the tissues of body.

• Progress in Medical Physics
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• v.25 no.2
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• pp.100-109
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• 2014

In stereotactic body radiotherapy (SBRT), the accurate location of treatment sites should be guaranteed from the respiratory motions of patients. Lots of studies on this topic have been conducted. In this letter, a new verification method simulating the real respiratory motion of heterogenous treatment regions was proposed to investigate the accuracy of lung SBRT for Volumetric Modulated Arc Therapy. Based on the CT images of lung cancer patients, lung phantoms were fabricated to equip in $QUASAR^{TM}$ respiratory moving phantom using 3D printer. The phantom was bisected in order to measure 2D dose distributions by the insertion of EBT3 film. To ensure the dose calculation accuracy in heterogeneous condition, The homogeneous plastic phantom were also utilized. Two dose algorithms; Analytical Anisotropic Algorithm (AAA) and AcurosXB (AXB) were applied in plan dose calculation processes. In order to evaluate the accuracy of treatments under respiratory motion, we analyzed the gamma index between the plan dose and film dose measured under various moving conditions; static and moving target with or without gating. The CT number of GTV region was 78 HU for real patient and 92 HU for the homemade lung phantom. The gamma pass rates with 3%/3 mm criteria between the plan dose calculated by AAA algorithm and the film doses measured in heterogeneous lung phantom under gated and no gated beam delivery with respiratory motion were 88% and 78%. In static case, 95% of gamma pass rate was presented. In the all cases of homogeneous phantom, the gamma pass rates were more than 99%. Applied AcurosXB algorithm, for heterogeneous phantom, more than 98% and for homogeneous phantom, more than 99% of gamma pass rates were achieved. Since the respiratory amplitude was relatively small and the breath pattern had the longer exhale phase than inhale, the gamma pass rates in 3%/3 mm criteria didn't make any significant difference for various motion conditions. In this study, the new phantom model of 4D dose distribution verification using patient-specific lung phantoms moving in real breathing patterns was successfully implemented. It was also evaluated that the model provides the capability to verify dose distributions delivered in the more realistic condition and also the accuracy of dose calculation.

• Progress in Medical Physics
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• v.22 no.4
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• pp.190-197
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• 2011

Currently, the dose distribution calculation used by commercial treatment planning systems (TPSs) for high-dose rate (HDR) brachytherapy is derived from point and line source approximation method recommended by AAPM Task Group 43 (TG-43). However, the study of Monte Carlo (MC) simulation is required in order to assess the accuracy of dose calculation around three-dimensional Ir-192 source. In this study, geometry factor was calculated using segmented sources integration method by dividing microSelectron HDR Ir-192 source into smaller parts. The Monte Carlo code (MCNPX 2.5.0) was used to calculate the dose rate $\dot{D}(r,\theta)$ at a point ($r,\theta$) away from a HDR Ir-192 source in spherical water phantom with 30 cm diameter. Finally, anisotropy function and radial dose function were calculated from obtained results. The obtained geometry factor was compared with that calculated from line source approximation. Similarly, obtained anisotropy function and radial dose function were compared with those derived from MCPT results by Williamson. The geometry factor calculated from segmented sources integration method and line source approximation was within 0.2% for $r{\geq}0.5$ cm and 1.33% for r=0.1 cm, respectively. The relative-root mean square error (R-RMSE) of anisotropy function obtained by this study and Williamson was 2.33% for r=0.25 cm and within 1% for r>0.5 cm, respectively. The R-RMSE of radial dose function was 0.46% at radial distance from 0.1 to 14.0 cm. The geometry factor acquired from segmented sources integration method and line source approximation was in good agreement for $r{\geq}0.1$ cm. However, application of segmented sources integration method seems to be valid, since this method using three-dimensional Ir-192 source provides more realistic geometry factor. The anisotropy function and radial dose function estimated from MCNPX in this study and MCPT by Williamson are in good agreement within uncertainty of Monte Carlo codes except at radial distance of r=0.25 cm. It is expected that Monte Carlo code used in this study could be applied to other sources utilized for brachytherapy.

• Korean journal of applied entomology
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• v.47 no.4
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• pp.337-343
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• 2008

This study was conducted to investigate the distribution pattern, ecological characteristics and life cycle of the Black Soldier Fly (Hermetia illucens, BSF). The BSF was widely distributed throughout Korea. The insect was mainly found in the vicinity of and in cattle sheds, manure sheds, living waste dump grounds, and food waste dump grounds. Developmental characteristics of the BSF are as follows: the egg was long oval shaped of 887 ${\mu}m$ in the major axis and 190 ${\mu}m$ in the minor axis; it weighed 24 ${\mu}g$. Female oviposited ca. 1,000 eggs on average; eggs hatched in 81 hours under laboratory condition ($27^{\circ}C$, 60% R.H.). The duration of the larval stage was approximately $15{\sim}20$ days. The size of the last instar larvae was 21 mm. The cuticle of the pupae gradually acquired red-brown color and the size of them was 19 mm. The pupal stage was shorter for females (16 days) than males (15 days). Adults were sized about $13{\sim}20$ mm long and black-colored. The life span of adult insects was $5{\sim}8$ days for the first generation (June${\sim}$July), $7{\sim}10$ days for the second generation (Aug.${\sim}$Sept.), and $13{\sim}18$ days for the third generation (Sept.${\sim}$Oct.). Mating started on the next day of emergence and actively occurred at the third day after emergence. Mating mostly occurred between 10:00 and 16:00 during which light intensity is highest. Egg-laying started on the third day and was most frequent from the fourth to the sixth day after emergence. Similar to mating time, females oviposited mostly between 10:00 and 16:00.

• Tuberculosis and Respiratory Diseases
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• v.62 no.3
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• pp.203-210
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• 2007

Background: The incidence of adenocarcinoma of the lung has been increasing worldwide, and it has been generally been accepted to be relatively unrelated to smoking with a female preponderance. The aim of this study was to examine the gender-related pathological and survival differences in patients with an adenocarcinoma of the lung. Material and Method: A retrospective review of the clinical information of patients diagnosed with an adenocarcinoma of the lung at Kosin Medical Center from January 1999 to September 2005 was performed. The patient's demographics (age, gender), smoking history, stage, serum tumor marker, pathology classification, EGFR mutation, K-ras mutation, treatment methods, and survival time were analyzed. Result: Of the 438 patients, 179 (40.9%) were female. The median age at the diagnosis was 58 years for females and 59 years for males. However, 25.8% of women and only 17.7% of men were under 50 years of age (p=0.02). The distribution of the disease stage was similar in both men and women. The bronchioloalveolar carcinoma component was diagnosed more often in women (11.2%) than in men (5.0%). The overall survival rate was higher in women than in men (p=0.01), and women had a superior therapeutic response to a combined treatment of surgery and chemotherapy. Conclusion: This study showed significant genders differences in terms of the smoking history, bronchioloalveolar carcinoma component, overall survival, and survival after combined treatment of surgery and chemotherapy. Therefore, gender differences should be considered when diagnosing and treating adenocarcinomas of the lung.

• Clinics in Shoulder and Elbow
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• v.11 no.2
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• pp.104-111
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• 2008

Purpose: The aim of this study is to analyze the clinical results of using the technique of rotator cuff repair without parting the biceps long head from the glenoid for large or massive tear of the rotator cuff. Material and Methods: Form January 2005 to January 2007, we performed the arthroscopic biceps repair with incorporating suture to the rotator cuff for 21 patients with large or massive rotator cuff tear. The mean follow up period was 23 months (range: 6-48months). The number of males and females was 9 and 13, respectively. The age distribution ranged from 47 to 73 years with a mean age of 60.3 years. We compared the preoperative score with the postoperative scores using the University of California Los Angeles (UCLA) score, the shoulder index of the American Shoulder and Elbow Surgeons (ASES) and a simple shoulder test (SST). Results: The improvement in the VAS, ASES and the UCLA and SST scores was statistically significant at the final follow up (average follow-up 23 months) (p>0.05). Two of nine cases were found to have partial tear with continuity but seven cases were found to have complete tear according to the ultrasonography and MRI. Conclusion: The technique of rotator cuff repair without parting the biceps long head from the glenoid for large or massive tear of the rotator cuff is considered to be recommendable.

• Korean Journal of Remote Sensing
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• v.33 no.6_2
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• pp.1119-1137
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• 2017

This study assessed the water provisioning and climate mitigation ecosystem services of the urban forest in Seoul and Gyeonggi-do. The ecosystem service assessment is conducted based on natural function, natural function and population, and natural function and the beneficiary of the ecosystem service. Then, the impact of climate change on ecosystem services is analyzed to figure out the sensitivity of the impact on the beneficiary when the natural function of forest destroys under climate change. Gyeonggi-do has higher function-based water provisioning ecosystem service than Seoul. And population-based water provisioning ecosystem service appears to be higher in the densely populated area. On the other hand, beneficiary-based water provisioning ecosystem service by applying both natural water supply function and beneficiary distribution appears different with the result of population-based water provisioning service assessment. In other words, regions with high beneficiary population show higher ecosystem service than those with a low beneficiary population even though they have the same water storage function. In addition, climate change has a negative impact on the water provisioning ecosystem service. Under climate change, water provisioning service is expected to decrease by 26%. For climate mitigation service, regions close to the forest seem to have a low temperature, which indicates their high climate mitigation service. The center of the city with high beneficiary population shows high beneficiary-based ecosystem service. The climate change impacts the forest growth to decrease which affect the beneficiary-based climate mitigation ecosystem service to decrease by 33%. From this study, we conclude that beneficiary-based function and ecosystem service assessment is needed as well as the supply-based classification of forest function suggested by Korea Forest Service. In addition, we suggest that not only supply-based function classification and ecosystem service assessment but also beneficiary-based function classification and ecosystem service assessment is needed for managing the urban forest, which has been destroyed by climate change. This will contribute to revaluing cases where a forest with low natural function but high beneficiary-based ecosystem service, which is not considered under the current forest function-based assessment system. Moreover, this could assist in developing a suitable management plan for the urban forest.