• Spatial Information Research
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• v.6 no.1
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• pp.91-102
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• 1998

The objectives of this research were to develop fish-habitat relationship models which can be used to estimate fish species riclmess of small and medium rivers in Korea, and test the accuracy of the models. The models are based on the Aquatic GAP Analysis model in the New York Cooperative Fish & Wildlife Research Unit (19%), and they employ three habitat factors; river size, physical habitat, and water quality of each river segment. Model 1 and model II are based on the water quality standard for life support of EP A and the water quality class of Korea, respectively. Test sites for this study include one urban stream and three less spoiled tributaries of the Han River. The results of this research can be summarized as follows. First, the number of habitat types identified by model I and model II are nine and 14, respectively. Second, the average accuracy of the three distribution maps of rare or endangered fish species are 80.6% (model 1) and 81.2% (model II). Third, the accuracy of fish species richness are 94% (model 1) and 95% (model II), and the water quality is the most important factor affecting fish species richness. Fourth, the accuracy of fish species list are 50.5% (model 1) and 68.7% (model II), but the accuracy of less spoiled stream segments and that of polluted stream segments are 67.1% and 86.5%, respectively. Finally, it can be concluded that the overall performance of model II is better than that of model I at our test sites.

• Journal of Korea Water Resources Association
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• v.48 no.10
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• pp.831-843
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• 2015

This study estimates MODIS-derived evapotranspiration data quality by revised RS-PM algorithm in Seolmacheon test basin. We used latent flux with eddy covariance method to evaluate MODIS-derived spatial evapotranspiration and gap-filled these data by three methods (FAO-PM, MDV and Kalman Filter) and to quantify daily evapotranspiration. Gap-filled daily evapotranspiration data was used to evaluate evapotranspiration computed by revised RS-PM algorithm derived MODIS satellite images. For the water budget analysis, we used soil moisture content that is quantified to average individual soil moisture rate observed by TDR (Time Domain Reflectometry) sensor at soil depth. The soil moisture variation is calculated in consideration from initial to final soil moisture content. According to the result of this study, evapotranspiration computed by revised RS-PM algorithm is very larger than eddy covariance data gap-filled by three methods. Also, water budget characteristics is not closed. We could analysis that MODIS-derived spatial evapotranspiration does not represent actual evapotranspiration in Seolmacheon.

• Korean Journal of Remote Sensing
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• v.37 no.5_1
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• pp.885-901
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• 2021

This paper illustratesthe impact of the temporal gap between satellite images and targetsize in mesoscale atmospheric motion vector (AMV) algorithm. A test has been performed using GEO-KOMPSAT-2A (GK2A) rapid-scan data sets with a temporal gap varying between 2 and 10 minutes and a targetsize between 8×8 and 40×40. Resultsshow the variation of the number of AMVs produced, mean AMV speed, and validation scores as a function of temporal gap and target size. As a results, it was confirmed that the change in the number of vectors and the normalized root-mean squared vector difference (NRMSVD) became more pronounced when smaller targets are used. In addition, it was advantageous to use shorter temporal gap and smaller target size for the AMV calculation in the lower layer, where the average speed is low and the spatio-temporal scale of atmospheric phenomena is small. The temporal gap and the targetsize are closely related to the spatial and temporalscale of the atmospheric circulation to be observed with AMVs. Thus, selecting the target size and temporal gap for an optimum calculation of AMVsrequires considering them. This paper recommendsthat the optimized configuration to be used operationally for the near-real time analysis of mesoscale meteorological phenomena is 4-min temporal gap and 16×16 pixel target size, respectively.

• Proceedings of the Korean Society of Medical Physics Conference
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• 2002.09a
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• pp.411-414
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• 2002

The CdTe semiconductor detector has a higher detection efficiency for x-rays and $\square$amma rays and a wider energy band gap compared with Si and Ge semiconductor detectors. Therefore, the size of the detector element can be made small, and can be operated at room temperature. The interaction between a CdTe detector and incident x-rays is mainly photoelectric absorption in the photon energy range of up to 100 keV. In this energy range, Compton effects are almost negligible. We have developed a 256 channel CdTe array detector system for monochromatic x-ray CT using synchrotron radiation. The CdTe array detector system, the element size of which is 1.98 mm (h) x 1.98 mm (w) x 0.5 mm (t), was operated in photon counting mode. In order to improve the spatial resolution, we tilted the CdTe array detector against the incident parallel monochromatic x-ray beam. The experiments were performed at the BL20B2 experimental hutch in SPring-8. The energy of incident monochromatic x-rays was set at 55 keV. Phantom measurements were performed at the detector angle of 0, 30 and 45 degrees against the incident parallel monochromatic x-rays. The linear attenuation coefficients were calculated from the reconstructed CT images. By increasing the detector angle, the spatial resolutions were improved. There was no significant difference between the linear attenuation coefficients which were corrected by the detector angle. It was found that this method was useful for improving the spatial resolution in a parallel monochromatic x-ray CT system.

• Journal of the Economic Geographical Society of Korea
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• v.26 no.3
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• pp.310-323
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• 2023

Urbanization and income distribution issues are global interest, and the results of studies on the impact of urbanization on income inequality are different for each country and period. This study analyzes the impact of urbanization on income inequality using regional data from 2000-2021. In particular, serial correlation, spatial dependence, and common factor effects of the Gini coefficient are confirmed and analyzed through a dynamic spatial panel regression model. As a result, urbanization has a positive effect on reducing income inequality. Therefore, it is necessary to continuously promote regional urbanization to improve the income distribution problem. Areas with already high urbanization rates should reduce income inequality by narrowing the wage gap by expanding training opportunities for low-skilled workers, and need to come up with measures to prevent counter-urbanization.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.9 no.5
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• pp.1096-1101
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• 2005

An efficient method of estimating the spatial gaps between the connected components has been prposed to separatethe individual words from a handwritten legal amount on bank check. Owing to the inherent problem of underestimation or overestimation, the previous gap measures have much difficulty in being applied to the legal amounts that usually include the great shape variability by writer's unconstrained writing style and touching or irregular gaps between words by space limitation. In order to alleviate such burden and improve word separation performance, we have developed a modified version of each distance measure. Through a series of word separation experiments, we found that the modified distance measures show a better performance with over $2-3\%$ of the word separation rate than their corresponding original distance measures.

• Journal of Intelligence and Information Systems
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• v.19 no.4
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• pp.81-96
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• 2013

Video information retrieval has become a very important issue because of the explosive increase in video data from Web content development. Meanwhile, content-based video analysis using visual features has been the main source for video information retrieval and browsing. Content in video can be represented with content-based analysis techniques, which can extract various features from audio-visual data such as frames, shots, colors, texture, or shape. Moreover, similarity between videos can be measured through content-based analysis. However, a movie that is one of typical types of video data is organized by story as well as audio-visual data. This causes a semantic gap between significant information recognized by people and information resulting from content-based analysis, when content-based video analysis using only audio-visual data of low level is applied to information retrieval of movie. The reason for this semantic gap is that the story line for a movie is high level information, with relationships in the content that changes as the movie progresses. Information retrieval related to the story line of a movie cannot be executed by only content-based analysis techniques. A formal model is needed, which can determine relationships among movie contents, or track meaning changes, in order to accurately retrieve the story information. Recently, story-based video analysis techniques have emerged using a social network concept for story information retrieval. These approaches represent a story by using the relationships between characters in a movie, but these approaches have problems. First, they do not express dynamic changes in relationships between characters according to story development. Second, they miss profound information, such as emotions indicating the identities and psychological states of the characters. Emotion is essential to understanding a character's motivation, conflict, and resolution. Third, they do not take account of events and background that contribute to the story. As a result, this paper reviews the importance and weaknesses of previous video analysis methods ranging from content-based approaches to story analysis based on social network. Also, we suggest necessary elements, such as character, background, and events, based on narrative structures introduced in the literature. We extract characters' emotional words from the script of the movie Pretty Woman by using the hierarchical attribute of WordNet, which is an extensive English thesaurus. WordNet offers relationships between words (e.g., synonyms, hypernyms, hyponyms, antonyms). We present a method to visualize the emotional pattern of a character over time. Second, a character's inner nature must be predetermined in order to model a character arc that can depict the character's growth and development. To this end, we analyze the amount of the character's dialogue in the script and track the character's inner nature using social network concepts, such as in-degree (incoming links) and out-degree (outgoing links). Additionally, we propose a method that can track a character's inner nature by tracing indices such as degree, in-degree, and out-degree of the character network in a movie through its progression. Finally, the spatial background where characters meet and where events take place is an important element in the story. We take advantage of the movie script to extracting significant spatial background and suggest a scene map describing spatial arrangements and distances in the movie. Important places where main characters first meet or where they stay during long periods of time can be extracted through this scene map. In view of the aforementioned three elements (character, event, background), we extract a variety of information related to the story and evaluate the performance of the proposed method. We can track story information extracted over time and detect a change in the character's emotion or inner nature, spatial movement, and conflicts and resolutions in the story.

• Journal of the Korean Geographical Society
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• v.43 no.4
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• pp.511-525
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• 2008

Residential segregation is often considered to be one of the social problems that intensify urban inequality This study reviews three different frameworks about the causes of residential segregation and tests their validity in the real world. The review focuses on racial/ethnic residential segregation in U.S. cities since it has been blamed for persistent socio-economic gap among racial/ethnic groups. The three different segregation frameworks include 'spatial assimilation' that attributes segregation to low degree of assimilation and acculturation, 'place stratification' to discriminatory practices in the housing and mortgage markets such as steering, blockbusting, and redlining, and 'resurgent ethnicity' to racial/ethnic preference in residential choice, particularly in-group attraction. As an effort to test their validity, the paper examined residential pattern changes of the four major Asian nationality groups through 1990s and found that their residences got decentralized but re-cluster in some selected suburbs. This supports 'resurgent ethnicity' largely and 'spatial assimilation' only partly.

• Korean Journal of Plant Taxonomy
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• v.51 no.3
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• pp.181-191
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• 2021

Tulips are bulbous geophytes that have considerable commercial value worldwide. This genus primarily originated in the Tien Shan and Pamir-Alai mountain ranges, which surround the Ferghana Valley. The Ferghana Valley is home to five sections of the genus Tulipa L, represented by 23 taxa (22 species). However, there is a lack of detailed information about the distribution of Tulipa species in the natural geographic area of the Ferghana Valley. Therefore, to address this knowledge gap, we comprehensively investigated the spatial distribution of all Tulipa species in the valley. To assess the spatial distribution, the entire area was divided into 32 squares consisting of four latitudinal and eight longitudinal zones. The results showed that latitudinal zones B and C with 15 and 13 taxa, respectively, along with five longitudinal zones (A5, B3, B4, C2, and C3) with 5 to 10 taxa were hotspots for this genus. Additionally, the spatial distributions of the species in terms of the corresponding state borders, mountain ranges, endemism, and conservation issues were assessed. The findings of this study provide comprehensive information about the distribution of Tulipa species to assist with conservation initiatives ultimately to ensure the survival of various species.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.24 no.2
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• pp.57-69
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• 2021

Urban green spaces supply ecosystem services (ESs), which are consumed by city residents and generate demand, to improve air quality. It is important to determine supply and demand for ESs and reduce the gap for efficient management. This study proposed a method to use the concept of supply and demand for ESs in the decision-making process for urban planning or management. PM₁₀ concentrations were converted to weight for demand assessment on PM₁₀ reduction, and PM₁₀ absorption capacity of all green spaces including the forests, and that of urban green spaces excluding forests, was calculated for each supply assessment. The differences in the calculated supply and demand were analyzed to derive the mismatched regions in Suwon. As a result, regions with big forested areas showed sufficient supply, indicating that the degree of mismatch among administrative neighborhoods (dong) varied greatly depending on whether they had a forest. An analysis of only urban green spaces showed that all neighborhoods lacked supply. Forests with high PM₁₀ absorption capacity had a great effect, but urban green spaces can be considered a key element in reducing PM₁₀ in daily life. Considering the mismatch of supply and demand, spatial distribution, and population distribution, it is possible to prioritize the supply of urban green spaces to reduce PM₁₀ and, furthermore, support decision making for priority zones subject to forest conservation and designation and cancellation of green spaces, which gives significance to this study.