• Title/Summary/Keyword: areal characteristics

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Establishing the Managerial Boundary of the Baekdu-daegan: An Approach by Watershed Expanding Process (백두대간 관리범위 설정에 관한 연구: 유역확장방식에 의한 접근)

  • Kwon, Taeho;Choi, Song-Hyun;Yoo, Ki-Joon
    • Journal of the Korean Association of Geographic Information Studies
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    • v.5 no.4
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    • pp.106-118
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    • 2002
  • In recent years, synthetic and systematic management with conservation-oriented strategy for Baekdu-daegan, which is the greatest chine as well as the major ecological axis of the Korean Peninsula, is being required to cope adequately with the various kinds of developmental urge. For this, spatially definite zoning for the managerial area on Baekdu-daegan has to be completed first. This study is to take into consideration the traditional concepts of stream and watershed as well as the actual disturbance on Daegan area, and to propose the process for reasonably establishing the managerial boundary adjacent to the Ridges. The case site with topographically diverse characteristics was selected, and the analyses on watershed, road network and land use were carried out using the digital maps and Landsat TM images. Based on these analyses results, the managerial boundaries as alternatives from the Ridges were produced by watershed expansion process, and used for tracing the changes of road occupancy rate and the areal ratio of various land use types to the relevant watersheds to search out the adequate managerial boundary. The results show that watershed expansion process could be effective tool for establishing the managerial boundary, and the fourth expanded watershed would be included for the adequate managerial boundary of the case site.

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The Characteristics of Intra-Urban Migration in Seoul (서울시 내부 인구이동의 특성에 관한 연구)

  • Choi, Eun-Young;Cho, Dae-Heon
    • Journal of the Korean association of regional geographers
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    • v.11 no.2
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    • pp.169-186
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    • 2005
  • This paper has focused on the geographical patterns of migrations and the influence of housing value(apartment) per pyung on the migrations within the one city(Seoul) for 1995$\sim$2003. The migration flows which are composed of the origin, the destination and the number of migrants, are examined at the administrative gu and dong level. As most migrations occur among adjacent gus and dongs, short-distance migration is prominent But there is a tendency for the short-distance migrations to occur between specific regions. Since the economic crisis of 1997 out of which Korea was rescued by IMF, differentiation of housing price is so evident that residental relocation is selective among dongs. It seems that the differentiation of housing price has begun to facilitate the relocation of households. Certain social groups are excluded from high-quality residences, as they cannot afford the high price. The number of migrants between dongs is closely related to the variation of the housing value per pyung within dongs. The short-distance migration may reflect this phenomena simultaneously. It seems that the intra-urban migrations in Seoul play a important role to produce and reinforce the residential segregation.

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Surface Sediments of the Continental Shelf and Slope off the Southeastern Coast of Korea (한국 동남해역 대륙붕과 대륙사면 표면퇴적물의 분포와 특성)

  • Lee, Chang-Bok;Park, Yong Ahn;Choi, Jin-Yong;Kim, Gi-Beom
    • 한국해양학회지
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    • v.24 no.1
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    • pp.39-51
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    • 1989
  • A total of 139 surface sediment samples, collected from the continental shelf and slope off the southeastern coast of Korea, were analyzed in order to understand their grain-size, mineral composition and organic carbon content. Based on the grain-size characteristics, five surface sedimentary facies were distinguished: sand, clay, mud, sand-mud mixed, and sand-clay mixed facies. The sand facies appears to be composed mostly of relict sand. For mud, most of which seem to be of recent origin, two different sources were suggested, based principally on their areal distribution pattern and the local hydrographic conditions. Heavy mineral composition of the fine-sand size fraction allowed us to distinguish different sand populations from the study area. On the whole, the Hupo Bank sediments showed a high content of garnet, while the sediments from the northern part of the continental shelf were characterized by a relatively high content of metamorphic minerals (kyanite, sillimanite, andalusite, staurolite). Among clay minerals, the most abundant was illite, with chlorite, kaolinite and smectite following in decreasing order. Organic carbon contents in the sediments of the study area were generally high and showed an average value of 1.94%. The sediment grain-size exerted a strong influence on the organic carbon content. The highest organic carbon content, on the other hand, was found in the continental slope sediments.

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Geochemistry of the Chuncheon amphibolite and its origin: (1) major elements (춘천 각섬암의 지구화학과 기원:(1) 주성분원소)

  • 권성택;조문섭;전은영;이승렬;이진한
    • The Journal of the Petrological Society of Korea
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    • v.4 no.1
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    • pp.20-30
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    • 1995
  • We report major element chemistry of the Chuncheon amphibolite in the Precambrian Kyonggi massif and discuss its origin. On the basis of areal distribution and chemical difference, the Chuncheon amphibolite can be divided into the Gubongsan arnphibolite in the Gubongsan Group east of Chuncheon city and the Sangguli amphibolite in the Yongduri gneiss complex occurring to the southeast of the Gubongsan Group. Overall major element characteristics of the Chuncheon amphibolite indicate an igneous precursor, although it shows concordant relationship with metasedimentary rocks in many cases. The parental rock of the amphibolite has tholeiitic composition with 45-53wt% $SiO_2$. The Sangguli amphibolite has lower MgO than the Gubongsan one. The difference in $TiO_2$/P_2O_5 ratio between the two amphibolites suggests that they are not genetically related. In MgO variation diagrams, $Na_2O$, $Fe_2O_3$ and $Al_2O_3$ show scattered pattern, while MgO has positive correlation with CaO and negative one with $SiO_2$, $TiO_2$, $P-2O_5$ and $K_2O$. These variations can be interpreted as the result of differentiation of basaltic magma with fractionation of olivine, pyroxene, and plagioclase. Tectonic discrimination using major elements generally suggest withinplate environment for the Chuncheon amphibolite which is similar to that of the amphibolite in the Ogcheon belt.

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An ESDA Tool for Time-series Spatial Association (지역분석을 위한 시계열 공간연관성 탐색도구)

  • Ahn Jae-Seong;Park Key-Ho;Lee Yang-Won
    • Spatial Information Research
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    • v.14 no.1 s.36
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    • pp.163-176
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    • 2006
  • The concept of 'spatial association' explains spatial distribution pattern of geographical phenomenon based on similarity with neighborhoods, as in the Tobler's Law of Geography: 'Everything is related to everything else, but near things are more related than distant things.' In this study, we develop a time-series exploratory analysis tool for discovering temporal patterns of spatial association by combining spatial statistics and geo-visualization, and thus present a possibility to support spatial decision-making process. As for the spatial proximity weight matrix indispensable to measuring global and local spatial association, we employ a variety of flexible weighting schemes using geometric characteristics of areal unit. In addition, we renovate the existing visualization methods for more effective understanding of the procedures and results of time-series analysis on spatial association: for instance, temporal parallel coordinate plot with box plot, animated map for spatial association, and 3D Moran scatterplot. The feasibility of our system is verified by time-series analysis experiments on the spatial association of land price fluctuation rate for all administrative units in Korea, $1995{\sim}2004$.

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Evaluation of the Impact of Land Surface Condition Changes on Soil Moisture Field Evolution (지표면 조건의 변화에 따른 토양수분의 변화 평가)

  • Yu, Cheol-Sang
    • Journal of Korea Water Resources Association
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    • v.31 no.6
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    • pp.795-806
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    • 1998
  • Soil moisture is affected by regional climate, soil characteristics and land surface condition, etc,. Especially, the changes in land surface condition is more than other factors, which is mainly due to rapid urbanization and industrialization. This study is to evaluate how the change of land surface condition impacts on soil moisture field evolution using a simple model of soil moisture dynamics. For the quantification of soil moisture field, the first half of the paper is spared for the statistical characterization based on the first- and second-order statistics of Washita '92 and Monsoon '90 data. The second half is for evaluating the impact of land cover changes through simulation study using a model for soil moisture dynamics. The model parameters, the loss rate and the diffusion coefficient, have been estimated using the observed data statistics, where the changes of surface conditions are considered into the model by applying various parameter sets with different second-order statistics. This study is concentrated on evaluating the impact due to the changes of land surface condition variability. It is because we could easily quantify the impact of the changes of its areal mean based on the linear reservoir concept. As a result of the study, we found; (1)as the variability of land surface condition, increases, the soil moisture field dries up more easily, (2)as the variabilit y of the soil moisture field is the highest at the beginning of rainfall and decreases as time goes on to show the variability of land surface condition, (3)the diffusion effect due to surface runoff or water flow through the top soil layer is limited to a period of surface runoff and its overall impact is small compared to that of the loss rate field.

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Geochemical Characteristics of the Continental Shelf and Slope Sediments off the Southeastern Coast of Korea (한국 동남해역 대륙붕과 대륙사면 표층퇴적물의 지화학적 특성)

  • Lee, Chang-Bok;Park, Yong-Ahn;Kang, Hyo-Jin;Kim, Dae-Chul
    • The Korean Journal of Quaternary Research
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    • v.5 no.1
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    • pp.15-31
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    • 1991
  • A total of 90 surface sediment samples, collected from the continental margin area bordering east and southeast coast of Korea, were subject to the geochemical analyses with the aim of filling the gap in our knowledge of this environment. The analyzed items included the major elements (Al, Fe, Mg, Ca, K, Na, p and Mn), organic carbon, and some trace metals (Ba, Co, Cu, Sr and Zn). The sediment grain-size exerted a predominant influence on the contents of most elements, with the exceptions of Ca, K, Sr and Ba. The Ca and Sr contents, being closely interrelated each other, were mainly controlled by the calcium carbonate content. The K content, on the other hand, appeared to be influenced by both illite and feldspar. The Ba content showed a certain relationship with that of K, suggesting a common source of these two elements; potassium feldspar. The R-mode factor analysis result also reaffirmed the above-mentioned controlling factors on the sediment geochemistry. The grain-size dependency of trace metals obscures their areal distribution pattern from the total contents. However, with the metal/aluminum ratios we could differentiate the subtle difference in the metal enrichment. Hence, sediments of the southern coastal area appear to receive some anthropogenic inputs of metals, though the effect is still negligible.

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The Changing Process of the Tidal Landforms in Hampyeung Bay, Southwest Korea (함평만의 간석지 해안지형의 변화)

  • KIM, Nam-Shin;LEE, Min-Boo
    • Journal of The Geomorphological Association of Korea
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    • v.18 no.4
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    • pp.223-233
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    • 2011
  • The aims of this study is about distribution characteristics of tidal coastal landforms, and that changing process in the Hampyeung Bay, which has a semi-enclosed bay like basin shape without inflow of stream, the mouth of open sea is narrow and forms with wide ends toward inland sea. The source of deposits are moved materials by tidal currents and from coastal slopes. Main landform elements of study area consist of tidal flat, tidal channels, intertidal sand bar, sea cliffs, and sea terrace. Tidal flats is classified with mud flat and mixed flat by grain size composition. Mud flats have developed at the shoreline area that tidal flat is closed to the continuity of gentle slope, and mixed flat developed at the foot of the sea cliffs and sea terraces. Quaternary deposits were identified in the coastal materials sedimented by the sea-level change. According to the analysis of grain size composition during last ten years, sands and silt has increased 2% and 6% respectively, clay has been decreased by 9%. The concaved tidal flats are colonized by salt plants. Areal changes of salt plants expanded near four times from 2.4km2 at the year 2001 to 9.3km2 at the year 2009. During the same periods, mean grain size became coarser from 6.5φ to 4.5φ at the salt plants area.

Commuting Efficiency Comparison of Metropolitan Areas in South Korea: Application of Constrained Monte-Carlo Simulation to Avoid the MAUP (우리나라 대도시권 통근 효율성 비교: MAUP 회피를 위한 Constrained Monte-Carlo Simulation의 활용)

  • Hyunseong Yun;Seung-Nam Kim
    • Land and Housing Review
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    • v.15 no.2
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    • pp.73-87
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    • 2024
  • To evaluate the efficiency of commuting patterns, various commuting indicators such as excess commute and commuting potential utilized have been developed and used. It is crucial to calculate these indicators reasonably to reveal the differences in commuting patterns among metropolitan areas and to consider these in the process of formulating commuting policies. However, commuting indicators are generally calculated at the administrative district level, and thus, they are not free from the problem of the modifiable areal unit problem (MAUP). This issue can undermine the rationality of comparing commuting efficiency between metropolitan areas, making it necessary to handle the calculation of commuting indicators carefully. Therefore, this study utilises Monte Carlo Simulation to calculate optimal, actual, and maximum commuting distances, and thereby presents the excess commute and the commuting potential utilized. To apply Monte Carlo Simulation to the context of South Korea, a constrained Monte Carlo Simulation is conducted, where residential and workplace locations used in the simulation are selected based on the actual locations of buildings. The analysis is conducted on 13 metropolitan areas with established metropolitan plans using the 2016 Household Travel Survey data. The commuting indicators calculated through the simulation showed minimal differences compared to the results obtained through conventional methods. The comparison of commuting efficiency among metropolitan areas revealed that even if the degree of spafial balance between residential and workplace locations is similar, the actual commuting patterns can differ significantly. It is suggested that further research considering characteristics such as the area of each metropolitan region will be necessary in the future.

Characteristics of Vertical Ozone Distributions in the Pohang Area, Korea (포항지역 오존의 수직분포 특성)

  • Kim, Ji-Young;Youn, Yong-Hoon;Song, Ki-Bum;Kim, Ki-Hyun
    • Journal of the Korean earth science society
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    • v.21 no.3
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    • pp.287-301
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    • 2000
  • In order to investigate the factors and processes affecting the vertical distributions of ozone, we analyzed the ozone profile data measured using ozonesonde from 1995 to 1997 at Pohang city, Korea. In the course of our study, we analyzed temporal and spatial distribution characteristics of ozone at four different heights: surface (100m), troposphere (10km), lower stratosphere (20km), and middle stratosphere (30km). Despite its proximity to a local, but major, industrial complex known as Pohang Iron and Steel Co. (POSCO), the concentrations of surface ozone in the study area were comparable to those typically observed from rural and/or unpolluted area. In addition, the findings of relative enhancement of ozone at this height, especially between spring and summer may be accounted for by the prevalence of photochemical reactions during that period of year. The temporal distribution patterns for both 10 and 20km heights were quite compatible despite large differences in their altitudes with such consistency as spring maxima and summer minima. Explanations for these phenomena may be sought by the mixed effects of various processes including: ozone transport across two heights, photochemical reaction, the formation of inversion layer, and so on. However, the temporal distribution pattern for the middle stratosphere (30km) was rather comparable to that of the surface. We also evaluated total ozone concentration of the study area using Brewer spectrophotometer. The total ozone concentration data were compared with those derived by combining the data representing stratospheric layers via Umkehr method. The results of correlation analysis showed that total ozone is negatively correlated with cloud cover but not with such parameter as UV-B. Based on our study, we conclude that areal characteristics of Pohang which represents a typical coastal area may be quite important in explaining the distribution patterns of ozone not only from surface but also from upper atmosphere.

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