• Korean Journal of Agricultural and Forest Meteorology
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• v.14 no.1
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• pp.11-18
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• 2012

Daily temperature data produced by harmonic analysis of monthly climate summary have been used as an input to plant phenology model. This study was carried out to evaluate the performance of the harmonic based daily temperature data in prediction of major phenological developments and to apply the results in improving decision support for agricultural production in relation to the climate change scenarios. Daily maximum and minimum temperature data for a climatological normal year (Jan. 1 to Dec. 31, 1971-2000) were produced by harmonic analysis of the monthly climate means for Seoul weather station. The data were used as inputs to a thermal time - based phenology model to predict dormancy, budburst, and flowering of Japanese cherry in Seoul. Daily temperature measurements at Seoul station from 1971 to 2000 were used to run the same model and the results were compared with the harmonic data case. Leaving no information on annual variation aside, the harmonic based simulation showed 25 days earlier release from endodormancy, 57 days longer period for maximum cold tolerance, delayed budburst and flowering by 14 and 13 days, respectively, compared with the simulation based on the observed data. As an alternative to the harmonic data, 30 years daily temperature data were generated by a stochastic process (SIMMETEO + WGEN) using climatic summary of Seoul station for 1971-2000. When these data were used to simulate major phenology of Japanese cherry for 30 years, deviations from the results using observed data were much less than the harmonic data case: 6 days earlier dormancy release, 10 days reduction in maximum cold tolerance period, only 3 and 2 days delay in budburst and flowering, respectively. Inter-annual variation in phenological developments was also in accordance with the observed data. If stochastically generated temperature data could be used in agroclimatic mapping and zoning, more reliable and practical aids will be available to climate change adaptation policy or decision makers.

• Journal of KIISE:Software and Applications
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• v.36 no.2
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• pp.169-177
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• 2009

In this paper, we propose a new shot boundary detection method which is optimized for news video story parsing. This new news shot boundary detection method was designed to satisfy all the following requirements: 1) minimizing the incorrect data in data set for anchor shot detection by improving the recall ratio 2) detecting abrupt cuts and gradual transitions with one single algorithm so as to divide news video into shots with one scan of data set; 3) classifying shots into static or dynamic, therefore, reducing the search space for the subsequent stage of anchor shot detection. The proposed method, based on singular value decomposition with incremental clustering and mercer kernel, has additional desirable features. Applying singular value decomposition, the noise or trivial variations in the video sequence are removed. Therefore, the separability is improved. Mercer kernel improves the possibility of detection of shots which is not separable in input space by mapping data to high dimensional feature space. The experimental results illustrated the superiority of the proposed method with respect to recall criteria and search space reduction for anchor shot detection.

• Journal of Korean Society of Environmental Engineers
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• v.28 no.2
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• pp.150-157
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• 2006

Spatially resolved remote identification and quantification of trace gases in the atmosphere is desirable in various fields of scientific research as well as in public security and industrial contexts. Environmental observations investigating causes, extent md consequences of air pollution are of fundamental interest. We present an Imaging-DOAS system, a ground based remote sensing instrument that allows spatially resolved mapping of atmospheric trace gases by a differential optical absorption spectroscopy(DOAS) with sun scattered light as the light source. A passive DOAS technique permits the identification and quantification of various gases, e.g., $NO_2,\;SO_2,\;and\;CH_2O$, from their differential absorption structures with high sensitivity. The Imaging-DOAS system consists of a scanning mirror, a focusing lens, a spectrometer, a 2-D CCD, ad the integral control software. An imaging spectrometer simultaneously acquires spectral information on the incident light in one spatial dimension(column) and sequentially scans the next spatial dimension with a motorized scanning mirror. The structure of the signal acquisition system is described in detail and the evaluation method is also briefly discussed. Applications of imaging of the $NO_2$ contents in the exhaust plumes from a power plant are presented.

• Journal of KIISE:Databases
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• v.34 no.6
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• pp.528-545
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• 2007

Recently ontology has been an attractive technology along with the business strategy of providing a plenty of more intelligent services. The essential problem in application domains using ontology is that all members, agents, and application programs in the domains must share the same ontology concepts. However, a variety of mobile devices, sensing devices, and network components manufactured by various companies, a variety of common carriers, and a variety of contents providers make multiple heterogeneous ontologies more likely to coexist. We can see many past researches fallen into resolving this semantic interoperability. Such methods can be broadly classified into by-mapping, by-merging, and by-translation. In this research, we focus on by-translation among them which uses a translation rule directly made between two heterogeneous ontology data like OntoMorph. However, the manual composition of the direct translation rule is not convenient by itself and if there are N ontologies, the direct method has the rule composition complexity of $O(N^2)$ in the worst case. Therefore, in this paper we introduce the cascade composition of translation rules based on web openness in order to improve the complexity. The research result made us recognize some important factors in an ontology translation system, that is speediness of translation, and conveniency of translation rule composition, and some experiments and comparing analysis with existing methods showed that our cascade method has more conveniency with insuring the speediness and the correctness.

• Korean Journal of Cognitive Science
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• v.12 no.1_2
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• pp.77-89
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• 2001

Applying perceptual hierarchy of facial feature points, a neural network model for recognizing facial expressions was designed. Input data were convolution values of 150 facial expression pictures by Gabor-filters of 5 different sizes and 8 different orientations for each of 39 mesh points defined by MPEG-4 SNHC (Synthetic/Natural Hybrid Coding). A set of multiple regression analyses was performed with the rating value of the affective states for each facial expression and the Gabor-filtered values of 39 feature points. The results show that the pleasure-displeasure dimension of affective states is mainly related to the feature points around the mouth and the eyebrows, while a arousal-sleep dimension is closely related to the feature points around eyes. For the filter sizes. the affective states were found to be mostly related to the low spatial frequency. and for the filter orientations. the oblique orientations. An optimized neural network model was designed on the basis of these results by reducing original 1560(39x5x8) input elements to 400(25x2x8) The optimized model could predict human affective rating values. up to the correlation value of 0.886 for the pleasure-displeasure, and 0.631 for the arousal-sleep. Mapping the results of the optimized model to the six basic emotional categories (happy, sad, fear, angry, surprised, disgusted) fit 74% of human responses. Results of this study imply that, using human principles of recognizing facial expressions, a system for recognizing facial expressions can be optimized even with a a relatively little amount of information.

• Journal of KIISE:Computer Systems and Theory
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• v.29 no.5
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• pp.245-256
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• 2002

Shadows are important elements in producing a realistic image. Generation of exact shapes and positions of shadows is essential in rendering since it provides users with visual cues on the scene. It is also very important to be able to create soft shadows resulted from area light sources since they increase the visual realism drastically. In spite of their importance. the existing shadow generation algorithms still have some problems in producing realistic shadows in real-time. While image-based rendering techniques can often be effective1y applied to real-time shadow generation, such techniques usually demand so large memory space for storing preprocessed shadow maps. An effective compression method can help in reducing memory requirement, only at the additional decoding costs. In this paper, we propose a new image-barred shadow generation method based on image warping. With this method, it is possible to generate realistic shadows using only small sizes of pre-generated shadow maps, and is easy to extend to soft shadow generation. Our method will be efficiently used for generating realistic scenes in many real-time applications such as 3D games and virtual reality systems.

• Journal of Korean Society for Atmospheric Environment
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• v.26 no.1
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• pp.10-20
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• 2010

In recent studies, $PM_{2.5}$ has been reported to be more harmful to human health than $PM_{10}$ because it penetrates more deeply into the lung. We estimated $PM_{2.5}$ related health benefits in Seoul from implementing the World Health Organization (WHO)'s guidelines (annual average $10{\mu}g/m^3$, 24-hour average $25{\mu}g/m^3$) and U.S. Environmental Protection Agency (EPA)'s National Ambient Air Quality Standard (annual average $15{\mu}g/m^3$, 24-hour average $35{\mu}g/m^3$). U.S. EPA's Environmental Benefits Mapping and Analysis Program was utilized for the analysis. It was predicted that the attainment of the WHO annual guideline and U.S. EPA's annual standard, relative to the concentration in 2006, would result in reduction of 2,333~2,895 premature deaths and 1,703~2,121 premature deaths, respectively. If the WHO and EPA's daily standard for $PM_{2.5}$ are attained, 1,211~1,394 and 1,012~1,165 premature deaths could be avoided, respectively. Sensitivity analyses indicated that the estimates were robust regardless of air quality simulation methods for attaining the $PM_{2.5}$ goals. This study provides a quantitative approach to evaluate health risks from air pollution as well as to assess the potential health benefits of improving atmospheric $PM_{2.5}$ concentration. Even considering the intrinsic limitations and uncertainties of the analysis, it is an important information to rationalize the enforcement of $PM_{2.5}$ management policies and measures in Seoul, Korea.

• Journal of Korea Multimedia Society
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• v.10 no.7
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• pp.846-855
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• 2007

Significant feature extraction in cancer cell image analysis is an important process for grading cell carcinoma. In this study, we propose a method for 3D quantitative analysis of cell nuclei based upon digital image cytometry. First, we acquired volumetric renal cell carcinoma data for each grade using confocal laser scanning microscopy and segmented cell nuclei employing color features based upon a supervised teaming scheme. For 3D visualization, we used a contour-based method for surface rendering and a 3D texture mapping method for volume rendering. We then defined and extracted the 3D morphological features of cell nuclei. To evaluate what quantitative features of 3D analysis could contribute to diagnostic information, we analyzed the statistical significance of the extracted 3D features in each grade using an analysis of variance (ANOVA). Finally, we compared the 2D with the 3D features of cell nuclei and analyzed the correlations between them. We found statistically significant correlations between nuclear grade and 3D morphological features. The proposed method has potential for use as fundamental research in developing a new nuclear grading system for accurate diagnosis and prediction of prognosis.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.17 no.11
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• pp.214-222
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• 2016

As information becomes more sophisticated with the advancing technology of our times, the usability of software is considered an important factor. However, the research on usability of weapons system software graphical user interfaces (GUIs) remains insufficient. For this reason, this paper focuses on developing checklists for the usability of GUIs in weapons systems. In the first step, design principles are collected from various design guidelines on usability and from career soldiers. In the second step, a survey is conducted for factor analysis, and in the third step, factor analysis is conducted on 12 principles, with two principles excluded, as a result, due to less correlation with weapons system usability. In Step 4, the weights for design characteristics and design principles are derived using AHP. In the final step, the checklists are developed by mapping the GUI design factors and from the results of factor analysis. This research could be utilized as a foundation for usability evaluation of GUIs in weapons systems.

• The KIPS Transactions:PartA
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• v.16A no.3
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• pp.159-168
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• 2009

In this paper, we present an efficient way of implementing OpenGL ES 1.1 standard for the environments with hardware-supported OpenGL API, such as desktop PCs. Although OpenGL ES was started from the existing OpenGL features, it becomes a new three-dimensional graphics library customized for embedded systems through introducing fixed-point arithmetic operations, buffer management with fixed-point data type supports, completely new texture mapping functionalities and others. Currently, it is the official three dimensional graphics library for Google Android, Apple iPhone, PlayStation3, etc. In this paper, we achieved improvements on the arithmetic operations for the fixed-point number representation, which is the most characteristic data type for OpenGL ES. For the conversion of fixed-point data types to the floating-point number representations for the underlying OpenGL, we show the way of efficient conversion processes even with satisfying OpenGL ES standard requirements. We also introduced a simple memory management scheme to mange the converted data for the buffer containing fixed-point numbers. In the case of texture processing, the requirements in both standards are quite different and thus we used completely new software-implementations. Our final implementation result of OpenGL ES library provides all of over than 200 functions in OpenGL ES 1.1 standard and completely passed its conformance test, to show its compliance with the standard. From the efficiency viewpoint, we measured its execution times for several OpenGL ES-specific application programs and achieved at most 33.147 times improvements, to become the fastest one among the OpenGL ES implementations in the same category.