• KSCE Journal of Civil and Environmental Engineering Research
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• v.38 no.2
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• pp.357-367
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• 2018

Recent earthquakes in Gyeongju and Pohang have raised interest in liquefaction in South Korea. Liquefaction, which is a phenomenon that excessive pore pressure is generated and the shear strength of soil is decreased by repeated loads such as earthquakes, causes severe problems such as ground subsidence and overturning of structures. Therefore, it is necessary to identify and prepare for the possibility of liquefaction in advance. In general, the possibility of liquefaction is quantitatively assessed using the Liquefaction Potential Index (LPI), but it takes a lot of time and effort for performing site response analysis which is essential for the liquefaction evaluation. In this study, a simple method to evaluate the liquefaction potential without executing the site response analysis in a downtown area with a lot of borehole data was proposed. In this simple method, the correlation between the average shear wave velocity of the target location ground and the LPI divided by thickness of liquefiable layer was established. And the applicable correlation equation for various rock outcrop accelerations were derived. Using the 104 boreholes information in Seoul, the correlation equation between LPI and the shear wave velocity (ground water level: 0m, 1m, 2m, 3m) is obtained and the possibility of liquefaction occurrence in Seoul and Gyeongju is evaluated. The applicability of the proposed simple method was verified by comparing the LPI values calculated from the correlation equation and the LPI values derived using the existing site response analysis. Finally, the distribution map of LPI calculated from the correlation was drawn using Kriging, a geostatistical technique.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.14
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• pp.53-64
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• 1973

The studies reported herein were conducted to investigate the effect of thermal conditions in double-cropping of rice. The accumulated daily mean and minimum air temperatures, for the period of the last 30 years, were examined at the 10 different meteorogical stations which are located in the southern part of Korea. The results obtained could be summarized as follows: 1. The first cropping. a. It seemed to be free from any frost-damage of rice at the seeding stage at Yeosu, Pusan and Cheju. However, it was found that there were some dangers of frost damage for about 30 to 40 day at Iri, Chonju and Kwangju, for 18 to 28 days at Daeku and Ulsan, and for 4 to 14 days at Mokpo and Pohang, respectively. b. The early critical transplanting date seemed to be from middle to late-April in the first cropping. As compared with the ordinary lowland seedlings, the semi-protected and upland ones could be planted 5 and 10 days earlier, respectively. c. The early critical heading date was about late-June and there were some low-temperature damages for 8 to 25 days at young-ear formation stage of rice plant, depending upon location. d. The early critical ripening date (the early critical transplanting date of the 2nd cropping) was from late-July to early-August. It took about 32 to 39 days in ripening. There was a tendency of SS${\fallingdotseq}$SL$15^{\circ}C$ (${\theta}$15) and the minimum of $10^{\circ}C$ (${\theta}$10), the ten locations could be devided into two ripening groups of ${\theta}$15>${\theta}$10 and ${\theta}$15<${\theta}$10. c. The late critical ripening date was around October 9 at Iri, Chonju, Kwangju and Daeku and around October 28 at Mokpo, Yeosu, Pusan and eheju. Three to four days were more required for a complete ripening of rice, as compared with the above dates. d. There was an overlap of about 12 to 42 days between the first and second cropping when early-maturing varieties requiring an accumulated mean air temperature of $1, 550^{\circ}C$, from transplanting to heading, were grown. Therefore, some varieties which could head with an accumulated daily mean air temperature of 1, 000 to $1, 200^{\circ}C$, should be either developed or some new cultural technology be established in order to have a successful double cropping in rice.

• Korean Journal of Microbiology
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• v.51 no.2
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• pp.97-107
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• 2015

Wetlands constitute a transitional zone between terrestrial and aquatic ecosystems and have unique characteristics such as frequent inundation, inflow of nutrients from terrestrial ecosystems, presence of plants adapted to grow in water, and soil that is occasionally oxygen deficient due to saturation. These characteristics and the presence of vegetation determine physical and chemical properties that affect decomposition rates of organic matter (OM). Decomposition of OM is associated with activities of various extracellular enzymes (EE) produced by bacteria and fungi. Extracellular enzymes convert macromolecules to simple compounds such as labile organic carbon (C), nitrogen (N), phosphorus (P), and sulfur (S) that can be easily taken up by microbes and plants. Therefore, the enzymatic approach is helpful to understand the decomposition rates of OM and nutrient cycling in wetland soils. This paper reviews the physical and biogeochemical factors that regulate extracellular enzyme activities (EEa) in wetland soils, including those of ${\beta}$-glucosidase, ${\beta}$-N-acetylglucosaminidase, phosphatase, arylsulfatase, and phenol oxidase that decompose organic matter and release C, N, P, and S nutrients for microbial and plant growths. Effects of pH, water table, and particle size of OM on EEa were not significantly different among sites, whereas the influence of temperature on EEa varied depending on microbial acclimation to extreme temperatures. Addition of C, N, or P affected EEa differently depending on the nutrient state, C:N ratio, limiting factors, and types of enzymes of wetland soils. Substrate quality influenced EEa more significantly than did other factors. Also, drainage of wetland and increased temperature due to global climate change can stimulate phenol oxidase activity, and anthropogenic N deposition can enhance the hydrolytic EEa; these effects increase OM decomposition rates and emissions of $CO_2$ and $CH_4$ from wetland systems. The researches on the relationship between microbial structures and EE functions, and environmental factors controlling EEa can be helpful to manipulate wetland ecosystems for treating pollutants and to monitor wetland ecosystem services.

• Journal of the Korean Society of Marine Environment & Safety
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• v.13 no.1 s.28
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• pp.9-20
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• 2007

PAHs(Polycyclic Aromatic Hydrocarbons) are widespread contaminants in the marine environment. They are of mainly anthropogenic origin from urban runoff, oil spill and combustion of fossil fuels. Some PAHs are potentially carcinogenic and mutagenic to aquatic organism The contamination of PAHs in the coastal environments has not been well known yet in Korea. This study was carried out to survey the contamination of PAHs in sediments around Gwangyang bay. The Yeosu petrochemical industrial complex, POSCO(Pohang steel company) and Gwangyang container harbor are located around the bay. PAHs in sediment samples were extracted in soxhlet extractor and were identified and quantified by GC-MS(Gas Chromatography-Mass Spectrometry) TOC(Total Organic carbon) and textural parameters in sediment samples were also analyzed 13 species of PAHs were detected at all of the surface sediments. Total PAHs concentrations in the surface sediments ranged from 171.40 to $1013.54{\mu}g/kg$ dry wt.. In most of the surface sediments, Naphthalene was the highest in the range of 14.08 to $691.39{\mu}g/kg$ dry wt. and Anthracene was the lowest in the range of 0.49 to $22.66{\mu}g/kg$ dry wt.. The correlation coefficients between individual PAHs and Total PAHs in the surface sediments were relatively higher in the low molecular compounds such as Naphthalene and Phenanthrene. In the relationship of the P/A(Phenanthrene/Anthracene) ratio and F/P(Fluoranthene/Pyrene) ratio, P/A ratio was generally above 10 and F/P ratio was shown to be above 1 in all sediment samples. These data indicate that PAHs in sediments around Gwangyang bay seem to be of both pyrolytic and petrogenic origin. Total PAHs in the surface sediments were correlated with TOC and textural parameters. The values of PAHs in the surface and core sediments were lower than the biological effect guidelines.

• The KIPS Transactions:PartB
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• v.8B no.6
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• pp.685-692
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• 2001

This paper describes how to disambiguate the aspectual meaning of Japanese expression "-te iru" in Japanese-Korean machine translation Due to grammatical similarities of both languages, almost all Japanese- Korean MT systems have been developed under the direct MT strategy, in which the lexical disambiguation is essential to high-quality translation. Japanese has a progressive aspectual marker “-te iru" which is difficult to translate into Korean equivalents because in Korean there are two different progressive aspectual markers: "-ko issta" for "action progressive" and "-e issta" for "state progressive". Moreover, the aspectual system of both languages does not quite coincide with each other, so the Korean progressive aspect could not be determined by Japanese meaning of " te iru" alone. The progressive aspectural meaning may be parially determined by the meaning of predicates and also the semantic meaning of predicates may be partially reshicted by adverbials, so all Japanese predicates are classified into five classes : the 1nd verb is used only for "action progrssive",2nd verb generally for "action progressive" but occasionally for "state progressive", the 3rd verb only for "state progressive", the 4th verb generally for "state progressive", but occasIonally for "action progressive", and the 5th verb for the others. Some heuristic rules are defined for disambiguation of the 2nd and 4th verbs on the basis of adverbs and abverbial phrases. In an experimental evaluation using more than 15,000 sentances from "Asahi newspapers", the proposed method improved the translation quality by about 5%, which proves that it is effective in disambiguating "-te iru" for Japanese-Korean machine translation.translation quality by about 5%, which proves that it is effective in disambiguating "-te iru" for Japanese-Korean machine translation.anslation.

• Korean Journal of Food Science and Technology
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• v.10 no.1
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• pp.73-77
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• 1978

This experiment was made to select the optimum thickness of the polyethylene (P.E) film for Cheongdo Bansi and Sagoksi in the P.E film storage kept at $0^{\circ}C$. The experimental plots were divided into 4 plots by film thickness (0.04, 0.06, 0.08 and 0.10mm) and those were subdivided into 3 plots by fruits number (3, 10 and 50 persimmons) in each film bags. We investigated five experimental items; the change of loss of weight, firmness, titratable acidity, sugar contents and soluble tannin contents. 1. In the changes of loss of weight, the plot of packing in 0.04mm P.E. film bag with 50 persimmons were more retarded than other plots in Cheongdo Bansi, and packing in 0.08mm with 10 persimmons, 0.04 mm with 50 persimmons were more retarded than other plots in Sagoksi. 2. In the change of softening, the plot of packing in 0.04 mm with 50 persimmons were more retarded than other plots in Cheongdo Bansi and Sagkai. 3. In the changes of titratable acidity, the plot of packing in 0.04 mm with 50 persimmons were more slightly decreased than other plots in Cheongdo Bansu also in Sagoksi, packing in 0.06 mm with 10 persimmons were the same results. 4. In the changes of soluble tannin contents, the plots of packing in 0.06 mm with 10 persimmons, 0.04 mm with 50 perimmons were more ratarded in Chenongdo Bansi, also in Sagoksi, packing in 0.04 mm with 10 persimmons 50 persimmons were the same results. 5. In the changes of soluble tannin contents, the plots of packing in 0.04mm with 3 and 10 persimmons were more slowly decreased than other plots in Cheongdo Bansi and Sagoksi, on. the other hand, pcaking in 0.04mm with 50 persimmins in Cheongdo Bansi and Sagoksi, had not astringent taste at 120 days in storage. Judging through the upper results, the most desirable storage conditions for Cheongdo Bansi and Sagoksi were to pack in P.E film bag of 0.04mm with 50 persimmons.

• Korean Journal of Food Science and Technology
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• v.10 no.1
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• pp.78-82
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• 1978

In a series of studies on the utilization of persimmons, the purpose of this experiment was to examine the optimum thickness of film using different number of persimmons per film bag. 'Fuyu', persimmon variety was used in this investigation. The results obtained were as follows: The optimum thickness of the film bag was 0.08mm, 0.06mm, and 0.04mm for the bags packed with 3, 10 and 50 persimnons, respectively. The changes in the ratio of firmness, loss of fresh weight, titrable acidity and percentage of sugar contents were minimal in these three optimum combinations than the others. These results could be explained by the balanced optimum gas concentration, $CO_2$ 5-10% and $O_2$ 5%, in those three optimum combination. Therefore, it was suggested that the different thickness of film bag needs a particular number of fruits packed per bag for the long term storage in persimmons.

• Korean Journal of Microbiology
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• v.52 no.2
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• pp.140-147
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• 2016

A process for manufacturing virally-safe porcine bone hydroxyapatite (HA) has been developed to serve as advanced xenograft material for dental applications. Porcine bone pieces were defatted with successive treatments of 30% hydrogen peroxide and 80% ethyl alcohol. The defatted porcine bone pieces were heat-treated in an oxygen atmosphere box furnace at $1,300^{\circ}C$ to remove collagen and organic compounds. The bone pieces were ground with a grinder and then the bone powder was sterilized by gamma irradiation. Morphological characteristics such as SEM (Scanning Electron Microscopy) and TEM (Transmission Electron Microscopy) images of the resulting porcine bone HA (THE Graft$^{(R)}$) were similar to those of a commercial bovine bone HA (Bio-Oss$^{(R)}$). In order to evaluate the efficacy of $1,300^{\circ}C$ heat treatment and gamma irradiation at a dose of 25 kGy for the inactivation of porcine viruses during the manufacture of porcine bone HA, a variety of experimental porcine viruses including transmissible gastroenteritis virus (TGEV), pseudorabies virus (PRV), porcine rotavirus (PRoV), and porcine parvovirus (PPV) were chosen. TGEV, PRV, PRoV, and PPV were completely inactivated to undetectable levels during the $1,300^{\circ}C$ heat treatment. The mean log reduction factors achieved were $${\geq_-}4.65$$ for TGEV, $${\geq_-}5.81$$ for PRV, $${\geq_-}6.28$$ for PRoV, and $${\geq_-}5.21$$ for PPV. Gamma irradiation was also very effective at inactivating the viruses. TGEV, PRV, PRoV, and PPV were completely inactivated to undetectable levels during the gamma irradiation. The mean log reduction factors achieved were $${\geq_-}4.65$$ for TGEV, $${\geq_-}5.87$$ for PRV, $${\geq_-}6.05$$ for PRoV, and $${\geq_-}4.89$$ for PPV. The cumulative log reduction factors achieved using the two different virus inactivation processes were $${\geq_-}9.30$$ for TGEV, $${\geq_-}11.68$$ for PRV, $${\geq_-}12.33$$ for PRoV, and $${\geq_-}10.10$$ for PPV. These results indicate that the manufacturing process for porcine bone HA from porcine-bone material has sufficient virus-reducing capacity to achieve a high margin of virus safety.

• Journal of the Korean Society of Food Science and Nutrition
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• v.38 no.4
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• pp.517-524
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• 2009

We collected 177 fishes representing 53 species of fish from the eastern (Pohang), western (Gunsan), and southern (Tongyeong) coasts of Korea, and measured their heavy metal contents. The mean recoveries of the heavy metals extracted from cod muscle (certified reference material, CRM) were $88.7{\sim}100.6%$. The mean levels of the heavy metals in the samples taken from the edible portion of each fish were high in the order of Zn ($8.981{\pm}4.835{\mu}g/g$), Cu ($0.755{\pm}0.507{\mu}g/g$), and Mn ($0.433{\pm}0.699{\mu}g/g$), which are necessary metals in the human body, and then followed by Cr ($0.206{\pm}0.181{\mu}g/g$), Ni ($0.081{\pm}0.110{\mu}g/g$), Pb ($0.038{\pm}0.046{\mu}g/g$), Cd ($0.017{\pm}0.023{\mu}g/g$). The average daily intakes of the heavy metals by the fishes were as follows: Cd (0.81 ${\mu}g$), Cr (9.98 ${\mu}g$), Cu (36.63 ${\mu}g$), Mn (21.01 ${\mu}g$), Ni (3.93 ${\mu}g$), Pb (1.84 ${\mu}g$) and Zn (435.58 ${\mu}g$). The average weekly intakes of Cd, Cu, Pb and Zn by the fishes were 1.35%, 0.12%, 0.86%, and 0.73% respectively, as compared with PTWI (Provisional Tolerable Weekly Intakes) established by FAO/WHO Expert Committee for Food Safety Evaluation.

• The Journal of Korean Medicine Ophthalmology and Otolaryngology and Dermatology
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• v.14 no.2
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• pp.173-182
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• 2001

This Study is attempted in order to observe a clinical analysis from Constitution medical view point about allergic rhinitis. We studied 71 patients who had visited Dept. surgery, opthalmology & otolaryngology, col1ege of Oriental Medicine, Kyungsan University, Pohang, Korea and were treated by medications of Sasang Constitution and Constitution-Acupunture with allergic rhinitis from March 1, 2000 to February 28, 2001. The results were as follows: 1. The sex distribution was 71 males($69\%$), 22 femail($31\%$), In age distribution, the average was 29.6. The peak age was thirties($36.7\%$), teen-ager was $23.9\%,\;fortieth\;was\;15.5\%,\;under\;10\;years\;old\;was\;9.9\%,\;twenties\;was\;7\%,\;fifties\;was\;5.6\%,\;sixtisth\;was\;1.41\%$. 2. In the age of onset, thirties was $29.6\%$, teen-ager was $19.7\%$, twenties was $18.3\%$, under 10 years old and fortieth was $14.1\%$, fifties was $3.8\%$, sixtisth was $1.41\%$. 3 In monthly distribution. september was $25.8\%$, january was $14.1\%$, october was $11.3\%$. november and august was $8.5\%$, april was $7\%$, febuary and may were $5.6\%$, june, july. December were each $4.2\%$, In the distribution of season. the peak season was fall from september to November. 4. In the duration of the disease, 1-3 years was $26.8\%$, 3-5 years was $19.7\%$, 6 months - 1 year $16.9\%$, 5-10 years was $14.1\%$, under 6 months was $11.3\%$, over 10years and over 15 years were each $5.6\%$. 5. In the three main symptom, hydrorrhoea was $71.8\%$, nasal obstruction was $67.6\%$, sneezing was $64.8\%$. In others, fatique was $25.6\%$, headache was $14.1\%$, itching and cough was $11.3\%$, laryngopharyngeal discomfort and red eye were $4.2\%,\;infirmity\;was\;2.8\%$. 6. Patients whose families have allergic disease account for 26 cases($36.6\%$). 7. There was no past history in 37 cases($52.l\%$). In past history distribution, digestive tract disease was $12.7\%$, paranasal sinusitis was $8.5\%$, allergic dermatitis was $7\%$, common cold was $4.2\%$. otitis media, bronchitis, asthma, tonsillitis were $2.8\%$. 8. Sasang Constitution classification was Soyanggin in 52 cases($73.2\%$), Taeumgin in 12 cases($16.9\%$). Soumgin in 7 cases($9.9\%$). 9. In the duration of treatment, it was 1-2 weeks in 26 cases($36.6\%$), 2-4 weeks was $21.1\%$, under 1weeks was $14.1\%$, 4-6 weeks was $11.3\%$, 6-8 weeks was $8.5\%$, 8-10 weeks was $5.6\%$, over 10 weeks was $2.8\%$. 10. We had a follow-up survey the effect of treatment in the 60 cases. there was fair in 25 cases($41.7\%$), good in 21cases($35\%$), excellent in 3cases($5\%$)로 total rate of treatment was $81.7\%$. The case of no change was $16.7\%$, the case of poor was $1.6\%$.