• Title/Summary/Keyword: central series

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Comparing LAI Estimates of Corn and Soybean from Vegetation Indices of Multi-resolution Satellite Images

  • Kim, Sun-Hwa;Hong, Suk Young;Sudduth, Kenneth A.;Kim, Yihyun;Lee, Kyungdo
    • Korean Journal of Remote Sensing
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    • v.28 no.6
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    • pp.597-609
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    • 2012
  • Leaf area index (LAI) is important in explaining the ability of the crop to intercept solar energy for biomass production and in understanding the impact of crop management practices. This paper describes a procedure for estimating LAI as a function of image-derived vegetation indices from temporal series of IKONOS, Landsat TM, and MODIS satellite images using empirical models and demonstrates its use with data collected at Missouri field sites. LAI data were obtained several times during the 2002 growing season at monitoring sites established in two central Missouri experimental fields, one planted to soybean (Glycine max L.) and the other planted to corn (Zea mays L.). Satellite images at varying spatial and spectral resolutions were acquired and the data were extracted to calculate normalized difference vegetation index (NDVI) after geometric and atmospheric correction. Linear, exponential, and expolinear models were developed to relate temporal NDVI to measured LAI data. Models using IKONOS NDVI estimated LAI of both soybean and corn better than those using Landsat TM or MODIS NDVI. Expolinear models provided more accurate results than linear or exponential models.

Effects of Synthetic Pseudoceramides on Sphingosine Kinase Activity in F9-12 Cells

  • Jin, You-Xun;Shin, Kyong-Oh;Park, Myung-Yong;Lee, Shin-Hee;Park, Byeong-Deog;Oh, Sei-Kwan;Yoo, Hwan-Soo;Lee, Yong-Moon
    • Biomolecules & Therapeutics
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    • v.19 no.1
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    • pp.134-139
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    • 2011
  • Sphingosine kinase (SPHK) has a central role to control cell death and cell proliferation, which is suggested as a sphingolipid rheostat by regulating the levels between ceramide and sphingosine 1-phosphate (S1P). Therefore, physiological regulators of SPHK will be a good candidate to develop a new targeted drug. For this purpose, a series of synthetic pseudoceramides were tested by SPHK assay either cell-based or cell-free system. K10PC-5 strongly inhibited SPHK, while K6PC-5 activated SPHK in cell-free system. Specifically, K6PC-5 activated SPHK under the co-treatment with $50\;{\mu}M$ dimethylsphingosine (DMS), a SPHK inhibitor. Collectively, we developed a simple SPHK assay system to find SPHK regulatory pseudoceramide compounds, K10PC-5 and K6PC-5 which may be useful to cancer treatment or immune regulation like FTY720, a synthetic sphingolipid mimetic compound.

Reconstruction of April-August Precipitation in Mt. Sorak Region from Tree Rings (나무나이테를 이용한 설악산 지역의 4월~8월 총강수량 복원)

  • ;;Liu Yu
    • The Korean Journal of Quaternary Research
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    • v.15 no.1
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    • pp.47-52
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    • 2001
  • April∼August precipitation (141 years : A.D. 1858∼1998) of Mt. Sorak region (East-central Korea) was reconstructed using a tree-ring chronology of Pinus densiflora sampled from Beakdam Shelter area. During the reconstructed Periods, dry periods were 1880∼1887, 1893∼1901 and 1922∼1938, and wet one 1906∼1918. In the long-term variation, the late 19th and early 20th century were drier than the late 20th century. Major wet/dry periodicities in April∼August precipitation series reconstructed were 3.16 and 4.14 years, indicating that short-term variation were more prominent than long-term one.

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Fundamental Studies on the Net-Shape of the Drag Net ( III ) - The Relationship between the Section Shape and the Porosity of Netting in the Bag Net - (저예망의 어구형상에 관한 기초적 연구 III)

  • 이주희
    • Journal of the Korean Society of Fisheries and Ocean Technology
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    • v.21 no.2
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    • pp.89-98
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    • 1985
  • As a primary step in studying the effects of the netting porosity on the net-shape in the four-seam trawling net, a series of experiments were performed changing the porosity of each panel, with the simplified mo:iel of the bag net made of porous vinyl film and that ma:ie of net webbing. These models were suspended horizontally in circularly flowing water, with two pairs of susp~nding threais to four points of symetry at the border of the bag mouth in place of both wing nets. And then, the section shape of the bag mouth photographed and the tensions on both pairs of suspending threads were measured with two load cells in circularly flowing water. From the results, the auther estimated an experimental equation from the relationship between the porosity of each panel in the bag net and the section shape of the bag mouth, h/w=k (l-Pr_u/lPr_s)

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Interactive Information Retrieval: An Introduction

  • Borlund, Pia
    • Journal of Information Science Theory and Practice
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    • v.1 no.3
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    • pp.12-32
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    • 2013
  • The paper introduces the research area of interactive information retrieval (IIR) from a historical point of view. Further, the focus here is on evaluation, because much research in IR deals with IR evaluation methodology due to the core research interest in IR performance, system interaction and satisfaction with retrieved information. In order to position IIR evaluation, the Cranfield model and the series of tests that led to the Cranfield model are outlined. Three iconic user-oriented studies and projects that all have contributed to how IIR is perceived and understood today are presented: The MEDLARS test, the Book House fiction retrieval system, and the OKAPI project. On this basis the call for alternative IIR evaluation approaches motivated by the three revolutions (the cognitive, the relevance, and the interactive revolutions) put forward by Robertson & Hancock-Beaulieu (1992) is presented. As a response to this call the 'IIR evaluation model' by Borlund (e.g., 2003a) is introduced. The objective of the IIR evaluation model is to facilitate IIR evaluation as close as possible to actual information searching and IR processes, though still in a relatively controlled evaluation environment, in which the test instrument of a simulated work task situation plays a central part.

Isolation of Sangivamycin from Streptomyces sp. A6497 and its Herbicidal Activity

  • HWANG EUI IL;YUN BONG SIK;CHOI SUNG WON;KIM JIN SEOG;LIM SE JIN;MOON JAE SUN;LEE SANG HAN;KIM SUNG UK
    • Journal of Microbiology and Biotechnology
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    • v.15 no.2
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    • pp.434-437
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    • 2005
  • During the screening for the inhibitors of cellulose biosynthesis as herbicides, we discovered a Streptomyces sp. A6497 with a selective antifungal activity against cellulose containing Phytophthora parasitica, but not against cellulose lacking Candida albicans. The inhibitor was isolated and identified, using a series of chromatographies. Based on structure analyses with UV spectrophotometry, mass and various NMR, the inhibitor was identified as sangivamycin. The compound exhibited strong antifungal activities against P. parasitica (MIC; 3.125 $\mu$g/ml). In particular, it showed strong herbicidal activities against various weeds in the greenhouse experiment. Taken together, these results suggest that sangivamycin is a useful lead compound for the development of new herbicides.

MR damping system for mitigating wind-rain induced vibration on Dongting Lake Cable-Stayed Bridge

  • Chen, Z.Q.;Wang, X.Y.;Ko, J.M.;Ni, Y.Q.;Spencer, B.F.;Yang, G.;Hu, J.H.
    • Wind and Structures
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    • v.7 no.5
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    • pp.293-304
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    • 2004
  • The Dongting Lake Bridge is a cable-stayed bridge crossing the Dongting Lake where it meets the Yangtze River in southern central China. Several intensive wind-rain induced vibrations had been observed since its open to traffic in 1999. To investigate the possibility of using MR damping systems to reduce cable vibration, a series of field tests were conducted. Based on the promising research results, MR damping system was installed on the longest 156 stay cables of Dongting Lake Bridge in June 2002, making it the worlds first application of MR dampers on cable-stayed bridge to suppress the wind-rain induced cable vibration. As a visible and permanent aspect of the bridge, the MR damping system must be aesthetically pleasing, reliable, durable, easy to maintain, as well as effective in vibration mitigation. Substantial work was done to meet these requirements. This paper describes field tests and the implementation of MR damping systems for cable vibration reduction. Three-years reliable service of this system proves its durability.

A NoSQL data management infrastructure for bridge monitoring

  • Jeong, Seongwoon;Zhang, Yilan;O'Connor, Sean;Lynch, Jerome P.;Sohn, Hoon;Law, Kincho H.
    • Smart Structures and Systems
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    • v.17 no.4
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    • pp.669-690
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    • 2016
  • Advances in sensor technologies have led to the instrumentation of sensor networks for bridge monitoring and management. For a dense sensor network, enormous amount of sensor data are collected. The data need to be managed, processed, and interpreted. Data management issues are of prime importance for a bridge management system. This paper describes a data management infrastructure for bridge monitoring applications. Specifically, NoSQL database systems such as MongoDB and Apache Cassandra are employed to handle time-series data as well the unstructured bridge information model data. Standard XML-based modeling languages such as OpenBrIM and SensorML are adopted to manage semantically meaningful data and to support interoperability. Data interoperability and integration among different components of a bridge monitoring system that includes on-site computers, a central server, local computing platforms, and mobile devices are illustrated. The data management framework is demonstrated using the data collected from the wireless sensor network installed on the Telegraph Road Bridge, Monroe, MI.

Bacillus sp. BS061 Suppresses Gray Mold and Powdery Mildew through the Secretion of Different Bioactive Substances

  • Kim, Young-Sook;Song, Ja-Gyeong;Lee, In-Kyoung;Yeo, Woon-Hyung;Yun, Bong-Sik
    • Mycobiology
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    • v.41 no.3
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    • pp.164-166
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    • 2013
  • A Bacillus sp. BS061 significantly reduced disease incidence of gray mold and powdery mildew. To identify the active principle, the culture filtrate was partitioned between butanol and water. The antifungal activity against B. cinerea was evident in the butanol-soluble portion, and active substances were identified as cyclic lipopeptides, iturin A series, by nuclear magnetic resonance spectrometry (NMR) and mass analysis. Interestingly, antifungal activity against powdery mildew was observed in the water-soluble portion, suggesting that cyclic lipopeptides have no responsibility to suppress powdery mildew. This finding reveals that biocontrol agents of Bacillus origin suppress gray mold and powdery mildew through the secretion of different bioactive substances.

A Study on the Approximate Analysis of the Bending Moment for the Three-Span Continuous Curved Girder Bridges with Constant Cross Section (등단면 3경간 연속 곡선격자형교의 휨모멘트 근사해석에 관한 연구)

  • Chang, Byung Soon;Seo, Sang Geun;Cha, Ki Hyuk
    • Journal of Korean Society of Steel Construction
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    • v.11 no.2 s.39
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    • pp.131-142
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    • 1999
  • The general behavior of the curved girder including the warping effects can be presented as the series of differential equations developed by Vlasov. Generally, bending moment is the most important factor for engineer to decide the section of the girder. In order to accommodate easiness of the structural analysis for the curved girder bridge, this paper suggest the ratios of bending moment of curved gilder to that of straight girder. These ratios are presented by an approximate formula setting central angle ${\theta}(L/R)$ as a variable. The approximate formula of the maximum bending moment ratios and influence lines of all stress resultants can be used to design the three-span curved girder bridges.

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