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Sea Ice Observations in Polar Regions: Evolution of technologies in Remote Sensing

International journal of Geosciences 2013年第7期4卷 1031-1050页

作者： Praveen Rao teleti Alvarinho j. Luis Earth System Sciences Organization National Centre for Antarctic and Ocean Research Ministry of Earth Sciences Goa India

Evolution of remote sensing sensors technologies is presented, with emphasis on its suitability in observing the polar regions. the extent of influence of polar regions on the global climate and vice versa is the spearhead of climate change research. the extensive cover of sea ice has major impacts on the atmosphere, oceans, and terrestrial and marine ecosystems of the polar regions in particular and teleconnection on other processes elsewhere. Sea ice covers vast areas of the polar oceans, ranging from ~18 × 106 km2 to ~23 × 106 km2, combined for the Northern and Southern Hemispheres. However, both polar regions are witnessing contrasting rather contradicting effects of climate change. the Arctic sea ice extent is declining at a rate of 0.53 × 106 km2·decade–1, whereasAntarcticaexhibits a positive trend at the rate of 0.167 × 106 km2·decade–1. this work reviews literature published in the field of sea ice remote sensing, to evaluate and access success and failures of different sensors to observe physical features of sea ice. the chronological development series of different sensors on different satellite systems, sensor specifications and datasets are examined and how they have evolved to meet the growing needs of users is outlined. Different remote sensing technology and observational methods and their suitability to observe specific sea ice property are also discussed. A pattern has emerged, which shows that microwave sensors are inherently superior to visible and infrared in monitoring seasonal and annual changes in sea ice. Degree of successes achieved through remote sensing techniques by various investigators has been compared. Some technologies appear to work better under certain conditions than others, and it is now well accepted that there is no algorithm that is ideal globally. Contribution of Indian remote sensing satellites is also reviewed in the context of polar research. this review suggests different primary datasets for further research on sea ice f

关键词： Sea Ice Satellite Remote Sensing Polar Regions Albedo

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A NOVEL LOW tEMPERAtURE BLACK LIQUOR GASIFICAtION SYStEM FOR RECOVERY OF PULPING CHEMICALS

A NOVEL LOW TEMPERATURE BLACK LIQUOR GASIFICATION SYSTEM FOR...

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2004中国造纸学会学术报告会

作者： Eric j．Connor Senior vice President thermochem Recovery Intl. Baltimore Maryland USA

＜正＞A Novel Low temperature Black Liquor Gasification System for Recovery of Pulping Chemicals Eric Connor Slide One;Introduction this presentation will provide an update on the start-up and operation of the world’...

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Co-operation between *** tungsheng and Myself

Co-operation between *** Tungsheng and Myself

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作者： jrg F.W.Negendank GeoForschungs Zentrum

In 1991,as vice President and geologist of the University of trier,Germany I had the obligation to visit partner universities in japan and China to strengthen the contacts for our students being educated in both countries in both languages and *** from these commitments I participated in the INQUA congress at Beijing congress center and met *** tungsheng personally for the first time.

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Professor jian Ge:the road to the success of scientific research

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Eye Science 2016年第1期31卷 50-54页

作者： Helen X.Seliman Molly j.Wang ES

Professor jian Ge(Figure 1)currently is member of standing committee of the Asia Pacific Glaucoma Society,Honorary Chairman of the Chinese Ophthalmologic Society,vice chairman of the Chinese Eye Doctor Association,For... 详细信息

关键词：科学研究学会青光眼眼科中华副主席

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绿色植物靶标的光谱探测研究

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光谱学与光谱分析 2010年第8期30卷 2179-2183页

作者：邓巍赵春江何雄奎陈立平张录达武广伟 Mueller j 翟长远国家农业信息化工程技术研究中心北京100097 中国农业大学理学院北京100193 University of Hohenheim 700599 StuttgartGermany

利用植物和背景(枯枝、土壤等)的光谱特性"红边"两侧反射率的差异,研究了探测绿色植物靶标的光谱探测技术。定义850与650nm处反射率的比值为植物判别指数(GPDI)。用FieldSpec Handheld2500型野外便携式光谱仪测量了绿色植物和背景的光... 详细信息

利用植物和背景(枯枝、土壤等)的光谱特性"红边"两侧反射率的差异,研究了探测绿色植物靶标的光谱探测技术。定义850与650nm处反射率的比值为植物判别指数(GPDI)。用FieldSpec Handheld2500型野外便携式光谱仪测量了绿色植物和背景的光谱数据,对其进行数据处理,计算各被测物质的植物判别指数GPDI。利用决策树模式识别方法建立植物与背景的分类模型,得到了GPDI阈值(GPDItH),选择此阈值为5.54。当GPDI>GPDItH时,判别探测对象为植物;反之亦然。设计开发了基于At89S51单片机和光电二极管OPt101的绿色植物光谱探测器。试验结果表明,此探测器的探测率受杂草的种类、大小和密度的影响;阔叶草比窄叶草更易探测到;植株越大、密度越高,探测率越高。

关键词：光谱探测绿色植物判别指数(GPDI) 光谱“红边”

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基于长期研究队列的广西隆安县乙型肝炎病毒准种研究

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中国热带医学 2023年第8期23卷 822-827页

作者：贾蕙华陈钦艳蒋智华王学燕张文嘉 tIM j Harrison j BROOKS jackson LI Wu 方钟燎广西壮族自治区疾病预防控制中心广西病毒性肝炎防制研究重点实验室广西南宁530021 广西医科大学基础医学院广西南宁530021 Division of Medicine University College London Medical SchoolLondonUK Carver College of Medicine University of IowaIowa CityUSA

目的明确广西隆安县队列HBsAg无症状携带者感染的乙型肝炎病毒(hepatitis B virus,HBV)准种序列长期演化特征。方法收集9名广西隆安县队列HBsAg无症状携带者2004年、2007年、2013年、2019年或2020年4个不同时间点血清样本。酶联免疫吸... 详细信息

目的明确广西隆安县队列HBsAg无症状携带者感染的乙型肝炎病毒(hepatitis B virus,HBV)准种序列长期演化特征。方法收集9名广西隆安县队列HBsAg无症状携带者2004年、2007年、2013年、2019年或2020年4个不同时间点血清样本。酶联免疫吸附测定法检测HBV血清学标志物;聚合酶链式反应(polymerase chain reaction,PCR)荧光探针法检测HBV病毒载量;试剂盒提取HBV DNA;PCR法扩增HBV全基因组,进行二代测序;利用Mega等软件对所获得的序列进行生物信息学分析。结果共获得23份血清样本,309条全长基因准种序列,每份标本平均获得(0.18±0.07)G测序数据量。55.55%(5/9)的研究对象携带的HBV毒株基因型在长期进化过程中发生了基因型转换,PreS/S区系统进化树基因分型结果与全基因组分析结果完全一致;发现B/C、I/C重组体;各研究标本的Sn值范围为0~0.37,D值范围为0~0.11;共检出21种特殊单核苷酸/氨基酸突变位点(S区7种,X区2种,PreC区3种,BCP区9种)和6种缺失突变,发现多联突变组合形式,未发现任何耐药突变,77.8%(7/9)研究对象在2004年携带的HBV毒株发生了BCP区nt1762(A→t)/1764(G→A)双突变和PreC区1896位(G→A)点突变,HBV基因可在无抗病毒药物压力下由突变型可恢复为野生型和(或)野生型转变为突变型;HBV基因组进化率为2.03×10^(-5)~3.50×10^(-3)。结论在HBV自然感染进程中,HBV基因型和重组体、准种复杂性和多样性可随时间发生改变;HBV基因突变型和野生型可相互转换,一定程度上降低了利用基因型和相关突变来预测临床结局的价值;隆安县乙型肝炎表面抗原(hepatitis B surface antigen,HBsAg)无症状携带者HBV基因组进化率很高。

关键词：乙型肝炎病毒基因型二代测序准种基因突变

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Phenotypic diversity of rapeseed accessions from different geographic locations

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Oil Crop Science 2016年第1期1卷 9-20页

作者： Hongyun tIAN Wei LI Vratislav KUCERAC Michael j.StAMM Shengwu HU State Key Laboratory of Crop Stress Biology in Arid Areas and College of Agronomy Northwest A&F UniversityYangling 112100 P. R. China Crop Designing Centre Henan Academy of Agricultural Sciences Zhengzhou 450002 P. R. China Crop Research Institute Drnovska 507 Prague 6 16106 Czech Republic Department of Agronomy Kansas State University Manhattan KS 66506 USA

It is essential to evaluate agronomic and quality traits when using elite lines in rapeseed （Brassica napus L. ） breeding. 92 rapeseed accessions （44 Chinese, 22 European, 16 USA and 10 Ca-nadian） were evaluated by 16 agronomic and quality traits in Northern China. Analysis of variance among the 92 accessions revealed significant differences on 13 traits. the 13 traits were plant height, setting po-sition of the first primary branch, silique number （ on terminal raceme） , silique density, siliques per plant, seeds per silique, thousand seed weight, seed yield per plant, flowering time, final flowering, ma-turity time, cold mortality, and oil content. Other 3 traits were not significant （primary branches per plant, terminal raceme length and seed protein） . Cluster analysis revealed that 92 accessions were clus-tered into 3 major groups. the 1st group had 10 Canadian and 5 Chinese. the 2nd group had 33 acces-sions from China and 5 from Europe. the 3rd group had 39 accessions from Europe and the USA. For ag-ronomy and quality traits, 45. 73% genetic variation attributed to differences among populations of geo-graphic regions, and 54. 27% attributed to differences within geographic regions. In summary, the a-broad accessions were distinguished from domestic ones, and could be used as important germplasm re-sources for enriching the genetic background of Chinese rapeseed, and vice versa.

关键词： Brassica napus L. agronomic traits quality traits genetic diversity

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Difference in Unbalanced Magnetic Force of Fractional-Slot PM Machines between Internal and External Rotor topologie

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CES transactions on Electrical Machines and Systems 2017年第2期1卷 154-163页

作者： L.j.Wu Z.Q.Zhu Youtong Fang Xiaoyan Huang College of Electrical Engineering Zhejiang UniversityChina epartment of electronic and electrical engineering university of sheffieldmappin streetsheffields13jduk Royal Academy of Engineering

this paper presents a comparative investigation into unbalanced magnetic force(UMF)of asymmetric permanent magnet machines without rotor eccentricities,particularly focusing on the difference between internal-and external-rotor *** asymmetric field distribution results in radial and tangential asymmetric force *** the radial and tangential stresses are in different direction,the UMF components they produce are nearly *** UMF from asymmetric radial force wave can be additive or subtractive to that from asymmetric tangential force *** shows that for the same pole slot number combination,if the UMFs due to radial and tangential force waves are additive in internal rotor machine,they are subtractive in the external rotor counterpart,and vice *** reveals a general rule determining whether additive or cancelling:for a UMF produced by any two field harmonics,they are additive if the higher order is produced by the outer part outside the airgap,but cancelling if the higher order is produced by the inner ***,for a machine with pole number 2p=3k+1,they are additive if it is an external-rotor machine,but otherwise *** the other hand,for a machine with pole number 2p=3k-1,they are subtractive if it is an external-rotor machine,but otherwise *** the UMF due to armature reaction only,they are subtractive for external-rotor machines,but otherwise *** investigation is carried out by an analytical model and validated by finite element analysis.

关键词： Analytical model electric machines fractional-slot machines permanent magnet machines unbalanced magnetic force

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Scale Effects of StAtSGO and SSURGO on Flow and Water Quality Predictions

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journal of Water Resource and Protection 2013年第3期5卷 266-274页

作者： Prasanna H. Gowda David j. Mulla Vinay Nangia Srinivasulu Ale Department of Soil Water and Climate University of Minnesota St. Paul USA International Center for Agricultural Research in Dry Areas Amman Jordan texas A&M AgriLife Research Vernon USA USDA-ARS Conservation and Production Research Laboratory Bushland USA

Soil information is one of the crucial inputs needed to assess the impacts of existing and alternative agricultural management practices on water quality. therefore, it is important to understand the effects of spatial scale at which soil databases are developed on water quality evaluations. In the United States, StAtSGO (State Soils Geographic) and SSURGO (Soil Survey Geographic) are the most commonly available soil databases. the purpose of this paper was to quantify the effect of scale by employing StAtSGO (1:250,000) and SSURGO (1:24,000) soil databases in predicting and comparing flow, sediment, nitrate and phosphorus losses for High Island Creek. this watershed is predominately agricultural and located in south-central Minnesota. the ADAPt (Agricultural Drainage and Pesticide transport), model was calibrated for flow, sediment, nitrate and phosphorus losses over two years (2001-2002) using StAtSGO and SSURGO soil databases. then the calibrated model was used to evaluate alternative tillage and fertilizer management practices such as adoption of conservation tillage, and rate, timing and method of N- and P-fertilizer applications. Statistical comparison of calibration results with observed data indicated excellent agreement for both soil databases (StAtSGO with r2 of 0.95, 0.97, 0.77 and 0.92 and SSURGO with r2 of 0.90, 0.97, 0.82 and 0.99 for flow, sediment, nitrate and phosphorus losses, respectively). However, StAtSGO based predictions of annual nitrate-N losses were consistently greater than those with SSURGO database and vice-versa for predicted annual phosphorus losses for the alternative management practice that were evaluated.

关键词： total Maximum Daily Loads Watershed Management Agricultural Best Management Practices ADAPt

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Are there tea Parties on mars？ Business and Politics in Science Fiction Films

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journal of Literature and Art Studies 2012年第3期2卷 382-396页

作者： O＇Brien Stanley Nicki L. Michalski Ruth j. H. Stanley Lamar University Beaumont USA

this paper will apply a politically oriented description-critique paradigm developed from the works of Whitehall and Grewell that offers a way to examine works of popular culture, particularly mars-based science fiction films. Because of the unique nature of these films, primarily which they are set in a future and distant world, they allow us to explore the socio-political landscape in which they were created from a remove that does not exist in ＂real-world＂ based works. Specifically we will be examining the governing power （in any particular mars-based science fiction film） that might be either wielded by business interests or governmental interests. Although it is possible to have both a strong government and a strong business in a society, in many mars-based science fiction films, government and business seem to represent two sides of a continuum. the stronger the business power structure in the film, the weaker the governmental power structure, and vice-versa.

关键词： science fiction mars political structure governmental power Geoffrey Whitehall Gary Grewell colonization film

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