• Korean Journal of Agricultural and Forest Meteorology
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• v.17 no.4
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• pp.281-289
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• 2015

Information on sunshine duration and solar radiation are indispensable to the understanding of crop growth and development. Yet, relevant variables are not available in the Korea Meteorological Administration's (KMA) digital forecast. We proposed the methods of estimating sunshine duration and solar radiation based on the 'sky condition' of digital forecast products and validated using the observed data. The sky condition values (1 for clear, 2 for partly cloudy, 3 for cloudy, and 4 for overcast) were collected from 22 weather stations at 3-hourly intervals from August 2013 to July 2015. According to the observed relationship, these data were converted to the corresponding amount of clouds on the 0 to 10 scale (0 for clear, 4 for partly cloudy, 7 for cloudy, and 10 for overcast). An equation for the cloud amount-sunshine duration conversion was derived from the 3-year observation data at three weather stations with the highest clear day sunshine ratio (i.e., Daegwallyeong, Bukgangneung, and Busan). Then, the estimated sunshine hour data were used to run the Angstrom-Prescott model which was parameterized with the long-term KMA observations, resulting in daily solar radiation for the three weather stations. Comparison of the estimated sunshine duration and solar radiation with the observed at those three stations showed that the root mean square error ranged from 1.5 to 1.7 hours for sunshine duration and from 2.5 to $3.0MJ\;m^{-2}\;day^{-1}$ for solar radiation, respectively.

• Journal of Broadcast Engineering
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• v.13 no.4
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• pp.544-553
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• 2008

With the development of video editing technology, there are growing uses of overlay text inserted into video contents to provide viewers with better visual understanding. Since the content of the scene or the editor's intention can be well represented by using inserted text, it is useful for video information retrieval and indexing. Most of the previous approaches are based on low-level features, such as edge, color, and texture information. However, existing methods experience difficulties in handling texts with various contrasts or inserted in a complex background. In this paper, we propose a novel framework to localize the overlay text in a video scene. Based on our observation that there exist transient colors between inserted text and its adjacent background a transition map is generated. Then candidate regions are extracted by using the transition map and overlay text is finally determined based on the density of state in each candidate. The proposed method is robust to color, size, position, style, and contrast of overlay text. It is also language free. Text region update between frames is also exploited to reduce the processing time. Experiments are performed on diverse videos to confirm the efficiency of the proposed method.

• Journal of Service Research and Studies
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• v.13 no.4
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• pp.191-205
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• 2023

Artificial Intelligence (AI), especially in the domain of text-generative services, has witnessed a significant surge, with forecasts indicating the AI-as-a-Service (AIaaS) market reaching a valuation of $55.0 Billion by 2028. This research set out to explore the quality dimensions characterizing synthetic text media software, with a focus on four key players in the industry: ChatGPT, Writesonic, Jasper, and Anyword. Drawing from a comprehensive dataset of over 4,000 reviews sourced from a software evaluation platform, the study employed the Latent Dirichlet Allocation (LDA) topic modeling technique using the Gensim library. This process resulted the data into 11 distinct topics. Subsequent analysis involved comparing these topics against established AI service quality dimensions, specifically AICSQ and AISAQUAL. Notably, the reviews predominantly emphasized dimensions like availability and efficiency, while others, such as anthropomorphism, which have been underscored in prior literature, were absent. This observation is attributed to the inherent nature of the reviews of AI services examined, which lean more towards semantic understanding rather than direct user interaction. The study acknowledges inherent limitations, mainly potential biases stemming from the singular review source and the specific nature of the reviewer demographic. Possible future research includes gauging the real-world implications of these quality dimensions on user satisfaction and to discuss deeper into how individual dimensions might impact overall ratings.

• Korean Journal of Remote Sensing
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• v.37 no.6_1
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• pp.1767-1772
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• 2021

Global satellite observation surface albedo data over a long period of time are actively used to monitor changes in the global climate and environment, and their utilization and importance are great. Through the generational shift of geostationary satellites COMS (Communication, Ocean and Meteorological Satellite)/MI (Meteorological Imager sensor) and GK-2A (GEO-KOMPSAT-2A)/AMI (Advanced Meteorological Imager sensor), it is possible to continuously secure surface albedo outputs. However, the surface albedo outputs of COMS/MI and GK-2A/AMI differ between outputs due to Differences in retrieval algorithms. Therefore, in order to expand the retrieval period of the surface albedo of COMS/MI and GK-2A/AMI to secure continuous climate change monitoring linkage, the analysis of the two satellite outputs and errors should be preceded. In this study, error characteristics were analyzed by performing comparative analysis with ground observation data AERONET (Aerosol Robotic Network) and other satellite data GLASS (Global Land Surface Satellite) for the overlapping period of COMS/MI and GK-2A/AMI surface albedo data. As a result of error analysis, it was confirmed that the RMSE of COMS/MI was 0.043, higher than the RMSE of GK-2A/AMI, 0.015. In addition, compared to other satellite (GLASS) data, the RMSE of COMS/MI was 0.029, slightly lower than that of GK-2A/AMI 0.038. When understanding these error characteristics and using COMS/MI and GK-2A/AMI's surface albedo data, it will be possible to actively utilize them for long-term climate change monitoring.

• Atmosphere
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• v.20 no.1
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• pp.37-47
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• 2010

The methods measuring the precipitation drop size distribution(hereafter referred to as DSD) at Cloud Physics Observation System (CPOS) in Daegwallyeong are to use PARSIVEL (PARticle SIze and VELocity) disdrometer (hereafter referred to as PARSIVEL) and Micro Rain Radar (hereafter referred to as MRR). First of all, PARSIVEL and MRR give good correlation coefficients between their rain rates and those of rain gage: $R^2=0.93$ and 0.91, respectively. For the DSD, the rain rates are classified in 3 categories (Category 1: rr (Rain Rate) ${\leq}0.5\;mm\;h^{-1}$, Category 2: $0.5\;mm\;h^-1$ < rr < $4.0\;mm\;h^{-1}$, Category 3: rr ${\geq}4\;mm\;h^{-1}$). The shapes of PARSIVEL and MRR DSD are relatively most similar in category 2. In addition, we retrieve the vertical rain rate and liquid water content from MRR under melting layer, calculated by Cha et al's method, in Daegwallyeong ($37^{\circ}41{\prime}N$, $128^{\circ}45^{\prime}E$, 843 m ASL, mountain area) and Haenam ($34^{\circ}33^{\prime}N$, $126^{\circ}34^{\prime}E$, 4.6 m ASL, coast area). The vertical variations of rain rate and liquid water content in Daegwallyeong are smaller than those in Haenam. We think that this different vertical rain rate characteristic for both sites is due to the vertical different cloud type (convective and stratiform cloud seem dominant at Haenam and Daegwallyeong, respectively). This suggests that the statistical precipitation DSD model, for the application of weather radar and numerical simulation of precipitation processes, be considered differently for the region, which will be performed in near future.

• Proceedings of KOSOMES biannual meeting
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• 2006.11a
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• pp.193-199
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• 2006

This article reviews several microwave instruments employed in observation and analysis of tropical cyclones (TCs), typhoon, and hurricanes. Microwave signals are useful for observing tropical cyclones with severe storms since it isn't severely absorbed by the clouds and rain in the storm. The instruments discussed include scatterometers, microwave radiometers, synthetic aperture radars (SARs), and rain radar from space. The date such as winds, rainfall and cloud-distribution in the TCs obtained by microwave instruments provide important informations for forecasting the intensity and path of the typhoon. For example, there're wind-distribution provided by SSM/I which has a wide swath, detailed wind fields from ERS-1, 2 scatterometers and RADARSAT-1 SAR and TRMM's rain radar pro 떠 ding high resolution. Operational satellite instruments lunched recently have improved upon the problems of low resolution and narrow swath indicated at the beginning microwave remote sensing. Understanding and practical using sufficiently about the microwave instruments will serve for searching the features such as generation and development of the TCs.

• Journal of the Korean earth science society
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• v.42 no.1
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• pp.88-101
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• 2021

The purpose of this study was to qualitatively examine the meaning of students' drawings in outdoor classes and modeling-based learning cycles. Ten students were observed in a gifted education center in Seoul. Under the theme of the Hantan River, three outdoor classes and three modeling activities were conducted. Data were collected to document all student activities during field trips and classroom modeling activities using simultaneous video and audio recording and observation notes made by the researcher and students. Please note it is unclear what this citation refers to. If it is the previous sentence it should be placed within that sentence's punctuation. Hatisaru (2020) Ddrawing typess were classified by modifying the representations in a learning context in geological field trips. We used deductive content analysis to describe the drawing characteristics, including students writing. The results suggest that students have symbolic images that consist of geologic concepts, visual images that describe topographical features, and affective images that express students' emotion domains. The characteristics were classified into explanation, generality, elaboration, evidence, coherence, and state-of-mind. The characteristics and drawing types are consecutive in the modeling-based learning cycle and reflect the students' positive attitude and cognitive scientific domain. Drawing is a useful tool for reflecting students' thoughts and opinions in both outdoor class and classroom modeling activities. This study provides implications for emphasizing the importance of drawing activities.

• Communications of Mathematical Education
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• v.35 no.4
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• pp.527-546
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• 2021

The purpose of this study is to reveal what mathematics teachers focus on and how they assess students' thinking during lessons enacted. For this purpose, we googled and searched internet sites to collect formative assessment materials for the year 2014 to 2019. The formative assessment tasks data were analyzed according to the levels cognitive demand levels and tasks suggested in textbooks in terms of degrees to which how they are related. The data analysis suggested as follows: a) most of the formative assessment tasks were at the low-level, in particular, PNC level tasks that require applying particular procedures without connections to concepts and meaning underlying the procedures, b) the assessment tasks appeared to be very similar to the tasks suggested in the secondary mathematics textbooks, and c) it seemed that 3 types of formative assessment, observation notes, self-assessment, and peer-assessment were dominantly utilized during mathematics lessons and these different types of formative assessment were employed apparently to find out whether students participated actively in class and in group activity, not how they go through understanding or thinking processes.

• Journal of The Korean Association For Science Education
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• v.29 no.1
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• pp.54-67
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• 2009

This study dealt with two case studies of the development of beginning science teachers' pedagogical content knowledge (PCK). This study was grounded on the idea that teacher thinking and classroom behavior are related to each other in a reciprocal way. Teachers' PCK influences teaching practices, while in a reverse way teaching activities influence teachers' practical knowledge. Two beginning science teachers participated in this study. Data collection consisted of classroom observation, interviews, reflective journals and lesson plans. For data analysis, we conceptualize pedagogical content knowledge for science teaching as consisting of four components: (a) knowledge about science matter, (b) knowledge about students' understanding of science topics, (c) knowledge about instructional strategies for teaching science, (d) knowledge about assessment in science. The outcomes of this study revealed that there was a large gap between beginning science teachers' intentions for teaching science and their practice. To give beginning teachers more opportunities to incorporate their knowledge base for teaching, we propose that they need to be involved in a real teaching situation at schools rather than in the university.

• Journal of the Korean Institute of Landscape Architecture
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• v.42 no.1
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• pp.1-17
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• 2014

The Practice of Landscape Urbanism has been criticized on two aspects; Landscape Urbanism does not yet provide differentiated forms of planning and design neither able to fill the gap between theory and practice. In response to these criticisms, Landscape Urbanists have tried to provide additional cases that can exemplify achievements of Landscape Urbanism in practice. There has been another type of effort to suggest distinct planning and design strategies of Landscape Urbanism from theoretical texts. However, these approaches overlooked the fact that professional practice actually gave huge influence on the theoretical framework of Landscape Urbanism. Based on this observation, the study examined the development process of Landscape Urbanism by verifying the correlation between its practice and theory. Through an extensive literature review, the study suggested horizontality, infrastructure, process, ecology, media, hybrid, site, and scale as eight major concepts of Landscape Urbanism. Afterwards, the study classified 51 projects cited in major essays and articles of Landscape Urbanism into four categories: Archetypal projects, precedent projects, exemplary projects, and progressive projects. The correlation between strategies of the selected projects and main theoretical concepts was analyzed. The study found out that the early stage of the theory was focused on defining and explaining the new design and planning approaches of contemporary design projects related with landscape. However, these days, Landscape Urbanism became a more productive in providing diverse types of practice sharing the direction and vision proposed by the theory. Various projects influenced in constructing theoretical structure of Landscape Urbanism as well as proved that the suggestions of Landscape Urbanism could be effective to reorganize contemporary cites in the form of design and planning strategies. The observation of this study can contribute to provide proper answers to the criticism on practice of Landscape Urbanism and be helpful in understanding the limits and unrealized potentials of Landscape Urbanism as a practical theory.