• Title/Summary/Keyword: Long Valley

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The Structure of the Plant Community in Seonamsagol(Valley), Jogyesan(Mt.) Provincial Park, Suncheon City (순천시 조계산도립공원 선암사골 계곡부 식물군집구조)

  • Kim, Jong-Yup
    • Korean Journal of Environment and Ecology
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    • v.26 no.4
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    • pp.593-603
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    • 2012
  • This study was carried out to investigate the ecological succession sere and conservative value, and to provide the basic data for the planning of the Provincial Park Management in Seonamsagol(Valley), Jogyesan(Mt.) Provincial Park(altitude 884m), Suncheon City, Korea by analysing the structure of the plant community. Twenty plots(size is $20m{\times}20m$) were set up at an altitude of range from 315m to 480m. As a result of analysis of TWINSPAN which is one of the ordination technique, the plant communities were divided into four groups which are community I(Quercus variabilis community), community II(Q. serrata community), community III(Decideous broad-leaved plant community), and community IV(Carpinus tschonoskii community). The warmth index is $104^{\circ}C{\cdot}month$ based on the data of monthly mean temperature during the past thirty years(1981~2010), so we found out that the vegetation of the study site located in the South Temperate Climate Zone. We supposed that the ecological succession sere of the study site is in the early stage of developing from Q. serrata community to Carpinus tshonoskii community, however we should do a long-term monitoring to investigate the changes of the ecological succession each plant community, meanwhile Sasa borealis was dominant species in the shrub layer. The diameter at breast height of specimen tree is range from 20 to 55cm(average 36cm) and the height of that is range from 14 to 35m(average 23cm). The age of community I was 64 years old, that of community II was from 59 to 64 years old, that of community III was from 51 to 62 years old, and that of community IV was from 41 to 68 years old, thus the age of the study site is about from 38 to 72 years old. According to the index of Shnnon's diversity(unit: $400m^2$), community IV was ranged from 0.8452 to 1.2312, community III was ranged from 0.8044 to 1.1404, community II was ranged from 0.8221 to 0.9971, and community I was 0.8324.

Tie Spatial Structure of Ch'ang-ts'ai-ts'un Village A Case Study on a Rural Village of Korean Immigrants in Yen-pien Area of China (중국(中國) 연변지구(延邊地區) 조선족(朝鮮族)마을의 구성(構成) 룡정시 지신향 장재촌을 대상으로)

  • Lee, Kyu Sung
    • Journal of architectural history
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    • v.3 no.1
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    • pp.83-99
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    • 1994
  • Ch'ang-Ts'al-Ts'un is a rural Village near Lung-jing City in Yen-pien Korean Autonomous Province of China. It was formed about 100 years ago by Korean Immigrants and has been developed maintaing the characteristics of traditional Korean architecture. Therefore investigating the spatial structure of this village is a meanigful work to confirm and explore one branch of Korean architecture. This study aims at analyzing the spatial structure of the village using direct data collected from the field work and indirect data from books and maps. The field work consists of on-the-site survey of the village layout, interviews of residents, observation notes and photography. Ch'ang-Ts'ai-Ts'un is located 360-370 m high above the sea level and at the side of a long valley. A river flows in the middle of the valley and relatively flat arable land exists at the both sides of the river. The location of the village related to the surrounding river and mountains suggests that the site of the village was chosen according to Feng-Shui, Chinese and Korean traditional architectural theory. The main direction of the house layouts is South-western. The village has been growing gradually until today. Therefore it is meaningful to make the village layout before Liberation(1946 A.D.) because the characteristics of Korean architecture prevailed more in that period. The area of the previous village is limited to the west side of the creek. New houses were later added to the east of the creek, forming a 'New Village'. Previously the village was composed of 3 small villages: Up, Middle and Down. Also the main access roads connecting the village with the neighboring villages were penetrating the village transversely. Presently the main access road comes to the village longitudinally from the main highway located in front of the village. The retrospective layout shows the existence of well-formed Territory, Places and Axes, thus suggesting a coherent Micro-cosmos. The boundary of imaginery territory perceived by present residents could be defined by linking conspicous outside places sorrounding the village such as Five-mountains, Front-mountain, Shin-dong village, Standing-rock, Rear-mountain and Myong-dong village. Inside the territory there are also the important places such as Bus-stop, Memorial tower of patriots, Road-maitenance building and the village itself. And inside it 5 transverse and 1 longitudinal axes exist in the form of river, roads and mountains. The perceived spatial structure of the village formed by Places, Axes and Territory is geometrical and well-balanced and suggests this village is fit for human settlement. The administrative area of the village is about 738 ha, 27 % of which is cultivated land and the rest is mountain area. Initially the village and surrounndings were covered with natural forest But the trees have been gradually cut down for building and warning houses, resulting in the present barren and artificial landscape with bare mountains and cultivated land. At present the area of the village occupied by houses is wedge-shaped, 600 m wide and 220 m deep in its maximum. The total area of the village is $122,175m^{2}$. The area and the rate of each sub-division arc as follow. 116 house-lots $91,465m^{2}$ (74.9 %) Land for public buildings and shops $2,980m^{2}$ (2.4 %) Roads $17,106m^{2}$ (14.0 %) Creek $1,356m^{2}$ (1.1 %) Vacant spaces and others $9,268m^{2}$ (7.6 %) TOTAL $122,175m^{2}$ (100.0 %) Each lot is fenced around with vertical wooden pannels 1.5-1.8 m high and each house is located to the backside of the lot. The open space of a lot is sub-divided into three areas using the same wooden fence: Front yard, Back yard and Access area. Front and back yards are generally used for crop-cultivation, the custom of which is rare in Korea. The number of lots is 116 and the average size of area is $694.7m^{2}$. Outdoor spaces in the village such as roads, vacant spaces, front yard of the cultural hall, front yard of shops and spacse around the creek are good 'behavioral settings' frequently used by residents for play, chatting, drinking and movie-watching. The road system of the village is net-shaped, having T-junctions in intersections. The road could be graded to 4 categories according to their functions: Access roads, Inner trunk roads, Connecting roads and Culs-de-sac. The total length of the road inside the village is 3,709 m and the average width is 4.6 m. The main direction of the road in the village is NNE-SSE and ESE-WNW, crossing with right angles. Conclusively, the spatial structure of Ch'ang-Ts'ai-Ts'un village consists of various components in different dimensions and these components form a coherent structure in each dimension. Therefore the village has a proper spatial structure meaningful and appropriate for human living.

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A Study on the Garden Culture and Ideology based on the Confucianism and Taoism of the Song Dynasty - Focused on Zhū Xī(朱熹) and Báiyùchán(白玉蟾) - (송대(宋代) 유가와 도교에 근거한 원림 문화와 사상 고찰 - 주희(朱熹)와 백옥섬(白玉蟾)을 중심으로 -)

  • Park So-Hyun
    • Journal of the Korean Institute of Traditional Landscape Architecture
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    • v.41 no.1
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    • pp.10-20
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    • 2023
  • Zhū Xī, the representative of Confucianism, and Báiyùchán, the representative of Taoism in the South Song Dynasty, showed different sense of appreciation and enjoyment on the same space that was Mountain Wǔyí in their ideologically cultural ways. Based on the temples Wŭyíjīngshè(武夷精舍) where Zhū Xī stayed and Zhĭzhĭān(止止庵) where Báiyùchán resided, this study revealed their lives in such temples to look into their appreciation on ideology and space. Then, based on the words 'YiBoEumYeong [移步吟詠]' shown on the poetry they chanted in relation with Wǔyíjiǔqū from its 1st valley to its 9th valley, this study examines their understanding of scenery and system of appreciation that appeared in dynamic ways to conclude: First, even same scenery shows different understanding of scenery and appreciation of space in accordance with the viewers' thinking ways of culture. Second, as the Confucianism and Taoism influenced in ideologically cultural ways to develop each other in the Song dynasty, they absorbed their merits each other to supplement shortcomings in their own. In this process, they made it clear that their own propositions were different between them in their essential meanings although they used common terms for such propositions. Third, as the Confucian master who compiled the Neo-Confucianism of the South Song dynasty, Zhū Xī regarded Wŭyíjīngshè and Wǔyíjiǔqū as a place of learning and a place of seeking the truth to go for 'being unified with nature' so that everyday life can be united with Tao of Li [理] everywhere beyond the limited appreciation of the scenery. That is, this thought works for 'recovery of nature of our own [復其性]', the learning goal of Confucianism, and is aimed to 'cultivate the essential nature of our own(性情涵養)' through such beautiful nature. Fourth, as the master of Keumdan family of the South Song Taoism, Báiyùchán regarded Zhĭzhĭān and Wǔyíjiǔqū as a Taoist temple that has a long history rooting from Taesangwon temple, a clean place of discipline to become a Taoist hermit through hard training. He, therefore, directly referred to Zhĭzhĭān and Wǔyíjiǔqū in relation with the Taoist legends remaining in Wǔyíjiǔqū such as hermits' dinners, female hermits, leaving the human world as a hermit and so on as ways for becoming a hermit so that he went for the level of perfectly going out of human world and becoming a hermit. He, therefore, defined Mountain Wǔyí as a world and universe of hermits where he himself too hovered between outside and inside of poetry literature as a hermit through the mood and attitude of keeping himself enjoying the scenery as a hermit.

The Existence and Design Intention of Jeong Seon's True-View Landscape Painting <Cheongdamdo(淸潭圖)> (겸재 정선(謙齋 鄭敾) <청담도(淸潭圖)>의 실재(實在)와 작의(作意))

  • SONG Sukho;JO Jangbin ;SIM Wookyung
    • Korean Journal of Heritage: History & Science
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    • v.56 no.2
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    • pp.172-203
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    • 2023
  • <Cheongdamdo>(true-view landscape painting) was identified in this study to be a folding screen painting painted by Jeong Seon(a.k.a. Gyeomjae, 1676~1759) in the 32nd year of King Yeongjo(1756) while exploring the Cheongdam area located in Mt. Bukhansan near Seoul. Cheongdam Byeol-eop(Korean villa), consisting of Waunru Pavilion and Nongwolru Pavilion, was a cultural and artistic base at that time, where Nakron(Confucian political party) education took place and the Baegak Poetry Society met. <Cheongdamdo> is a painting that recalls a period of autumn rainfall in 1756 when Jeong Seon arrived in the Cheongdam valley with his disciple Kim Hee-sung(a.k.a. Bulyeomjae, 1723~1769) and met Hong Sang-han(1701~1769). It focuses on the valley flowing from Insubong peak to the village entrance. The title has a dual meaning, emphasizing "Cheongdam", a landscape feature that originated from the name of the area, while also referring to the whole scenery of the Cheongdam area. The technique of drastically brushing down(刷擦) wet pimajoon(hanging linen), the expression of soft horizontal points(米點), and the use of fine brush strokes reveal Jeong Seon's mature age. In particular, considering the contrast between the rock peak and the earthy mountain and symmetry of the numbers, the attempt to harmonize yin and yang sees it regarded as a unique Jingyeong painting(眞境術) that Jeong Seon, who was proficient in 『The Book of Changes』, presented at the final stage of his excursion. 「Cheongdamdongbugi」(Personal Anthology) of Eo Yu-bong(1673~1744) was referenced when Jeong Seon sought to understand and express the true scenery of Cheongdam and the physical properties of the main landscape features in the villa garden. The characteristics of this garden, which Jeong Seon clearly differentiated from the field, suppressed the view of water with transformed and exaggerated rocks(水口막이), elaborately creating a rain forest to cover the villa(裨補林), and adding new elements to help other landscape objects function. In addition, two trees were tilted to effectively close the garden like a gate, and an artificial mountain belt(造山帶), the boundary between the outer garden and the inner garden, was built solidly like a long fence connecting an interior azure dragon(內靑龍) and interior white tiger(內白虎). This is the Bibo-Yeomseung painting(裨補厭勝術) that Jeong Seon used to turn the poor location of the Cheongdam Byeol-eop into an auspicious site(明堂). It is interpreted as being devised to be a pungsu(feng shui) trick, and considered an iconographic embodiment of ideal traditional landscape architecture that was difficult to achieve in reality but which was possible through painting.

Characteristic on the Layout and Semantic Interpretation of Chungryu-Gugok, Dongaksan Mountain, Gokseong (곡성 동악산 청류구곡(淸流九曲)의 형태 및 의미론적 특성)

  • Rho, Jae-Hyun;Shin, Sang-Sup;Huh, Joon;Lee, Jung-Han;Han, Sang-Yub
    • Journal of the Korean Institute of Traditional Landscape Architecture
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    • v.32 no.4
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    • pp.24-36
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    • 2014
  • The result of the research conducted for the purpose of investigating the semantic value and the layout of the Cheongryu Gugok of Dorimsa Valley, which exhibits a high level of completeness and scenic preservation value among the three gugoks distributed in the area around Mt. Dongak of Gogseong is as follows.4) The area around Cheongryu Gugok shows a case where the gugok culture, which has been enjoyed as a model of the Neo-Confucianism culture and bedrock scenery, such as waterfall, riverside, pond, and flatland, following the beautiful valley, has been actually substituted, and is an outstanding scenery site as stated in a local map of Gokseong-hyeon in 1872 as "Samnam Jeil Amban Gyeryu Cheongryu-dong(三南第一巖盤溪流 淸流洞: Cheongryu-dong, the best rock mooring in the Samnam area)." Cheongryu Gugok, which is differentiated through the seasonal scenery and epigrams established on both land route and waterway, was probably established by the lead of Sun-tae Jeong(丁舜泰, ?~1916) and Byeong-sun Cho(曺秉順, 1876~1921) before 1916 during the Japanese colonization period. However, based on the fact that a number of Janggugiso of ancient sages, such as political activists, Buddhist leaders, and Neo-Confucian scholars, have been established, it is presumed to have been utilized as a hermit site and scenery site visited by masters from long ago. Cheongryu Gugok, which is formed on the rock floor of the bed rock of Dorimsa Valley, is formed in a total length of 1.2km and average gok(曲) length of 149m on a mountain type stream, which appears to be shorter compared to other gugoks in Korea. The rock writings of the three gugoks in Mt. Dongak, such as Cheongryu Gugok, which was the only one verified in the Jeonnam area, total 165 in number, which is determined to be the assembly place for the highest number of rock writings in the nation. In particular, a result of analyzing the rock writings in Cheongryu Gugok totaling 112 places showed 49pieces(43.8%) with the meaning of 'moral training' in epigram, 21pieces (18.8%) of human life, 16pieces(14.2%) of seasonal scenery, and 12pieces(10.6%) of Janggugiso such as Jangguchur, and the ratio occupied by poem verses appeared to be six cases(3.6%). Sweyeonmun(鎖烟門), which was the first gok of land route, and Jesiinganbyeolyucheon(除是人間別有天) which was the ninth gok of the waterway, corresponds to the Hongdanyeonse(虹斷烟鎖) of the first gok and Jesiinganbyeolyucheon of the ninth gok established in Jaecheon, Chungbuk by Se-hwa Park(朴世和, 1834~1910), which is inferred to be the name of Gugok having the same origin. In addition, the Daeeunbyeong(大隱屛) of the sixth gok. of land route corresponds to the Chu Hsi's Wuyi-Gugok of the seventh gok, which is acknowledged as the basis for Gugok Wollim, and the rock writings and stonework of 'Amseojae(巖棲齋)' and 'Pogyeongjae(抱經齋)' between the seventh gok and eighth gok is a trace comparable with Wuyi Jeongsa(武夷精舍) placed below Wuyi Gugok Eunbyeon-bong, which is understood to be the activity base of Cheongryu-dong of the Giho Sarim(畿湖士林). The rock writings in the Mt. Dongak area, including famous sayings by masters such as Sunsaeuhje(鮮史御帝, Emperor Gojong), Bogahyowoo(保家孝友, Emperor Gojong), Manchunmungywol(萬川明月, King Joengjo), Biryeobudong(非禮不動, Chongzhen Emperor of the Ming Dynasty)', Samusa(思無邪, Euijong of the Ming Dynasty), Baksechungpwoong(百世淸風, Chu Hsi), and Chungryususuk-Dongakpungkyung(淸流水石 動樂風景, Heungseon Daewongun) can be said to be a repository of semantic symbolic cultural scenery, instead of only expressing Confucian aesthetics. In addition, Cheongryu Gugok is noticeable with its feature as a cluster of cultural scenery of the three religions of Confucian-Buddhism-Taoism, where the Confucianism value system, Buddhist concept, and Taoist concept co-exists for mind training and cultivation. Cheongryu Gugok has a semantic feature and spatial character as a basis for history and cultural struggle for the Anti-Japan spirit that has been conceived during the process of establishing and utilizing the spirit of the learning, loyalty for the Emperor and expulsion of barbarians, and inspiration of Anti-Japan force, by inheriting the sense of Dotong(道統) of Neo-Confucianism by the Confucian scholar class at the end of the Joseon era that is represented by Ik-hyun Choi(崔益鉉, 1833~1906), Woo Jeon(田愚, 1841~1922), Woo-man Gi(奇宇萬, 1846~1916), Byung-sun Song(宋秉璿, 1836~1905), and Hyeon Hwang(黃玹, 1855~1910).

Development of a Stock Trading System Using M & W Wave Patterns and Genetic Algorithms (M&W 파동 패턴과 유전자 알고리즘을 이용한 주식 매매 시스템 개발)

  • Yang, Hoonseok;Kim, Sunwoong;Choi, Heung Sik
    • Journal of Intelligence and Information Systems
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    • v.25 no.1
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    • pp.63-83
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    • 2019
  • Investors prefer to look for trading points based on the graph shown in the chart rather than complex analysis, such as corporate intrinsic value analysis and technical auxiliary index analysis. However, the pattern analysis technique is difficult and computerized less than the needs of users. In recent years, there have been many cases of studying stock price patterns using various machine learning techniques including neural networks in the field of artificial intelligence(AI). In particular, the development of IT technology has made it easier to analyze a huge number of chart data to find patterns that can predict stock prices. Although short-term forecasting power of prices has increased in terms of performance so far, long-term forecasting power is limited and is used in short-term trading rather than long-term investment. Other studies have focused on mechanically and accurately identifying patterns that were not recognized by past technology, but it can be vulnerable in practical areas because it is a separate matter whether the patterns found are suitable for trading. When they find a meaningful pattern, they find a point that matches the pattern. They then measure their performance after n days, assuming that they have bought at that point in time. Since this approach is to calculate virtual revenues, there can be many disparities with reality. The existing research method tries to find a pattern with stock price prediction power, but this study proposes to define the patterns first and to trade when the pattern with high success probability appears. The M & W wave pattern published by Merrill(1980) is simple because we can distinguish it by five turning points. Despite the report that some patterns have price predictability, there were no performance reports used in the actual market. The simplicity of a pattern consisting of five turning points has the advantage of reducing the cost of increasing pattern recognition accuracy. In this study, 16 patterns of up conversion and 16 patterns of down conversion are reclassified into ten groups so that they can be easily implemented by the system. Only one pattern with high success rate per group is selected for trading. Patterns that had a high probability of success in the past are likely to succeed in the future. So we trade when such a pattern occurs. It is a real situation because it is measured assuming that both the buy and sell have been executed. We tested three ways to calculate the turning point. The first method, the minimum change rate zig-zag method, removes price movements below a certain percentage and calculates the vertex. In the second method, high-low line zig-zag, the high price that meets the n-day high price line is calculated at the peak price, and the low price that meets the n-day low price line is calculated at the valley price. In the third method, the swing wave method, the high price in the center higher than n high prices on the left and right is calculated as the peak price. If the central low price is lower than the n low price on the left and right, it is calculated as valley price. The swing wave method was superior to the other methods in the test results. It is interpreted that the transaction after checking the completion of the pattern is more effective than the transaction in the unfinished state of the pattern. Genetic algorithms(GA) were the most suitable solution, although it was virtually impossible to find patterns with high success rates because the number of cases was too large in this simulation. We also performed the simulation using the Walk-forward Analysis(WFA) method, which tests the test section and the application section separately. So we were able to respond appropriately to market changes. In this study, we optimize the stock portfolio because there is a risk of over-optimized if we implement the variable optimality for each individual stock. Therefore, we selected the number of constituent stocks as 20 to increase the effect of diversified investment while avoiding optimization. We tested the KOSPI market by dividing it into six categories. In the results, the portfolio of small cap stock was the most successful and the high vol stock portfolio was the second best. This shows that patterns need to have some price volatility in order for patterns to be shaped, but volatility is not the best.

Characteristics of Geomorphological Surface and Analysis of Deposits in Fluvial Terraces at Upper Reach of Soyang River (소양강 상류 하안단구의 지형면 특성과 퇴적물 분석)

  • 이광률
    • 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.

An Analysis of Cold Air Generation Area Considering Climate-Ecological Function -A Case Study of Changwon, South Korea- (기후생태적 기능을 고려한 찬공기 생성지역 분석 -창원시를 대상으로-)

  • Song, Bong-Geun;Park, Kyung-Hun
    • Journal of the Korean Association of Geographic Information Studies
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    • v.13 no.1
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    • pp.114-127
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    • 2010
  • The purpose of this study is to find out cold and fresh air producing areas using climate-ecological functions in Changwon city, Gyeongsangnam-do, South Korea. The evaluation of climate-ecological functions were composed of the six factors: patch size with cold air generation and inflow functions, farmland and grassland ratio, mean slope degree, cross section types, mean slope length and roughness of bottom in valley. The analysis results of each evaluation factor in the study area were divided into 5 grades according to the capacity of cold air generation. The first-grade area with the highest factor values for cold air generation was take up 3.51% of the total study area, second grade was 13.48%, third grade was 31.65%, fourth grade was 27.28%, and fifth grade was 24.09%. According to the spatial distribution of cold air producing areas, the valleys around Mt. Bongnim, Changwon tunnel, and Anmin tunnel had higher evaluation grade. It will require the future research to establish the climate-ecological conservation areas and to construct the wind corridor based on the long-term microclimatic monitoring.

Geochemical Characteristics of the Quaternary Jungok Basalt in Choogaryong Rift Valley, Mid-Korean Peninsula (추가령 열곡대에 분포하는 전곡현무암의 지화학적 특성)

  • Wee, Soo-Meen
    • Economic and Environmental Geology
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    • v.29 no.2
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    • pp.171-182
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    • 1996
  • Quaternary Jungok basalts are distributed along the old Hantan river in Mid-Korean Peninsula. They were flowed out from Mt. Ori and Upland (680 m), and they formed narrow and long basalt plateau showing the layers of 10 to 20 meters in thickness and about 95 km in length. Fifty seven samples were collected from the study area, and sixteen rock samples were selected and analysed for major and trace elements. The analyzed samples have alkalic composition and show a relatively restricted variation in major element chemistry (except MgO), as comparing to the that of trace element. Based on major element chemistry, a quantitative modelling of fractional crystallization by multiple linear regression method suggests that the chemical evolution of the evolved rocks can be generated by fractionation of olivine, plagioc1ase, clinopyroxene, and magnetite in proportion of 56 : 25 : 17 : 2, respectively. The calculated trace element abundances by mineral proportions estimated from major element modelling, however, underestimate the incompatible element concentrations in the evolved rocks. According to the incompatible element abundances, simple fractional crystallization process has difficulty to explain the chemical variation of the evolved rocks. It seems that the other processes, which enrichment of incompatible elements can occure without concomitant changes in major element compositions, are needed in order to explain the chemical variation of the Jungok basalts. Thus, the major elements and compatible trace elements variations of the Jungok basalts are due to fractional crystallization, but the incompatible elements variation is due to fractional crystallization superimposed on already varying concentrations caused by slightly different degrees of melting of the same source, and/or due to periodic replenishment, tapping and fractionation(RTF) processes.

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Long-term Investigation of Soil Chemical Properties in Paddy Fields Located in Different Topographic Areas of Jeonbuk Province

  • Ahn, Byung-Koo;Ko, Do-Young;Lee, Chang-Kyu;Kim, Jin-Ho;Song, Young-Ju;Lee, Jin-Ho
    • Korean Journal of Soil Science and Fertilizer
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    • v.49 no.3
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    • pp.275-281
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    • 2016
  • The aim of this study was to examine the selected soil chemical properties of paddy fields in different topographic areas to efficiently manage nutrient valances of the paddy fields in Jeonbuk Province. Three-hundred soil sampling sites in paddy fields were selected from the different topographic areas in Jeonbuk Province. The soil samples were collected every four years from 1999 to 2015. Soil pH and exchangeable K and Mg concentrations declined during the experimental periods. However, almost all the chemical properties were within the proper levels for paddy soil, except exchangeable Mg concentration. Distributed areas of the paddy fields with soil pH below 5.5 continuously increased, but the paddy fields with lower concentrations of soil organic matter and available $P_2O_5$ than the proper levels declined after 2007. In addition, the paddy fields with available $SiO_2$ below the proper concentration decreased from 83.3% of the total paddy fields studied in 1999 to 61.0% of the total fields investigated in 2015. The paddy fields with lower exchangeable K and Mg than the proper levels increased after 2003 whereas the fields with lower exchangeable Ca concentration decreased. Dominant landform of coastal and plain areas was fluvio-marine plains that was distributed in 53.7% and 40.9%, respectively. Local valley and fans was a dominant landform of mountainous and middle-mountainous areas, which was 51.8% and 67.6%, respectively. Dominant soil textures distributed in coastal and plain areas were silty loam and loam. Those in mountainous and middle-mountainous areas were sandy loam and loam, respectively. Soil pH was relatively higher in coastal area and the comparatively higher content of soil organic matter was found in costal area than other areas. The concentrations of available $P_2O_5$, exchangeable Ca, and exchangeable Mg were generally higher in mountainous, coastal, plain areas, respectively, but available $SiO_2$ and exchangeable K concentrations were not significantly different among the different topographic areas.