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An Application of the Multi-slope MUSCL to the Shallow Water Equations (천수방정식에 대한 다중 경사 MUSCL의 적용)

  • Hwang, Seung-Yong;Lee, Sam-Hee
    • Journal of Korea Water Resources Association
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    • v.44 no.10
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    • pp.819-830
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    • 2011
  • The multi-slope MUSCL, proposed by T. Buffard and S. Clain, determines slopes of conserved variables at each edge of a cell in the linear reconstructions of data. In this study, the second order accurate numerical model was developed according to the multi-slope MUSCL to solve the shallow water equations on the unstructured grids. The HLLL scheme of approximate Riemann solvers was used to calculate fluxes. For the review of the applicability of the developed model, the results of the model were compared to the 'isolated building test' and the 'model city flooding experiment' conducted as part of the IMPACT (Investigation of extreMe flood Processes And unCerTainty) project in Europe. There were limitations to predict abrupt rising of water depths by the resistance of model buildings and water depths at the specific locations among the buildings. But they were identified as the same problems also revealed in results of the other models to the same experiment. On the more refined meshes to the 'model city flooding experiment' simulated results showed good agreement with measurements. It was verified that the developed model simulated well the complex phenomena such as a dam-break problem and the urban inundation by flash floods.

A Grouping Method of Photographic Advertisement Information Based on the Efficient Combination of Features (특징의 효과적 병합에 의한 광고영상정보의 분류 기법)

  • Jeong, Jae-Kyong;Jeon, Byeung-Woo
    • Journal of the Institute of Electronics Engineers of Korea CI
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    • v.48 no.2
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    • pp.66-77
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    • 2011
  • We propose a framework for grouping photographic advertising images that employs a hierarchical indexing scheme based on efficient feature combinations. The study provides one specific application of effective tools for monitoring photographic advertising information through online and offline channels. Specifically, it develops a preprocessor for advertising image information tracking. We consider both global features that contain general information on the overall image and local features that are based on local image characteristics. The developed local features are invariant under image rotation and scale, the addition of noise, and change in illumination. Thus, they successfully achieve reliable matching between different views of a scene across affine transformations and exhibit high accuracy in the search for matched pairs of identical images. The method works with global features in advance to organize coarse clusters that consist of several image groups among the image data and then executes fine matching with local features within each cluster to construct elaborate clusters that are separated by identical image groups. In order to decrease the computational time, we apply a conventional clustering method to group images together that are similar in their global characteristics in order to overcome the drawback of excessive time for fine matching time by using local features between identical images.

Characterization of a Cold Tolerance-related Gene, BrCSR, Derived from Brassica rapa (배추 유래 저온 저항성 관련 유전자, BrCSR의 특성 분석)

  • Yu, Jae-Gyeong;Park, Young-Doo
    • Horticultural Science & Technology
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    • v.32 no.1
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    • pp.91-99
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    • 2014
  • The objective of this study is to identify cold-tolerance genes in Brassica rapa. In order to acheive this goal, we analyzed a KBGP-24K oligo chip data [BrEMD (B. rapa EST and Microarray Database)] using B. rapa ssp. pekinensis inbred line 'Chiifu' under cold stress condition ($4^{\circ}C$). Among 23,929 unigenes of B. rapa, 417 genes (1.7%) were primarily identified as cold responsive genes that were expressed over 5-fold higher than those of wild type control, and then a gene which has unknown function and has full length sequence was selected. It was named BrCSR (B. rapa Cold Stress Resistance). BrCSR was transformed using expression vector pSL101 to confirm whether BrCSR can enhance cold tolerance in tobacco plants. $T_1$ transgenic tobacco plants expressing BrCSR were selected by PCR and Southern hybridization analyses, and the function of BrCSR was characterized by expression level analysis and phenotype observation under cold stress condition. The expression level of BrCSR in transgenic tobacco plants increased up to about two folds in quantitative real-time RT-PCR assay and this was very similar to Northern blot hybridization analysis. Analysis of phenotypic characteristics clearly elucidated that transgenic tobaccos expressing BrCSR were more cold tolerant than wild type control under $4^{\circ}C$ treatment. Based on these results, we conclude that the over-expression of BrCSR might be closely related to the enhancement of cold tolerance.

Comparative Modeling of Human Tyrosinase - an Important Target for Developing Skin Whitening Agents (피부 미백제의 타겟 단백질인 인간 티로시나제의 3차원 구조 상동 모델링)

  • Choi, Jongkeun;Suh, Joo Won
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.13 no.11
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    • pp.5350-5355
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    • 2012
  • Human tyrosinase (hTyr) catalyzes the first and rate limiting step in the biosynthesis of a skin color determinant, melanin. Although a number of cosmetic companies have tried to develop hTyr inhibitors for several decades, absence of 3D structure of hTyr make it impossible to design or screen inhibitors by structure-based approach. Therefore, we built a 3D structure by comparative modeling technique based on the crystal structure of tyrosinase from Bacillus megaterium to provide structural information and to search new hit compounds from database. Our model revealed that two copper atoms of active site located deep inside and were coordinated with six strictly conserved histidine residues coming from four-helix-bundle. Substrate binding site had narrow funnel like shape and its entrance was wide and exposed to solvent. In addition, hTyr-tyrosine and hTyr-kojic acid, a well-known inhibitor, complexes were modeled with the guide of solvent accessible surface generated by in-house software. Our model demonstrated that only phenol group or its analogs could fill the binding site near the nuclear copper center, because inside of binding site had narrow shape relatively. In conclusion, the results of this study may provide helpful information for designing and screening new anti-melanogenic agents.

Study on Converged English-Science Teaching Methods Using the PBL Model in Elementary Schools (PBL 모형을 적용한 초등학교 영어·과학 융합 수업)

  • Park, In-Hwa
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.21 no.6
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    • pp.78-83
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    • 2020
  • The information and knowledge of modern society in the 2lst century is changing rapidly. Based on this social change, the ministry of education introduced STEAM (Science Technology Engineering Art Music) in 2011 to foster creative convergence talents. Therefore, this study is based on the PBL model that learners participate in the class voluntarily to develop appropriate talents in the 21st century. The combined subjects were English, which is the world's official language, and Science, which is found in almost all the fields with the development of the 4th industrial revolution. As a result, learners could define the problems and solutions during the English class and take part in the group activity actively to obtain the problems and solutions of environmental pollution during the Science class. Through this, learners answered that they had a great understanding of learning (86%), high motivation for learning (100%), improved self-confidence (100%), and improved collaboration and creativity (100%). Unfortunately, this study does not progress actively due to the entrance exams, which still require accurate answers rather than the necessity and effectiveness of convergence education. To foster talents suitable for the present age, more active research should be applied to a range of educational sites.

Sexual Behavior and Sex Pheromone Gland of the Apple Leafminer, Phyllonorycter ringoniella(Lepidoptera: Gracillariidae) (사과굴나방(Phyllonorycter ringoniella)의 생식행동과 성페로몬샘 구조)

  • 정창훈;부경생
    • Korean journal of applied entomology
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    • v.36 no.4
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    • pp.323-330
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    • 1997
  • The apple leafminer, Phyllonorycrer ringoniella (Lepidoptera: Gracillariidae), is the most important pest on apple leaves and is not easy to be controlled with insecticides because of leafmining habit of its larvae. This study was undertaken to develop an artificial diet for mass rearing of the moth, and to look at their reproductive behavior. For developing an artificial diet the problem of diet contamination with microorganisms and how to supply artificial diet to first instar larvae have to be solved first. Artificial oviposition trial was successful with shadowy bottomside of various papers sprayed with apple leaf extracts. The highest activity of both calling and mating was observed within 30 min. after the onset of photophase and 3- to 4-day -old adults showed the highest mating rate. A ring-shaped sex pheromone gland was found at the intersegmental membrane between the 8th and 9th abdominal segments of the female. (E, 2)-4,lOtetradecadienyl acetate was identified as the major component from the femall gland extracts by the gas chromatography (GC) and GC-mass spectrometry. Additionally it was thought that (a-10-tetradecenyl acetate could be the second component of their sex pheromone.

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A Method of Hand Recognition for Virtual Hand Control of Virtual Reality Game Environment (가상 현실 게임 환경에서의 가상 손 제어를 위한 사용자 손 인식 방법)

  • Kim, Boo-Nyon;Kim, Jong-Ho;Kim, Tae-Young
    • Journal of Korea Game Society
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    • v.10 no.2
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    • pp.49-56
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    • 2010
  • In this paper, we propose a control method of virtual hand by the recognition of a user's hand in the virtual reality game environment. We display virtual hand on the game screen after getting the information of the user's hand movement and the direction thru input images by camera. We can utilize the movement of a user's hand as an input interface for virtual hand to select and move the object. As a hand recognition method based on the vision technology, the proposed method transforms input image from RGB color space to HSV color space, then segments the hand area using double threshold of H, S value and connected component analysis. Next, The center of gravity of the hand area can be calculated by 0 and 1 moment implementation of the segmented area. Since the center of gravity is positioned onto the center of the hand, the further apart pixels from the center of the gravity among the pixels in the segmented image can be recognized as fingertips. Finally, the axis of the hand is obtained as the vector of the center of gravity and the fingertips. In order to increase recognition stability and performance the method using a history buffer and a bounding box is also shown. The experiments on various input images show that our hand recognition method provides high level of accuracy and relatively fast stable results.

Chemical Weathering Index of Clastic Sedimentary Rocks in Korea (국내 쇄설성 퇴적암의 화학적 풍화지수 고찰)

  • Kim, Sung-Wook;Choi, Eun-Kyoung;Kim, Jong-Woo;Kim, Tae-Hyung;Lee, Kyu-Hwan
    • The Journal of Engineering Geology
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    • v.27 no.1
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    • pp.67-79
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    • 2017
  • Evaluation of the weathering index using the quantitative element composition of rocks is very effective in predicting the degree of weathering of rocks and the secondary weathering residuals. While the process of weathering varies according to the types of rocks, the study of weathering in Korea is concentrated on acidic igneous rocks. This study calculated the weathering indices using whole rock analysis (X-ray fluorescence analysis) of sandstone, mudstone, and shale belonging to clastic sedimentary rocks. The statistical significance of the indices was examined based on the correlation of the calculated weathering indices. Clastic sedimentary rocks showed higher significance of Wp, CIA, CIW and PIA weathering index indicating weathering of feldspar. Chemical Index of alteration (CIA) has the advantage of predicting weathering pathway and clay mineral production, but it is effective to consider chemical index of weathering index (CIW) simultaneously to improve accuracy. In order to reduce uncertainties due to carbonate rocks and to estimate the accurate weathering index, rock samples with high CaO content should be excluded from the evaluation of weathering index.

Mortality Forecasting for Population Projection (장래인구추계를 위한 사망률 예측)

  • Kim, Tai-Hun
    • Korea journal of population studies
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    • v.29 no.2
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    • pp.27-51
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    • 2006
  • In this paper, I have tested various kinds of methods for mortality projection and chose Lee-Carter method for projection of Korean mortality by age and sex. I reviewed the trends of life tables and life expectancies by age and sex from 2005 to 2050 projected by Lee-Carter method and found that the method was very applicable for Korean mortality projection. The differences between reported and estimated data for the period of 1971-2003 were small enough for both sexes and for all of the age groups. The projected life expectancies in 2051 were 82.73 years for males and 89.41 for females, and the differences decreased from 7.06 years in 2005 to 6.68 years. Because of the limitation of Korean infant mortality rate, I adopted the Japanese estimated IMR in 2050 as Korean object level in 2051. When the time series of IMR become long enough, we can use Korean IMR directly for the mortality projection. In addition, if we can estimate the changes of the main cause of death correctly in future, the mortality projection will be more correct and reliable. This will be available when we can produce a long series of life tables by cause of deaths.

The relationships among perception of physique, self-esteem, sociality, and behavioral characteristics in children (소아의 체격에 대한 인식, 자아존중감, 사회성 및 행동특성간의 관계)

  • Jung, Min-Ja;Yoon, Kyung-Lim;Shim, Kye-Shik
    • Clinical and Experimental Pediatrics
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    • v.51 no.10
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    • pp.1052-1057
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    • 2008
  • Purpose : This study was to examine the relations of perception of physique with self-esteem, sociality and problematic behaviors in children. Methods: Four hundred sixty five (231 boys and 234 girls) children were divided into three groups according to their height or body mass index according to the physical growth standard table had been presented in 2007 by the Korean Pediatric Society. The group 1, 2, and 3 was short, borderline and normal or obese, overweight and normal, respectively. Their perception and satisfaction of height and weight were investigated, and their self esteem and behavior styles were examined with Self-Esteem Inventory (SEI) and Korean Child Behavior Checklist (K-CBCL). We compared the numbers of appropriate perception, satisfaction, self-esteem and problematic behaviors in each group, and analyzed the relationship among perception of physique, self-esteem, sociality, and behavioral characteristics. The collected data were analyzed with chi-square test, ANOVA and Pearson correlation coefficient used with SPSS (ver. 12.0). Results : There were significant mismatches among their real physique perception and satisfaction (P<0.05). There were no significant differences of their self-esteem, sociality, and problematic behaviors according to their actual height and weight. There were significant differences of their self-esteem according to their perception or satisfaction of their height and weight (P<0.01). Conclusion : The children who considered themselves have short stature or obesity had problematic behaviors or low self-esteem. Therefore, children should be educated to have the appropriate perception of their own body image.