• Korean Journal of Ecology and Environment
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• v.34 no.1 s.93
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• pp.1-8
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• 2001

During April 1993 to November 1994, cations, anions, and conductivity were analyzed to examine how summer monsoon influences the ionic content of Taechung Reservoir, Korea. Interannual variability of ionic content reflected hydrological characteristics between the two years(high-flood year in 1993 vs. draught year in 1994). Cations, anions and conductivity were lowest during peak inflow in 1993 and highest during a drought in 1994. Floods in 1993 markedly decreased total salinity as a result of reduced Ca$^{2+}$ and HCO$_{3}\;^{-}$ and produced extreme spatial heterogeneity (i.e., longitudinal, vertical, and horizontal variation) in ionic concentrations. The dominant process modifying the longitudinal (the headwaters-to-downlake) and vertical (top-to-bottom) patterns in salinity was an interflow current during the 1993 monsoon. The interflow water plunged near a 27${\sim}$37 km-location (from the dam) of the mid-lake and passed through the 10${\sim}$30m stratum of the reservoir, resulting in an isolation of epilimnetic high conductivity water (>100 ${\mu}$S/cm) from advected river water with low conductivity (65${\sim}$75 ${\mu}$S/cm), During postmonsoon 1993, the factors regulating salinity differed spatially; salinity of downlake markedly declined as a result of dilution through the mixing of lake water with river water, whereas in the headwaters it increased due to enhanced CaCO$_{3}$ (originated from limestone/metamorphic rock) of groundwaters entering the reservoir. This result suggests an importance of the basin geology on ion compositions with hydrological characteristics. In 1994, salinity was markedly greater (p<0.001) relative to 1993 and ionic dilution did not occur during the monsoon due to reduced inflow. Overall data suggest that the primary factor influencing seasonal ionic concentrations and compositions in this system is the dilution process depending on the intensity of monsoon rainfall.

• Asian Pacific Journal of Cancer Prevention
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• v.15 no.19
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• pp.8311-8317
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• 2014

Background: Evidence supporting an association between the 8q24 rs4242382-A polymorphism and prostate cancer (PCa) risk has been reported in North American and Europe populations, though data from Asian populations remain limited. We therefore investigated this association by clinical detection in China, and meta-analysis in Asian, Caucasian and African-American populations. Materials and Methods: Blood samples and clinical information were collected from ethnically Chinese men from Northern China with histologically-confirmed PCa (n=335) and from age-matched normal controls (n=347). The 8q24 (rs4242382) gene polymorphism was genotyped by polymerase chain reaction-high-resolution melting analysis. We initially analyzed the associations between the risk allele and PCa and clinical covariates. A meta-analysis was then performed using genotyping data from a total of 1,793 PCa cases and 1,864 controls from our study and previously published studies in American and European populations, to determine the association between PCa and risk genotype. Results: The incidence of the risk allele was higher in PCa cases than controls (0.222 vs 0.140, $P=7.3{\times}10^{-5}$), suggesting that the 8q24 rs4242382-A polymorphism was associated with PCa risk in Chinese men. The genotypes in subjects were in accordance with a dominant genetic model (ORadj=2.03, 95%CI: 1.42-2.91, $Padj=1.1{\times}10^{-4}$). Presence of the risk allele rs4242382-A at 8q24 was also associated with clinical covariates including age at diagnosis ${\geq}65$ years, prostate specific antigen >10 ng/ml, Gleason score <8, tumor stage and aggressive PCa, compared with the non-risk genotype ($P=4.6{\times}10^{-5}-3.0{\times}10^{-2}$). Meta-analysis confirmed the association between 8q24 rs4242382-A polymorphism and PCa risk (OR=1.62, 95%CI: 1.39-1.88, $P=1.0{\times}10^{-5}$) across Asian, Caucasian and African American populations. Conclusions: The replicated data suggest that the 8q24 rs4242382-A variation might be associated with increased PCa susceptibility in Asian, Caucasian and African American populations. These results imply that this polymorphism may be a useful risk biomarker for PCa in multi-ethnic populations.

• Korean Journal of Environmental Agriculture
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• v.37 no.2
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• pp.73-78
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• 2018

BACKGROUND: Soil salinity of reclaimed tidal land in Korea is highly important factor. High salinity is harmful to crop productivity. Jerusalem artichoke (Helianthus tuberosus L.) is known to be salt-tolerant and has high adaptability to diverse pedo-climatic conditions. The objective of this study was to assess the changes of soil properties and crop productivity according to salt concentration in the reclaimed tidal lands. METHODS AND RESULTS: Experimental sites were selected at Saemangeum ($35^{\circ}46^{\prime}N$, $126^{\circ}37^{\prime}E$) reclaimed tidal land, and their dominant soil series were Munpo (coarse loamy, mixed, non-acid, mesic, typic Fluvaquents). H. tuberosus L were collected from 12 locations across Korea. Tubers were planted at $75{\times}25cm$ with EC 2 to $7dS\;m^{-1}$. Soil samples were periodically collected from both 0~20 cm and 20~40 cm depths of each site. Soil salinity and soil moisture contents were varied depending on weather conditions. Soil electrical conductivity varied from 1.0 to $5.9dS\;m^{-1}$, and soil moisture contents varied from 9.2 to 28.7%. The white-colored tubers of H. tuberosus L. collected from 'Yeongwol-gun' exhibited the highest height (207 cm), followed by the white-colored tubers of H. tuberosus L. collected from 'Iksan-si'(202 cm). The white-colored tubers of H. tuberosus L. collected from 'GyeongJu-si' showed the highest yield (549 kg/10a). The purple-colored tubers of H. tuberosus L. collected from 'Yeongwol-gun' showed the highest yield (615 kg/10a). CONCLUSION: Our results indicate that the plant height and tuber yield did not appear to be correlated. Considering yield and inulin content, the GyeongJu-si seemed to be suitable as the white-colored tubers of H. tuberosus L. and the Yeongwol-gun seemed to be suitable as the purple-colored tubers of H. tuberosus L. in the reclaimed tidal lands. However, it is necessary to consider the relationship between the inulin content and the yield.

• Korean Journal of Environment and Ecology
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• v.34 no.1
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• pp.18-26
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• 2020

Echinosophora koreensis (Nakai) Nakai an endemic plant with limited distribution in some parts of the Korean Peninsula, is designated as "Endangered" species on the IUCN Red List. The species is under the threat of deterioration in nature due to various environmental changes causing loss of natural habitats. We investigated the distribution pattern and population structure of E. koreensis to serve as a basic reference for identifying the dynamics and persistence of natural populations of this species in the future. To determine the characteristics of the E. koreensis population, we laid two to three large plots sized 20m×30m on the ridgeline as the reference in Yanggu, Chuncheon, and Hongcheon and laid four to seven small quadrats sized 1m×1m on the transect. A total of 530 plots were laid, 10 each at 2m interval, to measure the number of the stems, the number of fruiting, height, and other factors. The collected distribution information was compared with the existing IUCN assessed categories by applying IUCN Red List ver 3.1 Criteria B. The average population density of the three surveyed areas was 3.47 stem/㎡; the density of each area was 3.95 stems/㎡ in Yanggu, 3.37 stems/㎡ in Chuncheon, and 2.87 stems/㎡ in Hongcheon. The number of fruiting per stem was 0.0038, indicating only 7 fruits out of 1,837 stems and that vegetative reproduction is likely to be more dominant than sexual reproduction. The distribution tendency of population density in the small plots in three surveyed areas showed that the density of E. koreensis tended to decrease toward the center of the forest with low crown openness and around the mountain ridge with high crown openness. It indicated that the quantity of light could be a very important factor for the growth of individuals of this species. The analysis of the heights of individuals present in the surveyed plots showed a range of 2.3 ~ 68.5cm and an average of 20.1cm. An analysis on the stage-structure of the E. koreensis population based on the sieve height found that the appearance frequency decreased with increasing height above 15 ~ 20cm and that the percentage of individuals lower than 10cm, which were presumed to be seedlings, was severely low, indicating a necessity of study on the population sustainability based on the monitored data. The occupied area calculated with the collected species distribution information was 200㎢, indicating the EN category according to the IUCN Red List Reference B.

• Journal of the Korean Society of Groundwater Environment
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• v.4 no.1
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• pp.41-53
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• 1997

Geochemical data of soil and water samples were presented in order to assess the environmental impart for drinking water sites. Microscopic observation of rock samples and physical and chemical analysis of soil and water samples were undertaken. The geology of study areas are classified into three groups such as granitic rocks, meta-sedimentary rocks and sedimentary rocks. Enrichment of heavy metals derived from those rocks is not found in this study areas. Soils were analyzed for Cu, Pb, Zn, Cd and Cr using AAS extracted by HNO$_3$+HClO$_4$ and 0.1 N HCl. Heavy metal concentrations in soils are within the range of those in uncontaminated soils. In comparison of metal contents extracted by 0.1 N HCl and HNO$_3$+HC1O$_4$, less than 10% of the heavy metals are present in the exchangeable fraction. In particular, an pollution index has been proposed to assess the degree of soil contamination. Pollution index in soils are between 0.03 and 0.47 therefore, soils are not polluted with heavy metals. Deep groundwaters within granitic rocks have been evolved into Na$\^$＋/-HCO$_3$$\^$-/ type, whereas other deep groundwaters evolved into Ca$\^$2＋/-HCO$_3$$\^$-/ type. The predominance of Na$\^$＋/ over Ca$\^$2＋/ in deep groundwaters within granitic rocks is a result of dissolution of plagioclase, but for sedimentary and meta-sedimentary rocks, dissolution of calcite is a dominant factor for their hydrogeochemistry. The pH, conductivity and contents of the most dissolved ions in the water increase with depth. Shallow groundwaters, however, are highly susceptible to pollution owing to agricultural activities, considering the fact that high contents of nitrate, chloride and potassium, and high K/Na ratio are observed in some shallow groundwaters. In a thermodynamic approach, most natural water samples are plotted within the stability fields of kaolinite and smectite. Therefore, microcline and other feldspars will alter to form clay minerals, such as kaolinite and smectite. From the modelling for water-rock interactions based on mass balance equation, models accord well with behavior of the ions and results of thermodynamic studies are derived.

• Journal of the Korean earth science society
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• v.21 no.5
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• pp.611-622
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• 2000

To investigate the exchange rates of mercury(Hg) across soil-air boundary, we undertook the measurements of Hg flux using gradient technique from a major waste reclamation site, Nan-Ji-Do. Based on these measurement data, we attempted to provide insights into various aspects of Hg exchange in a strongly polluted soil environment. According to our analysis, the study site turned out to be not only a major emission source area but also a major sink area. When these data were compared on hourly basis over a full day scale, large fluxes of emission and deposition centered on daytime periods relative to nighttime periods. However, when comparison of frequency with which emission or deposition occurs was made, there emerged a very contrasting pattern. While emission was dominant during nighttime periods, deposition was most favored during daytime periods. When similar comparison was made as a function of wind direction, it was noticed that there may be a major Hg source at easterly direction to bring out significant deposition of Hg in the study area. To account for the environmental conditions controlling the vertical direction of Hg exchange, we compared environmental conditions for both the whole data group and those observed from the wind direction of strong deposition events. Results of this analysis indicated that the concentrations of pollutant species varied sensitively enough to reflect the environmental conditions for each direction of exchange. When correlation analysis was applied to our data, results indicated that windspeed and ozone concentrations best reflected changes in the magnitudes of emission/deposition fluxes. The results of factor analysis also indicated the possibility that Hg emission of study area is temperature-driven process, while that of deposition is affected by a mixed effects of various factors including temperature, ozone, and non-methane HCs. If the computed emission rate is extrapolated to the whole study area we estimate that annual emission of Hg from the study area can amount to approximately 6kg.

• Korean Journal of Soil Science and Fertilizer
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• v.45 no.4
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• pp.503-510
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• 2012

Microwave radar can penetrate cloud cover regardless of weather conditions and can be used day and night. Especially a A ground-based polarimetric scatterometer operating at multiple frequencies can continuously monitor the crop conditions. We analyzed scattering characteristics of rice and soybean using pauli decomposition method. Surface scattering (${\alpha}$) is the dominant component over the entire stages for all bands and pauli decomposition value was the highest for L-band. Double bounce scattering (${\beta}$) and volume scattering (${\gamma}$) were approximately equal for C-band and volume scattering was higher than double bounce scattering for X-band in rice field. In soybean, double bounce scattering becomes higher than volume scattering during the R2 stage (DOY 224) and there was a significant difference between the two components after the R4 stage (DOY 242) for L-band. The maximum growth stage of soybean can also be detected using L-band double bounce scattering. The peak of double bounce effect coincides with the peak of growth biophysical variables on DOY 271. We found that pauli decomposition can provide insight on the relative magnitude of different scattering mechanisms during the rice and soybean growth cycle.

• Korean Journal of Cognitive Science
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• v.15 no.2
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• pp.1-15
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• 2004

The structure of sensibility from motion was developed for the purpose of understanding relationship between sensibilities and physical factors to apply it to dynamic visual display. Seventy adjectives were collected by assessing adequacy to express sensibilities from motion and reporting sensibilities recalled from dynamic displays with achromatic color. Various motion displays with a moving single dot were rated according to the degree of sensibility corresponding to each adjective, on the basis of the Semantic Differential (SD) method. The results of assessment were analyzed by means of the factor analysis to reduce 70 words into 19 fundamental sensibilities from motion. The Multidimensional Scaling (MDS) technique constructed the sensibility space in motion, in which 19 sensibilities were scattered with two dimensions, active-passive and bright-dark Motion types systemically varied in kinematic factors were placed on the two-dimensional space of motion sensibility, in order to analyze important variables affecting sensibility from motion. Patterns of placement indicate that speed and both of cycle and amplitude in trajectories tend to partially determine sensibility. Although color and motion affected sensibility according to the in dimensions, it seemed that combination of motion and color made each have dominant effect individually in a certain sensibility dimension, motion to active-passive and color to bright-dark.

• The Korean Journal of Pain
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• v.5 no.1
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• pp.37-43
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• 1992

Postoperative hypoxemia in the absence of hypoventilation occurs more often after thoracic or upper abdominal surgery than lower abdominal operations or surgery on extremities. Although the factors which produce postoperative alveolar collapse have not been fully evaluated, the dominant factor of postoperative hypoxemia is shunt of blood passing collapsed alveoli and the postoperative pain is associated with restriction of depth of breathing, sighing and movement. In 1979, the first successful clinical usage of epidurally administered morphine for control of postoperative pain was reported by Behar and associates. This study was carried out for twenty patients who received posterolateral thoracostomy with bleb resection between May 1990 and May 1991 and who were primary spontaneous recurrent pneumothoraxes under general endotracheal anesthesia. For the relief of post-thoracotomy pain following of the general anesthesia, we selected ten patients as control group which were treated intermittently IM with injection of pethidine(50 mg) according to the conventional method and another ten patients as study group which were managed with thoracic epidural analgesia. The tip of the catheter was inserted to T4-5 epidural space through T12-L1 or L1-2 interspinous region before the induction of the general anesthesia and then the epidural analgesics(0.25% bupivacaine 15 ml+morphine 3 mg) was injected once a day via the catheter until 4 th POD in the study group. The epidural catheters were removed at postoperative 4 th day in study group. Clinical observations were done about vital signs, ABG, tidal volume, FVC and occurence of adverse effects during postoperative 2hr, 8hr, 1st day, 2nd day, 7th day in both groups. The results were as follows; (1) The values of $V_T$ and FVC were significantly improved in study group(85% and 66%) as compared with control group(76% and 61%) during the postoperative 4 day of the epidural analgesia. (2) After the end of the epidural analgesia(7th POD), the values of FVC were improved invertly rather in control group(98%) than study group(84%). It suggested that the reduction of FVC in study group were caused by the raised pain sensitivity following the end of epidural analgesia. (3) The side effects of epidural analgesia such as transient urinary retention(2 cases), itching sensation(1) and headache(1) were noted.

• Journal of Intelligence and Information Systems
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• v.24 no.3
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• pp.89-117
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• 2018

The Korean companies are intensifying competition with not only domestic companies but also foreign companies in globalization. In this environment, it is essential activities not only for large companies but also Small and Medium Enterprises (SMEs) to get and develop the core competency. Particularly, SMEs that are inferior to resources of various aspects, such as financial resources etc., can make innovation through effective R&D investment. And then, SMEs can occupy a competency and can be survive at the environment. Conventionally, the method of "self-development" by using only the internal resources of the company has been dominant. Recently, however, R&D method through cooperation, also called "Open Innovation", is emerging. Especially SMEs are relatively short of available internal resources. Therefore, it is necessary to utilize technology and resources through cooperation with external companies(such as joint development or contract development etc.) rather than self-development R&D. In this context, we confirmed the effect of SMEs' factors on sales in Korea. Specifically, the factors that SMEs hold are classified as 'Technical characteristic', 'Company competency', and 'R&D activity' and analyzed how they influence the sales achieved as a result of R&D. The analysis was based on a two-year statistical survey conducted by the Korean government. In addition, we confirmed the influence of the factors on the sales according to the R&D method(Self-Development vs. Open Innovation), and also observed the influence change in 29 industrial categories. The results of the study are summarized as follows: First, regression analysis shows that twelve factors of SMEs have a significant effect on sales. Specifically, 15 factors included in the analysis, 12 factors excluding 3 factors were found to have significant influence. In the technical characteristic, 'imitation period' and 'product life cycle' of the technology were confirmed. In the company competency, 'R&D led person', 'researcher number', 'intellectual property registration status', 'number of R&D attempts', and 'ratio of success to trial' were confirmed. The R&D activity was found to have a significant impact on all included factors. Second, the influence of factors on the R&D method was confirmed, and the change was confirmed in four factors. In addition, these factors were found that have different effects on sales according to the R&D method. Specifically, 'researcher number', 'number of R&D attempts', 'performance compensation system', and 'R&D investment' were found to have significant moderate effects. In other words, the moderating effect of open innovation was confirmed for four factors. Third, on the industrial classification, it is confirmed that different factors have a significant influence on each industrial classification. At this point, it was confirmed that at least one factor, up to nine factors had a significant effect on the sales according to the industrial classification. Furthermore, different moderate effects have been confirmed in the industrial classification and R&D method. In the moderate effect, up to eight significant moderate effects were confirmed according to the industrial classification. In particular, 'R&D investment' and 'performance compensation system' were confirmed to be the most common moderating effect by each 12 times and 11 times in all industrial classification. This study provides the following suggestions: First, it is necessary for SMEs to determine the R&D method in consideration of the characteristics of the technology to be R&D as well as the enterprise competency and the R&D activity. In addition, there is a need to identify and concentrate on the factors that increase sales in R&D decisions, which are mainly affected by the industry classification to which the company belongs. Second, governments that support SMEs' R&D need to provide guidelines that are fit to their situation. It is necessary to differentiate the support for the company considering various factors such as technology and R&D purpose for their effective budget execution. Finally, based on the results of this study, we urge the need to reconsider the effectiveness of existing SME support policies.