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Analysis of Optimal Locations for Resource-Development Plants in the Arctic Permafrost Considering Surface Displacement: A Case Study of Oil Sands Plants in the Athabasca Region, Canada (지표변위를 고려한 북극 동토 지역의 자원개발 플랜트 건설 최적 입지 분석: 캐나다 Athabasca 지역의 오일샌드 플랜트 사례 연구)

  • Taewook Kim;YoungSeok Kim;Sewon Kim;Hyangsun Han
    • The Journal of Engineering Geology
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    • v.33 no.2
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    • pp.275-291
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    • 2023
  • Global warming has made the polar regions more accessible, leading to increased demand for the construction of new resource-development plants in oil-rich permafrost regions. The selection of locations of resource-development plants in permafrost regions should consider the surface displacement resulting from thawing and freezing of the active layer of permafrost. However, few studies have considered surface displacement in the selection of optimal locations of resource-development plants in permafrost region. In this study, Analytic Hierarchy Process (AHP) analysis using a range of geospatial information variables was performed to select optimal locations for the construction of oil-sands development plants in the permafrost region of southern Athabasca, Alberta, Canada, including consideration of surface displacement. The surface displacement velocity was estimated by applying the Small BAseline Subset Interferometric Synthetic Aperture Radar technique to time-series Advanced Land Observing Satellite Phased Array L-band Synthetic Aperture Radar images acquired from February 2007 to March 2011. ERA5 reanalysis data were used to generate geospatial data for air temperature, surface temperature, and soil temperature averaged for the period 2000~2010. Geospatial data for roads and railways provided by Statistics Canada and land cover maps distributed by the North American Commission for Environmental Cooperation were also used in the AHP analysis. The suitability of sites analyzed using land cover, surface displacement, and road accessibility as the three most important geospatial factors was validated using the locations of oil-sand plants built since 2010. The sensitivity of surface displacement to the determination of location suitability was found to be very high. We confirm that surface displacement should be considered in the selection of optimal locations for the construction of new resource-development plants in permafrost regions.

Jangdo(Small Ornamental Knives) manufacturing process and restoration research using Odong Inlay application (오동상감(烏銅象嵌)기법을 활용한 장도(粧刀)의 제작기술 및 복원연구)

  • Yun, Yong Hyun;Cho, Nam Chul;Jeong, Yeong Sang;Jang, Chu Nam
    • Korean Journal of Heritage: History & Science
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    • v.49 no.2
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    • pp.172-189
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    • 2016
  • In this research, literature research on the Odong material, mixture ratio, casting method and casting facility was conducted on contemporary documents, such as Cheongong Geamul. Also, a long sword was produced using the Odong inlay technique. The sword reproduction steps were as follows; Odong alloying, silver soldering alloying, Odong plate and Silver plate production, hilt and sheath production, metal frame and decorative elements, such as a Dugup (metal frame), production, Odong inlay assembly and final assembly. For the Odong alloy production, the mixture ratio of the true Odong, which has copper and gold ratio of 20:1, was used. This is traditional ratio for high quality product according to $17^{th}$ century metallurgy instruction manual. The silver soldering alloy was produced with silver and brass(Cu 7 : Zn 3) ratio of 5:1 for inlay purpose and 5:2 ratio for simple welding purpose. The true Odong alloy laminated with silver plate was used to produce hilt and sheath. The alloy went through annealing and forging steps to make it into 0.6 mm thick plate and its backing layer, which is a silver plate, had the matching thickness. After the two plates were adhered, the laminated plate went through annealing, forging, engraving, silver inlaying, shaping, silver welding, finishing and polishing steps. During the Odong colouring process, its red surface turns black by induced corrosion and different hues can be achieved depending on its quality. To accomplish the silver inlay Odong techniques, a Hanji saturated with thirty day old urine is wrapped around a hilt and sheath material, then it is left at warm room temperature for two to three hours. The Odong's surface will turn black when silver inlay remains unchanged. Various scientific analysis were conducted to study composition of recreated Odong panel, silver soldering, silver plate and the colouring agent on Odong's surface. The recreated Odong had average out at Cu 95.57 wt% Au 4.16wt% and Cu 98.04 wt% Au 1.95wt%, when documented ratio in the old record is Cu 95wt% and Au 5wt%. The recreated Odong was prone to surface breakage during manufacturing process unlike material made with composition ratio written in the old record. On the silver plate of the silver and Odong laminate, 100wt% Ag was detected and between the two layers Cu, Ag and Au were detected. This proves that the adhesion between the two layers was successfully achieved. The silver soldering had varied composition of Ag depending on the location. This shows uneven composition of the silver welding. A large quantities of S, that was not initially present, was detected on the surface of the black Odong. This indicates that presence of S has influence on Odong colour. Additional study on the chromaticity, additional chemical compounds and its restoration are needed for the further understanding of the origin of Odong colour. The result of Odong alloy testing and recreation, Odong silver inlay long sword production, scientific analysis of the Odong black colouring agent will form an important foundation of knowledge for conservation of Odong artifact.

Comparative Studies on the Lipid Composition in Varieties of Dent Corn (마치종(馬齒種)옥수수의 품종별(品種別) 지질조성(脂質組成)의 비교(比較))

  • Ahn, Doo-Hee;Ha, Bong-Seuk
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.16 no.4
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    • pp.350-363
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    • 1987
  • This study dealt with the comparison of the individual lipid component and fatty acid composition in the six varieties of dent corn, Zea mays Indentata. The fatty acid and sterol compositions of the total lipid were analyzed by gas liquid chromatography. The total lipid was also fractionated into three lipid classes namely neutral, glyco and phospolipid by the methods of silicic acid column chromatography. The lipid componets of lipid-classes were estimated by thin layer chromatography and TLC-scanner. The contents of total lipid in six varieties of Cdent corn were $3.7{\sim}5.3%$. Total lipid were mainly Composed of triglyceride$(69.8{\sim}75.7%)$ free fatty acid$(13.0{\sim}17.9%)$, lanosterol$(4.8{\sim}6.0%)$. hydrocarbon & esterified sterol$(3.5{\sim}6.0%)$, and polar lipid & pigment$(2.7{\sim}5.9%)$. The contents of triglycerde in $Chech'{\breve{o}}nok$ and Hwangok No.3 were slightly higher then other varieties. The major fatty acid In total lipid from six varieties of dent corn were chiefly consisted of linoleic$(46.0{\sim}61.4%)$, oleic$(21.9{\sim}29.9%)$ and palmitic acid$(10.9{\sim}16.7%)$. Particularly the content of linoleic acid in $Chech'{\breve{o}}nok$ was higher but oleic and palmitic acid in $Chech'{\breve{o}}nok$ were less than other varieties. The compositions of 4-desmethylsterol were mainly composed of siterol $(44.0{\sim}63.2%)$, campestetel$(11.6{\sim}15.5%)$ and stigmasterol$(5.6{\sim}9.1%)$. The content of sitosterol in Chinjuok was higher than other varieties and isofucosterol was detected only in Chinjuok. The compositions of 4-monomethlysterol were mainly composed of obtusifoliol$(17.7{\sim}37.6%)$, gramisterol$(15.0{\sim}27.0%)$ and citrostadienol$(9.1{\sim}17.3%)$. The contents of obtusifoliol and citrostadienol in Kwangok and Chinjuok were less than other varieties. The contents of fractionated neural lipid in Suwon No.19. Kwangok, $Hoengs{\breve{o}}ngok$ and Chinjuok$(90.3{\sim}97.1%)$ were higher than those of $Chech'{\breve{o}}nok$ and Hwangok No.3$(85.5{\sim}86.1%)$. Neutral lipid were mainly composed of triglyceride$(24.7{\sim}80.0%)$, lanosterol$(6.2{\sim}20.2%)$, Cholesterol$(1.0{\sim}50.6%)$, free fatty acid$(4.4{\sim}8.9%)$ and esterified sterol$(1.5{\sim}15.9%)$. The major fatty acid in neutral lipid from six varieties of dent corn were chiefly consisted of linoleic$(26.2{\sim}55.4%)$ oleic$(22.7{\sim}39.1%)$ and palmitic acid$(11.4{\sim}41.6%)$. Particularly the contents of linoleic acid Suwon No.19 and $Chech'{\breve{o}}nok$ were higher but palmtic acid in Suwon No.19 and $Chech'{\breve{o}}nok$ were less tan other varieties. Glycolipd were mainly composed of nlonoglycosflsterol $(17.5{\sim}56.4%)$, monoglycosylce-ramide $(8.2{\sim}25.9%)$ and monoglycoslydiacylglycerol$(12.4{\sim}22.2%)$. The contents of mono-g1ycosrlceramide and monoglycosrlsterol in Chinjuok. Were higher than other varieties. The major fatty acid in glycolipid from six varieties of dent corn were chiefly consisted$(14.6{\sim}39.3%)$, palmitic$(20.0{\sim}26.1%)$, linoleic$(3.6{\sim}26.9%)$ and heptadecanoic acid $(3.3{\sim}24.7%)$. Particutarly the cantents of oleic acid in Chinjuok and heptadecanoic acid in $Chech'{\breve{o}}nok$ were higher than other varieties. Phospholipid were mainly composed of phosphatidyllnositol$(30.9{\sim}86.4%)$ and phosphatidylcholine$(4.5{\sim}22.0%)$. The contents of phosphatidrlinositol in $Hoengs{\breve{o}}ngok$ and Hwanngok No. 3 were less than other varieties. The major fatty acid in phospolipid from six varieties of dent corn chiefly consisted of patmitic$(37.2{\sim}61.6%)$ heptadecanoic$(9.2{\sim}31.8%)$ and oleic acid$(4.3{\sim}17.2%)$. Particuiarlr the content of oleic acid in $Hoengs{\breve{o}}ngok$ was higher but heptadccanoic acid in $Hoengs{\breve{o}}ngok$ was less than othcr varieties.

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Studies on the Determination Method of Natural Sweeteners in Foods - Licorice Extract and Erythritol (식품 중 감초추출물 및 에리스리톨 분석법에 관한 연구)

  • Hong Ki-Hyoung;Lee Tal-Soo;Jang Yaung-Mi;Park Sung-Kwan;Park Sung-Kug;Kwon Yong-Kwan;Jang Sun-Yaung;Han Ynun-Jeong;Won Hye-Jin;Hwang Hye-Shin;Kim Byung-Sub;Kim Eun-Jung;Kim Myung-Chul
    • Journal of Food Hygiene and Safety
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    • v.20 no.4
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    • pp.258-266
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    • 2005
  • Licorice Extract and Erythritol, food additives used in korea, are widely used in foods as sweetener. Its application for use in food is regulated by the standard and specification for food additives but official analytical method far determination of these sweetener in food has not been established. Accordingly, we has been carried out to set up analytical method of the glycyrrhizic acid in several foods by the way of thin layer chromatography and high performance liquid chromatography glycyrrhizic acid is qualitative anaylsis technique consists of clean-up with a sep-pak $C_{18}$ cartridge, separation of the sweeteners by Silica gel 60 F254 TLC plate using 1-butanol:4Nammonia solution:ethanol (50:20:10) as mobile solvent. Also, the quantitative analysis for glycyrrhizic acid, was performed using Capcell prk $C_{18}$ column at wavelength 254nm and DW:Acetonitrile (62:38 (pH2.5)) as mobile phase. and we has been carried out to set up analytical method of the erythritol in several foods by the way of high performance liquid chromatography. erythritol is qualitative anaylsis technique consists of clean-up with a DW and hexane. The quantitative analysis for erythritol, was performed using Asahipak NH2P-50 column, Rl and DW:Acetonitrile (25:75) as mobile phase. The glycyrrhizic acid results determined as glycyrrhizic acid in 105 items were as follows; N.D$\∼$48.7ppm for 18 items in soy sauce, N.D$\∼$5.3ppm for 12 items in sauce, N.D$\∼$988.93ppm for 15 items in health food, N.D$\∼$180.7ppm for 26 items in beverages, N.D$\∼$2.6ppm for 8 items in alcoholic beverages repectively and ND for 63 items in the ethers. The erythritol results determined as erythritol in 52 items were as follows; N.D$\∼$155.6ppm for 13 items in gm, N.D$\∼$398.1ppm for 12 items in health foods repectively and ND for 45 items in the others.

The Morphology, Physical and Chemical Characteristics of the Red-Yellow Soils in Korea (우리나라 전토양(田土壤)의 특성(特性) (저구릉(低丘陵), 산록(山麓) 및 대지(臺地)에 분포(分布)된 적황색토(赤黃色土)를 중심(中心)으로))

  • Shin, Yong Hwa
    • Korean Journal of Soil Science and Fertilizer
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    • v.6 no.1
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    • pp.35-52
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    • 1973
  • Red Yellow Soils occur very commonly in Korea and constitute the important upland soils of the country which are either presently being cultivated or are suitable for reclaiming and cultivating. These soils are distributed on rolling, moutain foot slopes, and terraces in the southern and western parts of the central districts of Korea, and are derived from granite, granite gneiss, old alluvium and locally from limestone and shale. This report is a summary of the morphology, physical and chemical characteristics of Red Yellow Soils. The data obtained from detailed soil surveys since 1964 are summarized as follows. 1. Red-Yellows Soils have an A, Bt, C profile. The A horizon is dark colored coarse loamy or fine loamy with the thin layer of organic matter. The B horizon is dominantly strong brown, reddish brown or yellowish red, clayey or fine loamy with clay cutans on the soil peds. The C horizon varies with parent materials, and is coarser texture and has a less developed structure than the Bt horizon. Soil depth, varied with relief and parent materials, is predominantly around 100cm. 2. In the physical characteristics, the clay content of surface soil is 18 to 35 percent, and of subsoil is 30 to 90 percent nearly two times higher than the surface soil. Bulk density is 1.2 to 1.3 in the surface soil and 1.3 to 1.5 in the subsoil. The range of 3-phase is mostly narrow with 45 to 50 percent in solid phase, 30 to 45 percent in liquid one, and 5 to 25 percent in gaseous state in the surface soil; and 50 to 60 solid, 35 to 45 percent liquid and less than 15 percent gaseous in the subsoil. Available soil moisture capacity ranges from 10 to 23 percent in the surface soil, and 5 to 16 percent in the subsoil. 3. Chemically, soil reaction is neutral to alkaline in soils derived from limestone or old fluviomarine deposits, and acid to strong acid in other ones. The organic matter content of surface soil varying considerably with vegetation, erosion and cultivation, ranges from 1.0 to 5.0 percent. The cation exchange capacity is 5 to 40 me/100gr soil and closely related to the content of organic matter, clay and silt. Base saturation is low, on the whole, due to the leaching of extractable cations, but is high in soils derived from limestone with high content of lime and magnesium. 4. Most of these soils mainly contain halloysite (a part of kaolin minerals), vermiculite (weathered mica), and illite, including small amount of chlorite, gibbsite, hematite, quartz and feldspar. 5. Characteristically they are similar to Red Yellow Podzolic Soils and a part of Reddish Brown Lateritic Soils of the United States, and Red Yellow Soils of Japan. According to USDA 7th Approximation, they can be classified as Udu Its or Udalfs, and in FAO classification system to Acrisols, Luvisols, and Nitosols.

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Variation in Lipid Composition during the Growing Period of the Prawn I. Comparative Studies on the Flesh Lipid Composition of the Wild and Cultured Prawn (보리새우 성장중의 지질성분 변화에 관한 연구 1. 천연 및 양식산 보리새우의 근육 지질성분의 비교)

  • Ha Bong-Seuk;MATSUNO Takao;KATSUYAMA Masaaki
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.18 no.4
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    • pp.297-308
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    • 1985
  • Differences in lipid composition including fatty acid, lipid class, sterol and especially carotenoid between fleshes of wild and cultured prawn, Penaeus japonicus, were studied. Total lipids were extracted from the flesh during the spawning period and fractionated into two lipid classes of polar and nonpolar lipids by silicic acid column chromatography. The fatty acid composition of each lipid classes, total lipid (TL), nonpolar lipid (NL) and polar lipid (PL) were analyzed by gas liquid chromatography. The sterol and carotenoid composition of total lipids were determined by using thin layer chromatography, gas liquid chromatography and column chromatography using MgO-celite 545 and silicic acid-celite 545 as an absorbent, and by UV spectrophotometry. Total lipid contents of both fleshes from the wild and cultured prawn were about $2.0\%$ on average, but the content of the unsaponifiable matters in the cultured prawn (about $16.2\%$ in total lipid) showed a little higher than that of the wild prawn (about $13.9\%$ in total lipid) and the ratio of NL to PL in total lipid was 1:1.7. In the fatty acid composition of TL, the contents of $Cl_{16:0}\;and\;C_{20:3}$ fatty acids were higher in wild prawn than in cultured prawn, while the contents of $Cl_{18:1}\;and\;C_{20:5}$ fatty acids in cultured prawn were higher than those in wild prawn. The cultured prawn contained higher amounts of monoenoic acids and lower amounts of polyenoic acids than the wild prawn. In the fatty acid composition of NL, the wild prawn showed higher levels in $Cl_{18:0}\;and\;C_{20:1}$ fatty acid contents than the cultured prawn, while the cultured prawn contained much amout of $Cl_{16:0}\;and\;C_{18:1}$ fatty acids. On the other hand, the fatty acid composition of PL showed that $Cl_{16:1}\;and\;C_{17:1}$ fatty acid were higher in the wild prawn than in the cultured prawn, but in $Cl_{16:0}\;and\;C_{18:1}$ fatty acids, the levels were reversed. Consequently, the cultured prawn contained higher amount of monoenoic acids, and similar amounts of saturated acids and polyenoic acids to the wild prawn in NL. And the cultured prawn contained lower amount of monoenoic acids, and similar amounts of saturated acids and polyenoic acids to the wild prawn in PL. In sterol composition of both the wild and cultured prawn, the predominant sterol was cholesterol with the proportion of $78.7{\sim}88.9\%$ to the total sterol. In addition to the cholesterol, the other minor sterols such as 24-methylene cholesterol and sitosterol were detected. Total carotenoid content in flesh of the wild prawn was relatively higher than that of the cultured prawn marking 70 mg/100g of lipid in wild prawn and 40 mg/100 g of lipid in cultured prawn, respectively. The main carotenoids of the both prawns were astaxanthin($54.1{\sim}60.8%$), phoenicoxanthin ($16.5{sim}22.9%$),${\bata}-carotene\;(20.0{\sim}22.0%)$.

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Edge to Edge Model and Delay Performance Evaluation for Autonomous Driving (자율 주행을 위한 Edge to Edge 모델 및 지연 성능 평가)

  • Cho, Moon Ki;Bae, Kyoung Yul
    • Journal of Intelligence and Information Systems
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    • v.27 no.1
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    • pp.191-207
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    • 2021
  • Up to this day, mobile communications have evolved rapidly over the decades, mainly focusing on speed-up to meet the growing data demands of 2G to 5G. And with the start of the 5G era, efforts are being made to provide such various services to customers, as IoT, V2X, robots, artificial intelligence, augmented virtual reality, and smart cities, which are expected to change the environment of our lives and industries as a whole. In a bid to provide those services, on top of high speed data, reduced latency and reliability are critical for real-time services. Thus, 5G has paved the way for service delivery through maximum speed of 20Gbps, a delay of 1ms, and a connecting device of 106/㎢ In particular, in intelligent traffic control systems and services using various vehicle-based Vehicle to X (V2X), such as traffic control, in addition to high-speed data speed, reduction of delay and reliability for real-time services are very important. 5G communication uses high frequencies of 3.5Ghz and 28Ghz. These high-frequency waves can go with high-speed thanks to their straightness while their short wavelength and small diffraction angle limit their reach to distance and prevent them from penetrating walls, causing restrictions on their use indoors. Therefore, under existing networks it's difficult to overcome these constraints. The underlying centralized SDN also has a limited capability in offering delay-sensitive services because communication with many nodes creates overload in its processing. Basically, SDN, which means a structure that separates signals from the control plane from packets in the data plane, requires control of the delay-related tree structure available in the event of an emergency during autonomous driving. In these scenarios, the network architecture that handles in-vehicle information is a major variable of delay. Since SDNs in general centralized structures are difficult to meet the desired delay level, studies on the optimal size of SDNs for information processing should be conducted. Thus, SDNs need to be separated on a certain scale and construct a new type of network, which can efficiently respond to dynamically changing traffic and provide high-quality, flexible services. Moreover, the structure of these networks is closely related to ultra-low latency, high confidence, and hyper-connectivity and should be based on a new form of split SDN rather than an existing centralized SDN structure, even in the case of the worst condition. And in these SDN structural networks, where automobiles pass through small 5G cells very quickly, the information change cycle, round trip delay (RTD), and the data processing time of SDN are highly correlated with the delay. Of these, RDT is not a significant factor because it has sufficient speed and less than 1 ms of delay, but the information change cycle and data processing time of SDN are factors that greatly affect the delay. Especially, in an emergency of self-driving environment linked to an ITS(Intelligent Traffic System) that requires low latency and high reliability, information should be transmitted and processed very quickly. That is a case in point where delay plays a very sensitive role. In this paper, we study the SDN architecture in emergencies during autonomous driving and conduct analysis through simulation of the correlation with the cell layer in which the vehicle should request relevant information according to the information flow. For simulation: As the Data Rate of 5G is high enough, we can assume the information for neighbor vehicle support to the car without errors. Furthermore, we assumed 5G small cells within 50 ~ 250 m in cell radius, and the maximum speed of the vehicle was considered as a 30km ~ 200 km/hour in order to examine the network architecture to minimize the delay.

Studies on the Mechanical Properties of Weathered Granitic Soil -On the Elements of Shear Strength and Hardness- (화강암질풍화토(花崗岩質風化土)의 역학적(力學的) 성질(性質)에 관(關)한 연구(硏究) -전단강도(剪斷强度)의 영향요소(影響要素)와 견밀도(堅密度)에 대(對)하여-)

  • Cho, Hi Doo
    • Journal of Korean Society of Forest Science
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    • v.66 no.1
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    • pp.16-36
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    • 1984
  • It is very important in forestry to study the shear strength of weathered granitic soil, because the soil covers 66% of our country, and because the majority of land slides have been occured in the soil. In general, the causes of land slide can be classified both the external and internal factors. The external factors are known as vegetations, geography and climate, but internal factors are known as engineering properties originated from parent rocks and weathering. Soil engineering properties are controlled by the skeleton structure, texture, consistency, cohesion, permeability, water content, mineral components, porosity and density etc. of soils. And the effects of these internal factors on sliding down summarize as resistance, shear strength, against silding of soil mass. Shear strength basically depends upon effective stress, kinds of soils, density (void ratio), water content, the structure and arrangement of soil particles, among the properties. But these elements of shear strength work not all alone, but together. The purpose of this thesis is to clarify the characteristics of shear strength and the related elements, such as water content ($w_o$), void ratio($e_o$), dry density (${\gamma}_d$) and specific gravity ($G_s$), and the interrelationship among related elements in order to decide the dominant element chiefly influencing on shear strength in natural/undisturbed state of weathered granitic soil, in addition to the characteristics of soil hardness of weathered granitic soil and root distribution of Pinus rigida Mill and Pinus rigida ${\times}$ taeda planted in erosion-controlled lands. For the characteristics of shear strength of weathered granitic soil and the related elements of shear strength, three sites were selected from Kwangju district. The outlines of sampling sites in the district were: average specific gravity, 2.63 ~ 2.79; average natural water content, 24.3 ~ 28.3%; average dry density, $1.31{\sim}1.43g/cm^3$, average void ratio, 0.93 ~ 1.001 ; cohesion, $ 0.2{\sim}0.75kg/cm^2$ ; angle of internal friction, $29^{\circ}{\sim}45^{\circ}$ ; soil texture, SL. The shear strength of the soil in different sites was measured by a direct shear apparatus (type B; shear box size, $62.5{\times}20mm$; ${\sigma}$, $1.434kg/cm^2$; speed, 1/100mm/min.). For the related element analyses, water content was moderated through a series of drainage experiments with 4 levels of drainage period, specific gravity was measured by KS F 308, analysis of particle size distribution, by KS F 2302 and soil samples were dried at $110{\pm}5^{\circ}C$ for more than 12 hours in dry oven. Soil hardness represents physical properties, such as particle size distribution, porosity, bulk density and water content of soil, and test of the hardness by soil hardness tester is the simplest approach and totally indicative method to grasp the mechanical properties of soil. It is important to understand the mechanical properties of soil as well as the chemical in order to realize the fundamental phenomena in the growth and the distribution of tree roots. The writer intended to study the correlation between the soil hardness and the distribution of tree roots of Pinus rigida Mill. planted in 1966 and Pinus rigida ${\times}$ taeda in 199 to 1960 in the denuded forest lands with and after several erosion control works. The soil texture of the sites investigated was SL originated from weathered granitic soil. The former is situated at Py$\ddot{o}$ngchangri, Ky$\ddot{o}$m-my$\ddot{o}$n, Kogs$\ddot{o}$ng-gun, Ch$\ddot{o}$llanam-do (3.63 ha; slope, $17^{\circ}{\sim}41^{\circ}$ soil depth, thin or medium; humidity, dry or optimum; height, 5.66/3.73 ~ 7.63 m; D.B.H., 9.7/8.00 ~ 12.00 cm) and the Latter at changun-long Kwangju-shi (3.50 ha; slope, $12^{\circ}{\sim}23^{\circ}$; soil depth, thin; humidity, dry; height, 10.47/7.3 ~ 12.79 m; D.B.H., 16.94/14.3 ~ 19.4 cm).The sampling areas were 24quadrats ($10m{\times}10m$) in the former area and 12 in the latter expanding from summit to foot. Each sampling trees for hardness test and investigation of root distribution were selected by purposive selection and soil profiles of these trees were made at the downward distance of 50 cm from the trees, at each quadrat. Soil layers of the profile were separated by the distance of 10 cm from the surface (layer I, II, ... ...). Soil hardness was measured with Yamanaka soil hardness tester and indicated as indicated soil hardness at the different soil layers. The distribution of tree root number per unit area in different soil depth was investigated, and the relationship between the soil hardness and the number of tree roots was discussed. The results obtained from the experiments are summarized as follows. 1. Analyses of simple relationship between shear strength and elements of shear strength, water content ($w_o$), void ratio ($e_o$), dry density (${\gamma}_d$) and specific gravity ($G_s$). 1) Negative correlation coefficients were recognized between shear strength and water content. and shear strength and void ratio. 2) Positive correlation coefficients were recognized between shear strength and dry density. 3) The correlation coefficients between shear strength and specific gravity were not significant. 2. Analyses of partial and multiple correlation coefficients between shear strength and the related elements: 1) From the analyses of the partial correlation coefficients among water content ($x_1$), void ratio ($x_2$), and dry density ($x_3$), the direct effect of the water content on shear strength was the highest, and effect on shear strength was in order of void ratio and dry density. Similar trend was recognized from the results of multiple correlation coefficient analyses. 2) Multiple linear regression equations derived from two independent variables, water content ($x_1$ and dry density ($x_2$) were found to be ineffective in estimating shear strength ($\hat{Y}$). However, the simple linear regression equations with an independent variable, water content (x) were highly efficient to estimate shear strength ($\hat{Y}$) with relatively high fitness. 3. A relationship between soil hardness and the distribution of root number: 1) The soil hardness increased proportionally to the soil depth. Negative correlation coefficients were recognized between indicated soil hardness and the number of tree roots in both plantations. 2) The majority of tree roots of Pinus rigida Mill and Pinus rigida ${\times}$ taeda planted in erosion-controlled lands distributed at 20 cm deep from the surface. 3) Simple linear regression equations were derived from indicated hardness (x) and the number of tree roots (Y) to estimate root numbers in both plantations.

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Comparison of Two Methods for Estimating the Appearance Probability of Seawater Temperature Difference for the Development of Ocean Thermal Energy (해양온도차에너지 개발을 위한 해수온도차 출현확률 산정 방법 비교)

  • Yoon, Dong-Young;Choi, Hyun-Woo;Lee, Kwang-Soo;Park, Jin-Soon;Kim, Kye-Hyun
    • Journal of the Korean Association of Geographic Information Studies
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    • v.13 no.2
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    • pp.94-106
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    • 2010
  • Understanding of the amount of energy resources and site selection are required prior to develop Ocean Thermal Energy (OTE). It is necessary to calculate the appearance probability of difference of seawater temperature(${\Delta}T$) between sea surface layer and underwater layers. This research mainly aimed to calculate the appearance probability of ${\Delta}T$ using frequency analysis(FA) and harmonic analysis(HA), and compare the advantages and weaknesses of those methods which has used in the South Sea of Korea. Spatial scale for comparison of two methods was divided into local and global scales related to the estimation of energy resources amount and site selection. In global scale, the Probability Differences(PD) of calculated ${\Delta}T$ from using both methods were created as spatial distribution maps, and compared areas of PD. In local scale, both methods were compared with not only the results of PD at the region of highest probability but also bimonthly probabilities in the regions of highest and lowest PD. Basically, the strong relationship(pearson r=0.96, ${\alpha}$=0.05) between probabilities of two methods showed the usefulness of both methods. In global scale, the area of PD more than 10% was less than 5% of the whole area, which means both methods can be applied to estimate the amount of OTE resources. However, in practice, HA method was considered as a more pragmatic method due to its capability of calculating under various ${\Delta}T$ conditions. In local scale, there was no significant difference between the high probability areas by both methods, showing difference under 5%. However, while FA could detect the whole range of probability, HA had a disadvantage of inability of detecting probability less than 10%. Therefore it was analyzed that the HA is more suitable to estimate the amount of energy resources, and FA is more suitable to select the site for OTE development.

Cerebrolysin Attenuates Astrocyte Activation Following Repetitive Mild Traumatic Brain Injury: Implications for Chronic Traumatic Encephalopathy (만성외상성뇌병증과 관련된 반복적 경도 외상성뇌손상(rmTBI)모델에서 cerebrolysin의 별아교 세포활성 억제효과)

  • Kang, Hyun Bae;Kim, GiHun;Kim, HyunJoong;Han, Sa Rang;Chae, Dong Jin;Song, Hee-Jung;Kim, Dong Woon
    • Journal of Life Science
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    • v.23 no.9
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    • pp.1096-1103
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    • 2013
  • Chronic traumatic encephalopathy (CTE), which is common in athletes, is a progressive neurodegenerative disease and a long-term consequence of repetitive closed head injuries. CTE is regarded as a chronic brain syndrome due to the effects of repetitive traumatic brain injury (TBI). Because neurotrophic factors are neuroprotective in models of brain and spinal cord injuries, we examined the effects of cerebrolysin, a mixture of various neurotrophic factors, on brain pathology in a mouse model of repetitive mild TBI (rmTBI), which is a good model of CTE. Five groups were created and treated as follows: groups 1 and 2: rmTBI for 4 weeks following cerebrolysin injection for 4 weeks; groups 3 and 4: rmTBI for 8 weeks with or without cerebrolysin injection for 4 weeks; group 5: control. We found that p-tau expression was increased in the pyramidal layer of the cortex and hippocampus, particularly the CA3 region, but not in the CA1 region and the dentate gyrus (DG). Intra-tail vein administration of cerebrolysin ($10{\mu}l$ of 1 mg/ml) after/during rmTBI treatment reduced p-tau expression in both the cortex and hippocampus. Histological analysis revealed mild astrocyte activation (increased expression of glial fibrillary acidic protein (GFAP)) but not microglia activation (ionized calcium binding adaptor molecule 1 (iba-1) expression) and peripheral macrophage infiltration (CD45). Additionally, administration of cerebrolysin after rmTBI resulted in reduced astrocyte activation. These observations in rmTBI demonstrated that cerebrolysin treatment reduces phosphorylation of tau and astrocyte activation, attenuates brain pathology, and mitigates function deficits in TBI. Taken together, our observations suggest that cerebrolysin has potential therapeutic value in CTE.