• Title/Summary/Keyword: Distribution patterns

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Studies on the Time Distribution of Heavy Storms (暴雨의 時間的 分布에 關한 硏究)

  • Lee, Keun-Hoo
    • Magazine of the Korean Society of Agricultural Engineers
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    • v.26 no.2
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    • pp.69-84
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    • 1984
  • This study was carried out to investigate the time distribution of single storms and to establish the model of storm patterns in korea. Rainfall recording charts collected from 42 metheorological stations covering the Korean peninsula were analyzed. A single storm was defined as a rain period seperated from preceding and succeeding rainfall by 6 hours and more. Among the defined single storms, 1199 storms exceeding total rainfall of 80 mm were qualified for the study. Storm patterns were cklassified by quartile classification method and the relationship between cummulative percent of rainfalls and cummulative storm time was established for each quartile storm group. Time distribution models for each stations were prepared through the various analytical and inferential procedures. Obtained results are summarized as follows: 1. The percentile frequency of quartile storms for the first to the fourth quartile were 22.0%, 26.5%, 28.9% and 22.6%, respectively. The large variation of percentile frequency was show between the same quartile storms. The advanced type storm pattern was predominant in the west coastal type storm patterns predominantly when compared to the single storms with small total rainfalls. 3. The single storms with long storm durations tended to show delayed type storm patterns predominantly when compared to the single storms with short storm durations. 4. The percentile time distribution of quartile storms for 42 rin gaging stations was estimated. Large variations were observed between the percentiles of time distributions of different stations. 5. No significant differences were generally found between the time distribution of rainfalls with greater total rainfall and with less total rainfall. This fact suggests that the size of the total rainfall of single storms was not the main factor affecting the time distribution of heavy storms. 6. Also, no significant difference were found between the time distribution of rainfalls with long duration and with short duration. The fact indicates that the storm duration was no the main factor affecting the time distribution of heavy storms. 7. In Korea, among all single storms, 39.0% show 80 to 100mm of total rainfall which stands for the mode of the frequency distribution of total rainfalls. The median value of rainfalls for all single storms from the 42 stations was 108mm. The shape of the frequency distribution of total rainfalls showed right skewed features. No significant differences were shown in the shape of distribution histograms for total rainfall of quartile storms. The mode of rainfalls for the advanced type quartile storms was 80~100mm and their frequencies were 39~43% for respective quartiles. For the delayed type quartile storms, the mode was 80~100mm and their frequencies were 36!38%. 8. In Korea, 29% of all single storms show 720 to 1080 minutes of storm durations which was the highest frequency in the frequency distribution of storm durations. The median of the storm duration for all single storms form 42 stations was 1026 minutes. The shape of the frequency distribution was right skewed feature. For the advanced type storms, the higher frequency of occurrence was shown by the single storms with short durations, whereas for the delayed type quartile storms, the higher frequency was shown gy the long duration single storms. 9. The total rainfall of single storms was positively correlated to storm durations in all the stations throughout the nation. This fact was also true for most of the quartile storms. 10. The third order polynomial regression models were established for estimating the time distribution of quartile storms at different stations. The model test by relative error method resulted good agreements between estimated and observed values with the relative error of less than 0.10 in average.

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Delineation Of Coastal Features And Relative Turbidity Levels In The Mid West Sea Of Korea Using Landsat Imagery

  • Youn, Oong Koo;Lee, Byung Don;Kwak, Hi-Sang
    • 한국해양학회지
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    • v.11 no.1
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    • pp.9-17
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    • 1976
  • Multispectral scanner data collected by LANDSAT-1 over the mid West Sea of Korea were analyzed and interpreted for delineation of coastal features and turbidity distribution patterns during different portions of the tidal cycle. Imagery from two successful LANDSAT-1 overpasses of the area in October 1972 and in October 1973 had been used to prepare schematic maps of coastal features and turbidity distributions. Color composite imagery of LANDSAT MSS 4, 5 and 7 gave the best representation of shorelines, coastlines and tidal flats. MSS 5 imagery was most effective in differentiating relative turbidity levels through density slicing techniques. Referring to the tidal power development of Garolim Bay, the basin area measurements assuming dyke construction at the bay entrance, have been carried out on the coastal reature maps comiled from LANDSAT imagery, and those results were correlated with existing data. General areal patterns of surface turbidity distribution in the study area revealed close similarity with bathymetry of the area. Synoptic circulation patterns were also well discriminated from the LANDSAT imagery using the suspended sediment as a tracer.

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Concentration Distribution of Polychlorinated Biphenyls(PCBs) in Urban Watershed (도심하천유역의 PCBs 농도 분포)

  • Kim, Hyun-Seung;Kim, Il-Kyu
    • Journal of Korean Society of Water and Wastewater
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    • v.26 no.6
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    • pp.757-766
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    • 2012
  • In this study, we have examined concentration distribution and patterns of PCBs in waters, sediments and soils in an agricultural area of South Korea to investigate the relationship between PCBs sources and concentration levels. The concentration of PCBs in water samples were ranged from lower values below detection limit to 8.25 ug/L and the concentration of PCBs in sediment samples were ranged from lower values below detection limit to 76.67 ug/Kg. The concentration of PCBs in soil samples were ranged from lower values below detection limit to 23.51 ug/Kg. These contamination levels were far below the guideline values suggested for environmental quality assessment. The homologue patterns in samples varied from sample to sample, but isomer patterns were very similar with each other. PCB-138 and PCB-153 were predominant congeners in the soil and sediment, which were similar to the results obtained from previous studies. With these results, the assessment of potential sources of PCBs contamination in the sediments of the Nakdong river basin was performed. The principal components were extracted by Principal Component Analysis(PCA). As the result of PCA, it could be expected that PCBs in samples of this study were more affected by PCB products than combustion processes and mostly affected by already-known sources. The PCBs in the soil and sediment samples were related with commercial PCB products.

A parametric study on buckling loads and tension field stress patterns of steel plate shear walls concerning buckling modes

  • Memarzadeh, P.;Azhari, M.;Saadatpour, M.M.
    • Steel and Composite Structures
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    • v.10 no.1
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    • pp.87-108
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    • 2010
  • A Steel Plate Shear Wall (SPSW) is a lateral load resisting system consisting of an infill plate located within a frame. When buckling occurs in the infill plate of a SPSW, a diagonal tension field is formed through the plate. The study of the tension field behavior regarding the distribution and orientation patterns of principal stresses can be useful, for instance to modify the basic strip model to predict the behavior of SPSW more accurately. This paper investigates the influence of torsional and out-of-plane flexural rigidities of boundary members (i.e. beams and columns) on the buckling coefficient as well as on the distribution and orientation patterns of principal stresses associated with the buckling modes. The linear buckling equations in the sense of von-Karman have been solved in conjunction with various boundary conditions, by using the Ritz method. Also, in this research the effects of symmetric and anti-symmetric buckling modes and complete anchoring of the tension field due to lacking of in-plane bending of the beams as well as the aspect ratio of plate on the behavior of tension field and buckling coefficient have been studied.

A Study on the Climatic Classification of Korea by the Sensible Degree (체감도에 의한 우리나라의 기후구분에 관한 연구)

  • 설동일;민병은
    • Journal of the Korean Institute of Navigation
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    • v.17 no.4
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    • pp.43-51
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    • 1993
  • The purposes of this study are to make an analysis the sensible degree in Korea by using the formulas prepared by Watanabe, and to divide the climatic classification by the sensible degree in order to apply in practical life. Most data(air temperature, relative humidity, wind velocity, atmospheric pressure) are extracted from the "Climatic Table of Korea, Volume II(1961~1990)" issued by the Korea Meteorological Administration. As a result of this study, distribution patterns of the sensible degree are similar to isotherms when the wind velocity is zero, and then the sensible degrees are reduced with the increase of latitude. And western coastal and inland regions have larger values than eastern coastal regions in summer. However, the cont-rary distributions are shown in winter. When the wind velocity is not zero, distribution patterns of the sensible degree are influenced by the wind velocity. In summer, the values of central and southern inland regions are especially higher than the coastal regions, and most northern districts and some inland regions (Kangnung, Ulchin, Yongju etc.) have low values in winter. Then, the climate of Korea is divided into four patterns as follows : Yow means the sensible degree when the wind velocity is zero in winter. Yow > 3 : Jeju Island and southern coastal regions Yow = 0~3 : Most southern district and eastern coastal regions of central districts Yow = -3~0 : Most central districts and some eastern coastal regions (Hamheung, Youngheung, Won-san etc.) of northern districts Yow < -3 : Most northern districts and some inland regions(Inje, Hongcheon, Yang-pyeong etc.) of cent-ral districts.districts.

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A Study on Spending Patterns and Buying Motives of Indian Gold Consumers

  • Potluri, Rajasekhara Mouly;Ansari, Rizwana;Challagundla, Srilakshmi
    • Journal of Distribution Science
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    • v.11 no.7
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    • pp.31-37
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    • 2013
  • Purpose - The objective of this research is to be acquainted with the spending patterns and buying motives of Indian gold consumers along with the opinions of gold traders. Research design, data, and methodology - The study administers a structured questionnaire survey with 450 consumers and conducts personal interviews with 60 gold businesspersons in the Indian state of Andhra Pradesh, a leading gold consuming state in the entire country. Using Analysis of Variance, the collected data was analyzed and the hypotheses were tested. Results - Results indicate that 85 percent of Indian gold consumers are purchasing gold in the form of ornaments and jewellery as against 10 percent invested in gold coins/bars. Another 5 percent consumers is investing in gold by choosing either gold traded mutual funds or gold schemes introduced by corporate gold traders. Conclusions - Majority of the Indian gold consumers are considering occasions and festivities while buying gold and then giving preference to price as against least preference to recommendations of brand ambassadors.

A Study on the Optimum Synthesis of Line Source Difference Patterns by Sidelobe Level Control (Sidelobe 레벨 제어를 통한 선전원 차패턴 최적 합성에 관한 연구)

  • Park, Eui-Joon
    • Journal of the Institute of Electronics Engineers of Korea TC
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    • v.44 no.6 s.360
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    • pp.57-63
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    • 2007
  • In this paper, a new approach to the optimum synthesis of line source difference patterns is proposed for the monopulse tracking way antennas. In the Proposed scheme, which is different from the well-known Bayliss difference pattern synthesis, the difference patterns with the desired individual sidelobe levels are optimally synthesized by appropriately modifying the Taylor line source sum pattern formula. That is, the relationship between the difference pattern and the corresponding source distribution function is analytically established, and then the desired pattern and the distribution are simultaneously extracted by the optimum perturbation of pattern null positions. Furthermore this method provides more rapid sidelobe decay rates than conventional methods. Some numerical results show the validity and usefulness of the proposed procedures.

A Comparative study on Caregiving and Inheritance patterns; Korea vs. U.S.A (비교문화적 관점에서 본 노부모부양과 재산상속의식: 한국과 미국의 비교)

  • 조병은
    • Journal of Families and Better Life
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    • v.15 no.4
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    • pp.125-136
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    • 1997
  • The present study compares motives for caregiving, actual caregiving provision, care expectation from children in old age, and the connections between caregiving and inheritance distribution patterns as perceived by caregiving daughters/daughters-in-law and their care-receiving mothers/mothers-in-law between Korea and the United States. The results indicated that there was no difference in caregiving motives between Korean and American children while American mothers/mothers-in-law perceived significantly lower obligatory caregiving motives than their Korean counterparts. Also, both Korean children and their mothers/mothers-in-law reported higher level of care provision than their counterparts. The level of caregiving expectation from their children in old age among Korean elders was significantly different from those of American elders while no differences were found between Korean and American children. Finally, both Korean children and their mothers/mothers-in-law were more likely to endorse distributing larger shares of inheritance to the child who cared for his/her mothers/mothers-in-law than American counterparts. On the other hand, American subjects were more likely to accept the notion of equal distribution of inheritance. Overall, this cross-cultural study showed the cultural differences in caregiving and inheritance patterns between Korean and American subjects exhibiting salient difference among the older generation.

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A Study on Kazakh Women's Consumer Behavior

  • Potluri, Rajasekhara Mouly;Abikayeva, Marina;Usmanova, Nelya;Challagundla, Srilakshmi
    • The Journal of Industrial Distribution & Business
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    • v.5 no.4
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    • pp.5-11
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    • 2014
  • Purpose - This paper examines Kazakh women's spending patterns and buying behavior. Research design, data, and methodology - After thoroughly reviewing the related literature on consumer behavior in general, and female consumer behavior in particular, both questionnaires and in-depth personal interviews were used to collect data from 400 Kazakh women consumers equally chosen from the age groups 20-30, 30-40, 40-50, and above 50. Results - A stratified and convenient sample was employed, and the selected five hypotheses were proved using the Karl Pearson Coefficient of Correlation. Related to spending patterns, 40 and 35 percent of the 20-30 and 30-40 age groups, respectively, of Kazakh women spend their incomes on personal items, as against 30 percent from both the 40-50 and 50 and above age groups. Twenty-five and 35 percent of the 40-50 and 50 and above age group, respectively, take decisions based on product quality, whereas this percentage is at its mite in the below 40 age group. Conclusions - The buying behavior of Kazakh women consumers is revealed; the results proffer useful background information to formulate marketing strategies.

Optimal lateral load pattern for pushover analysis of building structures

  • Habibi, Alireza;Saffari, Hooman;Izadpanah, Mehdi
    • Steel and Composite Structures
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    • v.32 no.1
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    • pp.67-77
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    • 2019
  • Pushover analysis captures the behavior of a structure from fully elastic to collapse. In this analysis, the structure is subjected to increasing lateral load with constant gravity one. Neglecting the effects of the higher modes and the changes in the vibration characteristics during the nonlinear analysis are the main obstacles of the proposed lateral load patterns. To overcome these drawbacks, whereas some methods have been presented to achieve updated lateral load distribution, these methods are not precisely capable to predict the response of structures, precisely. In this study, a new method based on optimization procedure is developed to obtain a lateral load pattern for which the difference between the floor displacements of pushover and Nonlinear Dynamic Analyses (NDA) is minimal. For this purpose, an optimization problem is considered and the genetic algorithm is applied to calculate optimal lateral load pattern. Three special moment resisting steel frames with different dynamic characteristics are simulated and their optimal load patterns are derived. The floor displacements of these frames subjected to the proposed and conventional load patterns are acquired and the accuracy of them is evaluated via comparing with NDA responses. The outcomes reveal that the proposed lateral load distribution is more accurate than the previous ones.