• 한국전산유체공학회:학술대회논문집
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• 1995.10a
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• pp.197-202
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• 1995

비정상(unsteady) 압축성(compressible) 유동에 의한 공력음향(aeroacoustics)을 모사하여 공력소음원을 해석하기 위해서는 고차(high order)의 정확도와 높은 해상도(resolution)를 가지며, 상대적으로 계산시간을 많이 필요로 하지 않는 외재적(explicit) 유한차분법이 필수적으로 요구된다. 이것은 주어진 차분방식과 격자계로써 공간과 시간상에 존재하는 미소크기의 파동성분들을 충분히 구현하여야 만족할 만한 수치해를 얻을 수 있기 때문이다. 본 연구에서는, 그러한 유한차분법 중 최근에 관심의 대상이 되고있는 삼각(tridiagonal)또는 오각(pentadiagonal) 집적유한차분법(compact finite difference scheme)이 최대의 해상도를 갖도록 하는 수학적인 방법을 개발하고, 이 방법으로써 새롭게 집적유한차분법을 최적화하였다. 개발된 최적화 방법은, 푸리에 해석법(Fourier analysis)을 통하여 파동수(wavenumber) 영역에서 수학적으로 계산된 위상오차(phase error)를 최소화하는 것이며, 이러한 개념과 방법은 본 연구에서 처음으로 집적유한차분법에 적용되었다. 여러가지 절단정확도(truncation order)에 대해서 최적화 된 집적유한차분법들이 실제 공간과 시간상에서 보여주는 정확도와 오차특성을 알아보기 위하여, 이 방법들을 1차원 선형파동방정식에 적용하였고, 이 결과를 통하여 가장 정확하고 효과적인 절단정확도의 집적유한차분법을 선별하였다. 특히, 오각(pentadiagonal)법에 비해 더욱 효율적인 6차 삼각(tridiagonal)법을 1차원 Euler방정식에 적용하여, 비선형 파동에 대한 모사를 수행할 수 있었다.

• Journal of the Economic Geographical Society of Korea
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• v.3 no.1
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• pp.5-20
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• 2000

Recently as globalization of financial capital is progressed, possibility of crisis and unreliability of world economy is more growing. Korean economy required radical restructuring because of the financial crisis and the economic changes occurred in that process. This study is to explain the economic changes of Gwanagju city is produced by the financial crisis of Korean economy The most important industries are service and transportation equipment in Gwangju city. These industries began to decrease after financial crisis but machinery equipment, electrical machinery & electronics and rubber goods & plastic industry is growing relatively. Because of the decrease of service, the economy of inner city which service industry relatively agglomerated in is reducing. And agglomeration space for the optical photonics industry was built up by the upbringing policy of government on high-technology industry to overcome the economic crisis and micro industrial space such as venture building and establishment nursery center was built up. But high-technology industries have many geographical limits to embed in Gwanagju city, so there needs to construct regional innovation system for knowledge based economies

• Spatial Information Research
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• v.4 no.1
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• pp.55-74
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• 1996

The purpose of this paper is to search the factors which influence the distribution of commercial function. Commercial function plays the most important role in determining urban spacial structure. The location of commercial function is influenced by topography, accessibility, population, and urban policy. Due to the lack of formal data these factors have not been studed to the full. But GIS makes it possible to conduct researches in analyzing these factors. The results are : (1) The index of employment density connects with topography, population, accessibility and urban policy. (2) The location of commercial function is influenced by these factors (3) GIS is a useful tool in analyzing urban spacial structure.

• Journal of the Economic Geographical Society of Korea
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• v.4 no.1
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• pp.37-60
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• 2001

The record industry, which consists of the cultural industries, has been deeply interrelated with the innovations of the science and the technologies. In Korea, the record industry has been developed dramatically since the late 1980s, and thus it has formed a huge business, and has also brought a lot of accompanying economical effects. The record industry is constituted with four circulation steps such as producing, manufacturing, wholesaling and retailing, which follow the different locational orients, respectively. The purpose oi this study is to investigate the locational characteristics of each step. Because of the shortage of the data, this study based on the direct data from field studies, interviews, and surveys, as well as the existing document data. The results of this research are summarized as following: the record industry shows strong concentrations in Seoul and the surrounding areas. It also shows the spatial linkage with other industries that are necessary for the production, advertisement, and sales of records. The locations of the record producers are affected by the location of broadcasting stations. Therefore, they are concentrate in Kangnam and Yeouido, where many broadcasting stations are located.

• Journal of the Korean Geographical Society
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• v.45 no.2
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• pp.256-274
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• 2010

The aim of this study is to examine agglomeration patterns of advertising industries and spatial networks of advertisement production in Korea. The focus of analysis is the agglomeration pattern of advertising industries within Seoul because these are agglomerated in Seoul like other business services. Analysis methods are local Moran's I index and location quotient with the regional percentages of each sector's number of employees. Clusters in Gangnam Area are related to start-up advertising firms and global agencies entering domestic advertising markets. Network analysis is used to investigate the spatial networks of TV advertisement production between advertising agencies(AA) and film productions(FP). After transformation of AA-FP network matrix to regional matrix centrality index and brokerage scores are calculated. This analysis shows individual region's different role and position in the AA-FP network. Many agencies in or out of Gangnam Area outsource most advertisement makings to film productions in Gangnam Area. Advertising industry dusters in Gangnam Area is important as of the destination of advertisement production networks and the circulation of those networks.

• The Journal of the Korea Contents Association
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• v.21 no.3
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• pp.375-389
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• 2021

Recent years have seen a rapid boom of the 4th industry and relevant policies in regions. However there are only a few studies about the impact of the 4th industry on the local economy. This study examines the agglomeration effects of the 4th industry on regional economy by using a spatial statistical models. As a result, it was found that the agglomeration of the 4th industry had a positive effect on the productivity of the local economy, while there is not good enough evidence to prove the relationship between the 4th industry and the income of the region. These findings indicate that the impact of the agglomeration of the fourth industry on the local economy is limited. In addition, the impact on the local economy was different by the type of the fourth industry, and the manufacturing industry and financial and insurance industries had a positive impact on the growth of the local economy.

• Journal of the Economic Geographical Society of Korea
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• v.14 no.4
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• pp.671-683
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• 2011

The technical development of transportation and communication increases freedom of location choice. This higher freedom allows to company can pursues bigger profit than before. Company's separated spatial configurations tend to go to most optimal location, so some places showed unexpected agglomeration. This study conducted to prove "dispersed concentration" for specific example, pharmaceutical enterprises, in real business world. As a result, separation of spatial configuration clearly observed as product output goes bigger and R&D's depth goes deeper. And spatial concentration of each function was found. Most headquarters are located in Seoul, R&D centers make agglomeration at some spaces. Plants' location concentrated until 1990s, but, in 2000s, plants expand out of metropolitan area.

• Korean Architects
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• no.3 s.85
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• pp.22-25
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• 1976

• Journal of the Korea Institute of Information and Communication Engineering
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• v.19 no.3
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• pp.659-666
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• 2015

In this paper, we propose a novel reconstruction method of spatially filtered 3D images in integral imaging based on parallel lens array. The parallel lens array is composed of two lens arrays, which are positioned side by side through longitudinal direction. Conventional spatial filtering method by using convolution property between periodic functions has drawback that is the limitation of the position of target object. this caused the result that the target object should be located on the low depth resolution region. The available spatial filtering region of the spatial filtering method is depending on the focal length and the number of elemental lens in the integral imaging pickup system. In this regard, we propose the parallel lens array system to enhance the available spatial filtering region and depth resolution. The experiment result indicate that the proposed method outperforms the conventional method.

• Korean Journal of Optics and Photonics
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• v.7 no.4
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• pp.333-340
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• 1996

We have implemented a planar integrated optics for the fractional Fourier transform (FRT) which has recently been developed as a generalized form of the conventional Fourier transform. FRT optical systems provide versatile tools for analyzing signals and designing hardwares, but require high accuracy and stability in the arrangement of optical components because of their shift-variant characteristic. The planar optical FRT setup composed of free-space optical components integrated on a single glass block makes the FRT of 2-dimensional(2-D) input patterns through the 3-D glass-space. Therefore, taking advantage of the compactness, easy alignment and thermal/mechanical stability, the planar optics can provide a useful approach to realizing an optical fractional correlation system in a practical way. In the experiment, we have obtained accurate FRT results by using the planar integrated optics with 4 different fractional orders of 0.25, 0.5, 0.75, and 1.0.