• 제목/요약/키워드: depth-related distribution

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Analysis on the Relations of Droplet Size Distribution and Optical Depth in Water Curtain (워터커튼에서 액적의 크기 분포와 광학 두께의 상관관계 분석)

  • You, Woo Jun;Ryou, Hong-Sun
    • Fire Science and Engineering
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    • v.30 no.2
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    • pp.62-67
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    • 2016
  • In this study, the optical depth is analyzed with the effects of droplet size distribution of the water curtain nozzle to attenuate the radiative heat transfer. The HELOS/VARIO equipment is used for the measurement of the droplet size distributions. The spray characteristics are quantified by the investigation of Deirmenjian's modified gamma distribution function. The distribution constant of the nozzle can be obtained as ${\alpha}=1$ and ${\gamma}=5.2$. The generalized equation of the optical depth related with the droplet size distribution is introduced. These results will be applicable to the analysis of the design condition of the water curtain nozzle.

Extraction of Snow Cover Area and Depth Using MODIS Image for 5 River Basins South Korea (MODIS 위성영상을 이용한 국내 5대강 유역 적설분포 및 적설심 추출)

  • Hong, U-Yong;Sin, Hyeong-Jin;Kim, Seong-Jun
    • KCID journal
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    • v.14 no.2
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    • pp.225-235
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    • 2007
  • The shape of streamflow hydrograph during the early period of spring is very much controlled by the area and depth of snow cover especially in mountainous area. When we simulate the streamfolw of a watershed snowmelt, we need some information for snow cover extent and depth distribution as parameters and input data in the hydrological models. The purpose of this study is to suggest an extraction method of snow cover area and snow depth distribution using Terra MODIS image. Snow cover extent for South Korea was extracted for the period of December 2000 and April 2006. For the snow cover area, the snow depth was interpolated using the snow depth data from 69 meteorological observation stations. With these data, it is necessary to run a hydrological model considering the snow-related data and compare the simulated streamflow with the observed data and check the applicability for the snowmelt simulation.

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Spatial Distribution of Fine Roots in Quercus mongolica and Quercus acutissima Stands (신갈나무와 상수리나무 숲에서 細根의 空間分布)

  • Kwak, Young-Se;Kim, Joon-Ho
    • The Korean Journal of Ecology
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    • v.17 no.2
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    • pp.113-119
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    • 1994
  • Vertical and horizontal distribution and seasonal changes of fine roots as well as inorganic nitrogen content in soil were determined in Quercus mongolica and Quercus acutissima stands in Mt. Taemosan, Seoul. The vertical distribution of fine rooth phytomass showed a power-functional decrease as descending soil depth. Fine root phytomass was 170 g $DM/m^2$(46%) and 225 g $DM/m^2$(47%) in top soil of 5 cm depth, and 370 g $DM/m^2$ and 480 g $DM/m^2$ from soil surface to 50 cm depth in Q. mongolica and Q. acutissima stands, respectively. Fine roots in relation to the distance from the nearest tree were evenly distributed horizontally in both stands. Fine roots phytomass in top soil of 5 cm depth reached a peak in June, and thereafter decreased gradually in both stands. Patterns of seasonal changes in fine root phytomass were closely related to inorganic nitrogen and moisture content.

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Vertical Migration and Horizontal Distribution of Chaoborus Larvae in Lake Fukami- ike, Japan

  • Nagano, Mariko;Tanaka, Masaaki;Yagi, Akihiko
    • Korean Journal of Ecology and Environment
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    • v.38 no.spc
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    • pp.27-30
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    • 2005
  • Diel vertical migration (DVM) and horizontal distribution of Chaoborus flavicans larvae were studied in Lake Fukami-ike (maximum depth 7.75 m, Central Japan). The larvae showed a clear migration in the 4 ${\sim}$ 7 m layer during the day and throughout the water column at night. It should be noted that, while old instar distributed throughout the column during the night. Young instar was found only in the 1 ${\sim}$ 4 m layer. An examination of horizontal distribution revealed that larval stage was clearly related with the depth. It suggests that Chaoborus appear to exist in the deeper area during the larval stage.

Biological Studies On Arkshell Culture I. Distribution Of Drifting Larvae Of Te Arkshell, Anadara broughtonii Schrenck (피조개의 양식에 관한 생물학적 연구 I.부유유생의 분포)

  • Yoo, Sung Kyoo;Park, Kyung Yang;Yoo, Myung Sook
    • 한국해양학회지
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    • v.12 no.2
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    • pp.75-81
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    • 1977
  • Distribution of drifting larvae of Anadara broughtnoii SCHRENCK was studied based on the planktonic sampling which has been collected in fifteen sampling areas of southern coast of Korea and Ulsan Bay during summer season from 1973 to 1977. Vertical and horizontal occurrence was analyzed related to the environmental factors such as surface water temperature, current velocity and depth of water column. High density of the larvae was observed in the Chinhae Bay which included the sampling areas Rampo, Sockcheon, Majeon, Changpo, Dangdong, Bedun, Changchoa, and Wonmun. Maximum occurrence of the farvae was accompanied with the highest water temperature of the summer season, and it was usually August when the water temperature was over 27$^{\circ}C$. In August, 1975, the highest density of the farvae was observed, when the mean surface water temperature was the highest compared to those of other years. The first appearence of the drifting larvae was also related to the surface water temperature. Each year the larae begin to appear from the late July and the ready-to-fall larvae appear in abundance from the mid-August. Vertical distribution patterns of the larvae are closely related to the depth of the water column as well as to the current velocity. In shallow water the larvae tend to aggregate in the bottom layer, while they are diffused to some extent in deep water. In shallow water column ( 8m) more or less 75% of the total larvae individuals was observed in the lower 4m layer and in deep water column ( 16m) only 45% of those was found in the lower 4m layer. In the water of lower velocity a large fraction of the larvae population is distributed in the lower depth layer.

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Influences of Oceanographic Features on Spatial and Temporal Distributions of Size Spectrum of Walleye Pollock, Gadus chalcogrammus Inhabiting Middle Eastern Coast of Korea (동해 중부 연안 환경 변화에 따른 명태 개체 크기 및 분포의 시공간적 변화)

  • Jung, Hae Kun;Lee, Chung Il;Park, Hyun Je;Park, Joo Myun
    • Korean Journal of Ichthyology
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    • v.32 no.3
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    • pp.148-159
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    • 2020
  • This study investigated the seasonal and inter-annual changes in vertical distribution and size spectrum of walleye pollock, Gadus chalcogrammus inhabiting middle eastern coast of Korea (hear after pollock). Pollock was distributed between 50 m and 600 m depth range, and body size (total length) ranged from 16.6 cm to 81.5 cm. The trends of population body size were increased in autumn and winter and decreased in spring and summer. Vertical distribution of pollock showned depth-dependent patterns with distributing smaller individuals mainly in the upper layer (shallower depth), while larger fish in deeper habitats. Those patterns in vertical distribution of pollock population is probably due to be the results of energy-saving strategy, metabolic effects, and changes in prey selections according to pollock growth, derived from spatial and temporal changes in oceanic condition in habitat grounds. When water temperature in upper layer were increased and that of below thermocline depth became decreased in 2017, the ratio of smaller (<35 cm) and larger (≥35 cm) individuals was biased toward larger fishes, extending their distribution into shallow depth, and consequently main fishing ground was formed in far from coastal area. In addition, the ratio of smaller individual distributing between 100~300 m was increased with decreasing temperature gradient between below thermocline and bottom layer. Changes in spatial and temporal distributions of pollock population likely be related with vertical and horizontal changes in oceanic conditions and, consequently food supplies.

Predicting depth value of the future depth-based multivariate record

  • Samaneh Tata;Mohammad Reza Faridrohani
    • Communications for Statistical Applications and Methods
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    • v.30 no.5
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    • pp.453-465
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    • 2023
  • The prediction problem of univariate records, though not addressed in multivariate records, has been discussed by many authors based on records values. There are various definitions for multivariate records among which depth-based records have been selected for the aim of this paper. In this paper, by means of the maximum likelihood and conditional median methods, point and interval predictions of depth values which are related to the future depth-based multivariate records are considered on the basis of the observed ones. The observations derived from some elements of the elliptical distributions are the main reason of studying this problem. Finally, the satisfactory performance of the prediction methods is illustrated via some simulation studies and a real dataset about Kermanshah city drought.

Comparison of the effects of physico-chemical factors on the zonation and vertical distribution of benthic microalgal communities in the tidal flats of south-west Korea (한국 남서부 갯벌의 저서성 미세조류의 대상분포와 수직분포에 미치는 이화학적 요인의 효과에 관한 비교)

  • 이학영
    • Journal of Environmental Science International
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    • v.11 no.6
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    • pp.529-535
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    • 2002
  • Efffcts of physico-chemical factors on the zonation and vertical distribution of benthic microalgal communities in the tidal flats of Youngkwang and Canaiin, Korea, were studied. Concentrations of nutrients were low throughout the study period. A 38 species of benthic microaigae was identified. Most of the algae were pennate diatoms with small size. Cell numbers at silty sediments were higher than sandy sediments, and showed high patchy distribution. Zonal distributions of benthic microalgae showed higher variation from silty sediment than sandy sediments. Benthic microalgae showed vertical migration within the upper few mm of sediment with periodicity closely related to tidal cycles. Maximum cells were observed from 0 mm depth both sandy and silty sediments. Cells of benthic microalgae in the 1 - 2 mm depth decreased after desiccation of sediments. The variation of cells was higher at sandy sediments than silty sediments. Cell numbers of benthic microalgae showed no positive relationships with pH and nutrinets except NH$_4$-N.

A Study on Prediction and Development of Prospective Fisheries-Related Jobs in Korea (우리나라 수산업의 유망직종 예측과 개발에 관한 연구)

  • Kim, Sam-Kon
    • Journal of Fisheries and Marine Sciences Education
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    • v.20 no.1
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    • pp.36-45
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    • 2008
  • The purpose of this study was to explore new fisheries-related jobs in the future. The study is based on a thorough literature review and in-depth interviews with experts in the fisheries industry. The major findings of the study were as follows: First, new fisheries-related jobs that surpass the fitness rating of 90% and earn more than 3 on the prospect scale are expected to be found mostly in professional fishery sectors. In the production and processing sectors, fishery quality control manager, marine product cooks, and raw fish cooks looked most promising. In the fishery marketing and distribution section, on the other hand, marine tour consultants, marine product distribution consultants, underwater guides, online marine product traders, marine sports consultants, and marine safety specialists ranked high on the list.

Customer's Satisfaction About Mobile Banking Distribution Channel in Vietnamese Commercial Banks

  • NGUYEN, Minh Phuong;PHAN, Anh
    • Journal of Distribution Science
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    • v.20 no.8
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    • pp.69-79
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    • 2022
  • Purpose: In the context of the emergence of industry 4.0, using mobile phones as a modern distribution channel to execute financial services is a significant solution for commercial banks' retail services and a gateway to promote financial inclusion and market development. Despite that service quality and customer satisfaction are two diverse notions and closely related to each other in the service sector, there is hardly a research which empirically examines the impacts of each dimensions of mobile banking service quality and customer satisfaction. Research design, data and methodology: This study first employs in-depth interview to explore various aspects of mobile banking service quality dimensions, including empathy, responsiveness, tangibility, assurance, and reliability that serves to develop measurement scales and hypothesis development. A quantitative survey is followed to collect data from 265 Vietnamese bank customers to empirically test the conceptual model. Resutls: Our findings indicate that more human-related factors including empathy, assurance, and responsiveness show the strongest impacts on customer satisfaction with mobile banking service while tangibility and reliability, as technical aspects, are less influential factors. Conclusions: Finally, some crucial implications are drawn for the banks to manage consumer behavior in mobile banking.