• Title/Summary/Keyword: time-geography

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The Geomorphic Changes of Sand-Beach Coasts by Human Impact in Byeonsan Peninsula, Southwest Korea (인간간섭에 따른 변산반도 사빈해안의 지형변화)

  • CHOI, Hoon;LEE, Min-Boo
    • Journal of The Geomorphological Association of Korea
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    • v.19 no.3
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    • pp.83-96
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    • 2012
  • The origins of beaches at Byeonsan Peninsular, as a pocket type, are classified to a sand barrier type and wave-cut type. The beaches had developed by the deposition of the silt and clay layers on the 10m height from sea level in the inner bay during climax era of postglacial transgression. At that time, some sands had blown toward the inland hills to form aeolian deposits. After postglacial sea-level stabilization, sometimes, there has been the negative budget of beach materials. Recently, beaches have been transformed by human impact such as construction of Saemangeum sea-wall, especially in the Byeonsan and Gosapo beaches being close to the sea-wall. So the speed of tidal currents become slower and comparatively depositoinal activity stronger. And the level of chemical weathering has been higher. In Byeonsan beach, the ratio of coarse sand decreased with higher ratio of finer materials and by beach erosion dissected runnels developed, running parallel to the coastline. In Gosapo beach, supply of suspended materials are increased through the Garyeok drainage gate, the sands tend to be finer.

A study on the change of chemical composition of sediment particles of terrace deposits - A case of fine sediments at Jeongdongjin area - (단구 퇴적층의 화학 조성 변화에 대한 연구 - 정동진 단구의 세립 물질을 사례로 -)

  • Kim, Jong Yeon
    • Journal of The Geomorphological Association of Korea
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    • v.23 no.2
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    • pp.29-45
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    • 2016
  • Chemical composition of fine sediments from Jeongdongjin area are analyzed with XRF method. The results are compared with previously reported results of sandstones of the nearest Simgok port. The weight percentage of $SiO_2$ of the samples are far lower than those of sandstones of Simgok. It is supposed to be happened by the selective elution of $SiO_2$ from the sediment layer of coastal terrace, as there's no evidence of selective input or precipitation of other elements from outside. As a result of chemical alteration or weathering of sediment at coastal terrace, weight percentage of $Al_2O_3$ and $Fe_2O_3$ of samples show far higher values than those of Simgok sandstone. In addition, the relative portion of $Al_2O_3$ and $Fe_2O_3$ are decreased to upward within outcrop of terrace sediment layers. It could be caused by the chemical weathering progress with time. However Chemical Index of alteration(CIA) of sediment samples are no larger than 90 and it could be interpreted that it would take over 100ka for total weathering of sediment in this area. Meanwhile the ratio of $SiO_2/Al2O_3$ of terrace sediment showed as 3.48~6.0 and it is far smaller than those of Simgok sandstones(23.9~49.0). The ratio of $SiO_2/Fe_2O_3$ of terrace sediment(19.19~55.85) showed similar pattern with $SiO_2/Al2O_3$ (Simgok sanstone: 119.6~601.8). The ratios have a weak trend of decreasing upwards within the outcrop, there also a huge difference in value among the samples. Chemical composition of reddish brown and gray layers which suspected as the result of psudogleization reveals that reddish brown parts have higher concentration of $Fe_2O_3$ than other parts, while there was no significant difference in concentration of $Al_2O_3$ and CaO.

The Validity of Delimitation of City Center by Land Values and the Change in the Land Values of City Center (지가에 의한 도심 경계 설정의 타당성 및 도심의 지가 변화)

  • Park, Jieun
    • Journal of the Economic Geographical Society of Korea
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    • v.22 no.3
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    • pp.366-379
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    • 2019
  • The purpose of this study is to review how to set city center's boundaries in proportion to the highest land values and to identify the characteristics and influence of the original and the new city center. For this purpose, the land values was compared and analyzed the city of Busan as an example using officially announced land price in 2000 and 2015. The main findings of the study are as follows. First, the method of delimitation city center's boundaries as a percentage of the highest land values depends on the flow of time or the social and economic situation of each city, so a careful approach should be taken. Second, the original city center's land values have a strong influence on the surrounding areas. However, given that the PLVI was moved to the new city center and new city center's land prices has increased, it is predicted that the new city center's area in Busan will grow further in the future.

A Study on the Regional Specialization of Protected Horticulture in Seongju-gun, Gyeongsangbuk-do, the Center of the Main Oriental Melon Production Area (시설원예농업의 지역적 전문화 연구: 경상북도 성주군 참외 주산지를 중심으로)

  • Jang, Youngjin
    • Journal of the Economic Geographical Society of Korea
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    • v.24 no.3
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    • pp.217-231
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    • 2021
  • This study was conducted to identify the regional specialization that occurred during industrialization of agriculture. It examined patterns in oriental melons as one of the produce leading the development of the domestic protected horticulture sector. Oriental melons have been cultivated indoors for a long time. Seongju-gun, Gyeongsangbuk-do is specializing in oriental melon cultivation through increasingly intensive production and spatial concentration and is now the largest oriental melon production area in South Korea. This paper first discusses the production intensification and spatial concentration of oriental melon cultivation at the national level and then examines the specialization of oriental melon cultivation in Seongju-gun in terms of land use, cultivation facilities and related technologies, and the division of labor. This examination was based on relevant statistics and in-depth interviews with main actors from the area.

Sulzbacheromyces sinensis, an Unexpected Basidiolichen, was Newly Discovered from Korean Peninsula and Philippines, with a Phylogenetic Reconstruction of Genus Sulzbacheromyces

  • Liu, Dong;Wang, Xin Yu;Wang, Li Song;Maekawa, Nitaro;Hur, Jae-Seoun
    • Mycobiology
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    • v.47 no.2
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    • pp.191-199
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    • 2019
  • Most of lichens are formed by Ascomycota, less than 1% are lichenized Basidiomycota. The flora investigation of lichenized Ascomycota of South Korea has been well studied in the past three decades; however, prior to this study, none of basidiolichens was discovered. During the recent excursion, an unexpected clavarioid basidiolichen, Sulzbacheromyces sinensis was collected. Morphology and ecology has been recorded in detail. DNA was extracted, and ITS, 18S, 28S nuclear rDNA were generated. In order to further confirm the systematic position of the Korean specimens, maximum likelihood and Bayesian inference analysis including all the species of the order Lepidostromatales were conducted based on the ITS. As a result, the phylogenetic tree of the order Lepidostromatales was reconstructed, which differed from the previous studies. The inferred phylogenetic tree showed that species of Sulzbacheromyces in three different continents (Asia, South Africa and South America) were separated into three clades with support. In this study, the species worldwide distribution map of Lepidostromatales was illustrated, and S. sinensis had a widest distribution range (paleotropical extend to the Sino-Japanese) than other species (paleotropical or neotropical). Prior to this study, the range of distribution, southernmost and northernmost points and the fruiting time of S. sinensis were recorded, and the genus Sulzbacheromyces was firstly reported from Korean peninsula and Philippines.

Trend analysis of rainfall characteristics and its impact on stormwater runoff quality from urban and agricultural catchment

  • Salim, Imran;Paule-Mercado, Ma. Cristina;Sajjad, Raja Umer;Memon, Sheeraz Ahmed;Lee, Bum-Yeon;Sukhbaatar, Chinzorig;Lee, Chang-Hee
    • Membrane and Water Treatment
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    • v.10 no.1
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    • pp.45-55
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    • 2019
  • Climate change has significantly affected the rainfall characteristics which can influence the pollutant build-up and wash-off patterns from the catchment. Therefore, this study explored the influence of varying rainfall characteristics on urban and agricultural runoff pollutant export using statistical approaches. For this purpose, Mann-Kendall and Pettitt's test were applied to detect the trend and breakpoint in rainfall characteristics time series. In addition, double mass curve and correlation analysis were used to drive the relationship between rainfall-runoff and pollutant exports from both catchments. The results indicate a significant decreased in total rainfall and average rainfall intensity, while a significant increased trend for antecedents dry days and total storm duration over the study periods. The breakpoint was determined to be 2013 which shows remarkable trend shifts for total rainfall, average rainfall intensity and antecedents dry days except total duration. Double mass curve exhibited a straight line with significant rainfall-runoff relationship indicates a climate change effect on both sites. Overall, higher pollutant exports were observed at both sites during the baseline period as compared to change periods. In agricultural site, most of the pollutants exhibited significant (p< 0.05) association with total rainfall, average rainfall intensity and total storm duration. In contrast, pollutants from urban site significantly correlated with antecedent dry days and average rainfall intensity. Thus, total rainfall, average rainfall intensity and total duration were the significant factors for the agricultural catchment while, antecedents dry days and average rainfall intensity were key factors in build-up and wash-off from the urban catchment.

The Characteristics of Migration in Gangwon Innovation City and Wonju Company Town (강원혁신도시와 원주기업도시의 인구이동 특성 분석)

  • Hong, Giljong;Bae, Sunhak
    • Journal of the Economic Geographical Society of Korea
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    • v.24 no.3
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    • pp.300-312
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    • 2021
  • The purpose of this study was to compare and analyze characteristics of Gangwon Innovation City and Wonju Company Town. Both were created with similar purpose, place, time, and scale. However, they were created with different approaches: relocating public institutions and attracting private institutions. For research data, population microdata provided by the National Statistical Office were used. As a result of the analysis, the Gangwon Innovation City and the Wonju Company Town greatly influenced the population growth of Wonju and the movement of the population within Wonju. The influx of population into the study area brought positive changes in both demographic structure and population indices. Excluding relocation to Wonju-si, Innovation Cities and Company Town accounted for more than 50% of those who migrated from the metropolitan area (Seoul, Gyeonggi and Incheon). The supply of apartment houses (apartments) in the Innovation City and the Company Town stimulated the transfer from the inside of Wonju to this area. For households that moved to Gangwon Innovation City and Wonju Company Town, the most common reasons for moving in were housing, occupation, and family.

The Examination of the Limitations of Using the OSL Dates Derived from this Study in the Correlation of MIS 5 Marine Terraces Distributed in the Southeastern Coast of the Korean Peninsula (한반도 남동부 해안 해성단구의 분류와 편년에 있어서 본 연구에서 도출된 OSL 연대 적용의 한계성 검토)

  • Choi, Seong Gil;Tamura, Toshikazu;Miyauchi, Takahiro;Tsukamoto, Sumiko
    • Journal of The Geomorphological Association of Korea
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    • v.25 no.4
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    • pp.63-75
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    • 2018
  • The lower marine terrace 1 and 2 surfaces distributed between Ulsan and Pohang coast in the southeastern coast of the Korean penninsula have been correlated with MIS 5e and 5a (or 5c) by amino acid dates, 14C dates, wide-spread tephra correlation and pollen analysis respectively. In this study, to test the reliability of the OSL method for the estimation of the numerical burial age of marine sediment deposits, we analyzed the samples from the marine terraces which have been known as typical marine terraces formed during MIS 5e and MIS 5a in the above-mentioned coast. The burial ages of the marine deposit of the lower marine terrace 1 and 2, with paleoshoreline altitudes of 18m to 19m and 10m to 11m respectively, both showed about the same age of 60 ka BP. The lower marine terraces 1 and 2, however, were divided into two terrace surfaces by a clear terrace cliff. Besides, the OSL dates of the lower and upper parts of the lower marine terrace 2 of the Bonggil coast showed the reversed burial ages. In the lower marine terrace 1 of the Sanhari coast, almost the same burial ages were derived from both the lower part (marine rounded gravel layer) and the upper part (terrestrial angular gravel layer) of the terrace deposit. Therefore, at the present time, judging from only the OSL dates measured in this study, it could be argued that the OSL method is not the best for the estimation of forming periods of the lower marine terraces 1 and 2 and their classification.

The Squat Represented in The Good Terrorist: Lessing's Politics of Place (『순진한 테러리스트』에 재현된 스?하우스-레싱의 장소정치학)

  • Park, Sun Hwa
    • English & American cultural studies
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    • v.14 no.1
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    • pp.27-51
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    • 2014
  • Doris Lessing describes a band of revolutionaries who become involved in terrorist activities far beyond their level of competence in The Good Terrorist. Alice Mellings who is from a middle-class family has organized a squat house in London and seems capable of controlling everyone around her and anything about the house. She is seemingly like a housekeeper or a breadwinner. She also likes to be on the battlefront, for instance, demonstrating, picketing and spray-painting slogans. Such is able to easily exploit the others and she increasingly becomes the leader in the house. Recently some critics have focused on the political and social roles of the protagonist who represents a voice of terrorists in the 1980s England. Based on this, The Good Terrorist is read with the concept of the subject of feminism that Gillian Rose adopts in order to show that this subject tries to avoid the exclusion of the master subject. This subject imagines spaces which are not structured through masculinist claims to exhaustiveness. Alice as the subject of feminism shows different roles; she extorts or steals money for the maintenance of the house from her affluent parents; she spends all her time cleaning, fixing, decorating the deserted house; and she looks after the official affairs related to the house with her skills and experiences. She is systematically in charge of the house and sits at the head of the table in the kitchen. But when their activities turn into disaster and their plans fail, Alice willingly decides to close down the house after ousting the members. Here in her extorted gaze it is revealed that she takes control over the working class members of the house who are unable to lead a revolution because of their own problems and thereby the working class are dominated by the middle class. That is, the place is paradoxically recreated based on class differences, which the revolutionaries try to break. By representing the deconstruction and recreation of the place through squat houses, Lessing reveals her implicit feminism in which a new place should be produced crossing the principle of the dichotomy of gender and class.

An analysis of the change in media's reports and attitudes about face masks during the COVID-19 pandemic in South Korea: a study using Big Data latent dirichlet allocation (LDA) topic modelling (빅데이터 LDA 토픽 모델링을 활용한 국내 코로나19 대유행 기간 마스크 관련 언론 보도 및 태도 변화 분석)

  • Suh, Ye-Ryoung;Koh, Keumseok Peter;Lee, Jaewoo
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.25 no.5
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    • pp.731-740
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    • 2021
  • This study applied LDA topic modeling analysis to collect and analyze news media big data related to face masks in the three waves of the COVID-19 pandemic in Korea. The results empirically show that media reports focused on mask production and distribution policies in the first wave and the mandatory mask wearing in the second wave. In contrast, more reports on trivial, gossipy events consist of the media coverage in the second and third waves. The findings imply that Korea's governmental interventions to address the shortage of face masks and to regulate mask wearing were successful relatively in a short time. In contrast, the study also reports that there may be relative less number of science-based news reports like the ones on the effectiveness of face masks or different levels of filter types. This study exemplifies how a big data analysis can be applied to evaluate and enhance public health communication.