• Korean Journal of Organic Agriculture
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• v.8 no.3
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• pp.99-109
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• 2000

This experiment was conducted to investigate the changes of rate of infected common scab and yield characteristics of fall potato(Solanum tuberosum L.) where green manual crops had been previously cultivated, crushed and tilled and P\ulcornerE transparent vinyl film had been mulched and tunneled to solar heating of soil from May 21. 1998 to July 28. 1998. The total yields of green manual crops which had been previousely cultivated were as followed order : pioneer 855F(64.3MT/ha), soybean(25.0MT/ha), red clover and orchardgrass. The average below-ground temperature at the depths of 5, 10 and 20cm were 54, 45 and 44$^{\circ}C$ during the mulching period, respectively The rate of infected area per potato tuber of common scab decreased by solar heating the soils with mulching after the soybean and red clover cultivation as with previous croppings. Plant height, SPAD(soil plant analysis development) reading, fresh weight of stems, and fall potato's tuber yields tended to increase by the cultivation of green manual crops and mulching of P\ulcornerE film. Fall potato's tuber yields were remarkably affected in the plot of soybean, red clover and pioneer 855F+cultivation of fall potato. T-N, K and Ca contents of fall potato(stem and tuber) also tended to increase by the cultivation of green manual crops and mulching of P\ulcornerE film. T-N, K and Ca contents of soil tended to increase after the cultivation of green manual crops and mulching of P\ulcornerE film and then reduced to contents of soil before green manual planting after potato harvesting.

• Korean Journal of Soil Science and Fertilizer
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• v.42 no.4
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• pp.289-300
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• 2009

Flora distribution was surveyed in the newly reclaimed tidal flats in the west coastal area in Korea to understand changes in flora dynamics after reclamation. The surveyed reclaimed tidal flats were the newly reclaimed tidal flat in Hangdam, the mid Kyonggi Bay in 2002, and three reclaimed lands in Seukmun and Daeho, Chungnam, and Hangdam in Kyonggi Bay, of which reclamation years based on embankment were 7, 9 and 18 years, respectively. In the newly reclaimed tidal flat, the dominant flora was Suaeda japonica and other florae were rare, while various halophytes and glycophytes were distributed in the reclaimed lands. On the newly reclaimed tidal flat, four species of halophytic pioneer florae, Salicornia europaea, Suaeda glauca, Suaeda japonica, and Suaeda maritime occurred, and along with age facultative halophyte and glycophyte occurred sequently. On the reclaimed lands, the florae were more complex with various facultative halophyte and glycophyte, so these were predominated rather than pioneer halophyte, while one of pioneer halophyte that Suaeda japonica was not occurred. Increasing of various facultative halophyte and glycophyte, and decreasing of pioneer halophyte indicated that flora changed toward to increase of facultative halophyte and glycophyte by aged after reclamation. On the newly reclaimed tidal flat the ratio of flora species changed rapidly with the invasion of plant. This implied that the flora had begun to change in the early stage of reclamation. Facultative halophyte and glycophyte started to increase on the early stage of reclamation but relative density and frequency of pioneer halophyte was higher than facultative halophyte and glycophyte. According to the investigation up to 3 years after reclamation, pioneer halophyte predominated on it. Although flora changed, there were common representative halophytes among the reclaimed tidal flats: Salicornia europaea, Suaeda maritima, and Suaeda glauca as pioneer halophyte, Aster tripolium, Sonchus brachyotus, and Phragmites communis as facultative halophytes.

• 한국정보디스플레이학회:학술대회논문집
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• 2004.08a
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• pp.737-741
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• 2004

• Proceedings of the Korean Society of Organic Agriculture Conference
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• 2009.07a
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• pp.149-181
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• 2009

• The Optical Journal
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• s.172
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• pp.14-15
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• 2017

• Journal of Smart Tourism
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• v.1 no.2
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• pp.1-2
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• 2021

• Journal of the Korean Operations Research and Management Science Society
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• v.22 no.4
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• pp.71-80
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• 1997

In this paper, we consider with a market pioneering game among symmetric firms in highly competitive situation. To describe the puzzling situation of timing competition, we construct a dynamic game model and explore the equilibrium solution. As a result, we find a subgame perfect mixed strategy Nash equilibrium conceptually defined by 't$_{0}$ + .elsilon. equilibrium'. Our major finding s include : i) market entry will be occurred in sequential manner even though the condition of each firm is symmetric ii) the optimal timing of market pioneering will be advanced until almost all of the monopolist's profit is dissipated, iii) as the market position of the pioneer is stronger, the timings of the pioneer and the follower are separated, iv) and as the slope of the profit flow is steeper, the entry timing of the two players will be pooled together.

• Journal of Plant Biology
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• v.28 no.3
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• pp.191-198
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• 1985

The processes of vegetation development and interspecific association were studied as a part of a successional study in the sand bars at the Nadgdong River estuary in Korea. The major pioneer plant species in the sand bars were Salsola komarovi, Carex pumila and Cynodon dactylon. In embryonic sand bars, Namusitdeung and Galmaegideung, the processes of vegetation development after colonization by pioneer species were closely interdependent with the development of the sand dune. The vegetation types of embryonic sand bars were divided into two groups: sand dune plants, and annual and perennial forbs. Those of old sand bars, Baeghapdeung and Ogryudeung, were also divided into tow groups: sand dune plants, and salt marsh plants. The results of interspecific association coincided well with the actual distribution of plant communities in the sand bars. The degree of vegetation development in each sand bar agreed with the order of successional stage observed in this study area.

• Journal of Environmental Health Sciences
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• v.33 no.5
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• pp.428-433
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• 2007

To clarify the pioneer group in the development of biofilms in high chlorine residual water, a semi-pilot model system was operated and 16S rDNA V3 targeted PCR-DGGE was submitted. Biofilm formation occurred rapidly in the model of a drinking water distribution system. It reached $10^3\;CFU/cm^2$ or more on the surface of stainless steel, PVC, and galvanized iron in chlorinated (1.0 mg/l) water within a week. Within a week, uncultured Proteobacteria- and Bacillales group-like sequences were detected and Sphingomonas-like sequences were identified from all season and all pipe materials tested. Hence Sphingomonas species were regarded as the potential pioneer group in the development of biofilm in drinking water and this results would be useful for the prevention of biofilm formation and safety of drinking tap water.

• The Korean Journal of Ecology
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• v.14 no.2
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• pp.195-210
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• 1991

The primary succession of the pebble area in gye-bang chon, an upper stream bank of north han river, was investigated by belt transect method from July to October 1990. The stsges of bare area, herbaceous pioneer, perenial herb, woody plants and pine stand were recognized from stream bank to inland. The change of the coverage in herbaceous plants increased with developing sueccessional sere but decreaser with increment of woody plants. The species sequence cyrves vs. relative coverage were geometric in pioneer stage and graduaiiy changed to lognormal y\type as the development of forest. The species diversity was highest during then woody plants stage, probably it would to be the edge effect. The soil properties were not noticeable difference between stream side and inland side. It seems that the vegetational developement was not enough to affect soil accumulation.