• Journal of the Korean Association of Geographic Information Studies
• /
• v.15 no.1
• /
• pp.197-210
• /
• 2012

The KOrea Multi-Purpose SATellite(KOMPSAT)-2 has a capability to provide a cross-track stereo imagery using two different orbits for generating various spatial information. However, in order to fully realize the potential of the KOMPSAT-2 stereo imagery in terms of mapping, various tests are necessary. The purpose of this study is to evaluate the possibility of mapping using the KOMPSAT-2 stereo imagery. For this, digital plotting was conducted based on the stereoscopic images. Also the Digital Elevation Model(DEM) and an ortho-image were generated using digital plotting results. An accuracy of digital plotting, DEM, and ortho-image were evaluated by comparing with the existing data. Consequently, we found that horizontal and vertical error of the modeling results based on the Rational Polynomial Coefficient(RPC) was less than 1.5 meters compared with the Global Positioning System(GPS) survey results. The maximum difference of vertical direction between the plotted results in this study and the existing digital map on the scale of 1/5,000 was more than 5 meters according as the topographical characteristics. Although there were some irregular parallax on the images, we realized that it was possible to interpret and plot at least seventy percent of the layer which was required the digital map on the scale of 1/5,000. Also an accuracy of DEM, which was generated based on the digital plotting, was compared with the existing LiDAR DEM. We found that the ortho-images, which were generated using the extracted DEM in this study, sufficiently satisfied with the requirement of the geometric accuracy for an ortho-image map on the scale of 1/5,000.

• Journal of the Korean Geotechnical Society
• /
• v.25 no.1
• /
• pp.65-76
• /
• 2009

The unsaturated characteristics of Korean weathered granite soils have been studied to investigate the influence of saturated permeability, rainfall intensity and soil-water characteristic curve (SWCC) on the slope stability. The upper, average and lower SWCCs were estimated from the publication and experimental results using the statistical concept. The roughly estimated SWCC can be used for the soils without experimental results by relating SWCC with the particle size distribution curve. An appropriate ratio between the saturated permeability and the rainfall intensity ($k_s$/i) was also suggested for practical use in designing the slopes by investigating the time-dependent variation of slope instability during the rainfall. The slope stability was deteriorated from the initiation of rainfall and recovered again after the factor of safety reached the critical value. The FS of the slope decreased at first and then increased after reaching the critical value during the rainfall. As a result, the slope instability was not related with an absolute rainfall intensity but with the ratio between the saturated permeability and the rainfall intensity. In case of the upper SWCC, the critical condition occurred when the ratio between the saturated permeability and the rainfall intensity was in the range of $1.0{\sim}2.0$.

• Journal of the Computational Structural Engineering Institute of Korea
• /
• v.25 no.6
• /
• pp.533-540
• /
• 2012

Rubber laminated bearings with lead core are highly affected by changes in temperature because key materials which are rubber and lead have temperature dependencies. In this study, two full scale LRB(D800, S=5) are manufactured and temperature dependency tests on shear properties are accomplished. The shear properties at the 3rd cycle are used at $-10^{\circ}C$, $0^{\circ}C$, $10^{\circ}C$, $20^{\circ}C$, $30^{\circ}C$, $40^{\circ}C$ respectively. The double shear configuration, simultaneously testing two pieces, is applied for compression shear test in order to minimize the friction effects due to the test machine, described in ISO 22762-1:2010. Characteristic strength, post-yield stiffness, effective stiffness, equivalent damping ratio are estimated and presented coefficient due to the temperature changes.

• Journal of the Korea Organic Resources Recycling Association
• /
• v.29 no.3
• /
• pp.17-25
• /
• 2021

This study was conducted to investigate effects of mixture with dried food waste powder (FWP) and mixed organic fertilizer (MOF) on growth of pakchoi. As compared with non-fertilizer treatment (NF) or control (MOF treatment), growth of pakchoi in FWP treatments (2,500 kg/ha, 5,000 kg/ha, 10,000 kg/ha) was inhibited by salt (NaCl) content in the FWP. In comparison with control, mixtures of MOF and FWP (FWP10, FWP20, and FWP30 treatment) were not significantly different, and their salt content correlated with pakchoi growth factors negatively (P<0.05). Applied of FWP10, (FWP10: 2,500 kg/ha, 2FWP10: 5,000 kg/ha, 3FWP10: 7,500 kg/ha, 4FWP10: 10,000 kg/ha), growth factors of FWP10, 2FWP10 and 3FWP10 treatment were not significantly different than those of chemical fertilizer treatment, and of 4FWP10 decreased. Correlation coefficient between NaCl supply by FWP10 application and growth factor was negative (P<0.01). These results indicated that FWP was used as another source of organic fertilizer, and the organic fertilizers blending with FWP inhibited a pakchoi growth by increase of salt content containing in the them or of salt supplying amount after their application.

• Economic and Environmental Geology
• /
• v.40 no.3 s.184
• /
• pp.263-275
• /
• 2007

The purpose of this study was to show the pollution characteristics of hazardous elements from roadside dust in the Gwangju city. We collected 47 samples from November to December in 2004 and separated four groups such as residential area, industrialized area, downtown area and heavy traffic area fer characteristics comparison on hazardous elements. Roadside dust mostly consisted of quartz, albite, microcline, muscovite in XRD analysis. Content of hazardous elements varied: As $3.4{\sim}11.9 ppm$, Cd $0.2{\sim}28.2 ppm$, Co $32{\sim}526 ppm$, Cr $25{\sim}526 ppm$, Cu $11{\sim}375 ppm$, Ni $14{\sim}247 ppm$, Pb $13{\sim}413 ppm$ and Zn $101{\sim}972 ppm$. Average contents of hazardous elements of Zn>Cu>Pb>Cr>Co>Ni>Cd. Content of hazardous elements was low in residential area, whereas that of heavy metal was much the same in both in heavy traffic area. Content of hazardous elements such as Cd, Co, Cr, Cu, Ni, Pb, Zn was found to be particularly high in industrialized area. According to these results it was possible to presume that industrialized area was affected by industry activity such as machinery, petrochemical, automobile and electronics industry. The SEM analysis, detected Pb, Cr, Ni, and Fe particles in samples of industrialized area contaminated by industry activity. The correlation coefficient table resulted from the samples of roadside dust showed that there was same direction increase of content between elements. In other words, when the content of Cd increase, Cr and Ni increase, as Cr increase, Cu and Ni increase, as Cu increase Ni increase and Pb increase Zn increase. Based on these results it was possible to predict and interpret similar contamination patterns in this study.

• Korean Journal of Environmental Agriculture
• /
• v.31 no.2
• /
• pp.157-163
• /
• 2012

BACKGROUND: For the safety of imported agricultural products, the study was conducted to develop the analytical method of unregistered pesticides in domestic. The analytical method of 6 pesticides, chlorthal-dimethyl, clomeprop, diflufenican, hexachlorobenzene, picolinafen, and propyzamide, for a fast multi-residue analysis were established for two different type crops, orange and brown rice by GC-ECD and confirmed by mass spectrometry. METHODS AND RESULTS: The analytical method was evaluated to limit of quantification, linearity and recoveries. The crop samples were extracted with acetonitrile and performed cleanup by liquid-liquid partition and Florisil SPE to remove co-extracted matrix. The extracted samples were analyzed by GC-ECD with good sensitivity and selectivity of the method. The limits of quantification (LOQ) range of the method with S/N ratio of 10 was 0.02~0.05 mg/kg for orange and brown rice. The linearity for targeted pesticides were $R^2$ >0.999 at the levels ranged from 0.05 to 10.0 mg/kg. The average recoveries ranged from 74.4% to 110.3% with the percentage of coefficient variation in the range 0.2~8.8% at two different spiking levels (0.02 mg/kg and 0.2 mg/kg, 0.05 mg/kg and 0.5 mg/kg) in brown rice. And the average recoveries ranged from 77.8% to 118.4% with the percentage of coefficient variation in the range 0.2~6.6% at two different spiking levels (0.02 mg/kg and 0.2 mg/kg, 0.05 mg/kg and 0.5 mg/kg) in orange. Final determination was by gas chromatography/mass spectrometry/selected ion monitoring (GC/MS/SIM) to identify the targeted pesticides. CONCLUSION: As a result, this developed analytical method can be used as an official method for imported agricultural products.

• The Korean Journal of Mycology
• /
• v.41 no.2
• /
• pp.57-66
• /
• 2013

The mushrooms collected at seven areas of Mt. Chiak in 2002 and 2003 were classified to analyse the distribution and species diversity. Frequency (number of mushroom : N), number of species (S), relative species density (RSD), similarity index (C), richness index (R1), variety index (V1), evenness index (E2), and dominance index(D1) were investigated. Total N and S was 143 and 84, respectively. The RSD was 0.179 ~ 0.226 of the 7 areas. The yearly C of the total area (0.213) was 8.2%. more higher than the average C of 7 areas (0.131). The order in the coefficient of variation (CV) of the indicator for 7 areas was N (10.5%) > D1 (9.2%) > V1 (8.9%) > S (8.5%) > R1 (7.4%) > E2 (2.2%). The average R1 of the 7 areas was 5.36 with the range from 4.85 to 6.01, and 16.72 for the total area. The average V1 of the 7 areas was 16.24 with the range from 14.44 to 18.66, and 68.82 for the total area. The average E2 of the 7 areas was 0.95 with the range from 0.926 to 0.982, and 0.819 for the total area. The average D1 of the 7 areas was 0.071 with the range from 0.055 to 0.073, and 0.081 for the total area. The correlation between N and 5 kinds of diversity indicator (S, R1, V1, E2, D) was not statistically significant, but the correlation between R1, E2 and D1 was statistically significant each other.

• Korean Journal of Environmental Agriculture
• /
• v.40 no.2
• /
• pp.134-141
• /
• 2021

BACKGROUND: The analytical method was established for determination of fungicide chinomethionat in several animal commodities using gas chromatography (GC) coupled with electron capture detector (ECD). METHODS AND RESULTS: In order to verify the applicability, the method was optimized for determining chinomethonat in various livestock products including beef, pork, chicken, milk and egg. Chinomethionat residual was extracted using acetone/dichloromethane(9/1, v/v) with magnesium sulfate and sodium chloride (salting outassociated liquid-liquid extraction). The extract was diluted by direct partitioning into dichloromethane to remove polar co-extractives in the aqueous phase. The extract was finally purified with optimized silica gel 10 g. CONCLUSION: The method limit of quantitation (MLOQ) was 0.02 mg/kg, which was in accordance with the maximum residue level (MRL) of chinomathionate as 0.05 mg/kg in livestock product. Recovery tests were carried out at two levels of concentration (MLOQ, 10 MLOQ) and resulted in good recoveries (84.8~103.0%). Reproducibilities were obtained (Coefficient of variation <5.2%), and the linearity of calibration curves were reasonable (r²>0.995) in the range of 0.01-0.2 ㎍/mL. This established analytical method was fully validated and could be useful for quantification of chinomathionat in animal commodities as official analytical method.

• Journal of Korean Society of Occupational and Environmental Hygiene
• /
• v.17 no.1
• /
• pp.13-20
• /
• 2007

This study was performed to investigate the concentrations of PM($PM_{10}$, $PM_{2.5}$, $PM_{1}$) and it's affecting factors in the subway from line 1 to line 8 in Seoul metropolitan area, from Sep. 1 to 30, 2005. PM concentrations were measured at the entrances and centers in subway passenger cabins by a light scattering equipment. And the affecting factors to PM were estimated based on the number of passenger, door open and close and running area etc. The geometric means of $PM_{10}$, $PM_{2.5}$ and $PM_{1}$ concentration in Seoul subway passenger cabins were $214{\mu}g/m^3$, $86.6{\mu}g/m^3$ and $27.0{\mu}g/m^3$, respectively. These mean concentrations in subway carriage were higher when it ran on an underground track than on a ground track. And running time(7AM-9AM, 11AM-13PM, 6PM-8PM) significantly influenced to the concentrations of $PM_{10}$, $PM_{2.5}$ and $PM_{1}$. Daily profile of $PM_{10}$ and $PM_{2.5}$, $PM_{1}$ expressed as an 10 minutes average, showed similar variation pattern over day period. In correlation analysis, significant relations among $PM_{10}$, $PM_{2.5}$ and $PM_{1}$ were detected(p〈0.01). In particular, correlation coefficient between $PM_{10}$and $PM_{1}$ was highly significant(r=0.94). Further study is needed to identity the sources of PM in subway cabins and to compare pollutants concentration among subway lines.

• Korean Journal of Plant Resources
• /
• v.24 no.2
• /
• pp.195-199
• /
• 2011

Tomato (Lycopersicon esculentum M.) is one of the most important crops to the fresh vegetable market and the food processing industry. To evaluate genetic variation in tomato fruits, major characteristics such as soluble solids, acidity and carotenoid contents were analyzed for 771 genetic resource lines. Lines in red color was about 85% which is the largest one followed by peach color, yellow, green, orange, and black. The sweetness of juice ranged from 2.2 to 11.5% (in brix), the average being 5.6%. The acidity ranged from 0.124% to 1.665%, and the average was 0.881%. The lycopine contents was up to 80.4 ${\mu}g/g$, and 43.4 ${\mu}g/g$ in average. ${\beta}$-carotine ranged 1.8 to 48.8 ${\mu}g/g$ and it average was 10.8 ${\mu}g/g$. Statistical analysis indicates that there is coefficient of correlation between acidity and sweetness, acidity and pH, pH and lycopine, lycopine and ${\beta}$-carotine. It is expected that the result of this study can be used for breeding more competitive species with respect to contents in sugar or functional chemicals from the selected characteristic species.