• Title/Summary/Keyword: Level Set Method

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A Study on the Selection of Evaluation Index of Biotopes in Korea (한국 비오톱 평가지표의 선정 실태)

  • Kim, Young-Sun;Oh, Koo-Kyoon
    • Journal of the Korean Institute of Landscape Architecture
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    • v.41 no.2
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    • pp.27-37
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    • 2013
  • The purpose of this research is to identify the selection status of the evaluation index in Korea and suggest improvements. In order to do so, comparison and analysis are conducted of terms, items and measures for biotope evaluation indexes attested in related documents published in domestic and foreign areas. The findings of this research are listed in the following. First, terms about biotope evaluation indexes are used and integrated with each other. Second, items used to denote biotope evaluation indexes are largely different in each region since comprehensive concepts have not been established for selecting the items. Third, there are poor grounds for items denoting biotope evaluation indexes to the species of creatures. Fourth, the items cannot provide satisfying explanations for the relative values of the current condition in the urban ecosystem of a specific region. The results of this research may be applied to provide basic materials about what is to be improved for selecting biotope evaluation indexes in Korea. In order to systematically preserve an urban ecosystem environment in Korea for the future, it is necessary for the state to develop and set up such evaluation indexes and guidelines that reflect the relative values of biotopes in each level of urban areas in Korea.

On the Study of Initializing Extended Depth of Focus Algorithm Parameters (Extended Depth of Focus 알고리듬 파라메타 초기설정에 관한 연구)

  • Yoo, Kyung-Moo;Joo, Hyo-Nam;Kim, Joon-Seek;Park, Duck-Chun;Choi, In-Ho
    • Journal of Broadcast Engineering
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    • v.17 no.4
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    • pp.625-633
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    • 2012
  • Extended Depth of Focus (EDF) algorithms for extracting three-dimensional (3D) information from a set of optical image slices are studied by many researches recently. Due to the limited depth of focus of the microscope, only a small portion of the image slices are in focus. Most of the EDF algorithms try to find the in-focus area to generate a single focused image and a 3D depth image. Inherent to most image processing algorithms, the EDF algorithms need parameters to be properly initialized to perform successfully. In this paper, we select three popular transform-based EDF algorithms which are each based on pyramid, wavelet transform, and complex wavelet transform, and study the performance of the algorithms according to the initialization of its parameters. The parameters we considered consist of the number of levels used in the transform, the selection of the lowest level image, the window size used in high frequency filter, the noise reduction method, etc. Through extended simulation, we find a good relationship between the initialization of the parameters and the properties of both the texture and 3D ground truth images. Typically, we find that a proper initialization of the parameters improve the algorithm performance 3dB ~ 19dB over a default initialization in recovering the 3D information.

Comparison of physics-based and data-driven models for streamflow simulation of the Mekong river (메콩강 유출모의를 위한 물리적 및 데이터 기반 모형의 비교·분석)

  • Lee, Giha;Jung, Sungho;Lee, Daeeop
    • Journal of Korea Water Resources Association
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    • v.51 no.6
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    • pp.503-514
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    • 2018
  • In recent, the hydrological regime of the Mekong river is changing drastically due to climate change and haphazard watershed development including dam construction. Information of hydrologic feature like streamflow of the Mekong river are required for water disaster prevention and sustainable water resources development in the river sharing countries. In this study, runoff simulations at the Kratie station of the lower Mekong river are performed using SWAT (Soil and Water Assessment Tool), a physics-based hydrologic model, and LSTM (Long Short-Term Memory), a data-driven deep learning algorithm. The SWAT model was set up based on globally-available database (topography: HydroSHED, landuse: GLCF-MODIS, soil: FAO-Soil map, rainfall: APHRODITE, etc) and then simulated daily discharge from 2003 to 2007. The LSTM was built using deep learning open-source library TensorFlow and the deep-layer neural networks of the LSTM were trained based merely on daily water level data of 10 upper stations of the Kratie during two periods: 2000~2002 and 2008~2014. Then, LSTM simulated daily discharge for 2003~2007 as in SWAT model. The simulation results show that Nash-Sutcliffe Efficiency (NSE) of each model were calculated at 0.9(SWAT) and 0.99(LSTM), respectively. In order to simply simulate hydrological time series of ungauged large watersheds, data-driven model like the LSTM method is more applicable than the physics-based hydrological model having complexity due to various database pressure because it is able to memorize the preceding time series sequences and reflect them to prediction.

A Biomechanical Analysis of Four Different Taekwondo Body Punch Types in Horseback-Riding Stance (태권도 주춤 서 몸통지르기 유형별 생체역학적 변인 비교 분석)

  • Kang, Sung-Chul;Kim, Eui-Hwan;Shin, Hyun-Moo;Kim, Sung-Sup;Kim, Tae-Whan
    • Korean Journal of Applied Biomechanics
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    • v.17 no.4
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    • pp.201-208
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    • 2007
  • The purpose of this study is to compare 4 different body punch types(type 1: a punch using a shoulder, type 2: a punch using a waist, type 3: a punch using lower extremities, and type 4: a punch with elbows by your side at chest level) in horseback-riding stance and establish suitable teaching theory and method, which would be a useful reference to Taekwondo instructors on the spot(in Taekwondo dojangs all around Korea). Five exhibition players from Korean national Taekwondo exhibition team participated in this study. Each participant was asked to perform the four different types of punches and their kinematic and kinetic data were recorded with 7 vicon cameras(125Hz) and two force plates(AMTI, 1200Hz). We analyzed displacement, time, resultant center of body mass trajectory, velocity, trunk angular velocity, and ground reaction force(GRF) from each body segment in body punch and the result. I performed 1-way ANOVA(RM) for average values of each player after standardization and statistical significance was set as p<.05. was as the following ; First, they showed a tendency to take the body punch posture with the biggest motion at a shoulder and on descending order a waist and a knee. Second, a mean time for each body punch on ascending order 0.46sec. for type 2, 0.49sec for type 3, 0.50sec. for type 4, and 0.56sec. for type 1. Third, a mean resultant center of body mass trajectory for each body punch the longest 4.07cm for type 3 and the shortest 2.458cm for type 1. Fourth, a mean of maximal velocity of a fist strike was the fastest 5.99m/s for type 3, 5.93m/s for type 4, 5.67m/s for type 2, and 5.01m/s for type 1 on the descending order. Fifth, a mean of maximal trunk angular velocity of the fastest 495.6deg./sec. for type 4 and 337.7deg./sec. for type 1 on the descending order. Sixth, strongest value was type 3, 2 for anterior-posterior ground reaction force(left -54.89N, right 60.58N), type 4 for medial-lateral GRF(left 83.59N, right -80.12N), and type 3 for vertical GRF(left 341.79N, right 426.11N).

Simultaneous Analysis and Anti-allergic Effect of Mume Fructus (오매(烏梅)의 다성분 동시분석 및 항알러지 효과)

  • Seo, Chang-Seob;Ha, Hyekyung;Lee, Ho Young;Lee, JunKyung;Jung, Dayoung;Lee, Jin-Ah;Shin, Hyeun Kyoo
    • Korean Journal of Pharmacognosy
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    • v.43 no.4
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    • pp.279-285
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    • 2012
  • The Mume Fructus (MF) has been used for relieves cough, arrests arrest chronic diarrhea, treat fluid depletion, and treat ascariasis in Korea. In this study, a high-performance liquid chromatography (HPLC) method was established for simultaneous determination of six main components of MF. Additionally, we were investigated the anti-inflammatory and anti-allergic effects of MF extract on lipopolysaccharide (LPS)-treated RAW264.7 cells and tumor necrosis factor (TNF)-${\alpha}$/interferon (IFN)-${\gamma}$-treated HaCaT cells. The analytical column for separation was used a Gemini $C_{18}$ column maintained at $40^{\circ}C$. The mobile phase consisted of 1.0% (v/v) acetic acid in water (A) and 1.0% (v/v) acetic acid in acetonitrile (B). The flow rate was 1.0 mL/min and the detector was a photodiode array (PDA) set at 280 nm and 320 nm. We evaluated the inhibitory effect of MF extract on the production of inflammatory markers, nitric oxide (NO) and prostaglandin $E_2$ ($PGE_2$) in LPS-stimulated RAW264.7 cells and thymus- and activation-regulated chemokine (TARC/CCL17) in TNF-${\alpha}$/IFN-${\gamma}$-treated HaCaT cells, respectively. We confirmed the genes expression related with TARC, macrophage-derived chemokine (MDC/CCL22) and regulated on activation, normal T cell expressed and secreted (RANTES/CCL5) in HaCaT keratinocyte cells by MF extract. The contents of the five compounds in MF were 0.22-1.01 mg/g. Also, the MF extract show inhibition of about 78% and 75% on NO and $PGE_2$ production at the concentration 1000 mg/mL in RAW264.7 cells. MF extract suppressed the hTARC level and genes expression such as TARC, MDC, and RANTES on TNF-${\alpha}$/IFN-${\gamma}$-treated HaCaT cells.

Screening of genes differentially expressed in cultured human periodontal ligament cells and human gingival fibroblasts (배양된 치주인대세포와 치은섬유아세포에서 상이하게 발현된 유전자들의 검토 양상)

  • Yoon, Hye-Jeong;Choi, Mi-Hye;Yeo, Shin-II;Park, Jin-Woo;Choi, Byung-Ju;Kim, Moon-Kyu;Kim, Jung-Chul;Suh, Jo-Young
    • Journal of Periodontal and Implant Science
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    • v.36 no.3
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    • pp.613-625
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    • 2006
  • Periodontal ligament(PDL) cells and human gingival fibroblasts(HGFs) play important roles in development, regeneration, normal function, and pathologic alteration. PDL cells and HGFs have the similarity related with general characteristics of fibroblast such as spindle shaped morphology, the presence of vimentin intermediate filament and the synthesis of interstitial collagens and fibronectin. There were many studies about the differences between PDL cells and HGFs, but they were not about whole gene level. In this study, we tried to explain the differences of gene expression profiles between PDL cells and HGFs, and the differences among three individuals by screening gene expression patterns of PDL cells and HGFs, using cDNA microarray. Although there were some variants among three experiments, a set of genes were consistentely and differentially expressed in one cell type. Among 3,063 genes, 49 genes were more highly expressed in PDL cells and 12 genes were more highly expressed in HGFs. The genes related with cell structure and motility were expressed more highly in PDL cells. These are cofilin 1, proteoglycan 1 secretory granule, collagen type I(${\alpha}$ 1), adducin gamma subunit, collagen type III(${\alpha}$ 1), fibronectin, lumican(keratan sulfate proteoglycan), and ${\alpha}$ -smooth muscle actin. Tissue inhibitor of metalloproteinase known as the enzyme controlling extracellular matrix with matrix metalloproteinase is more highly expressed in PDL cells, osteoprotegerin known as osteoclastogenesis inhibitory factor is more highly expressed in HGFs. We performed northern blot to verify cDNA microarray results on selected genes such as tissue inhibitor of metalloproteinase, fibronectin, osteoprogeterin. The result of northern blot analysis showed that each cell expressed the genes in similar pattern with cDNA microarray result. This result indicates that cDNA microarray is a reliable method in screening of gene expression profiles.

Shipboard Active Phased Array Antenna System for Satellite Communications (위성 통신용 선박 탑재 능동 위상배열 안테나 시스템)

  • 전순익;채종석;오승엽
    • The Journal of Korean Institute of Electromagnetic Engineering and Science
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    • v.13 no.10
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    • pp.1089-1097
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    • 2002
  • In this paper, the novel shipboard Active Phased Array Antenna(APAA) system for maritime mobile satellite communications is introduced. The antenna uses novel technologies like wide range hybrid tracking, single antenna elements with both of Rx and Tx, asymmetrical array structure, interference isolation between Rx and Tx, and error correction method from frequency scan effect. The antenna has single aperture for both of Rx and Tx with 32 $\times$ 4 two-dimensional array. The antenna has two beams. Its frequencies are 7.25 ~ 7.75 GHz for Rx and 7.9 ~ 8.4 GHz for Tx. The antenna gains are 35.4 dBi for Rx and 35.7 dBi for Tx, those are 54 % of efficiency. The electrically steering ranges are $\pm$35$^{\circ}$ of elevation direction and $\pm$4$^{\circ}$ of azimuth direction. The mechanical control ranges at hybrid tracking capability are continuous 360$^{\circ}$ of azimuth direction and $\pm$10$^{\circ}$ of elevation direction. The antenna has 2.2$^{\circ}$ of 3 dB beamwidth, -14 dB of sidelobe level, and 21 dB of cross-pol suppression. The antenna performance was measured by near field measurement set. Its system performance was tested on the ship motion simulator and with the satellite transponder simulator. The test result showed that its tracking error was within -3 dB from its peak gain under motion condition. The antenna system was tested by real modulated Direct Broadcasting Satellite(DBS) signals to check its communication processing function.

Analysis of Volatile Components of a Chicken Model Food System in Retortable Pouches Using Multivariate Method (다변량 해석을 이용한 레토르트 파우치 계육 모형식품의 휘발성분 분석)

  • Choi, Jun-Bong;Kim, Jung-Hwan;Moon, Tae-Wha
    • Korean Journal of Food Science and Technology
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    • v.28 no.6
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    • pp.1171-1176
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    • 1996
  • The changes in volatiles of the model system were analyzed by GC and GC-MS before and after retorting. The GC data were analyzed statistically by applying the analysis of variance, and 42 peaks were selected at 5% significance level. Multivariate statistical analysis was performed with these 42 peaks as independent variables. Through the stepwise discriminant analysis, 8 peaks, which corresponded to the compounds such as 2-heptanone, cis-3-hexenal, 2-pentyl-furan, 1-methyl-trans-1,2-cyclohexanediol, 2-hexanone, 3-octanone, trans, trans-nona-2,4-dienal and 1-octen-3-ol, were obtained in sequence to distinguish the samples with and without retorting. The principal component analysis of a set of 8 independent variables resulted in 3 principal components which accounted for 96.1% of the variance, while the first principal component (PC 1) explained 76.5% of the total variance. In addition, through the factor analysis of the principal components, the peaks 11, 20 and 21 could be grouped togather in accordance with the direction and the size while the peaks 9, 33 and 39 constituted the second group in the direction.

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A Study on Mapping 3-D River Boundary Using the Spatial Information Datasets (공간정보를 이용한 3차원 하천 경계선 매핑에 관한 연구)

  • Choung, Yun-Jae;Park, Hyen-Cheol;Jo, Myung-Hee
    • Journal of the Korean Association of Geographic Information Studies
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    • v.15 no.1
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    • pp.87-98
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    • 2012
  • A river boundary is defined as the intersection between a main stream of a river and the land. Mapping of the river boundary is important for the protection of the properties in river areas, the prevention of flooding and the monitoring of the topographic changes in river areas. However, the utilization of the ground surveying technologies is not efficient for the mapping of the river boundary due to the irregular surfaces of river zones and the dynamic changes of water level of a river stream. Recently, the spatial information data sets such as the airborne LiDAR and aerial images are widely used for coastal mapping due to the acquisition of the topographic information without human accessibility. Due to these advantages, this research proposes a semi-automatic method for mapping of the river boundary using the spatial information data set such as the airborne LiDAR and the aerial photographs. Multiple image processing technologies such as the image segmentation algorithm and the edge detection algorithm are applied for the generation of the 3D river boundary using the aerial photographs and airborne topographic LiDAR data. Check points determined by the experienced expert are used for the measurement of the horizontal and vertical accuracy of the generated 3D river boundary. Statistical results show that the generated river boundary has a high accuracy in horizontal and vertical direction.

Case study of organization and operation expansion in General high school technology course (일반 고등학교 기술과 교육과정 편성·운영 사례 연구)

  • Lim, Yun-Jin
    • 대한공업교육학회지
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    • v.43 no.2
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    • pp.97-113
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    • 2018
  • The purpose of this study was to investigate the process and meaning of the expansion of the technology education curriculum of general high school. For the study, research problems were set up according to the procedure of case study method, and cases suitable for research were identified and data were collected through interviews with the teachers of the schools. The examples used in the study were two high schools in Gyeonggi - do, and the collected data were visualized in concept form through semantic analysis process. The results of the two schools are summarized as follows. First, the revision of unit school curriculum has been started through crisis and challenge awareness. Second, it is necessary to use the free lecture system suggested in the 2015 revised curriculum. Third, students should change their perceptions of students and curriculum by enhancing class through various skills and education activities suitable for high school level. Fourth, we must continuously strive to develop professionalism as a technology teacher. It is difficult to expand the curriculum of the school because there is only one technology teacher in the general high school. However, through the cases of this study, it is expected that the importance of the technology subject and the change of awareness will be realized as various education activities for the career choice in the high school credit system. do.