• Title/Summary/Keyword: Dispersion index

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A Case Analysis of Volcanic Ash Dispersion under Various Volcanic Explosivity Index of the Mt. Baegdu (백두산 분화 강도에 따른 화산재 확산 사례 분석)

  • Lee, Soon-Hwan;Jang, Eun-Suk;Lee, Hyun-Mi
    • Journal of the Korean earth science society
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    • v.33 no.3
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    • pp.280-293
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    • 2012
  • In order to clarify the characteristics of dispersion of volcanic tephra emitted from the Mt. Baegdu with various eruption environment, numerical analysis were performed using numerical models, Weather Research and Forecast (WRF) and FLEXPART. Synoptic conditions at 12 October 2010 was adopted because the volcanic ash of Mt. Baegdu can reach the Korean peninsula and its dispersion pattern was compared with different Volcanic Explosivity Index (VEI) and particle size. Predominant size of falling out ash flowing in the peninsular is smaller than 0.5 mm and the ash large than the size is difficult to get in the peninsular due to the its weak ability of truculent diffusion. the difference of ash distribution with various VEI scenarios is not so much but number density of ash in the air is dramatically changed. Volcanic ash tends to be deposited easily in eastern coastal area such as Gangneung and Busan, because of the inflow of ash from East Sea and barrier effect of the Taeback mountains along the east coast of the Korean Peninsula. Accumulated amount of ash deposition can be increased in short period in several urban areas.

An Interactive Multi-criteria Group Decision Making with the Minimum Distance Measure (최소 거리척도를 이용한 대화형 다기준 그룹 의사결정)

  • Cho, Namwoong;Kim, Jaehee;Kim, Sheung-Kown
    • Journal of Korean Institute of Industrial Engineers
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    • v.32 no.1
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    • pp.42-50
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    • 2006
  • The multi-criteria group decision making (MCGDM) problem is to determine the best compromise solution in a set of competing alternatives that are evaluated under conflicting criteria by decision maker (DM)s. In this paper, we propose a mixed-integer programming (MIP) model to solve MCGDM. The existing method based on minimizing a distance measure such as Median Approach can not guarantee the best compromise solution because the element of median point vector is defined with respect to each criteria separately. However, by considering all criteria simultaneously, we generate median point that is better for locating the best compromise solution. We also utilize the concept of spatial dispersion index (SDI) to produce a threshold value, which is used as a guideline to choose either the Utopian Approach or the Median Approach. And we suggest using CBITP (Convex hull of individual maxima Based Interactive Tchebycheff Procedure) to provide DMs with various Pareto-optimal solutions so that DMs have broad range of selection.

A Study on Strategy Direction for Promoting the Geo-spatial Information Industry by Input-Output Analysis (산업연관분석을 통한 공간정보산업의 특징 및 정책방향성에 대한 연구)

  • Lim, Si Yeong;Ahn, Jong Wook;Yi, Mi Sook
    • Spatial Information Research
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    • v.20 no.6
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    • pp.69-76
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    • 2012
  • In this study, we derived the characteristics of the geo-spatial information industry by using input-output analysis. For this analysis, we classified the geo-spatial information industry and reorganized the input-output table. And we derived the production inducement coefficient, index of the power of dispersion and index of the sensitivity of dispersion in the geo-spatial information industry. We confirmed that geo-spatial information industry has a small production inducement coefficient and a great forward linkage effect. Based on these facts, we suggested the strategy direction as follows: 1) building the industrial eco-system, 2) managing both advance and applicability enhancement, 3) Establishing from a long-term point of view.

Estimation of Economic Value of the Performance Industry (공연산업의 경제적 파급효과 분석)

  • Bae, Ki-Hyung
    • The Journal of the Korea Contents Association
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    • v.13 no.1
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    • pp.147-155
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    • 2013
  • The purpose of this study is to analyze how much performance industry contribute to national economy by measuring economic effects of performance industry. To achieve the purpose of the study, the study uses an performance industry(theater, music and other arts, 390 sectors) Input-Output Table of yaer 2009 of korea bank. The results shows that performance industry induce 391.6 trillion won in the national production, 65.1 trillion won in the income inducement, 16.3 trillion won in the tax inducement. Especially the performance industry shows that production inducement coefficient is 1,387, Index of the power of dispersion is 0.020, index of the sensitivity of dispersion is 0.025, value-added inducement coefficient is 0.662, income inducement coefficient is 0.455, tax inducement coefficient is 0.046 and employment inducement coefficient is 0.010.

Measurements of Transmittances and Calculations of Fundamental Radiative Properties (투과율의 측정 및 이를 이용한 복사물성치의 계산)

  • Hwang, Yong-Ha;Park, Seung-Ho;Lee, Young-Soo
    • Solar Energy
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    • v.14 no.2
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    • pp.29-37
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    • 1994
  • Radiative charaacteristics of glass windows and porous absorbing media which can be used for a solar air heater are determined through the measurements of spectral transmittances. Those in the visible range are measured by the UV-IR spectrometer. Refractive index of glass are obtained by the comparison of the measured transmittances and the correlations derived from the electromagnetic theory and are compared to the theoretical ones calculated from the classical dispersion theory. Absorption and back-scattering coefficients of 15-mesh stainless wire screens are calcuated by the comparison of the measured transmittances and the correlations derived from the two flux model.

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Measurement of Optical Properties of Nano-Cement Using THz Electromagnetic Waves (THz 전자기파를 이용한 나노시멘트 광학물성 측정)

  • Kim, Heonyoung;Kang, Donghoon;Oh, Seung Jae;Joo, Chulmin
    • Journal of the Korean Society for Nondestructive Testing
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    • v.36 no.5
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    • pp.363-369
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    • 2016
  • Enhancing mechanical strength of concrete has been fascinated using carbon-based nanomaterials such as CNT and graphene. The key to improving strength is a dispersion of nanomaterials. A novel method is required to investigate the dispersion inner concrete nondestructively. In this study, the optical optical properties such as refractive index and absorption coefficient are measured in nano-cement mortar specimens containing MWCNT and GO using THz electro-magnetic waves. From the results, the properties of nano-cement mortar are confirmed to be 1.0% to 2.5% higher in refractive index, and -14% to 28% higher in absorption coefficient than those of cement mortar at the average values. Using these characteristics, visualizing the dispersion of nano-concrete structures seems possible in future.

Correlations between Body Indices and Flow-Volume Curve Parameters (신체지표와 유량-기량곡선 지표간의 상관성)

  • Jin, Bok-Hee
    • Korean Journal of Clinical Laboratory Science
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    • v.41 no.3
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    • pp.135-139
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    • 2009
  • Pulmonary function test has been know to be greatly affected by body indices, such as sex, age, height, body weight, body surface area (BSA) and body mass index (BMI), so hat this study was focused to see the relationship between body index and flow-volume curves. Subjects were 156 (male 90, female 66) and they were examined for pulmonary function test in terms of body index and correlation/multiple regression analysis of flow-volume curves at Presbyterian Medical Center from March to August, 2009. The followings results after analyzing the correlation between body index and flow-volume curves. Although flow-volume curve FEF25-75% showed close correlation with age, body weight, and body surface area, but not with body mass index. In addition, multiple regression analysis was performed to see how each body index affects flow-volume curve FEF25-75%, and FEF25-75% dispersion was explained as 74.5% with age only, 94.2% with age and height, and 96% with age, height, and sex. Therefore, sex, age and height that are mainly used for predictive formular of pulmonary function test and nomogram were important factors for pulmonary function test itself, and further study must be done for other body index.

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Performance Comparison of S-MMA Adaptive Equalization Algorithm by Slice Weighting Value in 16-QAM Signal (16-QAM 신호에서 Slice 가중치에 의한 S-MMA 적응 등화 알고리즘의 성능 비교)

  • Lim, Seung-Gag
    • The Journal of the Institute of Internet, Broadcasting and Communication
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    • v.13 no.3
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    • pp.55-61
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    • 2013
  • This paper compare the performance of S-MMA(Sliced-MultiModulus Algorithm) adaptive equalization algorithm by effect of slice weighting value for the minimization of the distortion and noise in the communication channel.. In the traditional MMA algorithm, the output signal of equalizer and the dispersion constant of transmitting signal is used for calculating the equalizer coefficient, but in S-MMA, the output of equalizer and dispersion constant and the considering the output of decision device by the power of slice constant are used in order to simultaneously compensate the distortion of amplitude and phase distortion. It is confirmed by computer simulation that the slice weighting value affects the performance of adaptive equalization algorithm. The performance index includes the output signal constellation, the residual isi and maximum distortion and MSE that is for the convergence characteristics, the SER according to the signal and noise power ratio at the channel is used. As a result of simulation, the residual isi, maximum distortion and MSE performances are better in the small weighting values. But in SER performance is better in the large weighting values.

An experimental investigation on dispersion and geotechnical properties of dispersive clay soil stabilized with Metakaolin and Zeolite

  • Ahmadreza Soltanian;Amirali Zad;Maryam Yazdib;Amin Tohidic
    • Geomechanics and Engineering
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    • v.36 no.6
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    • pp.589-599
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    • 2024
  • Dispersion occurs when clay soil disperses under specific conditions and is rapidly washed away. While there are numerous methods for rectifying it, they are neither cost nor time-effective. The current study used metakaolin and zeolite to improve heavily dispersive clay soil either separately or in combination at 0%, 2%, 4%, 6%, and 8% of the soil weight. After 7 days of curing, the samples were tested to determine the extent of change in the dispersion potential, as well as the improvement of the geotechnical properties of the soil. The results indicated that the addition of 2% zeolite with 6% to 8% metakaolin decreased the dispersion potential considerably. Double hydrometry test findings revealed that the dispersion potential decreased by almost 70% and entered the non-dispersive group; the crumb test also revealed this. Atterberg limits testing indicated a decrease in the plasticity index which reduced the flexibility of the samples. The greatest decrease in PI (67.5%) was achieved with the addition of 8% zeolite plus 8% metakaolin to the soil. The results of density tests revealed that a decrease in the optimal moisture content increased the maximum dry density of soil. This increase in density was a response to the high reactivity of metakaolin with calcium hydroxide and the formation of calcium hydroxide hydrate gel. This eventually caused an increase in the unconfined compressive strength, the greatest increase in strength of about 1.8-fold was observed with a combination of 2% zeolite and 6% metakaolin compared to the unmodified sample.