• Title/Summary/Keyword: Architecture Erosion

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EFFICIENT IMPLEMENTATION OF GRAYSCALE MORPHOLOGICAL OPERATORS (형태학 필터의 효과적 구현 방안에 관한 연구)

  • 고성제;이경훈
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.19 no.10
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    • pp.1861-1871
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    • 1994
  • This paper presents efficient real time software implementation methods for the grayscale morphological composite function processing (FP) system. The proposed method is based on a matrix representation of the composite FP system using a basis matrix composed of structuring elements. We propose a procedure to derive the basis matrix for composite FP systems with any grayscale structuring element (GSE). It is shown that composite FP operations including morphological opening and closing are more efficiently accomplished by a local matrix operation with the basis matrix rather than cascade operations, eliminating delays and requiring less memory storage. In the second part of this paper, a VLSI implementation architecture for grayscale morphological operators is presented. The proposed implementation architecture employs a bit-serial approach which allows grayscale morphological operations to be decomposed into bit-level binary operation unit for the p-bit grayscale singnal. It is shown that this realization is simple and modular structure and thus is suitable for VLSI implementation.

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Hydraulic Analysis Using a Two-Dimensional Model(I) : Flow Analysis around Bridge Piers with Pier Shapes (2차원 모형을 이용한 수리해석(I) : 교각형상별 주변부 흐름해석)

  • Kim, Eung-seok;Lee, Seung-hyun
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.16 no.7
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    • pp.4936-4941
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    • 2015
  • This study(I) has analyzed hydraulic characteristics with pier shapes by the bridge construction. The pier shapes are classified into total six types such as square, rhombus, octagon, oval, round, and no-piers. One-dimensional model(HEC-RAS) and two-dimensional model (RMA-2) were employed to analyze hydraulic characteristics around bridge piers. Square and rhombus shapes of piers showed velocity vectors in the upstream direction, which has a significant impact on the river bed changes by erosion and sediment transport around the piers. The flow characteristics of the oval type pier was most similar to that of no-pier situation almost without disrupting the river flow. This analysis can help to select pier types in the new bridge construction for the future.

The Landscape Characteristics of Village Located in the Meander cut-off Area -The Case of Samji Village- (곡류단절지에 입지한 마을의 경관특성 -삼지마을을 사례로-)

  • 임의제;최기수
    • Journal of the Korean Institute of Landscape Architecture
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    • v.28 no.2
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    • pp.108-121
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    • 2000
  • This study seeks what kind of factors influence to locate dwellings and to establish scenic spots in nature by a case study focused on a meandering stream. The study specially concentrates on the interrelationship between both residences and beautiful sceneries and a meander cut-off-area that reveals a special topographical characteristics, located at Samji village in Youngyang-eup, Youngyang-gun, Koungsangbuk-do. The meander cut-off area, developed at the middle or upper reaches of a river, often makes up specific landscapes such as precipitous cliffs, sheer cliffs and caves. And the area where is specially created by sudden change of flow due to erosion ;perceived by the cut surface to be the most beautiful scenic spot. These beautiful landscapes were used to be called as Dae, Dam or Gul and managed by Confucian scholars who enjoy refined taste and devote themselves to the study in nature. Moreover, the Ku-Hado-literary means the area of ex-flow-made the scholars' lving with a well prepared basis for agriculture where supplied a cornucopia of organic matters and water. The merit of agriculture made it possible that the scholars became economically independent, and the fact might be the essential point why the meander cut-off area took noticed. Actually, Cho-family has been in Smaji Village for generations, producing a large number of scholars and keeping the actual power of the region. The physical shape of the meander cut-off area, cozily surrounded by mountains, is considered as a good place for the dwelling due to the influence of traditional sight of view for location and P'ungsuchiri which is known as Feng Shui in China and geomancy in the western world. It is a fruit in it own way that we could find the ancestors' discernment and wisdom from this study, who have lived their lives adapting themselves to the given natural environment and also utilizing the nature wisely. But this is a current-argued study on the meander cut-off area. Follow-up studies have to be continued about the landscapes of the meander streams and the meander cut-off areas scattered all over the country except Samji Village and draw the characteristics from the comparative analysis.

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A Study on the Seeding Mixture Improvements for the Restoration and Revegetation of the Slopes by the Thin-Layer-Soil-Media Hydroseeding Revegetation Measures (생육보조재 취부 공법에 의한 비탈면 녹화 식생배합의 적정성에 관한 연구)

  • Kim, Jung-Hoon;Heo, Young-Jin;Kim, Nam-Choon;Cheong, Yong-Moon
    • Journal of the Korean Society of Environmental Restoration Technology
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    • v.8 no.2
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    • pp.90-97
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    • 2005
  • This study aimed to address problems and suggest solutions in applying seed mixture design criterior of slope revegetation works according to the "Slope revegetation design and guidelines(proposed)" proposed by the Ministry of Construction and Transportation. To do this, a proper thickness of attaching soil media was identified in April experiment where the thickness and slopes varied. The results were as follows. In the test, the coverage rate of plot where exotic grass was not sowed increased with time and was 79.3% after three months of seeding, which indicated less risk of soil erosion. When applying the provisional standards of the plant mix proposed by the Ministry of Construction and Transportation, tree seeds and native plants were found ill in the early stage in all test lands due to exotic grass. This was because exotic grass which grew well in the early stage, could grow densely, so it might hamper the growth of other plants. When slope revegetation were planted and goals were set for herb, shrub and tree dominant mixture types, it was required to shift focus toward nursing up native plants first rather than early plantation of exotic grass.

Rank Decision on Regional Environment Assessment Indicators Using Triangular Fuzzy Number - Focused on Ecosystem - (삼각퍼지수를 활용한 지역환경 평기지표 순위 결정 - 생태계를 중심으로 -)

  • You, Ju-Han;Jung, Sung-Gwan;Park, Kyung-Hun;Kim, Kyung-Tae
    • Journal of Environmental Impact Assessment
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    • v.15 no.6
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    • pp.395-406
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    • 2006
  • This study was carried out to offer the systematical and scientific method of regional environment conservation by deciding the rank using fuzzy theory, and try to find the methodology to accurately accomplished the regional environment assessment for sound land conservation. The results were as follows. To transform the Likert's scale granted to assessment indicators into the type of triangular fuzzy number (a, b, c), there was conversion to each minimum (a), median (b), and maximum (c) in applying membership function. We used the center of gravity and eigenvalue leading to the rank. In the sequential analysis of rank-based test of assessment indicators by triangular fuzzy number, the result proclaimed that ranking of the indicators was, in the biotic field, in the order of 'dominance', 'sociality', 'coverage' and in the abiotic one, 'soil pH', 'T-N', 'soil property', and in the qualitative one, 'impact rating class', 'hemeroby degree', 'land use pattern', and in the functional one, 'protection of water resource', 'offer of recreation', 'protection of soil erosion'. Therefore, there was a difference between subjective rank from human and the rank from triangular fuzzy number. In other words, the scientific rank decision would be not so much being subjective and biased as dealing with human thoughts mathematically by triangular fuzzy number.

A Basic Study on the Development of the Plant-Mat for Ecological Restoration (생태복원용 식물매트 개발에 관한 기초연구)

  • Lee, Dong-Kun;Lee, Joon-Woo;Shim, Sang-Ryul
    • Journal of the Korean Society of Environmental Restoration Technology
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    • v.6 no.2
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    • pp.78-88
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    • 2003
  • This study was conducted to develop the plant-mat for ecological restoration which was formed as the thin multi-layers of woven nets, soil media, seeds, etc. The experimental site was selected at a slope of 240$m^2$ at the rear of Design College of Sangmyung University and divided into 8 sub-experimental plots (20$m^2$ each) according to mat types. (forest-type and grass-type mats with and without seed attachment, respectively) Also, the existing vegetation plot and the no-treatment plot were included in this experiment for comparison. The experiment construction was conducted on September 3, 2002. Mat covered plots regardless of seed attachment showed nearly no signs of erosion even if rainy season in summer compared to the no-treatment plot. Vegetation monitoring result showed that germination rates were somewhat high in both forest and grass-type mats without seed attachment in the initial germination stage. Although germination rates of seed attached mats were somewhat slower than non-seed attached mats in the germination stage, but over time, it showed a good rooting and shooting environment for germinated tree and grass species because of soil media existence within the mat. This indicates that while non seed-attached mats require follow-up maintenance, seed-attached mats does not require maintenance after rooting and germination.

A Study on the Seeding Timing of Native Woody Plants for the Slope Revegetation Works (사면 녹화 공사용 자생목본식생의 파종 적기에 관한 연구)

  • 김남춘
    • Journal of the Korean Institute of Landscape Architecture
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    • v.25 no.1
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    • pp.73-81
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    • 1997
  • This study was conducted to find out the hydroseeding timing of woody plants. Five native plants were used for this experiment and were seeded on the cut slopes by hands in April, May, June, September and October. In order to identify the best seeding time, germination percentage, ground cover rate and plant height were investigated. There was a difference in germination percentage and ground cover rate depending on the seeding time. The results are summerized as follows 1. Characteristics of germination : Seeding was best carried out in spring(May, June) or autumn(September). In spring, Lespedeza cyrtobotrya shows quick germination and rapid growing which can be compared with herbaceous plants using in the hydroseeding. As for Pinus thunbergii, there was little difference in germinatin according to different seeding timing. But Evodia daniellii, Parthenocis년 tricuspidata and Alnus hirsuta seem to need seed treatments to improve the seed germination. 2. Ground cover rate : The most rapid growing plant is Lespedeza cyrtobotrya and the next is Amorpha fruticosa. The other plants show extreamly low ground cover rate, so they seem to be surpressed by herbaceous plants which will be mixed for erosion control. 3. Plant height : On 8 weeks later after seeding, the Lespedeza cyrtobotrya which was seeded in June recorded 17.1cm plant height. It will be enouch height to compete with herbaceous plants. As the Parthenocissus tricuspjdata seeded in May shows 27cm plant length, it can be used more frequently on seeding works if the seed germination were improved. In sum, seeding is best carried out in May. When deciding seeding rate for the purpose of hydroseeding, it will be necessary to adjust the woody plants germination percentage according to seeding timing.

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Seasonal Weight in Seeding Mixture for the Restoration and Revegetation of the Disturbed Slopes (훼손 비탈면의 생태복원녹화를 위한 종자배합량의 계절별 가중치에 관한 연구)

  • Hur, Young-Jin;Ahn, Tae-Young
    • Journal of the Korean Society of Environmental Restoration Technology
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    • v.9 no.1
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    • pp.41-54
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    • 2006
  • In case of leaving artificial slopes resulting from large-scale constructions, there may be secondary damage caused by soil loss due to erosion and collapse. Furthermore, slope-restoring constructions have a few problems such as monotonous landscape and difficult succession of secondary vegetation due to reckless use of exotic grass, despite attaining the initial purpose of revegetation. To settle this problem, selected plants deemed to be proper for revegetation were used on one of thin vegetation base methods, CODRA SYSTEM, and made seeding mixture experimental plots considering germination rates differing in each season. Native herbs, native shrubs and exotic herbs contents were increased by 30% and 50% respectively, centered on seeding quantity(30g/$m^2$) used as design standard in the seed spray method, in order to figure out proper quantity for revegetation in each season.

Measurement and Numerical Model for Wave Interation on Impermeable Steep Slopes (불투수성 급경사면 위의 파랑상호작용에 관한 수치모델 및 실험)

  • Kim, In-Chul;Ahn, Ik-Seong
    • Journal of Ocean Engineering and Technology
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    • v.22 no.5
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    • pp.44-51
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    • 2008
  • The planning and design of coastal structures against wave attack is required to accurately predict wave transformation, wave run-up, and fluid. particlevelocities an a slope. On tire other hand, in tire swash and surf zones of a natural beach, where coastal erosion and accretion occur at tire land-sea boundary, hydrodynamic analysis is essential. In this study, a RBREAK2 numerical model was created based on the nonlinear shallow water equation and laboratory measurements were carried out in terms of tire free surface elevations and velocities for tire cases of regular and irregular waves on 1 : 10 and 1 : 5 impermeable slopes. The data were used to evaluate tire applicability and limitations of tire RBREAK2 numerical model. The numerical mode1 could predict tire cross-shore variation of the wave profile reasonably well, but showed more accurate results for slopes that were steeper than 1 : 10. Except near tire wave crest, tire computed depth averaged velocities could represent tire measured profile below tire trough level fairly well.

Analysis of Shoreline Response due to Wave Energy Incidence Using Equilibrium Beach Profile Concept (평형해빈단면 개념을 이용하여 파랑 에너지 유입에 따른 해안선 변동 해석)

  • Kim, Tae-Kon;Lee, Jung-Lyul
    • Journal of Ocean Engineering and Technology
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    • v.32 no.2
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    • pp.116-122
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    • 2018
  • Dean's equilibrium beach profile formula was used to investigate the correlation between the static shoreline position and the incident wave energy. The effect of the longshore sediment transport was neglected, and the results showed the reasonable agreement compared with the field observations of Yates et al.(2009), which were conducted for almost 5 years on southern California beaches, USA. The shoreline response varies with the scale factor of Dean's equilibrium beach profile. This implies that the shoreline response could be simply estimated using the sampled grain size without laborious long-term field work. Therefore, the present study results are expected to be practically used for the layout design of submerged or exposed detached breakwaters although the further work is required for performance verification. In addition, after laborous mathematical reviews, the linear relation between incident energy and shoreline response, which was obtained from Yates's field study, yielded a clear mathematical equation showing how the beach slope is related to the grain size.