• Title/Summary/Keyword: Annual plants

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The Role of Phosphorus on Plant Succession of Grassland in Andosol Region I. P-cycle in annual and perennial plant communities (강산성 화산회토양에 있어서 초원의 천이에 미치는 인산의 역할 I. 일년생 및 다년생 목초 군락에 있어서 인의 순환)

  • Chung, Chan;Sugawara, Kazuo;Jean, Byong-Tae
    • Journal of The Korean Society of Grassland and Forage Science
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    • v.12 no.3
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    • pp.145-152
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    • 1992
  • Phosphorus(P) cycle of Miscanthus sinensis, Sasa palmata and Artemicia princeps for perennial plants and Polygonwn thunbergii for annual plant were investigated in natural plant communities established in Andosol region. 1. Perennial plants contained about 50-80 % P of the maximum accumulated in whole plant in under ground parts as reserve P before wintering. On the other hand, annual plant returned the most part of P in plant tissues to soil and wintered with a small amount of P in only seed. 2. The storage percentage of K was low compared to P in both perennial and annual plants. And the return of K from litter to soil proceeded rapidly because of easy leaching of K. 3. Perennial plants stored a large amount of P in reserve organs before wintering and carry it over next generation, and P holded in an individual showed a yearly increase. Consequently, P was less susceptible to depressive factor for growth of perennial plants even in poor P circumstances like Andosol region, compared to annual plant.

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Enhancing Enzymatic Saccharification by Aqueous Ammonia Soaking Pretreatment on Several annual plants (일년생 바이오매스(옥수수 줄기, 담배 줄기, 대마 목부)의 암모니아 침지 전처리가 효소 당화에 미치는 영향)

  • Shin, Soo-Jeong;Yu, Ju-Hyun;Park, Jong-Moon
    • 한국신재생에너지학회:학술대회논문집
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    • 2009.06a
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    • pp.418-421
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    • 2009
  • Effects of aqueous ammonia soaking to three annual plants (hemp woody core, tobacco stalk and corn stover) awere investigated to focus on the enzymatic saccharification characteristics change by this treatment. At two different levels of treatment ($90^{\circ}C$-16 h and $45^{\circ}C$-6 days), higher temperature treatment led to more enzymatic saccharification of cellulose to glucose by commercial cellulase mixtures (Celluclast 1.5L and Novozym 342 from Novozyme Korea). Difference among annual plants were significant. corn stover was the best response to enzymatic saccharification of cellulose and xylan by comercial enzymes all treatment conditions but tobacco stalk was the worst response to all of them. chemical composition or physical structure difference may brought this difference.

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Radiation Exposure from Nuclear Power Plants in Korea: 2011-2015

  • Lim, Young Khi
    • Journal of Radiation Protection and Research
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    • v.42 no.4
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    • pp.222-228
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    • 2017
  • Background: On June 18, 2017, Korea's first commercial nuclear reactor, the Kori Nuclear Power Plant No. 1, was permanently suspended, and the capacity of nuclear power generation facilities will be adjusted according to the governments denuclearization policy. In these circumstances, it is necessary to assess the quality of radiation safety management in nuclear power plants in Korea by evaluating the radiation dose associated with them. Materials and Methods: The average annual radiation dose per unit, the annual radiation dose per person, and the annual dose distribution were analyzed using the radiation dose database of nuclear reactors for the last 5 years. The results of our analysis were compared to the specifications of the Nuclear Safety Act and Medical Law in Korea. Results and Discussion: The annual average per unit radiation dose of global major nuclear power generation was 720 man-mSv, while that of Korea's nuclear power plants was 374 manmSv. No workers exceeded 50 mSv per year or 100 mSv in 5 years. The individual radiation dose according to occupational exposure was 0.59 mSv for nuclear workers, 1.77 mSv for non-destructive workers, and 0.8 mSv for diagnostic radiologists. Conclusion: The radiation safety management of nuclear power plants in Korea has achieved the best outcomes worldwide, which is considered to be the result of the as-low-as-reasonably-achievable (ALARA) approach and strict radiation safety management. Moreover, the occupational exposures were also very low.

A Study on Annual Release Objectives and Annual Release Limits of Gaseous Effluents During Decommissioning of Nuclear Power Plants (원전 해체 시 기체상 유출물의 연간 방출관리치 및 방출한도치에 관한 연구)

  • Lee, Seung-Hee;Hwang, Won-Tae;Kim, Chang-Lak
    • Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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    • v.17 no.3
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    • pp.299-311
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    • 2019
  • Decommissioning is a critical issue in Korea. Although compared with the operation of nuclear power plants the release of radioactive materials during decommissioning is not expected to be significant, residents should always be protected from radiation exposure. To manage this effectively, Annual Release Objectives (ARO) and Annual Release Limits (ARL) were derived from dose standards in the NSSC Notice and dose limit for the public. Based on meteorological data for the three years from 2008 to 2010 in the Shin Kori nuclear power plant site, atmospheric dispersion and ground deposition factors of gaseous effluent were evaluated using the XOQDOQ computer code. The exposure dose was evaluated using the ENDOS-G computer code. Because of differences in radiological sensitivity according to age groups, the results of Annual Release Objectives (ARO) and Annual Release Limits (ARL) showed significant differences depending on the radionuclides. The evaluation methodology of this study will provide meaningful information for radioactive effluent management for decommissioning of nuclear power plants.

Annual Energy Production Maximization for Tidal Power Plants with Evolutionary Algorithms

  • Kontoleontos, Evgenia;Weissenberger, Simon
    • International Journal of Fluid Machinery and Systems
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    • v.10 no.3
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    • pp.264-273
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    • 2017
  • In order to be able to predict the maximum Annual Energy Production (AEP) for tidal power plants, an AEP optimization tool based on Evolutionary Algorithms was developed by ANDRITZ HYDRO. This tool can simulate all operating modes of the units (bi-directional turbine, pump and sluicing mode) and provide the optimal plant operation that maximizes the AEP to the control system. For the Swansea Bay Tidal Power Plant, the AEP optimization evaluated all different hydraulic and operating concepts and defined the optimal concept that led to a significant AEP increase. A comparison between the optimal plant operation provided by the AEP optimization and the full load operating strategy is presented in the paper, highlighting the advantage of the method in providing the maximum AEP.

A Comparison of Nitrogen Cycling among Young Pinus koraiensis Plantations of Different Ages (잣나무 유림의 수령에 따른 질소순환의 비교)

  • Cho, Kang-Hyun;Kim, Joon-Ho
    • The Korean Journal of Ecology
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    • v.12 no.4
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    • pp.245-256
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    • 1989
  • Nitrogen cycling was in vestigated in Piuns koraiensis plantations with different ages, 1, 2, 3, 6, 9 and 11 years, which were reforested after clear-cutting. Annual N input by bulk precipitation was 10kg., and output by runoff decreased as the plantation aged, especially in-N. The standing N content of the whole vegetation increased approximately 5 times through 11 years. Understory surpassed P. koraiensis plants in the distribution of standing N content for the initial 9 years, but reversed thereafter. Annual N uptake of P. koraiensis plants increased greatly through 11 years, but that of understory increased somewhat until 9 years and decreased thereafter. The maximum N uptake of the whole vegetation was made in the 9-yr-old plantation. In the 1-yr-old one, 59% of the maximum was already absorbed by understory which mainly consisted to herbs. The recycling coefficient, ratio of annual return to rptake, of the whole vegetation decreased as the plantation aged and the value of understory was greater than that of P koraiensis plants. On the contrary, the N use efficiency, ratio of the net primary production to N uptake, of the whole vegetation increased as the plantation aged and the value of understory was less than that of P. koraiensis plants. Consequently, it is emphasized that understory played an important role in such plantation reforesred after clear-cutting for the initial 9 years.

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A Study on the Performance Prediction for Small Hydro Power Plants (소수력발전소의 성능예측)

  • Park, Wan-Soon;Lee, Chul-Hyung
    • 한국신재생에너지학회:학술대회논문집
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    • 2005.06a
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    • pp.448-451
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    • 2005
  • This paper presents the methodology to analyze flow duration characteristics and performance prediction for small hydro power(SHP) plants and its application. The flow duration curvecan be decided by using monthly rainfall data at the most of the SHP sites with no useful hydrological data. It was proved that the monthly rainfall data can be characterized by using the cumulative density function of Weibull distribution and Thiessen method were adopted to decide flow duration curve at SHP plants. And, the performance prediction has been studied and development. One SHP plant was selected and performance characteristics was analyzed by using the developed technique. Primary design specfications such as design flowrate, plant capacity, operational rate and annual electricity production for the SHP plant were estimated. It was found that the methodology developed in this study can be a useful tool to predict the performance of SHP plants and candidate sites in Korea.

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Climatic and Environmental Effects on Distribution of Narrow Range Plants (국지적으로 분포하는 식물에 대한 기후 및 환경변수 영향)

  • Kwon, Hyuksoo;Ryu, Jieun;Seo, Changwan;Kim, Jiyeon;Tho, Jaehwa;Suh, Minhwan;Park, Chonghwa
    • Journal of the Korean Society of Environmental Restoration Technology
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    • v.15 no.6
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    • pp.17-27
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    • 2012
  • Climate is generally accepted as one of the major determinants of plants distribution. Plants are sensitive to bioclimates, and local variations of climate determine habitats of plants. The purpose of this paper is to identify the factors affecting the distribution of narrow-range plants in South Korea using National Survey of Natural Environment data. We developed species distribution models for 6 plant species using climate, topographic and soil factors. All 6 plants were most sensitive to climatic factors but less other factors at national scale. Meliosma myriantha, Stewartia koreana and Eurya japonica, distributed at southern and coast region in Korea, were most sensitive to precipitation and temperature. Meliosma myriantha was mostly effected by annual precipitation and precipitation of driest quarter, Stewartia koreana was effected by annual precipitation and elevation, and Eurya japonica was affected by temperature seasonality and precipitation of driest quarter. On the other hand, Spiraea salicifolia, Rhododendron micranthum and Acer tegmentosum, distributed at central and northern inland in Korea, were most sensitive to temperature and elevation. Spiraea salicifolia was affected by mean temperature of coldest quarter and annual mean temperature, Rhododendron micranthum and Acer tegmentosum were affected by mean temperature of warmest quarter and elevation. We can apply this result to future plant habitat distribution under climate change.

Variability in Responses to Phoma medicaginis Infection in a Tunisian Collection of Three Annual Medicago Species

  • Mounawer Badri;Amina Ayadi;Asma Mahjoub;Amani Benltoufa;Manel Chaouachi;Rania Ranouch;Najah Ben Cheikh;Aissa Abdelguerfi;Meriem Laouar;Chedly Abdelly;Ndiko Ludidi;Naceur Djebali
    • The Plant Pathology Journal
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    • v.39 no.2
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    • pp.171-180
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    • 2023
  • Spring black stem and leaf spot, caused by Phoma medicaginis, is an issue in annual Medicago species. Therefore, in this study, we analyzed the response to P. medicaginis infection in a collection of 46 lines of three annual Medicago species (M. truncatula, M. ciliaris, and M. polymorpha) showing different geographic distribution in Tunisia. The reaction in the host to the disease is explained by the effects based on plant species, lines nested within species, treatment, the interaction of species × treatment, and the interaction of lines nested within species × treatment. Medicago ciliaris was the least affected for aerial growth under infection. Furthermore, the largest variation within species was found for M. truncatula under both conditions. Principal component analysis and hierarchical classification showed that M. ciliaris lines formed a separate group under control treatment and P. medicaginis infection and they are the most vigorous in growth. These results indicate that M. ciliaris is the least susceptible in response to P. medicaginis infection among the three Medicago species investigated here, which can be used as a good candidate in crop rotation to reduce disease pressure in the field and as a source of P. medicaginis resistance for the improvement of forage legumes.

A study on the occurrance real status of naturalized plants in urban green space (공원녹지내 사화직물 출현실태 분석에 관한 연구)

  • 노재현
    • Journal of the Korean Institute of Landscape Architecture
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    • v.26 no.3
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    • pp.66-77
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    • 1998
  • The purpose of this study is on identifying real condition of naturalized plants in urban green space. For this, Chollabak-do region was selected for case study. The occurring frequency and distribution status was investigated by field survey. The area of green open space, level of management and passed years after construction etc, were analized to identify the influence on occurrence of naturalized plants. The result is as follows: 1. In 18 sites, 145 taxa as weed species including naturalized plants were occurred. Average No. of occurring taxa is 22.7. Two families of plants, Graminae and compositae charged the most part. Also the rate of naturalized plant among them is 29.7%. 2. Naturalized species showing high occurring rate are 14 taxa of compositae, 5 taxa of Gramineae, Leguminosae and 4 taxa of cruciferae. These plants of previous four somatic polymorphism among all the naturalized plants. 3. The taxa number of naturalized plants were reducedby intensive management. But the rate of naturalized plants in extensively managed area was relatively lower than intensively managed one. Naturalizd plants were widely distributed in most of urban green space with being cognitioned as whole weed. 4. In origin of naturalized plants, the taxa from north America were 16 and the taxa from Europe were 16. Therefore the rate originated from north America and Europe charged high part as 68.2%. The rate of Annual, Biennial and Perennial were each 78.7%, 21.3%. The alternative of management for control aganist disturbance by Annual & Biennial required. 5. Multi-relations analysis shows 0.81 which is the relatively high interralation between the number of emerged axa and that of naturalized ones. 6. The number of naturalized species has no relation to the lapse of years after construction of open-space. Especially it was identified that weed control in the beginning of construction is very important. On the other hand the relation between Ys and Xp was Ys=1.784Xp+4.646.

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