• Ecology and Resilient Infrastructure
• /
• v.9 no.2
• /
• pp.93-99
• /
• 2022

It was confirmed that the fish diversity decreased with increasing index of weir's density (IWD) in the four river systems. The IWD showed difference with watershed, it was high in the Nakdong River (NDR). Both two river systems of Gum River (GUR) and Yeongsan River (YSR) were similar, whereas relatively lower density observed in the Han River (HNR) system. A result of 2-Dimensional Kolmogorov-Smirnov (2-DKS) as a nonparametic test showed different threshold values affecting fish diversity with the river systems. The p-values based on D_max, were significantly different at 0.05 level (except for YSR). The threshold values affecting fish diversity were also different with watershed. The values were 1.6/km of the HNR, 1.3/km of the NDR, and 2.3/km of the GUR, respectively. The fish diversity was decreased when IWD is over threshold values. The IWD of total 404 rivers (about 33%) among 1,217 surveyed in this study showed above threshold value. These rivers should be considered first for evaluating river continuity. The IWD and threshold value suggested in this study would be useful for selecting a stream priority for river connectivity study.

• Land and Housing Review
• /
• v.15 no.1
• /
• pp.77-97
• /
• 2024

This study aims to examine the distinctions in evaluation index items between overseas and domestic ecological area-related systems, derive analytical indicators, and assess recently completed apartment complexes before and after the implementation of overall ecological area ratios. The objective is to analyse variances in the application of ecological area characteristics, categorizing them into ecological area analysis indicators and presenting their implications. The spatial scope covers completed apartment complexes in both metropolitan and non-metropolitan areas. Thirty-six completed apartment complexes were selected for analysis, and basic ecological area data were compiled. Subsequently, the data was utilized to categorize three analysis indicators-ecological area ratio, ecological area diversity, and ecological area connectivity-by metropolitan and non-metropolitan areas, as well as by type of apartment complex (sale housing versus rental housing) and size (large-scale, medium-scale, and small-scale). Results of the analysis indicate higher ecological area ratios and greater diversity in ecological area spatial types in metropolitan areas compared to non-metropolitan areas, and in pre-sale housing complexes compared to rental housing complexes. Mediumand large-scale apartment complexes exhibit higher ecological area ratios, with ecological area diversity being more pronounced. Ecological area connectivity reveals more numerous and varied connection points and types in metropolitan areas than in non-metropolitan areas. Implications of this study suggest that large-scale development should prioritize securing ecological area ratios and diversity in apartment complexes. Enhancing biodiversity necessitates establishing connections within and beyond the ecological area network of the complex. Future research should focus on linking the ecological area network within the complex.

• Korean Journal of Biological Psychiatry
• /
• v.24 no.4
• /
• pp.225-234
• /
• 2017

Objectives Local gyrification reflects the early neural development of cortical connectivity, and is regarded as a potential neural endophenotype in psychiatric disorders. Several studies have suggested altered local gyrification in patients with bipolar I disorder (BD-I). The purpose of the present study was to investigate the alterations in the cortical gyrification of whole brain cortices in patients with BD-I. Methods Twenty-two patients with BD-I and age and sex-matched 22 healthy controls (HC) were included in this study. All participants underwent T1-weighted structural magnetic resonance imaging (MRI). The local gyrification index (LGI) of 66 cortical regions were analyzed using the FreeSurfer (Athinoula A. Martinos Center for Biomedical Imaging). One-way analysis of covariance (ANCOVA) was used to analyze the difference of LGI values between two groups adjusting for age and sex as covariates. Results The patients with BD-I showed significant hypogyria in the left pars opercularis (uncorrected-p = 0.049), the left rostral anterior cingulate gyrus (uncorrected-p = 0.012), the left caudal anterior cingulate gyrus (uncorrected-p = 0.033). However, these findings were not significant after applying the multiple comparison correction. Severity or duration of illness were not significantly correlated with LGI in the patients with BD-I. Conclusions Our results of lower LGI in the anterior cingulate cortex and the ventrolateral prefrontal cortex in the BD-I group implicate that altered cortical gyrification in neural circuits involved in emotion-processing may contribute to pathophysiology of BD-I.

• Geomechanics and Engineering
• /
• v.30 no.6
• /
• pp.503-515
• /
• 2022

The permeability coefficient is an essential parameter for the study of seepage flow in fractured rock mass. This paper discusses the feasibility and application value of using readily available RQD (rock quality index) data to estimate mine water inflow and grouting quantity. Firstly, the influence of different fracture frequencies on permeability in a unit area was explored by combining numerical simulation and experiment, and the relationship between fracture frequencies and pressure and flow velocity at the monitoring point in fractured rock mass was obtained. Then, the stochastic function generation program was used to establish the flow analysis model in fractured rock mass to explore the relationship between flow velocity, pressure and analyze the universal law between fracture frequency and permeability. The concepts of fracture width and connectivity are introduced to modify the permeability calculation formula and grouting formula. Finally, based on the on-site grouting water control example, the rock mass quality index is used to estimate the mine water inflow and the grouting quantity. The results show that it is feasible to estimate the fracture frequency and then calculate the permeability coefficient by RQD. The relationship between fracture frequency and RQD is in accordance with exponential function, and the relationship between structure surface frequency and permeability is also in accordance with exponential function. The calculation results are in good agreement with the field monitoring results, which verifies the rationality of the calculation method. The relationship between the rock mass RQD index and the rock mass permeability established in this paper can be used to invert the mechanical parameters of the rock mass or to judge the permeability and safety of the rock mass by using the mechanical parameters of the rock mass, which is of great significance to the prediction of mine water inflow and the safety evaluation of water inrush disaster management.

• KSII Transactions on Internet and Information Systems (TIIS)
• /
• v.12 no.6
• /
• pp.2619-2643
• /
• 2018

In this paper, a new clustering algorithm based on the connected region generation (CRG-clustering) is proposed. It is an effective and robust approach to clustering on the basis of the connectivity of the points and their neighbors. In the new algorithm, a connected region generating (CRG) algorithm is developed to obtain the connected regions and an isolated point set. Each connected region corresponds to a homogeneous cluster and this ensures the separability of an arbitrary data set theoretically. Then, a region expansion strategy and a consensus criterion are used to deal with the points in the isolated point set. Experimental results on the synthetic datasets and the real world datasets show that the proposed algorithm has high performance and is insensitive to noise.

• Korean Journal of Cognitive Science
• /
• v.1 no.1
• /
• pp.77-102
• /
• 1989

This paper reports on the development of a recognition system for Korean character,numbers and punctuation marks by syntactic approach after extracting a character or punctuation mark from a page of text.First,using the projection profile(Masudaet.al.1985,Pavlidin 1981)method, we segment a page into different regions of column or row major and then extracts lines of characters from it.Considering the height,width and connectivity of character block,we proceed to extract syllables from the extracted lines.Basically we distinguish syables into six types of formal pattern(남궁재찬 1982,이주근등 1981)following the research of lee and others,and the punctuation marks and numbers into two kinds of formal patterns,and discriminate the surface structure of the extracted syllables.By Index-Removal algorithm,we subdivide them into 44 kinds of basic korean subpattern and special characters (numbers,punctuation marks)and recognize them by syntactic method(이주근등 1981.)

• Bulletin of the Korean Chemical Society
• /
• v.24 no.9
• /
• pp.1265-1268
• /
• 2003

The estimation of retention factors by correlation equations with physico-chmical properties maybe helpful in chromatographic work. The physico-chemical properties were water solubility (S), hydrophobicity (P), total energy ($E_t$), connectivity index 1 ($^1{\chi}$), hydrophilic-lipophlic balance (x) and hydrophilic surface area (h) of isoflavones. The retention factors were experimentally measured by RP-HPLC. Especially, the empirical regulations of water solubility and hydrophobicity were expressed in a linear form. The equation between retention factors and various physico-chemical properties of isoflavones was suggested as $k = a_0 + a_1\;log S + a_2log\;P^Q + a_3(E_t) + a_4(^1{\chi}) + a_5(x) + a_6(h)$, and the correlation coefficients estimated were relatively higher than 0.95. The empirical equations might be successfully used for a prediction of the various chromatographic characteristics of substances, with a similar chemical structure.

• The Korean Journal of Air & Space Law and Policy
• /
• v.22 no.2
• /
• pp.85-108
• /
• 2007

동북아시아지역에서 인천국제공항이 최고의 허브공항으로서 역할을 위해서는 무엇보다도 환승율에 대한 연구가 필요하다고 판단된다. 인천국제공항은 2005년도에 3,054,485만명의 환승여객을 처리하여 환승율은 11.9% 를 기록하였는데 이는 동북아시아의 경쟁허브공항의 환승율인 30-40%와 비교해보면 공항경쟁력이 상당히 뒤쳐진다고 할 수 있다. 이러한 약점을 보완하기 위하여 여러 가지 관련 인자들을 검토하는 것이 중요하다고 판단되어지는데 그중에서 인천국제공항의 비행편최소연결시간(MCT)을 개선하는 것이 필요하다. 이러한 문제를 개선하기 위해서는 항공기 스케줄, 항공사 배치, 게이트 배정방법, 수하물처리, 여객 동선 등이 함께 검토되어야 할 것이다. 그러나 이러한 인자들에 대한 세부적인 분석이 단기간에 걸쳐 해결되는 문제가 아니기 때문에 본 연구에서는 외국 허브공항의 MCT 수준, 관리방법, 국외사례 등을 고찰해 보고 동북아시아에서 허브공항을 향한 인천국제공항의 환승율 제고차원에서 정책적 방안을 제시하고자 한다.

• Korea Trade Review
• /
• v.46 no.1
• /
• pp.113-134
• /
• 2021

This study analyzed the centrality of the GVCs network and the value-added-based production structure of the electrical and electronic industries using ADB-MIRO and social network analysis methods. According to the analysis, the centrality and power of the GVSc intermediate goods network were differentiated into China, the United States, and the EU due to the advancement of industrial structure in Asia. In the 2000 network, the United States and Japan had a very strong influence in all aspects, including connectivity and strength. However, in 2017, China's power index rose to number one among 62 countries in the network. Furthermore, this study presented strategic implications of the Korean electrical and electronic industries to respond to the reorganization of GVSs based on the analysis results.

• Korean Institute of Interior Design Journal
• /
• v.20 no.6
• /
• pp.272-281
• /
• 2011

The purpose of this study is to analyze the correlation between spatial space structure and visitors' behavior and interpret visitors' behavior concretely from the aspect of exhibition environments. So, this study intends to qualify spatial space structure with integration, connectivity and control value by utilizing space syntax, limit to tracking score among the analysis index and reinterpret with exhibition density and extend of eyesight among the exhibition environments. The results of this study are as follows; First, in case of museums, tracking score shows plus correlation with connectivity and control value among the space syntax variables and very low correlation with integration. In case of art museums, tracking score shows plus correlation with integration and wide variable is judged to more useful to analyze visitor's behavior than minor variable. Second, museums doesn't make a great effect on visitors' behavior from the aspect of extent of eyesight, but from the aspect of exhibition density, visitors relatively watched evenly without short cut at the early stage of exhibition in spite of high exhibition density. And, they conducted short cut as they went to the middle stage of exhibition on the course of watching although the numerical value of exhibition density is low. Third, in case of art museums, visitors' behavior was relatively influenced by exhibition density, not extent of eyesight. But, as they went to the high level on the course of watching, watching speed became rapid and watching length became short in the place the value of extent of eyesight was high. Its reason is judged to be easy to grasp position or space structure of the next exhibition room visually. Therefore, when the concentration of watching is necessary from the aspect of exhibition, to control exhibition density properly before the space is useful to draw visiting to exhibition space afterward.