• Korean Journal of Remote Sensing
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• v.35 no.3
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• pp.415-431
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• 2019

The satellite-viewed cloudiness, a ratio of cloudy pixels to total pixels ($C_{sat,\;prev}$), inevitably differs from the "ground-viewed" cloudiness ($C_{grd}$) due to different viewpoints. Here we develop an algorithm to retrieve the satellite-viewed, but adjusted cloudiness to $C_{grd} (C_{sat,\;adj})$. The key process of the algorithm is to convert the cloudiness projected on the plane surface into the cloudiness on the celestial hemisphere from the observer. For this conversion, the supplementary satellite retrievals such as cloud detection and cloud top pressure are used as they provide locations of cloudy pixels and cloud base height information, respectively. The algorithm is tested for Himawari-8 level 1B data. The $C_{sat,\;adj}$ and $C_{sat,\;prev}$ are retrieved and validated with $C_{grd}$ of SYNOP station over Korea (22 stations) and China (724 stations) during only daytime for the first seven days of every month from July 2016 to June 2017. As results, the mean error of $C_{sat,\;adj}$ (0.61) is less that than that of $C_{sat,\;prev}$ (1.01). The percent of detection for 'Cloudy' scenario of $C_{sat,\;adj}$ (73%) is higher than that of $C_{sat,\;prev}$ (60%) The percent of correction, the accuracy, of $C_{sat,\;adj}$ is 61%, while that of $C_{sat,\;prev}$ is 55% for all seasons. For the December-January-February period when cloudy pixels are readily overestimated, the proportion of correction of $C_{sat,\;adj$ is 60%, while that of $C_{sat,\;prev}$ is 56%. Therefore, we conclude that the present algorithm can effectively get the satellite cloudiness near to the ground-viewed cloudiness.

• The Korean Journal of Nuclear Medicine
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• v.32 no.5
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• pp.414-424
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• 1998

Purpose: Cross-modality coregistration of positron emission tomography (PET) and magnetic resonance imaging (MR) could enhance the clinical information. In this study we propose a refined technique to improve the robustness of registration, and to implement more realistic visualization of the coregistered images. Materials and Methods: Using the sinogram of PET emission scan, we extracted the robust head boundary and used boundary-enhanced PET to coregister PET with MR. The pixels having 10% of maximum pixel value were considered as the boundary of sinogram. Boundary pixel values were exchanged with maximum value of sinogram. One hundred eighty boundary points were extracted at intervals of about 2 degree using simple threshold method from each slice of MR images. Best affined transformation between the two point sets was performed using least square fitting which should minimize the sum of Euclidean distance between the point sets. We reduced calculation time using pre-defined distance map. Finally we developed an automatic coregistration program using this boundary detection and surface matching technique. We designed a new weighted normalization technique to display the coregistered PET and MR images simultaneously. Results: Using our newly developed method, robust extraction of head boundary was possible and spatial registration was successfully performed. Mean displacement error was less than 2.0 mm. In visualization of coregistered images using weighted normalization method, structures shown in MR image could be realistically represented. Conclusion: Our refined technique could practically enhance the performance of automated three dimensional coregistration.

• Journal of Intelligence and Information Systems
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• v.15 no.4
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• pp.1-22
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• 2009

The World Wide Web is transitioning from being a mere collection of documents that contain useful information toward providing a collection of services that perform useful tasks. The emerging Web service technology has been envisioned as the next technological wave and is expected to play an important role in this recent transformation of the Web. By providing interoperable interface standards for application-to-application communication, Web services can be combined with component based software development to promote application interaction and integration both within and across enterprises. To make Web services for service-oriented computing operational, it is important that Web service repositories not only be well-structured but also provide efficient tools for developers to find reusable Web service components that meet their needs. As the potential of Web services for service-oriented computing is being widely recognized, the demand for effective Web service discovery mechanisms is concomitantly growing. A number of techniques for Web service discovery have been proposed, but the discovery challenge has not been satisfactorily addressed. Unfortunately, most existing solutions are either too rudimentary to be useful or too domain dependent to be generalizable. In this paper, we propose a Web service organizing framework that combines clustering techniques with string matching and leverages the semantics of the XML-based service specification in WSDL documents. We believe that this is one of the first attempts at applying data mining techniques in the Web service discovery domain. Our proposed approach has several appealing features : (1) It minimizes the requirement of prior knowledge from both service consumers and publishers; (2) It avoids exploiting domain dependent ontologies; and (3) It is able to visualize the semantic relationships among Web services. We have developed a prototype system based on the proposed framework using an unsupervised artificial neural network and empirically evaluated the proposed approach and tool using real Web service descriptions drawn from operational Web service registries. We report on some preliminary results demonstrating the efficacy of the proposed approach.

• Korean Journal of Remote Sensing
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• v.39 no.6_1
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• pp.1211-1224
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• 2023

Clouds cause many difficult problems in observing land surface phenomena using optical satellites, such as national land observation, disaster response, and change detection. In addition, the presence of clouds affects not only the image processing stage but also the final data quality, so it is necessary to identify and remove them. Therefore, in this study, we developed a new cloud detection technique that automatically performs a series of processes to search and extract the pixels closest to the spectral pattern of clouds in satellite images, select the optimal threshold, and produce a cloud mask based on the threshold. The cloud detection technique largely consists of three steps. In the first step, the process of converting the Digital Number (DN) unit image into top-of-atmosphere reflectance units was performed. In the second step, preprocessing such as Hue-Value-Saturation (HSV) transformation, triangle thresholding, and maximum likelihood classification was applied using the top of the atmosphere reflectance image, and the threshold for generating the initial cloud mask was determined for each image. In the third post-processing step, the noise included in the initial cloud mask created was removed and the cloud boundaries and interior were improved. As experimental data for cloud detection, CAS500-1 L2G images acquired in the Korean Peninsula from April to November, which show the diversity of spatial and seasonal distribution of clouds, were used. To verify the performance of the proposed method, the results generated by a simple thresholding method were compared. As a result of the experiment, compared to the existing method, the proposed method was able to detect clouds more accurately by considering the radiometric characteristics of each image through the preprocessing process. In addition, the results showed that the influence of bright objects (panel roofs, concrete roads, sand, etc.) other than cloud objects was minimized. The proposed method showed more than 30% improved results(F1-score) compared to the existing method but showed limitations in certain images containing snow.

• Journal of Environmental Policy
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• v.13 no.1
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• pp.69-93
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• 2014

The aim of this research was to develop a climate change vulnerability index at the district level (Si, Gun, Gu) with respect to the health care sector in Korea. The climate change vulnerability index was esimated based on the four major causes of climate-related illnesses : vector, flood, heat waves, and air pollution/allergies. The vulnerability assessment framework consists of six layers, all of which are based on the IPCC vulnerability concepts (exposure, sensitivity, and adaptive capacity) and the pathway of direct and indirect impacts of climate change modulators on health. We collected proxy variables based on the conceptual framework of climate change vulnerability. Data were standardized using the min-max normalization method. We applied the analytic hierarchy process (AHP) weight and aggregated the variables using the non-compensatory multi-criteria approach. To verify the index, sensitivity analysis was conducted by using another aggregation method (geometric transformation method, which was applied to the index of multiple deprivation in the UK) and weight, calculated by the Budget Allocation method. The results showed that it would be possible to identify the vulnerable areas by applying the developed climate change vulnerability assessment index. The climate change vulnerability index could then be used as a valuable tool in setting climate change adaptation policies in the health care sector.

• Journal of the Economic Geographical Society of Korea
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• v.19 no.2
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• pp.360-377
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• 2016

Since after the 1986 economic reform policy(Doi Moi), the central highland in Vietnam has transformed into one of the largest coffee producing areas. The transformation had been supported by mass migration of ethnic Kinhs from the coastal lowland. It did not take long for the Kinh migrants to be the ethnic majority in the region. Meanwhile the growth of coffee industry entailed in socio-economic disparity, specially between Kinh migrants and native ethnic minorities. The disparity has becomed obvious not only between coffee farming Kinhs and non-coffee farming ethnic minorities but also between coffee farming Kinhs and ehtnic minorities. The previous literatures highlight the lack of human and social capital and the lagging modernization in ethnic minority societies. However, they fall short in showing the explicit processes why ethnic minority coffee farmers earn less than ethnic majority counterparts. With a case study of Dak Lak province, this research attempts to show the reason why there is income gap between Kinh and ethnic minority Ede coffee farmers by comparing their ways of producing coffee and selling their products. The results show that Ede's land productivity is significantly lower than Kinh's. It is because Ede farmers use less fertilizer due to the shortage of the capital. Also they often get into debt for coffee production and should pay it back right after the harvest. It deprives them of chance to raise earning by selling the coffee beans at a higher price.

• Journal of Plant Biotechnology
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• v.41 no.2
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• pp.81-88
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• 2014

Salt cress (Thellungiella halophila or Thellungiella parvula), species closely related to Arabidopsis thaliana, represents an extremophile adapted to harsh saline environments. To isolate salt-tolerance genes from this species, we constructed a cDNA library from roots and leaves of salt cress plants treated with 200 mM NaCl. This cDNA library was subsequently shuttled into the destination binary vector [driven by the cauliflower mosaic virus (CaMV) 35S promoter] designed for plant transformation and expression via recombination- assisted cloning. In total, 305,400 pools of transgenic BASTA-resistant lines were generated in Arabidopsis using either T. halophila or T. parvula cDNA libraries. These were used for functional screening of genes involved in salt tolerance. Among these pools, 168,500 pools were used for primary screening to date from which 7,157 lines showed apparent salt tolerant-phenotypes in the initial screen. A secondary screen has now identified 165 salt tolerant transgenic lines using 1,551 (10.6%) lines that emerged in the first screen. The prevalent phenotype in these lines includes accelerated seed germination often accompanied by faster root growth compared to WT Arabidopsis under salt stress condition. In addition, other lines showed non-typical development of stems and flowers compared to WT Arabidopsis. Based on the close relationship of the tolerant species to the target species we suggest this approach as an appropriate method for the large-scale identification of salt tolerance genes from salt cress.

• Korean Journal of Remote Sensing
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• v.31 no.6
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• pp.531-548
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• 2015

Atmospheric Motion Vector (AMV) from satellite images have shown Slow Speed Bias (SSB) in comparison with rawinsonde. The causes of SSB are originated from tracking, selection, and height assignment error, which is known to be the leading error. However, recent works have shown that height assignment error cannot be fully explained the cause of SSB. This paper attempts a new approach to examine the possibility of SSB reduction of COMS AMV by using a new target tracking algorithm. Tracking error can be caused by averaging of various wind patterns within a target and changing of cloud shape in searching process over time. To overcome this problem, Gaussian Mixture Model (GMM) has been adopted to extract the coldest cluster as target since the shape of such target is less subject to transformation. Then, an image filtering scheme is applied to weigh more on the selected coldest pixels than the other, which makes it easy to track the target. When AMV derived from our algorithm with sum of squared distance method and current COMS are compared with rawindsonde, our products show noticeable improvement over COMS products in mean wind speed by an increase of $2.7ms^{-1}$ and SSB reduction by 29%. However, the statistics regarding the bias show negative impact for mid/low level with our algorithm, and the number of vectors are reduced by 40% relative to COMS. Therefore, further study is required to improve accuracy for mid/low level winds and increase the number of AMV vectors.

• Korean Journal of Breeding Science
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• v.50 no.4
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• pp.463-471
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• 2018

Perilla is an oilseed crop cultivated in Korea since ancient times. Due to the high ${\alpha}-linolenic$ acid content in perilla, perilla seed oil can easily become rancid. ${\alpha}-Linolenic$ acid is synthesized by two enzymes, endoplasmic reticulum-localized ${\Delta}15$ desaturase (FAD3) and chloroplast-localized ${\Delta}15$ desaturase (FAD7) in vivo. In order to lower the ${\alpha}-linolenic$ acid content of the seed oil without disturbing plant growth, we tried to suppress the expression of only the FAD3 gene using RNA interference, whilst maintaining the expression of the FAD7 gene. Seventeen transgenic plants with herbicide ($Basta^{TM}$) resistance were obtained by Agrobacterium-mediated transformation using hypocotyls of perilla plants. The transgenic plants were firstly confirmed by treatment with 0.3% (v/v) $Basta^{TM}$ herbicide, and the expression of FAD3 was measured by Northern blot analysis. The ${\alpha}-linolenic$ acid content was 10-20%, 30-40%, and 60% in two, seven, and three of the twelve $T_1$ transgenic perilla plants which had enough seeds to be analyzed for fatty acid composition, respectively. Analysis of the fatty acid composition of $T_2$ progeny seeds from $T_1$ plants with the lowest ${\alpha}-linolenic$ acid content showed that the homozygous lines had 6-10% ${\alpha}-linolenic$ acid content and the heterozygous lines had 20-26% ${\alpha}-linolenic$ acid content. It is expected that the reduction in ${\alpha}-linolenic$ acid content in perilla seed oil will prevent rancidity and can be utilized for the production of high-value functional ingredients such as high ${\gamma}-linolenic$ acid.

• Korean Journal of Heritage: History & Science
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• v.57 no.1
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• pp.198-216
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• 2024

This article reevaluates the National Museum of Korea's pivotal actions during the Korean War in the 1950s and its aftermath. It argues that the evacuation of the museum's collection to Busan and the subsequent exhibition "Masterpieces of Korean Art" in the United States in 1957 were not isolated events, but rather interconnected facets of a larger narrative shaping the museum's trajectory. With newly discovered archival evidence, this study unravels the intricate relationship between these episodes, revealing how the initial Busan evacuation evolved into a strategic U.S.-led touring exhibition. Traditionally, the Busan evacuation has been understood solely as a four-stage relocation of the museum's collections between December 1950 and May 1951. However, this overlooks the broader context, particularly the subsequent U.S. journey. Driven by the war's initial retreat of the war, the Busan evacuation served as a stepping stone for evacuation to Honolulu Museum of Art. The path of evacuation took an unexpected turn when the government redirected the collections to the Honolulu Museum of Art. Initially conceived as a storage solution, public opposition led to a remarkable transformation: the U.S. exhibition. To address public concerns, the evacuation plan was canceled. This shift transformed the planned introduction into a full-fledged traveling exhibition. Subsequently approved by the National Assembly, the U.S. Department of State spearheaded development of the exhibition, marking a distinct strategic cultural policy shift for Korea. Therefore, the Busan evacuation, initially envisioned as a temporary introduction to the U.S., ultimately metamorphosed into a multi-stage U.S. touring exhibition orchestrated by the U.S. Department of State. This reframed narrative sheds new light on the museum's crucial role in navigating a complex postwar landscape, revealing the intricate interplay between cultural preservation, public diplomacy, and strategic national interests.