• Journal of The Geomorphological Association of Korea
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• v.19 no.4
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• pp.123-137
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• 2012

Reddish superficial materials in southern area of Korean Peninsula have been defined as lateritic red soil in Korea. In A-CN-K ternary plots, CaO and $Na_2O$ show similar linear distribution along a A-K line to kaolinite profile and laterite in southern Spain and Cameroon, respectively, and it means strong alteration. But $K_2O$ is weak alteration, plotting between muscovite and illite zone. Granitic reddish weathering mantles in study area show bulk distribution in center when plotted in A-CNK-Fm space, in contrast to laterite in Cameroon, plotting linearly in the middle along a A-FM line. Therefore, alteration of reddish saprolites in Southern Korea have not progressed as much as laterite. To define Reddish saprolite in southern Korean Peninsula as a lateritic red soil, more many studies are necessary.

• Journal of The Geomorphological Association of Korea
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• v.19 no.1
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• pp.57-68
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• 2012

Red saprolites are appeared in granitic hills in Naju, Southern Korean Peninsula. These red saprolites were analyzed for their geochemistry, including CIA, A-CN-K and A-CNK-FM ternary plots, to understand the chemical weathering trend and rubefaction of the saprolites. These saprolites were compared with kaolinitic saprolites of Guadalquivir Basin in Spain formed under paleo-humid tropical conditions. Chemical Index of Alteration(CIA) value for Naju in Korea is 80, and 87 in Guadalquivir, suggesting moderate and strong weathering in both. Relative to kaolinitic saprolite of Guadalquivir in Spain, red saprolites in Naju are commonly weak loss of CaO, $Na_2O$, especially in $K_2O$. The A-CNK-FM ternary plots of Naju saprolites relative to Kaolinitic saprolites of Guadalquivir shows weak chemical alteration owing to slow removal of $K_2O$, but high mafic constituents, $Fe_2O_3$ and MgO, for most of the samples. In the saprolites of Naju, mafic oxides, $Fe_2O_3$ and MgO, become enriched because of the fast and massive removal of CaO, $Na_2O$ and $K_2O$ relative to other elements, resulting in rubefaction of the surface layer of the saprolites, so more redness than kaolinitic saprolites of Guadalquivir. It is found that the rubefaction of the saprolites is not necessarily proportional to chemical weathering intensity.

• Journal of the Korean Geographical Society
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• v.39 no.3
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• pp.425-443
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• 2004

Fluvial terraces is poorly developed along Bukhan River in Central Korea. Altitude from riverbed of T1 terraces are 18-29m, T2 terraces 2539m, respectively. Rubification index of T2 is 0.66, T1 is 0.54, and thickness of gravel weathering rind on gneiss of T2 are 14.0mm, granites of T2 are $\infty$, gneiss of T1 are 5.0mm and granites of T2 are 8.0mm, because weathering in deposits of T2 terraces, older than T1, is severer than T1 terraces. Since deposits in T2 have more active and longer weathering than T1, SiO$_2$/Al$_2$O$_3$ is 3.32 in T2 and 4.06 in T1, and SiO$_2$/R$_2$O$_3$ is 2.64 in T2 and 3.19 in T1. CIA(Chemical Index of Alteration) is 87.85％ in T2 and 85.88％ in T1. Kaolinite and halloysite are founded in deposits of T2 indicating high weathering, and are founded gibbsite made tv eluviation of kaolinite. However, deposits of T1 have no kaolinite, and are found plagioclase, weak mineral in weathering process. Comparing to previous researches by estimated age as altitude from riverbed, rubification index, thickness of gravel weathering rind, element contents and mineral composition, forming age of T2 terraces in Bukhan River are estimated in marine oxygen isotope stage 6 (130-190ka), and T1 terraces are marine oxygen isotope stage 4(59-74ka).

• Journal of the Korean Geographical Society
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• v.47 no.3
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• pp.315-327
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• 2012

Red saprolites are appeared in granitic hills in Yeongam, Southern Korean Peninsula. These red saprolites were analyzed for their geochemistry, including CIA, A-CN-K and A-CNK-FM ternary plots, to understand the chemical weathering trend and rubefaction of the saprolites. These saprolites were compared with laterite profiles in Cameroon formed under humid tropical conditions. The red saprolites in Yeongam show commonly massive loss of CaO, $Na_2O$, but $K_2O$ is being slow. The red saprolites in Yeongam relative to laterite and kaolinite profiles of Cameroon and Spain show weak chemical alteration owing to slow removal of $K_2O$, but high mafic constituents, $Fe_2O_3$ and MgO, for most of the samples. In the saprolites of Yeongam, mafic oxides become enriched because of the fast and massive removal of alkali constituents, such as CaO, $Na_2O$ and $K_2O$, relative to other elements, resulting in rubefaction of the saprolites. It is found that the rubefaction of the saprolites is not necessarily proportional to chemical weathering intensity.

• Journal of the Korean Geographical Society
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• v.39 no.1
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• pp.27-44
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• 2004

Upper reach of Soyang River at the northernmost area around Taebaek Mountains in South korea is profitable area to understand paleo-environment during the Quaternary such as tectonic process and climate change in the Korean Peninsula. This study explained paleo-environment affect to channel development by geomorphic distribution and characteristics of terrace surfaces, and analysis of deposits at 58 fluvial terraces in upper reach of Soyang River. Fluvial terraces were classified from T1 to T6. Most terraces are distributed on the point bar in meandering channel and one side along river valley. Terraces tend to decrease in number and superficial dissection rate to be higher and channel slope to be steeper if it takes long time from T1 to 6. The paleo-channel of Soyang River is supposed to be stronger meandering in period of T2 than T3. The weathering rind of gravel is generally thicker in older terrace, however, differs by contents of water and air in deposits. Based on the data of stratigraphy, grain size analysis, pollen analysis and rubification index in deposit, formation age of T5 terrace in Soyang River are estimated in MIS(Marine Oxygen Isotope Stage) 10, and T2 terrace are estimated in MIS 6.

• Korean Journal of Remote Sensing
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• v.35 no.3
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• pp.375-387
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• 2019

The use of drone-based hyperspectral image offers considerable advantages in high resolution remote sensing applications. The primary objective of this study was to select the optimal bands based on hyperspectral image for the estimation yield of the chinese cabbage. The hyperspectral narrow bands were acquired over 403.36 to 995.19 nm using a 3.97 nm wide, 150 bands, drone-based hyperspectral imaging sensor. Fresh weight data were obtained from 2,031 sample for each field survey. Normalized difference vegetation indices were computed using red, red-edge and near-infrared bands and their relationship with quantitative each fresh weights were established and compared. As a result, predominant proportion of fresh weights are best estimated using data from three narrow bands, in order of importance, centered around 697.29 nm (red band), 717.15 nm (red-edge band) and 808.51 nm (near-infrared band). The study determined three spectral bands that provide optimal chinese cabbage productivity in the visible and near-infrared portion of the spectrum.

• Journal of Astronomy and Space Sciences
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• v.21 no.1
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• pp.1-10
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• 2004

We present BV CCD photometry of metal-rich globular cluster M71. Based on our color-magnitude diagram (CMD), we derive the distance to M71 using a sample of Hipparcos subdwarfs of similar metallicity. Our distance modulus is (m - M)v = 13.46(${\pm}0.17$. CMD comparison was also made between M71 and 47 Tuc. We confirm that there exists a significant age differonce(> 2 billion years) in spite of their Similarity in metallicity.

• Journal of Bio-Environment Control
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• v.9 no.4
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• pp.223-229
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• 2000

This study was conducted to analyze the opto-electric characteristics of light-emitting diodes(LED) designed for growth and morphogenesis control of transplant and to quantify the photon flux emittig from LED using a quantum sensor spectroradiometer. Difference in photon flux for blue and red LED between measured by a quantum sensor and measured by a spectroradiometer and numerically integrated was not observed. This result implies a spectroradiometer can be applied to quantify the photon flux emitting from far-red LED, which can not be measured using a quantum sensor. Since photon flux increases in proportion to wavelength, photon flux of LED modules arranged for red and far-red increased in proportion to wavelength, photon flux of LED modules arranged for red and rar-red increased gradually as the number of LED stick emitting far-red in LEd modules increased. Illumination of LED modules arranged for red and far-red decreased as the number of LED stick emitting far-red in LED modules increased. There was no difference in irradiance between LED modules arranged for red and far-red.

• Korean Journal of Remote Sensing
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• v.38 no.5_1
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• pp.523-533
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• 2022

This paper presents a two-stage spatio-spectral fusion method (2SSFM) based on area-to-point regression kriging (ATPRK) to enhance spatial and spectral resolutions using multi-sensor satellite images with complementary spatial and spectral resolutions. 2SSFM combines ATPRK and random forest regression to predict spectral bands at high spatial resolution from multi-sensor satellite images. In the first stage, ATPRK-based spatial down scaling is performed to reduce the differences in spatial resolution between multi-sensor satellite images. In the second stage, regression modeling using random forest is then applied to quantify the relationship of spectral bands between multi-sensor satellite images. The prediction performance of 2SSFM was evaluated through a case study of the generation of red-edge and short-wave infrared bands. The red-edge and short-wave infrared bands of PlanetScope images were predicted from Sentinel-2 images using 2SSFM. From the case study, 2SSFM could generate red-edge and short-wave infrared bands with improved spatial resolution and similar spectral patterns to the actual spectral bands, which confirms the feasibility of 2SSFM for the generation of spectral bands not provided in high spatial resolution satellite images. Thus, 2SSFM can be applied to generate various spectral indices using the predicted spectral bands that are actually unavailable but effective for environmental monitoring.

• Korean Journal of Soil Science and Fertilizer
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• v.19 no.4
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• pp.275-282
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• 1986

A series of studies on the properties of clayey terrace soils distributed at the inland (Yeongcheon) and coastal (Yeongjil) regions in Yeongnam district was carried out. On the base of the facts found and already reported about the macro morphological features as well as on pedological characters in micro scale, physicochemical properties, mineralogical characteristics etc., the present study dealt with soil genesis and tried to classify the soils for reasonable use and managements. 1. Although the both regions belonged to "Mesic" soil temperature regime and "red and yellow earths" areas of "Thornthwaite" pedo-climatic diagram, climatic indices as a soil forming factor indicate that the coastal Yeongil had milder than the inland Yeongcheon. 2. All the terrace soils had developed soil profiles with an "Argrllic B". Upyeong soils in Yeongil region had "Argillans" even in the "II B horizons" that possibly be "Paleo-argillic". 3. The bisequum profiles of Bancheon in Yeongcheon and Upyeong in Yeongil revealed that they were developed on Late Mesozoic shale and on semiconsolidated Tertiary deposits respectively, therefore the overlying clayey terrace deposits were assumed to be originated from the Early Quaternary deposits, Diluvium. 4. To supplement the Soil Taxonomy of USDA, the terrace soils with different degrees of gleyzation were classified as follows; Deogpyeong and Hwadong soils which have less than 50cm of paddified gley horizons (redness less than 0.5) in the upper part of the profiles by artificial surface irrigation, tentatively classified into "Anthrepiaquic Hapludalfs" and the Geugrag soils that have more than 50cm of paddified gley horizons within 1.2m of the profiles, into "Anthr-aquic Ochraqualfs" while the Upyeong soils that had greyish mottles in subsoils by natural ground water remain as an "Aquic Hapludalfs" the same as present. The Bancheon soils with free mottles are into "Typic Hapludalfs" as used at present.