• Korean Journal of Remote Sensing
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• v.25 no.1
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• pp.45-59
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• 2009

This research presents the effect of Asian dust on the derived sea surface temperature (SST) from measurements of the Advanced Very High Resolution Radiometer (AVHRR) instrument flown onboard NOAA polar orbiting satellites. To analyze the effect, A VHRR infrared brightness temperature (TB) is estimated from simulated radiance calculated from radiative transfer model on various atmospheric conditions. Vertical profiles of temperature, pressure, and humidity from radiosonde observation are used to build up the East Asian atmospheric conditions in spring. Aerosol optical thickness (AOT) and size distribution are derived from skyradiation measurements to be used as inputs to the radiative transfer model. The simulation results show that single channel TB at window region is depressed under the Asian dust condition. The magnitude of depression is about 2K at nadir under moderate aerosol loading, but the magnitude reaches up to 4K at slant path. The dual channel difference (DCD) in spilt window region is also reduced under the Asian dust condition, but the reduction of DCD is much smaller than that shown in single channel TB simulation. Owing to the depression of TB, SST has cold bias. In addition, the effect of AOT on SST is amplified at large satellite zenith angle (SZA), resulting in high variance in derived SSTs. The SST depression due to the presence of Asian dust can be expressed as a linear function of AOT and SZA. On the basis of this relationship, the effect of Asian dust on the SST retrieval from the conventional daytime multi-channel SST algorithm can be derived as a function of AOT and SZA.

• Korean Journal of Remote Sensing
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• v.22 no.6
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• pp.507-518
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• 2006

The radiation at $11{\mu}m$ absorbed more than at $12{\mu}m$ when aerosols is loaded in the atmosphere, whereas it will be the other way around when cloud is present. The difference of the two channels provides an opportunity to detect aerosols such as Yellow Sand even with the presence of clouds and at night. However problems associated with this approach arise because the difference can be affected by various atmospheric and surface conditions. In this paper, we has analyzed how the threshold and sensitivity of the brightness temperature difference between two channel (BTD) vary with respect to the conditions in detail. The important finding is that the threshold value for the BTD distinguishing between aerosols and cloud is $0.8^{\circ}K$ with the US standard atmosphere, which is greater than the typical value of $0^{\circ}K$. The threshold and sensitivity studies for the BTD show that solar zenith angle, aerosols altitude, surface reflectivity, and atmospheric temperature profile marginally affect the BTD. However, satellite zenith angle, surface temperature along with emissivity, and vertical profile of water vapor are strongly influencing on the BTD, which is as much as of about 50%. These results strongly suggest that the aerosol retrieval with the BTD method must be cautious and the outcomes must be carefully calibrated with respect to the sources of the error.

• The Journal of the Korea Contents Association
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• v.19 no.10
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• pp.217-225
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• 2019

National research and development(R&D) information is information generated in the process of performing R&D based on programs and projects issued by national government departments, and includes information from various research fields as ordered by various departments. Therefore, for efficient R&D information retrieval, it is necessary to build a national R&D terminology dictionary that can reflect the characteristics of such national R&D information. In this study, we propose a method for constructing a national R&D terminology dictionary by applying the classification of science and technology standards used to specify the research field in national R&D information. We will discuss the structural characteristics of national R&D project information and the usefulness of the project keyword, and explain the status of national R&D information by the National Standard Science and Technology Classification(NSSTC) Codes and the characteristics of the national R&D terminologies. Based on this, a method for building a national R&D terminology dictionary is defined in terms of the type and structure of the terminology dictionary, preliminary construction procedures, and refining rules. The national R&D terminology dictionary built on the basis of this study can be used in various ways such as expansion of search terms using Korean-English equivalent words and synonyms when searching national R&D information, clarifying the scope of search using NSSTC, and providing user convenience functions using term explanation information.

• Journal of the Korean earth science society
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• v.40 no.5
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• pp.502-517
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• 2019

Global warming and rapid climate change have long affected the characteristics of typhoons in the Northwest Pacific, which has induced increasing devastating disasters along the coastal regions of the Korean peninsula. Synthetic Aperature Radar (SAR), as one of the microwave sensors, makes it possible to produce high-resolution sea surface wind field around the typhoon under cloudy atmospheric conditions, which has been impossible to obtain the winds from satellite optical and infrared sensors. The Geophysical Model Functions (GMFs) for sea surface wind retrieval from SAR data requires the input of wind direction, which should be based on the accurate estimation of the center of the typhoon. This study estimated the typhoon centers using Sentinel-1A images to improve the problem of typhoon center detection method and to reflect it in retrieving the sea surface wind. The results were validated by comparing with the typhoon best track data provided by the Korea Meteorological Administration (KMA) and Japan Meteorological Agency (JMA), and also by using infrared images of Himawari-8 satellite. The initial center position of the typhoon was determined by using VH polarization, thereby reducing the possibility of error. The detected center showed a difference of 23.76 km on average with the best track data of the four typhoons provided by the KMA and JMA. Compared to the typhoon center estimated by Himawari-8 satellite, the results showed an average spatial variation of 11.80 km except one typhoon located near land with a large difference of 58.73 km. This result suggests that high-resolution SAR images can be used to estimate the center and retrieve sea surface wind around typhoons.

• Korean Journal of Clinical Laboratory Science
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• v.53 no.4
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• pp.353-362
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• 2021

Cancer is a global health problem. There are diverse types of cancers, but there are several common pathways which lead to the development of cancer. Changes in gene expression might be the most common similarity found in almost all cancers. An understanding of the underlying changes in gene expression during cancer progression could lay a valuable foundation for the development of cancer therapeutics and even cancer vaccines. In this study, a well-known carcinogen, N-methyl-N'-nitro-N-nitrosoguanidine (MNNG), was employed to induce changes in gene expression in normal stomach cells. MNNG is known to cause cancer by inducing damage to DNA in MNNG-treated mammalian cells and animals fed with this carcinogen. An analysis was performed by comparing the differentially expressed genes (DEGs) caused by MNNG treatment with DEGs in stomach cancer cell lines. To this end, methods of analysis for functional categorization and protein-protein interaction networks, such as gene ontology (GO), the database for annotation, visualization, and integrated discovery (DAVID), Kyoto encyclopedia of genes and genomics (KEGG) and search tool for the retrieval of interacting genes/proteins (STRING), were used. As a result of these analyses, MNNG-regulated specific genes and interaction networks of their protein products that contributed to stomach cancer were identified.

• 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.

• Journal of the Korean Society for information Management
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• v.38 no.3
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• pp.73-99
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• 2021

The purpose of this study is to analyze the health information use experience of middle-aged people in their 40s and 50s and to observe and analyze their health information search behaviors according to health consciousness and health information orientation. This study uses Information Foraging Theory with the concept of information scents which leads users to detect and collect cues in information searching. Types and contents of information cues that middle-aged people use when searching for health information were investigated. Also, how their health consciousness and health information orientation affected using information cues were analyzed. Three methods of research were used; (1) pre-interviews, (2) search experiments, and (3) post-interviews. Thirty-two middle-aged people participated in the study. Their performance on health information searching was recorded and referred to in the post-interviews using a think-aloud protocol. Findings presented that middle-aged people's health consciousness and health information orientation affected the perception of information scents in health information search; those with high health consciousness and health information orientation consider the text made by the government office the most critical information cues. We believe findings from this study could be used for public libraries or non-profit institutions to understand middle-aged people's health information behaviors to design education programs for information retrieval considering users' health consciousness and health information orientation. Findings could also contribute to Internet portal site or health-related web site designers developing strategies for middle-aged users to access health information effectively.

• Korean Journal of Remote Sensing
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• v.37 no.6_1
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• pp.1697-1707
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• 2021

On 19 February 2020, the 2nd Geostationary Ocean Color Imager (GOCI-II), a maritime sensor of GEO-KOMPSAT-2B, was launched. The GOCI-II instrument expands the scope of aerosol retrieval research with its improved performance compared to the former instrument (GOCI). In particular, the newly included UV band at 380 nm plays a significant role in improving the sensitivity of GOCI-II observations to the absorbing aerosols. In this study, we calculated the aerosol index and detected absorbing aerosols from January to June 2021 using GOCI-II 380 and 412 nm channels. Compared to the TROPOMI aerosol index, the GOCI-II aerosol index showed a positive bias, but the dust pixels still could be clearly distinguished from the cloud and clear pixels. The high GOCI-II aerosol index coincided with ground-based observations indicating dust aerosols were detected. We found that 70.5% of dust and 80% of moderately-absorbing fine aerosols detected from the ground had GOCI-II aerosol indices larger than the 75th percentile through the whole study period.

• Journal of the Korea Convergence Society
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• v.12 no.12
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• pp.93-106
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• 2021

Blenderbot 2.0 is a dialogue model representing open domain chatbots by reflecting real-time information and remembering user information for a long time through an internet search module and multi-session. Nevertheless, the model still has many improvements. Therefore, this paper analyzes the limitations and errors of BlenderBot 2.0 from three perspectives: model, data, and dialogue. From the data point of view, we point out errors that the guidelines provided to workers during the crowdsourcing process were not clear, and the process of refining hate speech in the collected data and verifying the accuracy of internet-based information was lacking. Finally, from the viewpoint of dialogue, nine types of problems found during conversation and their causes are thoroughly analyzed. Furthermore, practical improvement methods are proposed for each point of view, and we discuss several potential future research directions.

• Health Communication
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• v.12 no.1
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• pp.73-84
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• 2017

Purpose: As the internet use of teenagers become more common, the need for research on the relationship between the internet and youth depression has emerged. The purpose of this study is to investigate the relationship between internet use and adolescent depression. Methods: The subjects of this study were youth attending elementary($6^{th}$ grade), middle($2^{nd}$ grade), and high schools($2^{nd}$ grade) belonging to the Busan Metropolitan City Office of Education. Depression was assessed using the BDI depression scale. Internet functions were classified into 10 categories, and the degree of use by Internet functions was examined. The most frequently used Internet sites were surveyed. Univariate analysis using $X^2$ test and multivariate analysis using logistic regression analysis were conducted to find out the difference of internet and smartphone media function on depression according to elementary, middle and high school students. Results: Depression was higher of 13.2 times for students who use online transactions (goods purchase), 0.07 times for students who use 'bulletin board' activities in elementary students. Depression was higher of 1.55 times for those who use online transactions (purchasing goods), and 2.3 times for those who use adult sites for middle school students. Depression was higher of 2.1 times when using e-mail and 1.9 times when using other information retrieval for high school students. Conclusion: It is necessary to consider characteristics of internet utilizing pattern by school class in policy regulation and prevention program to reduce youth depression.