• Title/Summary/Keyword: 입도 분포

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Direction Recognition of Tongue through Pixel Distribution Estimation after Preprocessing Filtering (전처리 필터링 후 픽셀 분포 평가를 통한 혀 방향 인식)

  • Kim, Chang-dae;Lee, Jae-sung
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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    • 2013.10a
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    • pp.73-76
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    • 2013
  • This paper proposes a tongue and its direction recognition algorithm which compares and estimates pixel distribution in the mouth area. As the size of smart phones grows, facial gesture control technology for a smart phone is required. Firstly, the nose area is detected and the mouth area is detected based on the ratio of the nose to mouth. After detecting the mouth area, it is divided by a pattern of grid and the distribution of pixels having the similar color to the tongue is tested for each segment. The recognition rate was nearly 80% in the experiments performed with five researchers among our laboratory members.

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Characteristics of Particle Size Distribution and Heavy Metal Concentration in Pavement Road Runoff (포장지역 강우유출수에서의 입자성물질의 입도 분포 및 중금속 특성에 관한 연구)

  • Park, Hai-Mi;Kim, Young-Jun;Ko, Seok-Oh
    • International Journal of Highway Engineering
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    • v.11 no.3
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    • pp.141-149
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    • 2009
  • Objective of this study was to characterize the particle size distribution(PSD) and quantify the pollutant concentration in highway runoff. Runoff samples during two rainfall events at four road sites in Gyunggi-Do were collected and PSD and associated pollutant distribution was quantified. Also, rainfall amount, flow rate, and other pollutants in samples were analyzed. PSDs in each sample were analyzed and compared with temporal trends of other pollutants. High partial event mean concentrations(PEMC) of particulates were observed at the beginning of runoff and rapid decrease thereafter. Other pollution parameters such as turbidity, TSS, BOD, TN, and TP also have similar temporal runoff trend with the PEMC. Especially PEMC was well correlated with total suspended solids(TSS) and turbidity. Cu, Pb, Zn had high concentration both runoff and sediment. Heavy metals in sediment were strongly bound to fine particles that have the large surface area-to-volume ratios.

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A Numerical Model for Bed Elevation Change and Bed Material Sorting in the Channel of Non-uniform Sediment (혼합사로 구성된 하천에서 하상변동 및 유사의 입도분포 계산을 위한 수치모형 개발)

  • Jang, Chang-Lae;Jung, Kwan-Su;Kim, Jae-Han
    • Journal of Korea Water Resources Association
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    • v.37 no.5
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    • pp.387-395
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    • 2004
  • A computer model was proposed to simulate channel changes and bed material sorting of the meandering channels with different grain size in time and space simultaneously. The bed at the outside of the meandering channel with mixed sediments was scoured deeply and composed of coarser materials, and at the inside was aggradated and composed of finer materials. The sorting process started at the upstream inflection point and was finished at the downstream inflection point. At the natural with complicated boundaries and non-uniform grain sizes, the bed near the outside at the bend and narrow width was scoured deeper with coarse materials than in the channel with uniform grain sizes. The point bars showed lip at the inside near the bend and the bed materials were finer The bed at the outside near the bend and in the narrow width was scoured deeply with the coarser materials.

A Study on Desulfurization Efficiency of Limestone Sludge with Particle Size (석회석 슬러지의 입도제어에 따른 배연탈황효율에 관한 연구)

  • Seo, Sung Kwan;Chu, Yong Sik;Shim, Kwang Bo
    • Resources Recycling
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    • v.24 no.6
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    • pp.17-23
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    • 2015
  • Flue gas desulfurization(FGD) is the technique to remove $SO_2$ gas from stack gases of coal-fired plants. Many researcher have studied to replace the desulfurizing agent because FGD systems use a lot of limestone and energy. In this study, we use the limestone sludge which is a by-product of steel industry in order to replace desulfurizing agent of FGD system by control the particle size of limestone sludge. And desulfurization performance test is implemented by investigating $SO_2$ gas removal properties upon the characteristic of the limestone sludge with various particle size.

Estimating Hydraulic Properties of Soil from Constriction-pore Size Distribution (수축공극크기분포를 이용한 지반의 수리학적 물성치 산정)

  • Shin, Hosung
    • Journal of the Korean Geotechnical Society
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    • v.38 no.3
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    • pp.27-34
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    • 2022
  • Since water flow in the ground depends on the pore structure composed of soil grains, equations to predict the hydraulic properties based on the grain size have low accuracy. This paper presents a methodology to compute constriction-pore size distribution by Silveria's method and estimate saturated and unsaturated hydraulic properties of soils. Well-graded soil shows a uni-modal pore size distribution, and poor-graded soil does a bimodal distribution. Among theoretical models for saturated hydraulic conductivity using pore size distribution, Marshall model is well-matched with experimental results. Model formulas for soil-water characteristic curves and unsaturated hydraulic conductivity using the pore size distribution are proposed for hydraulic analysis of unsaturated soil. Continuous research is needed to select a model suitable to estimate hydraulic properties by applying the developed model formulas to various soils.

광양만 표층퇴적물의 특성과 저서환경

  • 현상민;이태희;최진성;우한준;최동림
    • Proceedings of the Korea Society of Environmental Biology Conference
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    • 2002.11a
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    • pp.46-50
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    • 2002
  • 광양만의 저서환경을 평가하기 위하여 광양만 표층퇴적물에 대한 퇴적학적, 지화학적 특성을 연구하였다. 입도분석결과 표층퇴적물의 입도특성 분포는 사질퇴적물과 점토질 퇴적물이 다양하게 분포하고 있는 것으로 나타났다. 사질을 포함하는 퇴적물은 주로 POSCO 우측해역과 남해도 사이의 수로 중앙부분에 분포하고 있으며, 그외 지역에서는 점토질 퇴적물이 주를 이룬다. 유기물(TOC) 함량은 약 0.2-2.1%의 범위로 분포하고 있으며, 유기물의 C/N비에 근거한다면 육지에서 공급된 유기물과 현장에서 생성된 유기물이 혼합되어 있음을 지시하고 있다. 저질의 건강상태를 검토하기 위해 퇴적물중의 황화수소(H$_2$S)을 측정한 결과 최고 301 ppm에서 최소 0.7 ppm으로 나타났다. 전체적으로는 묘도안 쪽에서 비교적 높은 값을 보이고 있어 일반적으로 오염된 저서환경이라고 할 수 있다. 기존에 조사된 중형 저서생물의 개체수(species abundance)에 대한 공간분포면화를 조사해본 결과 묘도안쪽에서 낮은 개체수(species abundance)와 종수(species richness)를 보이고 있어 황화수소가 높게 나타나는 지역과 대략적으로 일치하고 있음을 보인다. 추후 저서생물의 다양도나, 저서오염지수(Benthic Pollution Index. BPI)등과 퇴적물증의 유기물이나 황화수소값이 어떻게 관련되는지에 대한 자세한 연구를 필요로 한다.

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Test method of powder properties for electronic ceramics (전자 세라믹 분체의 특성 평가 방법)

  • 엄우식;이인식
    • Electrical & Electronic Materials
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    • v.8 no.3
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    • pp.372-381
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    • 1995
  • 본 논문에서는 분체 특성 평가 연구의 국제 동향과 입자형태, 입도분포, 비표면적, 분체밀도, 기공도, 화학분석 평가분야의 기본원리, 특히 측정시 변수들의 영향과 이러한 특성변화에 따른 전기적성질 변화에 대하여 간단히 언급을 하였다. 분체 특성평가분야의 연구는 선진국에 비해 낙후되어 있고 관심도 또한 낮은 형편이다. 이 분야의 학문적, 산업적인 중요점을 고려할 때, 분체 특성 평가에 대한 기초 및 응용연구가 활성화되었으면 한다.

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Distribution of Heavy Metal Concentrations in Surface Sediments of the eastern Yellow Sea (황해 동부해역 표층퇴적물의 중금속 농도 분포)

  • SUN, CHUL-IN;PARK, GEON-WOO;PARK, HYEON-SIL;PARK, JUN KUN;KIM, SEONG GIL;CHOI, MAN SIK
    • The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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    • v.23 no.4
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    • pp.179-191
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    • 2018
  • In order to determine the distribution characteristics of the heavy metals in surface sediments of the eastern Yellow Sea, heavy metal concentrations (Cu, Pb, Zn, Cd, Cr, Mn, As, Ni, Co, Li, Fe and Al) together with grain size and total organic carbon (TOC), were analyzed. The concentrations of all heavy metals, with the exception of Pb, Mn and As in some stations, were relatively high in the central area of the Yellow Sea and tended to decrease toward the Korean coast. A significant relationship between grain size and concentrations of heavy metals suggested that they were mostly controlled by quartz dilution effect. However, at some stations, Pb, Mn and As exhibited different distribution patterns. For Pb, the differences were caused by petrogenetic influences (feldspar) in coarse-grained sediments. In the case of Mn, biogenetic influences ($CaCO_3$) affected distribution patterns. As was distributed differently because of the existence of a heavy mineral (pyrite). A comparison with previous data (collected in 2000) shows that the heavy metal concentration in the eastern Yellow Sea has not increased over the past fifteen years. The sedimentary environment of dumping sites in the Yellow Sea has not been significantly improved during this period. The results of the pollution assessment revealed that the concentrations of heavy metals in the study area were lower than lower criteria (TEL, MSQ-1) in Korean and Chinese sediment quality guidelines. The enrichment factor (EF), geo-accumulation index ($I_{geo}$) and ecological risk index (ERI) of Cu, Pb, Zn and Cr were higher in the central area of the Yellow Sea.