• Journal of the Korean Data and Information Science Society
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• v.27 no.5
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• pp.1155-1168
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• 2016

This paper considers a probability density estimation problem of climate values. In particular, we focus on estimating probability densities of summer extreme temperature over South Korea. It is known that the probability density of climate values at one location is similar to those at near by locations and one doesn't follow well known parametric distributions. To accommodate these properties, we use a mixture of conditional autoregressive species sampling model, which is a nonparametric Bayesian model with a spatial dependency. We apply the model to a dataset consisting of summer maximum temperature and minimum temperature over South Korea. The dataset is obtained from University of East Anglia.

• Journal of the Korean Geosynthetics Society
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• v.5 no.2
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• pp.1-8
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• 2006

The properties of contaminated soil, contaminants and elapsed time are important considering factors to in-situ soil remediation. Gabr et. al. (1996) derived the solution equation of contaminant concentration ratio as initial one ($C/C_0$) with time and spatial changes in contaminated area which are embedded with vertical drains. The contaminant concentration ratio ($C/C_0$) is analyzed with time and spatial changes as varying the effective diameter, porosity, shape factor, density of contaminated soil, temperature in ground, unit weight and viscosity of contaminants by using FLUSH1 model modified from FLUSH. Results from numerical analysis indicate that the most important factor to the in-situ soil remediation in vertical drain system is the effective diameter of contaminated soil. It also shows that the next important factors are the viscosity of contaminants, porosity of soil, shape of soil, temperature in ground, unit weight of contaminants and density of soil, in order. However, the others except the effective diameter of contaminated soil are insignificant to the soil remediation.

• 한국지구물리탐사학회:학술대회논문집
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• 2006.06a
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• pp.155-160
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• 2006

In this paper, we propose a spatial filtering scheme using factorial kriging, one of geostatistical filtering methodin order to separate regional and residual gravity anomaly. This scheme is based on the assumption that regional anomalies have longer distance relation and residual anomalies have effected on smaller range. We decomposed gravity anomalies intotwo variogram models with long and short effectiveranges by means of factorial kriging. And decomposed variogram models produced the regional and residual anomalies. This algorithm was examined using by a synthetic gravity data, and applied to a real microgravity data to figure out abandoned mineshaft.

• Korean journal of applied entomology
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• v.32 no.1
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• pp.61-67
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• 1993

Experiments were conducted to study the functional response of Amblyseius longispinosus Evans to egg densities (10-80) of Tetranychus urtica Koch under different egg distributions (clumped & uniform) and arena sizes (3, 9 & 16 $cm^2$). The searching success of A. longispinosus was affected by the spatial distribution and density of the prey but not by the arena size. there was a highly significant negative correlation (r=-0.85; p=0.0001) between predation amount and distances between preys. The predation response showed a type III functional response. The random predator equation satisfactorily described A. longispinosus predation. The search rate ranged from 0.1030 to 0.1504 under distribution of the prey while it ranged from 0.0546 to 0.276 under uniform distribution.

• Transactions of the Korean Society of Mechanical Engineers
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• v.16 no.12
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• pp.2395-2406
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• 1992

Laminar natural convection heat transfer from a hot body in a square enclosure has been studied for various center positions of a hot body at Grashof number Gr=1.5$\times$10／sup 5／, Prandtl number Pr=0.71 and dimensionless thermal conductivity K／sub s／／K／sub f／= 14710. In case of vertical cold walls, the natural convection at the dimensionless center position of a hot body, X／sub c／Y／sub c／=0.2, 0.5 shows the most strong and at X／sub c／, Y／sub c／=0.5, 0.8 the most weak. In case of horizontal cold walls, the natural convection at the dimensionless center position of a hot body ; X／sub c／ Y／sub c／=0.5, 0.2 shows the most strong and at X／sub c／, Y／sub c／=0.2, 0.5 the most weak.

• Journal of KIISE:Databases
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• v.32 no.3
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• pp.228-242
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• 2005

The projected clustering seeks to find clusters in different subspaces within a high dimensional dataset. We propose an algorithm to discover near optimal projected clusters without user specified parameters such as the number of output clusters and the average cardinality of subspaces of projected clusters. The objective function of the algorithm computes projected energy, quality, and the number of outliers in each process of clustering. In order to minimize the projected energy and to maximize the quality in clustering, we start to find best subspace of each cluster on the density of input points by comparing standard deviations of the full dimension. The weighting factor for each dimension of the subspace is used to get id of probable error in measuring projected distances. Our extensive experiments show that our algorithm discovers projected clusters accurately and it is scalable to large volume of data sets.

• Journal of Korea Water Resources Association
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• v.39 no.2 s.163
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• pp.127-138
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• 2006

This study evaluated the effect of zero measurements of rainfall on the spatial correlation structure using the mixed distribution function. Three cases of data structures were considered at two gauge stations: only the positive measurements at both stations, the positive measurements at either one or both stations, and all the measurements including zero measurement at both stations. Also the rainfall data were categorized into the frontal, typhoon, and convective for their comparison. Hourly rainfall data from 12 rain gauge stations within the Geum river basin were analyzed to find that the rain gauge density of WMO to be good for the frontal and typhoon, but not enough for the convective storms.

• Korean Institute of Interior Design Journal
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• no.18
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• pp.110-116
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• 1999

인류의 역사가 시작된 이후, 인간의 창조는 자연의 모방이라는 큰 울타리 안에서 이루어져 왔다. 신의 작품이 위대한 자연이라면, 인간의 작품은 극히 단순한 그것의 모방에 불과한 것인데, 인간은 인간의 제한된 두뇌 활동으로 이해하기가 불가능한 복잡한 자연을 인식하기 위하여 단순화(simplification)라는 방법을 사용하여 왔다. 이 과정에서 기하학(geometry)은 극도로 발전하게 되며, 인간의 자연 인식을 위한 보편적인 수단으로 자리잡게 된다. 중요한 사실은 기하학이 수단으로서 뿐만 아니라 인간에 의한 창조의 목표로서 위치하게 되었다는 사실이다. 즉 기하학은 자연의 모방이전에 이미 인간의 상상력을 지배해왔고, 그것은 가장 보편적인 창조원리가 되어왔다는 점이다. 그러나 최근의 과학과 기술의 발전, 특히 컴퓨터 기술의 발전으로 그 복잡한 자연은 단순화의 과정을 거치지 않은 복잡한(complex) 상태로 인간에게 이해되어지기 시작했다. 그중 하나가 19세기에 시작된 복잡성(chaos)이론인데 실내공간의 디자인에 있어서도 이러한 자연의 복잡성(complexity)이 새로운 창조 원리로서 자리잡게 되었다. 대표적인 실내 공간 다지이너로서 Nigel Coats를 꼽을 수 가 있는데 그의 무정부적인 (anarchism) 디자인 성향은 자연에서 발견될 수 있는 특징중의 하나라고 할 수 있다. 그가 추구한 복잡성(complexity)은 일본의 동경과 같은 고 밀도(high density)의 적극적 소비 도시(active consuming city)에서 발견되는 지극히 인간적인 도시생활을 만들기 위한 software의 제작이며, 이는 자연이라는 신의 창조물에 근접한 모방이 된다. 본 연구는 Nigel Coats의 작품에서 발견될 수 있는 이러한 무정부주의적 성향이 어떻게 자연의 본질적인 복잡한 (complex) 모습과 관련이 되는가를 통하여 현대 실내디자인의 새로운 방향이 이 시대의 과학적 발견에 따른 복잡성(complexity)과 유관함을 보여준다.

• Journal of the Korean Regional Science Association
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• v.35 no.4
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• pp.33-45
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• 2019

Due to the global low growth trend, urban shrinkage is a major issue of urban policy in major industrialized countries. According to the research results of the KRIHS(Korea Research Institute for Human Settlements, 2016), 23 out of 77 cities in Korea were diagnosed as continuous or temporary shrinking cities. However, the criterion for diagnosing shrinking cities remain on the simple demographic side, and the spatial shrinkage pattern of the city is not considered. Therefore, this study diagnosed urban shrinkage phenomenon considering the characteristics of Yeong-ju, a poly-centric city, by using the population gradient curve, which is one of the urban spatial structure analysis methods. As a result of the diagnosis, Yeong-ju turned out to be a shrinking city with the population density and the slope of population density increasing. In the case of area of Dong, a sprawl phenomenon in which the population density of the CBD and the slope of the population density were decreased was shown. And in the case of Punggi-eup, a simple shrinkage phenomenon in which only the population density of the CBD was decreased was shown. The results show that even within a city, the pattern of spatial change can be different for each centers. In the case of a city with a poly-centric structure, the implications for the individual diagnosis of not only the entire city but also the detailed area were drawn.

• The KIPS Transactions:PartA
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• v.12A no.5 s.95
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• pp.451-460
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• 2005

We present a methodology to design energy-efficient data paths using FPGAs. Our methodology integrates domain specific modeling, coarse-grained performance evaluation, design space exploration, and low-level simulation to understand the tradeoffs between energy, latency, and area. The domain specific modeling technique defines a high-level model by identifying various components and parameters specific to a domain that affect the system-wide energy dissipation. A domain is a family of architectures and corresponding algorithms for a given application kernel. The high-level model also consists of functions for estimating energy, latency, and area that facilitate tradeoff analysis. Design space exploration(DSE) analyzes the design space defined by the domain and selects a set of designs. Low-level simulations are used for accurate performance estimation for the designs selected by the DSE and also for final design selection We illustrate our methodology using a family of architectures and algorithms for matrix multiplication. The designs identified by our methodology demonstrate tradeoffs among energy, latency, and area. We compare our designs with a vendor specified matrix multiplication kernel to demonstrate the effectiveness of our methodology. To illustrate the effectiveness of our methodology, we used average power density(E/AT), energy/(area x latency), as themetric for comparison. For various problem sizes, designs obtained using our methodology are on average $25\%$ superior with respect to the E/AT performance metric, compared with the state-of-the-art designs by Xilinx. We also discuss the implementation of our methodology using the MILAN framework.