• Title/Summary/Keyword: Connectivity Index

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Habitat Connectivity Assessment of Tits Using a Statistical Modeling: Focused on Biotop Map of Seoul, South Korea (통계모형을 활용한 박새류의 서식지 연결성 평가: 서울시 도시생태현황도 자료를 중심으로)

  • Song, Wonkyong;Kim, Eunyoung;Lee, Dongkun
    • Journal of Environmental Impact Assessment
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    • v.22 no.3
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    • pp.219-230
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    • 2013
  • Species distribution modeling is one of the most effective habitat analysis methods for wildlife conservation. This study was for evaluating the suitability of species distribution to distance between forest patches in Seoul city using tits. We analyzed the distribution of the four species of tits: varied tit (Parus varius), marsh tit (P. palustris), great tit (P. major) and coal tit (P. ater), using the landscape indexes and connectivity indexes, and compared the resulting suitability indexes from 100m to 1,000m. As factors affecting to the distribution of tits, we calculated landscape indices by separating them into intra-patch indices (i.e. logged patch area (PA), area-weighted mean patch shape index (PSI), tree rate (TR)) and inter-patch indices (i.e. patch degree (PD), patch betweenness (PB), difference probability of connectivity (DPC)), to analyze the internal properties of the patches and their connectivity by tits occurrence data using logistic regression modeling. The models were evaluated by AICc (Akaike Information Criteria with a correction for finite sample sizes) and AUC (Area Under Curve of ROC). The results of AICc and AUC showed DPC, PA, PSI, and TR were important factors of the habitat models for great tit and marsh tit at the level of distance 500~800m. In contrast, habitat models for coal tit and varied tit, which are known as forest interior species, reflected PA, PSI, and TR as intra-patch indices rather than connectivity. These mean that coal tit and varied tit are more likely to find a large circular forest patch than a small and long-shaped forest patch, which are higher rate of forest. Therefore, different strategies are required in order to enhance the habitats of the forest birds, tits, in a region that has fragmented forest patches such as Seoul city. It is important to manage forest interior areas for coal tit and varied tit, which are known as forest interior species and to manage not only forest interior areas but also connectivity of the forest patches in the threshold distance for great tit and marsh tit as adapted species to the urban ecosystem for sustainable ecosystem management.

Analysis of Green Space Connectivity by Land Cover Changes: A Case Study of Yongin-si, South Korea

  • Woo Hyeon Park;Ye Inn Kim;Jin-Woo Park;Se Jin Oh;Seung Min Lim;Won Seok Jang
    • Journal of Forest and Environmental Science
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    • v.40 no.3
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    • pp.241-249
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    • 2024
  • Human development activities have led to changes in land cover, resulting in the loss of green spaces such as forests and agricultural lands. This loss accompanies issues of habitat reduction and hindrance to wildlife movement. Due to the decrease in urban green spaces, urban green connectivity is reducing. This study aims to analyze changes in green space connectivity through structural and functional changes in green spaces caused by land cover changes. Quantitative analysis of landscape patterns using landscape indices through Fragstats model was employed to analyze the structural changes in green spaces. This study used seven landscape indices to assess the fragmentation and isolation of green spaces. The analysis was focused on changes occurring in agricultural lands, forests, and grasslands within Yongin-si, South Korea, over 20 years from 1989 to 2019. Among the landscape indices for forests, PLAND showed a decrease of approximately 8.2% from 1989 to 2009, while NP exhibited a decline of about 2,025 patches. This indicates both a reduction in the total area of green spaces in Yongin-si. Also, we analyzed functional changes based on landscape index variations in forest land within the study area between 2009 and 2019, and least-cost path (LCP) analysis was conducted using Linkage Mapper. Results yielded 18 and 16 links for 2009 and 2019, respectively, with 12 common links. It was observed that five links showed a slight decrease, indicating partial deletions of links, contributing to the fragmentation and discontinuity of forests.

On the Mobile Client and Server Model (모바일 클라이언트-서버 모델에 관한 연구)

  • Lee, Jie-Young
    • The Journal of Information Technology
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    • v.12 no.1
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    • pp.15-20
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    • 2009
  • In this paper, we aim that it solve to problem of the database hoarding because a week connectivity of wireless networks and cutting of link, Consistency of shared data, optimizing of the log include to Mobile Continuous Query Processing System under the mobile client and server environment. and we demonstrate of the superiority for the new Mobile Continuous Query Processing System compare C-I-S(Client-Intercept -Server)model with performance. and we perform to various experiment in order to establishment of superiority compare the index architecture and method for the realtime Continuous Query Processing. in this paper.

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Interrelation of Retention Factor of Amino-Acids by QSPR and Linear Regression

  • Lee, Seung-Ki;Polyakova, Yulia;Row, Kyung-Ho
    • Bulletin of the Korean Chemical Society
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    • v.24 no.12
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    • pp.1757-1762
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    • 2003
  • The interrelation between retention factors of several L-amino acids and their physico-chemical and structural properties can be determined in chromatographic research. In this paper we describe a predictor for retention factors with various properties of the L-amino acids. Eighteen L-amino acids are included in this study, and retention factors are measured experimentally by RP-HPLC. Binding energy ($E_b$), hydrophobicity (log P), molecular refractivity (MR), polarizability (${\alpha}$), total energy ($E_t$), water solubility (log S), connectivity index (${\chi}$) of different orders and Wiener index (w) are theoretically calculated. Relationships between these properties and retention factors are established, and their predictive and interpretive ability are evaluated. The equation of the relationship between retention factors and various descriptors of L-amino acids is suggested as linear and multiple linear form, and the correlation coefficients estimated are relatively higher than 0.90.

Determination of Emergency Evacuation Roads Considering Road Network Function and Connectivity (도로네트워크 기능 및 연결성을 고려한 긴급대피교통로 선정)

  • Noh, Yunseung;Do, Myungsik
    • The Journal of The Korea Institute of Intelligent Transport Systems
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    • v.13 no.6
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    • pp.34-42
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    • 2014
  • This study is a fundamental research to determine the emergency evacuation roads considering road network function and connectivity. First of all, the functional aspects of the road networks are analyzed in the target area, Sejong city, by using degree centrality(DC) and closeness centrality(CC) from GIS based database. Secondly, how network connectivity makes a change in user's travel pattern and travel time and how it affects the whole network are analyzed using TransCAD simulation program. Finally, after performing cluster analysis of index, first and second emergency evacuation roads are determined by judging the characteristics of clusters. The results of this research will be helpful for making a decision to diminish secondary damages when confronting unexpected disasters.

Differences in Large-scale and Sliding-window-based Functional Networks of Reappraisal and Suppression

  • Jun, Suhnyoung;Lee, Seung-Koo;Han, Sanghoon
    • Science of Emotion and Sensibility
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    • v.21 no.3
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    • pp.83-102
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    • 2018
  • The process model of emotion regulation suggests that cognitive reappraisal and expressive suppression engage at different time points in the regulation process. Although multiple brain regions and networks have been identified for each strategy, no articles have explored changes in network characteristics or network connectivity over time. The present study examined (a) the whole-brain network and six other resting-state networks, (b) their modularity and global efficiency, which is an index of the efficiency of information exchange across the network, (c) the degree and betweenness centrality for 160 brain regions to identify the hub nodes with the most control over the entire network, and (d) the intra-network and inter-network functional connectivity (FC). Such investigations were performed using a traditional large-scale FC analysis and a relatively recent sliding window correlation analysis. The results showed that the right inferior orbitofrontal cortex was the hub region of the whole-brain network for both strategies. The present findings of temporally altering functional activity of the networks revealed that the default mode network (DMN) activated at the early stage of reappraisal, followed by the task-positive networks (cingulo-opercular network and fronto-parietal network), emotion-processing networks (the cerebellar network and DMN), and sensorimotor network (SMN) that activated at the early stage of suppression, followed by the greater recruitment of task-positive networks and their functional connection with the emotional response-related networks (SMN and occipital network). This is the first study that provides neuroimaging evidence supporting the process model of emotion regulation by revealing the temporally varying network efficiency and intra- and inter-network functional connections of reappraisal and suppression.

Analysis on the Korean Highway in 2011 and 2017 Using Algorithms of Accessibility indices (접근성 지표의 알고리즘을 이용한 2011년과 2017년의 우리나라 고속도로 분석)

  • Lee, Gwangyeon;Park, Kisoeb
    • Journal of the Korea Society for Simulation
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    • v.27 no.4
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    • pp.9-18
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    • 2018
  • This paper proposes new algorithms of accessibility indices to analyze the connectivity of the Korean highway network. First of all, we find a transportation network that presents Korea's highway network in graphs in 2011 and 2017. And we analyze and compare the nation's highway network in 2011 and 2017 using concepts such as associated number, the relative distance, the accessibility, the degree of connectivity, the index of dispersion, the diameter of graph theory. To do this, an algorithm is presented which can easily obtain various accessibility indices from a given transportation network. Using the simulation results of this study, we can find city that is the center of traffic in the highway transportation network. In addition, cities that are included in the network but are relatively underdeveloped can be found and used as basic data for enhancing the connectivity of the nationwide traffic in the future. Moreover, the proposed algorithms of accessibility indices, which are modeled on highway transport networks, can help identify the accessibility space structure of each city and provide criteria for efficient and reasonable selection of alternatives in various regional planning processes, including transportation.

An Analysis of Spatial Characteristics of Environmental-Friendly Certified Farms - Focused on Jeollanam-do - (친환경 인증 농경지의 공간적 특성 분석 - 전라남도를 대상으로 -)

  • Park, Yujin;Gu, Jeong-Yoon;Lee, Sang-Woo;An, Kyungjin;Choi, Jinah;Kim, Sangbum;Park, Se-Rin
    • Journal of Korean Society of Rural Planning
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    • v.29 no.3
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    • pp.79-89
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    • 2023
  • As the demand for environmental-friendly agricultural products continues to rise due to increased concerns regarding food safety and ecosystem conservation, it is becoming important to identify regions and spatial locations where environmental-friendly should be intensively established for production integration. This study aims to analyze the spatial distribution of environmental-friendly certified farms in Jeollanam-do, South Korea. Spatial statistical analysis based on Local Moran's I and Getis-Ord Gi* were used to identify spatial cluster characteristics and landscape indices were utilized to analyze spatial patterns of environmental-friendly certified farms. The results indicated that Haenam-gun, Gangjin-gun, Muan-gun, and Jindo-gun were identified as hotspots, while Muan-gun, Goheung-gun, and Jindo-gun exhibited high connectivity. This suggests that environmental-friendly certified farms in Muan-gun and Jindo-gun were clustered and closely connected to one another. Based on the results of the spatial distribution of environmental-friendly certified farms, areas belonging to the hotspot and with high connectivity should be managed as clustered districts to secure the foundation and system of environmental-friendly certified farms. Areas that belong to cold spots and have low connectivity should be preceded by measures to promote conversion to environmental-friendly agriculture. In addition, it is necessary to make it possible to create a large-scale cluster district through a long-term spatial planning strategy to expand the environmental-friendly certified farms. The findings of this study can provide quantitative data on policies and discussions for developing a model for rural spatial planning.

The Analysis of Landscape Ecological Characteristics in Rural Residential Area (농촌 정주공간의 경관생태학적 특성 분석 - 내태1리와 검단1리의 사례지를 중심으로 -)

  • Ra, Jung-Hwa;Cha, Sung Yun;Do, Hu-Jo;Lee, Jung Min
    • Journal of the Korean Society of Environmental Restoration Technology
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    • v.8 no.2
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    • pp.1-20
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    • 2005
  • The purpose of this paper is to classify two study sites into the biotope types and investigate the landscape ecological characteristics of them. This will be available for the rural planning in the aspect of environmental preservation. The summaries of the result are as follows. 1) In the result of the area assessment in biotope groups, a dry field (32%) and a paddy field (28%) are more than 50%, but settlement space and water space are less than 10%. The result shows the land use condition of rural areas. 2) In the investigation result of elongation, running water spaces are higher than other biotope groups relatively, it is because they long shaped and 1-3m narrow. 3) In case of Fractal index analysis, residential spaces and cultivated lands are investigated to be lower in numerical value, it is because they have the definite borders and get simple in the border of landscape by human intervention. 4) In case of dispersion degree, the dry field has the highest value because they are located close by forests spread widely around study sites. It means that the land which is used by artificial purpose get more value rather than natural lands 5) In the connectivity analysis, a paddy field and a residential space appear the highest. It is because residence spaces spread intensively through roads and a paddy field, through streams. 6) In rural landscape, the diversity of landscape is investigated to be simple. A paddy field and a dry field contain small sized patches that have been divided by human intervention. Besides, there appear much different vegetation around waterways and farm-roads.

A Blind Watermarking for 3-D Mesh Sequence Using Temporal Wavelet Transform of Vertex Norms (꼭지점 좌표 벡터 크기값의 시간축 웨이블릿 변환을 이용한 3차원 메쉬 시퀀스의 블라인드 워터마킹)

  • Kim, Min-Su;Cho, Jae-Won;Prost, Remy;Jung, Ho-Youl
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.32 no.3C
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    • pp.256-268
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    • 2007
  • In this paper, we present a watermarking method for 3-D mesh sequences. The main idea is to transform vertex norm with the identical connectivity index along temporal axis using wavelet transform and modify the distribution of wavelet coefficients in temporally high (or middle) frequency frames according to watermark bit to be embedded. All vertices are divided into groups, namely bin, using the distribution of coefficients in low frequency frames. As the vertices with the identical connectivity index over whole frames belong to one bin, their wavelet coefficients are also assigned into the same bin. Then, the watermark is embedded into the wavelet coefficients of vertex norm. Due to the use of the distribution, our method can retrieve the hidden watermark without any information about original mesh sequences in the process of watermark detection. Through simulations, we show that the proposed is flirty robust against various attacks that are probably concerned in copyright protection of 3-D mesh sequences.