• 제목/요약/키워드: NPP

검색결과 910건 처리시간 0.029초

논벼 NPP 지수를 이용한 우리나라 벼 수량 추정 - MODIS 영상과 CASA 모형의 적용 - (Prediction of Rice Yield in Korea using Paddy Rice NPP index - Application of MODIS data and CASA Model -)

  • 나상일;홍석영;김이현;이경도;장소영
    • 대한원격탐사학회지
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    • 제29권5호
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    • pp.461-476
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    • 2013
  • CASA 모델은 작물의 순 일차생산량(NPP)을 추정하는 가장 빠르고 정확한 모델 중 하나이다. 본 연구의 목적은 (1) 2002년 ~ 2012년 동안 한국의 논지역을 대상으로 작물 NPP의 시공간적 변화 패턴을 분석하고, (2) 연간 NPP와 쌀 생산성 간의 관계를 파악하여, (3) MODIS Product와 태양 복사량을 CASA 모형에 적용하여 2012년 한국의 쌀 수량을 추정하는 것이다. 또한, (4) 통계청이 발표한 최종 수량과 비교를 통해 적용을 검토하였다. 이를 위해, 월별 또는 누적 NPP와 수량과의 상관분석을 실시하였다. 그 결과, 총 누적 NPP와 9월의 NPP가 쌀 수량과 높은 상관성을 나타내었으며, 이를 이용하여 추정한 2012년 예측 수량은 누적 NPP 적용시 526.93 kg/10a, 9월의 NPP 적용시 520.32 kg/10a로 추정되었다. 통계청의 최종 수량과의 RMSE는 각각 9.46 kg/10a, 12.93 kg/10a를 나타내었으나, 전반적으로 두 모형 모두 1:1선에 근접한 결과를 보이고 있어 NPP를 이용한 벼 수량 추정 모형이 논벼 수량의 변화특성을 잘 반영하고 있는 것으로 판단된다.

NOAA/AVHRR 자료를 이용한 순일차생산량 분포 추정 (Estimation of NPP Distribution using NOAA/AVHRR)

  • 신사철;유철상
    • 한국환경과학회지
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    • 제6권6호
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    • pp.605-612
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    • 1997
  • This study is to evaluate the overall NPP(Net Primary Productions distribution in the Korean Peninsula from the satellite data(NOAA/AVHRR). This has been done using the linear relationship between the natural vegetation condition and the NPP. The NPP of natural vegetation increases proportional to the annual net radiation(Rn), where radiative dorless Index(RDI) is a proportional constant connecting Rn to NPP. Normalized Difference Vegetation Index(NDVI) Is used for monitoring vegetation change, and INDVI (Integrated NDVI) for annual analysis. The INDVI has a close relation to .Rn and NPP. which can be used effectively for estimating NPP distribution of where the meteorological data Is unavailable such as North Korea. The NPP distribution of the Korean Peninsula was estimated based on the model.

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Spatial Patterns of Anthropogenic Carbon Emission and Terrestrial Net Productivity

  • Ohta, Shunji;Kimura, Ai
    • 한국환경과학회지
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    • 제15권12호
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    • pp.1087-1091
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    • 2006
  • This paper describes the current spatial patterns of the net primary productivity (NPP) of the terrestrial vegetation and carbon emission (C) in the world due to the burning of fossil fuels in order to clarify the amount of expansion of human activity. The C/NPP value varies spatially from almost zero to several tens of thousand times the local NPP. C/NPP is higher under the condition of extensive human activities due to a high human population density or when the local NPP is extremely low in severe climatic zones. In contrast, the low C/NPP areas are distributed mainly in sparsely populated districts, loading to a low impact of human activity. Although the area where C/NPP is less than 10% accounts for about 70% of the entire land area, one-third of these areas cannot contribute to carbon absorption because of low NPP with a shortage of climatic resources. Since more than half of the areas of the remaining areas are agricultural land and forest ecosystems with high NPP, the possible afforestation area was evaluated to be maximum of $30{\times}10^{6}\;km^{2}$; here only sequestrate carbons that correspond to 2% of the global total NPP are present. These analyses revealed that presently most of the areas where the NPP is high are those exclusively used by humans and that it is difficult for large-scale forest plantations to absorb a substantial amount of the carbon emitted annually by humans.

Effects of Dietary Non-phytate Phosphorus Levels on Egg Production, Shell Quality and Nutrient Retention in White Leghorn Layers

  • Panda, A.K.;Rao, S.V.Rama;Raju, M.V.L.N.;Bhanja, S.K.
    • Asian-Australasian Journal of Animal Sciences
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    • 제18권8호
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    • pp.1171-1175
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    • 2005
  • An experiment was conducted (28 to 44 weeks) to study the laying performance, shell quality, and nutrient retention of White Leghorn layers fed different levels of non-phytate phosphorus (NPP). Six levels of NPP (0.15, 0.18, 0.21, 0.24, 0.27 and 0.30%) at a constant calcium (Ca) level (3.5%) in maize-soya-deoiled rice bran based diets were formulated, and each experimental diet was offered ad libitum for 16 weeks to five replicates with five birds in each replicate. The body weight of WL layers fed diet containing 0.15% NPP was significantly (p<0.05) lower than those fed diet with 0.30% NPP, at 44 weeks of age. However, the hen day egg production, egg weight, daily feed intake and feed consumed per dozen eggs were not influenced by the variation in the NPP levels in the diet. The bone ash content was significantly (p<0.05) higher in the birds fed 0.30% NPP as compared with those fed diets up to 0.24% NPP. Bone ash content was intermediate in the birds fed diet containing 0.27% NPP. The tibia strength followed the same trend as that of bone ash. Dietary NPP content had no influence on serum Ca and protein concentration and activity of alkaline phosphatase. However, serum inorganic P concentration increased linearly with NPP content in the diet. The concentration of P was significantly (p<0.05) higher in the birds fed 0.27% NPP or higher as compared with those fed 0.15% NPP. Levels of dietary NPP had no influence on egg quality parameters like shell wt, shell thickness, shell strength and specific gravity. The retention of nutrients such as DM, N and Ca were comparable among the WL layers fed different levels of NPP. However, the retention of P decreased linearly with increase in the level of NPP in the diet. The retention of P in the birds fed diets up to 0.24% NPP in the diet was comparable, however further increasing the content of NPP (either 0.27% or 0.30%) reduced the retention of P. Based on the results of the present study, 0.15% NPP (180 mg/b/d) in the diets of WL layers is adequate for optimum production performance during 28 to 44 weeks of age, however, WL layers require 0.27% NPP (324 mg /b/d) in the diet for optimum production with better bone mineralization.

기복이 심한 한반도 중서부 산림경관에서 기후가 순일차생산(NPP)에 미치는 영향에 대한 모사연구 (A Simulation Study to Investigate Climatic Controls on Net Primary Production (NPP) of a Rugged Forested Landscape in the Mid-Western Korean Peninsula)

  • 음성원;강신규;이도원
    • 한국농림기상학회지
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    • 제7권1호
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    • pp.66-77
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    • 2005
  • 과정-중심적인 생지화학 모형인 BIOME-BGC을 이용해 기복이 심한 산림유역에서 미기후가 순일차생산성(NPP)의 시공간적 변화에 미치는 영향을 조사하였다. 임분규모에서의 물과 탄소순환과정에 대한 모형예측 을 검증하기 위하여 2000년부터 각각 낙엽활엽수림 (DBF)과 상록침엽수림(ENF)에서 현장 조사를 수행하였다. 모형예측은 지온, 토양수분, 토양호흡 등의 다양한 현장 측정치들과 높은 상관성을 보였다. 모형에서 예측한 NPP의 계절변화는 기온과 높은 상관성을 보였으나, 물 관련 인자들과는 통계적으로 유의한 상관성이 나타나지 않았다. 반면에 여러 인자 중에서, 강우빈도가 NPP의 연변화를 설명하는 가장 좋은 기후인자로 판명되었다 또한 DBF 임분보다 ENF 임분의 NNP가 강우빈도에 보다 민감한 것으로 나타났다. 공간적인 NPP 분포는 조사 유역에서 식생피복 및 지형의 기복에 따라 매우 이질적으로 나타났는데, NPP 이질성의 정도는 NPP의 절대량과 음의 상관관계를 보였다. 이러한 결과는 생육환경이 부적절할 때에 산림경관에서의 NPP 이질성이 커짐을 보여준다. 본 연구결과에 의하면 본 조사유역의 NPP는 연간 1,400mm 이상의 많은 강우에도 불구하고 식생이 이용할 수 있는 물의 양에 의해 제한 받는다는 것을 알 수 있었으며, 이러한 모형연구결과는 향후 현장조사를 통하여 검증할 필요가 있다.

식생지수를 이용한 낙동강유역의 순일차생산량 산정 (Estimation of Net Primary Production for Nakdong River Basin using Vegetation Index)

  • 신사철;권기량
    • 한국지반환경공학회 논문집
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    • 제15권10호
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    • pp.35-42
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    • 2014
  • 본 연구는 낙동강유역에 대하여 MODIS 자료로부터 정규화식생지수 NDVI를 계산하여 순일차생산량 NPP를 산정하는 것이다. NPP를 산정함에 있어 기존의 방법을 벗어나 객관적 자료에 의한 자연식생 조건과 NPP 사이에는 선형의 관계가 성립한다는 성질을 이용하고 있다. 자연식생의 NPP는 식물이 흡수하는 가시광선의 양에 비례하며, 또한 이것은 NDVI와 비례하는 것으로 알려져 있다. 따라서 NDVI를 이용한 NPP 산정방법은 대단히 유효하게 이용될 수 있는 하나의 방법이다. 본 연구에서 제안한 방법은 직접 자료획득이 불가능한 넓은 지역 및 기상자료가 충분하지 않은 지역에서 유용하게 사용될 수 있다. 본 연구에서는 MODIS 센서에 의해 얻어진 NDVI에 근거한 NPP 추정 방안을 제안하고 경험적인 방법에 의해 계산된 값과 비교함으로써 본 연구 성과에 대한 검증을 실시하였다.

APR+원전 최초 호기의 CVAP 수행에 대한 제언 (Proposal for CVAP of First Plant of APR+ NPP)

  • 김동학;고도영;김만원
    • 한국소음진동공학회:학술대회논문집
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    • 한국소음진동공학회 2014년도 추계학술대회 논문집
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    • pp.399-401
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    • 2014
  • The comprehensive vibration assessment program(CVAP) of APR+ nuclear power plant(NPP) is classified as non-prototype, category II with Palo Verde NPP as valid prototype. In this paper, CVAP for first plant of APR+ NPP is proposed. The Control Element Assembly(CEA) shroud of APR+ NPP is different from that of Palo Verde NPP. And the Core Support Barrel(CSB) outer diameter and the flow rate of normal operation of APR+ NPP are larger than those of Palo Verde NPP. Vibration and stress analysis program should be conducted to establish test acceptance criteria. Limited vibration measurement program should be implemented to establish the margin of safety, demonstrate the satisfaction of test acceptance criteria and confirm the similar vibratory response between the APR+ and Palo Verde NPP. Because of the change of normal operation condition, the nominal differences between APR+ and Palo Verde NPP in the structural and hydraulic analysis are studied to determine the measurement locations.

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The Effects of Phytase Supplementation on the Performance of Broiler Chickens Fed Diets With Different Levels of Non-Phytate Phosphorus

  • Lim, H.S.;Namkung, H.;Um, J.S.;Kang, K.R.;Kim, B.S.;Paik, I.K.
    • Asian-Australasian Journal of Animal Sciences
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    • 제14권2호
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    • pp.250-257
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    • 2001
  • An experiment was conducted to determine the effects of phytase supplementation to the diets containing different levels of non-phytate phosphorus (NPP). A $3{\times}2$ factorial arrangement of treatments was employed. There were three dietary NPP levels of control (C) (0.45% for starter diet and 0.35% for grower diet), C-0.1% NPP (0.35% for starter diet and 0.25% for grower diet), and C-0.2% NPP (0.25% for starter diet and 0.15% for grower diet) and two phytase levels (0 and 500 U/kg). Reduced dietary NPP decreased feed intake and weight gain and increased mortality whereas dietary phytase increased feed intake and weight gain and decreased mortality. Supplemental phytase improved availabilities of dry matter, crude fat, ash, P, Zn, Mg, and Cu whereas dietary NPP level did not affect availabilities of nutrients except decreased Zn availability and increased Cu availability in reduced NPP diets. Nutrient retention of N, ash, Ca, P, Mg, and Zn were linearly decreased as dietary NPP levels reduced but dietary phytase increased their retention. Reduced dietary NPP increased ash excretion but decreased P and Cu excretion while dietary phytase decreased N excretion. Weight, length, girth and contents of ash, Ca, P and Mg of tibia linearly decreased as dietary NPP levels reduced. Dietary phytase increased length and ash content of tibia. It is concluded that dietary phytase can reduce P excretion and alleviate adverse affects caused by feeding low dietary NPP. Effects of phytase were greater in the lower NPP diets.

Effects of Phytase Supplementation on the Performance of Broiler Chickens Fed Maize and Wheat Based Diets with Different Levels of Non-phytate Phosphorus

  • Singh, P.K.;Khatta, V.K.;Thakur, R.S.;Dey, S.;Sangwan, M.L.
    • Asian-Australasian Journal of Animal Sciences
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    • 제16권11호
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    • pp.1642-1649
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    • 2003
  • An experiment was conducted to evaluate the effects of phytase supplementation on the growth performance, nutrients utilization and bone mineralization in broiler chickens. Day-old broiler chicks (n=480) were equally devided into eight treatment groups and fed maize or wheat based isocaloric, isonitrogenous and isocalcium diets having two non phytate phosphorus (NPP) concentrations (0.50% and 0.30%) and two phytase levels (0 and 500 phytase units/kg diet) in a 42 days growth trial. Maize based dietary treatments were MC (NPP 0.50%, MN (NPP 0.30%), MNP (MN+500 units of phytase) and MCP (MC+500 units of phytase), whereas wheat based experimental diets were WC (NPP 0.50%), WN (NPP 0.30%), WNP (WN+500 units of phytase) and WCP (WC+500 units of phytase). The NPP levels were maintained by dicalcium phosphate. Reduction in dietary NPP depressed live weight gain and feed intake and increased feed conversion ratio (FCR). Phytase supplementation to low NPP (0.30%) diets significantly (p<0.05) improved the growth performances of broilers. The supplementation to low NPP diets allowed complete, safe and economic replacement of dietary inorganic P (dicalcium phosphate) to reduce feed cost per kg live weight gain of broilers. Reduction in dietary NPP did not affect retention of nutrients except phosphorus (P) but had a significant (p<0.05) depression in tibia ash and minerals (Ca, P) concentration in serum and tibia ash. Phytase supplementation at low NPP level was effective (p<0.05) in improving the retention of dry matter, Ca and P and Ca and P concentration in serum and tibia ash. However, the supplementation was not effective at high level of NPP (0.50%). There were no significant (p>0.05) differences in carcass quality among dietary treatments. The response of phytase was greater in low NPP and maize based diets as compared with high NPP and wheat based diets, respectively. The results show that phytase supplementation to low NPP (0.30%) diets improved the growth performance, relative retention of nutrients (N, Ca and P) and minerals (Ca, P) status of blood and bone in broiler chickens, with a better efficacy in maize based diets.

비선형 광 곁가지를 갖는 고분자계의 증대된 비선형 특성 (Enhanced nonlinearity of nonlinear optical side-chain polymers)

  • 이종하;이황운;원영희;이석현
    • 한국광학회지
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    • 제11권1호
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    • pp.25-32
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    • 2000
  • 순수 N-(4-nitrophenyl)-(L)-prolinol (NPP)와 NPP를 곁가지로 갖는 poly(methyl metharcrylate) (PMMA) 및 poly(p-phenlene terephthalates) (PPT) 고분자계의 제 1차 초편극도 $\beta$를 전기장 인가 제 2고조파 발생(EFISHG)방법과 hyper-Rayleigh 산란(HRS) 방법으로 측정하여 비교하였다. 1,1,2,2,-tetrachloroethane 용액속의 순수 NPP와 NPP-PMMA 경우, 두 방법으로 구한 $\beta$측정값은 실험오차 이내에서 유사하였다. 그러나 1,1,2,2,-tetrachloroethane 용액속의 HNPP-PPT 고분자 경우 $\beta$측정 결과는 순수 NPP에 비하여 EFISHG에서는 9.7배 증대되고 HRS에서는 2.4배 증대되었다. 이 결과는 견고한 고분자 주사슬에 비선형 광 발색단을 곁가지로 갖는 고분자계에서는 직류 전기장속에서 발색단들이 고분자 2차 비선형 특성에 상호 보강적으로 기여하여 극성 고분자 사슬에서와 같이 증대된 것으로 해석하였다.

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