• The Journal of Engineering Geology
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• v.3 no.1
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• pp.21-37
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• 1993

In order to investigate the correlation of sedimentary rock properties. specific gravity, porosity, water content, sonic wave velodty, and point4oad strength index of core samples of limestones, sandstones and shales were measured. The relationships between density and velocity show $V_p=16300d-38719.3,{\;}V_s1896.4d-29225.1$ of regression equation for sandstones and $Vp=4085d-10264.8,{\;}V_s=3519d-7841.3$ for shales and <$Vp=4085d^2-20747d+303,{\;}V_s=3899d^2-21442d+318$ for limestones. Seismic wave velocity of shales which have high density is lower than that of sandstones, and this seems to be an effect of bedding in shale. P-wave velocity and S-wave velocity of limestones, sandstones and shales show the linear relationships as a whole. The regression equations are respectively calculated V_s=0.26V_p+1041.6m/sec,{\;}V_s=0.43V_p+424.2m/sec,{\;}and{\;}Vs=0.51V_p+261.9m/sec$ and the correlation coefficients of the velocity show r= 0.86 in sandstones, r= 0.75 in limestones and r=0.86 in shales. According to the point4oad strength test for limestones, point4ord strength anisotropy was not so dear even though the specimens show generally the banded structure. Variations of dip angle of bedding whihin the range $30^{\circ}-60^{\circ}$ does not have much influence upon the diametral strength index and axial strength index. From the result of point load test, P-wave velocity increases with point4ord strength index but the regression equations are $V_p=98.5lI{s_d}+4082.1m/sec,{\;}V_p=106.41{s_a}+3954m/sec$ and their correlation coefficient is low.

• Nuclear Engineering and Technology
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• v.55 no.8
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• pp.2773-2784
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• 2023

It is essential to evaluate the blasting-enhanced permeability (BEP) feasibility of a low-permeability sandstone-type uranium deposit. In this work, the mineral composition, reservoir physical properties and rock mechanical properties of samples from sandstone-type uranium deposits were first measured. Then, the reformability evaluation method was established by the analytic hierarchy process-entropy weight method (AHP-EWM) and the fuzzy mathematics method. Finally, evaluation results were verified by the split Hopkinson Pressure Bar (SHPB) experiment and permeability test. Results show that medium sandstone, argillaceous sandstone and siltstone exhibit excellent reformability, followed by coarse sandstone and fine sandstone, while the reformability of sandy mudstone is poor and is not able to accept BEP reservoir stimulation. The permeability improvement and the distribution of damage fractures before and after the SHPB experiment confirm the correctness of evaluation results. This research provides a reformability evaluation method for the BEP of the low-permeability sandstone-type uranium deposit, which contributes to the selection of the appropriate regional and stratigraphic horizon of the BEP and the enhanced ISL of the low-permeability sandstone-type uranium deposit.

• Journal of the Korean Institute of Traditional Landscape Architecture
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• v.37 no.4
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• pp.11-31
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• 2019

Taking the painting, 「Landscape of the Jiuqu River in the Wuyi Mountain」 as the study object, which was produced in the middle of Qing Dinasty and collected by the British Library, this paper analyzes the scenery names recorded in the painting, and describes the landscape of the mountain, port and ships, architectural elements, civil elements, character, stone inscription and other scenery in the painting. The investigation results of the cultural landscape properties of each Gok are as follows: According to statistics, there are 28 architectural elements in the painting, including 7 pavilions (25%), 4 temples (14.3%), 3 Colleges and Taoist temple (10.7%), 2 Dowon(道院) and villages (7.1%); 29 civil elements, including 9 holes (31%), 6 Historical Sites (20.7%), 3 Stations(臺) (10.3%), 2 Ferries, 2 Bridges, and 2 Ponds (6.9%), 1 Garden, 1 Gate, 1 Mine(坑), 1 Well and 1 Remains(3.4%). These physical factors and civil factors are the important relics reflected the cultural landscape attributes of Wuyi-Gugok in the middle of the 18th century. Among the shape element in each Gok, the 1^st Gok have 12 shape elements(21.1%), the 5^th Gok 11(19.3%), the 4^th Gok 9(15.8%), the 9^th Gok 8(14%), the 3^rd Gok 7(12.3%), the 6^th Gok 4(7%), the 2^nd Gok 3(5.3%), the 7^th Gok 2(3.5%), and the 8^th Gok 1(2%). Through collation, it is found that the 1^st Gok, 5^th Gok and 4^th Gok have more prominent cultural landscape characteristics. In addition, according to the description of scenic spot types in 『Muisanji(武夷山志)』, there are 38 types of scenery description in the painting, of which, the three scenery of big rock, peak, small rock occupy the vast majority. This reflects the Danxia(丹霞) landform characteristics of Wuyi-Gugok. The cultural connotation of Wuyi Mountain expressed and contained in the painting is analyzed and interpreted, and it is found that the Jiuqu(九曲) River in the Wuyi Mountain has Neo-confucianism culture, Taoism culture, Buddhism culture, Tea culture and so on. In addition, among the 171 scenery names shown in the painting, there are altogether 7 stone inscriptions that are consistent with or have the same meaning as the rock inscriptions site, including 3 for inscriptions praising the landscape, 3 for philosophical inscription and 1 for auspicious language inscription, which is considered as the important basis for the mutual textuality between the pictures and the stone inscriptions.

• Journal of Korean Society of Forest Science
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• v.54 no.1
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• pp.25-35
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• 1981

Some physical and chemical properties of forest soils in Korea were analyzed for providing the reasonable management methods of forest lands, Among 375 soil series surveyed until 1979, 93 soil series of forest soils were classified and analyzed according to their characteristics. Firstly soil data were classified into 5 categories by weathered products and secondly were classified and analyzed by parent rocks. The results are as follows: 1) In forest soils characterized by weathered products volcanic ash soils were proved to be the most fertile and alluvial soils were turned out to be the most infertile soils. Residual soils on mountain and hill were mostly on the average in all kinds of soil properties analyzed except total soil depth. 2) Igneous rocks developed rather infertile soils containing large amount of organic matter and available $P_2O_5$ with relatively deep soil depth and strong acidity. On the other hand sedimentary rocks produced rather shallow soils containing small amount of organic matter and available $P_2O_5$ but they were relatively fertile with weak acidity. 3) Among igneous rocks basalt and trachyte produced very fertile soils and granite and andesite produced slightly infertile soils. 4) Among sedimentary rocks limestone soils had high fertility neutral in acidity but low amount of available $P_2O_5$ 6) Alluvial sand produced generally very infertile soils with great soil depth comparing with the arable alluvial land with high fertility.

• Resources Recycling
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• v.17 no.6
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• pp.62-67
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• 2008

Oil shale is a sedimentary rock that contains organic compounds called kerogen that are released as petroleum-like liquids by retorting. In order to evalute oil shale as alternative oil resources, the physical properties of oil shale samples from US and Russia were investigated and Fischer assays were carried out. Thermogravimetric analysis shows that thermal degradation of oil shale consisted of two stage processes, with hydrocarbon release from kerogen followed by $CO_2$ release by carbonate decomposition. Organic compounds in oil shale have an high hydrogen/carbon ratio, and therefore liquid hydrocarbons could be obtained easily. Shale oil yields from Russian and US oil shales by Fischer assay were 12.7% and 18.5%, respectively. The density and boiling point of shale oils are higher than that of Middle East crude oil, indicating that further upgrading processes are necessary for refinery. On the other hands, sulfur contents are relatively low, and the amounts of Vanadium and Nickel are extremely small in shale oil. It was found that paraffins were rich in US shale oil while main components of Russian shale oil were oxygenated hydrocarbons.

• Journal of Physiology & Pathology in Korean Medicine
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• v.16 no.2
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• pp.365-372
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• 2002

The mineral medicines mean a sort of mineral or rock for medical treatment and natural material using their chemical components and physical properties. In this study, it was apprehended the mineralogical characteristics of As-bearing group mineral medicines. The extraction test is an vitro test system for predicting the bioavailability of the major and minor elements from mineral medicines and incorporates gastrointestinal tract parameters representative of a human(including stomach and small intestinal pH, stomach mixing time and velocity). The results of the extraction test are used for reaction path modeling in human body. Reaction path modeling in human body can predict digestion with gastric juice as well as bioavailability, speciation. Also, it can predict accumulation of arsenic as pH condition. As the results of the extraction test for digestion, the amounts of Fe extraction was the highest, followed by As, Ca, Ni. In addition, as the results of the reaction path modeling between arsenic compounds and gastric juice using thermodynamic data, when absorbed, major species are followed by H₃As₃S/sub 6/(aq), As₃S/sub 6/ (aq), AsO/sup +/, H₂As₃S/sup 6-/, H₂AsO/sup 3-/, HAs₃S6/sup 2-/, HAsO/sub 3//sup 2-/ and AsO/sub 3//sup 3-/. Specifically the concentration of H₃As₃S/sub 6/(aq) is the highest. As pH increases, the concentration of H₂AsO/sup 3-/, HAsO/sub 3//sup 2-/, HAsO/sub 3//sup 3-/, HAs₃S/sub 6//sup 2-/, H₂As₃S/sup 6-/, and H₃As₃S/sub 6/ increases, whereas the concentration of H₃As₃S/sub 6/ and AsO/sup +/ decreases. On the results of this study, it is able to find out effective and toxic components of poisonous arsenic group of mineral medicines and expected to be widely used for the development of new medicines.

• Geophysics and Geophysical Exploration
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• v.10 no.1
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• pp.1-18
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• 2007

Non-linear elastic wavefield inversion is a powerful method for estimating elastic parameters for physical constraints that determine subsurface rock and properties. Here, I introduce six elastic-wave velocity models by reconstructing elastic-wave velocity variations from real data and a 2D elastic-wave velocity model. Reflection seismic data information is often decoupled into short and long wavelength components. The local search method has difficulty in estimating the longer wavelength velocity if the starting model is far from the true model, and source frequencies are then changed from lower to higher bands (as in the 'frequency-cascade scheme') to estimate model elastic parameters. Elastic parameters are inverted at each inversion step ('simultaneous mode') with a starting model of linear P- and S-wave velocity trends with depth. Elastic parameters are also derived by inversion in three other modes - using a P- and S-wave velocity basis $('V_P\;V_S\;mode')$; P-impedance and Poisson's ratio basis $('I_P\;Poisson\;mode')$; and P- and S-impedance $('I_P\;I_S\;mode')$. Density values are updated at each elastic inversion step under three assumptions in each mode. By evaluating the accuracy of the inversion for each parameter set for elastic models, it can be concluded that there is no specific difference between the inversion results for the $V_P\;V_S$ mode and the $I_P$ Poisson mode. The same conclusion is expected for the $I_P\;I_S$ mode, too. This gives us a sound basis for full wavelength elastic wavefield inversion.

• Korean Journal of Organic Agriculture
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• v.14 no.2
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• pp.205-217
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• 2006

This research was carried out to investigate the effects of some organic materials such as rice straw, compost, hairy vetch, phosphate rock, magnesium lime powder and ash in the organic paddy fields, and also to develope the new technique for better soil management using described materials. The results are as follows; Height and tiller of rice plants were higher in chemical fertilizer than rice straw or compost, however, those of rice plants in hairy vetch-rice cropping system reached to chemical fertilizer. The Eh value of soil has decreased consecutively since on 30th, May because of the rising of soil temperature by an increase in the activity of microbes. As a result of measuring yield and yield components, there is not significant difference between treatment. The application of organic materials enriched the contents of available phosphorus, exchangible potassium and calcium in soil, and, also improved the physical properties such as pore space rates and bulk density. From the viewpoint of soil management technology in organic paddy fields, the application of rice straw or organic compost might cause the decrease of yield compared with conventional cultivation system, chemical fertilizer, however, the application of hairy vetch residues of soil compensated for growth and yield as well as improved the physicochemical property. Therefore, it is assumed that the cultivation of hairy vetch for winter season can be one of the useful methods for organic farming system.

• Journal of Conservation Science
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• v.24
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• pp.1-11
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• 2008

The Unhyungung Water Container in the possession of the Seoul Museum of History in Korea is consisted of a calcareous marble developed laminated bedding and numerous argillaceous veinlets. This monument should need to conservation treatment because of black discoloration and seriously numerous cracks. Vertical and horizontal cracks in the monument are developed following stratification and argillaceous veinlets that are relatively low coherence between the rock materials. We have proved that the material inducing discoloration on the surface is carbon which is formed by deposited organic matters. As the result of the ultrasonic measurements, although highly surface weathering degree, the physical properties of the Unhyungung Water Container is confirmed slightly weathered state. The depths of cracks in the monument are calculated at maximum 60mm in some cracks completely penetrating into the wall and at minimum 9mm in the other crack. The cracks, developed following veinlet, are revealed that there penetrate from an outer wall to an inside wall for the monument. And most depths of cracks, developed following stratification, are calculated 20 to 30mm. This result will offer a significant data for conservation of the Unhyungung Water Container.

• Economic and Environmental Geology
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• v.46 no.2
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• pp.199-206
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• 2013

The Daehyun gold-silver deposit consists of two hydrothermal quartz veins that fill NE-trending fractures in the Cambro-Ordovician calcitic marble. I have sampled wallrock, hydrothermaly-altered rock and gold-silver ore vein to study the element dispersion and element gain/loss during wallrock alteration. The hydrothermal alteration doesn't remarkably recognized at this deposit and consists of mainly calcite, dolomite, quartz and minor epidote. The ore minerals composed of arsenopyrite, pyrrhotite, pyrite, sphalerite, stannite, chalcopyrite, galena, electrum, native bismuth and silver-bearing mineral. Based on analyzed data, the chemical composition of wallrock consists of mainly $SiO_2$, CaO, $CO_2$ with amounts of $Al_2O_3$, $Fe_2O_3(T)$ and MgO. The contents of $SiO_2$, $Fe_2O_3(T)$, MgO, CaO and $CO_2$ vary significantly with distance from ore vein. The element dispersion doesn't remarkably recognized during wallrock alteration and only occurs near the ore vein margin because of physical and chemical properties of wallrock. Remarkable gain elements during wallrock alteration are $Fe_2O_3(T)$, total S, Ag, As, Bi, Cd, Cu, Ni, Pb, Sb, Sn, W and Zn. Remarkable loss elements are $SiO_2$, MnO, MgO, CaO. $CO_2$ and Sr. Therefore, Our result may be used when geochemical exploration carry out at deposits hosted calcitic marble in the Hwanggangri metallogenic district.