• 산업기술연구
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• 제20권A호
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• pp.123-129
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• 2000

As materials on the river bed have been changing through erosion, transportation and accumulation, so does the waterway's section. So many bridges have nowadays been constructed to the same direction as water flows. However further researches are still needed on the scours of succession row piers and multiple row piers. Analyzing them through hydraulic stimulation experiments, this study deals with the scour character with the change of diameters in row piers which have been built in the identical direction of water flow and also the part-scour character change in multiple row piers.

• The Korean Journal of Ecology
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• 제20권6호
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• pp.439-450
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• 1997

The potential natural vegtation of the Pukhansan National Park area, mid-western Korea, was inferred from the actual vegetation. With the phytosociological classification and field surveys, the actual vegetation map of the park area was made on a scale of 1:25, 000, including fourteen communities. By the analyses of the species diversity, the age structure, the human interferences and various informations on vegetation changes, two pathways of late stage succession from Pinus densiflora forests to the climatic climax were suggested. One is from Quercus serrata forests to Q. mongolica forests throughout the mountain and the other, from Q. variabilis or Q. acutissima forests to Carpinus laxiflora forests in lower parts. Considering the vegetation changes, the potential natural vegetation of the park area mainly composed of Q. mongolica, C. laxiflora, P. densiflora and Zelkova serrata forest as the climatic and/or edaphic climax was inferred.

• Journal of Ecology and Environment
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• 제36권4호
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• pp.267-271
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• 2013

To examine the density effect and food concentration in the competitive output of two Bosmina species, the population growths of Bosmina fatalis were investigated by manipulating the density of B. longirostris and the concentration of algae. The B. fatalis density did not increase in conditions with abundant B. longirostris regardless of the food concentrations. The B. fatalis increased only at low densities of B. longirostris with high food concentrations. Based on the current results, a possible mechanism underlying the seasonal shift from B. longirostris to B. fatalis in Japanese eutrophic lakes will be explored below.

• 복식
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• 제56권7호
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• pp.17-30
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• 2006

The objectives of this study are to research into the traditional costume succession in south and north korea, and to compare similarity and difference of kinds, names, drawing of Jegory. Conclusions are described as follows: 1. In sort of Jegory, south and north korea have same kind of Jegory according to traditional form. But in making method, south korea have pursued various style from traditional type to modern type, north korea have maintained just simple and practical basic style. 2. South and north korea have used same or similar names for the basic part of Jegory. But north korea has made new names for constructional needs, so many differences were shown in the name of details. 3. In drawing of Jegory, north korea has hold traditional method and then tried to seek for rational, scientific technique. Also, due to the influence of south korea that advanced in modern aesthetic, drawing of Jegory in north korea were changed to similar.

• The Korean Journal of Ecology
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• 제15권4호
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• pp.337-344
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• 1992

A study on the secondary succession and species diversity was conducted at burned sites of which pinus densiflora forest and its floor vegetation was almost destroyed by the forest first in the mts. todok, sansong and palgong from 1977 to 1986. The changes of vegetation during period the year to 11th after fire occurred miscanthus sinensis var. purpurascens $\rightarrow$ miscanthus sinensis var. purpurascens-lespedeza cyrtobotyra $\rightarrow$ lespedeza cyrtobotyra $\rightarrow$ lespedeza cyrtobotyra-quercus serrata community. The biological spectra based on $SDR_3$(%) and SP(%) were $H-D_1-R_5-e$ types. The species diversity generally decrease from miscanthus to lespedeza stage and reached minimum at stage of lespedeza, and after that a litter increase for lespedeza-quercus stage. The species distribution curves showed a decrease from miscanthus to lespedeza stage and slight increase at lespedeza-quercus stage in evenness.

• Journal of the korean society of oceanography
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• 제38권3호
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• pp.111-121
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• 2003

The seasonal succession of zooplankton communities in the coastal area off Incheon, Kyeonggi Bay, was investigated with the samples collected at intervals of 10 to 15 days from January 1999 to December 2000. Total abundance of zooplankton communities showed remarkable seasonal variations, ranged from 1,100 to $120,400{\;}indiv./\textrm{m}^3$, and annual mean abundance was $22,000{\;}indiv./\textrm{m}^3$. There were several times of the total abundance during a year, and the timing ofhigh abundances were about the same in 1999 and 2000. During the study period except summer, the abundance of dinoflagellate Noctiluca scintillans and copepod Acartia hongi contributed to the most part of total zooplankton. Whereas, during summer, smaller copepod Oithona davisae and Paracalanus crassirostris were dominant species. Zooplankton communities in the coastal waters off Incheon showed typical characteristics of coastal-estuarine communities, which were dominated by a few species, and abrupt seasonal variations in abundance. We suggest that the seasonal succession and abundance variations of zooplankton communities were caused by the seasonal variations in water temperature and by the seasonally varying phytoplankton biomass in the study area.

• 한국수학사학회지
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• 제26권4호
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• pp.219-232
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• 2013

Japanese mathematics, namely Wasan, was well-developed before the Meiji period. Seki Takakazu (1642?-1708) is the most famous one. Taking Seki's interpolation as an example, the similarities and differences are made between Wasan and Chinese mathematics. According to investigating the sources and attitudes to this problem which both Japanese and Chinese mathematicians dealt with, the paper tries to show how and why Japanese mathematicians accepted Chinese tradition and beyond. Professor Wu Wentsun says that, in the whole history of mathematics, there exist two different major trends which occupy the main stream alternately. The axiomatic deductive system of logic is the one which we are familiar with. Another, he believes, goes to the mechanical algorithm system of program. The latter featured traditional Chinese mathematics, as well as Wasan. As a typical sample of the succession of Chinese tradition, Wasan will help people to understand the real meaning of the mechanical algorithm system of program deeper.

• 대한한의학원전학회지
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• 제26권2호
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• pp.85-103
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• 2013

Objectives : I would find out the developmental succession and results of Li Ting(李梴)'s research for hakgil(malaria, 瘧疾) reflected in Euhakibmun(醫學入門). Methods : I had searched from which books the original contents of Euhakibmun(醫學入門) came, in aspects of classification, causes, mechanism, symptoms, differentiation and medical treatments of malaria. Results : Lee Cheon(李梴) classified causes of malaria from the viewpoint of Yin and Yang, and made its medical treatment modalities definite. He used its prescriptions rationally and analytically according to the classification of malaria which he suggested. Conclusion : Lee Cheon(李梴)'s studies on malaria(瘧疾) in Euhakibmun(醫學入門) were very creative and special unlike existing assessment known in Korean medicine academic world.

• Fisheries and Aquatic Sciences
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• 제2권2호
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• pp.199-209
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• 1999

Before investigating the long-term variations in macrobenthic communities sampled in the Chokchon macrotidal flat in Inchon, Korea, from 1989 to 1996, we need to understand how environmental factors in the area vary. As potential governing agents of tidal flat communities, abiotic factors such as mean sea level, seawater, air temperature, and precipitation were considered. Data for these factors were collected at equal intervals from 1976 or 1980 to 1996, and were analyzed using a decomposition method. In this analysis, all the above variables showed strong seasonal nature, and yielded a significant trend and cyclical variation. Positive trends were seen in the seawater and air temperatures, and based upon this relationship, it was found that the biological sampling period of our program has been carried out during warmer periods in succession. This paper puts forth some hypotheses concerning the response of tidal flat macrobenthos communities to the changing environment including mild winters in succession.

• Ocean Science Journal
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• 제41권1호
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• pp.31-41
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• 2006

Seasonal changes of abundance of the main phytoplankton groups of species (diatoms, dinoflagellates, chrysophytes, small flagellates and cryptophytes) and a set of environmental parameters were investigated in coastal and pre-estuarine waters of Peter the Great Bay (East/Japan Sea) in May-October of 1998 and 1999. Three periods of mass development were revealed: spring, summer and autumn blooms, with successive change of species. The conditions favourable for each group of species were determined. Driving mechanisms of the succession include nutrients transport through seasonal pycnocline by turbulent mixing, terrestrial nutrients supply by monsoon floods, nutrients supply by upwellings, and light control by the thickness of upper mixed layer. Summer succession could be explained by a simple SST-MLD diagram similar to Pingree S-kh diagram with sea surface temperature as indicator of stratification (S) and mixed layer depth as indicator of light availability (kh).