• 제목/요약/키워드: depth-related distribution

검색결과 248건 처리시간 0.021초

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

  • 유우준;유홍선
    • 한국화재소방학회논문지
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    • 제30권2호
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    • pp.62-67
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    • 2016
  • 본 연구에서는 워터 커튼용 노즐(Water curtian nozzle)의 액적 크기 분포(droplet size distribution)에 따라서 복사열을 감쇄하기 위한 광학 두께(optical depth)를 분석하였다. 액적 크기 분포를 측정하기 위해서 HELOS/VARIO 물 입자 측정 장치를 사용하였으며, Deirmenjian의 수정된 감마 분포 함수(modified gamma distribution function)를 적용하여 분사 특성을 정량화 하였다. 본 연구에서 사용한 워터 커튼용 노즐은 분포 상수(distribution constant) ${\alpha}=1$, ${\gamma}=5.2$의 값으로 나타났으며, 액적의 밀도 수(number density)를 고려한 분포 하중(droplet loading)과 액적 크기 분포 변화에 따라서 광학 두께에 관한 일반화된 관계식을 제시하였다. 본 연구 결과는 워터 커튼용 노즐의 설계 조건을 분석하기 위한 유용한 연구 자료가 될 것으로 사료된다.

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

  • 홍우용;신형진;김성준
    • 한국관개배수논문집
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    • 제14권2호
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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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신갈나무와 상수리나무 숲에서 細根의 空間分布 (Spatial Distribution of Fine Roots in Quercus mongolica and Quercus acutissima Stands)

  • Kwak, Young-Se;Kim, Joon-Ho
    • The Korean Journal of Ecology
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    • 제17권2호
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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
    • 생태와환경
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    • 제38권spc호
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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.

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

  • 유성규;박경양;유명숙
    • 한국해양학회지
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    • 제12권2호
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    • pp.75-81
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    • 1977
  • 피조개는 우리나라의 내만이나 내해의 비교적 수심이 깊은 곳에 사는 대형종으로 조개류 중에서 가장 값비싼 중요양식종이다. 이 종의 양식을 위한 관심이 컸고, 많은 노력도 해 왔으나 양식의 기본이 되는 종묘생산이 제대로 되지않아 그 양식은 언제나 형식에 지나지 않았다.

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

  • 정해근;이충일;박현제;박주면
    • 한국어류학회지
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    • 제32권3호
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    • pp.148-159
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    • 2020
  • 본 연구는 동해 중부 연안에 서식하는 명태의 연직 분포와 개체 크기의 계절 및 연간 변화를 분석하였다. 2016년 1월부터 2018년 2월까지 채집된 명태 개체의 전장은 16.6 cm~81.5cm 범위를 나타내었으며, 50~600 m 사이의 수심대에서 어획되었다. 이 중 25~35 cm 그룹이 차지하는 비율은 45.5%, 35~45 cm 그룹이 차지하는 비율은 27.2%를 나타내며 높은 비율을 차지하였다. 평균 전장은 1월에 가장 크고, 6월에 가장 작았으며, 6월 이후 점차 증가하는 계절주기 변동 특성을 나타내었다. 25 cm 미만 그룹은 100~200 m 수심에 서식하는 비율이 겨울철에 가장 높으며, 이후 봄, 여름, 가을에는 보다 깊은 수심으로 주 서식처를 변화하여 400 m 이상 수심에서 서식하는 비율이 40% 이상을 차지하였다. 25~35 cm와 35~45 cm 개체 그룹의 겨울철 연직 분포는 400 m 이상 수심에서 서식하는 비율이 45% 이상을 기록하였으며, 봄과 여름에는 보다 얕은 수심영역으로 서식처를 변화하여 200 m 미만 수심에서 서식하는 비율이 증가하였다. 이후 가을부터는 다시 서식하는 수심대가 깊어져 300 m 이상 수심의 비율이 증가하였다. 45 cm 이상 개체 그룹은 뚜렷한 계절 변동성을 나타내지 않으며 300 m 이상 수심에서 서식하는 비율이 가장 높았다. 이러한 명태의 연직 분포는 서식처의 물리적 환경 변화에 영향을 받는다. 특히, 상층부의 수온이 상승하고 수온약층 아래 100~300 m 수심대의 수온이 하강한 시기에는 300 m 이상의 깊은 수심대에서 어획되는 비율은 감소한 반면, 수온이 하강한 100~300 m 수심대에서 어획되는 비율이 증가하였다.

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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    • 제30권5호
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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.

한국 남서부 갯벌의 저서성 미세조류의 대상분포와 수직분포에 미치는 이화학적 요인의 효과에 관한 비교 (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)

  • 이학영
    • 한국환경과학회지
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    • 제11권6호
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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.

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

  • 김삼곤
    • 수산해양교육연구
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    • 제20권1호
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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
    • 유통과학연구
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    • 제20권8호
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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.