• Title/Summary/Keyword: VALLEYS

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Distribution of Anions in Valley Area (계곡지역의 산소음이온 분포)

  • Kim, Ik San;Lee, Duk An;Park, Song In;Ha, Hoon;Yang, Su In
    • Journal of Korean Society of Environmental Engineers
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    • v.36 no.4
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    • pp.246-250
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    • 2014
  • This study was carried out to investigate the anion-distribution of the famous valleys in Jeollanam-do. Sampling sites were the valley region of Eochi, Surak, Daeheungsa and Namchang. The maximum values of the anion level were 11,190~178,100 ea/mL at each site and the highest value was measured at the Surak. The mean values showed 14,060 ea/mL in Surak, 8,590 in Eochi, 8,420 in Daeheungsa and 7,020 in Namchang. For a day, the highest Concentration showed in the 5:00 a.m to 7:00 a.m and the lowest values showed in the 12:00 p.m to 14:00 p.m. According to the distance from the source, the anion tended to disappear within 7 m in Namchang and Daeheungsa. But, it influenced by 50 m in Eochi and Surak. Correlation coefficient was -0.54 with wind speed, 0.34 with humidity about the formation of anion. There was no significant correlation with wind speed in the island and longevity village where we had studied in 2009 and 2011. But there was similar correlation with humidity in the island region. Therefore, we can say that wellbeing life is walking around the valley early in the morning with no wind.

Basic Study on Damaged Area Types and Improvement Idea of the National Park (국립공원의 훼손지 유형과 개선방안에 대한 기초적 연구)

  • Yeom, Sung-Jin
    • Journal of Environmental Science International
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    • v.24 no.11
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    • pp.1405-1415
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    • 2015
  • This study is conducted to determine the damage, distinguish the types and identify the restoration by that type for 13 Korea national parks out of 21. There are 21 Korea national parks are in Korea covering 6.67% of the country or $6,656km^2$ ($3,902km^2$ on land and $2,754km^2$ in the sea) currently since the area around Jirisan ($440km^2$) was designated as the first Korea national parks in 1967. With the cancellation of entrance admission on Korea national parks since 2007, annual visitors to the Korea national parks have grown from 37 millions in 2008 to 46 millions by 2013 and continue to grow due to numerous leisure activities, alpine activities and social changes. As such, Korea national parks are natural resource with high value to be conserved and are attracting significant attention as recreational spaces for people at the same time. On the other hand, there have been issues of soil erosions or disturbed vegetation due to increased number of visitor to the national parks. Korea national parks area damage to its type and damage characteristics to analyse the 13 Korea national parks out of 21 on July 2012 March, Korea national parks over the subjects of the National Park from damaged area status Survey analysis by the Korea National Park Service. As a result, 203 million units in the 16 Korea national parks damaged land of the reform package during ecological trail (including non-regular hiking trails) 153 (77.66%), damaged valleys 20(9.14%) independent damaged area, 13 disconnected ecological axis(7.61%), closed trail(2.03%) (3.55%), and line type damage(like a non-regular hiking trails) appears to be a high ratio. Korea national parks damaged land of the results identified, by contrast ratio and the annual number of visitors Bukhansan national park(49.26%), Gyeongju national park(23.65%) damaged land rates, such as Seorasan national park(4.93%), Songnisan national park (4.43 %), Gyeryongsan national park(3.45%), and the annual number of visitors be similar result. The National Park Service has been reporting on damages and restorations but damages and their types have not been established yet. Damages have been generally studied and categorized on hiking trails due caused by heavy traffic on them but the reports were limited on hiking trails only. Since damage to the Korea national parks are not limited on the hiking trails, it is necessary to determine damages in various aspects. Thus, in this study, damage types, spatial characteristics, causes and restorations are analyzed based on the survey results of damages to national parks in order to provide a basis for the efficient management and operation of the Korea national parks.

Analysis of Distribution and Association Structure on the Sawtooth Oak (Quercus acutissima) Forest in Korea (한국 상수리나무(Quercus acutissima)림의 분포와 군집구조 분석)

  • Kim, In-Taek;Song, Min-Sub;Jung, Sung-Hun
    • Journal of Life Science
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    • v.19 no.3
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    • pp.356-361
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    • 2009
  • This study has targeted Quercus acutissima forests in Korea and has classified the association between Quercus acutissima forests by using the phytosociological method. In addition, the correlation between each association, distribution, potential natural vegetation, and aspect of Quercus acutissima forest according to location have been analyzed to examine the characteristics of the Korean Quercus acutissima forests. Through factor analysis of DECORANA, it was revealed that Quercetum serrato-acutissimae forms in the basal zones of mountains, Quercetum mongolico-acutissimae is formed in the highlands, in the relatively high mountain area, and Carpino-Quercetum acutissimae is mainly distributed in valleys. However, this phenomenon is not very obvious, as each association structure is often mixed up. This result is caused by inhomogeneity of the Quercus acutissima forests, and most of it is distributed in basal zones or around farmlands where there are severe disturbance factors. The proposed potential natural vegetation of the Quercus acutissima forests in Korea is as follows; Quercetum serrato-acutissimae$\rightarrow$Quercus aliena-Quercus serrata community$\rightarrow$Quercus serrata community, Quercetum mongolico-acutissimae$\rightarrow$Quercus aliena-Quercus mongolica community$\rightarrow$Quercus mongolica community, Carpino-Quercetum acutissimae$\rightarrow$Quercus aliena-Carpinus laxiflora community$\rightarrow$Carpinus laxiflora community.

Reclamation of the Closed/Abandoned Coal Mine Overburden Using Lime wastes from Soda Ash Production (부산석회를 활용한 휴ㆍ폐 석탄광산 폐기물의 안정화 및 식생복원)

  • 김휘중;양재의;옥용식;유경열;박병길;이재영;전상호
    • Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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    • 2004.09a
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    • pp.37-47
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    • 2004
  • In Korea, over three hundreds of the coal mines were closed or abandoned due to the depression of the mining industry since the late 1980s. Many of them locate in the steep mountain valleys and the coal mine wastes had been disposed without a proper treatment From these mines, enormous amounts of coal mine overburdens have been abandoned in the slopes and the ample amounts of acid mine drainage (AMD) from either portal or overburdens have been discharging directly to the streams, causing the detrimental effects on soil and water qualities. Objectives of this research were to reclaim the coal mine overburdens using the lime waste cake from the soda ash production by stabilizing the overburden slopes, introducing the vegetation alleviate the environmental problems caused by the closed coal mines. The percentages of the grass distribution ratio (%) and the surface coverage ($\textrm{cm}^2$) in each treatment plot were determined during June to August after seed spraying grasses such as orchard grass (Dactylis glomerata L), Kentucky Bluegrass (Poa pratensis L.) and Eulalia (Miscanthus sinensis Anderss) at the end of May. The grasses covered only 15.5 % of the coal overburden plot at the early stage but the coverage was increased with time to 33% in August. Growth of such grasses was enhanced with the combined treatments of lime waste and topsoil resulting in the increased surface coverage by the grasses. The Increment of the surface coverage from June to August was higher with lime waste treatments. The distribution percentages and surface coverage were highest when the lime wastes were treated at 25 % of the lime requirement. This might be related with the high salt contents in the hire wastes. Results demonstrated that the amounts of lime wastes at 25% of the lime requirement were sufficient for neutralizing the acidic coal overburden and introducing the re-vegetation. Either layering between the coal waste and topsoil or mixing with coal overburdens could be adopted as the lime waste treatment method. The combined treatment of lime wastes and topsoil was recommended for re-vegetation in the coal overburden slopes. The lime wastes from the soda ash production might have a potential to be recycled for the reclamation of the abandoned coal mines to alleviate the environmental problems associated with coal mine waste.

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Dependency of Phonon-limited Electron Mobility on Si Thickness in Strained SGOI (Silicon Germanium on Insulator) n-MOSFET (Strained SGOI n-MOSFET에서의 phonon-limited전자이동도의 Si두께 의존성)

  • Shim Tae-Hun;Park Jea-Gun
    • Journal of the Institute of Electronics Engineers of Korea SD
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    • v.42 no.9 s.339
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    • pp.9-18
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    • 2005
  • To make high-performance, low-power transistors beyond the technology node of 60 nm complementary metal-oxide-semiconductor field-effect transistors(C-MOSFETs) possible, the effect of electron mobility of the thickness of strained Si grown on a relaxed SiGe/SiO2/Si was investigated from the viewpoint of mobility enhancement via two approaches. First the parameters for the inter-valley phonon scattering model were optimized. Second, theoretical calculation of the electronic states of the two-fold and four-fold valleys in the strained Si inversion layer were performed, including such characteristics as the energy band diagrams, electron populations, electron concentrations, phonon scattering rate, and phonon-limited electron mobility. The electron mobility in an silicon germanium on insulator(SGOI) n-MOSFET was observed to be about 1.5 to 1.7 times higher than that of a conventional silicon on insulator(SOI) n-MOSFET over the whole range of Si thickness in the SOI structure. This trend was good consistent with our experimental results. In Particular, it was observed that when the strained Si thickness was decreased below 10 nm, the phonon-limited electron mobility in an SGOI n-MOSFT with a Si channel thickness of less than 6 nm differed significantly from that of the conventional SOI n-MOSFET. It can be attributed this difference that some electrons in the strained SGOI n-MOSFET inversion layer tunnelled into the SiGe layer, whereas carrier confinement occurred in the conventional SOI n-MOSFET. In addition, we confirmed that in the Si thickness range of from 10 nm to 3 nm the Phonon-limited electron mobility in an SGOI n-MOSFET was governed by the inter-valley Phonon scattering rate. This result indicates that a fully depleted C-MOSFET with a channel length of less than 15 m should be fabricated on an strained Si SGOI structure in order to obtain a higher drain current.

An Objective Procedure to Decide the Scale Factors for Applying Land-form Classification Methodology Using TPI (TPI 응용에 의한 산악지형 분류기법의 적용을 위한 scale factor 선정방법 개발)

  • Jang, Kwangmin;Song, Jungeun;Park, Kyeung;Chung, Joosang
    • Journal of Korean Society of Forest Science
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    • v.98 no.6
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    • pp.639-645
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    • 2009
  • The objective of this research was to introduce the TPI approach for interpreting land-forms of mountain forests in South Korea. We develop an objective procedure to decide the scale factor as a basic analytical unit in land-form classification of rugged mountain areas using TPI. In order to determine the scale factor associated with the pattern of slope profiles, the gradient variance curve was derived from a revised hypsometric curve developed using the relief energy of topographic profiles. Using the gradient variance curve, found was the grid size with which the change in relief energy got the peak point. The grid size at the peak point was determined as the scale factor for the study area. In order to investigate the performance of the procedure based on the gradient variance curve, it was applied to determination of the site-specific scale factors of 3 different terrain conditions; highly-rugged, moderately-rugged and relatively less-rugged. The TPI associated with the corresponding scale factors by study site was, then, determined and used in classifying the land-forms. According to the results of this study, the scale factor gets shorter with more rugged terrain conditions. It was also found that the numbers of valleys and ridges estimated with TPI show almost the same trends as those of the observed and the scale factors tends to approach to the mean distance of ridges.

HISTOMORPHOMETRIC STUDY OF DENTAL IMPLANTS WITH RBM AND SLA SURFACE IN THE RABBIT TIBIA (토끼 경골에서 치과용 임프란트의 RBM 및 SLA 표면처리에 따른 조직계측학적 연구)

  • Song, Kook-Hyeon;Kim, Il-Kyu;Jang, Kum-Soo;Kim, Kyu-Nam;Choi, Jin-Ung
    • Journal of the Korean Association of Oral and Maxillofacial Surgeons
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    • v.32 no.6
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    • pp.514-523
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    • 2006
  • The purpose of the present study was to evaluate the effects of several implant surface treatments to the bone formation, by placing Machined implants, 75${\mu}m$ Calcium phosphate-blasted implants and $Al_2O_3$-blasted and acid-etched implants in rabbit tibia through histomorphometric study. Two animals of each group were sacrificed at 2, 4, 8 weeks. The specimens containing the implants were dehydrated and embedded into hard methylmethacrylate plastic. Thereafter, the sections were ground to 50${\mu}m$. The specimens were stained with Villanueva bone stain for a light microscopic study. The results were as follows; 1. When the surface roughness of three different implants was measured by Surfcorder, the Ra of the Machined group, the RBM group and the SLA group was 0.16${\mu}m$, 0.44${\mu}m$, and 1.08${\mu}m$. 2. When examining the surfaces of the implants in the scanning microscope, Machined implant has the smooth surface with a few scratches, RBM implant has the rough surface with curled ridges and valleys, and SLA implant has the rough surface structures such as sharp protruding parts and micropits measuring 1-2${\mu}m$ in diameter. 3. After 2 weeks of implantation, the percentage of bone-to-implant contact of the Machined group, the RBM group and the SLA group was 26.86%, 35.40% and 45.99%. However, its differences between each group decreased during the healing periods. 4. After 2 weeks of implantation, the percentage of bone area inside the threads of the Machined group, the RBM group and the SLA group were 21.55%, 30.43% and 41.18%. However, its difference of bone area between machined group and surface treatment groups was maintained but the difference within the surface treatment groups decreased during the healing periods. In summary, the amount of bone formation in RBM and SLA group was greater than Machined group in early healing stage. These results suggest that RBM and SLA implants can reduce the healing period for osseointegration and may be suitable for early function.

The Development of Valley Scenic Site Zoning Method for the Effective Landscape Protection (계곡 명승의 효과적인 경관보호를 위한 구역 설정기법 개발)

  • Ha, Tae-Il;Kim, Choong-Sik
    • Journal of the Korean Institute of Traditional Landscape Architecture
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    • v.32 no.3
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    • pp.183-190
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    • 2014
  • Since Scenic Sites, heritages to protect the value of landscapes, include valleys and mountains, the cultural heritage protection zones and historical and cultural environments preservation districts are designated extensively. So the landscape protection effects of the designation of scenic sites should be examined. Accordingly, the purpose of this research is to present the methods of efficient institution of district for landscape protection of scenic sites. As the research subject, Cheongamjeong Pavilion and Seokcheongyegok Valley in Bonghwa (Scenic Site No. 60), which has the highest designation rate, was selected. The results of this research using the cumulative visibility technique of GIS are as follows. First, the method of selecting the viewpoint by preparing the reverse cumulative visibility from important landscape resources of the valley was presented. The reverse cumulative visibility can be utilized for rational selection of the viewpoint with regard to scenic sites. Second, the landscape analysis method in consideration of human viewing angle and the visibility of the background of landscape resources was developed. Third, the hierarchical landscape protection method of scenic sites utilizing cumulative visibility was presented. Fourth, it was established through on-site inspections that the method of institution of district is the practical method.

A Study on the Original Planting Form and Management of Vegetation of the Scenic site Nr. 60 Chungam Pavilion and Seokchun Valley in Bonghwa (명승 제60호 봉화 청암정과 석천계곡의 식재 원형 및 식생 관리 방안에 관한 연구)

  • Yee, Sun
    • Journal of the Korean Institute of Traditional Landscape Architecture
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    • v.32 no.4
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    • pp.73-84
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    • 2014
  • This research has conducted historical data analysis and on-site investigation on Chungam Pavilion and Seokchun Valley in Bonghwa. Based on the results, the original planting form was identified, and the vegetation management were drawn up. The results of this study can be summarized as follows. First of all, The Book of Seokchun states that there used to be forest trees such as pine tree, saw-leaf zelkova and maple tree, and flowering trees such as peony, royal azalea, rose, chrysanthemum, and lotus, planted around Chungamjeong. Around Seokchunjeongsa, there used to be boxwood, bamboo, maple, peach, gooseberry and peony planted in the area. Through this discovery it can be realized that the vicinity of Chungam Pavilion and Seokchunjeongsa provided not only the grand aesthetics of four clear seasons, but also planting landscapes with various symbolistic significance and meanings. The description of the planting situation in the historical records offers a useful reference for future vegetation management in Chungam Pavilion, Seokchunjeongsa and surrounding valleys. Furthermore, it holds critical value in the identification of planting pattern in late Chosun dynasty. Second, the planting landscape in and around Chungam Pavilion and Seokchunjeongsa will have to be maintained as described in the historical records The Book of Seokchun. Also, the once famous colony of pine trees in the area is gradually reducing in its scale, which calls for active management measures such as elimination of broadleaf trees.

Case study of landslide types in Korea (우리나라 산사태의 형태분류에 따른 사례)

  • 김원영;김경수;채병곤;조용찬
    • The Journal of Engineering Geology
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    • v.10 no.2
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    • pp.18-35
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    • 2000
  • The most dominant type of landslide in Korea is debris flows which mostly take place along mountain slopes during the rainy season, July to August. The landslides have been reported to begin activation when rainfall is more than 200mm within 2days. The debris flows are usually followed by translational slips which occur upper part of mountain slopes and they transit to debris flow as getting down to the valleys. Lithology, location, slope inclination, grain size distribution of soil, permeability, dry density and porosity have been proved as triggering factor causing translational slides. The triggering data taken from mapping are statistically analysed to get landslide potential quantitatively. Rock mass creeps mostly occur on well bedded sedimentary rocks in Kyeongsang Basin. Although the displacement of rock mass creep is relatively small about 1m, the creep can cause severe hazards due to relatively large volume of the involved rock mass. Examples are rock mass creep occurred in the mouth of Hwangryongsan Tunnel, in Chilgok and in Sachon in 1999. Although the direct factor of the creeps are due to slope cutting at the foot area, more attention is required A rotational slide occurring within thick soil formation or weathered rock is also closely related to bottom part of slope cutting. It is propagated circular or semi-circular type. Especially in korea, the rotational slide may be frequently occurred in Tertiary tuff area. Because they are mainly composed of volcanic ash and pyroclastic materials, well developed joints and high degree of swelling and absorption can easily cause the slide. The landslide among the Pohang-Guryongpo national road is belong to this type of slide.

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