• Korean Journal of Soil Science and Fertilizer
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• v.49 no.6
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• pp.795-806
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• 2016

This study was conducted to improve the continuous techniques for international competitiveness of ginseng industry to Korea-China FTA negotiation and conclusion, and provide the basic information for ginseng industry development of Korea. It was carried out the visiting of the northeastern three provinces (Jilin, Liaoling and Heilongjang) in China for 3-year from 2014 to 2016 and observed the farmers' fields of ginseng cultivation with soil environmental status. The types of ginseng cultivation could be observed in small scales of 0.5~3.0 ha, in middle scales of 4.0~10.0 ha and in large scales of 30~700 ha with the kinds of imhasam, Chinese ginseng, Korean ginseng and western ginseng. Also ginseng was cultivated in newly reclaimed land of forest in two types of direct seeding and transplanting of ginseng seedlings. The field beds of ginseng growing were covered with vinyl films in arch design of 100~130 cm height and vinyl was painted in spraying with blue, green and yellow colours for shading. It was investigated in status of the physico-chemical properties of soils. The physical information on the field soils were silt loam, loam and sandy loam in soil textures, and some plain in low slope, some alluvial fan or local valley in forest of land topography. Soil pH ranged within 5.0~5.2, soil EC was $0.93{\sim}3.78dS\;m^{-1}$, organic matter was $37{\sim}35g\;kg^{-1}$, nitrate nitrogen $63{\sim}490mg\;kg^{-1}$, available $P_2O_5$ $55{\sim}163mg\;kg^{-1}$, and in exchangeable cations, K was 0.30~0.98, Ca was 6.5~14.0, Mg was $1.1{\sim}5.3cmol_c\;kg^{-1}$ in ranges. Farmers used the fertilizer for ginseng cultivation in 10~11 t of compost, $200{\sim}400kg\;ha^{-1}$ of complex fertilizer and $750kg\;ha^{-1}$ of oil cakes. The northeastern three provinces of China can use the newly lands with large areas of ginseng cultivation in soil sickness by continuous cropping. and the soil basic fertility is batter than that of Korean in standard guide of ginseng cultivation soil.

• Geophysics and Geophysical Exploration
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• v.7 no.2
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• pp.109-116
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• 2004

Petroleum reservoir characterization is a process for quantitatively describing various reservoir properties in spatial variability using all the available field data. Porosity and permeability are the two fundamental reservoir properties which relate to the amount of fluid contained in a reservoir and its ability to flow. These properties have a significant impact on petroleum fields operations and reservoir management. In un-cored intervals and well of heterogeneous formation, porosity and permeability estimation from conventional well logs has a difficult and complex problem to solve by conventional statistical methods. This paper suggests an intelligent technique using fuzzy logic and neural network to determine reservoir properties from well logs. Fuzzy curve analysis based on fuzzy logics is used for selecting the best related well logs with core porosity and permeability data. Neural network is used as a nonlinear regression method to develop transformation between the selected well logs and core analysis data. The intelligent technique is demonstrated with an application to the well data in offshore Korea. The results show that this technique can make more accurate and reliable properties estimation compared with previously used methods. The intelligent technique can be utilized a powerful tool for reservoir characterization from well logs in oil and natural gas development projects.

• Journal of Korea Soil Environment Society
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• v.1 no.1
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• pp.89-102
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• 1996

An integrated model is presented to describe underground flow and mass transport, using a multicomponent multiphase approach. The comprehensive governing equation is derived considering mass and force balances of chemical species over four phases(water, oil, air, and soil) in a schematic elementary volume. Compact and systemati notations of relevant variables and equations are introduced to facilitate the inclusion of complex migration and transformation processes, and variable spatial dimensions. The resulting nonlinear system is solved by a multidimensional finite element code. The developed code with dynamic array allocation, is sufficiently flexible to work across a wide spectrum of computers, including an IBM ES 9000/900 vector facility, SP2 cluster machine, Unix workstations and PCs, for one-, two and three-dimensional problems. To reduce the computation time and storage requirements, the system equations are decoupled and solved using a banded global matrix solver, with the vector and parallel processing on the IBM 9000. To avoide the numerical oscillations of the nonlinear problems in the case of convective dominant transport, the techniques of upstream weighting, mass lumping, and elementary-wise parameter evaluation are applied. The instability and convergence criteria of the nonlinear problems are studied for the one-dimensional analogue of FEM and FDM. Modeling capacity is presented in the simulation of three dimensional composite multiphase TCE migration. Comprehesive simulation feature of the code is presented in a companion paper of this issue for the specific groundwater or flow and contamination problems.

• Journal of Korean Society for Atmospheric Environment
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• v.25 no.4
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• pp.275-288
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• 2009

The Korean government strengthened the environmental polices to manage and enhance Metropolitan Area air quality, and also has enforced "Special Act on Seoul Metropolitan Air Quality Improvement (SASMAQI)" issued in Dec. 2004. Recently government expanded the Seoul Metropolitan Air Quality Management District (SMAQMD) to the outskirts satellite cities of Seoul area through the "Revised Law Draft of SASMAQI". The SMAQMD has been alloted the allowable emission loads to the local governments on the basis of the carrying $PM_{10}$ capacity. However, in order to establish the effective air quality control strategy for $PM_{10}$, it is necessary to understand the corresponding sources which have a potential to directly impact ambient $PM_{10}$ concentration. To deal with the situations, many receptor methodologies have been developed to identify the origins of pollutants and to determine the contributions of sources of interests. The objective of this study was to extensively identify $PM_{10}$ sources and to estimate their contributions at the metropolitan area. $PM_{10}$ samples were simultaneously collected at the 3 semi-industrialized local cities in the Seoul metropolitan area such as Hwasung-si, Paju-si, and Icheon-si sites from April 15 to May 31, 2007. The samples collected on the teflon membrane filter by one $PM_{10}$ cyclone sampler were analyzed for trace metals and soluble ions and samples on the quartz fiber filter by another sampler were analyzed for OC and EC. Source apportionment study was then performed by using a positive matrix factorization (PMF) receptor model. A total of 6 sources were identified and their contributions were estimated in each monitoring site. Contribution results on Hwasung, Paju, and Icheon sites were as follows: 33%, 27%, and 27% from soil source, 26%, 26%, and 21% from secondary aerosol source, 11%, 11%, and 12% from biomass burning, 12%, 6%, and 5% from sea salt, 7%, 15%, and 19% from industrial related source, and finally 11%, 15%, and 16% from mobile and oil complex source, respectively. This study provides information on the major sources affecting air quality in the receptor sites and thus it will help to manage the ambient air quality in the metropolitan area by establishing reasonable control strategies, especially for the anthropogenic emission sources.

• Nutritional Sciences
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• v.7 no.4
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• pp.223-234
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• 2004

The aim of this study was to investigate intake of health foods and supplements and its associated factors in middle and old-aged adults in order to contribute to health promotion of Korean population by providing a guide for proper use of health foods and supplements. About 69% of the subjects reported that they were currently taking health foods and supplements or had experiences of having them in the past, whereas 31.2 % reported they had never taken them. The most commonly used type of health foods and supplements was vitamin C as reported by 41.8% followed by others such as lactobacillus products, multi-vitamins, tonic medicine and cardiotonic drug, artificially processed Ginseng foods, vitamin B complex, enzyme supplement, calcium, aloe, apricot extract products, chitosan products, loyal honey, squalene, refined fish oil and iron products. The major reason for taking health foods and supplements was 'to protect the weak constitution' with 155 (42.1%) responses, and the motive for the intake was the suggestion from family-relatives with 235 (63.9%) responses, and the place of purchase was pharmacy with 140 (38.0%) responses, the average monthly expense was 20,000-40,000 won with 140 (26.2%) responses, and effects after the intake was 'so and so' with 180 (33.6%) responses as the highest. More health foods and supplements were consumed as age and education were statistically significantly increased (p<0.05). For health and lifestyle and the intake of health foods and supplements, perceived health status, the presence of illness, and the presence of health management were statistically significant (p<0.05). Male subjects than female subjects and the 30s than the 405 and 50s were appeared to have poorer dietary behaviors (p<0.05). For the health locus of control and the intake of health foods and supplements, the health locus of control score was 22.82 for consumers and 22.79 for non-consumers, showing no significant difference. Logistic regression analysis was performed to find out major factors that affect the intake of health foods and supplements, in which gender, education, smoking, perceived health status, the presence of illness, and health management were significant to the intake of health foods and supplements. It is shown that subjects with perception and attitude of 'health foods and supplements are useful in health maintenance and disease prevention' and 'the information and variety for health foods and supplements are great' have higher probability of taking health foods and supplements.

• Elastomers and Composites
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• v.34 no.2
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• pp.135-146
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• 1999

The thermal degradation kinetics of SBR and tire were studied using a conventional thermogravimetric analysis in the stream nitrogen at a heating rate of 5, 10, 15, $20^{\circ}C/min$, respectively. Thermogravimetric curves and their derivatives were analyzed using various analytical methods to determine the kinetic parameters. The degradation of the SBR and tire was found to be a complex process which has multi-stages. The Friedman method gave average activation energies for the SBR and tire of 247.53kJ/mol and 230.00kJ/mol, respectively. Mean-while, the Ozawa method Eave 254.80kJ/mol and 215.76kJ/mol. It would appear that either. Friedman's differential method or Ozawa's integral method provided satisfactory mathematical approaches to determine the kinetic parameters for the degradation of the SBR and tire. Approximately 86% and 55% of oil products were obtained at a final temperature of $700^{\circ}C$ and a heating rate of $20^{\circ}C/min$ for the SBR and tire respectively.

• Journal of Korean Tunnelling and Underground Space Association
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• v.23 no.6
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• pp.503-516
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• 2021

Autonomous fire detection and suppression system requires advanced technology for complex detection technology and injection/control technology for accurate hitting by fire location. Also, foam spraying should be included to respond to oil fires. However, when a single spray monitor is used in common, water and foam spray properties appear different, so for accurate fire suppression, research on the spray trajectory and distance will be required. In this study, experimental studies and numerical analysis studies were combined to analyze the foam spray characteristics through the spray monitor developed for the establishment of an autonomous fire extinguishing system. For flow analysis of foam injection, modeling was performed using OpenFOAM analysis software, and the commonly used foaming agent (Aqueous Film-Forming Foam) was applied for foam properties. The injection distance analysis was performed according to the injection pressure and the injection angle according to the form of the foam, and at the same time, the results were verified and presented through the injection experiment.

• Journal of Embryo Transfer
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• v.14 no.1
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• pp.17-22
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• 1999

To investigate the maturational and development competece of porcine oocytes of different diameter groups, oocytes were obtained by aspiration from slaughterdhouse ovaries. After washing three times in NCSU23 medium, each cumulus-oocyte complex was transferred into a $8{mu}ell$ drop of the maturation medium (one oocyte per drop) under paraffin oil. The diameter without zona pellucida of oocytes was measured with micor-calibrator (Mikrometer, E. Leitz) on a screen connected to a VCR on an inverted microscope $(200\times)$. After being measured, the oocytes were divided into 6 groups according to their diameter size : <105, 105 to < 110, 110 to < 115, 115 to < 120, 120 to < 125 and > $125{\mu}{\textrm}{m}$, and in vitro maturation (IVM), fertillzation (IVF) and production (IVP) of oocytes / embryo was performed. The rates of in vitro maturation on oocytes in the greater 105 ${\mu}{\textrm}{m}$ size groups(91.8~100%) were significantly (P<0.05) higher than in the < 105 ${\mu}{\textrm}{m}$ group(66.7%). The rates of sperm penetration were significantly (P<0.05) low in < $105{\mu}{\textrm}{m}$ group (50.0%) than others groups (81.6~85.5%). But the plyspermic fertilization rate was significantly (P<0.05) higher in < $110{\mu}{\textrm}{m}$ oocytes groups than in the $110\leq{\mu}{\textrm}{m}$ size groups. The rates of cleavage and development to blastocysts rose as oocytes diameter increased, however, while oocytes over $120{\mu}{\textrm}{m}$ in diameter failed to develop to blastocysts. There results suggest that porcine oocytes have acquired full meiotic competece at a diameter of $105{\mu}{\textrm}{m}$ but not yet attended full development competence to blastocyst and that oocytes have acquired full development competence at a diameter of $110{\mu}{\textrm}{m}$.

• The Korean Journal of Petroleum Geology
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• v.4 no.1_2 s.5
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• pp.27-39
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• 1996

In the Cretaceous, the Gulf Coast Basin evolved as a marginal sag basin. Thick clastic and carbonate sequences cover the disturbed and diapirically deformed salt layer. In the Cretaceous the salinities of the Gulf Coast Basin probably matched the Holocene Persian Gulf, as is evidenced by the widespread development of supratidal anhydrite. The major Lower Cretaceous reservoir formations are the Cotton Valley, Hosston, Travis Peak siliciclastics, and Sligo, Trinity (Pine Island, Pearsall, Glen Rose), Edwards, Georgetown/Buda carbonates. Source rocks are down-dip offshore marine shales and marls, and seals are either up-dip shales, dense limestones, or evaporites. During this period, the entire Gulf Basin was a shallow sea which to the end of Cretaceous had been rimmed to the southwest by shallow marine carbonates while fine-grained terrigengus clastics were deposited on the northern and western margins of the basin. The main Upper Cretaceous reservoir groups of the Gulf Coast, which were deposited in the period of a major sea level .rise with the resulting deep water conditions, are Woodbinefruscaloosa sands, Austin chalk and carbonates, Taylor and Navarro sandstones. Source rocks are down-dip offshore shales and seals are up-dip shales. Major trap types of the Lower and Upper Cretaceous include salt-related anticlines from low relief pillows to complex salt diapirs. Growth fault structures with rollover anticlines on downthrown fault blocks are significant Gulf Coast traps. Permeability barriers, up-dip pinch-out sand bodies, and unconformity truncations also play a key role in oil exploration from the Cretaceous Gulf Coast reservoirs. The sedimentary sequences of the major Cretaceous reseuoir rocks are a good match to the regressional phases on the global sea level cuwe, suggesting that the Cretaceous Gulf Coast sedimentary stratigraphy relatively well reflects a response to eustatic sea level change throughout its history. Thus, of the three main factors controlling sedimentation (tectonic subsidence, sediment input, and eustatic sea level change) in the Gulf Coast Basin, sea-level ranks first in the period.

• Journal of the Korean Society of Marine Environment & Safety
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• v.14 no.4
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• pp.257-266
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• 2008

PAHs are of mainly anthropogenic origin from urban runoff, oil spill and combustion of fossil fuels. Some PAHs are potentially carcinogenic and mutagenic to aquatic organisms. This study was carried out to survey the contamination of PAHs in the column sediments around Gwangyang bay. Yeosu petrochemical industrial complex, POSCO(Pohang steel compony) and Gwangyang container harbor are located near the bay. The column sediments were collected at 4 stations(A, B, C and D) and fractionated at intervals of two-centimeter depth on July 29, 1999. PAHs in colmn sediment samples were extracted in soxhlet extractor and were identified and quantified by GC-MS. PAHs compounds were analyzed and found to be 13 species. Total PAHs concentrations in the column sediments ranged from 275.04 to 2,838.64${\mu}g/kg$ dry wt. Naphthalene had the highest concentration in the range of 40.60 to 2,294.06${\mu}g/kg$ dry wt. and Anthracene had the lowest concentration in the range of 2.63 to 11.30${\mu}g/kg$ dry wt. The correlation coefficients between individual PAHs and total PAHs in the column sediments were relatively higher in the low molecular compounds such as Naphthalene, Acenaphthylene and Phenanthrene. The relationship between the P/A(Phenanthrene/Anthracene)ratio and F/P(Fluoranthene/Pyrene)ratio showed that P/A ratio was generally above 10 and F/P ratio was above 1 in all sediment samples. These data indicate that PAHs in the column sediments around Gwangyang bay seem to be of both pyrolytic and petrogenic origin The values of PAHs in the column sediments were lower than the biological effect guidelines.