• Proceedings of the Korean Institute of Communication Sciences Conference
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• 1984.10a
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• pp.74-77
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• 1984

In this paper, We have proposed the new lee weighted Hadamard transform which retains the main properties of Hadamard matrix. The non-orthogonal LWH matrix was Weighted in the center of the spatial domain. The human visual response to spatioal requencies in nonuniform and that the mid spatial frequencies are emphasized more than the low and high spatial frequencies, the faast algorithm of the Lee Weighted Hadamard transform has shown by the sparse matrix factorization.

• Communications for Statistical Applications and Methods
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• v.17 no.3
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• pp.349-356
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• 2010

The ordinary least squares based estimator of the disturbance variance in a regression model for spatial panel data is shown to be asymptotically unbiased and weakly consistent in the context of SAR(1), SMA(1) and SARMA(1,1)-disturbances when there is measurement error in the regressor matrix.

• Journal of Ecology and Environment
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• v.37 no.2
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• pp.81-90
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• 2014

This study examined the main factors affecting the distribution of Phytolacca americana, an exotic plant species in Korea, in coastal sand dunes. The areas examined from June 2004 to February 2006 were in Sindusagu where was located on Sindu-ri, Wonbuk-myen, Taean-gun, Chungcheongnam-do. The vegetation, sediment properties, sizes and ages of Robinia pseudoacacia, P. americana and Pinus thnunbergii and spatial distribution of P. americana were assessed. Firstly, correlation coefficients (CC) between P. americana's root biomass and sediment properties were not significant. Secondly, of the four community types, P. americana was not in the mixed herbaceous community and its density was the highest in the P. thunbergii-R. pseudoacacia and R. pseudoacacia community The Poisson distribution analysis revealed the distribution of P. americana to be severely clumped. The root biomass of P. americana and the basal area of R. pseudoacacia were significantly correlated, but the CCs between P. thunbergii and other two species were not significant. The ages of P. americana and R. pseudoacacia in a quadrat were significantly correlated. Thirdly, P. americana's ages in a quadrat were mostly similar to each other. Therefore, the spatial distribution of P. americana was largely influenced by R. pseudoacacia but not by the sediment properties, and plants in a narrow area were concurrently germinated.

• Journal of Korean Society for Geospatial Information Science
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• v.13 no.3 s.33
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• pp.15-24
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• 2005

The Land Suitability Assessment(LSA) that was introduced to prevent the unplanned development was viewed from it has applied the same assessment factor on inland and island that has a many different spatial and physical properties, it have many problems. To study the efficient LSA in island that has an totally different spatial, local properties, assessment unit(AU) which the zone of life was considered and on this based, assessment factor was developed. In the AU, middle sized life zone was the best AU to present the regional land properties. In the distance analysis, distance analysis that considered sea was suggested and use it, we ran present the assessment method that was considered the access between islands.

• Spatial Information Research
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• v.16 no.3
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• pp.303-315
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• 2008

This study is aimed at the surveys of cultural relics and GIS based searching system which have been partially performed in each region. The goal of this research is to construct the cultural relics management system of region and to present the plan for a nationwide data integration. Consequently, based on the standard which presents from Cultural Properties Administration constructed a spatial and attribute data. And presented the model which matches national standard for a cultural property GIS integration. Also minimized a damage possibility about the cultural ruins, confirmed an application possibility about cultural ruins information of the local government.

• Water Engineering Research
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• v.3 no.1
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• pp.31-44
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• 2002

The effect of diurnal cycle, intermittent visit of observation satellite, sensor installation, partial coverage of remote sensing, heterogeneity of soil properties and precipitation to the soil moisture estimation error were analyzed to present the global sampling strategy of soil moisture. Three models, the theoretical soil moisture model, WGR model proposed Waymire of at. (1984) to generate rainfall, and Turning Band Method to generate two dimensional soil porosity, active soil depth and loss coefficient field were used to construct sufficient two-dimensional soil moisture data based on different scenarios. The sampling error is dominated by sampling interval and design scheme. The effect of heterogeneity of soil properties and rainfall to sampling error is smaller than that of temporal gap and spatial gap. Selecting a small sampling interval can dramatically reduce the sampling error generated by other factors such as heterogeneity of rainfall, soil properties, topography, and climatic conditions. If the annual mean of coverage portion is about 90%, the effect of partial coverage to sampling error can be disregarded. The water retention capacity of fields is very important in the sampling error. The smaller the water retention capacity of the field (small soil porosity and thin active soil depth), the greater the sampling error. These results indicate that the sampling error is very sensitive to water retention capacity. Block random installation gets more accurate data than random installation of soil moisture gages. The Walnut Gulch soil moisture data show that the diurnal variation of soil moisture causes sampling error between 1 and 4 % in daily estimation.

• Computers and Concrete
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• v.15 no.2
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• pp.231-257
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• 2015

This paper discusses the spatial variability of the carbonation depth caused by the mesoscopic structure of the concrete and the influence of the spatial variability on the thickness of the concrete cover. To conduct the research, a method to generate the random aggregate structure (RAS) based on polygonal particles and a simplified numerical model of the concrete carbonation at meso-scale are firstly developed. Based on the method and model, the effect of the aggregate properties including shape, content and gradation on the spatial variability of the carbonation depth is comprehensively studied. The results show that a larger degree of the spatial variability will be obtained by using (1) the aggregates with a larger aspect ratio; (2) a larger aggregate content; (3) the gradation which has more large particles. The proper sample size and model size used in the analysis are also studied. Finally, a case study is conducted to demonstrate the influence of the spatial variability of the carbonation depth on the proper thickness of the concrete cover. The research in this paper not only provides suggestions on how to decrease the spatial variability, but also proposes the method to consider the effect of the spatial variability in designing the thickness of the concrete cover.

• The Bulletin of The Korean Astronomical Society
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• v.43 no.1
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• pp.60.2-60.2
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• 2018

We present the near infrared JHK photometric properties and the spatial distribution of red supergiants(RSGs) of NGC 3623, NGC 3627 and NGC 3628 in the Leo Triplet system using the data obtained with 3.8m UKIRT(United Kingdom Infra-Red Telescope) at Hawaii. We checked interaction between the three galaxies by making a spatial density map of RSGs. From (J-K,K)0 Color-Magnitude Diagram which include resolved stars in three galaxy and control field with PARSEC isochrone, we figured out the RSG candidates of the Leo triplet are at 0.9<(J-K)0<1.2, mK<17.5 and separated them from background and foreground sources. Using gaussian kernel density estimation, we drew spatial density map of RSGs in the Leo triplet with an assumption that all RSGs are an identical population. The density map shows extended features of NGC 3628 to NGC 3627 along the declination direction. The asymmetries between NGC 3627 and NGC 3628 might be evidence for that the distribution of actual star components(RSGs) follows the neutral hydrogen distribution and also for interaction between two galaxies. And the extended features along the right ascension direction might be a supporting evidence for the existence of a TDG(Tidal Dwarf Galaxy). In case of NGC 3623, we could not see any sign of interaction in density map.

• Journal of the Korean housing association
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• v.22 no.1
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• pp.35-42
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• 2011

The objective of this study is to investigate the functional conformity based on the analysis of the spatial connectivity of block housing using space syntax. Three cases were selected which have important meanings in 1920s. The properties of spatial configuration were derived from an urban-context approach and without urban context analysis, and spatial connectivity and functional conformity were analyzed using references. The results of the study revealed that the arrangement of block housing were different from one another notwithstanding their similar layout characteristics. The relationships between urban streets and housing complexes were identified, and the public spaces were being arranged as semi-public spaces, whereas blocks as private spaces by separating functions. This study provides the implications for the planning of low rise-high density housings by means of analyzing the spatial connectivity of the spatial layout characteristics of European block housing, recognizing the relationships between urban communities and housing complexes.

• Journal of the Architectural Institute of Korea Planning & Design
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• v.36 no.5
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• pp.23-32
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• 2020

Recently, women's fear of crime continues to increase in space of everyday. By the way, the fear of crime has the spatial properties as crime. Therefore, The purpose of this study is to evaluate the spatial dependence of fear of crime and to suggest the physical environmental factors influencing fear of crime. For this, a spatial regression analysis using spatial weights was conducted based on the location data of the fear of crime measured through a survey. The results of this study are as follows; First, the fear of crime felt by women in their twenties who are vulnerable to crime has spatial dependence. Therefore, it is necessary to consider the spatial characteristics in analyzing the environmental factors affecting this. Second, in order to reduce the fear of crime, it is necessary to improve the environments of old housing and entertainment facilities. There is also a need for ongoing management. Third, careful consideration is needed in the installation of CCTV and street lights, which are factors influencing the fear of crime. It is necessary to establish a reasonable arrangement standard for CCTV and to analyze the street lighting in detail.