• Journal of Korea Water Resources Association
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• v.56 no.12
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• pp.919-928
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• 2023

Rainfall characteristics in Korea are concentrated during the summer flood season. In particular, when a large amount of turbid water flows into the dam due to the increasing trend of concentrated rainfall due to abnormal rainfall and abnormal weather conditions, prolonged turbid water phenomenon occurs due to the overturning phenomenon. Much research is being conducted on turbid water prediction to solve these problems. To predict turbid water, turbid water data from the upstream inflow is required, but spatial and temporal data resolution is currently insufficient. To improve temporal resolution, the development of the Turbidity-SS conversion equation is necessary, and to improve spatial resolution, multi-item water quality measurement instrument (YSI), Laser In-Situ Scattering and Transmissometry (LISST), and hyperspectral sensors are needed. Sensor-based measurement can improve the spatial resolution of turbid water by measuring line and surface unit data. In addition, in the case of LISST-200X, it is possible to collect data on particle size, etc., so it can be used in the Turbidity-SS conversion equation for fraction (Clay: Silt: Sand). In addition, among recent remote sensing methods, the spatial distribution of turbid water can be presented when using UAVs with higher spatial and temporal resolutions than other payloads and hyperspectral sensors with high spectral and radiometric resolutions. Therefore, in this study, the Turbidity-SS conversion equation was calculated according to the fraction through laboratory analysis using LISST-200X and YSI-EXO, and sensor-based field measurements including UAV (Matrice 600) and hyperspectral sensor (microHSI 410 SHARK) were used. Through this, the spatial distribution of turbidity and suspended sediment concentration, and the turbidity calculated using the Turbidity-SS conversion equation based on the measured suspended sediment concentration, was presented. Through this, we attempted to review the applicability of the Turbidity-SS conversion equation and understand the current status of turbid water occurrence.

• Journal of the East Asian Society of Dietary Life
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• v.1 no.3
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• pp.259-276
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• 1991

The review of side dishes, oereal dishes and seasonings of the banquet on the 24th year of King Kojong in Chosun Dynasty were summarized as follows: 1. Ten kinds of soups(=Tang), that is Yyolguja Tang$.$Guja Tang$.$Keumjung Tang$.$Whanja Tang$.$Jap Tang$.$Gol Tang$.$Seunggiwa Tang$.$Jeopo Tang$.$Haesam Tang$.$Yang Tang were served. The most frequently served soup among them was Yyolguja Tang. 2. Various kinds of dried meat/fish were piled up most highly among dishes. Sliced beef and minced beef among dried meats, white cud$.$yellow cud$.$flatfish$.$skate$.$shark$.$octopus$.$dried abalone$.$cuttle fish$.$dried scallop were piled up together. 3. Sliced of boiled beef/pork and gelatined knuckles were assorted. Boiled meat which was made of beef, pork, lamb, liver, stomach, brisket and plat flank of caw was chiefly used for boiled beef, hams for boiled pork, mediumsized lamb for boiled lamb. And the legs and stomach of caw, old chicken, mullet were used for gelatined knuckle. 4. Three kinds of pan-frying dishes that was stomach and liver of caw, and mullet were usually piled up, If one kind in one dish, sea cucumber and mullet were used respectively. 5. Boiled abalone was dried abalone with soaked, sliced and boiled down in soysauce. 6. Roasted dish was usually made of assorted food stuffs. Sometimes chicken an pheasant was used for roasted dish. 7. Steamed dish was like this : assorted beef, fresh abalone, sea cucumber, mullet, young pork, chicken, dried abalone. 8. Raw dish was made of intestine of caw, fresh abalone and mullet. 9. Poached egg was serving decorated with red pepper, pine-nut and green onion. 10. Seasoned green-been-jelly was served only one time. 11. Radish kimchi was served only one time. 12. Chief foods were nuddle and stuffed bun. 13. Served seasings were honey, mustard, soysauce with vinegar, salt. Review from banquet menu, 34 kinds of side dishes were served : 10 kinds of soup, dried fish/meat, boiled beef, boiled pork, gelatined knuckle, 5 kinds of panfrying, boiled-down-abalone in soysauce, 3 kinds of roast, 5 kinds of steamed, 3 kinds of raw dishes, pouched egg, green-bean-jelly, kimchi. 4 kinds of chief foods were served : nuddle, dry nuddle, 2 kinds of dumping.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.29 no.7
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• pp.477-483
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• 2018

A transparent antenna designed on the front glass of an automobile operating in the FM broadcast band(88~108 MHz) is proposed. A transparent antenna designed on the front glass of the automobile to avoid space limitation is typically positioned as a roof-mounted shark-fin antenna. An antenna designed on the front glass can reasonably solve the problems of low reception sensitivity and radiated interference from antennas for other service bands. The front glass has a unique closed-line structure, and this structure causes the surface current to flow to the front glass's surroundings; thus, the first resonance is caused before the broadcast band. Through the use of this closed-line structure, the surface current distribution is controlled, and an antenna for which the first resonance is operating in the frequency-modulated(FM) band can be designed. Moreover, the use of a micro-metal-mesh film that is a transparent electrode, suitable for designing a radio frequency device, enables the antenna to minimize visual perception through its transparency. The measured reflection coefficient($S_{11}$) of the antenna is less than -6 dB, and the average peak gain is -0.9 dB in the FM band. Experiments show that the transparent antenna on the front glass offers both the space and design freedom required to develop future automotive antennas.

• The Journal of the Korea Contents Association
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• v.20 no.5
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• pp.222-235
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• 2020

This study examines the poverty progress and its factors which drove the lives of the middle-aged men in Chokbang area. The observed examples are the retired government officials and the self-employed who have been classified as the ones in the economically-middle class but currently as the welfare recipients. According to the results of in-depth interview and observation, the poverty of the observed has undergone the progress of trigger, worsening, breakup, desperation and stabilizing stages. The poverty factors found in this study could be categorized into two factors; circumstantial factors(bankruptcy after IMF, debt guarantee for relatives) and inner factors(the participants' behavior and characteristics). The circumstantial factors worked mainly in the trigger stage and the inner factors contributed to worsening economic crisis and facilitating the progress. According to the result, this study suggests not only individual-scale measures such as encouragement of familial bond or medical treatment of the alcoholism but also social measures including proper regulation of shark loan and opportunity supply to exit from poverty.

• Tuberculosis and Respiratory Diseases
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• v.65 no.3
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• pp.239-242
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• 2008

Exogenous lipoid pneumonia is an uncommon disease that's caused by aspirating lipid formulations. Squalene, obtained from shark liver oil, is one of the causative agent and this is commonly used by some Koreans as a health promoting medication. We report here on a case of exogenous lipoid pneumonia that developed after ingestion of squalene capsules. The case showed milky BAL fluid and multiple pulmonary consolidations.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.37 no.6
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• pp.445-454
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• 2004

A search for contraction and relaxation responses on the smooth muscles, antimicrobial and antioxidant activity in different body parts of 4 freshwater fish and 4 marine fish were conducted. The four freshwater fish studied were Sarotherodon niloticus (tilapia), Channa arus (snake head), Cyprinus carpio (Israel carp) and Siluru osotus (catfish), and the four marine fish were Scyliorhinus torazame (tiger shark), Ateiepus japonicus (tadpole fish), Mugil cephalus (gray mullet) and Thamnaconus modestus (file fish). Frozen samples were extracted with distilled water containing $1{\%}$ acetic acid. Antimicrobial activity against Bacillus subtilis and Eschrrichia coli was detected in extracts from several tissues in all species tested. Relatively high antimicrobial activity could also be detected in the bile extracts from C. carpio, M. cephalus, and T. modestus. Contraction and relaxation responses on smooth muscles could be detected in all species tested, especially in the intestine extracts. Antioxidant activity was also detected in extracts from several tissues in all species tested, while in the extracts from S. osotus, excluding livers and spleens, no antioxidant activity was detected. Results from this study suggest that fish are a potential source for the discovery of novel bioactive materials.

• Korean Journal of Optics and Photonics
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• v.17 no.5
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• pp.383-390
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• 2006

The SharkHartmann wavefront sensors are the most popular devices to measure wavefront in the field of adaptive optics. The Shack-Hartmann sensors measure the centroids of spot irradiance distribution formed by each corresponding micro-lens. The centroids are linearly proportional to the local mean slopes of the wavefront defined within the corresponding sub-aperture. The wavefront is then reconstructed from the evaluated local mean slopes. The uncertainty of the Shack-Hartmann sensor is caused by various factors including the detector noise, the limited size of the detector, the magnitude and profile of spot irradiance distribution, etc. This paper investigates the noise propagation in two major centroid evaluation algorithms through computer simulation; 1st order moments of the irradiance algorithms i.e. center of gravity algorithm, and correlation algorithm. First, the center of gravity algorithm is shown to have relatively large dependence on the magnitudes of noises and the shape & size of irradiance sidelobes, whose effects are also shown to be minimized by optimal thresholding. Second, the correlation algorithm is shown to be robust over those effects, while its measurement accuracy is vulnerable to the size variation of the reference spot. The investigation is finally confirmed by experimental measurements of defocus wavefront aberrations using a Shack-Hartmann sensor using those two algorithms.

• Journal of Marine Life Science
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• v.1 no.1
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• pp.8-17
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• 2016

The family Pristiophoridae belonging to the order Pristiophoriformes consists of about 8 species and 2 genera in the world. Among them, only one species (Pristiophorus japonicus) is distributed in northwestern Pacific. The family is characterized by having an elongated and flattened rostrum with laterally projecting a low of sharp teeth. In order to clarify variability of local populations of P. japonicus, we investigated 16 individuals collected from four locations (Korea, n=6; Miyagi, n=1; Kochi Pref., n=1; Okinawa, n=8) for morphological and molecular analyses. Morphological analysis showed that there may exist three morphotypes, of which A morphotype (Korea, Miyagi, Kochi Pref.) has a short snout (26.8% of TL), being most similar to syntypes of P. japonicus. On the other hand, B morphotype (Okinawa) has a long (31.7% of TL) and wider snout (snout width at nostrils 5.2 times pre-oral length) and, C morphotype (Okinawa) has a long (31.7% of TL) and narrower snout (6.3 times). Molecular analysis using mitochondrial DNA cytochrome b DNA sequences (386 base pairs) showed that the K2P distance between A and C morphotypes were 2.1~2.7%, but those within A morphotype were 0.0~0.5%. We identified A morphotype as P. japonicus, and designated B and C morphotypes as Pristiophorus sp. 1 and Pristiophorus sp. 2, respectively. Further studies are required to elucidate the taxonomic status of two morphotypes of the sawshark in Okinawa.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.27 no.3
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• pp.247-258
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• 1994

A total of 31 commercial dried marine food products, consisting of 14 fishes, 2 shellfishes and 2 seaweeds species were analyzed for their contents of precusors of N-nitrosamine such as dimethylamine(DMA), trimethylamine(TMA), trimethylamine oxide (TMAO), betaine and nitrate and nitrite nitrogen as factors of N-nitrosamine formation. Carcinogenic N-nitrosamines were extracted by a steam distillation apparatus and were analyzed for their components using a gas chromatography-thermal energy analyzer. N-nitrosodimethylamine(NDMA) was confirmed by a gas chromatography-mass spectrometry. The contents of betaine nitrogen in samples were in the range of $5.2{\sim}373.8mg\%$ and were significantly higher than tertiary amines such as TMA and TMAO. DMA nitrogen in those samples was in the range of trace-31.2ppm and was high, in the dried shark(31.2ppm), alaska pollack($22.9{\sim}24.3ppm$) and octopus($17.9{\sim}18.4ppm$). In dried laver and sea mustard, however, amines were not detected at all. The levels of nitrate nitrogen in the dried marine samples ranged from zero to 16.8ppm and were high in the dried stingray(16.8ppm), alaska pollack(16.3ppm) and squid($2.2{\sim}12.4ppm$), but were less than 1.0 ppm in other samples. The levels of nitrite nitrogen were lower than those of nitrate nitrogen and it was not detected in dried sea cucumber, laver and sea mustard. Twenty eight of 31 samples contained NDMA($range=1.2{\sim}86.0ppb$), which was the only volatile N-nitroso compound found. The NDMA levels of dried stingray($2.8{\sim}86.0ppb$), alaska pollack($8.2{\sim}55.5ppb$), squid($3.3{\sim}53.2ppb$), yellow corvenia($45.9ppb$) and plain dried shrimp($15.4{\sim}17.9ppb$) were high. However, it was not detected in dried sea cucumber, laver and sea mustard. Samples, containing high levels of NDMA, also contained high nitrate and nitrite nitrogen. From above results, it can be concluded that nitrate and nitrite were major factors for the formation of NDMA in dried marine food products.

• Korean Journal of Ichthyology
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• v.28 no.2
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• pp.125-133
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• 2016

Sharks (Selachii) comprising about 510 valid species worldwide. Forty-three shark species belonging to 30 genera, 19 families and 8 orders have been found in Korean coastal waters, and all these are registered at the IUCN Red List as followings: endangered (EN) 1 species (2.3%) (vs. worldwide 15 spp., 3.2%), vulnerable (VU) 11 spp. (25.6%) (vs. 48 spp., 10.3%), near threatened (NT) 10 spp. (23.3%) (vs. 67 spp., 14.4%), least concern (LC) 9 spp. (20.9%) (vs. 115 spp., 24.7%), data deficient (DD) 12 spp. (27.9%) (vs. 209 spp., 44.9%), and critically endangered (CR) absent (vs. 11 spp., 2.4%). Twelve species among 43 sharks distributing in Korean waters are assessed as Threatened in the IUCN Red List categories and criteria as followings: Sphyrna lewini (EN, A2bd+4bd), Rhincodon typus (VU, A2bd+3d), Cetorhinus maximus (VU, A2ad+3d), Carcharodon carcharias (VU, A2cd+3cd), Isurus oxyrinchus (VU, A2abd+3bd+4abd), Alopias pelagicus (VU, A2d+4d), A. vulpinus (VU, A2bd+3bd+4bd), Carcharhinus plumbeus (VU, A2bd+4bd), S. zygaena (VU, A2bd+3bd+4bd), Squalus suckleyi (VU, A2bd+3bd+4bd), Squatina japonica (VU, A2d+4d), and S. nebulosa (VU, A2d+4d). Eighteen chondrichthyan species are registered in the list of the CITES Appendices, among them five sharks are distributing in Korean waters as Appendix II, i.e., R. typus, C. maximus, C. carcharias, S. lewini and S. zygaena. The scientific name of "Gobsangeo" has been changed from Squalus acanthias of the North Pacific to S. suckleyi, and "Mojorisangeo" from S. megalops of the Northwest Pacific to brevirostris.